summaryrefslogtreecommitdiff
path: root/third_party/uip-1.0/doc/html/a00201.html
blob: 010d21611f1d3431361abe64f93c33203bd5d1ab (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1">
<title>uIP 1.0: uip/uip.c Source File</title>
<link href="doxygen.css" rel="stylesheet" type="text/css">
<link href="tabs.css" rel="stylesheet" type="text/css">
</head><body>
<!-- Generated by Doxygen 1.4.6 -->
<div class="tabs">
  <ul>
    <li><a href="main.html"><span>Main&nbsp;Page</span></a></li>
    <li><a href="modules.html"><span>Modules</span></a></li>
    <li><a href="classes.html"><span>Data&nbsp;Structures</span></a></li>
    <li id="current"><a href="files.html"><span>Files</span></a></li>
    <li><a href="examples.html"><span>Examples</span></a></li>
  </ul></div>
<div class="tabs">
  <ul>
    <li><a href="files.html"><span>File&nbsp;List</span></a></li>
    <li><a href="globals.html"><span>Globals</span></a></li>
  </ul></div>
<h1>uip/uip.c</h1><a href="a00135.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a><a class="code" href="a00135.html#534d9e416324fb8ecca6b9cb4b1f6a6a">00001</a> <span class="preprocessor">#define DEBUG_PRINTF(...) </span><span class="comment">/*printf(__VA_ARGS__)*/</span>
<a name="l00002"></a>00002 <span class="comment"></span>
<a name="l00003"></a>00003 <span class="comment">/**</span>
<a name="l00004"></a>00004 <span class="comment"> * \defgroup uip The uIP TCP/IP stack</span>
<a name="l00005"></a>00005 <span class="comment"> * @{</span>
<a name="l00006"></a>00006 <span class="comment"> *</span>
<a name="l00007"></a>00007 <span class="comment"> * uIP is an implementation of the TCP/IP protocol stack intended for</span>
<a name="l00008"></a>00008 <span class="comment"> * small 8-bit and 16-bit microcontrollers.</span>
<a name="l00009"></a>00009 <span class="comment"> *</span>
<a name="l00010"></a>00010 <span class="comment"> * uIP provides the necessary protocols for Internet communication,</span>
<a name="l00011"></a>00011 <span class="comment"> * with a very small code footprint and RAM requirements - the uIP</span>
<a name="l00012"></a>00012 <span class="comment"> * code size is on the order of a few kilobytes and RAM usage is on</span>
<a name="l00013"></a>00013 <span class="comment"> * the order of a few hundred bytes.</span>
<a name="l00014"></a>00014 <span class="comment"> */</span>
<a name="l00015"></a>00015 <span class="comment"></span>
<a name="l00016"></a>00016 <span class="comment">/**</span>
<a name="l00017"></a>00017 <span class="comment"> * \file</span>
<a name="l00018"></a>00018 <span class="comment"> * The uIP TCP/IP stack code.</span>
<a name="l00019"></a>00019 <span class="comment"> * \author Adam Dunkels &lt;adam@dunkels.com&gt;</span>
<a name="l00020"></a>00020 <span class="comment"> */</span>
<a name="l00021"></a>00021 
<a name="l00022"></a>00022 <span class="comment">/*</span>
<a name="l00023"></a>00023 <span class="comment"> * Copyright (c) 2001-2003, Adam Dunkels.</span>
<a name="l00024"></a>00024 <span class="comment"> * All rights reserved.</span>
<a name="l00025"></a>00025 <span class="comment"> *</span>
<a name="l00026"></a>00026 <span class="comment"> * Redistribution and use in source and binary forms, with or without</span>
<a name="l00027"></a>00027 <span class="comment"> * modification, are permitted provided that the following conditions</span>
<a name="l00028"></a>00028 <span class="comment"> * are met:</span>
<a name="l00029"></a>00029 <span class="comment"> * 1. Redistributions of source code must retain the above copyright</span>
<a name="l00030"></a>00030 <span class="comment"> *    notice, this list of conditions and the following disclaimer.</span>
<a name="l00031"></a>00031 <span class="comment"> * 2. Redistributions in binary form must reproduce the above copyright</span>
<a name="l00032"></a>00032 <span class="comment"> *    notice, this list of conditions and the following disclaimer in the</span>
<a name="l00033"></a>00033 <span class="comment"> *    documentation and/or other materials provided with the distribution.</span>
<a name="l00034"></a>00034 <span class="comment"> * 3. The name of the author may not be used to endorse or promote</span>
<a name="l00035"></a>00035 <span class="comment"> *    products derived from this software without specific prior</span>
<a name="l00036"></a>00036 <span class="comment"> *    written permission.</span>
<a name="l00037"></a>00037 <span class="comment"> *</span>
<a name="l00038"></a>00038 <span class="comment"> * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS</span>
<a name="l00039"></a>00039 <span class="comment"> * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED</span>
<a name="l00040"></a>00040 <span class="comment"> * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE</span>
<a name="l00041"></a>00041 <span class="comment"> * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY</span>
<a name="l00042"></a>00042 <span class="comment"> * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL</span>
<a name="l00043"></a>00043 <span class="comment"> * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE</span>
<a name="l00044"></a>00044 <span class="comment"> * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS</span>
<a name="l00045"></a>00045 <span class="comment"> * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,</span>
<a name="l00046"></a>00046 <span class="comment"> * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING</span>
<a name="l00047"></a>00047 <span class="comment"> * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS</span>
<a name="l00048"></a>00048 <span class="comment"> * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.</span>
<a name="l00049"></a>00049 <span class="comment"> *</span>
<a name="l00050"></a>00050 <span class="comment"> * This file is part of the uIP TCP/IP stack.</span>
<a name="l00051"></a>00051 <span class="comment"> *</span>
<a name="l00052"></a>00052 <span class="comment"> * $Id: uip.c,v 1.65 2006/06/11 21:46:39 adam Exp $</span>
<a name="l00053"></a>00053 <span class="comment"> *</span>
<a name="l00054"></a>00054 <span class="comment"> */</span>
<a name="l00055"></a>00055 
<a name="l00056"></a>00056 <span class="comment">/*</span>
<a name="l00057"></a>00057 <span class="comment"> * uIP is a small implementation of the IP, UDP and TCP protocols (as</span>
<a name="l00058"></a>00058 <span class="comment"> * well as some basic ICMP stuff). The implementation couples the IP,</span>
<a name="l00059"></a>00059 <span class="comment"> * UDP, TCP and the application layers very tightly. To keep the size</span>
<a name="l00060"></a>00060 <span class="comment"> * of the compiled code down, this code frequently uses the goto</span>
<a name="l00061"></a>00061 <span class="comment"> * statement. While it would be possible to break the uip_process()</span>
<a name="l00062"></a>00062 <span class="comment"> * function into many smaller functions, this would increase the code</span>
<a name="l00063"></a>00063 <span class="comment"> * size because of the overhead of parameter passing and the fact that</span>
<a name="l00064"></a>00064 <span class="comment"> * the optimier would not be as efficient.</span>
<a name="l00065"></a>00065 <span class="comment"> *</span>
<a name="l00066"></a>00066 <span class="comment"> * The principle is that we have a small buffer, called the uip_buf,</span>
<a name="l00067"></a>00067 <span class="comment"> * in which the device driver puts an incoming packet. The TCP/IP</span>
<a name="l00068"></a>00068 <span class="comment"> * stack parses the headers in the packet, and calls the</span>
<a name="l00069"></a>00069 <span class="comment"> * application. If the remote host has sent data to the application,</span>
<a name="l00070"></a>00070 <span class="comment"> * this data is present in the uip_buf and the application read the</span>
<a name="l00071"></a>00071 <span class="comment"> * data from there. It is up to the application to put this data into</span>
<a name="l00072"></a>00072 <span class="comment"> * a byte stream if needed. The application will not be fed with data</span>
<a name="l00073"></a>00073 <span class="comment"> * that is out of sequence.</span>
<a name="l00074"></a>00074 <span class="comment"> *</span>
<a name="l00075"></a>00075 <span class="comment"> * If the application whishes to send data to the peer, it should put</span>
<a name="l00076"></a>00076 <span class="comment"> * its data into the uip_buf. The uip_appdata pointer points to the</span>
<a name="l00077"></a>00077 <span class="comment"> * first available byte. The TCP/IP stack will calculate the</span>
<a name="l00078"></a>00078 <span class="comment"> * checksums, and fill in the necessary header fields and finally send</span>
<a name="l00079"></a>00079 <span class="comment"> * the packet back to the peer.</span>
<a name="l00080"></a>00080 <span class="comment">*/</span>
<a name="l00081"></a>00081 
<a name="l00082"></a>00082 <span class="preprocessor">#include "<a class="code" href="a00136.html">uip.h</a>"</span>
<a name="l00083"></a>00083 <span class="preprocessor">#include "<a class="code" href="a00140.html">uipopt.h</a>"</span>
<a name="l00084"></a>00084 <span class="preprocessor">#include "<a class="code" href="a00137.html">uip_arch.h</a>"</span>
<a name="l00085"></a>00085 
<a name="l00086"></a>00086 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l00087"></a>00087 <span class="preprocessor"></span><span class="preprocessor">#include "<a class="code" href="a00132.html">uip-neighbor.h</a>"</span>
<a name="l00088"></a>00088 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00089"></a>00089 
<a name="l00090"></a>00090 <span class="preprocessor">#include &lt;string.h&gt;</span>
<a name="l00091"></a>00091 
<a name="l00092"></a>00092 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00093"></a>00093 <span class="comment">/* Variable definitions. */</span>
<a name="l00094"></a>00094 
<a name="l00095"></a>00095 
<a name="l00096"></a>00096 <span class="comment">/* The IP address of this host. If it is defined to be fixed (by</span>
<a name="l00097"></a>00097 <span class="comment">   setting UIP_FIXEDADDR to 1 in uipopt.h), the address is set</span>
<a name="l00098"></a>00098 <span class="comment">   here. Otherwise, the address */</span>
<a name="l00099"></a>00099 <span class="preprocessor">#if UIP_FIXEDADDR &gt; 0</span>
<a name="l00100"></a>00100 <span class="preprocessor"></span><span class="keyword">const</span> <a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a> <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a> =
<a name="l00101"></a>00101   {<a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>((UIP_IPADDR0 &lt;&lt; 8) | UIP_IPADDR1),
<a name="l00102"></a>00102    <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>((UIP_IPADDR2 &lt;&lt; 8) | UIP_IPADDR3)};
<a name="l00103"></a>00103 <span class="keyword">const</span> <a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a> <a class="code" href="a00150.html#g20df5c82f2a15a508c19e505b5d9de2b">uip_draddr</a> =
<a name="l00104"></a>00104   {<a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>((UIP_DRIPADDR0 &lt;&lt; 8) | UIP_DRIPADDR1),
<a name="l00105"></a>00105    <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>((UIP_DRIPADDR2 &lt;&lt; 8) | UIP_DRIPADDR3)};
<a name="l00106"></a>00106 <span class="keyword">const</span> <a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a> <a class="code" href="a00150.html#g3237be0d9ec457de0177689ee23c0d5c">uip_netmask</a> =
<a name="l00107"></a>00107   {<a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>((UIP_NETMASK0 &lt;&lt; 8) | UIP_NETMASK1),
<a name="l00108"></a>00108    <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>((UIP_NETMASK2 &lt;&lt; 8) | UIP_NETMASK3)};
<a name="l00109"></a>00109 <span class="preprocessor">#else</span>
<a name="l00110"></a><a class="code" href="a00150.html#g3237be0d9ec457de0177689ee23c0d5c">00110</a> <span class="preprocessor"></span><a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a> <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>, <a class="code" href="a00150.html#g20df5c82f2a15a508c19e505b5d9de2b">uip_draddr</a>, uip_netmask;
<a name="l00111"></a>00111 <span class="preprocessor">#endif </span><span class="comment">/* UIP_FIXEDADDR */</span>
<a name="l00112"></a>00112 
<a name="l00113"></a>00113 <span class="keyword">static</span> <span class="keyword">const</span> <a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a> all_ones_addr =
<a name="l00114"></a>00114 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l00115"></a>00115 <span class="preprocessor"></span>  {0xffff,0xffff,0xffff,0xffff,0xffff,0xffff,0xffff,0xffff};
<a name="l00116"></a>00116 <span class="preprocessor">#else </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00117"></a>00117   {0xffff,0xffff};
<a name="l00118"></a>00118 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00119"></a>00119 <span class="keyword">static</span> <span class="keyword">const</span> <a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a> all_zeroes_addr =
<a name="l00120"></a>00120 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l00121"></a>00121 <span class="preprocessor"></span>  {0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000};
<a name="l00122"></a>00122 <span class="preprocessor">#else </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00123"></a>00123   {0x0000,0x0000};
<a name="l00124"></a>00124 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00125"></a>00125 
<a name="l00126"></a>00126 
<a name="l00127"></a>00127 <span class="preprocessor">#if UIP_FIXEDETHADDR</span>
<a name="l00128"></a>00128 <span class="preprocessor"></span><span class="keyword">const</span> <span class="keyword">struct </span><a class="code" href="a00089.html">uip_eth_addr</a> <a class="code" href="a00150.html#g499bb98a0b4ae9a98553ede81317606d">uip_ethaddr</a> = {{UIP_ETHADDR0,
<a name="l00129"></a>00129                                           UIP_ETHADDR1,
<a name="l00130"></a>00130                                           UIP_ETHADDR2,
<a name="l00131"></a>00131                                           UIP_ETHADDR3,
<a name="l00132"></a>00132                                           UIP_ETHADDR4,
<a name="l00133"></a>00133                                           UIP_ETHADDR5}};
<a name="l00134"></a>00134 <span class="preprocessor">#else</span>
<a name="l00135"></a><a class="code" href="a00152.html#g499bb98a0b4ae9a98553ede81317606d">00135</a> <span class="preprocessor"></span><span class="keyword">struct </span><a class="code" href="a00089.html">uip_eth_addr</a> <a class="code" href="a00150.html#g499bb98a0b4ae9a98553ede81317606d">uip_ethaddr</a> = {{0,0,0,0,0,0}};
<a name="l00136"></a>00136 <span class="preprocessor">#endif</span>
<a name="l00137"></a>00137 <span class="preprocessor"></span>
<a name="l00138"></a>00138 <span class="preprocessor">#ifndef UIP_CONF_EXTERNAL_BUFFER</span>
<a name="l00139"></a><a class="code" href="a00150.html#gb81e78f890dbbee50c533a9734b74fd9">00139</a> <span class="preprocessor"></span><a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> <a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00153.html#g3589822ecb9d9c4145209756396b8a6b">UIP_BUFSIZE</a> + 2];   <span class="comment">/* The packet buffer that contains</span>
<a name="l00140"></a>00140 <span class="comment">                                    incoming packets. */</span>
<a name="l00141"></a>00141 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_EXTERNAL_BUFFER */</span>
<a name="l00142"></a>00142 
<a name="l00143"></a><a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">00143</a> <span class="keywordtype">void</span> *<a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a>;               <span class="comment">/* The uip_appdata pointer points to</span>
<a name="l00144"></a>00144 <span class="comment">                                    application data. */</span>
<a name="l00145"></a><a class="code" href="a00150.html#ga05a3dde2048480fa3ab2a5961898d18">00145</a> <span class="keywordtype">void</span> *<a class="code" href="a00150.html#ga05a3dde2048480fa3ab2a5961898d18">uip_sappdata</a>;              <span class="comment">/* The uip_appdata pointer points to</span>
<a name="l00146"></a>00146 <span class="comment">                                    the application data which is to</span>
<a name="l00147"></a>00147 <span class="comment">                                    be sent. */</span>
<a name="l00148"></a>00148 <span class="preprocessor">#if UIP_URGDATA &gt; 0</span>
<a name="l00149"></a>00149 <span class="preprocessor"></span><span class="keywordtype">void</span> *uip_urgdata;               <span class="comment">/* The uip_urgdata pointer points to</span>
<a name="l00150"></a>00150 <span class="comment">                                    urgent data (out-of-band data), if</span>
<a name="l00151"></a>00151 <span class="comment">                                    present. */</span>
<a name="l00152"></a>00152 <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> uip_urglen, uip_surglen;
<a name="l00153"></a>00153 <span class="preprocessor">#endif </span><span class="comment">/* UIP_URGDATA &gt; 0 */</span>
<a name="l00154"></a>00154 
<a name="l00155"></a><a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">00155</a> <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>, <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a>;
<a name="l00156"></a>00156                              <span class="comment">/* The uip_len is either 8 or 16 bits,</span>
<a name="l00157"></a>00157 <span class="comment">                                depending on the maximum packet</span>
<a name="l00158"></a>00158 <span class="comment">                                size. */</span>
<a name="l00159"></a>00159 
<a name="l00160"></a><a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">00160</a> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a>;     <span class="comment">/* The uip_flags variable is used for</span>
<a name="l00161"></a>00161 <span class="comment">                                communication between the TCP/IP stack</span>
<a name="l00162"></a>00162 <span class="comment">                                and the application program. */</span>
<a name="l00163"></a><a class="code" href="a00150.html#g788ffac72342f6172343d7f8099cbe1a">00163</a> <span class="keyword">struct </span><a class="code" href="a00088.html">uip_conn</a> *<a class="code" href="a00088.html">uip_conn</a>;   <span class="comment">/* uip_conn always points to the current</span>
<a name="l00164"></a>00164 <span class="comment">                                connection. */</span>
<a name="l00165"></a>00165 
<a name="l00166"></a><a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">00166</a> <span class="keyword">struct </span><a class="code" href="a00150.html#g788ffac72342f6172343d7f8099cbe1a">uip_conn</a> <a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[<a class="code" href="a00153.html#gf5fe83be78b78b9e7d9e7f1e34ab1cc5">UIP_CONNS</a>];
<a name="l00167"></a>00167                              <span class="comment">/* The uip_conns array holds all TCP</span>
<a name="l00168"></a>00168 <span class="comment">                                connections. */</span>
<a name="l00169"></a><a class="code" href="a00150.html#g236d5c7872f59c8fe7b701c7252b976e">00169</a> <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> <a class="code" href="a00150.html#g236d5c7872f59c8fe7b701c7252b976e">uip_listenports</a>[<a class="code" href="a00153.html#g8f4ebd8ef6c0ea665ed351d87fec09fd">UIP_LISTENPORTS</a>];
<a name="l00170"></a>00170                              <span class="comment">/* The uip_listenports list all currently</span>
<a name="l00171"></a>00171 <span class="comment">                                listning ports. */</span>
<a name="l00172"></a>00172 <span class="preprocessor">#if UIP_UDP</span>
<a name="l00173"></a><a class="code" href="a00150.html#g210f227119fc972e6222c9cb452e15a9">00173</a> <span class="preprocessor"></span><span class="keyword">struct </span><a class="code" href="a00095.html">uip_udp_conn</a> *<a class="code" href="a00095.html">uip_udp_conn</a>;
<a name="l00174"></a><a class="code" href="a00150.html#geb533744817cf6695d75293369c2248b">00174</a> <span class="keyword">struct </span><a class="code" href="a00150.html#g210f227119fc972e6222c9cb452e15a9">uip_udp_conn</a> <a class="code" href="a00150.html#geb533744817cf6695d75293369c2248b">uip_udp_conns</a>[<a class="code" href="a00153.html#g196379ceb1219a99f4495e41ccc9bbfb">UIP_UDP_CONNS</a>];
<a name="l00175"></a>00175 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP */</span>
<a name="l00176"></a>00176 
<a name="l00177"></a>00177 <span class="keyword">static</span> <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> ipid;           <span class="comment">/* Ths ipid variable is an increasing</span>
<a name="l00178"></a>00178 <span class="comment">                                number that is used for the IP ID</span>
<a name="l00179"></a>00179 <span class="comment">                                field. */</span>
<a name="l00180"></a>00180 
<a name="l00181"></a><a class="code" href="a00150.html#g22f140b02c354dfebcc7ad481c3bcd68">00181</a> <span class="keywordtype">void</span> <a class="code" href="a00145.html#g22f140b02c354dfebcc7ad481c3bcd68">uip_setipid</a>(<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> <span class="keywordtype">id</span>) { ipid = id; }
<a name="l00182"></a>00182 
<a name="l00183"></a>00183 <span class="keyword">static</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> iss[4];          <span class="comment">/* The iss variable is used for the TCP</span>
<a name="l00184"></a>00184 <span class="comment">                                initial sequence number. */</span>
<a name="l00185"></a>00185 
<a name="l00186"></a>00186 <span class="preprocessor">#if UIP_ACTIVE_OPEN</span>
<a name="l00187"></a>00187 <span class="preprocessor"></span><span class="keyword">static</span> <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> lastport;       <span class="comment">/* Keeps track of the last port used for</span>
<a name="l00188"></a>00188 <span class="comment">                                a new connection. */</span>
<a name="l00189"></a>00189 <span class="preprocessor">#endif </span><span class="comment">/* UIP_ACTIVE_OPEN */</span>
<a name="l00190"></a>00190 
<a name="l00191"></a>00191 <span class="comment">/* Temporary variables. */</span>
<a name="l00192"></a><a class="code" href="a00150.html#g2a0cf5d86c58fab216414ce59bf1fea1">00192</a> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[4];
<a name="l00193"></a>00193 <span class="keyword">static</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> c, opt;
<a name="l00194"></a>00194 <span class="keyword">static</span> <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> tmp16;
<a name="l00195"></a>00195 
<a name="l00196"></a>00196 <span class="comment">/* Structures and definitions. */</span>
<a name="l00197"></a><a class="code" href="a00150.html#g88e60aa2cf23e1c65d630701db08c743">00197</a> <span class="preprocessor">#define TCP_FIN 0x01</span>
<a name="l00198"></a><a class="code" href="a00150.html#g6020613f5062417d9811cfa837215c83">00198</a> <span class="preprocessor"></span><span class="preprocessor">#define TCP_SYN 0x02</span>
<a name="l00199"></a><a class="code" href="a00150.html#g5ca559def464ef20d8b1f7d32f2f160d">00199</a> <span class="preprocessor"></span><span class="preprocessor">#define TCP_RST 0x04</span>
<a name="l00200"></a><a class="code" href="a00150.html#g1320fd0006a2f70138bc2d0018dda829">00200</a> <span class="preprocessor"></span><span class="preprocessor">#define TCP_PSH 0x08</span>
<a name="l00201"></a><a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">00201</a> <span class="preprocessor"></span><span class="preprocessor">#define TCP_ACK 0x10</span>
<a name="l00202"></a><a class="code" href="a00150.html#gc84f499cba8a02fc0e306c10b2acabf0">00202</a> <span class="preprocessor"></span><span class="preprocessor">#define TCP_URG 0x20</span>
<a name="l00203"></a><a class="code" href="a00150.html#g1425d4a0c2760adb653a04c0fb137a8d">00203</a> <span class="preprocessor"></span><span class="preprocessor">#define TCP_CTL 0x3f</span>
<a name="l00204"></a>00204 <span class="preprocessor"></span>
<a name="l00205"></a><a class="code" href="a00150.html#g1215163245304bad20d6c5608ad75ab7">00205</a> <span class="preprocessor">#define TCP_OPT_END     0   </span><span class="comment">/* End of TCP options list */</span>
