summaryrefslogtreecommitdiffstats
path: root/usr.sbin/mrouted/mtrace.c
blob: c129b464796cb6832eaffc71ae69d5dee931da0c (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
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
/*
 * mtrace.c
 *
 * This tool traces the branch of a multicast tree from a source to a
 * receiver for a particular multicast group and gives statistics
 * about packet rate and loss for each hop along the path.  It can
 * usually be invoked just as
 *
 * 	mtrace source
 *
 * to trace the route from that source to the local host for a default
 * group when only the route is desired and not group-specific packet
 * counts.  See the usage line for more complex forms.
 *
 *
 * Released 4 Apr 1995.  This program was adapted by Steve Casner
 * (USC/ISI) from a prototype written by Ajit Thyagarajan (UDel and
 * Xerox PARC).  It attempts to parallel in command syntax and output
 * format the unicast traceroute program written by Van Jacobson (LBL)
 * for the parts where that makes sense.
 * 
 * Copyright (c) 1995 by the University of Southern California
 * All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation in source and binary forms for any purposes and without
 * fee is hereby granted, provided that the above copyright notice
 * appear in all copies and that both the copyright notice and this
 * permission notice appear in supporting documentation, and that any
 * documentation, advertising materials, and other materials related to
 * such distribution and use acknowledge that the software was developed
 * by the University of Southern California, Information Sciences
 * Institute.  The name of the University may not be used to endorse or
 * promote products derived from this software without specific prior
 * written permission.
 *
 * THE UNIVERSITY OF SOUTHERN CALIFORNIA makes no representations about
 * the suitability of this software for any purpose.  THIS SOFTWARE IS
 * PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Other copyrights might apply to parts of this software and are so
 * noted when applicable.
 *
 * Parts of this software are derived from mrouted, which has the
 * following license:
 * 
 * The mrouted program is covered by the following license.  Use of the
 * mrouted program represents acceptance of these terms and conditions.
 * 
 * 1. STANFORD grants to LICENSEE a nonexclusive and nontransferable
 * license to use, copy and modify the computer software ``mrouted''
 * (hereinafter called the ``Program''), upon the terms and conditions
 * hereinafter set out and until Licensee discontinues use of the Licensed
 * Program.
 * 
 * 2. LICENSEE acknowledges that the Program is a research tool still in
 * the development state, that it is being supplied ``as is,'' without any
 * accompanying services from STANFORD, and that this license is entered
 * into in order to encourage scientific collaboration aimed at further
 * development and application of the Program.
 * 
 * 3. LICENSEE may copy the Program and may sublicense others to use
 * object code copies of the Program or any derivative version of the
 * Program.  All copies must contain all copyright and other proprietary
 * notices found in the Program as provided by STANFORD.  Title to
 * copyright to the Program remains with STANFORD.
 * 
 * 4. LICENSEE may create derivative versions of the Program.  LICENSEE
 * hereby grants STANFORD a royalty-free license to use, copy, modify,
 * distribute and sublicense any such derivative works.  At the time
 * LICENSEE provides a copy of a derivative version of the Program to a
 * third party, LICENSEE shall provide STANFORD with one copy of the
 * source code of the derivative version at no charge to STANFORD.
 * 
 * 5. STANFORD MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
 * IMPLIED.  By way of example, but not limitation, STANFORD MAKES NO
 * REPRESENTATION OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
 * PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED PROGRAM WILL NOT
 * INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS. STANFORD
 * shall not be held liable for any liability nor for any direct, indirect
 * or consequential damages with respect to any claim by LICENSEE or any
 * third party on account of or arising from this Agreement or use of the
 * Program.
 * 
 * 6. This agreement shall be construed, interpreted and applied in
 * accordance with the State of California and any legal action arising
 * out of this Agreement or use of the Program shall be filed in a court
 * in the State of California.
 * 
 * 7. Nothing in this Agreement shall be construed as conferring rights to
 * use in advertising, publicity or otherwise any trademark or the name
 * of ``Stanford''.
 * 
 * The mrouted program is COPYRIGHT 1989 by The Board of Trustees of
 * Leland Stanford Junior University.
 *
 *
 * The mtrace program has been modified and improved by Xerox
 * Corporation.  Xerox grants to LICENSEE a non-exclusive and
 * non-transferable license to use, copy, and modify the Xerox modified
 * and improved mrouted software on the same terms and conditions which
 * govern the license Stanford and ISI grant with respect to the mtrace
 * program.  These terms and conditions are incorporated in this grant
 * by reference and shall be deemed to have been accepted by LICENSEE
 * to cover its relationship with Xerox Corporation with respect to any
 * use of the Xerox improved program.
 * 
 * The mtrace program is COPYRIGHT 1998 by Xerox Corporation.
 *
 */

#ifndef lint
static const char rcsid[] =
  "$FreeBSD$";
#endif

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <memory.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/igmp.h>
#include <sys/ioctl.h>
#ifdef SYSV
#include <sys/sockio.h>
#endif
#include <arpa/inet.h>
#ifdef __STDC__
#include <stdarg.h>
#else
#include <varargs.h>
#endif
#ifdef SUNOS5
#include <sys/systeminfo.h>
#endif

typedef unsigned int u_int32;	/* XXX */
#include "mtrace.h"

#define DEFAULT_TIMEOUT	3	/* How long to wait before retrying requests */
#define DEFAULT_RETRIES 3	/* How many times to try */
#define DEFAULT_EXTRAHOPS 3	/* How many hops past a non-responding rtr */
#define MAXHOPS 60		/* Don't need more hops than this */
#define UNICAST_TTL 255		/* TTL for unicast response */
#define MULTICAST_TTL1 127	/* Default TTL for multicast query/response */
#define MULTICAST_TTL_INC 32	/* TTL increment for increase after timeout */
#define MULTICAST_TTL_MAX 192	/* Maximum TTL allowed (protect low-BW links */

#define TRUE 1
#define FALSE 0
#define DVMRP_ASK_NEIGHBORS2	5	/* DVMRP msg requesting neighbors */
#define DVMRP_NEIGHBORS2	6	/* reply to above */
#define DVMRP_NF_DOWN		0x10	/* kernel state of interface */
#define DVMRP_NF_DISABLED	0x20	/* administratively disabled */
#define MAX_IP_PACKET_LEN	576
#define MIN_IP_HEADER_LEN	20
#define MAX_IP_HEADER_LEN	60
#define MAX_DVMRP_DATA_LEN \
		( MAX_IP_PACKET_LEN - MAX_IP_HEADER_LEN - IGMP_MINLEN )

struct resp_buf {
    u_long qtime;		/* Time query was issued */
    u_long rtime;		/* Time response was received */
    int	len;			/* Number of reports or length of data */
    struct igmp igmp;		/* IGMP header */
    union {
	struct {
	    struct tr_query q;		/* Query/response header */
	    struct tr_resp r[MAXHOPS];	/* Per-hop reports */
	} t;
	char d[MAX_DVMRP_DATA_LEN];	/* Neighbor data */
    } u;
} base, incr[2];

#define qhdr u.t.q
#define resps u.t.r
#define ndata u.d

char *names[MAXHOPS];

/*
 * In mrouted 3.3 and 3.4 (and in some Cisco IOS releases),
 * cache entries can get deleted even if there is traffic
 * flowing, which will reset the per-source/group counters.
 */
#define		BUG_RESET	0x01

/*
 * Also in mrouted 3.3 and 3.4, there's a bug in neighbor
 * version processing which can cause them to believe that
 * the neighbor is constantly resetting.  This causes them
 * to constantly delete all their state.
 */
#define		BUG_RESET2X	0x02

/*
 * Pre-3.7 mrouted's forget to byte-swap their reports.
 */
#define		BUG_SWAP	0x04

/*
 * Pre-3.9 mrouted's forgot a parenthesis in the htonl()
 * on the time calculation so supply bogus times.
 */
#define		BUG_BOGUSTIME	0x08

#define BUG_NOPRINT	(BUG_RESET | BUG_RESET2X)

int bugs[MAXHOPS];			/* List of bugs noticed at each hop */

struct mtrace {
	struct mtrace	*next;
	struct resp_buf	 base, incr[2];
	struct resp_buf	*new, *prev;
	int		 nresp;
	struct timeval	 last;
	int		 bugs[MAXHOPS];
	char		*names[MAXHOPS];
	int		 lastqid;
};

int timeout = DEFAULT_TIMEOUT;
int nqueries = DEFAULT_RETRIES;
int numeric = FALSE;
int debug = 0;
int passive = FALSE;
int multicast = FALSE;
int unicast = FALSE;
int statint = 10;
int verbose = FALSE;
int tunstats = FALSE;
int weak = FALSE;
int extrahops = DEFAULT_EXTRAHOPS;
int printstats = TRUE;
int sendopts = TRUE;
int lossthresh = 0;
int fflag = FALSE;
int staticqid = 0;

u_int32 defgrp;				/* Default group if not specified */
u_int32 query_cast;			/* All routers multicast addr */
u_int32 resp_cast;			/* Mtrace response multicast addr */

u_int32 lcl_addr = 0;			/* This host address, in NET order */
u_int32 dst_netmask = 0;		/* netmask to go with qdst */