<a name="l00206"></a><a class="code" href="a00150.html#g9f1822e1d231235edacad691f3cb7bbb">00206</a> <span class="preprocessor">#define TCP_OPT_NOOP    1   </span><span class="comment">/* "No-operation" TCP option */</span>
<a name="l00207"></a><a class="code" href="a00150.html#g691688604655ea8943d15f14c60027d8">00207</a> <span class="preprocessor">#define TCP_OPT_MSS     2   </span><span class="comment">/* Maximum segment size TCP option */</span>
<a name="l00208"></a>00208 
<a name="l00209"></a><a class="code" href="a00150.html#g12f3bf821224b8e7b48a57ed3cea15cf">00209</a> <span class="preprocessor">#define TCP_OPT_MSS_LEN 4   </span><span class="comment">/* Length of TCP MSS option. */</span>
<a name="l00210"></a>00210 
<a name="l00211"></a><a class="code" href="a00150.html#g5c5b1834e497f53ad0ef947bbe9777fa">00211</a> <span class="preprocessor">#define ICMP_ECHO_REPLY 0</span>
<a name="l00212"></a><a class="code" href="a00150.html#gd58231410d58e34b455328b888a9e73c">00212</a> <span class="preprocessor"></span><span class="preprocessor">#define ICMP_ECHO       8</span>
<a name="l00213"></a>00213 <span class="preprocessor"></span>
<a name="l00214"></a><a class="code" href="a00150.html#g207d17b633cd095120a74bc1f2257b17">00214</a> <span class="preprocessor">#define ICMP6_ECHO_REPLY             129</span>
<a name="l00215"></a><a class="code" href="a00150.html#g4cc3e223b63f27b546d62e9a258dba5a">00215</a> <span class="preprocessor"></span><span class="preprocessor">#define ICMP6_ECHO                   128</span>
<a name="l00216"></a><a class="code" href="a00150.html#g1cea57e3ea526f210b1068e6dcf7b4f4">00216</a> <span class="preprocessor"></span><span class="preprocessor">#define ICMP6_NEIGHBOR_SOLICITATION  135</span>
<a name="l00217"></a><a class="code" href="a00150.html#g62c03e0a308cc23929a80fe8d8f9dc1e">00217</a> <span class="preprocessor"></span><span class="preprocessor">#define ICMP6_NEIGHBOR_ADVERTISEMENT 136</span>
<a name="l00218"></a>00218 <span class="preprocessor"></span>
<a name="l00219"></a><a class="code" href="a00150.html#g1d3211dbbdfb22d6a47b60dddcf945e8">00219</a> <span class="preprocessor">#define ICMP6_FLAG_S (1 &lt;&lt; 6)</span>
<a name="l00220"></a>00220 <span class="preprocessor"></span>
<a name="l00221"></a><a class="code" href="a00150.html#g42288d5c3cf4b10becefec657f441e54">00221</a> <span class="preprocessor">#define ICMP6_OPTION_SOURCE_LINK_ADDRESS 1</span>
<a name="l00222"></a><a class="code" href="a00150.html#g8387881de3a8bfd3c0d57b9d04ac9b7e">00222</a> <span class="preprocessor"></span><span class="preprocessor">#define ICMP6_OPTION_TARGET_LINK_ADDRESS 2</span>
<a name="l00223"></a>00223 <span class="preprocessor"></span>
<a name="l00224"></a>00224 
<a name="l00225"></a>00225 <span class="comment">/* Macros. */</span>
<a name="l00226"></a><a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">00226</a> <span class="preprocessor">#define BUF ((struct uip_tcpip_hdr *)&amp;uip_buf[UIP_LLH_LEN])</span>
<a name="l00227"></a><a class="code" href="a00150.html#g96544dedc1cdc71ad2ad54bf1d5e5433">00227</a> <span class="preprocessor"></span><span class="preprocessor">#define FBUF ((struct uip_tcpip_hdr *)&amp;uip_reassbuf[0])</span>
<a name="l00228"></a><a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">00228</a> <span class="preprocessor"></span><span class="preprocessor">#define ICMPBUF ((struct uip_icmpip_hdr *)&amp;uip_buf[UIP_LLH_LEN])</span>
<a name="l00229"></a><a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">00229</a> <span class="preprocessor"></span><span class="preprocessor">#define UDPBUF ((struct uip_udpip_hdr *)&amp;uip_buf[UIP_LLH_LEN])</span>
<a name="l00230"></a>00230 <span class="preprocessor"></span>
<a name="l00231"></a>00231 
<a name="l00232"></a>00232 <span class="preprocessor">#if UIP_STATISTICS == 1</span>
<a name="l00233"></a>00233 <span class="preprocessor"></span><span class="keyword">struct </span><a class="code" href="a00093.html">uip_stats</a> <a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>;
<a name="l00234"></a>00234 <span class="preprocessor">#define UIP_STAT(s) s</span>
<a name="l00235"></a>00235 <span class="preprocessor"></span><span class="preprocessor">#else</span>
<a name="l00236"></a><a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">00236</a> <span class="preprocessor"></span><span class="preprocessor">#define UIP_STAT(s)</span>
<a name="l00237"></a>00237 <span class="preprocessor"></span><span class="preprocessor">#endif </span><span class="comment">/* UIP_STATISTICS == 1 */</span>
<a name="l00238"></a>00238 
<a name="l00239"></a>00239 <span class="preprocessor">#if UIP_LOGGING == 1</span>
<a name="l00240"></a>00240 <span class="preprocessor"></span><span class="preprocessor">#include &lt;stdio.h&gt;</span>
<a name="l00241"></a>00241 <span class="keywordtype">void</span> <a class="code" href="a00153.html#gb58e1ceb7cb73ca2bcd73146b6c1b4e7">uip_log</a>(<span class="keywordtype">char</span> *msg);
<a name="l00242"></a>00242 <span class="preprocessor">#define UIP_LOG(m) uip_log(m)</span>
<a name="l00243"></a>00243 <span class="preprocessor"></span><span class="preprocessor">#else</span>
<a name="l00244"></a><a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">00244</a> <span class="preprocessor"></span><span class="preprocessor">#define UIP_LOG(m)</span>
<a name="l00245"></a>00245 <span class="preprocessor"></span><span class="preprocessor">#endif </span><span class="comment">/* UIP_LOGGING == 1 */</span>
<a name="l00246"></a>00246 
<a name="l00247"></a>00247 <span class="preprocessor">#if ! UIP_ARCH_ADD32</span>
<a name="l00248"></a>00248 <span class="preprocessor"></span><span class="keywordtype">void</span>
<a name="l00249"></a><a class="code" href="a00151.html#g6832e4d2d046536b6472f7ac92340f68">00249</a> <a class="code" href="a00150.html#g6832e4d2d046536b6472f7ac92340f68">uip_add32</a>(<a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> *op32, <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> op16)
<a name="l00250"></a>00250 {
<a name="l00251"></a>00251   uip_acc32[3] = op32[3] + (op16 &amp; 0xff);
<a name="l00252"></a>00252   uip_acc32[2] = op32[2] + (op16 &gt;&gt; 8);
<a name="l00253"></a>00253   uip_acc32[1] = op32[1];
<a name="l00254"></a>00254   uip_acc32[0] = op32[0];
<a name="l00255"></a>00255   
<a name="l00256"></a>00256   <span class="keywordflow">if</span>(uip_acc32[2] &lt; (op16 &gt;&gt; 8)) {
<a name="l00257"></a>00257     ++uip_acc32[1];
<a name="l00258"></a>00258     <span class="keywordflow">if</span>(uip_acc32[1] == 0) {
<a name="l00259"></a>00259       ++uip_acc32[0];
<a name="l00260"></a>00260     }
<a name="l00261"></a>00261   }
<a name="l00262"></a>00262   
<a name="l00263"></a>00263   
<a name="l00264"></a>00264   <span class="keywordflow">if</span>(uip_acc32[3] &lt; (op16 &amp; 0xff)) {
<a name="l00265"></a>00265     ++uip_acc32[2];
<a name="l00266"></a>00266     <span class="keywordflow">if</span>(uip_acc32[2] == 0) {
<a name="l00267"></a>00267       ++uip_acc32[1];
<a name="l00268"></a>00268       <span class="keywordflow">if</span>(uip_acc32[1] == 0) {
<a name="l00269"></a>00269         ++uip_acc32[0];
<a name="l00270"></a>00270       }
<a name="l00271"></a>00271     }
<a name="l00272"></a>00272   }
<a name="l00273"></a>00273 }
<a name="l00274"></a>00274 
<a name="l00275"></a>00275 <span class="preprocessor">#endif </span><span class="comment">/* UIP_ARCH_ADD32 */</span>
<a name="l00276"></a>00276 
<a name="l00277"></a>00277 <span class="preprocessor">#if ! UIP_ARCH_CHKSUM</span>
<a name="l00278"></a>00278 <span class="preprocessor"></span><span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00279"></a>00279 <span class="keyword">static</span> <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>
<a name="l00280"></a>00280 chksum(<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> sum, <span class="keyword">const</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> *data, <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> len)
<a name="l00281"></a>00281 {
<a name="l00282"></a>00282   <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> t;
<a name="l00283"></a>00283   <span class="keyword">const</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> *dataptr;
<a name="l00284"></a>00284   <span class="keyword">const</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> *last_byte;
<a name="l00285"></a>00285 
<a name="l00286"></a>00286   dataptr = data;
<a name="l00287"></a>00287   last_byte = data + len - 1;
<a name="l00288"></a>00288   
<a name="l00289"></a>00289   <span class="keywordflow">while</span>(dataptr &lt; last_byte) {  <span class="comment">/* At least two more bytes */</span>
<a name="l00290"></a>00290     t = (dataptr[0] &lt;&lt; 8) + dataptr[1];
<a name="l00291"></a>00291     sum += t;
<a name="l00292"></a>00292     <span class="keywordflow">if</span>(sum &lt; t) {
<a name="l00293"></a>00293       sum++;            <span class="comment">/* carry */</span>
<a name="l00294"></a>00294     }
<a name="l00295"></a>00295     dataptr += 2;
<a name="l00296"></a>00296   }
<a name="l00297"></a>00297   
<a name="l00298"></a>00298   <span class="keywordflow">if</span>(dataptr == last_byte) {
<a name="l00299"></a>00299     t = (dataptr[0] &lt;&lt; 8) + 0;
<a name="l00300"></a>00300     sum += t;
<a name="l00301"></a>00301     <span class="keywordflow">if</span>(sum &lt; t) {
<a name="l00302"></a>00302       sum++;            <span class="comment">/* carry */</span>
<a name="l00303"></a>00303     }
<a name="l00304"></a>00304   }
<a name="l00305"></a>00305 
<a name="l00306"></a>00306   <span class="comment">/* Return sum in host byte order. */</span>
<a name="l00307"></a>00307   <span class="keywordflow">return</span> sum;
<a name="l00308"></a>00308 }
<a name="l00309"></a>00309 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00310"></a>00310 <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>
<a name="l00311"></a><a class="code" href="a00150.html#gb6683dd83fe1c8de9a24086d4b69e907">00311</a> <a class="code" href="a00150.html#gb6683dd83fe1c8de9a24086d4b69e907">uip_chksum</a>(<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> *data, <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> len)
<a name="l00312"></a>00312 {
<a name="l00313"></a>00313   <span class="keywordflow">return</span> <a class="code" href="a00148.html#ga22b04cac8cf283ca12f028578bebc06">htons</a>(chksum(0, (<a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> *)data, len));
<a name="l00314"></a>00314 }
<a name="l00315"></a>00315 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00316"></a>00316 <span class="preprocessor">#ifndef UIP_ARCH_IPCHKSUM</span>
<a name="l00317"></a>00317 <span class="preprocessor"></span><a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>
<a name="l00318"></a><a class="code" href="a00150.html#g2addf34c7d457c1a7899a7e2171ef1e9">00318</a> <a class="code" href="a00150.html#g2addf34c7d457c1a7899a7e2171ef1e9">uip_ipchksum</a>(<span class="keywordtype">void</span>)
<a name="l00319"></a>00319 {
<a name="l00320"></a>00320   <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> sum;
<a name="l00321"></a>00321 
<a name="l00322"></a>00322   sum = chksum(0, &amp;uip_buf[<a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a>], <a class="code" href="a00150.html#g6bc12c6c7b56f73ce5d57abfdcdc6eb5">UIP_IPH_LEN</a>);
<a name="l00323"></a>00323   <a class="code" href="a00135.html#534d9e416324fb8ecca6b9cb4b1f6a6a">DEBUG_PRINTF</a>(<span class="stringliteral">"uip_ipchksum: sum 0x%04x\n"</span>, sum);
<a name="l00324"></a>00324   <span class="keywordflow">return</span> (sum == 0) ? 0xffff : <a class="code" href="a00148.html#ga22b04cac8cf283ca12f028578bebc06">htons</a>(sum);
<a name="l00325"></a>00325 }
<a name="l00326"></a>00326 <span class="preprocessor">#endif</span>
<a name="l00327"></a>00327 <span class="preprocessor"></span><span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00328"></a>00328 <span class="keyword">static</span> <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>
<a name="l00329"></a>00329 upper_layer_chksum(<a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> proto)
<a name="l00330"></a>00330 {
<a name="l00331"></a>00331   <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> upper_layer_len;
<a name="l00332"></a>00332   <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> sum;
<a name="l00333"></a>00333   
<a name="l00334"></a>00334 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l00335"></a>00335 <span class="preprocessor"></span>  upper_layer_len = (((<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>)(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0]) &lt;&lt; 8) + <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1]);
<a name="l00336"></a>00336 <span class="preprocessor">#else </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00337"></a>00337   upper_layer_len = (((<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>)(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0]) &lt;&lt; 8) + <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1]) - <a class="code" href="a00150.html#g6bc12c6c7b56f73ce5d57abfdcdc6eb5">UIP_IPH_LEN</a>;
<a name="l00338"></a>00338 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00339"></a>00339   
<a name="l00340"></a>00340   <span class="comment">/* First sum pseudoheader. */</span>
<a name="l00341"></a>00341   
<a name="l00342"></a>00342   <span class="comment">/* IP protocol and length fields. This addition cannot carry. */</span>
<a name="l00343"></a>00343   sum = upper_layer_len + proto;
<a name="l00344"></a>00344   <span class="comment">/* Sum IP source and destination addresses. */</span>
<a name="l00345"></a>00345   sum = chksum(sum, (<a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> *)&amp;<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr[0], 2 * <span class="keyword">sizeof</span>(<a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a>));
<a name="l00346"></a>00346 
<a name="l00347"></a>00347   <span class="comment">/* Sum TCP header and data. */</span>
<a name="l00348"></a>00348   sum = chksum(sum, &amp;uip_buf[<a class="code" href="a00150.html#g6bc12c6c7b56f73ce5d57abfdcdc6eb5">UIP_IPH_LEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a>],
<a name="l00349"></a>00349                upper_layer_len);
<a name="l00350"></a>00350     
<a name="l00351"></a>00351   <span class="keywordflow">return</span> (sum == 0) ? 0xffff : <a class="code" href="a00148.html#ga22b04cac8cf283ca12f028578bebc06">htons</a>(sum);
<a name="l00352"></a>00352 }
<a name="l00353"></a>00353 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00354"></a>00354 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l00355"></a>00355 <span class="preprocessor"></span><a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>
<a name="l00356"></a>00356 uip_icmp6chksum(<span class="keywordtype">void</span>)
<a name="l00357"></a>00357 {
<a name="l00358"></a>00358   <span class="keywordflow">return</span> upper_layer_chksum(<a class="code" href="a00150.html#gad0321f4c570f9983c6de81ece3ddc20">UIP_PROTO_ICMP6</a>);
<a name="l00359"></a>00359   
<a name="l00360"></a>00360 }
<a name="l00361"></a>00361 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00362"></a>00362 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00363"></a>00363 <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>
<a name="l00364"></a><a class="code" href="a00150.html#g85b65e38aa74eba18979156f97a94a87">00364</a> <a class="code" href="a00150.html#g85b65e38aa74eba18979156f97a94a87">uip_tcpchksum</a>(<span class="keywordtype">void</span>)
<a name="l00365"></a>00365 {
<a name="l00366"></a>00366   <span class="keywordflow">return</span> upper_layer_chksum(<a class="code" href="a00150.html#g517c770991459cc62dc009c0d3875c6a">UIP_PROTO_TCP</a>);
<a name="l00367"></a>00367 }
<a name="l00368"></a>00368 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00369"></a>00369 <span class="preprocessor">#if UIP_UDP_CHECKSUMS</span>
<a name="l00370"></a>00370 <span class="preprocessor"></span><a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>
<a name="l00371"></a>00371 <a class="code" href="a00150.html#g7023a34ba9e9d03b5fbedbcb32924453">uip_udpchksum</a>(<span class="keywordtype">void</span>)
<a name="l00372"></a>00372 {
<a name="l00373"></a>00373   <span class="keywordflow">return</span> upper_layer_chksum(<a class="code" href="a00150.html#gf72d7b9a737707dcfb2c41fec2b6792e">UIP_PROTO_UDP</a>);
<a name="l00374"></a>00374 }
<a name="l00375"></a>00375 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP_CHECKSUMS */</span>
<a name="l00376"></a>00376 <span class="preprocessor">#endif </span><span class="comment">/* UIP_ARCH_CHKSUM */</span>
<a name="l00377"></a>00377 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00378"></a>00378 <span class="keywordtype">void</span>
<a name="l00379"></a><a class="code" href="a00150.html#gc48ed5f0d27721ef62a3ed02a5ad8d2e">00379</a> <a class="code" href="a00145.html#gc48ed5f0d27721ef62a3ed02a5ad8d2e">uip_init</a>(<span class="keywordtype">void</span>)
<a name="l00380"></a>00380 {
<a name="l00381"></a>00381   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#g8f4ebd8ef6c0ea665ed351d87fec09fd">UIP_LISTENPORTS</a>; ++c) {
<a name="l00382"></a>00382     uip_listenports[c] = 0;
<a name="l00383"></a>00383   }
<a name="l00384"></a>00384   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#gf5fe83be78b78b9e7d9e7f1e34ab1cc5">UIP_CONNS</a>; ++c) {
<a name="l00385"></a>00385     <a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[c].tcpstateflags = <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>;
<a name="l00386"></a>00386   }
<a name="l00387"></a>00387 <span class="preprocessor">#if UIP_ACTIVE_OPEN</span>
<a name="l00388"></a>00388 <span class="preprocessor"></span>  lastport = 1024;
<a name="l00389"></a>00389 <span class="preprocessor">#endif </span><span class="comment">/* UIP_ACTIVE_OPEN */</span>
<a name="l00390"></a>00390 
<a name="l00391"></a>00391 <span class="preprocessor">#if UIP_UDP</span>
<a name="l00392"></a>00392 <span class="preprocessor"></span>  <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#g196379ceb1219a99f4495e41ccc9bbfb">UIP_UDP_CONNS</a>; ++c) {
<a name="l00393"></a>00393     <a class="code" href="a00150.html#geb533744817cf6695d75293369c2248b">uip_udp_conns</a>[c].lport = 0;
<a name="l00394"></a>00394   }
<a name="l00395"></a>00395 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP */</span>
<a name="l00396"></a>00396   
<a name="l00397"></a>00397 
<a name="l00398"></a>00398   <span class="comment">/* IPv4 initialization. */</span>
<a name="l00399"></a>00399 <span class="preprocessor">#if UIP_FIXEDADDR == 0</span>
<a name="l00400"></a>00400 <span class="preprocessor"></span>  <span class="comment">/*  uip_hostaddr[0] = uip_hostaddr[1] = 0;*/</span>
<a name="l00401"></a>00401 <span class="preprocessor">#endif </span><span class="comment">/* UIP_FIXEDADDR */</span>
<a name="l00402"></a>00402 
<a name="l00403"></a>00403 }
<a name="l00404"></a>00404 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00405"></a>00405 <span class="preprocessor">#if UIP_ACTIVE_OPEN</span>
<a name="l00406"></a>00406 <span class="preprocessor"></span><span class="keyword">struct </span><a class="code" href="a00150.html#g788ffac72342f6172343d7f8099cbe1a">uip_conn</a> *
<a name="l00407"></a><a class="code" href="a00150.html#g9c24fba2cd8f7f62accb0a0d5bbe4dad">00407</a> <a class="code" href="a00147.html#g8096b0c4b543dc408f4dd031ddae7240">uip_connect</a>(<a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a> *<a class="code" href="a00088.html#79510aa86d3fa0a0fc6cfc49b1da7279">ripaddr</a>, <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> <a class="code" href="a00088.html#1df6aa054ef2fa634ac4c6f418228285">rport</a>)
<a name="l00408"></a>00408 {
<a name="l00409"></a>00409   <span class="keyword">register</span> <span class="keyword">struct </span><a class="code" href="a00150.html#g788ffac72342f6172343d7f8099cbe1a">uip_conn</a> *conn, *cconn;
<a name="l00410"></a>00410   
<a name="l00411"></a>00411   <span class="comment">/* Find an unused local port. */</span>
<a name="l00412"></a>00412  again:
<a name="l00413"></a>00413   ++lastport;
<a name="l00414"></a>00414 
<a name="l00415"></a>00415   <span class="keywordflow">if</span>(lastport &gt;= 32000) {
<a name="l00416"></a>00416     lastport = 4096;
<a name="l00417"></a>00417   }
<a name="l00418"></a>00418 
<a name="l00419"></a>00419   <span class="comment">/* Check if this port is already in use, and if so try to find</span>
<a name="l00420"></a>00420 <span class="comment">     another one. */</span>
<a name="l00421"></a>00421   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#gf5fe83be78b78b9e7d9e7f1e34ab1cc5">UIP_CONNS</a>; ++c) {
<a name="l00422"></a>00422     conn = &amp;<a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[c];
<a name="l00423"></a>00423     <span class="keywordflow">if</span>(conn-&gt;<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> != <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a> &amp;&amp;
<a name="l00424"></a>00424        conn-&gt;<a class="code" href="a00088.html#0cd09beee671e7e9efb0b4aced10249e">lport</a> == <a class="code" href="a00148.html#ga22b04cac8cf283ca12f028578bebc06">htons</a>(lastport)) {
<a name="l00425"></a>00425       <span class="keywordflow">goto</span> again;
<a name="l00426"></a>00426     }
<a name="l00427"></a>00427   }
<a name="l00428"></a>00428 
<a name="l00429"></a>00429   conn = 0;
<a name="l00430"></a>00430   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#gf5fe83be78b78b9e7d9e7f1e34ab1cc5">UIP_CONNS</a>; ++c) {
<a name="l00431"></a>00431     cconn = &amp;<a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[c];
<a name="l00432"></a>00432     <span class="keywordflow">if</span>(cconn-&gt;tcpstateflags == <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>) {
<a name="l00433"></a>00433       conn = cconn;
<a name="l00434"></a>00434       <span class="keywordflow">break</span>;
<a name="l00435"></a>00435     }
<a name="l00436"></a>00436     <span class="keywordflow">if</span>(cconn-&gt;tcpstateflags == <a class="code" href="a00150.html#gfff0ed43201bf1e2020de1a0d6cac070">UIP_TIME_WAIT</a>) {
<a name="l00437"></a>00437       <span class="keywordflow">if</span>(conn == 0 ||
<a name="l00438"></a>00438          cconn-&gt;timer &gt; conn-&gt;timer) {
<a name="l00439"></a>00439         conn = cconn;
<a name="l00440"></a>00440       }
<a name="l00441"></a>00441     }
<a name="l00442"></a>00442   }
<a name="l00443"></a>00443 
<a name="l00444"></a>00444   <span class="keywordflow">if</span>(conn == 0) {
<a name="l00445"></a>00445     <span class="keywordflow">return</span> 0;
<a name="l00446"></a>00446   }
<a name="l00447"></a>00447   
<a name="l00448"></a>00448   conn-&gt;<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> = <a class="code" href="a00150.html#g8af482dec973db57d8b3bd3f69461488">UIP_SYN_SENT</a>;
<a name="l00449"></a>00449 
<a name="l00450"></a>00450   conn-&gt;snd_nxt[0] = iss[0];
<a name="l00451"></a>00451   conn-&gt;snd_nxt[1] = iss[1];
<a name="l00452"></a>00452   conn-&gt;snd_nxt[2] = iss[2];
<a name="l00453"></a>00453   conn-&gt;snd_nxt[3] = iss[3];
<a name="l00454"></a>00454 
<a name="l00455"></a>00455   conn-&gt;initialmss = conn-&gt;mss = <a class="code" href="a00153.html#g4910467b83a639f06739c82cd362037e">UIP_TCP_MSS</a>;
<a name="l00456"></a>00456   
<a name="l00457"></a>00457   conn-&gt;len = 1;   <span class="comment">/* TCP length of the SYN is one. */</span>
<a name="l00458"></a>00458   conn-&gt;nrtx = 0;
<a name="l00459"></a>00459   conn-&gt;timer = 1; <span class="comment">/* Send the SYN next time around. */</span>
<a name="l00460"></a>00460   conn-&gt;rto = <a class="code" href="a00153.html#g15de27b044603284f68db05a378235a7">UIP_RTO</a>;
<a name="l00461"></a>00461   conn-&gt;sa = 0;
<a name="l00462"></a>00462   conn-&gt;sv = 16;   <span class="comment">/* Initial value of the RTT variance. */</span>
<a name="l00463"></a>00463   conn-&gt;lport = <a class="code" href="a00148.html#ga22b04cac8cf283ca12f028578bebc06">htons</a>(lastport);
<a name="l00464"></a>00464   conn-&gt;rport = <a class="code" href="a00088.html#1df6aa054ef2fa634ac4c6f418228285">rport</a>;
<a name="l00465"></a>00465   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(&amp;conn-&gt;ripaddr, <a class="code" href="a00088.html#79510aa86d3fa0a0fc6cfc49b1da7279">ripaddr</a>);
<a name="l00466"></a>00466   
<a name="l00467"></a>00467   <span class="keywordflow">return</span> conn;
<a name="l00468"></a>00468 }
<a name="l00469"></a>00469 <span class="preprocessor">#endif </span><span class="comment">/* UIP_ACTIVE_OPEN */</span>
<a name="l00470"></a>00470 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00471"></a>00471 <span class="preprocessor">#if UIP_UDP</span>
<a name="l00472"></a>00472 <span class="preprocessor"></span><span class="keyword">struct </span><a class="code" href="a00150.html#g210f227119fc972e6222c9cb452e15a9">uip_udp_conn</a> *
<a name="l00473"></a><a class="code" href="a00150.html#g79c4110211247df3fb30b8cf1c4c02af">00473</a> <a class="code" href="a00147.html#g79c4110211247df3fb30b8cf1c4c02af">uip_udp_new</a>(<a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a> *<a class="code" href="a00095.html#8a661a2d544100b82d0d14a1985083d5">ripaddr</a>, <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> <a class="code" href="a00095.html#280a0c2a93544e597f92bbacf36ee1dc">rport</a>)
<a name="l00474"></a>00474 {
<a name="l00475"></a>00475   <span class="keyword">register</span> <span class="keyword">struct </span><a class="code" href="a00150.html#g210f227119fc972e6222c9cb452e15a9">uip_udp_conn</a> *conn;
<a name="l00476"></a>00476   
<a name="l00477"></a>00477   <span class="comment">/* Find an unused local port. */</span>
<a name="l00478"></a>00478  again:
<a name="l00479"></a>00479   ++lastport;
<a name="l00480"></a>00480 
<a name="l00481"></a>00481   <span class="keywordflow">if</span>(lastport &gt;= 32000) {
<a name="l00482"></a>00482     lastport = 4096;
<a name="l00483"></a>00483   }
<a name="l00484"></a>00484   
<a name="l00485"></a>00485   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#g196379ceb1219a99f4495e41ccc9bbfb">UIP_UDP_CONNS</a>; ++c) {
<a name="l00486"></a>00486     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#geb533744817cf6695d75293369c2248b">uip_udp_conns</a>[c].<a class="code" href="a00095.html#981392e295db4d024eea95805c51c371">lport</a> == <a class="code" href="a00148.html#ga22b04cac8cf283ca12f028578bebc06">htons</a>(lastport)) {
<a name="l00487"></a>00487       <span class="keywordflow">goto</span> again;
<a name="l00488"></a>00488     }
<a name="l00489"></a>00489   }
<a name="l00490"></a>00490 
<a name="l00491"></a>00491 
<a name="l00492"></a>00492   conn = 0;
<a name="l00493"></a>00493   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#g196379ceb1219a99f4495e41ccc9bbfb">UIP_UDP_CONNS</a>; ++c) {
<a name="l00494"></a>00494     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#geb533744817cf6695d75293369c2248b">uip_udp_conns</a>[c].<a class="code" href="a00095.html#981392e295db4d024eea95805c51c371">lport</a> == 0) {
<a name="l00495"></a>00495       conn = &amp;<a class="code" href="a00150.html#geb533744817cf6695d75293369c2248b">uip_udp_conns</a>[c];
<a name="l00496"></a>00496       <span class="keywordflow">break</span>;
<a name="l00497"></a>00497     }
<a name="l00498"></a>00498   }
<a name="l00499"></a>00499 
<a name="l00500"></a>00500   <span class="keywordflow">if</span>(conn == 0) {
<a name="l00501"></a>00501     <span class="keywordflow">return</span> 0;
<a name="l00502"></a>00502   }
<a name="l00503"></a>00503   
<a name="l00504"></a>00504   conn-&gt;<a class="code" href="a00095.html#981392e295db4d024eea95805c51c371">lport</a> = <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(lastport);
<a name="l00505"></a>00505   conn-&gt;rport = <a class="code" href="a00095.html#280a0c2a93544e597f92bbacf36ee1dc">rport</a>;
<a name="l00506"></a>00506   <span class="keywordflow">if</span>(<a class="code" href="a00095.html#8a661a2d544100b82d0d14a1985083d5">ripaddr</a> == <a class="code" href="a00160.html#g070d2ce7b6bb7e5c05602aa8c308d0c4">NULL</a>) {
<a name="l00507"></a>00507     memset(conn-&gt;ripaddr, 0, <span class="keyword">sizeof</span>(<a class="code" href="a00150.html#g1ef35301f43a5bbb9f89f07b5a36b9a0">uip_ipaddr_t</a>));
<a name="l00508"></a>00508   } <span class="keywordflow">else</span> {
<a name="l00509"></a>00509     <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(&amp;conn-&gt;ripaddr, <a class="code" href="a00095.html#8a661a2d544100b82d0d14a1985083d5">ripaddr</a>);
<a name="l00510"></a>00510   }
<a name="l00511"></a>00511   conn-&gt;ttl = <a class="code" href="a00153.html#gb61381673de27f31848c5396bf0b338e">UIP_TTL</a>;
<a name="l00512"></a>00512   
<a name="l00513"></a>00513   <span class="keywordflow">return</span> conn;
<a name="l00514"></a>00514 }
<a name="l00515"></a>00515 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP */</span>
<a name="l00516"></a>00516 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00517"></a>00517 <span class="keywordtype">void</span>
<a name="l00518"></a><a class="code" href="a00150.html#gaa585784b0914cac1d37f07f85457008">00518</a> <a class="code" href="a00147.html#gaa585784b0914cac1d37f07f85457008">uip_unlisten</a>(<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> port)
<a name="l00519"></a>00519 {
<a name="l00520"></a>00520   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#g8f4ebd8ef6c0ea665ed351d87fec09fd">UIP_LISTENPORTS</a>; ++c) {
<a name="l00521"></a>00521     <span class="keywordflow">if</span>(uip_listenports[c] == port) {
<a name="l00522"></a>00522       uip_listenports[c] = 0;
<a name="l00523"></a>00523       <span class="keywordflow">return</span>;
<a name="l00524"></a>00524     }
<a name="l00525"></a>00525   }
<a name="l00526"></a>00526 }
<a name="l00527"></a>00527 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00528"></a>00528 <span class="keywordtype">void</span>
<a name="l00529"></a><a class="code" href="a00150.html#gdd1ab3704ecd4900eec61a6897d32dc8">00529</a> <a class="code" href="a00147.html#gdd1ab3704ecd4900eec61a6897d32dc8">uip_listen</a>(<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> port)
<a name="l00530"></a>00530 {
<a name="l00531"></a>00531   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#g8f4ebd8ef6c0ea665ed351d87fec09fd">UIP_LISTENPORTS</a>; ++c) {
<a name="l00532"></a>00532     <span class="keywordflow">if</span>(uip_listenports[c] == 0) {
<a name="l00533"></a>00533       uip_listenports[c] = port;
<a name="l00534"></a>00534       <span class="keywordflow">return</span>;
<a name="l00535"></a>00535     }
<a name="l00536"></a>00536   }
<a name="l00537"></a>00537 }
<a name="l00538"></a>00538 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00539"></a>00539 <span class="comment">/* XXX: IP fragment reassembly: not well-tested. */</span>
<a name="l00540"></a>00540 
<a name="l00541"></a>00541 <span class="preprocessor">#if UIP_REASSEMBLY &amp;&amp; !UIP_CONF_IPV6</span>
<a name="l00542"></a>00542 <span class="preprocessor"></span><span class="preprocessor">#define UIP_REASS_BUFSIZE (UIP_BUFSIZE - UIP_LLH_LEN)</span>
<a name="l00543"></a>00543 <span class="preprocessor"></span><span class="keyword">static</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> uip_reassbuf[UIP_REASS_BUFSIZE];
<a name="l00544"></a>00544 <span class="keyword">static</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> uip_reassbitmap[UIP_REASS_BUFSIZE / (8 * 8)];
<a name="l00545"></a>00545 <span class="keyword">static</span> <span class="keyword">const</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> bitmap_bits[8] = {0xff, 0x7f, 0x3f, 0x1f,
<a name="l00546"></a>00546                                     0x0f, 0x07, 0x03, 0x01};
<a name="l00547"></a>00547 <span class="keyword">static</span> <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> uip_reasslen;
<a name="l00548"></a>00548 <span class="keyword">static</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> uip_reassflags;
<a name="l00549"></a>00549 <span class="preprocessor">#define UIP_REASS_FLAG_LASTFRAG 0x01</span>
<a name="l00550"></a>00550 <span class="preprocessor"></span><span class="keyword">static</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> uip_reasstmr;
<a name="l00551"></a>00551 
<a name="l00552"></a>00552 <span class="preprocessor">#define IP_MF   0x20</span>
<a name="l00553"></a>00553 <span class="preprocessor"></span>
<a name="l00554"></a>00554 <span class="keyword">static</span> <a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a>
<a name="l00555"></a>00555 uip_reass(<span class="keywordtype">void</span>)
<a name="l00556"></a>00556 {
<a name="l00557"></a>00557   <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> offset, len;
<a name="l00558"></a>00558   <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> i;
<a name="l00559"></a>00559 
<a name="l00560"></a>00560   <span class="comment">/* If ip_reasstmr is zero, no packet is present in the buffer, so we</span>
<a name="l00561"></a>00561 <span class="comment">     write the IP header of the fragment into the reassembly</span>
<a name="l00562"></a>00562 <span class="comment">     buffer. The timer is updated with the maximum age. */</span>
<a name="l00563"></a>00563   <span class="keywordflow">if</span>(uip_reasstmr == 0) {
<a name="l00564"></a>00564     memcpy(uip_reassbuf, &amp;<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;vhl, <a class="code" href="a00150.html#g6bc12c6c7b56f73ce5d57abfdcdc6eb5">UIP_IPH_LEN</a>);
<a name="l00565"></a>00565     uip_reasstmr = <a class="code" href="a00153.html#gc3882366feda1cb759ccbfe98327a7db">UIP_REASS_MAXAGE</a>;
<a name="l00566"></a>00566     uip_reassflags = 0;
<a name="l00567"></a>00567     <span class="comment">/* Clear the bitmap. */</span>
<a name="l00568"></a>00568     memset(uip_reassbitmap, 0, <span class="keyword">sizeof</span>(uip_reassbitmap));
<a name="l00569"></a>00569   }
<a name="l00570"></a>00570 
<a name="l00571"></a>00571   <span class="comment">/* Check if the incoming fragment matches the one currently present</span>
<a name="l00572"></a>00572 <span class="comment">     in the reasembly buffer. If so, we proceed with copying the</span>
<a name="l00573"></a>00573 <span class="comment">     fragment into the buffer. */</span>
<a name="l00574"></a>00574   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr[0] == <a class="code" href="a00150.html#g96544dedc1cdc71ad2ad54bf1d5e5433">FBUF</a>-&gt;srcipaddr[0] &amp;&amp;
<a name="l00575"></a>00575      <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr[1] == <a class="code" href="a00150.html#g96544dedc1cdc71ad2ad54bf1d5e5433">FBUF</a>-&gt;srcipaddr[1] &amp;&amp;
<a name="l00576"></a>00576      <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr[0] == <a class="code" href="a00150.html#g96544dedc1cdc71ad2ad54bf1d5e5433">FBUF</a>-&gt;destipaddr[0] &amp;&amp;
<a name="l00577"></a>00577      <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr[1] == <a class="code" href="a00150.html#g96544dedc1cdc71ad2ad54bf1d5e5433">FBUF</a>-&gt;destipaddr[1] &amp;&amp;
<a name="l00578"></a>00578      <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipid[0] == <a class="code" href="a00150.html#g96544dedc1cdc71ad2ad54bf1d5e5433">FBUF</a>-&gt;ipid[0] &amp;&amp;
<a name="l00579"></a>00579      <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipid[1] == <a class="code" href="a00150.html#g96544dedc1cdc71ad2ad54bf1d5e5433">FBUF</a>-&gt;ipid[1]) {
<a name="l00580"></a>00580 
<a name="l00581"></a>00581     len = (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] &lt;&lt; 8) + <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1] - (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;vhl &amp; 0x0f) * 4;
<a name="l00582"></a>00582     offset = (((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[0] &amp; 0x3f) &lt;&lt; 8) + <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[1]) * 8;
<a name="l00583"></a>00583 
<a name="l00584"></a>00584     <span class="comment">/* If the offset or the offset + fragment length overflows the</span>
<a name="l00585"></a>00585 <span class="comment">       reassembly buffer, we discard the entire packet. */</span>
<a name="l00586"></a>00586     <span class="keywordflow">if</span>(offset &gt; UIP_REASS_BUFSIZE ||
<a name="l00587"></a>00587        offset + len &gt; UIP_REASS_BUFSIZE) {
<a name="l00588"></a>00588       uip_reasstmr = 0;
<a name="l00589"></a>00589       <span class="keywordflow">goto</span> nullreturn;
<a name="l00590"></a>00590     }
<a name="l00591"></a>00591 
<a name="l00592"></a>00592     <span class="comment">/* Copy the fragment into the reassembly buffer, at the right</span>
<a name="l00593"></a>00593 <span class="comment">       offset. */</span>
<a name="l00594"></a>00594     memcpy(&amp;uip_reassbuf[<a class="code" href="a00150.html#g6bc12c6c7b56f73ce5d57abfdcdc6eb5">UIP_IPH_LEN</a> + offset],
<a name="l00595"></a>00595            (<span class="keywordtype">char</span> *)<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a> + (<span class="keywordtype">int</span>)((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;vhl &amp; 0x0f) * 4),
<a name="l00596"></a>00596            len);
<a name="l00597"></a>00597       
<a name="l00598"></a>00598     <span class="comment">/* Update the bitmap. */</span>
<a name="l00599"></a>00599     <span class="keywordflow">if</span>(offset / (8 * 8) == (offset + len) / (8 * 8)) {
<a name="l00600"></a>00600       <span class="comment">/* If the two endpoints are in the same byte, we only update</span>
<a name="l00601"></a>00601 <span class="comment">         that byte. */</span>
<a name="l00602"></a>00602              
<a name="l00603"></a>00603       uip_reassbitmap[offset / (8 * 8)] |=
<a name="l00604"></a>00604              bitmap_bits[(offset / 8 ) &amp; 7] &amp;
<a name="l00605"></a>00605              ~bitmap_bits[((offset + len) / 8 ) &amp; 7];
<a name="l00606"></a>00606     } <span class="keywordflow">else</span> {
<a name="l00607"></a>00607       <span class="comment">/* If the two endpoints are in different bytes, we update the</span>
<a name="l00608"></a>00608 <span class="comment">         bytes in the endpoints and fill the stuff inbetween with</span>
<a name="l00609"></a>00609 <span class="comment">         0xff. */</span>
<a name="l00610"></a>00610       uip_reassbitmap[offset / (8 * 8)] |=
<a name="l00611"></a>00611         bitmap_bits[(offset / 8 ) &amp; 7];
<a name="l00612"></a>00612       <span class="keywordflow">for</span>(i = 1 + offset / (8 * 8); i &lt; (offset + len) / (8 * 8); ++i) {
<a name="l00613"></a>00613         uip_reassbitmap[i] = 0xff;
<a name="l00614"></a>00614       }
<a name="l00615"></a>00615       uip_reassbitmap[(offset + len) / (8 * 8)] |=
<a name="l00616"></a>00616         ~bitmap_bits[((offset + len) / 8 ) &amp; 7];
<a name="l00617"></a>00617     }
<a name="l00618"></a>00618     
<a name="l00619"></a>00619     <span class="comment">/* If this fragment has the More Fragments flag set to zero, we</span>
<a name="l00620"></a>00620 <span class="comment">       know that this is the last fragment, so we can calculate the</span>
<a name="l00621"></a>00621 <span class="comment">       size of the entire packet. We also set the</span>
<a name="l00622"></a>00622 <span class="comment">       IP_REASS_FLAG_LASTFRAG flag to indicate that we have received</span>
<a name="l00623"></a>00623 <span class="comment">       the final fragment. */</span>
<a name="l00624"></a>00624 
<a name="l00625"></a>00625     <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[0] &amp; IP_MF) == 0) {
<a name="l00626"></a>00626       uip_reassflags |= UIP_REASS_FLAG_LASTFRAG;
<a name="l00627"></a>00627       uip_reasslen = offset + len;
<a name="l00628"></a>00628     }
<a name="l00629"></a>00629     
<a name="l00630"></a>00630     <span class="comment">/* Finally, we check if we have a full packet in the buffer. We do</span>
<a name="l00631"></a>00631 <span class="comment">       this by checking if we have the last fragment and if all bits</span>
<a name="l00632"></a>00632 <span class="comment">       in the bitmap are set. */</span>
<a name="l00633"></a>00633     <span class="keywordflow">if</span>(uip_reassflags &amp; UIP_REASS_FLAG_LASTFRAG) {
<a name="l00634"></a>00634       <span class="comment">/* Check all bytes up to and including all but the last byte in</span>
<a name="l00635"></a>00635 <span class="comment">         the bitmap. */</span>
<a name="l00636"></a>00636       <span class="keywordflow">for</span>(i = 0; i &lt; uip_reasslen / (8 * 8) - 1; ++i) {
<a name="l00637"></a>00637         <span class="keywordflow">if</span>(uip_reassbitmap[i] != 0xff) {
<a name="l00638"></a>00638           <span class="keywordflow">goto</span> nullreturn;
<a name="l00639"></a>00639         }
<a name="l00640"></a>00640       }
<a name="l00641"></a>00641       <span class="comment">/* Check the last byte in the bitmap. It should contain just the</span>
<a name="l00642"></a>00642 <span class="comment">         right amount of bits. */</span>
<a name="l00643"></a>00643       <span class="keywordflow">if</span>(uip_reassbitmap[uip_reasslen / (8 * 8)] !=
<a name="l00644"></a>00644          (<a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a>)~bitmap_bits[uip_reasslen / 8 &amp; 7]) {
<a name="l00645"></a>00645         <span class="keywordflow">goto</span> nullreturn;
<a name="l00646"></a>00646       }
<a name="l00647"></a>00647 
<a name="l00648"></a>00648       <span class="comment">/* If we have come this far, we have a full packet in the</span>
<a name="l00649"></a>00649 <span class="comment">         buffer, so we allocate a pbuf and copy the packet into it. We</span>
<a name="l00650"></a>00650 <span class="comment">         also reset the timer. */</span>
<a name="l00651"></a>00651       uip_reasstmr = 0;
<a name="l00652"></a>00652       memcpy(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>, <a class="code" href="a00150.html#g96544dedc1cdc71ad2ad54bf1d5e5433">FBUF</a>, uip_reasslen);
<a name="l00653"></a>00653 
<a name="l00654"></a>00654       <span class="comment">/* Pretend to be a "normal" (i.e., not fragmented) IP packet</span>
<a name="l00655"></a>00655 <span class="comment">         from now on. */</span>
<a name="l00656"></a>00656       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[1] = 0;
<a name="l00657"></a>00657       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] = uip_reasslen &gt;&gt; 8;
<a name="l00658"></a>00658       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1] = uip_reasslen &amp; 0xff;
<a name="l00659"></a>00659       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipchksum = 0;
<a name="l00660"></a>00660       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipchksum = ~(<a class="code" href="a00150.html#g2addf34c7d457c1a7899a7e2171ef1e9">uip_ipchksum</a>());
<a name="l00661"></a>00661 
<a name="l00662"></a>00662       <span class="keywordflow">return</span> uip_reasslen;
<a name="l00663"></a>00663     }
<a name="l00664"></a>00664   }
<a name="l00665"></a>00665 
<a name="l00666"></a>00666  nullreturn:
<a name="l00667"></a>00667   <span class="keywordflow">return</span> 0;
<a name="l00668"></a>00668 }
<a name="l00669"></a>00669 <span class="preprocessor">#endif </span><span class="comment">/* UIP_REASSEMBLY */</span>
<a name="l00670"></a>00670 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00671"></a>00671 <span class="keyword">static</span> <span class="keywordtype">void</span>
<a name="l00672"></a>00672 uip_add_rcv_nxt(<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> n)
<a name="l00673"></a>00673 {
<a name="l00674"></a>00674   <a class="code" href="a00150.html#g6832e4d2d046536b6472f7ac92340f68">uip_add32</a>(<a class="code" href="a00088.html">uip_conn</a>-&gt;rcv_nxt, n);
<a name="l00675"></a>00675   <a class="code" href="a00088.html">uip_conn</a>-&gt;rcv_nxt[0] = <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[0];
<a name="l00676"></a>00676   <a class="code" href="a00088.html">uip_conn</a>-&gt;rcv_nxt[1] = <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[1];
<a name="l00677"></a>00677   <a class="code" href="a00088.html">uip_conn</a>-&gt;rcv_nxt[2] = <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[2];
<a name="l00678"></a>00678   <a class="code" href="a00088.html">uip_conn</a>-&gt;rcv_nxt[3] = <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[3];
<a name="l00679"></a>00679 }
<a name="l00680"></a>00680 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l00681"></a>00681 <span class="keywordtype">void</span>
<a name="l00682"></a><a class="code" href="a00150.html#g266263ac78a1361a2b1d15741d3b0675">00682</a> <a class="code" href="a00150.html#g266263ac78a1361a2b1d15741d3b0675">uip_process</a>(<a class="code" href="a00153.html#g4caecabca98b43919dd11be1c0d4cd8e">u8_t</a> flag)
<a name="l00683"></a>00683 {
<a name="l00684"></a>00684   <span class="keyword">register</span> <span class="keyword">struct </span><a class="code" href="a00088.html">uip_conn</a> *uip_connr = <a class="code" href="a00088.html">uip_conn</a>;
<a name="l00685"></a>00685 
<a name="l00686"></a>00686 <span class="preprocessor">#if UIP_UDP</span>
<a name="l00687"></a>00687 <span class="preprocessor"></span>  <span class="keywordflow">if</span>(flag == <a class="code" href="a00150.html#g5c97ae587595b5444be80f5ecc1d3382">UIP_UDP_SEND_CONN</a>) {
<a name="l00688"></a>00688     <span class="keywordflow">goto</span> udp_send;
<a name="l00689"></a>00689   }
<a name="l00690"></a>00690 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP */</span>
<a name="l00691"></a>00691   
<a name="l00692"></a>00692   <a class="code" href="a00150.html#ga05a3dde2048480fa3ab2a5961898d18">uip_sappdata</a> = <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a> = &amp;<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#g15f2617f7dc1713f9d10282125c6027b">UIP_IPTCPH_LEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a>];
<a name="l00693"></a>00693 
<a name="l00694"></a>00694   <span class="comment">/* Check if we were invoked because of a poll request for a</span>
<a name="l00695"></a>00695 <span class="comment">     particular connection. */</span>
<a name="l00696"></a>00696   <span class="keywordflow">if</span>(flag == <a class="code" href="a00150.html#gd605357e29affb0d3104294c90f09905">UIP_POLL_REQUEST</a>) {
<a name="l00697"></a>00697     <span class="keywordflow">if</span>((uip_connr-&gt;<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> &amp; <a class="code" href="a00150.html#g13dfcb4a5f920e108253ade527a66cc2">UIP_TS_MASK</a>) == <a class="code" href="a00150.html#gae59b70658f28ee6e998eaaab05e423f">UIP_ESTABLISHED</a> &amp;&amp;
<a name="l00698"></a>00698        !<a class="code" href="a00147.html#gef14e83c046e19ab9fe9d1bbcca276c2">uip_outstanding</a>(uip_connr)) {
<a name="l00699"></a>00699         <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#gf0ed78fd2be24d849cdd5af75e3b2674">UIP_POLL</a>;
<a name="l00700"></a>00700         <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l00701"></a>00701         <span class="keywordflow">goto</span> appsend;
<a name="l00702"></a>00702     }
<a name="l00703"></a>00703     <span class="keywordflow">goto</span> drop;
<a name="l00704"></a>00704     
<a name="l00705"></a>00705     <span class="comment">/* Check if we were invoked because of the perodic timer fireing. */</span>
<a name="l00706"></a>00706   } <span class="keywordflow">else</span> <span class="keywordflow">if</span>(flag == <a class="code" href="a00150.html#g041aea91aa6ef84dcc6cac3c51db9b2f">UIP_TIMER</a>) {
<a name="l00707"></a>00707 <span class="preprocessor">#if UIP_REASSEMBLY</span>
<a name="l00708"></a>00708 <span class="preprocessor"></span>    <span class="keywordflow">if</span>(uip_reasstmr != 0) {
<a name="l00709"></a>00709       --uip_reasstmr;
<a name="l00710"></a>00710     }
<a name="l00711"></a>00711 <span class="preprocessor">#endif </span><span class="comment">/* UIP_REASSEMBLY */</span>
<a name="l00712"></a>00712     <span class="comment">/* Increase the initial sequence number. */</span>
<a name="l00713"></a>00713     <span class="keywordflow">if</span>(++iss[3] == 0) {
<a name="l00714"></a>00714       <span class="keywordflow">if</span>(++iss[2] == 0) {
<a name="l00715"></a>00715         <span class="keywordflow">if</span>(++iss[1] == 0) {
<a name="l00716"></a>00716           ++iss[0];
<a name="l00717"></a>00717         }
<a name="l00718"></a>00718       }
<a name="l00719"></a>00719     }
<a name="l00720"></a>00720 
<a name="l00721"></a>00721     <span class="comment">/* Reset the length variables. */</span>
<a name="l00722"></a>00722     <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = 0;
<a name="l00723"></a>00723     <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = 0;
<a name="l00724"></a>00724 
<a name="l00725"></a>00725     <span class="comment">/* Check if the connection is in a state in which we simply wait</span>
<a name="l00726"></a>00726 <span class="comment">       for the connection to time out. If so, we increase the</span>
<a name="l00727"></a>00727 <span class="comment">       connection's timer and remove the connection if it times</span>