/*
 * Query/response parameters, all initialized to zero and set later
 * to default values or from options.
 */
u_int32 qsrc = 0;		/* Source address in the query */
u_int32 qgrp = 0;		/* Group address in the query */
u_int32 qdst = 0;		/* Destination (receiver) address in query */
u_char qno  = 0;		/* Max number of hops to query */
u_int32 raddr = 0;		/* Address where response should be sent */
int    qttl = 0;		/* TTL for the query packet */
u_char rttl = 0;		/* TTL for the response packet */
u_int32 gwy = 0;		/* User-supplied last-hop router address */
u_int32 tdst = 0;		/* Address where trace is sent (last-hop) */

char s1[19];		/* buffers to hold the string representations  */
char s2[19];		/* of IP addresses, to be passed to inet_fmt() */
char s3[19];		/* or inet_fmts().                             */

#if !(defined(BSD) && (BSD >= 199103))
extern int		errno;
extern int		sys_nerr;
extern char *		sys_errlist[];
#endif

#define RECV_BUF_SIZE 8192
char	*send_buf, *recv_buf;
int	igmp_socket;
u_int32	allrtrs_group;
char	router_alert[4];	     	/* Router Alert IP Option	    */
#ifndef	IPOPT_RA
#define	IPOPT_RA		148
#endif
#ifdef SUNOS5
char	eol[4];		     		/* EOL IP Option		    */
int ip_addlen = 0;		     	/* Workaround for Option bug #2     */
#endif

/*
 * max macro, with weird case to avoid conflicts
 */
#define	MaX(a,b)	((a) > (b) ? (a) : (b))

#ifndef __P
#ifdef __STDC__
#define __P(x)	x
#else
#define __P(x)	()
#endif
#endif

typedef int (*callback_t) __P((int, u_char *, int, struct igmp *, int,
			struct sockaddr *, int *, struct timeval *));

void			init_igmp __P((void));
void			send_igmp __P((u_int32 src, u_int32 dst, int type,
						int code, u_int32 group,
						int datalen));
int			inet_cksum __P((u_short *addr, u_int len));
void			k_set_rcvbuf __P((int bufsize));
void			k_hdr_include __P((int bool));
void			k_set_ttl __P((int t));
void			k_set_loop __P((int l));
void			k_set_if __P((u_int32 ifa));
void			k_join __P((u_int32 grp, u_int32 ifa));
void			k_leave __P((u_int32 grp, u_int32 ifa));
char *			inet_fmt __P((u_int32 addr, char *s));
char *			inet_fmts __P((u_int32 addr, u_int32 mask, char *s));
char *			inet_name __P((u_int32 addr));
u_int32			host_addr __P((char *name));
/* u_int is promoted u_char */
char *			proto_type __P((u_int type));
char *			flag_type __P((u_int type));

u_int32			get_netmask __P((int s, u_int32 *dst));
int			get_ttl __P((struct resp_buf *buf));
int			t_diff __P((u_long a, u_long b));
u_long			byteswap __P((u_long v));
int			mtrace_callback __P((int, u_char *, int, struct igmp *,
					int, struct sockaddr *, int *,
					struct timeval *));
int			send_recv __P((u_int32 dst, int type, int code,
					int tries, struct resp_buf *save,
					callback_t callback));
void			passive_mode __P((void));
char *			print_host __P((u_int32 addr));
char *			print_host2 __P((u_int32 addr1, u_int32 addr2));
void			print_trace __P((int idx, struct resp_buf *buf,
					char **names));
int			what_kind __P((struct resp_buf *buf, char *why));
char *			scale __P((int *hop));
void			stat_line __P((struct tr_resp *r, struct tr_resp *s,
					int have_next, int *res));
void			fixup_stats __P((struct resp_buf *base,
					struct resp_buf *prev,
					struct resp_buf *new,
					int *bugs));
int			check_thresh __P((int thresh,
					struct resp_buf *base,
					struct resp_buf *prev,
					struct resp_buf *new));
int			print_stats __P((struct resp_buf *base,
					struct resp_buf *prev,
					struct resp_buf *new,
					int *bugs,
					char **names));
int			path_changed __P((struct resp_buf *base,
					struct resp_buf *new));
void			check_vif_state __P((void));

int			main __P((int argc, char *argv[]));
void			log __P((int, int, char *, ...));
static void		usage __P((void));


/*
 * Open and initialize the igmp socket, and fill in the non-changing
 * IP header fields in the output packet buffer.
 */
void
init_igmp()
{
    struct ip *ip;

    recv_buf = (char *)malloc(RECV_BUF_SIZE);
    if (recv_buf == 0)
	log(LOG_ERR, 0, "Out of memory allocating recv_buf!");
    send_buf = (char *)malloc(RECV_BUF_SIZE);
    if (send_buf == 0)
	log(LOG_ERR, 0, "Out of memory allocating send_buf!");

    if ((igmp_socket = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP)) < 0) 
	log(LOG_ERR, errno, "IGMP socket");

    k_hdr_include(TRUE);	/* include IP header when sending */
    k_set_rcvbuf(48*1024);	/* lots of input buffering        */
    k_set_ttl(1);		/* restrict multicasts to one hop */
    k_set_loop(FALSE);		/* disable multicast loopback     */

    ip         = (struct ip *)send_buf;
    ip->ip_hl  = sizeof(struct ip) >> 2;
    ip->ip_v   = IPVERSION;
    ip->ip_tos = 0;
    ip->ip_off = 0;
    ip->ip_p   = IPPROTO_IGMP;
    ip->ip_ttl = MAXTTL;	/* applies to unicasts only */

#ifndef INADDR_ALLRTRS_GROUP
#define	INADDR_ALLRTRS_GROUP	0xe0000002	/* 224.0.0.2 */
#endif
    allrtrs_group  = htonl(INADDR_ALLRTRS_GROUP);

    router_alert[0] = IPOPT_RA;	/* Router Alert */
    router_alert[1] = 4;	/* 4 bytes */
    router_alert[2] = 0;
    router_alert[3] = 0;
}

#ifdef SUNOS5
void
checkforsolarisbug()
{
    u_int32 localhost = htonl(0x7f000001);

    eol[0] = IPOPT_EOL;
    eol[1] = IPOPT_EOL;
    eol[2] = IPOPT_EOL;
    eol[3] = IPOPT_EOL;

    setsockopt(igmp_socket, IPPROTO_IP, IP_OPTIONS, eol, sizeof(eol));
    /*
     * Check if the kernel adds the options length to the packet
     * length.  Send myself an IGMP packet of type 0 (illegal),
     * with 4 IPOPT_EOL options, my PID (for collision detection)
     * and 4 bytes of zero (so that the checksum works whether
     * the 4 bytes of zero get truncated or not).
     */
    bzero(send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN, 8);
    *(int *)(send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN) = getpid();
    send_igmp(localhost, localhost, 0, 0, 0, 8);
    while (1) {
	int recvlen, dummy = 0;

	recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
				0, NULL, &dummy);
	/* 8 == 4 bytes of options and 4 bytes of PID */
	if (recvlen >= MIN_IP_HEADER_LEN + IGMP_MINLEN + 8) {
	    struct ip *ip = (struct ip *)recv_buf;
	    struct igmp *igmp;
	    int *p;

	    if (ip->ip_hl != 6 ||
		ip->ip_p != IPPROTO_IGMP ||
	        ip->ip_src.s_addr != localhost ||
		ip->ip_dst.s_addr != localhost)
		continue;

	    igmp = (struct igmp *)(recv_buf + (ip->ip_hl << 2));
	    if (igmp->igmp_group.s_addr != 0)
		continue;
	    if (igmp->igmp_type != 0 || igmp->igmp_code != 0)
		continue;

	    p = (int *)((char *)igmp + IGMP_MINLEN);
	    if (*p != getpid())
		continue;