<a name="l00728"></a>00728 <span class="comment">       out. */</span>
<a name="l00729"></a>00729     <span class="keywordflow">if</span>(uip_connr-&gt;<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> == <a class="code" href="a00150.html#gfff0ed43201bf1e2020de1a0d6cac070">UIP_TIME_WAIT</a> ||
<a name="l00730"></a>00730        uip_connr-&gt;<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> == <a class="code" href="a00150.html#g160128ab5d2ea3cc497b91ee4eb4ef99">UIP_FIN_WAIT_2</a>) {
<a name="l00731"></a>00731       ++(uip_connr-&gt;<a class="code" href="a00088.html#2d9732cf5752d30bd11cb25dc7d0c8d3">timer</a>);
<a name="l00732"></a>00732       <span class="keywordflow">if</span>(uip_connr-&gt;<a class="code" href="a00088.html#2d9732cf5752d30bd11cb25dc7d0c8d3">timer</a> == <a class="code" href="a00153.html#g2bc3b489923793759526a3181eb667fa">UIP_TIME_WAIT_TIMEOUT</a>) {
<a name="l00733"></a>00733         uip_connr-&gt;<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> = <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>;
<a name="l00734"></a>00734       }
<a name="l00735"></a>00735     } <span class="keywordflow">else</span> <span class="keywordflow">if</span>(uip_connr-&gt;<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> != <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>) {
<a name="l00736"></a>00736       <span class="comment">/* If the connection has outstanding data, we increase the</span>
<a name="l00737"></a>00737 <span class="comment">         connection's timer and see if it has reached the RTO value</span>
<a name="l00738"></a>00738 <span class="comment">         in which case we retransmit. */</span>
<a name="l00739"></a>00739       <span class="keywordflow">if</span>(<a class="code" href="a00147.html#gef14e83c046e19ab9fe9d1bbcca276c2">uip_outstanding</a>(uip_connr)) {
<a name="l00740"></a>00740         <span class="keywordflow">if</span>(uip_connr-&gt;timer-- == 0) {
<a name="l00741"></a>00741           <span class="keywordflow">if</span>(uip_connr-&gt;nrtx == <a class="code" href="a00153.html#g67cf1e0d2324c93f332c1f020c0fe8b3">UIP_MAXRTX</a> ||
<a name="l00742"></a>00742              ((uip_connr-&gt;tcpstateflags == <a class="code" href="a00150.html#g8af482dec973db57d8b3bd3f69461488">UIP_SYN_SENT</a> ||
<a name="l00743"></a>00743                uip_connr-&gt;tcpstateflags == <a class="code" href="a00150.html#ga5e3c856b86725125d19fccc34cd9eb5">UIP_SYN_RCVD</a>) &amp;&amp;
<a name="l00744"></a>00744               uip_connr-&gt;nrtx == <a class="code" href="a00153.html#g24aa5bc36939cc9a0833e1df01478a7e">UIP_MAXSYNRTX</a>)) {
<a name="l00745"></a>00745             uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>;
<a name="l00746"></a>00746 
<a name="l00747"></a>00747             <span class="comment">/* We call UIP_APPCALL() with uip_flags set to</span>
<a name="l00748"></a>00748 <span class="comment">               UIP_TIMEDOUT to inform the application that the</span>
<a name="l00749"></a>00749 <span class="comment">               connection has timed out. */</span>
<a name="l00750"></a>00750             <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#g2d3ba4b14d6d2f6576f9b547800b7945">UIP_TIMEDOUT</a>;
<a name="l00751"></a>00751             <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l00752"></a>00752 
<a name="l00753"></a>00753             <span class="comment">/* We also send a reset packet to the remote host. */</span>
<a name="l00754"></a>00754             <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g5ca559def464ef20d8b1f7d32f2f160d">TCP_RST</a> | <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l00755"></a>00755             <span class="keywordflow">goto</span> tcp_send_nodata;
<a name="l00756"></a>00756           }
<a name="l00757"></a>00757 
<a name="l00758"></a>00758           <span class="comment">/* Exponential backoff. */</span>
<a name="l00759"></a>00759           uip_connr-&gt;timer = <a class="code" href="a00153.html#g15de27b044603284f68db05a378235a7">UIP_RTO</a> &lt;&lt; (uip_connr-&gt;nrtx &gt; 4?
<a name="l00760"></a>00760                                          4:
<a name="l00761"></a>00761                                          uip_connr-&gt;nrtx);
<a name="l00762"></a>00762           ++(uip_connr-&gt;nrtx);
<a name="l00763"></a>00763           
<a name="l00764"></a>00764           <span class="comment">/* Ok, so we need to retransmit. We do this differently</span>
<a name="l00765"></a>00765 <span class="comment">             depending on which state we are in. In ESTABLISHED, we</span>
<a name="l00766"></a>00766 <span class="comment">             call upon the application so that it may prepare the</span>
<a name="l00767"></a>00767 <span class="comment">             data for the retransmit. In SYN_RCVD, we resend the</span>
<a name="l00768"></a>00768 <span class="comment">             SYNACK that we sent earlier and in LAST_ACK we have to</span>
<a name="l00769"></a>00769 <span class="comment">             retransmit our FINACK. */</span>
<a name="l00770"></a>00770           <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#e292b8977f6b81265bf14e1676face3e">tcp</a>.<a class="code" href="a00093.html#3ad48284f7a91f78bb24096aad89056e">rexmit</a>);
<a name="l00771"></a>00771           <span class="keywordflow">switch</span>(uip_connr-&gt;tcpstateflags &amp; <a class="code" href="a00150.html#g13dfcb4a5f920e108253ade527a66cc2">UIP_TS_MASK</a>) {
<a name="l00772"></a>00772           <span class="keywordflow">case</span> <a class="code" href="a00150.html#ga5e3c856b86725125d19fccc34cd9eb5">UIP_SYN_RCVD</a>:
<a name="l00773"></a>00773             <span class="comment">/* In the SYN_RCVD state, we should retransmit our</span>
<a name="l00774"></a>00774 <span class="comment">               SYNACK. */</span>
<a name="l00775"></a>00775             <span class="keywordflow">goto</span> tcp_send_synack;
<a name="l00776"></a>00776             
<a name="l00777"></a>00777 <span class="preprocessor">#if UIP_ACTIVE_OPEN</span>
<a name="l00778"></a>00778 <span class="preprocessor"></span>          <span class="keywordflow">case</span> <a class="code" href="a00150.html#g8af482dec973db57d8b3bd3f69461488">UIP_SYN_SENT</a>:
<a name="l00779"></a>00779             <span class="comment">/* In the SYN_SENT state, we retransmit out SYN. */</span>
<a name="l00780"></a>00780             <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = 0;
<a name="l00781"></a>00781             <span class="keywordflow">goto</span> tcp_send_syn;
<a name="l00782"></a>00782 <span class="preprocessor">#endif </span><span class="comment">/* UIP_ACTIVE_OPEN */</span>
<a name="l00783"></a>00783             
<a name="l00784"></a>00784           <span class="keywordflow">case</span> <a class="code" href="a00150.html#gae59b70658f28ee6e998eaaab05e423f">UIP_ESTABLISHED</a>:
<a name="l00785"></a>00785             <span class="comment">/* In the ESTABLISHED state, we call upon the application</span>
<a name="l00786"></a>00786 <span class="comment">               to do the actual retransmit after which we jump into</span>
<a name="l00787"></a>00787 <span class="comment">               the code for sending out the packet (the apprexmit</span>
<a name="l00788"></a>00788 <span class="comment">               label). */</span>
<a name="l00789"></a>00789             <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#gf848ce44c810492e7a35c2d23a429f45">UIP_REXMIT</a>;
<a name="l00790"></a>00790             <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l00791"></a>00791             <span class="keywordflow">goto</span> apprexmit;
<a name="l00792"></a>00792             
<a name="l00793"></a>00793           <span class="keywordflow">case</span> <a class="code" href="a00150.html#ga533c394b1fa0030205534befa31c525">UIP_FIN_WAIT_1</a>:
<a name="l00794"></a>00794           <span class="keywordflow">case</span> <a class="code" href="a00150.html#g64d9affc680a445d708234e70450477b">UIP_CLOSING</a>:
<a name="l00795"></a>00795           <span class="keywordflow">case</span> <a class="code" href="a00150.html#gd135fb0cfdfb2c212f0f51865a3640e4">UIP_LAST_ACK</a>:
<a name="l00796"></a>00796             <span class="comment">/* In all these states we should retransmit a FINACK. */</span>
<a name="l00797"></a>00797             <span class="keywordflow">goto</span> tcp_send_finack;
<a name="l00798"></a>00798             
<a name="l00799"></a>00799           }
<a name="l00800"></a>00800         }
<a name="l00801"></a>00801       } <span class="keywordflow">else</span> <span class="keywordflow">if</span>((uip_connr-&gt;tcpstateflags &amp; <a class="code" href="a00150.html#g13dfcb4a5f920e108253ade527a66cc2">UIP_TS_MASK</a>) == <a class="code" href="a00150.html#gae59b70658f28ee6e998eaaab05e423f">UIP_ESTABLISHED</a>) {
<a name="l00802"></a>00802         <span class="comment">/* If there was no need for a retransmission, we poll the</span>
<a name="l00803"></a>00803 <span class="comment">           application for new data. */</span>
<a name="l00804"></a>00804         <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#gf0ed78fd2be24d849cdd5af75e3b2674">UIP_POLL</a>;
<a name="l00805"></a>00805         <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l00806"></a>00806         <span class="keywordflow">goto</span> appsend;
<a name="l00807"></a>00807       }
<a name="l00808"></a>00808     }
<a name="l00809"></a>00809     <span class="keywordflow">goto</span> drop;
<a name="l00810"></a>00810   }
<a name="l00811"></a>00811 <span class="preprocessor">#if UIP_UDP</span>
<a name="l00812"></a>00812 <span class="preprocessor"></span>  <span class="keywordflow">if</span>(flag == <a class="code" href="a00150.html#gf0ccbc3bb2a3ba1ebc255c7b3fcedd24">UIP_UDP_TIMER</a>) {
<a name="l00813"></a>00813     <span class="keywordflow">if</span>(<a class="code" href="a00095.html">uip_udp_conn</a>-&gt;lport != 0) {
<a name="l00814"></a>00814       <a class="code" href="a00088.html">uip_conn</a> = <a class="code" href="a00160.html#g070d2ce7b6bb7e5c05602aa8c308d0c4">NULL</a>;
<a name="l00815"></a>00815       <a class="code" href="a00150.html#ga05a3dde2048480fa3ab2a5961898d18">uip_sappdata</a> = <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a> = &amp;<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + <a class="code" href="a00150.html#g6f2b90c597ec23f39ec716ccec11233c">UIP_IPUDPH_LEN</a>];
<a name="l00816"></a>00816       <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = 0;
<a name="l00817"></a>00817       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#gf0ed78fd2be24d849cdd5af75e3b2674">UIP_POLL</a>;
<a name="l00818"></a>00818       <a class="code" href="a00160.html#g3d768e989e308144190ae1a5ddfa9726">UIP_UDP_APPCALL</a>();
<a name="l00819"></a>00819       <span class="keywordflow">goto</span> udp_send;
<a name="l00820"></a>00820     } <span class="keywordflow">else</span> {
<a name="l00821"></a>00821       <span class="keywordflow">goto</span> drop;
<a name="l00822"></a>00822     }
<a name="l00823"></a>00823   }
<a name="l00824"></a>00824 <span class="preprocessor">#endif</span>
<a name="l00825"></a>00825 <span class="preprocessor"></span>
<a name="l00826"></a>00826   <span class="comment">/* This is where the input processing starts. */</span>
<a name="l00827"></a>00827   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#7f7bb2145afba5df00c6e10ddefa8ae1">recv</a>);
<a name="l00828"></a>00828 
<a name="l00829"></a>00829   <span class="comment">/* Start of IP input header processing code. */</span>
<a name="l00830"></a>00830   
<a name="l00831"></a>00831 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l00832"></a>00832 <span class="preprocessor"></span>  <span class="comment">/* Check validity of the IP header. */</span>
<a name="l00833"></a>00833   <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;vtc &amp; 0xf0) != 0x60)  { <span class="comment">/* IP version and header length. */</span>
<a name="l00834"></a>00834     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l00835"></a>00835     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#b93e351c3abba0c700b26b7b07e9527d">vhlerr</a>);
<a name="l00836"></a>00836     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ipv6: invalid version."</span>);
<a name="l00837"></a>00837     <span class="keywordflow">goto</span> drop;
<a name="l00838"></a>00838   }
<a name="l00839"></a>00839 <span class="preprocessor">#else </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00840"></a>00840   <span class="comment">/* Check validity of the IP header. */</span>
<a name="l00841"></a>00841   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;vhl != 0x45)  { <span class="comment">/* IP version and header length. */</span>
<a name="l00842"></a>00842     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l00843"></a>00843     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#b93e351c3abba0c700b26b7b07e9527d">vhlerr</a>);
<a name="l00844"></a>00844     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ip: invalid version or header length."</span>);
<a name="l00845"></a>00845     <span class="keywordflow">goto</span> drop;
<a name="l00846"></a>00846   }
<a name="l00847"></a>00847 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00848"></a>00848   
<a name="l00849"></a>00849   <span class="comment">/* Check the size of the packet. If the size reported to us in</span>
<a name="l00850"></a>00850 <span class="comment">     uip_len is smaller the size reported in the IP header, we assume</span>
<a name="l00851"></a>00851 <span class="comment">     that the packet has been corrupted in transit. If the size of</span>
<a name="l00852"></a>00852 <span class="comment">     uip_len is larger than the size reported in the IP packet header,</span>
<a name="l00853"></a>00853 <span class="comment">     the packet has been padded and we set uip_len to the correct</span>
<a name="l00854"></a>00854 <span class="comment">     value.. */</span>
<a name="l00855"></a>00855 
<a name="l00856"></a>00856   <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] &lt;&lt; 8) + <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1] &lt;= <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>) {
<a name="l00857"></a>00857     <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] &lt;&lt; 8) + <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1];
<a name="l00858"></a>00858 #<span class="keywordflow">if</span> UIP_CONF_IPV6
<a name="l00859"></a>00859     <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> += 40; <span class="comment">/* The length reported in the IPv6 header is the</span>
<a name="l00860"></a>00860 <span class="comment">                      length of the payload that follows the</span>
<a name="l00861"></a>00861 <span class="comment">                      header. However, uIP uses the uip_len variable</span>
<a name="l00862"></a>00862 <span class="comment">                      for holding the size of the entire packet,</span>
<a name="l00863"></a>00863 <span class="comment">                      including the IP header. For IPv4 this is not a</span>
<a name="l00864"></a>00864 <span class="comment">                      problem as the length field in the IPv4 header</span>
<a name="l00865"></a>00865 <span class="comment">                      contains the length of the entire packet. But</span>
<a name="l00866"></a>00866 <span class="comment">                      for IPv6 we need to add the size of the IPv6</span>
<a name="l00867"></a>00867 <span class="comment">                      header (40 bytes). */</span>
<a name="l00868"></a>00868 #endif <span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00869"></a>00869   } <span class="keywordflow">else</span> {
<a name="l00870"></a>00870     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ip: packet shorter than reported in IP header."</span>);
<a name="l00871"></a>00871     <span class="keywordflow">goto</span> drop;
<a name="l00872"></a>00872   }
<a name="l00873"></a>00873 
<a name="l00874"></a>00874 <span class="preprocessor">#if !UIP_CONF_IPV6</span>
<a name="l00875"></a>00875 <span class="preprocessor"></span>  <span class="comment">/* Check the fragment flag. */</span>
<a name="l00876"></a>00876   <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[0] &amp; 0x3f) != 0 ||
<a name="l00877"></a>00877      <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[1] != 0) {
<a name="l00878"></a>00878 <span class="preprocessor">#if UIP_REASSEMBLY</span>
<a name="l00879"></a>00879 <span class="preprocessor"></span>    <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = uip_reass();
<a name="l00880"></a>00880     <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> == 0) {
<a name="l00881"></a>00881       <span class="keywordflow">goto</span> drop;
<a name="l00882"></a>00882     }
<a name="l00883"></a>00883 <span class="preprocessor">#else </span><span class="comment">/* UIP_REASSEMBLY */</span>
<a name="l00884"></a>00884     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l00885"></a>00885     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#8082509468b2ac80ed7746aa1a5bc4f7">fragerr</a>);
<a name="l00886"></a>00886     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ip: fragment dropped."</span>);
<a name="l00887"></a>00887     <span class="keywordflow">goto</span> drop;
<a name="l00888"></a>00888 <span class="preprocessor">#endif </span><span class="comment">/* UIP_REASSEMBLY */</span>
<a name="l00889"></a>00889   }
<a name="l00890"></a>00890 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00891"></a>00891 
<a name="l00892"></a>00892   <span class="keywordflow">if</span>(<a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>, all_zeroes_addr)) {
<a name="l00893"></a>00893     <span class="comment">/* If we are configured to use ping IP address configuration and</span>
<a name="l00894"></a>00894 <span class="comment">       hasn't been assigned an IP address yet, we accept all ICMP</span>
<a name="l00895"></a>00895 <span class="comment">       packets. */</span>
<a name="l00896"></a>00896 <span class="preprocessor">#if UIP_PINGADDRCONF &amp;&amp; !UIP_CONF_IPV6</span>
<a name="l00897"></a>00897 <span class="preprocessor"></span>    <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;proto == <a class="code" href="a00150.html#g359951eecd80541c2101f628a9da9146">UIP_PROTO_ICMP</a>) {
<a name="l00898"></a>00898       <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ip: possible ping config packet received."</span>);
<a name="l00899"></a>00899       <span class="keywordflow">goto</span> icmp_input;
<a name="l00900"></a>00900     } <span class="keywordflow">else</span> {
<a name="l00901"></a>00901       <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ip: packet dropped since no address assigned."</span>);
<a name="l00902"></a>00902       <span class="keywordflow">goto</span> drop;
<a name="l00903"></a>00903     }
<a name="l00904"></a>00904 <span class="preprocessor">#endif </span><span class="comment">/* UIP_PINGADDRCONF */</span>
<a name="l00905"></a>00905 
<a name="l00906"></a>00906   } <span class="keywordflow">else</span> {
<a name="l00907"></a>00907     <span class="comment">/* If IP broadcast support is configured, we check for a broadcast</span>
<a name="l00908"></a>00908 <span class="comment">       UDP packet, which may be destined to us. */</span>
<a name="l00909"></a>00909 <span class="preprocessor">#if UIP_BROADCAST</span>
<a name="l00910"></a>00910 <span class="preprocessor"></span>    <a class="code" href="a00135.html#534d9e416324fb8ecca6b9cb4b1f6a6a">DEBUG_PRINTF</a>(<span class="stringliteral">"UDP IP checksum 0x%04x\n"</span>, <a class="code" href="a00150.html#g2addf34c7d457c1a7899a7e2171ef1e9">uip_ipchksum</a>());
<a name="l00911"></a>00911     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;proto == <a class="code" href="a00150.html#gf72d7b9a737707dcfb2c41fec2b6792e">UIP_PROTO_UDP</a> &amp;&amp;
<a name="l00912"></a>00912        <a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr, all_ones_addr)
<a name="l00913"></a>00913        <span class="comment">/*&amp;&amp;</span>
<a name="l00914"></a>00914 <span class="comment">         uip_ipchksum() == 0xffff*/</span>) {
<a name="l00915"></a>00915       <span class="keywordflow">goto</span> udp_input;
<a name="l00916"></a>00916     }
<a name="l00917"></a>00917 <span class="preprocessor">#endif </span><span class="comment">/* UIP_BROADCAST */</span>
<a name="l00918"></a>00918     
<a name="l00919"></a>00919     <span class="comment">/* Check if the packet is destined for our IP address. */</span>
<a name="l00920"></a>00920 <span class="preprocessor">#if !UIP_CONF_IPV6</span>
<a name="l00921"></a>00921 <span class="preprocessor"></span>    <span class="keywordflow">if</span>(!<a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>)) {
<a name="l00922"></a>00922       <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l00923"></a>00923       <span class="keywordflow">goto</span> drop;
<a name="l00924"></a>00924     }
<a name="l00925"></a>00925 <span class="preprocessor">#else </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00926"></a>00926     <span class="comment">/* For IPv6, packet reception is a little trickier as we need to</span>
<a name="l00927"></a>00927 <span class="comment">       make sure that we listen to certain multicast addresses (all</span>
<a name="l00928"></a>00928 <span class="comment">       hosts multicast address, and the solicited-node multicast</span>
<a name="l00929"></a>00929 <span class="comment">       address) as well. However, we will cheat here and accept all</span>
<a name="l00930"></a>00930 <span class="comment">       multicast packets that are sent to the ff02::/16 addresses. */</span>
<a name="l00931"></a>00931     <span class="keywordflow">if</span>(!<a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>) &amp;&amp;
<a name="l00932"></a>00932        <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr[0] != <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(0xff02)) {
<a name="l00933"></a>00933       <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l00934"></a>00934       <span class="keywordflow">goto</span> drop;
<a name="l00935"></a>00935     }
<a name="l00936"></a>00936 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00937"></a>00937   }
<a name="l00938"></a>00938 
<a name="l00939"></a>00939 <span class="preprocessor">#if !UIP_CONF_IPV6</span>
<a name="l00940"></a>00940 <span class="preprocessor"></span>  <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g2addf34c7d457c1a7899a7e2171ef1e9">uip_ipchksum</a>() != 0xffff) { <span class="comment">/* Compute and check the IP header</span>
<a name="l00941"></a>00941 <span class="comment">                                    checksum. */</span>
<a name="l00942"></a>00942     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l00943"></a>00943     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#7675e6b9adbddbd545d3aac8ca092fbb">chkerr</a>);
<a name="l00944"></a>00944     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ip: bad checksum."</span>);
<a name="l00945"></a>00945     <span class="keywordflow">goto</span> drop;
<a name="l00946"></a>00946   }
<a name="l00947"></a>00947 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l00948"></a>00948 
<a name="l00949"></a>00949   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;proto == <a class="code" href="a00150.html#g517c770991459cc62dc009c0d3875c6a">UIP_PROTO_TCP</a>) { <span class="comment">/* Check for TCP packet. If so,</span>
<a name="l00950"></a>00950 <span class="comment">                                       proceed with TCP input</span>
<a name="l00951"></a>00951 <span class="comment">                                       processing. */</span>
<a name="l00952"></a>00952     <span class="keywordflow">goto</span> tcp_input;
<a name="l00953"></a>00953   }
<a name="l00954"></a>00954 
<a name="l00955"></a>00955 <span class="preprocessor">#if UIP_UDP</span>
<a name="l00956"></a>00956 <span class="preprocessor"></span>  <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;proto == <a class="code" href="a00150.html#gf72d7b9a737707dcfb2c41fec2b6792e">UIP_PROTO_UDP</a>) {
<a name="l00957"></a>00957     <span class="keywordflow">goto</span> udp_input;
<a name="l00958"></a>00958   }
<a name="l00959"></a>00959 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP */</span>
<a name="l00960"></a>00960 
<a name="l00961"></a>00961 <span class="preprocessor">#if !UIP_CONF_IPV6</span>
<a name="l00962"></a>00962 <span class="preprocessor"></span>  <span class="comment">/* ICMPv4 processing code follows. */</span>