#ifdef RAW_INPUT_IS_RAW
	    ip->ip_len = ntohs(ip->ip_len);
#endif
	    if (ip->ip_len == IGMP_MINLEN + 4)
		ip_addlen = 4;
	    else if (ip->ip_len == IGMP_MINLEN + 8)
		ip_addlen = 0;
	    else
		log(LOG_ERR, 0, "while checking for Solaris bug: Sent %d bytes and got back %d!", IGMP_MINLEN + 8, ip->ip_len);

	    break;
	}
    }
}
#endif

/*
 * Construct an IGMP message in the output packet buffer.  The caller may
 * have already placed data in that buffer, of length 'datalen'.  Then send
 * the message from the interface with IP address 'src' to destination 'dst'.
 */
void
send_igmp(src, dst, type, code, group, datalen)
    u_int32 src, dst;
    int type, code;
    u_int32 group;
    int datalen;
{
    struct sockaddr_in sdst;
    struct ip *ip;
    struct igmp *igmp;
    int setloop = 0;
    static int raset = 0;
    int sendra = 0;
    int sendlen;

    ip                      = (struct ip *)send_buf;
    ip->ip_src.s_addr       = src;
    ip->ip_dst.s_addr       = dst;
    ip->ip_len              = MIN_IP_HEADER_LEN + IGMP_MINLEN + datalen;
    sendlen		    = ip->ip_len;
#ifdef SUNOS5
    ip->ip_len		   += ip_addlen;
#endif
#ifdef RAW_OUTPUT_IS_RAW
    ip->ip_len		    = htons(ip->ip_len);
#endif

    igmp                    = (struct igmp *)(send_buf + MIN_IP_HEADER_LEN);
    igmp->igmp_type         = type;
    igmp->igmp_code         = code;
    igmp->igmp_group.s_addr = group;
    igmp->igmp_cksum        = 0;
    igmp->igmp_cksum        = inet_cksum((u_short *)igmp,
					 IGMP_MINLEN + datalen);

    if (IN_MULTICAST(ntohl(dst))) {
	k_set_if(src);
	setloop = 1;
	k_set_loop(TRUE);
	if (dst != allrtrs_group)
	    sendra = 1;
    }

    if (sendopts && sendra && !raset) {
	setsockopt(igmp_socket, IPPROTO_IP, IP_OPTIONS,
			router_alert, sizeof(router_alert));
	raset = 1;
    } else if (!sendra && raset) {
#ifdef SUNOS5
	/*
	 * SunOS5 < 5.6 cannot properly reset the IP_OPTIONS "socket"
	 * option.  Instead, set up a string of 4 EOL's.
	 */
	setsockopt(igmp_socket, IPPROTO_IP, IP_OPTIONS,
			eol, sizeof(eol));
#else
	setsockopt(igmp_socket, IPPROTO_IP, IP_OPTIONS,
			NULL, 0);
#endif
	raset = 0;
    }

    bzero(&sdst, sizeof(sdst));
    sdst.sin_family = AF_INET;
#if (defined(BSD) && (BSD >= 199103))
    sdst.sin_len = sizeof(sdst);
#endif
    sdst.sin_addr.s_addr = dst;
    if (sendto(igmp_socket, send_buf, sendlen, 0,
			(struct sockaddr *)&sdst, sizeof(sdst)) < 0) {
	    log(LOG_WARNING, errno, "sendto to %s on %s",
		inet_fmt(dst, s1), inet_fmt(src, s2));
    }

    if (setloop)
	    k_set_loop(FALSE);

    log(LOG_DEBUG, 0, "SENT %s from %-15s to %s",
	type == IGMP_MTRACE ? "mtrace request" : "ask_neighbors",
	src == INADDR_ANY ? "INADDR_ANY" : inet_fmt(src, s1),
	inet_fmt(dst, s2));
}

/*
 * inet_cksum extracted from:
 *			P I N G . C
 *
 * Author -
 *	Mike Muuss
 *	U. S. Army Ballistic Research Laboratory
 *	December, 1983
 * Modified at Uc Berkeley
 *
 * (ping.c) Status -
 *	Public Domain.  Distribution Unlimited.
 *
 *			I N _ C K S U M
 *
 * Checksum routine for Internet Protocol family headers (C Version)
 *
 */
int
inet_cksum(addr, len)
	u_short *addr;
	u_int len;
{
	register int nleft = (int)len;
	register u_short *w = addr;
	u_short answer = 0;
	register int sum = 0;

	/*
	 *  Our algorithm is simple, using a 32 bit accumulator (sum),
	 *  we add sequential 16 bit words to it, and at the end, fold
	 *  back all the carry bits from the top 16 bits into the lower
	 *  16 bits.
	 */
	while (nleft > 1)  {
		sum += *w++;
		nleft -= 2;
	}

	/* mop up an odd byte, if necessary */
	if (nleft == 1) {
		*(u_char *) (&answer) = *(u_char *)w ;
		sum += answer;
	}

	/*
	 * add back carry outs from top 16 bits to low 16 bits
	 */
	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
	sum += (sum >> 16);			/* add carry */
	answer = ~sum;				/* truncate to 16 bits */
	return (answer);
}

void
k_set_rcvbuf(bufsize)
    int bufsize;
{
    if (setsockopt(igmp_socket, SOL_SOCKET, SO_RCVBUF,
		   (char *)&bufsize, sizeof(bufsize)) < 0)
	log(LOG_ERR, errno, "setsockopt SO_RCVBUF %u", bufsize);
}


void
k_hdr_include(bool)
    int bool;
{
#ifdef IP_HDRINCL
    if (setsockopt(igmp_socket, IPPROTO_IP, IP_HDRINCL,
		   (char *)&bool, sizeof(bool)) < 0)
	log(LOG_ERR, errno, "setsockopt IP_HDRINCL %u", bool);
#endif
}

void
k_set_ttl(t)
    int t;
{
    u_char ttl;

    ttl = t;
    if (setsockopt(igmp_socket, IPPROTO_IP, IP_MULTICAST_TTL,
		   (char *)&ttl, sizeof(ttl)) < 0)
	log(LOG_ERR, errno, "setsockopt IP_MULTICAST_TTL %u", ttl);
}


void
k_set_loop(l)
    int l;
{
    u_char loop;

    loop = l;
    if (setsockopt(igmp_socket, IPPROTO_IP, IP_MULTICAST_LOOP,
		   (char *)&loop, sizeof(loop)) < 0)
	log(LOG_ERR, errno, "setsockopt IP_MULTICAST_LOOP %u", loop);
}

void
k_set_if(ifa)
    u_int32 ifa;
{
    struct in_addr adr;

    adr.s_addr = ifa;
    if (setsockopt(igmp_socket, IPPROTO_IP, IP_MULTICAST_IF,
		   (char *)&adr, sizeof(adr)) < 0)
	log(LOG_ERR, errno, "setsockopt IP_MULTICAST_IF %s",
	    		    inet_fmt(ifa, s1));
}

void
k_join(grp, ifa)
    u_int32 grp;
    u_int32 ifa;
{
    struct ip_mreq mreq;

    mreq.imr_multiaddr.s_addr = grp;
    mreq.imr_interface.s_addr = ifa;

    if (setsockopt(igmp_socket, IPPROTO_IP, IP_ADD_MEMBERSHIP,
		   (char *)&mreq, sizeof(mreq)) < 0)
	log(LOG_WARNING, errno, "can't join group %s on interface %s",
				inet_fmt(grp, s1), inet_fmt(ifa, s2));
}


void
k_leave(grp, ifa)
    u_int32 grp;
    u_int32 ifa;
{
    struct ip_mreq mreq;

    mreq.imr_multiaddr.s_addr = grp;
    mreq.imr_interface.s_addr = ifa;

    if (setsockopt(igmp_socket, IPPROTO_IP, IP_DROP_MEMBERSHIP,
		   (char *)&mreq, sizeof(mreq)) < 0)
	log(LOG_WARNING, errno, "can't leave group %s on interface %s",
				inet_fmt(grp, s1), inet_fmt(ifa, s2));
}

/*
 * Convert an IP address in u_long (network) format into a printable string.
 */
char *
inet_fmt(addr, s)
    u_int32 addr;
    char *s;
{
    register u_char *a;

    a = (u_char *)&addr;
    sprintf(s, "%u.%u.%u.%u", a[0], a[1], a[2], a[3]);
    return (s);
}


/*
 * Convert an IP subnet number in u_long (network) format into a printable
 * string including the netmask as a number of bits.
 */
char *
inet_fmts(addr, mask, s)
    u_int32 addr, mask;
    char *s;
{
    register u_char *a, *m;
    int bits;

    if ((addr == 0) && (mask == 0)) {
	sprintf(s, "default");
	return (s);
    }
    a = (u_char *)&addr;
    m = (u_char *)&mask;
    bits = 33 - ffs(ntohl(mask));

    if      (m[3] != 0) sprintf(s, "%u.%u.%u.%u/%d", a[0], a[1], a[2], a[3],
						bits);
    else if (m[2] != 0) sprintf(s, "%u.%u.%u/%d",    a[0], a[1], a[2], bits);
    else if (m[1] != 0) sprintf(s, "%u.%u/%d",       a[0], a[1], bits);
    else                sprintf(s, "%u/%d",          a[0], bits);

    return (s);
}

char   *
inet_name(addr)
    u_int32  addr;
{
    struct hostent *e;

    e = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET);

    return e ? e->h_name : "?";
}


u_int32 
host_addr(name)
    char   *name;
{
    struct hostent *e = (struct hostent *)0;
    u_int32  addr;
    int	i, dots = 3;
    char	buf[40];
    char	*ip = name;
    char	*op = buf;

    /*
     * Undo BSD's favor -- take fewer than 4 octets as net/subnet address
     * if the name is all numeric.
     */
    for (i = sizeof(buf) - 7; i > 0; --i) {
	if (*ip == '.') --dots;
	else if (*ip == '\0') break;
	else if (!isdigit(*ip)) dots = 0;  /* Not numeric, don't add zeroes */
	*op++ = *ip++;
    }
    for (i = 0; i < dots; ++i) {
	*op++ = '.';
	*op++ = '0';
    }
    *op = '\0';

    if (dots <= 0)
	e = gethostbyname(name);
    if (e && (e->h_length == sizeof(addr))) {
	memcpy((char *)&addr, e->h_addr_list[0], e->h_length);
	if (e->h_addr_list[1])
	    fprintf(stderr, "Warning: %s has multiple addresses, using %s\n",
			name, inet_fmt(addr, s1));
    } else {
	addr = inet_addr(buf);
	if (addr == -1 || (IN_MULTICAST(addr) && dots)) {
	    addr = 0;
	    printf("Could not parse %s as host name or address\n", name);
	}
    }
    return addr;
}


char *
proto_type(type)
    u_int type;
{
    static char buf[80];

    switch (type) {
      case PROTO_DVMRP:
	return ("DVMRP");
      case PROTO_MOSPF:
	return ("MOSPF");
      case PROTO_PIM:
	return ("PIM");
      case PROTO_CBT:
	return ("CBT");
      case PROTO_PIM_SPECIAL:
	return ("PIM/Special");
      case PROTO_PIM_STATIC:
	return ("PIM/Static");
      case PROTO_DVMRP_STATIC:
	return ("DVMRP/Static");
      case PROTO_PIM_BGP4PLUS:
	return ("PIM/BGP4+");
      case PROTO_CBT_SPECIAL:
	return ("CBT/Special");
      case PROTO_CBT_STATIC:
	return ("CBT/Static");
      case PROTO_PIM_ASSERT:
	return ("PIM/Assert");
      case 0:
	return ("None");
      default:
	(void) sprintf(buf, "Unknown protocol code %d", type);
	return (buf);
    }
}


char *
flag_type(type)
    u_int type;
{
    static char buf[80];

    switch (type) {
      case TR_NO_ERR:
	return ("");
      case TR_WRONG_IF:
	return ("Wrong interface");
      case TR_PRUNED:
	return ("Prune sent upstream");
      case TR_OPRUNED:
	return ("Output pruned");
      case TR_SCOPED:
	return ("Hit scope boundary");
      case TR_NO_RTE:
	return ("No route");
      case TR_NO_FWD:
	return ("Not forwarding");
      case TR_HIT_RP:
	return ("Reached RP/Core");
      case TR_RPF_IF:
	return ("RPF Interface");
      case TR_NO_MULTI:
	return ("Multicast disabled");
      case TR_OLD_ROUTER:
	return ("Next router no mtrace");
      case TR_NO_SPACE:
	return ("No space in packet");
      case TR_ADMIN_PROHIB:
	return ("Admin. Prohibited");
      default:
	(void) sprintf(buf, "Unknown error code %d", type);
	return (buf);
    }
}    

/*
 * If destination is on a local net, get the netmask, else set the
 * netmask to all ones.  There are two side effects: if the local
 * address was not explicitly set, and if the destination is on a
 * local net, use that one; in either case, verify that the local
 * address is valid.
 */
u_int32
get_netmask(s, dst)
    int s;
    u_int32 *dst;
{
    unsigned int n;
    struct ifconf ifc;
    struct ifreq *ifrp, *ifend;
    u_int32 if_addr, if_mask;
    u_int32 retval = 0xFFFFFFFF;
    int found = FALSE;
    int num_ifreq = 32;

    ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
    ifc.ifc_buf = malloc(ifc.ifc_len);
    while (ifc.ifc_buf) {
	if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {
	    perror("ioctl SIOCGIFCONF");
	    return retval;
	}

	/*
	 * If the buffer was large enough to hold all the addresses
	 * then break out, otherwise increase the buffer size and
	 * try again.
	 *
	 * The only way to know that we definitely had enough space
	 * is to know that there was enough space for at least one
	 * more struct ifreq. ???
	 */
	if ((num_ifreq * sizeof(struct ifreq)) >=
	     ifc.ifc_len + sizeof(struct ifreq))
	     break;

	num_ifreq *= 2;
	ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
	ifc.ifc_buf = realloc(ifc.ifc_buf, ifc.ifc_len);
    }
    if (ifc.ifc_buf == NULL) {
	fprintf(stderr, "getting interface list: ran out of memory");
	exit(1);
    }

    ifrp = (struct ifreq *)ifc.ifc_buf;
    ifend = (struct ifreq *)(ifc.ifc_buf + ifc.ifc_len);
    /*
     * Loop through all of the interfaces.
     */
    for (; ifrp < ifend && !found; ifrp = (struct ifreq *)((char *)ifrp + n)) {
#if BSD >= 199006
	n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
	if (n < sizeof(*ifrp))
	    n = sizeof(*ifrp);
#else
	n = sizeof(*ifrp);
#endif
	/*
	 * Ignore any interface for an address family other than IP.
	 */
	if (ifrp->ifr_addr.sa_family != AF_INET)
	    continue;

	if_addr = ((struct sockaddr_in *)&(ifrp->ifr_addr))->sin_addr.s_addr;
	if (ioctl(s, SIOCGIFFLAGS, (char *)ifrp) < 0) {
	    fprintf(stderr, "SIOCGIFFLAGS on ");
	    perror(ifrp->ifr_name);
	    continue;
	}
	if ((ifrp->ifr_flags & (IFF_MULTICAST|IFF_UP|IFF_LOOPBACK)) !=
				(IFF_MULTICAST|IFF_UP))
	    continue;
	if (*dst == 0)
	    *dst = if_addr;
	if (ioctl(s, SIOCGIFNETMASK, (char *)ifrp) >= 0) {
	    if_mask = ((struct sockaddr_in *)&(ifrp->ifr_addr))->sin_addr.s_addr;
	    if (if_mask != 0 && (*dst & if_mask) == (if_addr & if_mask)) {
		retval = if_mask;
		if (lcl_addr == 0) lcl_addr = if_addr;	/* XXX what about aliases? */
	    }
	}
	if (lcl_addr == if_addr) found = TRUE;
    }
    if (!found && lcl_addr != 0) {
	printf("Interface address is not valid\n");
	exit(1);
    }
    return (retval);
}


/*
 * Try to pick a TTL that will get past all the thresholds in the path.
 */
int
get_ttl(buf)
    struct resp_buf *buf;
{
    int rno;
    struct tr_resp *b;
    u_int ttl;

    if (buf && (rno = buf->len) > 0) {
	b = buf->resps + rno - 1;
	ttl = b->tr_fttl;

	while (--rno > 0) {
	    --b;
	    if (ttl < b->tr_fttl) ttl = b->tr_fttl;
	    else ++ttl;
	}
	ttl += MULTICAST_TTL_INC;
	if (ttl < MULTICAST_TTL1) ttl = MULTICAST_TTL1;
	if (ttl > MULTICAST_TTL_MAX) ttl = MULTICAST_TTL_MAX;
	return (ttl);
    } else return(MULTICAST_TTL1);
}

/*
 * Calculate the difference between two 32-bit NTP timestamps and return
 * the result in milliseconds.
 */
int
t_diff(a, b)
    u_long a, b;
{
    int d = a - b;

    return ((d * 125) >> 13);
}

/*
 * Swap bytes for poor little-endian machines that don't byte-swap
 */
u_long
byteswap(v)
    u_long v;
{
    return ((v << 24) | ((v & 0xff00) << 8) |
	    ((v >> 8) & 0xff00) | (v >> 24));
}