<a name="l00963"></a>00963   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;proto != <a class="code" href="a00150.html#g359951eecd80541c2101f628a9da9146">UIP_PROTO_ICMP</a>) { <span class="comment">/* We only allow ICMP packets from</span>
<a name="l00964"></a>00964 <span class="comment">                                        here. */</span>
<a name="l00965"></a>00965     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l00966"></a>00966     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#b4622e2599ff3a592db09219b2641682">protoerr</a>);
<a name="l00967"></a>00967     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ip: neither tcp nor icmp."</span>);
<a name="l00968"></a>00968     <span class="keywordflow">goto</span> drop;
<a name="l00969"></a>00969   }
<a name="l00970"></a>00970 
<a name="l00971"></a>00971 <span class="preprocessor">#if UIP_PINGADDRCONF</span>
<a name="l00972"></a>00972 <span class="preprocessor"></span> icmp_input:
<a name="l00973"></a>00973 <span class="preprocessor">#endif </span><span class="comment">/* UIP_PINGADDRCONF */</span>
<a name="l00974"></a>00974   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#3983b45977630418d3038231aa8b68ed">icmp</a>.<a class="code" href="a00093.html#7f7bb2145afba5df00c6e10ddefa8ae1">recv</a>);
<a name="l00975"></a>00975 
<a name="l00976"></a>00976   <span class="comment">/* ICMP echo (i.e., ping) processing. This is simple, we only change</span>
<a name="l00977"></a>00977 <span class="comment">     the ICMP type from ECHO to ECHO_REPLY and adjust the ICMP</span>
<a name="l00978"></a>00978 <span class="comment">     checksum before we return the packet. */</span>
<a name="l00979"></a>00979   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;type != <a class="code" href="a00150.html#gd58231410d58e34b455328b888a9e73c">ICMP_ECHO</a>) {
<a name="l00980"></a>00980     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#3983b45977630418d3038231aa8b68ed">icmp</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l00981"></a>00981     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#3983b45977630418d3038231aa8b68ed">icmp</a>.<a class="code" href="a00093.html#8da121d6e50992ec55778f9b2141552d">typeerr</a>);
<a name="l00982"></a>00982     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"icmp: not icmp echo."</span>);
<a name="l00983"></a>00983     <span class="keywordflow">goto</span> drop;
<a name="l00984"></a>00984   }
<a name="l00985"></a>00985 
<a name="l00986"></a>00986   <span class="comment">/* If we are configured to use ping IP address assignment, we use</span>
<a name="l00987"></a>00987 <span class="comment">     the destination IP address of this ping packet and assign it to</span>
<a name="l00988"></a>00988 <span class="comment">     ourself. */</span>
<a name="l00989"></a>00989 <span class="preprocessor">#if UIP_PINGADDRCONF</span>
<a name="l00990"></a>00990 <span class="preprocessor"></span>  <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>[0] | <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>[1]) == 0) {
<a name="l00991"></a>00991     <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr[0];
<a name="l00992"></a>00992     <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>[1] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr[1];
<a name="l00993"></a>00993   }
<a name="l00994"></a>00994 <span class="preprocessor">#endif </span><span class="comment">/* UIP_PINGADDRCONF */</span>
<a name="l00995"></a>00995 
<a name="l00996"></a>00996   <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;type = <a class="code" href="a00150.html#g5c5b1834e497f53ad0ef947bbe9777fa">ICMP_ECHO_REPLY</a>;
<a name="l00997"></a>00997 
<a name="l00998"></a>00998   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;icmpchksum &gt;= <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(0xffff - (<a class="code" href="a00150.html#gd58231410d58e34b455328b888a9e73c">ICMP_ECHO</a> &lt;&lt; 8))) {
<a name="l00999"></a>00999     <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;icmpchksum += <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(<a class="code" href="a00150.html#gd58231410d58e34b455328b888a9e73c">ICMP_ECHO</a> &lt;&lt; 8) + 1;
<a name="l01000"></a>01000   } <span class="keywordflow">else</span> {
<a name="l01001"></a>01001     <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;icmpchksum += <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(<a class="code" href="a00150.html#gd58231410d58e34b455328b888a9e73c">ICMP_ECHO</a> &lt;&lt; 8);
<a name="l01002"></a>01002   }
<a name="l01003"></a>01003 
<a name="l01004"></a>01004   <span class="comment">/* Swap IP addresses. */</span>
<a name="l01005"></a>01005   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr, <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr);
<a name="l01006"></a>01006   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>);
<a name="l01007"></a>01007 
<a name="l01008"></a>01008   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#3983b45977630418d3038231aa8b68ed">icmp</a>.<a class="code" href="a00093.html#dc69abadd5aa07c7d74f9292db2cd93c">sent</a>);
<a name="l01009"></a>01009   <span class="keywordflow">goto</span> send;
<a name="l01010"></a>01010 
<a name="l01011"></a>01011   <span class="comment">/* End of IPv4 input header processing code. */</span>
<a name="l01012"></a>01012 <span class="preprocessor">#else </span><span class="comment">/* !UIP_CONF_IPV6 */</span>
<a name="l01013"></a>01013 
<a name="l01014"></a>01014   <span class="comment">/* This is IPv6 ICMPv6 processing code. */</span>
<a name="l01015"></a>01015   <a class="code" href="a00135.html#534d9e416324fb8ecca6b9cb4b1f6a6a">DEBUG_PRINTF</a>(<span class="stringliteral">"icmp6_input: length %d\n"</span>, <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>);
<a name="l01016"></a>01016 
<a name="l01017"></a>01017   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;proto != <a class="code" href="a00150.html#gad0321f4c570f9983c6de81ece3ddc20">UIP_PROTO_ICMP6</a>) { <span class="comment">/* We only allow ICMPv6 packets from</span>
<a name="l01018"></a>01018 <span class="comment">                                         here. */</span>
<a name="l01019"></a>01019     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l01020"></a>01020     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#b4622e2599ff3a592db09219b2641682">protoerr</a>);
<a name="l01021"></a>01021     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"ip: neither tcp nor icmp6."</span>);
<a name="l01022"></a>01022     <span class="keywordflow">goto</span> drop;
<a name="l01023"></a>01023   }
<a name="l01024"></a>01024 
<a name="l01025"></a>01025   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#3983b45977630418d3038231aa8b68ed">icmp</a>.<a class="code" href="a00093.html#7f7bb2145afba5df00c6e10ddefa8ae1">recv</a>);
<a name="l01026"></a>01026 
<a name="l01027"></a>01027   <span class="comment">/* If we get a neighbor solicitation for our address we should send</span>
<a name="l01028"></a>01028 <span class="comment">     a neighbor advertisement message back. */</span>
<a name="l01029"></a>01029   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;type == <a class="code" href="a00150.html#g1cea57e3ea526f210b1068e6dcf7b4f4">ICMP6_NEIGHBOR_SOLICITATION</a>) {
<a name="l01030"></a>01030     <span class="keywordflow">if</span>(<a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;icmp6data, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>)) {
<a name="l01031"></a>01031 
<a name="l01032"></a>01032       <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;options[0] == <a class="code" href="a00150.html#g42288d5c3cf4b10becefec657f441e54">ICMP6_OPTION_SOURCE_LINK_ADDRESS</a>) {
<a name="l01033"></a>01033         <span class="comment">/* Save the sender's address in our neighbor list. */</span>
<a name="l01034"></a>01034         <a class="code" href="a00132.html#88460bea09a462d0e22511cb567eee14">uip_neighbor_add</a>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;srcipaddr, &amp;(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;options[2]));
<a name="l01035"></a>01035       }
<a name="l01036"></a>01036       
<a name="l01037"></a>01037       <span class="comment">/* We should now send a neighbor advertisement back to where the</span>
<a name="l01038"></a>01038 <span class="comment">         neighbor solicication came from. */</span>
<a name="l01039"></a>01039       <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;type = <a class="code" href="a00150.html#g62c03e0a308cc23929a80fe8d8f9dc1e">ICMP6_NEIGHBOR_ADVERTISEMENT</a>;
<a name="l01040"></a>01040       <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;flags = <a class="code" href="a00150.html#g1d3211dbbdfb22d6a47b60dddcf945e8">ICMP6_FLAG_S</a>; <span class="comment">/* Solicited flag. */</span>
<a name="l01041"></a>01041       
<a name="l01042"></a>01042       <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;reserved1 = <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;reserved2 = <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;reserved3 = 0;
<a name="l01043"></a>01043       
<a name="l01044"></a>01044       <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;destipaddr, <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;srcipaddr);
<a name="l01045"></a>01045       <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;srcipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>);
<a name="l01046"></a>01046       <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;options[0] = <a class="code" href="a00150.html#g8387881de3a8bfd3c0d57b9d04ac9b7e">ICMP6_OPTION_TARGET_LINK_ADDRESS</a>;
<a name="l01047"></a>01047       <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;options[1] = 1;  <span class="comment">/* Options length, 1 = 8 bytes. */</span>
<a name="l01048"></a>01048       memcpy(&amp;(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;options[2]), &amp;<a class="code" href="a00150.html#g499bb98a0b4ae9a98553ede81317606d">uip_ethaddr</a>, <span class="keyword">sizeof</span>(<a class="code" href="a00150.html#g499bb98a0b4ae9a98553ede81317606d">uip_ethaddr</a>));
<a name="l01049"></a>01049       <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;icmpchksum = 0;
<a name="l01050"></a>01050       <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;icmpchksum = ~uip_icmp6chksum();
<a name="l01051"></a>01051       <span class="keywordflow">goto</span> send;
<a name="l01052"></a>01052       
<a name="l01053"></a>01053     }
<a name="l01054"></a>01054     <span class="keywordflow">goto</span> drop;
<a name="l01055"></a>01055   } <span class="keywordflow">else</span> <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;type == <a class="code" href="a00150.html#g4cc3e223b63f27b546d62e9a258dba5a">ICMP6_ECHO</a>) {
<a name="l01056"></a>01056     <span class="comment">/* ICMP echo (i.e., ping) processing. This is simple, we only</span>
<a name="l01057"></a>01057 <span class="comment">       change the ICMP type from ECHO to ECHO_REPLY and update the</span>
<a name="l01058"></a>01058 <span class="comment">       ICMP checksum before we return the packet. */</span>
<a name="l01059"></a>01059 
<a name="l01060"></a>01060     <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;type = <a class="code" href="a00150.html#g207d17b633cd095120a74bc1f2257b17">ICMP6_ECHO_REPLY</a>;
<a name="l01061"></a>01061     
<a name="l01062"></a>01062     <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr, <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr);
<a name="l01063"></a>01063     <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>);
<a name="l01064"></a>01064     <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;icmpchksum = 0;
<a name="l01065"></a>01065     <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;icmpchksum = ~uip_icmp6chksum();
<a name="l01066"></a>01066     
<a name="l01067"></a>01067     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#3983b45977630418d3038231aa8b68ed">icmp</a>.<a class="code" href="a00093.html#dc69abadd5aa07c7d74f9292db2cd93c">sent</a>);
<a name="l01068"></a>01068     <span class="keywordflow">goto</span> send;
<a name="l01069"></a>01069   } <span class="keywordflow">else</span> {
<a name="l01070"></a>01070     <a class="code" href="a00135.html#534d9e416324fb8ecca6b9cb4b1f6a6a">DEBUG_PRINTF</a>(<span class="stringliteral">"Unknown icmp6 message type %d\n"</span>, <a class="code" href="a00150.html#g4309376690872fa4beb4f025f5cc199b">ICMPBUF</a>-&gt;type);
<a name="l01071"></a>01071     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#3983b45977630418d3038231aa8b68ed">icmp</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l01072"></a>01072     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#3983b45977630418d3038231aa8b68ed">icmp</a>.<a class="code" href="a00093.html#8da121d6e50992ec55778f9b2141552d">typeerr</a>);
<a name="l01073"></a>01073     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"icmp: unknown ICMP message."</span>);
<a name="l01074"></a>01074     <span class="keywordflow">goto</span> drop;
<a name="l01075"></a>01075   }
<a name="l01076"></a>01076 
<a name="l01077"></a>01077   <span class="comment">/* End of IPv6 ICMP processing. */</span>
<a name="l01078"></a>01078   
<a name="l01079"></a>01079 <span class="preprocessor">#endif </span><span class="comment">/* !UIP_CONF_IPV6 */</span>
<a name="l01080"></a>01080 
<a name="l01081"></a>01081 <span class="preprocessor">#if UIP_UDP</span>
<a name="l01082"></a>01082 <span class="preprocessor"></span>  <span class="comment">/* UDP input processing. */</span>
<a name="l01083"></a>01083  udp_input:
<a name="l01084"></a>01084   <span class="comment">/* UDP processing is really just a hack. We don't do anything to the</span>
<a name="l01085"></a>01085 <span class="comment">     UDP/IP headers, but let the UDP application do all the hard</span>
<a name="l01086"></a>01086 <span class="comment">     work. If the application sets uip_slen, it has a packet to</span>
<a name="l01087"></a>01087 <span class="comment">     send. */</span>
<a name="l01088"></a>01088 <span class="preprocessor">#if UIP_UDP_CHECKSUMS</span>
<a name="l01089"></a>01089 <span class="preprocessor"></span>  <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> - <a class="code" href="a00150.html#g6f2b90c597ec23f39ec716ccec11233c">UIP_IPUDPH_LEN</a>;
<a name="l01090"></a>01090   <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a> = &amp;<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + UIP_IPUDPH_LEN];
<a name="l01091"></a>01091   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">UDPBUF</a>-&gt;udpchksum != 0 &amp;&amp; <a class="code" href="a00150.html#g7023a34ba9e9d03b5fbedbcb32924453">uip_udpchksum</a>() != 0xffff) {
<a name="l01092"></a>01092     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#4f39f0fe6a820d260fe6cddf9ccaa832">udp</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l01093"></a>01093     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#4f39f0fe6a820d260fe6cddf9ccaa832">udp</a>.<a class="code" href="a00093.html#7675e6b9adbddbd545d3aac8ca092fbb">chkerr</a>);
<a name="l01094"></a>01094     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"udp: bad checksum."</span>);
<a name="l01095"></a>01095     <span class="keywordflow">goto</span> drop;
<a name="l01096"></a>01096   }
<a name="l01097"></a>01097 <span class="preprocessor">#else </span><span class="comment">/* UIP_UDP_CHECKSUMS */</span>
<a name="l01098"></a>01098   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> - UIP_IPUDPH_LEN;
<a name="l01099"></a>01099 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP_CHECKSUMS */</span>
<a name="l01100"></a>01100 
<a name="l01101"></a>01101   <span class="comment">/* Demultiplex this UDP packet between the UDP "connections". */</span>
<a name="l01102"></a>01102   <span class="keywordflow">for</span>(<a class="code" href="a00095.html">uip_udp_conn</a> = &amp;<a class="code" href="a00150.html#geb533744817cf6695d75293369c2248b">uip_udp_conns</a>[0];
<a name="l01103"></a>01103       <a class="code" href="a00095.html">uip_udp_conn</a> &lt; &amp;<a class="code" href="a00150.html#geb533744817cf6695d75293369c2248b">uip_udp_conns</a>[<a class="code" href="a00153.html#g196379ceb1219a99f4495e41ccc9bbfb">UIP_UDP_CONNS</a>];
<a name="l01104"></a>01104       ++<a class="code" href="a00095.html">uip_udp_conn</a>) {
<a name="l01105"></a>01105     <span class="comment">/* If the local UDP port is non-zero, the connection is considered</span>
<a name="l01106"></a>01106 <span class="comment">       to be used. If so, the local port number is checked against the</span>
<a name="l01107"></a>01107 <span class="comment">       destination port number in the received packet. If the two port</span>
<a name="l01108"></a>01108 <span class="comment">       numbers match, the remote port number is checked if the</span>
<a name="l01109"></a>01109 <span class="comment">       connection is bound to a remote port. Finally, if the</span>
<a name="l01110"></a>01110 <span class="comment">       connection is bound to a remote IP address, the source IP</span>
<a name="l01111"></a>01111 <span class="comment">       address of the packet is checked. */</span>
<a name="l01112"></a>01112     <span class="keywordflow">if</span>(<a class="code" href="a00095.html">uip_udp_conn</a>-&gt;lport != 0 &amp;&amp;
<a name="l01113"></a>01113        <a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">UDPBUF</a>-&gt;destport == <a class="code" href="a00095.html">uip_udp_conn</a>-&gt;lport &amp;&amp;
<a name="l01114"></a>01114        (<a class="code" href="a00095.html">uip_udp_conn</a>-&gt;rport == 0 ||
<a name="l01115"></a>01115         <a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">UDPBUF</a>-&gt;srcport == <a class="code" href="a00095.html">uip_udp_conn</a>-&gt;rport) &amp;&amp;
<a name="l01116"></a>01116        (<a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00095.html">uip_udp_conn</a>-&gt;ripaddr, all_zeroes_addr) ||
<a name="l01117"></a>01117         <a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00095.html">uip_udp_conn</a>-&gt;ripaddr, all_ones_addr) ||
<a name="l01118"></a>01118         <a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr, <a class="code" href="a00095.html">uip_udp_conn</a>-&gt;ripaddr))) {
<a name="l01119"></a>01119       <span class="keywordflow">goto</span> udp_found;
<a name="l01120"></a>01120     }
<a name="l01121"></a>01121   }
<a name="l01122"></a>01122   <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"udp: no matching connection found"</span>);
<a name="l01123"></a>01123   <span class="keywordflow">goto</span> drop;
<a name="l01124"></a>01124   
<a name="l01125"></a>01125  udp_found:
<a name="l01126"></a>01126   <a class="code" href="a00088.html">uip_conn</a> = <a class="code" href="a00160.html#g070d2ce7b6bb7e5c05602aa8c308d0c4">NULL</a>;
<a name="l01127"></a>01127   <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#g39ce739bd352d7e348e37395ce903e43">UIP_NEWDATA</a>;
<a name="l01128"></a>01128   <a class="code" href="a00150.html#ga05a3dde2048480fa3ab2a5961898d18">uip_sappdata</a> = <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a> = &amp;<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + <a class="code" href="a00150.html#g6f2b90c597ec23f39ec716ccec11233c">UIP_IPUDPH_LEN</a>];
<a name="l01129"></a>01129   <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = 0;
<a name="l01130"></a>01130   <a class="code" href="a00160.html#g3d768e989e308144190ae1a5ddfa9726">UIP_UDP_APPCALL</a>();
<a name="l01131"></a>01131  udp_send:
<a name="l01132"></a>01132   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> == 0) {
<a name="l01133"></a>01133     <span class="keywordflow">goto</span> drop;
<a name="l01134"></a>01134   }
<a name="l01135"></a>01135   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> + <a class="code" href="a00150.html#g6f2b90c597ec23f39ec716ccec11233c">UIP_IPUDPH_LEN</a>;
<a name="l01136"></a>01136 
<a name="l01137"></a>01137 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l01138"></a>01138 <span class="preprocessor"></span>  <span class="comment">/* For IPv6, the IP length field does not include the IPv6 IP header</span>
<a name="l01139"></a>01139 <span class="comment">     length. */</span>
<a name="l01140"></a>01140   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] = ((<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> - <a class="code" href="a00150.html#g6bc12c6c7b56f73ce5d57abfdcdc6eb5">UIP_IPH_LEN</a>) &gt;&gt; 8);
<a name="l01141"></a>01141   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1] = ((<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> - <a class="code" href="a00150.html#g6bc12c6c7b56f73ce5d57abfdcdc6eb5">UIP_IPH_LEN</a>) &amp; 0xff);
<a name="l01142"></a>01142 <span class="preprocessor">#else </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l01143"></a>01143   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] = (<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt;&gt; 8);
<a name="l01144"></a>01144   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1] = (<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &amp; 0xff);
<a name="l01145"></a>01145 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l01146"></a>01146 
<a name="l01147"></a>01147   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ttl = <a class="code" href="a00095.html">uip_udp_conn</a>-&gt;ttl;
<a name="l01148"></a>01148   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;proto = <a class="code" href="a00150.html#gf72d7b9a737707dcfb2c41fec2b6792e">UIP_PROTO_UDP</a>;
<a name="l01149"></a>01149 
<a name="l01150"></a>01150   <a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">UDPBUF</a>-&gt;udplen = <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(<a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> + <a class="code" href="a00150.html#gb948296aea6b6b3aa1f156799c4d479c">UIP_UDPH_LEN</a>);
<a name="l01151"></a>01151   <a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">UDPBUF</a>-&gt;udpchksum = 0;
<a name="l01152"></a>01152 
<a name="l01153"></a>01153   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcport  = <a class="code" href="a00095.html">uip_udp_conn</a>-&gt;lport;
<a name="l01154"></a>01154   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destport = <a class="code" href="a00095.html">uip_udp_conn</a>-&gt;rport;
<a name="l01155"></a>01155 
<a name="l01156"></a>01156   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>);
<a name="l01157"></a>01157   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr, <a class="code" href="a00095.html">uip_udp_conn</a>-&gt;ripaddr);
<a name="l01158"></a>01158    
<a name="l01159"></a>01159   <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a> = &amp;<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + <a class="code" href="a00150.html#g15f2617f7dc1713f9d10282125c6027b">UIP_IPTCPH_LEN</a>];
<a name="l01160"></a>01160 
<a name="l01161"></a>01161 <span class="preprocessor">#if UIP_UDP_CHECKSUMS</span>
<a name="l01162"></a>01162 <span class="preprocessor"></span>  <span class="comment">/* Calculate UDP checksum. */</span>
<a name="l01163"></a>01163   <a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">UDPBUF</a>-&gt;udpchksum = ~(<a class="code" href="a00150.html#g7023a34ba9e9d03b5fbedbcb32924453">uip_udpchksum</a>());
<a name="l01164"></a>01164   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">UDPBUF</a>-&gt;udpchksum == 0) {
<a name="l01165"></a>01165     <a class="code" href="a00150.html#gb9435261753469accec0c9bf8a5a2686">UDPBUF</a>-&gt;udpchksum = 0xffff;
<a name="l01166"></a>01166   }
<a name="l01167"></a>01167 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP_CHECKSUMS */</span>
<a name="l01168"></a>01168   
<a name="l01169"></a>01169   <span class="keywordflow">goto</span> ip_send_nolen;
<a name="l01170"></a>01170 <span class="preprocessor">#endif </span><span class="comment">/* UIP_UDP */</span>
<a name="l01171"></a>01171   
<a name="l01172"></a>01172   <span class="comment">/* TCP input processing. */</span>
<a name="l01173"></a>01173  tcp_input:
<a name="l01174"></a>01174   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#e292b8977f6b81265bf14e1676face3e">tcp</a>.<a class="code" href="a00093.html#7f7bb2145afba5df00c6e10ddefa8ae1">recv</a>);
<a name="l01175"></a>01175 
<a name="l01176"></a>01176   <span class="comment">/* Start of TCP input header processing code. */</span>
<a name="l01177"></a>01177   