#if 0
/*
 * XXX incomplete - need private callback data, too?
 * XXX since dst doesn't get passed through?
 */
int
neighbors_callback(tmo, buf, buflen, igmp, igmplen, addr, addrlen, ts)
    int tmo;
    u_char *buf;
    int buflen;
    struct igmp *igmp;
    int igmplen;
    struct sockaddr *addr;
    int *addrlen;
    struct timeval *ts;
{
    int len;
    u_int32 dst;
    struct ip *ip = (struct ip *)buf;

    if (tmo)
	return 0;

    if (igmp->igmp_code != DVMRP_NEIGHBORS2)
	return 0;
    len = igmplen;
    /*
     * Accept DVMRP_NEIGHBORS2 response if it comes from the
     * address queried or if that address is one of the local
     * addresses in the response.
     */
    if (ip->ip_src.s_addr != dst) {
	u_int32 *p = (u_int32 *)(igmp + 1);
	u_int32 *ep = p + (len >> 2);
	while (p < ep) {
	    u_int32 laddr = *p++;
	    int n = ntohl(*p++) & 0xFF;
	    if (laddr == dst) {
		ep = p + 1;		/* ensure p < ep after loop */
		break;
	    }
	    p += n;
	}
	if (p >= ep)
	    return 0;
    }
    return buflen;
}
#endif

int
mtrace_callback(tmo, buf, buflen, igmp, igmplen, addr, addrlen, ts)
    int tmo;
    u_char *buf;
    int buflen;
    struct igmp *igmp;
    int igmplen;
    struct sockaddr *addr;
    int *addrlen;
    struct timeval *ts;
{
    static u_char *savbuf = NULL;
    static int savbuflen;
    static struct sockaddr *savaddr;
    static int savaddrlen;
    static struct timeval savts;

    int len = (igmplen - QLEN) / RLEN;
    struct tr_resp *r = (struct tr_resp *)((struct tr_query *)(igmp + 1) + 1);

    if (tmo == 1) {
	/*
	 * If we timed out with a packet saved, then return that packet.
	 * send_recv won't send this same packet to the callback again.
	 */
	if (savbuf) {
	    bcopy(savbuf, buf, savbuflen);
	    free(savbuf);
	    savbuf = NULL;
	    bcopy(savaddr, addr, savaddrlen);
	    free(savaddr);
	    *addrlen = savaddrlen;
	    bcopy(&savts, ts, sizeof(savts));
	    return savbuflen;
	}
	return 0;
    }
    if (savbuf) {
	free(savbuf);
	savbuf = NULL;
	free(savaddr);
    }
    /*
     * Check for IOS bug described in CSCdi68628, where a router that does
     *  not have multicast enabled responds to an mtrace request with a 1-hop
     *  error packet.
     * Heuristic is:
     *  If there is only one hop reported in the packet,
     *	And the protocol code is 0,
     *  And there is no previous hop,
     *	And the forwarding information is "Not Forwarding",
     *	And the router is not on the same subnet as the destination of the
     *		trace,
     *  then drop this packet.  The "#if 0"'d code saves it and returns
     *   it on timeout, but timeouts are too common (e.g. routers with
     *   limited unicast routing tables, etc).
     */
    if (len == 1 && r->tr_rproto == 0 && r->tr_rmtaddr == 0 &&
					r->tr_rflags == TR_NO_FWD) {
	u_int32 smask;

	VAL_TO_MASK(smask, r->tr_smask);
	if ((r->tr_outaddr & smask) != (qdst & smask)) {
#if 0
	    /* XXX should do this silently? */
	    fprintf(stderr, "mtrace: probably IOS-buggy packet from %s\n",
		inet_fmt(((struct sockaddr_in *)addr)->sin_addr.s_addr, s1));
	    /* Save the packet to return if a timeout occurs. */
	    savbuf = (u_char *)malloc(buflen);
	    if (savbuf != NULL) {
		bcopy(buf, savbuf, buflen);
		savbuflen = buflen;
		savaddr = (struct sockaddr *)malloc(*addrlen);
		if (savaddr != NULL) {
		    bcopy(addr, savaddr, *addrlen);
		    savaddrlen = *addrlen;
		    bcopy(ts, &savts, sizeof(savts));
		} else {
		    free(savbuf);
		    savbuf = NULL;
		}
	    }
#endif
	    return 0;
	}
    }
    return buflen;
}

int
send_recv(dst, type, code, tries, save, callback)
    u_int32 dst;
    int type, code, tries;
    struct resp_buf *save;
    callback_t callback;
{
    fd_set  fds;
    struct timeval tq, tr, tv;
    struct ip *ip;
    struct igmp *igmp;
    struct tr_query *query, *rquery;
    struct tr_resp *r;
    struct sockaddr_in recvaddr;
    u_int32 local, group;
    int ipdatalen, iphdrlen, igmpdatalen;
    int datalen;
    int count, recvlen, socklen = sizeof(recvaddr);
    int len;
    int i;

    if (type == IGMP_MTRACE) {
	group = qgrp;
	datalen = sizeof(struct tr_query);
    } else {
	group = htonl(0xff03);
	datalen = 0;
    }
    if (IN_MULTICAST(ntohl(dst))) local = lcl_addr;
    else local = INADDR_ANY;

    /*
     * If the reply address was not explictly specified, start off
     * with the standard multicast reply address, or the unicast
     * address of this host if the unicast flag was specified.
     * Then, if there is no response after trying half the tries
     * with multicast, switch to the unicast address of this host
     * if the multicast flag was not specified.  If the TTL was
     * also not specified, set a multicast TTL and increase it
     * for every try.
     */
    query = (struct tr_query *)(send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN);
    query->tr_raddr = raddr ? raddr : unicast ? lcl_addr : resp_cast;
    TR_SETTTL(query->tr_rttlqid, rttl ? rttl :
      IN_MULTICAST(ntohl(query->tr_raddr)) ? get_ttl(save) : UNICAST_TTL);
    query->tr_src   = qsrc;
    query->tr_dst   = qdst;

    for (i = tries ; i > 0; --i) {
	int oqid;

	if (tries == nqueries && raddr == 0) {
	    if (i == (nqueries >> 1)) {
		if (multicast && unicast) {
		    query->tr_raddr = resp_cast;
		    if (!rttl)
			TR_SETTTL(query->tr_rttlqid, get_ttl(save));
		} else if (!multicast) {
		    query->tr_raddr = lcl_addr;
		    TR_SETTTL(query->tr_rttlqid, UNICAST_TTL);
		}
	    }
	    if (i < tries && IN_MULTICAST(ntohl(query->tr_raddr)) &&
								rttl == 0) {
		TR_SETTTL(query->tr_rttlqid,
			TR_GETTTL(query->tr_rttlqid) + MULTICAST_TTL_INC);
		if (TR_GETTTL(query->tr_rttlqid) > MULTICAST_TTL_MAX)
		  TR_SETTTL(query->tr_rttlqid, MULTICAST_TTL_MAX);
	    }
	}

	/*
	 * Change the qid for each request sent to avoid being confused
	 * by duplicate responses
	 */
	oqid = TR_GETQID(query->tr_rttlqid);
	if (staticqid)
	    TR_SETQID(query->tr_rttlqid, staticqid);
	else
#ifdef SYSV    
	    TR_SETQID(query->tr_rttlqid, ((u_int32)lrand48() >> 8));
#else
	    TR_SETQID(query->tr_rttlqid, ((u_int32)arc4random() >> 8));
#endif

	/*
	 * Set timer to calculate delays, then send query
	 */
	gettimeofday(&tq, 0);
	send_igmp(local, dst, type, code, group, datalen);

	/*
	 * Wait for response, discarding false alarms
	 */
	while (TRUE) {
	    if (igmp_socket >= FD_SETSIZE)
		    log(LOG_ERR, 0, "descriptor too big");
	    FD_ZERO(&fds);
	    FD_SET(igmp_socket, &fds);
	    gettimeofday(&tv, 0);
	    tv.tv_sec = tq.tv_sec + timeout - tv.tv_sec;
	    tv.tv_usec = tq.tv_usec - tv.tv_usec;
	    if (tv.tv_usec < 0) tv.tv_usec += 1000000L, --tv.tv_sec;
	    if (tv.tv_sec < 0) tv.tv_sec = tv.tv_usec = 0;

	    count = select(igmp_socket + 1, &fds, (fd_set *)0, (fd_set *)0,
			   &tv);

	    if (count < 0) {
		if (errno != EINTR) warn("select");
		continue;
	    } else if (count == 0) {
		/*
		 * Timed out.  Notify the callback.
		 */
		if (!callback || (recvlen = (callback)(1, recv_buf, 0, NULL, 0, (struct sockaddr *)&recvaddr, &socklen, &tr)) == 0) {
		    printf("* ");
		    fflush(stdout);
		    break;
		}
	    } else {
		/*
		 * Data is available on the socket, so read it.
		 */
		gettimeofday(&tr, 0);
		recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
				   0, (struct sockaddr *)&recvaddr, &socklen);
	    }

	    if (recvlen <= 0) {
		if (recvlen && errno != EINTR) warn("recvfrom");
		continue;
	    }

	    if (recvlen < sizeof(struct ip)) {
		warnx("packet too short (%u bytes) for IP header", recvlen);
		continue;
	    }
	    ip = (struct ip *) recv_buf;
	    if (ip->ip_p == 0)	/* ignore cache creation requests */
		continue;

	    iphdrlen = ip->ip_hl << 2;
#ifdef RAW_INPUT_IS_RAW
	    ipdatalen = ntohs(ip->ip_len);
#else
	    ipdatalen = ip->ip_len;
#endif
	    if (iphdrlen + ipdatalen != recvlen) {
		warnx("packet shorter (%u bytes) than hdr+data len (%u+%u)",
			recvlen, iphdrlen, ipdatalen);
		continue;
	    }

	    igmp = (struct igmp *) (recv_buf + iphdrlen);
	    igmpdatalen = ipdatalen - IGMP_MINLEN;
	    if (igmpdatalen < 0) {
		warnx("IP data field too short (%u bytes) for IGMP from %s",
			ipdatalen, inet_fmt(ip->ip_src.s_addr, s1));
		continue;
	    }

	    switch (igmp->igmp_type) {

	      case IGMP_DVMRP:
		if (type != IGMP_DVMRP || code != DVMRP_ASK_NEIGHBORS2)
			continue;
		if (igmp->igmp_code != DVMRP_NEIGHBORS2) continue;
		len = igmpdatalen;
		/*
		 * Accept DVMRP_NEIGHBORS2 response if it comes from the
		 * address queried or if that address is one of the local
		 * addresses in the response.
		 */
		if (ip->ip_src.s_addr != dst) {
		    u_int32 *p = (u_int32 *)(igmp + 1);
		    u_int32 *ep = p + (len >> 2);
		    while (p < ep) {
			u_int32 laddr = *p++;
			int n = ntohl(*p++) & 0xFF;
			if (laddr == dst) {
			    ep = p + 1;		/* ensure p < ep after loop */
			    break;
			}
			p += n;
		    }
		    if (p >= ep) continue;
		}
		break;

	      case IGMP_MTRACE:	    /* For backward compatibility with 3.3 */
	      case IGMP_MTRACE_RESP:
		if (type != IGMP_MTRACE) continue;
		if (igmpdatalen <= QLEN) continue;
		if ((igmpdatalen - QLEN)%RLEN) {
		    printf("packet with incomplete responses (%d bytes)\n",
			igmpdatalen);
		    continue;
		}

		/*
		 * Ignore responses that don't match query.
		 */
		rquery = (struct tr_query *)(igmp + 1);
		if (rquery->tr_src != qsrc || rquery->tr_dst != qdst)
		    continue;
		if (TR_GETQID(rquery->tr_rttlqid) !=
			TR_GETQID(query->tr_rttlqid)) {
		    if (verbose && TR_GETQID(rquery->tr_rttlqid) == oqid)
			printf("[D]");
		    continue;
		}
		len = (igmpdatalen - QLEN)/RLEN;
		r = (struct tr_resp *)(rquery+1) + len - 1;

		/*
		 * Ignore trace queries passing through this node when
		 * mtrace is run on an mrouter that is in the path
		 * (needed only because IGMP_MTRACE is accepted above
		 * for backward compatibility with multicast release 3.3).
		 */
		if (igmp->igmp_type == IGMP_MTRACE) {
		    u_int32 smask;

		    VAL_TO_MASK(smask, r->tr_smask);
		    if (len < code && (r->tr_inaddr & smask) != (qsrc & smask)
			&& r->tr_rmtaddr != 0 && !(r->tr_rflags & 0x80))
		      continue;
		}
		/*
		 * Some routers will return error messages without
		 * filling in their addresses.  We fill in the address
		 * for them.
		 */
		if (r->tr_outaddr == 0)
		    r->tr_outaddr = recvaddr.sin_addr.s_addr;

		/*
		 * A match, we'll keep this one.
		 */
		if (len > code) {
		    warnx("num hops received (%d) exceeds request (%d)",
			    len, code);
		}
		rquery->tr_raddr = query->tr_raddr;	/* Insure these are */
		TR_SETTTL(rquery->tr_rttlqid, TR_GETTTL(query->tr_rttlqid));
							/* as we sent them */
		break;

	      default:
		continue;
	    }

	    /*
	     * We're pretty sure we want to use this packet now,
	     * but if the caller gave a callback function, it might
	     * want to handle it instead.  Give the callback a chance,
	     * unless the select timed out (in which case the only way
	     * to get here is because the callback returned a packet).
	     */
	    if (callback && (count != 0) && ((callback)(0, recv_buf, recvlen, igmp, igmpdatalen, (struct sockaddr*)&recvaddr, &socklen, &tr)) == 0) {
		/*
		 * The callback function didn't like this packet.
		 * Go try receiving another one.
		 */
		continue;
	    }

	    /*
	     * Most of the sanity checking done at this point.
	     * Return this packet we have been waiting for.
	     */
	    if (save) {
		save->qtime = ((tq.tv_sec + JAN_1970) << 16) +
			      (tq.tv_usec << 10) / 15625;
		save->rtime = ((tr.tv_sec + JAN_1970) << 16) +
			      (tr.tv_usec << 10) / 15625;
		save->len = len;
		bcopy((char *)igmp, (char *)&save->igmp, ipdatalen);
	    }
	    return (recvlen);
	}
    }
    return (0);
}

/*
 * Most of this code is duplicated elsewhere.  I'm not sure if
 * the duplication is absolutely required or not.
 *
 * Ideally, this would keep track of ongoing statistics
 * collection and print out statistics.  (& keep track
 * of h-b-h traces and only print the longest)  For now,
 * it just snoops on what traces it can.
 */
void
passive_mode()
{
    struct timeval tr;
    time_t tr_sec;
    struct ip *ip;
    struct igmp *igmp;
    struct tr_resp *r;
    struct sockaddr_in recvaddr;
    struct tm *now;
    char timebuf[32];
    int socklen;
    int ipdatalen, iphdrlen, igmpdatalen;
    int len, recvlen;
    int qid;
    u_int32 smask;
    struct mtrace *remembered = NULL, *m, *n, **nn;
    int pc = 0;

    if (raddr) {
	if (IN_MULTICAST(ntohl(raddr))) k_join(raddr, lcl_addr);
    } else k_join(htonl(0xE0000120), lcl_addr);

    while (1) {
	fflush(stdout);		/* make sure previous trace is flushed */

	socklen = sizeof(recvaddr);
	recvlen = recvfrom(igmp_socket, recv_buf, RECV_BUF_SIZE,
			   0, (struct sockaddr *)&recvaddr, &socklen);
	gettimeofday(&tr,0);

	if (recvlen <= 0) {
	    if (recvlen && errno != EINTR) warn("recvfrom");
	    continue;
	}

	if (recvlen < sizeof(struct ip)) {
	    warnx("packet too short (%u bytes) for IP header", recvlen);
	    continue;
	}
	ip = (struct ip *) recv_buf;
	if (ip->ip_p == 0)	/* ignore cache creation requests */
	    continue;

	iphdrlen = ip->ip_hl << 2;
#ifdef RAW_INPUT_IS_RAW
	ipdatalen = ntohs(ip->ip_len);
#else
	ipdatalen = ip->ip_len;
#endif
	if (iphdrlen + ipdatalen != recvlen) {
	    warnx("packet shorter (%u bytes) than hdr+data len (%u+%u)",
		    recvlen, iphdrlen, ipdatalen);
	    continue;
	}

	igmp = (struct igmp *) (recv_buf + iphdrlen);
	igmpdatalen = ipdatalen - IGMP_MINLEN;
	if (igmpdatalen < 0) {
	    warnx("IP data field too short (%u bytes) for IGMP from %s",
		    ipdatalen, inet_fmt(ip->ip_src.s_addr, s1));
	    continue;
	}

	switch (igmp->igmp_type) {

	  case IGMP_MTRACE:	    /* For backward compatibility with 3.3 */
	  case IGMP_MTRACE_RESP:
	    if (igmpdatalen < QLEN) continue;
	    if ((igmpdatalen - QLEN)%RLEN) {
		printf("packet with incorrect datalen\n");
		continue;
	    }

	    len = (igmpdatalen - QLEN)/RLEN;

	    break;

	  default:
	    continue;
	}

	base.qtime = ((tr.tv_sec + JAN_1970) << 16) +
		      (tr.tv_usec << 10) / 15625;
	base.rtime = ((tr.tv_sec + JAN_1970) << 16) +
		      (tr.tv_usec << 10) / 15625;
	base.len = len;
	bcopy((char *)igmp, (char *)&base.igmp, ipdatalen);
	/*
	 * If the user specified which traces to monitor,
	 * only accept traces that correspond to the
	 * request
	 */
	if ((qsrc != 0 && qsrc != base.qhdr.tr_src) ||
	    (qdst != 0 && qdst != base.qhdr.tr_dst) ||
	    (qgrp != 0 && qgrp != igmp->igmp_group.s_addr))
	    continue;