<a name="l01178"></a>01178   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g85b65e38aa74eba18979156f97a94a87">uip_tcpchksum</a>() != 0xffff) {   <span class="comment">/* Compute and check the TCP</span>
<a name="l01179"></a>01179 <span class="comment">                                       checksum. */</span>
<a name="l01180"></a>01180     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#e292b8977f6b81265bf14e1676face3e">tcp</a>.<a class="code" href="a00093.html#5d8996950cdf3d8130cc3ad340eb9dff">drop</a>);
<a name="l01181"></a>01181     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#e292b8977f6b81265bf14e1676face3e">tcp</a>.<a class="code" href="a00093.html#7675e6b9adbddbd545d3aac8ca092fbb">chkerr</a>);
<a name="l01182"></a>01182     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"tcp: bad checksum."</span>);
<a name="l01183"></a>01183     <span class="keywordflow">goto</span> drop;
<a name="l01184"></a>01184   }
<a name="l01185"></a>01185   
<a name="l01186"></a>01186   
<a name="l01187"></a>01187   <span class="comment">/* Demultiplex this segment. */</span>
<a name="l01188"></a>01188   <span class="comment">/* First check any active connections. */</span>
<a name="l01189"></a>01189   <span class="keywordflow">for</span>(uip_connr = &amp;<a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[0]; uip_connr &lt;= &amp;<a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[<a class="code" href="a00153.html#gf5fe83be78b78b9e7d9e7f1e34ab1cc5">UIP_CONNS</a> - 1];
<a name="l01190"></a>01190       ++uip_connr) {
<a name="l01191"></a>01191     <span class="keywordflow">if</span>(uip_connr-&gt;tcpstateflags != <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a> &amp;&amp;
<a name="l01192"></a>01192        <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destport == uip_connr-&gt;lport &amp;&amp;
<a name="l01193"></a>01193        <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcport == uip_connr-&gt;rport &amp;&amp;
<a name="l01194"></a>01194        <a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr, uip_connr-&gt;ripaddr)) {
<a name="l01195"></a>01195       <span class="keywordflow">goto</span> found;
<a name="l01196"></a>01196     }
<a name="l01197"></a>01197   }
<a name="l01198"></a>01198 
<a name="l01199"></a>01199   <span class="comment">/* If we didn't find and active connection that expected the packet,</span>
<a name="l01200"></a>01200 <span class="comment">     either this packet is an old duplicate, or this is a SYN packet</span>
<a name="l01201"></a>01201 <span class="comment">     destined for a connection in LISTEN. If the SYN flag isn't set,</span>
<a name="l01202"></a>01202 <span class="comment">     it is an old packet and we send a RST. */</span>
<a name="l01203"></a>01203   <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g1425d4a0c2760adb653a04c0fb137a8d">TCP_CTL</a>) != <a class="code" href="a00150.html#g6020613f5062417d9811cfa837215c83">TCP_SYN</a>) {
<a name="l01204"></a>01204     <span class="keywordflow">goto</span> reset;
<a name="l01205"></a>01205   }
<a name="l01206"></a>01206   
<a name="l01207"></a>01207   tmp16 = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destport;
<a name="l01208"></a>01208   <span class="comment">/* Next, check listening connections. */</span>
<a name="l01209"></a>01209   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#g8f4ebd8ef6c0ea665ed351d87fec09fd">UIP_LISTENPORTS</a>; ++c) {
<a name="l01210"></a>01210     <span class="keywordflow">if</span>(tmp16 == <a class="code" href="a00150.html#g236d5c7872f59c8fe7b701c7252b976e">uip_listenports</a>[c])
<a name="l01211"></a>01211       <span class="keywordflow">goto</span> found_listen;
<a name="l01212"></a>01212   }
<a name="l01213"></a>01213   
<a name="l01214"></a>01214   <span class="comment">/* No matching connection found, so we send a RST packet. */</span>
<a name="l01215"></a>01215   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#e292b8977f6b81265bf14e1676face3e">tcp</a>.<a class="code" href="a00093.html#e9205a565ea3c911a785fc4e87c91a58">synrst</a>);
<a name="l01216"></a>01216  reset:
<a name="l01217"></a>01217 
<a name="l01218"></a>01218   <span class="comment">/* We do not send resets in response to resets. */</span>
<a name="l01219"></a>01219   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g5ca559def464ef20d8b1f7d32f2f160d">TCP_RST</a>) {
<a name="l01220"></a>01220     <span class="keywordflow">goto</span> drop;
<a name="l01221"></a>01221   }
<a name="l01222"></a>01222 
<a name="l01223"></a>01223   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#e292b8977f6b81265bf14e1676face3e">tcp</a>.<a class="code" href="a00093.html#b6e9a75167bdddd561373bc5b6ef501c">rst</a>);
<a name="l01224"></a>01224   
<a name="l01225"></a>01225   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g5ca559def464ef20d8b1f7d32f2f160d">TCP_RST</a> | <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l01226"></a>01226   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00150.html#g15f2617f7dc1713f9d10282125c6027b">UIP_IPTCPH_LEN</a>;
<a name="l01227"></a>01227   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpoffset = 5 &lt;&lt; 4;
<a name="l01228"></a>01228 
<a name="l01229"></a>01229   <span class="comment">/* Flip the seqno and ackno fields in the TCP header. */</span>
<a name="l01230"></a>01230   c = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[3];
<a name="l01231"></a>01231   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[3] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[3];
<a name="l01232"></a>01232   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[3] = c;
<a name="l01233"></a>01233   
<a name="l01234"></a>01234   c = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[2];
<a name="l01235"></a>01235   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[2] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[2];
<a name="l01236"></a>01236   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[2] = c;
<a name="l01237"></a>01237   
<a name="l01238"></a>01238   c = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[1];
<a name="l01239"></a>01239   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[1] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[1];
<a name="l01240"></a>01240   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[1] = c;
<a name="l01241"></a>01241   
<a name="l01242"></a>01242   c = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[0];
<a name="l01243"></a>01243   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[0];
<a name="l01244"></a>01244   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[0] = c;
<a name="l01245"></a>01245 
<a name="l01246"></a>01246   <span class="comment">/* We also have to increase the sequence number we are</span>
<a name="l01247"></a>01247 <span class="comment">     acknowledging. If the least significant byte overflowed, we need</span>
<a name="l01248"></a>01248 <span class="comment">     to propagate the carry to the other bytes as well. */</span>
<a name="l01249"></a>01249   <span class="keywordflow">if</span>(++<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[3] == 0) {
<a name="l01250"></a>01250     <span class="keywordflow">if</span>(++<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[2] == 0) {
<a name="l01251"></a>01251       <span class="keywordflow">if</span>(++<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[1] == 0) {
<a name="l01252"></a>01252         ++<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[0];
<a name="l01253"></a>01253       }
<a name="l01254"></a>01254     }
<a name="l01255"></a>01255   }
<a name="l01256"></a>01256  
<a name="l01257"></a>01257   <span class="comment">/* Swap port numbers. */</span>
<a name="l01258"></a>01258   tmp16 = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcport;
<a name="l01259"></a>01259   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcport = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destport;
<a name="l01260"></a>01260   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destport = tmp16;
<a name="l01261"></a>01261   
<a name="l01262"></a>01262   <span class="comment">/* Swap IP addresses. */</span>
<a name="l01263"></a>01263   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr, <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr);
<a name="l01264"></a>01264   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>);
<a name="l01265"></a>01265   
<a name="l01266"></a>01266   <span class="comment">/* And send out the RST packet! */</span>
<a name="l01267"></a>01267   <span class="keywordflow">goto</span> tcp_send_noconn;
<a name="l01268"></a>01268 
<a name="l01269"></a>01269   <span class="comment">/* This label will be jumped to if we matched the incoming packet</span>
<a name="l01270"></a>01270 <span class="comment">     with a connection in LISTEN. In that case, we should create a new</span>
<a name="l01271"></a>01271 <span class="comment">     connection and send a SYNACK in return. */</span>
<a name="l01272"></a>01272  found_listen:
<a name="l01273"></a>01273   <span class="comment">/* First we check if there are any connections avaliable. Unused</span>
<a name="l01274"></a>01274 <span class="comment">     connections are kept in the same table as used connections, but</span>
<a name="l01275"></a>01275 <span class="comment">     unused ones have the tcpstate set to CLOSED. Also, connections in</span>
<a name="l01276"></a>01276 <span class="comment">     TIME_WAIT are kept track of and we'll use the oldest one if no</span>
<a name="l01277"></a>01277 <span class="comment">     CLOSED connections are found. Thanks to Eddie C. Dost for a very</span>
<a name="l01278"></a>01278 <span class="comment">     nice algorithm for the TIME_WAIT search. */</span>
<a name="l01279"></a>01279   uip_connr = 0;
<a name="l01280"></a>01280   <span class="keywordflow">for</span>(c = 0; c &lt; <a class="code" href="a00153.html#gf5fe83be78b78b9e7d9e7f1e34ab1cc5">UIP_CONNS</a>; ++c) {
<a name="l01281"></a>01281     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[c].<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> == <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>) {
<a name="l01282"></a>01282       uip_connr = &amp;<a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[c];
<a name="l01283"></a>01283       <span class="keywordflow">break</span>;
<a name="l01284"></a>01284     }
<a name="l01285"></a>01285     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[c].<a class="code" href="a00088.html#a5f58074435cdc180f17de69651beebd">tcpstateflags</a> == <a class="code" href="a00150.html#gfff0ed43201bf1e2020de1a0d6cac070">UIP_TIME_WAIT</a>) {
<a name="l01286"></a>01286       <span class="keywordflow">if</span>(uip_connr == 0 ||
<a name="l01287"></a>01287          <a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[c].<a class="code" href="a00087.html">timer</a> &gt; uip_connr-&gt;<a class="code" href="a00088.html#2d9732cf5752d30bd11cb25dc7d0c8d3">timer</a>) {
<a name="l01288"></a>01288         uip_connr = &amp;<a class="code" href="a00150.html#gf703683056d2bfa5c81fa157dcb20fe2">uip_conns</a>[c];
<a name="l01289"></a>01289       }
<a name="l01290"></a>01290     }
<a name="l01291"></a>01291   }
<a name="l01292"></a>01292 
<a name="l01293"></a>01293   <span class="keywordflow">if</span>(uip_connr == 0) {
<a name="l01294"></a>01294     <span class="comment">/* All connections are used already, we drop packet and hope that</span>
<a name="l01295"></a>01295 <span class="comment">       the remote end will retransmit the packet at a time when we</span>
<a name="l01296"></a>01296 <span class="comment">       have more spare connections. */</span>
<a name="l01297"></a>01297     <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#e292b8977f6b81265bf14e1676face3e">tcp</a>.<a class="code" href="a00093.html#494ea6767a8a8fab7abe96b799d6c3b3">syndrop</a>);
<a name="l01298"></a>01298     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"tcp: found no unused connections."</span>);
<a name="l01299"></a>01299     <span class="keywordflow">goto</span> drop;
<a name="l01300"></a>01300   }
<a name="l01301"></a>01301   <a class="code" href="a00088.html">uip_conn</a> = uip_connr;
<a name="l01302"></a>01302   
<a name="l01303"></a>01303   <span class="comment">/* Fill in the necessary fields for the new connection. */</span>
<a name="l01304"></a>01304   uip_connr-&gt;rto = uip_connr-&gt;timer = <a class="code" href="a00153.html#g15de27b044603284f68db05a378235a7">UIP_RTO</a>;
<a name="l01305"></a>01305   uip_connr-&gt;sa = 0;
<a name="l01306"></a>01306   uip_connr-&gt;sv = 4;
<a name="l01307"></a>01307   uip_connr-&gt;nrtx = 0;
<a name="l01308"></a>01308   uip_connr-&gt;lport = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destport;
<a name="l01309"></a>01309   uip_connr-&gt;rport = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcport;
<a name="l01310"></a>01310   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(uip_connr-&gt;ripaddr, <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr);
<a name="l01311"></a>01311   uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#ga5e3c856b86725125d19fccc34cd9eb5">UIP_SYN_RCVD</a>;
<a name="l01312"></a>01312 
<a name="l01313"></a>01313   uip_connr-&gt;snd_nxt[0] = iss[0];
<a name="l01314"></a>01314   uip_connr-&gt;snd_nxt[1] = iss[1];
<a name="l01315"></a>01315   uip_connr-&gt;snd_nxt[2] = iss[2];
<a name="l01316"></a>01316   uip_connr-&gt;snd_nxt[3] = iss[3];
<a name="l01317"></a>01317   uip_connr-&gt;len = 1;
<a name="l01318"></a>01318 
<a name="l01319"></a>01319   <span class="comment">/* rcv_nxt should be the seqno from the incoming packet + 1. */</span>
<a name="l01320"></a>01320   uip_connr-&gt;rcv_nxt[3] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[3];
<a name="l01321"></a>01321   uip_connr-&gt;rcv_nxt[2] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[2];
<a name="l01322"></a>01322   uip_connr-&gt;rcv_nxt[1] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[1];
<a name="l01323"></a>01323   uip_connr-&gt;rcv_nxt[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[0];
<a name="l01324"></a>01324   uip_add_rcv_nxt(1);
<a name="l01325"></a>01325 
<a name="l01326"></a>01326   <span class="comment">/* Parse the TCP MSS option, if present. */</span>
<a name="l01327"></a>01327   <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpoffset &amp; 0xf0) &gt; 0x50) {
<a name="l01328"></a>01328     <span class="keywordflow">for</span>(c = 0; c &lt; ((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpoffset &gt;&gt; 4) - 5) &lt;&lt; 2 ;) {
<a name="l01329"></a>01329       opt = <a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + c];
<a name="l01330"></a>01330       <span class="keywordflow">if</span>(opt == <a class="code" href="a00150.html#g1215163245304bad20d6c5608ad75ab7">TCP_OPT_END</a>) {
<a name="l01331"></a>01331         <span class="comment">/* End of options. */</span>
<a name="l01332"></a>01332         <span class="keywordflow">break</span>;
<a name="l01333"></a>01333       } <span class="keywordflow">else</span> <span class="keywordflow">if</span>(opt == <a class="code" href="a00150.html#g9f1822e1d231235edacad691f3cb7bbb">TCP_OPT_NOOP</a>) {
<a name="l01334"></a>01334         ++c;
<a name="l01335"></a>01335         <span class="comment">/* NOP option. */</span>
<a name="l01336"></a>01336       } <span class="keywordflow">else</span> <span class="keywordflow">if</span>(opt == <a class="code" href="a00150.html#g691688604655ea8943d15f14c60027d8">TCP_OPT_MSS</a> &amp;&amp;
<a name="l01337"></a>01337                 <a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 1 + c] == <a class="code" href="a00150.html#g12f3bf821224b8e7b48a57ed3cea15cf">TCP_OPT_MSS_LEN</a>) {
<a name="l01338"></a>01338         <span class="comment">/* An MSS option with the right option length. */</span>
<a name="l01339"></a>01339         tmp16 = ((<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>)<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 2 + c] &lt;&lt; 8) |
<a name="l01340"></a>01340           (<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>)<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#g15f2617f7dc1713f9d10282125c6027b">UIP_IPTCPH_LEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 3 + c];
<a name="l01341"></a>01341         uip_connr-&gt;initialmss = uip_connr-&gt;mss =
<a name="l01342"></a>01342           tmp16 &gt; <a class="code" href="a00153.html#g4910467b83a639f06739c82cd362037e">UIP_TCP_MSS</a>? <a class="code" href="a00153.html#g4910467b83a639f06739c82cd362037e">UIP_TCP_MSS</a>: tmp16;
<a name="l01343"></a>01343         
<a name="l01344"></a>01344         <span class="comment">/* And we are done processing options. */</span>
<a name="l01345"></a>01345         <span class="keywordflow">break</span>;
<a name="l01346"></a>01346       } <span class="keywordflow">else</span> {
<a name="l01347"></a>01347         <span class="comment">/* All other options have a length field, so that we easily</span>
<a name="l01348"></a>01348 <span class="comment">           can skip past them. */</span>
<a name="l01349"></a>01349         <span class="keywordflow">if</span>(<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 1 + c] == 0) {
<a name="l01350"></a>01350           <span class="comment">/* If the length field is zero, the options are malformed</span>
<a name="l01351"></a>01351 <span class="comment">             and we don't process them further. */</span>
<a name="l01352"></a>01352           <span class="keywordflow">break</span>;
<a name="l01353"></a>01353         }
<a name="l01354"></a>01354         c += <a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 1 + c];
<a name="l01355"></a>01355       }
<a name="l01356"></a>01356     }
<a name="l01357"></a>01357   }
<a name="l01358"></a>01358   
<a name="l01359"></a>01359   <span class="comment">/* Our response will be a SYNACK. */</span>
<a name="l01360"></a>01360 <span class="preprocessor">#if UIP_ACTIVE_OPEN</span>
<a name="l01361"></a>01361 <span class="preprocessor"></span> tcp_send_synack:
<a name="l01362"></a>01362   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l01363"></a>01363   
<a name="l01364"></a>01364  tcp_send_syn:
<a name="l01365"></a>01365   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags |= <a class="code" href="a00150.html#g6020613f5062417d9811cfa837215c83">TCP_SYN</a>;
<a name="l01366"></a>01366 <span class="preprocessor">#else </span><span class="comment">/* UIP_ACTIVE_OPEN */</span>
<a name="l01367"></a>01367  tcp_send_synack:
<a name="l01368"></a>01368   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g6020613f5062417d9811cfa837215c83">TCP_SYN</a> | <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l01369"></a>01369 <span class="preprocessor">#endif </span><span class="comment">/* UIP_ACTIVE_OPEN */</span>
<a name="l01370"></a>01370   
<a name="l01371"></a>01371   <span class="comment">/* We send out the TCP Maximum Segment Size option with our</span>
<a name="l01372"></a>01372 <span class="comment">     SYNACK. */</span>
<a name="l01373"></a>01373   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;optdata[0] = <a class="code" href="a00150.html#g691688604655ea8943d15f14c60027d8">TCP_OPT_MSS</a>;
<a name="l01374"></a>01374   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;optdata[1] = <a class="code" href="a00150.html#g12f3bf821224b8e7b48a57ed3cea15cf">TCP_OPT_MSS_LEN</a>;
<a name="l01375"></a>01375   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;optdata[2] = (<a class="code" href="a00153.html#g4910467b83a639f06739c82cd362037e">UIP_TCP_MSS</a>) / 256;
<a name="l01376"></a>01376   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;optdata[3] = (<a class="code" href="a00153.html#g4910467b83a639f06739c82cd362037e">UIP_TCP_MSS</a>) &amp; 255;
<a name="l01377"></a>01377   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00150.html#g15f2617f7dc1713f9d10282125c6027b">UIP_IPTCPH_LEN</a> + <a class="code" href="a00150.html#g12f3bf821224b8e7b48a57ed3cea15cf">TCP_OPT_MSS_LEN</a>;
<a name="l01378"></a>01378   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpoffset = ((<a class="code" href="a00150.html#g17d111686f98e4c09db73a770ac3f1a4">UIP_TCPH_LEN</a> + TCP_OPT_MSS_LEN) / 4) &lt;&lt; 4;
<a name="l01379"></a>01379   <span class="keywordflow">goto</span> tcp_send;
<a name="l01380"></a>01380 
<a name="l01381"></a>01381   <span class="comment">/* This label will be jumped to if we found an active connection. */</span>
<a name="l01382"></a>01382  found:
<a name="l01383"></a>01383   <a class="code" href="a00088.html">uip_conn</a> = uip_connr;
<a name="l01384"></a>01384   <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = 0;
<a name="l01385"></a>01385   <span class="comment">/* We do a very naive form of TCP reset processing; we just accept</span>
<a name="l01386"></a>01386 <span class="comment">     any RST and kill our connection. We should in fact check if the</span>
<a name="l01387"></a>01387 <span class="comment">     sequence number of this reset is wihtin our advertised window</span>
<a name="l01388"></a>01388 <span class="comment">     before we accept the reset. */</span>
<a name="l01389"></a>01389   <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g5ca559def464ef20d8b1f7d32f2f160d">TCP_RST</a>) {
<a name="l01390"></a>01390     uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>;
<a name="l01391"></a>01391     <a class="code" href="a00150.html#g013c3a06a8b58589a77f4a3442f89c2a">UIP_LOG</a>(<span class="stringliteral">"tcp: got reset, aborting connection."</span>);
<a name="l01392"></a>01392     <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#ga4c4310e54f18541b09e1e251fe7b22d">UIP_ABORT</a>;
<a name="l01393"></a>01393     <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01394"></a>01394     <span class="keywordflow">goto</span> drop;
<a name="l01395"></a>01395   }
<a name="l01396"></a>01396   <span class="comment">/* Calculated the length of the data, if the application has sent</span>
<a name="l01397"></a>01397 <span class="comment">     any data to us. */</span>
<a name="l01398"></a>01398   c = (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpoffset &gt;&gt; 4) &lt;&lt; 2;
<a name="l01399"></a>01399   <span class="comment">/* uip_len will contain the length of the actual TCP data. This is</span>
<a name="l01400"></a>01400 <span class="comment">     calculated by subtracing the length of the TCP header (in</span>
<a name="l01401"></a>01401 <span class="comment">     c) and the length of the IP header (20 bytes). */</span>
<a name="l01402"></a>01402   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> - c - <a class="code" href="a00150.html#g6bc12c6c7b56f73ce5d57abfdcdc6eb5">UIP_IPH_LEN</a>;
<a name="l01403"></a>01403 
<a name="l01404"></a>01404   <span class="comment">/* First, check if the sequence number of the incoming packet is</span>
<a name="l01405"></a>01405 <span class="comment">     what we're expecting next. If not, we send out an ACK with the</span>
<a name="l01406"></a>01406 <span class="comment">     correct numbers in. */</span>
<a name="l01407"></a>01407   <span class="keywordflow">if</span>(!(((uip_connr-&gt;tcpstateflags &amp; <a class="code" href="a00150.html#g13dfcb4a5f920e108253ade527a66cc2">UIP_TS_MASK</a>) == <a class="code" href="a00150.html#g8af482dec973db57d8b3bd3f69461488">UIP_SYN_SENT</a>) &amp;&amp;
<a name="l01408"></a>01408        ((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g1425d4a0c2760adb653a04c0fb137a8d">TCP_CTL</a>) == (<a class="code" href="a00150.html#g6020613f5062417d9811cfa837215c83">TCP_SYN</a> | <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>)))) {
<a name="l01409"></a>01409     <span class="keywordflow">if</span>((<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt; 0 || ((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; (<a class="code" href="a00150.html#g6020613f5062417d9811cfa837215c83">TCP_SYN</a> | <a class="code" href="a00150.html#g88e60aa2cf23e1c65d630701db08c743">TCP_FIN</a>)) != 0)) &amp;&amp;
<a name="l01410"></a>01410        (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[0] != uip_connr-&gt;rcv_nxt[0] ||
<a name="l01411"></a>01411         <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[1] != uip_connr-&gt;rcv_nxt[1] ||
<a name="l01412"></a>01412         <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[2] != uip_connr-&gt;rcv_nxt[2] ||
<a name="l01413"></a>01413         <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[3] != uip_connr-&gt;rcv_nxt[3])) {
<a name="l01414"></a>01414       <span class="keywordflow">goto</span> tcp_send_ack;
<a name="l01415"></a>01415     }
<a name="l01416"></a>01416   }
<a name="l01417"></a>01417 