	/* XXX This should be a hash table */
	/* XXX garbage-collection should be more efficient */
	for (nn = &remembered, n = *nn, m = 0; n; n = *nn) {
	    if ((n->base.qhdr.tr_src == base.qhdr.tr_src) &&
		(n->base.qhdr.tr_dst == base.qhdr.tr_dst) &&
		(n->base.igmp.igmp_group.s_addr == igmp->igmp_group.s_addr)) {
		m = n;
		m->last = tr;
	    }
	    if (tr.tv_sec - n->last.tv_sec > 500) { /* XXX don't hardcode */
		*nn = n->next;
		free(n);
	    } else {
		nn = &n->next;
	    }
	}

	tr_sec = tr.tv_sec;
	now = localtime(&tr_sec);
	strftime(timebuf, sizeof(timebuf) - 1, "%b %e %k:%M:%S", now);
	printf("Mtrace %s at %s",
		len == 0 ? "query" :
			   igmp->igmp_type == IGMP_MTRACE_RESP ? "response" :
								 "in transit",
		timebuf);
	if (len == 0)
		printf(" by %s", inet_fmt(recvaddr.sin_addr.s_addr, s1));
	if (!IN_MULTICAST(base.qhdr.tr_raddr))
		printf(", resp to %s", (len == 0 && recvaddr.sin_addr.s_addr == base.qhdr.tr_raddr) ? "same" : inet_fmt(base.qhdr.tr_raddr, s1));
	else
		printf(", respttl %d", TR_GETTTL(base.qhdr.tr_rttlqid));
	printf(", qid %06x\n", qid = TR_GETQID(base.qhdr.tr_rttlqid));
	printf("packet from %s to %s\n",
		inet_fmt(ip->ip_src.s_addr, s1),
		inet_fmt(ip->ip_dst.s_addr, s2));

	printf("from %s to %s via group %s (mxhop=%d)\n",
		inet_fmt(base.qhdr.tr_dst, s1), inet_fmt(base.qhdr.tr_src, s2),
		inet_fmt(igmp->igmp_group.s_addr, s3), igmp->igmp_code);
	if (len == 0) {
	    printf("\n");
	    continue;
	}
	r = base.resps + base.len - 1;
	/*
	 * Some routers will return error messages without
	 * filling in their addresses.  We fill in the address
	 * for them.
	 */
	if (r->tr_outaddr == 0)
	    r->tr_outaddr = recvaddr.sin_addr.s_addr;

	/*
	 * If there was a previous trace, it see if this is a
	 * statistics candidate.
	 */
	if (m && base.len == m->base.len &&
		!(pc = path_changed(&m->base, &base))) {
	    /*
	     * Some mtrace responders send multiple copies of the same
	     * reply.  Skip this packet if it's got the same query-id
	     * as the last one.
	     */
	    if (m->lastqid == qid) {
		printf("Skipping duplicate reply\n");
		continue;
	    }

	    m->lastqid = qid;

	    ++m->nresp;

	    bcopy(&base, m->new, sizeof(base));

	    printf("Results after %d seconds:\n\n",
		   (int)((m->new->qtime - m->base.qtime) >> 16));
	    fixup_stats(&m->base, m->prev, m->new, m->bugs);
	    print_stats(&m->base, m->prev, m->new, m->bugs, m->names);
	    m->prev = m->new;
	    m->new = &m->incr[(m->nresp & 1)];

	    continue;
	}

	if (m == NULL) {
	    m = (struct mtrace *)malloc(sizeof(struct mtrace));
	    if (m == NULL) {
		fprintf(stderr, "Out of memory!\n");
		continue;
	    }
	    bzero(m, sizeof(struct mtrace));
	    m->next = remembered;
	    remembered = m;
	    bcopy(&tr, &m->last, sizeof(tr));
	}

	/* Either it's a hop-by-hop in progress, or the path changed. */
	if (pc) {
	    printf("[Path Changed...]\n");
	    bzero(m->bugs, sizeof(m->bugs));
	}
	bcopy(&base, &m->base, sizeof(base));
	m->prev = &m->base;
	m->new = &m->incr[0];
	m->nresp = 0;

	printf("  0  ");
	print_host(base.qhdr.tr_dst);
	printf("\n");
	print_trace(1, &base, m->names);
	VAL_TO_MASK(smask, r->tr_smask);
	if ((r->tr_inaddr & smask) == (base.qhdr.tr_src & smask)) {
	    printf("%3d  ", -(base.len+1));
	    print_host(base.qhdr.tr_src);
	    printf("\n");
	} else if (r->tr_rmtaddr != 0) {
	    printf("%3d  ", -(base.len+1));
	    print_host(r->tr_rmtaddr);
	    printf(" %s\n", r->tr_rflags == TR_OLD_ROUTER ?
				   "doesn't support mtrace"
				 : "is the next hop");
	}
	printf("\n");
    }
}

char *
print_host(addr)
    u_int32 addr;
{
    return print_host2(addr, 0);
}

/*
 * On some routers, one interface has a name and the other doesn't.
 * We always print the address of the outgoing interface, but can
 * sometimes get the name from the incoming interface.  This might be
 * confusing but should be slightly more helpful than just a "?".
 */
char *
print_host2(addr1, addr2)
    u_int32 addr1, addr2;
{
    char *name;

    if (numeric) {
	printf("%s", inet_fmt(addr1, s1));
	return ("");
    }
    name = inet_name(addr1);
    if (*name == '?' && *(name + 1) == '\0' && addr2 != 0)
	name = inet_name(addr2);
    printf("%s (%s)", name, inet_fmt(addr1, s1));
    return (name);
}

/*
 * Print responses as received (reverse path from dst to src)
 */
void
print_trace(idx, buf, names)
    int idx;
    struct resp_buf *buf;
    char **names;
{
    struct tr_resp *r;
    char *name;
    int i;
    int hop;
    char *ms;

    i = abs(idx);
    r = buf->resps + i - 1;

    for (; i <= buf->len; ++i, ++r) {
	if (idx > 0) printf("%3d  ", -i);
	name = print_host2(r->tr_outaddr, r->tr_inaddr);
	if (r->tr_rflags != TR_NO_RTE)
	    printf("  %s  thresh^ %d", proto_type(r->tr_rproto), r->tr_fttl);
	if (verbose) {
	    hop = t_diff(ntohl(r->tr_qarr), buf->qtime);
	    ms = scale(&hop);
	    printf("  %d%s", hop, ms);
	}
	printf("  %s", flag_type(r->tr_rflags));
	if (i > 1 && r->tr_outaddr != (r-1)->tr_rmtaddr) {
	    printf(" !RPF!");
	    print_host((r-1)->tr_rmtaddr);
	}
	if (r->tr_rflags != TR_NO_RTE) {
	    if (r->tr_smask <= 1)    /* MASK_TO_VAL() returns 1 for default */
		printf(" [default]");
	    else if (verbose) {
		u_int32 smask;

		VAL_TO_MASK(smask, r->tr_smask);
		printf(" [%s]", inet_fmts(buf->qhdr.tr_src & smask,
							smask, s1));
	    }
	}
	printf("\n");
	if (names[i-1])
	    free(names[i-1]);
	names[i-1]=malloc(strlen(name) + 1);
	strcpy(names[i-1], name);
    }
}