<a name="l01418"></a>01418   <span class="comment">/* Next, check if the incoming segment acknowledges any outstanding</span>
<a name="l01419"></a>01419 <span class="comment">     data. If so, we update the sequence number, reset the length of</span>
<a name="l01420"></a>01420 <span class="comment">     the outstanding data, calculate RTT estimations, and reset the</span>
<a name="l01421"></a>01421 <span class="comment">     retransmission timer. */</span>
<a name="l01422"></a>01422   <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>) &amp;&amp; <a class="code" href="a00147.html#gef14e83c046e19ab9fe9d1bbcca276c2">uip_outstanding</a>(uip_connr)) {
<a name="l01423"></a>01423     <a class="code" href="a00150.html#g6832e4d2d046536b6472f7ac92340f68">uip_add32</a>(uip_connr-&gt;snd_nxt, uip_connr-&gt;len);
<a name="l01424"></a>01424 
<a name="l01425"></a>01425     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[0] == <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[0] &amp;&amp;
<a name="l01426"></a>01426        <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[1] == <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[1] &amp;&amp;
<a name="l01427"></a>01427        <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[2] == <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[2] &amp;&amp;
<a name="l01428"></a>01428        <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[3] == <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[3]) {
<a name="l01429"></a>01429       <span class="comment">/* Update sequence number. */</span>
<a name="l01430"></a>01430       uip_connr-&gt;snd_nxt[0] = <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[0];
<a name="l01431"></a>01431       uip_connr-&gt;snd_nxt[1] = <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[1];
<a name="l01432"></a>01432       uip_connr-&gt;snd_nxt[2] = <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[2];
<a name="l01433"></a>01433       uip_connr-&gt;snd_nxt[3] = <a class="code" href="a00151.html#g2a0cf5d86c58fab216414ce59bf1fea1">uip_acc32</a>[3];
<a name="l01434"></a>01434         
<a name="l01435"></a>01435 
<a name="l01436"></a>01436       <span class="comment">/* Do RTT estimation, unless we have done retransmissions. */</span>
<a name="l01437"></a>01437       <span class="keywordflow">if</span>(uip_connr-&gt;nrtx == 0) {
<a name="l01438"></a>01438         <span class="keywordtype">signed</span> <span class="keywordtype">char</span> m;
<a name="l01439"></a>01439         m = uip_connr-&gt;rto - uip_connr-&gt;timer;
<a name="l01440"></a>01440         <span class="comment">/* This is taken directly from VJs original code in his paper */</span>
<a name="l01441"></a>01441         m = m - (uip_connr-&gt;sa &gt;&gt; 3);
<a name="l01442"></a>01442         uip_connr-&gt;sa += m;
<a name="l01443"></a>01443         <span class="keywordflow">if</span>(m &lt; 0) {
<a name="l01444"></a>01444           m = -m;
<a name="l01445"></a>01445         }
<a name="l01446"></a>01446         m = m - (uip_connr-&gt;sv &gt;&gt; 2);
<a name="l01447"></a>01447         uip_connr-&gt;sv += m;
<a name="l01448"></a>01448         uip_connr-&gt;rto = (uip_connr-&gt;sa &gt;&gt; 3) + uip_connr-&gt;sv;
<a name="l01449"></a>01449 
<a name="l01450"></a>01450       }
<a name="l01451"></a>01451       <span class="comment">/* Set the acknowledged flag. */</span>
<a name="l01452"></a>01452       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#g6bfa488f87f68a6f7f4a3efb9e45eaf8">UIP_ACKDATA</a>;
<a name="l01453"></a>01453       <span class="comment">/* Reset the retransmission timer. */</span>
<a name="l01454"></a>01454       uip_connr-&gt;timer = uip_connr-&gt;rto;
<a name="l01455"></a>01455 
<a name="l01456"></a>01456       <span class="comment">/* Reset length of outstanding data. */</span>
<a name="l01457"></a>01457       uip_connr-&gt;len = 0;
<a name="l01458"></a>01458     }
<a name="l01459"></a>01459     
<a name="l01460"></a>01460   }
<a name="l01461"></a>01461 
<a name="l01462"></a>01462   <span class="comment">/* Do different things depending on in what state the connection is. */</span>
<a name="l01463"></a>01463   <span class="keywordflow">switch</span>(uip_connr-&gt;tcpstateflags &amp; <a class="code" href="a00150.html#g13dfcb4a5f920e108253ade527a66cc2">UIP_TS_MASK</a>) {
<a name="l01464"></a>01464     <span class="comment">/* CLOSED and LISTEN are not handled here. CLOSE_WAIT is not</span>
<a name="l01465"></a>01465 <span class="comment">        implemented, since we force the application to close when the</span>
<a name="l01466"></a>01466 <span class="comment">        peer sends a FIN (hence the application goes directly from</span>
<a name="l01467"></a>01467 <span class="comment">        ESTABLISHED to LAST_ACK). */</span>
<a name="l01468"></a>01468   <span class="keywordflow">case</span> <a class="code" href="a00150.html#ga5e3c856b86725125d19fccc34cd9eb5">UIP_SYN_RCVD</a>:
<a name="l01469"></a>01469     <span class="comment">/* In SYN_RCVD we have sent out a SYNACK in response to a SYN, and</span>
<a name="l01470"></a>01470 <span class="comment">       we are waiting for an ACK that acknowledges the data we sent</span>
<a name="l01471"></a>01471 <span class="comment">       out the last time. Therefore, we want to have the UIP_ACKDATA</span>
<a name="l01472"></a>01472 <span class="comment">       flag set. If so, we enter the ESTABLISHED state. */</span>
<a name="l01473"></a>01473     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; <a class="code" href="a00150.html#g6bfa488f87f68a6f7f4a3efb9e45eaf8">UIP_ACKDATA</a>) {
<a name="l01474"></a>01474       uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#gae59b70658f28ee6e998eaaab05e423f">UIP_ESTABLISHED</a>;
<a name="l01475"></a>01475       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#gf84316f469ce0726985c0702db49a989">UIP_CONNECTED</a>;
<a name="l01476"></a>01476       uip_connr-&gt;len = 0;
<a name="l01477"></a>01477       <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt; 0) {
<a name="l01478"></a>01478         <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> |= <a class="code" href="a00150.html#g39ce739bd352d7e348e37395ce903e43">UIP_NEWDATA</a>;
<a name="l01479"></a>01479         uip_add_rcv_nxt(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>);
<a name="l01480"></a>01480       }
<a name="l01481"></a>01481       <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = 0;
<a name="l01482"></a>01482       <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01483"></a>01483       <span class="keywordflow">goto</span> appsend;
<a name="l01484"></a>01484     }
<a name="l01485"></a>01485     <span class="keywordflow">goto</span> drop;
<a name="l01486"></a>01486 <span class="preprocessor">#if UIP_ACTIVE_OPEN</span>
<a name="l01487"></a>01487 <span class="preprocessor"></span>  <span class="keywordflow">case</span> <a class="code" href="a00150.html#g8af482dec973db57d8b3bd3f69461488">UIP_SYN_SENT</a>:
<a name="l01488"></a>01488     <span class="comment">/* In SYN_SENT, we wait for a SYNACK that is sent in response to</span>
<a name="l01489"></a>01489 <span class="comment">       our SYN. The rcv_nxt is set to sequence number in the SYNACK</span>
<a name="l01490"></a>01490 <span class="comment">       plus one, and we send an ACK. We move into the ESTABLISHED</span>
<a name="l01491"></a>01491 <span class="comment">       state. */</span>
<a name="l01492"></a>01492     <span class="keywordflow">if</span>((<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; UIP_ACKDATA) &amp;&amp;
<a name="l01493"></a>01493        (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g1425d4a0c2760adb653a04c0fb137a8d">TCP_CTL</a>) == (<a class="code" href="a00150.html#g6020613f5062417d9811cfa837215c83">TCP_SYN</a> | <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>)) {
<a name="l01494"></a>01494 
<a name="l01495"></a>01495       <span class="comment">/* Parse the TCP MSS option, if present. */</span>
<a name="l01496"></a>01496       <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpoffset &amp; 0xf0) &gt; 0x50) {
<a name="l01497"></a>01497         <span class="keywordflow">for</span>(c = 0; c &lt; ((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpoffset &gt;&gt; 4) - 5) &lt;&lt; 2 ;) {
<a name="l01498"></a>01498           opt = <a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#g15f2617f7dc1713f9d10282125c6027b">UIP_IPTCPH_LEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + c];
<a name="l01499"></a>01499           <span class="keywordflow">if</span>(opt == <a class="code" href="a00150.html#g1215163245304bad20d6c5608ad75ab7">TCP_OPT_END</a>) {
<a name="l01500"></a>01500             <span class="comment">/* End of options. */</span>
<a name="l01501"></a>01501             <span class="keywordflow">break</span>;
<a name="l01502"></a>01502           } <span class="keywordflow">else</span> <span class="keywordflow">if</span>(opt == <a class="code" href="a00150.html#g9f1822e1d231235edacad691f3cb7bbb">TCP_OPT_NOOP</a>) {
<a name="l01503"></a>01503             ++c;
<a name="l01504"></a>01504             <span class="comment">/* NOP option. */</span>
<a name="l01505"></a>01505           } <span class="keywordflow">else</span> <span class="keywordflow">if</span>(opt == <a class="code" href="a00150.html#g691688604655ea8943d15f14c60027d8">TCP_OPT_MSS</a> &amp;&amp;
<a name="l01506"></a>01506                     <a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 1 + c] == TCP_OPT_MSS_LEN) {
<a name="l01507"></a>01507             <span class="comment">/* An MSS option with the right option length. */</span>
<a name="l01508"></a>01508             tmp16 = (<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 2 + c] &lt;&lt; 8) |
<a name="l01509"></a>01509               <a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 3 + c];
<a name="l01510"></a>01510             uip_connr-&gt;initialmss =
<a name="l01511"></a>01511               uip_connr-&gt;mss = tmp16 &gt; <a class="code" href="a00153.html#g4910467b83a639f06739c82cd362037e">UIP_TCP_MSS</a>? <a class="code" href="a00153.html#g4910467b83a639f06739c82cd362037e">UIP_TCP_MSS</a>: tmp16;
<a name="l01512"></a>01512 
<a name="l01513"></a>01513             <span class="comment">/* And we are done processing options. */</span>
<a name="l01514"></a>01514             <span class="keywordflow">break</span>;
<a name="l01515"></a>01515           } <span class="keywordflow">else</span> {
<a name="l01516"></a>01516             <span class="comment">/* All other options have a length field, so that we easily</span>
<a name="l01517"></a>01517 <span class="comment">               can skip past them. */</span>
<a name="l01518"></a>01518             <span class="keywordflow">if</span>(<a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 1 + c] == 0) {
<a name="l01519"></a>01519               <span class="comment">/* If the length field is zero, the options are malformed</span>
<a name="l01520"></a>01520 <span class="comment">                 and we don't process them further. */</span>
<a name="l01521"></a>01521               <span class="keywordflow">break</span>;
<a name="l01522"></a>01522             }
<a name="l01523"></a>01523             c += <a class="code" href="a00146.html#gb81e78f890dbbee50c533a9734b74fd9">uip_buf</a>[<a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a> + <a class="code" href="a00153.html#ge6f4a2453dbd8bc60e6a82774552366a">UIP_LLH_LEN</a> + 1 + c];
<a name="l01524"></a>01524           }
<a name="l01525"></a>01525         }
<a name="l01526"></a>01526       }
<a name="l01527"></a>01527       uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#gae59b70658f28ee6e998eaaab05e423f">UIP_ESTABLISHED</a>;
<a name="l01528"></a>01528       uip_connr-&gt;rcv_nxt[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[0];
<a name="l01529"></a>01529       uip_connr-&gt;rcv_nxt[1] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[1];
<a name="l01530"></a>01530       uip_connr-&gt;rcv_nxt[2] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[2];
<a name="l01531"></a>01531       uip_connr-&gt;rcv_nxt[3] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[3];
<a name="l01532"></a>01532       uip_add_rcv_nxt(1);
<a name="l01533"></a>01533       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#gf84316f469ce0726985c0702db49a989">UIP_CONNECTED</a> | <a class="code" href="a00150.html#g39ce739bd352d7e348e37395ce903e43">UIP_NEWDATA</a>;
<a name="l01534"></a>01534       uip_connr-&gt;len = 0;
<a name="l01535"></a>01535       <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = 0;
<a name="l01536"></a>01536       <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = 0;
<a name="l01537"></a>01537       <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01538"></a>01538       <span class="keywordflow">goto</span> appsend;
<a name="l01539"></a>01539     }
<a name="l01540"></a>01540     <span class="comment">/* Inform the application that the connection failed */</span>
<a name="l01541"></a>01541     <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = <a class="code" href="a00150.html#ga4c4310e54f18541b09e1e251fe7b22d">UIP_ABORT</a>;
<a name="l01542"></a>01542     <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01543"></a>01543     <span class="comment">/* The connection is closed after we send the RST */</span>
<a name="l01544"></a>01544     <a class="code" href="a00088.html">uip_conn</a>-&gt;tcpstateflags = <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>;
<a name="l01545"></a>01545     <span class="keywordflow">goto</span> reset;
<a name="l01546"></a>01546 <span class="preprocessor">#endif </span><span class="comment">/* UIP_ACTIVE_OPEN */</span>
<a name="l01547"></a>01547     
<a name="l01548"></a>01548   <span class="keywordflow">case</span> <a class="code" href="a00150.html#gae59b70658f28ee6e998eaaab05e423f">UIP_ESTABLISHED</a>:
<a name="l01549"></a>01549     <span class="comment">/* In the ESTABLISHED state, we call upon the application to feed</span>
<a name="l01550"></a>01550 <span class="comment">    data into the uip_buf. If the UIP_ACKDATA flag is set, the</span>
<a name="l01551"></a>01551 <span class="comment">    application should put new data into the buffer, otherwise we are</span>
<a name="l01552"></a>01552 <span class="comment">    retransmitting an old segment, and the application should put that</span>
<a name="l01553"></a>01553 <span class="comment">    data into the buffer.</span>
<a name="l01554"></a>01554 <span class="comment"></span>
<a name="l01555"></a>01555 <span class="comment">    If the incoming packet is a FIN, we should close the connection on</span>
<a name="l01556"></a>01556 <span class="comment">    this side as well, and we send out a FIN and enter the LAST_ACK</span>
<a name="l01557"></a>01557 <span class="comment">    state. We require that there is no outstanding data; otherwise the</span>
<a name="l01558"></a>01558 <span class="comment">    sequence numbers will be screwed up. */</span>
<a name="l01559"></a>01559 
<a name="l01560"></a>01560     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g88e60aa2cf23e1c65d630701db08c743">TCP_FIN</a> &amp;&amp; !(uip_connr-&gt;tcpstateflags &amp; <a class="code" href="a00150.html#gde29ec025e6754afd8cc24c954a8dec8">UIP_STOPPED</a>)) {
<a name="l01561"></a>01561       <span class="keywordflow">if</span>(<a class="code" href="a00147.html#gef14e83c046e19ab9fe9d1bbcca276c2">uip_outstanding</a>(uip_connr)) {
<a name="l01562"></a>01562         <span class="keywordflow">goto</span> drop;
<a name="l01563"></a>01563       }
<a name="l01564"></a>01564       uip_add_rcv_nxt(1 + <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>);
<a name="l01565"></a>01565       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> |= <a class="code" href="a00150.html#g57e6dc1d58a36d0ed53a3dd29ccc5798">UIP_CLOSE</a>;
<a name="l01566"></a>01566       <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt; 0) {
<a name="l01567"></a>01567         <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> |= <a class="code" href="a00150.html#g39ce739bd352d7e348e37395ce903e43">UIP_NEWDATA</a>;
<a name="l01568"></a>01568       }
<a name="l01569"></a>01569       <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01570"></a>01570       uip_connr-&gt;len = 1;
<a name="l01571"></a>01571       uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#gd135fb0cfdfb2c212f0f51865a3640e4">UIP_LAST_ACK</a>;
<a name="l01572"></a>01572       uip_connr-&gt;nrtx = 0;
<a name="l01573"></a>01573     tcp_send_finack:
<a name="l01574"></a>01574       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g88e60aa2cf23e1c65d630701db08c743">TCP_FIN</a> | <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l01575"></a>01575       <span class="keywordflow">goto</span> tcp_send_nodata;
<a name="l01576"></a>01576     }
<a name="l01577"></a>01577 
<a name="l01578"></a>01578     <span class="comment">/* Check the URG flag. If this is set, the segment carries urgent</span>
<a name="l01579"></a>01579 <span class="comment">       data that we must pass to the application. */</span>
<a name="l01580"></a>01580     <span class="keywordflow">if</span>((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#gc84f499cba8a02fc0e306c10b2acabf0">TCP_URG</a>) != 0) {
<a name="l01581"></a>01581 <span class="preprocessor">#if UIP_URGDATA &gt; 0</span>
<a name="l01582"></a>01582 <span class="preprocessor"></span>      uip_urglen = (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;urgp[0] &lt;&lt; 8) | <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;urgp[1];
<a name="l01583"></a>01583       <span class="keywordflow">if</span>(uip_urglen &gt; <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>) {
<a name="l01584"></a>01584         <span class="comment">/* There is more urgent data in the next segment to come. */</span>
<a name="l01585"></a>01585         uip_urglen = <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>;
<a name="l01586"></a>01586       }
<a name="l01587"></a>01587       uip_add_rcv_nxt(uip_urglen);
<a name="l01588"></a>01588       <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> -= uip_urglen;
<a name="l01589"></a>01589       uip_urgdata = <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a>;
<a name="l01590"></a>01590       <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a> += uip_urglen;
<a name="l01591"></a>01591     } <span class="keywordflow">else</span> {
<a name="l01592"></a>01592       uip_urglen = 0;
<a name="l01593"></a>01593 <span class="preprocessor">#else </span><span class="comment">/* UIP_URGDATA &gt; 0 */</span>
<a name="l01594"></a>01594       <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a> = ((<span class="keywordtype">char</span> *)<a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a>) + ((<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;urgp[0] &lt;&lt; 8) | <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;urgp[1]);
<a name="l01595"></a>01595       <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> -= (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;urgp[0] &lt;&lt; 8) | <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;urgp[1];
<a name="l01596"></a>01596 #endif <span class="comment">/* UIP_URGDATA &gt; 0 */</span>
<a name="l01597"></a>01597     }
<a name="l01598"></a>01598 
<a name="l01599"></a>01599     <span class="comment">/* If uip_len &gt; 0 we have TCP data in the packet, and we flag this</span>
<a name="l01600"></a>01600 <span class="comment">       by setting the UIP_NEWDATA flag and update the sequence number</span>
<a name="l01601"></a>01601 <span class="comment">       we acknowledge. If the application has stopped the dataflow</span>
<a name="l01602"></a>01602 <span class="comment">       using uip_stop(), we must not accept any data packets from the</span>
<a name="l01603"></a>01603 <span class="comment">       remote host. */</span>
<a name="l01604"></a>01604     <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt; 0 &amp;&amp; !(uip_connr-&gt;tcpstateflags &amp; <a class="code" href="a00150.html#gde29ec025e6754afd8cc24c954a8dec8">UIP_STOPPED</a>)) {
<a name="l01605"></a>01605       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> |= <a class="code" href="a00150.html#g39ce739bd352d7e348e37395ce903e43">UIP_NEWDATA</a>;
<a name="l01606"></a>01606       uip_add_rcv_nxt(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>);
<a name="l01607"></a>01607     }
<a name="l01608"></a>01608 
<a name="l01609"></a>01609     <span class="comment">/* Check if the available buffer space advertised by the other end</span>
<a name="l01610"></a>01610 <span class="comment">       is smaller than the initial MSS for this connection. If so, we</span>
<a name="l01611"></a>01611 <span class="comment">       set the current MSS to the window size to ensure that the</span>
<a name="l01612"></a>01612 <span class="comment">       application does not send more data than the other end can</span>
<a name="l01613"></a>01613 <span class="comment">       handle.</span>
<a name="l01614"></a>01614 <span class="comment"></span>
<a name="l01615"></a>01615 <span class="comment">       If the remote host advertises a zero window, we set the MSS to</span>
<a name="l01616"></a>01616 <span class="comment">       the initial MSS so that the application will send an entire MSS</span>
<a name="l01617"></a>01617 <span class="comment">       of data. This data will not be acknowledged by the receiver,</span>
<a name="l01618"></a>01618 <span class="comment">       and the application will retransmit it. This is called the</span>
<a name="l01619"></a>01619 <span class="comment">       "persistent timer" and uses the retransmission mechanim.</span>
<a name="l01620"></a>01620 <span class="comment">    */</span>
<a name="l01621"></a>01621     tmp16 = ((<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>)<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;wnd[0] &lt;&lt; 8) + (<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>)<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;wnd[1];
<a name="l01622"></a>01622     <span class="keywordflow">if</span>(tmp16 &gt; uip_connr-&gt;initialmss ||
<a name="l01623"></a>01623        tmp16 == 0) {
<a name="l01624"></a>01624       tmp16 = uip_connr-&gt;initialmss;
<a name="l01625"></a>01625     }
<a name="l01626"></a>01626     uip_connr-&gt;mss = tmp16;
<a name="l01627"></a>01627 
<a name="l01628"></a>01628     <span class="comment">/* If this packet constitutes an ACK for outstanding data (flagged</span>
<a name="l01629"></a>01629 <span class="comment">       by the UIP_ACKDATA flag, we should call the application since it</span>
<a name="l01630"></a>01630 <span class="comment">       might want to send more data. If the incoming packet had data</span>
<a name="l01631"></a>01631 <span class="comment">       from the peer (as flagged by the UIP_NEWDATA flag), the</span>
<a name="l01632"></a>01632 <span class="comment">       application must also be notified.</span>
<a name="l01633"></a>01633 <span class="comment"></span>
<a name="l01634"></a>01634 <span class="comment">       When the application is called, the global variable uip_len</span>
<a name="l01635"></a>01635 <span class="comment">       contains the length of the incoming data. The application can</span>
<a name="l01636"></a>01636 <span class="comment">       access the incoming data through the global pointer</span>
<a name="l01637"></a>01637 <span class="comment">       uip_appdata, which usually points UIP_IPTCPH_LEN + UIP_LLH_LEN</span>
<a name="l01638"></a>01638 <span class="comment">       bytes into the uip_buf array.</span>
<a name="l01639"></a>01639 <span class="comment"></span>
<a name="l01640"></a>01640 <span class="comment">       If the application wishes to send any data, this data should be</span>
<a name="l01641"></a>01641 <span class="comment">       put into the uip_appdata and the length of the data should be</span>
<a name="l01642"></a>01642 <span class="comment">       put into uip_len. If the application don't have any data to</span>
<a name="l01643"></a>01643 <span class="comment">       send, uip_len must be set to 0. */</span>
<a name="l01644"></a>01644     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; (<a class="code" href="a00150.html#g39ce739bd352d7e348e37395ce903e43">UIP_NEWDATA</a> | UIP_ACKDATA)) {
<a name="l01645"></a>01645       <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = 0;
<a name="l01646"></a>01646       <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01647"></a>01647 
<a name="l01648"></a>01648     appsend:
<a name="l01649"></a>01649       
<a name="l01650"></a>01650       <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; <a class="code" href="a00150.html#ga4c4310e54f18541b09e1e251fe7b22d">UIP_ABORT</a>) {
<a name="l01651"></a>01651         <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = 0;
<a name="l01652"></a>01652         uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>;
<a name="l01653"></a>01653         <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g5ca559def464ef20d8b1f7d32f2f160d">TCP_RST</a> | <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l01654"></a>01654         <span class="keywordflow">goto</span> tcp_send_nodata;
<a name="l01655"></a>01655       }
<a name="l01656"></a>01656 
<a name="l01657"></a>01657       <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; <a class="code" href="a00150.html#g57e6dc1d58a36d0ed53a3dd29ccc5798">UIP_CLOSE</a>) {
<a name="l01658"></a>01658         <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = 0;
<a name="l01659"></a>01659         uip_connr-&gt;len = 1;
<a name="l01660"></a>01660         uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#ga533c394b1fa0030205534befa31c525">UIP_FIN_WAIT_1</a>;
<a name="l01661"></a>01661         uip_connr-&gt;nrtx = 0;
<a name="l01662"></a>01662         <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g88e60aa2cf23e1c65d630701db08c743">TCP_FIN</a> | <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l01663"></a>01663         <span class="keywordflow">goto</span> tcp_send_nodata;
<a name="l01664"></a>01664       }
<a name="l01665"></a>01665 
<a name="l01666"></a>01666       <span class="comment">/* If uip_slen &gt; 0, the application has data to be sent. */</span>
<a name="l01667"></a>01667       <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> &gt; 0) {
<a name="l01668"></a>01668 
<a name="l01669"></a>01669         <span class="comment">/* If the connection has acknowledged data, the contents of</span>
<a name="l01670"></a>01670 <span class="comment">           the -&gt;len variable should be discarded. */</span>
<a name="l01671"></a>01671         <span class="keywordflow">if</span>((<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; UIP_ACKDATA) != 0) {
<a name="l01672"></a>01672           uip_connr-&gt;len = 0;
<a name="l01673"></a>01673         }
<a name="l01674"></a>01674 
<a name="l01675"></a>01675         <span class="comment">/* If the -&gt;len variable is non-zero the connection has</span>
<a name="l01676"></a>01676 <span class="comment">           already data in transit and cannot send anymore right</span>
<a name="l01677"></a>01677 <span class="comment">           now. */</span>
<a name="l01678"></a>01678         <span class="keywordflow">if</span>(uip_connr-&gt;len == 0) {
<a name="l01679"></a>01679 
<a name="l01680"></a>01680           <span class="comment">/* The application cannot send more than what is allowed by</span>
<a name="l01681"></a>01681 <span class="comment">             the mss (the minumum of the MSS and the available</span>
<a name="l01682"></a>01682 <span class="comment">             window). */</span>
<a name="l01683"></a>01683           <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> &gt; uip_connr-&gt;mss) {
<a name="l01684"></a>01684             <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = uip_connr-&gt;mss;
<a name="l01685"></a>01685           }
<a name="l01686"></a>01686 
<a name="l01687"></a>01687           <span class="comment">/* Remember how much data we send out now so that we know</span>
<a name="l01688"></a>01688 <span class="comment">             when everything has been acknowledged. */</span>
<a name="l01689"></a>01689           uip_connr-&gt;len = <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a>;
<a name="l01690"></a>01690         } <span class="keywordflow">else</span> {
<a name="l01691"></a>01691 
<a name="l01692"></a>01692           <span class="comment">/* If the application already had unacknowledged data, we</span>
<a name="l01693"></a>01693 <span class="comment">             make sure that the application does not send (i.e.,</span>
<a name="l01694"></a>01694 <span class="comment">             retransmit) out more than it previously sent out. */</span>
<a name="l01695"></a>01695           <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = uip_connr-&gt;len;
<a name="l01696"></a>01696         }
<a name="l01697"></a>01697       }
<a name="l01698"></a>01698       uip_connr-&gt;nrtx = 0;
<a name="l01699"></a>01699     apprexmit:
<a name="l01700"></a>01700       <a class="code" href="a00150.html#g561b8eda32e059d4e7397f776268cc63">uip_appdata</a> = <a class="code" href="a00150.html#ga05a3dde2048480fa3ab2a5961898d18">uip_sappdata</a>;
<a name="l01701"></a>01701       
<a name="l01702"></a>01702       <span class="comment">/* If the application has data to be sent, or if the incoming</span>
<a name="l01703"></a>01703 <span class="comment">         packet had new data in it, we must send out a packet. */</span>
<a name="l01704"></a>01704       <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> &gt; 0 &amp;&amp; uip_connr-&gt;len &gt; 0) {
<a name="l01705"></a>01705         <span class="comment">/* Add the length of the IP and TCP headers. */</span>
<a name="l01706"></a>01706         <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = uip_connr-&gt;len + <a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a>;
<a name="l01707"></a>01707         <span class="comment">/* We always set the ACK flag in response packets. */</span>
<a name="l01708"></a>01708         <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a> | <a class="code" href="a00150.html#g1320fd0006a2f70138bc2d0018dda829">TCP_PSH</a>;
<a name="l01709"></a>01709         <span class="comment">/* Send the packet. */</span>
<a name="l01710"></a>01710         <span class="keywordflow">goto</span> tcp_send_noopts;
<a name="l01711"></a>01711       }
<a name="l01712"></a>01712       <span class="comment">/* If there is no data to send, just send out a pure ACK if</span>
<a name="l01713"></a>01713 <span class="comment">         there is newdata. */</span>
<a name="l01714"></a>01714       <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; <a class="code" href="a00150.html#g39ce739bd352d7e348e37395ce903e43">UIP_NEWDATA</a>) {
<a name="l01715"></a>01715         <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00150.html#gee37386b2ab828787c05227eb109def7">UIP_TCPIP_HLEN</a>;
<a name="l01716"></a>01716         <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l01717"></a>01717         <span class="keywordflow">goto</span> tcp_send_noopts;
<a name="l01718"></a>01718       }
<a name="l01719"></a>01719     }
<a name="l01720"></a>01720     <span class="keywordflow">goto</span> drop;
<a name="l01721"></a>01721   <span class="keywordflow">case</span> <a class="code" href="a00150.html#gd135fb0cfdfb2c212f0f51865a3640e4">UIP_LAST_ACK</a>:
<a name="l01722"></a>01722     <span class="comment">/* We can close this connection if the peer has acknowledged our</span>
<a name="l01723"></a>01723 <span class="comment">       FIN. This is indicated by the UIP_ACKDATA flag. */</span>
<a name="l01724"></a>01724     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; UIP_ACKDATA) {
<a name="l01725"></a>01725       uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#g28eda870cff3d8e3cf2949e6f57a502b">UIP_CLOSED</a>;
<a name="l01726"></a>01726       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = UIP_CLOSE;
<a name="l01727"></a>01727       <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01728"></a>01728     }
<a name="l01729"></a>01729     <span class="keywordflow">break</span>;
<a name="l01730"></a>01730     
<a name="l01731"></a>01731   <span class="keywordflow">case</span> <a class="code" href="a00150.html#ga533c394b1fa0030205534befa31c525">UIP_FIN_WAIT_1</a>:
<a name="l01732"></a>01732     <span class="comment">/* The application has closed the connection, but the remote host</span>
<a name="l01733"></a>01733 <span class="comment">       hasn't closed its end yet. Thus we do nothing but wait for a</span>
<a name="l01734"></a>01734 <span class="comment">       FIN from the other side. */</span>
<a name="l01735"></a>01735     <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt; 0) {
<a name="l01736"></a>01736       uip_add_rcv_nxt(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>);
<a name="l01737"></a>01737     }
<a name="l01738"></a>01738     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g88e60aa2cf23e1c65d630701db08c743">TCP_FIN</a>) {
<a name="l01739"></a>01739       <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; UIP_ACKDATA) {
<a name="l01740"></a>01740         uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#gfff0ed43201bf1e2020de1a0d6cac070">UIP_TIME_WAIT</a>;
<a name="l01741"></a>01741         uip_connr-&gt;timer = 0;
<a name="l01742"></a>01742         uip_connr-&gt;len = 0;
<a name="l01743"></a>01743       } <span class="keywordflow">else</span> {
<a name="l01744"></a>01744         uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#g64d9affc680a445d708234e70450477b">UIP_CLOSING</a>;
<a name="l01745"></a>01745       }
<a name="l01746"></a>01746       uip_add_rcv_nxt(1);
<a name="l01747"></a>01747       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = UIP_CLOSE;
<a name="l01748"></a>01748       <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01749"></a>01749       <span class="keywordflow">goto</span> tcp_send_ack;
<a name="l01750"></a>01750     } <span class="keywordflow">else</span> <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; UIP_ACKDATA) {
<a name="l01751"></a>01751       uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#g160128ab5d2ea3cc497b91ee4eb4ef99">UIP_FIN_WAIT_2</a>;
<a name="l01752"></a>01752       uip_connr-&gt;len = 0;
<a name="l01753"></a>01753       <span class="keywordflow">goto</span> drop;
<a name="l01754"></a>01754     }
<a name="l01755"></a>01755     <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt; 0) {
<a name="l01756"></a>01756       <span class="keywordflow">goto</span> tcp_send_ack;
<a name="l01757"></a>01757     }
<a name="l01758"></a>01758     <span class="keywordflow">goto</span> drop;
<a name="l01759"></a>01759       
<a name="l01760"></a>01760   <span class="keywordflow">case</span> <a class="code" href="a00150.html#g160128ab5d2ea3cc497b91ee4eb4ef99">UIP_FIN_WAIT_2</a>:
<a name="l01761"></a>01761     <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt; 0) {
<a name="l01762"></a>01762       uip_add_rcv_nxt(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>);
<a name="l01763"></a>01763     }
<a name="l01764"></a>01764     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags &amp; <a class="code" href="a00150.html#g88e60aa2cf23e1c65d630701db08c743">TCP_FIN</a>) {
<a name="l01765"></a>01765       uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#gfff0ed43201bf1e2020de1a0d6cac070">UIP_TIME_WAIT</a>;
<a name="l01766"></a>01766       uip_connr-&gt;timer = 0;
<a name="l01767"></a>01767       uip_add_rcv_nxt(1);
<a name="l01768"></a>01768       <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = UIP_CLOSE;
<a name="l01769"></a>01769       <a class="code" href="a00153.html#g41aa744caa46913b3b3aedb2a4e78546">UIP_APPCALL</a>();
<a name="l01770"></a>01770       <span class="keywordflow">goto</span> tcp_send_ack;
<a name="l01771"></a>01771     }
<a name="l01772"></a>01772     <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt; 0) {
<a name="l01773"></a>01773       <span class="keywordflow">goto</span> tcp_send_ack;
<a name="l01774"></a>01774     }
<a name="l01775"></a>01775     <span class="keywordflow">goto</span> drop;
<a name="l01776"></a>01776 
<a name="l01777"></a>01777   <span class="keywordflow">case</span> <a class="code" href="a00150.html#gfff0ed43201bf1e2020de1a0d6cac070">UIP_TIME_WAIT</a>:
<a name="l01778"></a>01778     <span class="keywordflow">goto</span> tcp_send_ack;
<a name="l01779"></a>01779     
<a name="l01780"></a>01780   <span class="keywordflow">case</span> <a class="code" href="a00150.html#g64d9affc680a445d708234e70450477b">UIP_CLOSING</a>:
<a name="l01781"></a>01781     <span class="keywordflow">if</span>(<a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> &amp; UIP_ACKDATA) {
<a name="l01782"></a>01782       uip_connr-&gt;tcpstateflags = <a class="code" href="a00150.html#gfff0ed43201bf1e2020de1a0d6cac070">UIP_TIME_WAIT</a>;
<a name="l01783"></a>01783       uip_connr-&gt;timer = 0;
<a name="l01784"></a>01784     }
<a name="l01785"></a>01785   }
<a name="l01786"></a>01786   <span class="keywordflow">goto</span> drop;
<a name="l01787"></a>01787   
<a name="l01788"></a>01788 
<a name="l01789"></a>01789   <span class="comment">/* We jump here when we are ready to send the packet, and just want</span>
<a name="l01790"></a>01790 <span class="comment">     to set the appropriate TCP sequence numbers in the TCP header. */</span>
<a name="l01791"></a>01791  tcp_send_ack:
<a name="l01792"></a>01792   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flags = <a class="code" href="a00150.html#g44b3b1ab31a403ba28ec135adfcbefef">TCP_ACK</a>;
<a name="l01793"></a>01793  tcp_send_nodata:
<a name="l01794"></a>01794   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <a class="code" href="a00150.html#g15f2617f7dc1713f9d10282125c6027b">UIP_IPTCPH_LEN</a>;
<a name="l01795"></a>01795  tcp_send_noopts:
<a name="l01796"></a>01796   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpoffset = (<a class="code" href="a00150.html#g17d111686f98e4c09db73a770ac3f1a4">UIP_TCPH_LEN</a> / 4) &lt;&lt; 4;
<a name="l01797"></a>01797  tcp_send:
<a name="l01798"></a>01798   <span class="comment">/* We're done with the input processing. We are now ready to send a</span>
<a name="l01799"></a>01799 <span class="comment">     reply. Our job is to fill in all the fields of the TCP and IP</span>
<a name="l01800"></a>01800 <span class="comment">     headers before calculating the checksum and finally send the</span>
<a name="l01801"></a>01801 <span class="comment">     packet. */</span>
<a name="l01802"></a>01802   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[0] = uip_connr-&gt;rcv_nxt[0];
<a name="l01803"></a>01803   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[1] = uip_connr-&gt;rcv_nxt[1];
<a name="l01804"></a>01804   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[2] = uip_connr-&gt;rcv_nxt[2];
<a name="l01805"></a>01805   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ackno[3] = uip_connr-&gt;rcv_nxt[3];
<a name="l01806"></a>01806   
<a name="l01807"></a>01807   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[0] = uip_connr-&gt;snd_nxt[0];
<a name="l01808"></a>01808   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[1] = uip_connr-&gt;snd_nxt[1];
<a name="l01809"></a>01809   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[2] = uip_connr-&gt;snd_nxt[2];
<a name="l01810"></a>01810   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;seqno[3] = uip_connr-&gt;snd_nxt[3];
<a name="l01811"></a>01811 
<a name="l01812"></a>01812   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;proto = <a class="code" href="a00150.html#g517c770991459cc62dc009c0d3875c6a">UIP_PROTO_TCP</a>;
<a name="l01813"></a>01813   
<a name="l01814"></a>01814   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcport  = uip_connr-&gt;lport;
<a name="l01815"></a>01815   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destport = uip_connr-&gt;rport;
<a name="l01816"></a>01816 
<a name="l01817"></a>01817   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;srcipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>);
<a name="l01818"></a>01818   <a class="code" href="a00148.html#g769512993b7b27271909d6daa4748b60">uip_ipaddr_copy</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;destipaddr, uip_connr-&gt;ripaddr);
<a name="l01819"></a>01819 
<a name="l01820"></a>01820   <span class="keywordflow">if</span>(uip_connr-&gt;tcpstateflags &amp; <a class="code" href="a00150.html#gde29ec025e6754afd8cc24c954a8dec8">UIP_STOPPED</a>) {
<a name="l01821"></a>01821     <span class="comment">/* If the connection has issued uip_stop(), we advertise a zero</span>
<a name="l01822"></a>01822 <span class="comment">       window so that the remote host will stop sending data. */</span>
<a name="l01823"></a>01823     <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;wnd[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;wnd[1] = 0;
<a name="l01824"></a>01824   } <span class="keywordflow">else</span> {
<a name="l01825"></a>01825     <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;wnd[0] = ((<a class="code" href="a00153.html#g5b9dba2123705bce1ce95c3deca0bdad">UIP_RECEIVE_WINDOW</a>) &gt;&gt; 8);
<a name="l01826"></a>01826     <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;wnd[1] = ((<a class="code" href="a00153.html#g5b9dba2123705bce1ce95c3deca0bdad">UIP_RECEIVE_WINDOW</a>) &amp; 0xff);
<a name="l01827"></a>01827   }
<a name="l01828"></a>01828 
<a name="l01829"></a>01829  tcp_send_noconn:
<a name="l01830"></a>01830   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ttl = <a class="code" href="a00153.html#gb61381673de27f31848c5396bf0b338e">UIP_TTL</a>;
<a name="l01831"></a>01831 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l01832"></a>01832 <span class="preprocessor"></span>  <span class="comment">/* For IPv6, the IP length field does not include the IPv6 IP header</span>
<a name="l01833"></a>01833 <span class="comment">     length. */</span>
<a name="l01834"></a>01834   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] = ((<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> - UIP_IPH_LEN) &gt;&gt; 8);
<a name="l01835"></a>01835   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1] = ((<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> - UIP_IPH_LEN) &amp; 0xff);
<a name="l01836"></a>01836 <span class="preprocessor">#else </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l01837"></a>01837   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] = (<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &gt;&gt; 8);
<a name="l01838"></a>01838   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1] = (<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &amp; 0xff);
<a name="l01839"></a>01839 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l01840"></a>01840 
<a name="l01841"></a>01841   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;urgp[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;urgp[1] = 0;
<a name="l01842"></a>01842   
<a name="l01843"></a>01843   <span class="comment">/* Calculate TCP checksum. */</span>
<a name="l01844"></a>01844   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpchksum = 0;
<a name="l01845"></a>01845   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcpchksum = ~(<a class="code" href="a00150.html#g85b65e38aa74eba18979156f97a94a87">uip_tcpchksum</a>());
<a name="l01846"></a>01846   
<a name="l01847"></a>01847  ip_send_nolen:
<a name="l01848"></a>01848 
<a name="l01849"></a>01849 <span class="preprocessor">#if UIP_CONF_IPV6</span>
<a name="l01850"></a>01850 <span class="preprocessor"></span>  <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;vtc = 0x60;
<a name="l01851"></a>01851   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tcflow = 0x00;
<a name="l01852"></a>01852   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;flow = 0x00;
<a name="l01853"></a>01853 <span class="preprocessor">#else </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l01854"></a>01854   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;vhl = 0x45;
<a name="l01855"></a>01855   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;tos = 0;
<a name="l01856"></a>01856   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipoffset[1] = 0;
<a name="l01857"></a>01857   ++ipid;
<a name="l01858"></a>01858   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipid[0] = ipid &gt;&gt; 8;
<a name="l01859"></a>01859   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipid[1] = ipid &amp; 0xff;
<a name="l01860"></a>01860   <span class="comment">/* Calculate IP checksum. */</span>
<a name="l01861"></a>01861   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipchksum = 0;
<a name="l01862"></a>01862   <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ipchksum = ~(<a class="code" href="a00150.html#g2addf34c7d457c1a7899a7e2171ef1e9">uip_ipchksum</a>());
<a name="l01863"></a>01863   <a class="code" href="a00135.html#534d9e416324fb8ecca6b9cb4b1f6a6a">DEBUG_PRINTF</a>(<span class="stringliteral">"uip ip_send_nolen: chkecum 0x%04x\n"</span>, <a class="code" href="a00150.html#g2addf34c7d457c1a7899a7e2171ef1e9">uip_ipchksum</a>());
<a name="l01864"></a>01864 <span class="preprocessor">#endif </span><span class="comment">/* UIP_CONF_IPV6 */</span>
<a name="l01865"></a>01865    
<a name="l01866"></a>01866   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#e292b8977f6b81265bf14e1676face3e">tcp</a>.<a class="code" href="a00093.html#dc69abadd5aa07c7d74f9292db2cd93c">sent</a>);
<a name="l01867"></a>01867  send:
<a name="l01868"></a>01868   <a class="code" href="a00135.html#534d9e416324fb8ecca6b9cb4b1f6a6a">DEBUG_PRINTF</a>(<span class="stringliteral">"Sending packet with length %d (%d)\n"</span>, <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a>,
<a name="l01869"></a>01869                (<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[0] &lt;&lt; 8) | <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;len[1]);
<a name="l01870"></a>01870   
<a name="l01871"></a>01871   <a class="code" href="a00150.html#g9c0814ed491fa452ec97910c0728d410">UIP_STAT</a>(++<a class="code" href="a00150.html#g9ee50a40597e67fce96541ab56c3b712">uip_stat</a>.<a class="code" href="a00093.html#1deb2899508216804823498a69378118">ip</a>.<a class="code" href="a00093.html#dc69abadd5aa07c7d74f9292db2cd93c">sent</a>);
<a name="l01872"></a>01872   <span class="comment">/* Return and let the caller do the actual transmission. */</span>
<a name="l01873"></a>01873   <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = 0;
<a name="l01874"></a>01874   <span class="keywordflow">return</span>;
<a name="l01875"></a>01875  drop:
<a name="l01876"></a>01876   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = 0;
<a name="l01877"></a>01877   <a class="code" href="a00150.html#gb4ef6b00924990e7a293f66715b6d1d1">uip_flags</a> = 0;
<a name="l01878"></a>01878   <span class="keywordflow">return</span>;
<a name="l01879"></a>01879 }
<a name="l01880"></a>01880 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l01881"></a>01881 <a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a>
<a name="l01882"></a><a class="code" href="a00150.html#ga22b04cac8cf283ca12f028578bebc06">01882</a> <a class="code" href="a00148.html#ga22b04cac8cf283ca12f028578bebc06">htons</a>(<a class="code" href="a00153.html#g77570ac4fcab86864fa1916e55676da2">u16_t</a> val)
<a name="l01883"></a>01883 {
<a name="l01884"></a>01884   <span class="keywordflow">return</span> <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(val);
<a name="l01885"></a>01885 }
<a name="l01886"></a>01886 <span class="comment">/*---------------------------------------------------------------------------*/</span>
<a name="l01887"></a>01887 <span class="keywordtype">void</span>
<a name="l01888"></a><a class="code" href="a00150.html#g04b053a623aac7cd4195157d470661b3">01888</a> <a class="code" href="a00147.html#g04b053a623aac7cd4195157d470661b3">uip_send</a>(<span class="keyword">const</span> <span class="keywordtype">void</span> *data, <span class="keywordtype">int</span> len)
<a name="l01889"></a>01889 {
<a name="l01890"></a>01890   <span class="keywordflow">if</span>(len &gt; 0) {
<a name="l01891"></a>01891     <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a> = len;
<a name="l01892"></a>01892     <span class="keywordflow">if</span>(data != <a class="code" href="a00150.html#ga05a3dde2048480fa3ab2a5961898d18">uip_sappdata</a>) {
<a name="l01893"></a>01893       memcpy(<a class="code" href="a00150.html#ga05a3dde2048480fa3ab2a5961898d18">uip_sappdata</a>, (data), <a class="code" href="a00150.html#g5b5615dc240daed20949c0fded2b4679">uip_slen</a>);
<a name="l01894"></a>01894     }
<a name="l01895"></a>01895   }
<a name="l01896"></a>01896 }<span class="comment"></span>
<a name="l01897"></a>01897 <span class="comment">/** @} */</span>
</pre></div><hr size="1"><address style="align: right;"><small>Generated on Mon Jun 12 10:23:01 2006 for uIP 1.0 by&nbsp;
<a href="http://www.doxygen.org/index.html">
<img src="doxygen.png" alt="doxygen" align="middle" border="0"></a> 1.4.6 </small></address>
</body>
</html>