/*
 * See what kind of router is the next hop
 */
int
what_kind(buf, why)
    struct resp_buf *buf;
    char *why;
{
    u_int32 smask;
    int retval;
    int hops = buf->len;
    struct tr_resp *r = buf->resps + hops - 1;
    u_int32 next = r->tr_rmtaddr;

    retval = send_recv(next, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2, 1, &incr[0], NULL);
    print_host(next);
    if (retval) {
	u_int32 version = ntohl(incr[0].igmp.igmp_group.s_addr);
	u_int32 *p = (u_int32 *)incr[0].ndata;
	u_int32 *ep = p + (incr[0].len >> 2);
	char *type = "version ";

	retval = 0;
	switch (version & 0xFF) {
	  case 1:
	    type = "proteon/mrouted ";
	    retval = 1;
	    break;

	  case 10:
	  case 11:
	    type = "cisco ";
	}
	printf(" [%s%d.%d] %s\n",
	       type, version & 0xFF, (version >> 8) & 0xFF,
	       why);
	VAL_TO_MASK(smask, r->tr_smask);
	while (p < ep) {
	    u_int32 laddr = *p++;
	    int flags = (ntohl(*p) & 0xFF00) >> 8;
	    int n = ntohl(*p++) & 0xFF;
	    if (!(flags & (DVMRP_NF_DOWN | DVMRP_NF_DISABLED)) &&
		 (laddr & smask) == (qsrc & smask)) {
		printf("%3d  ", -(hops+2));
		print_host(qsrc);
		printf("\n");
		return 1;
	    }
	    p += n;
	}
	return retval;
    }
    printf(" %s\n", why);
    return 0;
}


char *
scale(hop)
    int *hop;
{
    if (*hop > -1000 && *hop < 10000) return (" ms");
    *hop /= 1000;
    if (*hop > -1000 && *hop < 10000) return (" s ");
    return ("s ");
}

/*
 * Calculate and print one line of packet loss and packet rate statistics.
 * Checks for count of all ones from mrouted 2.3 that doesn't have counters.
 */
#define NEITHER 0
#define INS     1
#define OUTS    2
#define BOTH    3
void
stat_line(r, s, have_next, rst)
    struct tr_resp *r, *s;
    int have_next;
    int *rst;
{
    int timediff = (ntohl(s->tr_qarr) - ntohl(r->tr_qarr)) >> 16;
    int v_lost, v_pct;
    int g_lost, g_pct;
    int v_out = ntohl(s->tr_vifout) - ntohl(r->tr_vifout);
    int g_out = ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt);
    int v_pps, g_pps;
    char v_str[8], g_str[8];
    int vhave = NEITHER;
    int ghave = NEITHER;
    int gmissing = NEITHER;
    char whochar;
    int badtime = 0;

    if (timediff == 0) {
	badtime = 1;
	/* Might be 32 bits of int seconds instead of 16int+16frac */
	timediff = ntohl(s->tr_qarr) - ntohl(r->tr_qarr);
	if (timediff == 0 || abs(timediff - statint) > statint)
	    timediff = 1;
    }
    v_pps = v_out / timediff;
    g_pps = g_out / timediff;

#define STATS_MISSING(x)	((x) == 0xFFFFFFFF)

    if (!STATS_MISSING(s->tr_vifout) && !STATS_MISSING(r->tr_vifout))
	    vhave |= OUTS;
    if (STATS_MISSING(s->tr_pktcnt) || STATS_MISSING(r->tr_pktcnt))
	    gmissing |= OUTS;
    if (!(*rst & BUG_NOPRINT))
	    ghave |= OUTS;

    if (have_next) {
	--r,  --s,  --rst;
	if (!STATS_MISSING(s->tr_vifin) && !STATS_MISSING(r->tr_vifin))
	    vhave |= INS;
	if (STATS_MISSING(s->tr_pktcnt) || STATS_MISSING(r->tr_pktcnt))
	    gmissing |= INS;
	if (!(*rst & BUG_NOPRINT))
	    ghave |= INS;
    }

    /*
     * Stats can be missing for any number of reasons:
     * - The hop may not be capable of collecting stats
     * - Traffic may be getting dropped at the previous hop
     *   and so this hop may not have any state
     *
     * We need a stronger heuristic to tell between these
     * two cases; in case 1 we don't want to print the stats
     * and in case 2 we want to print 100% loss.  We used to
     * err on the side of not printing, which is less useful
     * than printing 100% loss and dealing with it.
     */
#if 0
    /*
     * If both hops report as missing, then it's likely that there's just
     * no traffic flowing.
     *
     * If just one hop is missing, then we really don't have it.
     */
    if (gmissing != BOTH)
	ghave &= ~gmissing;
#endif

    whochar = have_next ? '^' : ' ';
    switch (vhave) {
      case BOTH:
	v_lost = v_out - (ntohl(s->tr_vifin) - ntohl(r->tr_vifin));
	if (v_out) v_pct = v_lost * 100 / v_out;
	else v_pct = 0;
	if (-20 < v_pct && v_pct < 101 && v_out > 10)
	  sprintf(v_str, "%3d%%", v_pct);
	else if (v_pct < -900 && v_out > 10)
	  sprintf(v_str, "%3dx", (int)(-v_pct / 100. + 1.));
	else if (v_pct <= -20 && v_out > 10)
	  sprintf(v_str, "%1.1fx", -v_pct / 100. + 1.);
	else
	  memcpy(v_str, " -- ", 5);

	if (tunstats)
	    printf("%6d/%-5d=%s", v_lost, v_out, v_str);
	else
	    printf("   ");
	printf("%4d pps", v_pps);
	if (v_pps && badtime)
	    printf("?");

	break;

      case INS:
	v_out = ntohl(s->tr_vifin) - ntohl(r->tr_vifin);
	v_pps = v_out / timediff;
	whochar = 'v';
	/* FALLTHROUGH */

      case OUTS:
	if (tunstats)
	    printf("      %c%-5d     ", whochar, v_out);
	else
	    printf("  %c", whochar);
	printf("%4d pps", v_pps);
	if (v_pps && badtime)
	    printf("?");

	break;

      case NEITHER:
	if (ghave != NEITHER)
	    if (tunstats)
		printf("                         ");
	    else
		printf("           ");

	break;
    }

    whochar = have_next ? '^' : ' ';
    switch (ghave) {
      case BOTH:
	g_lost = g_out - (ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt));
	if (g_out) g_pct = g_lost * 100 / g_out;
	else g_pct = 0;
	if (-20 < g_pct && g_pct < 101 && g_out > 10)
	  sprintf(g_str, "%3d%%", g_pct);
	else if (g_pct < -900 && g_out > 10)
	  sprintf(g_str, "%3dx", (int)(-g_pct / 100. + 1.));
	else if (g_pct <= -20 && g_out > 10)
	  sprintf(g_str, "%1.1fx", -g_pct / 100. + 1.);
	else
	  memcpy(g_str, " -- ", 5);

	printf("%s%6d/%-5d=%s%4d pps",
	       tunstats ? "" : "   ", g_lost, g_out, g_str, g_pps);
	if (g_pps && badtime)
	    printf("?");
	printf("\n");
	break;

#if 0
      case INS:
	g_out = ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt);
	g_pps = g_out / timediff;
	whochar = 'v';
	/* FALLTHROUGH */
#endif

      case OUTS:
	printf("%s     ?/%-5d     %4d pps",
	       tunstats ? "" : "   ", g_out, g_pps);
	if (badtime)
	    printf("?");
	printf("\n");
	break;

      case INS:
      case NEITHER:
	printf("\n");
	break;
    }


    if (debug > 2) {
	printf("\t\t\t\tv_in: %ld ", (long)ntohl(s->tr_vifin));
	printf("v_out: %ld ", (long)ntohl(s->tr_vifout));
	printf("pkts: %ld\n", (long)ntohl(s->tr_pktcnt));
	printf("\t\t\t\tv_in: %ld ", (long)ntohl(r->tr_vifin));
	printf("v_out: %ld ", (long)ntohl(r->tr_vifout));
	printf("pkts: %ld\n", (long)ntohl(r->tr_pktcnt));
	printf("\t\t\t\tv_in: %ld ",
	    (long)(ntohl(s->tr_vifin) - ntohl(r->tr_vifin)));
	printf("v_out: %ld ",
	    (long)(ntohl(s->tr_vifout) - ntohl(r->tr_vifout)));
	printf("pkts: %ld ", (long)(ntohl(s->tr_pktcnt) - ntohl(r->tr_pktcnt)));
	printf("time: %d\n", timediff);
	printf("\t\t\t\treset: %x hoptime: %lx\n", *rst, ntohl(s->tr_qarr));
    }
}

/*
 * A fixup to check if any pktcnt has been reset, and to fix the
 * byteorder bugs in mrouted 3.6 on little-endian machines.
 *
 * XXX Since periodic traffic sources are likely to have their
 *     pktcnt periodically reset, should we save old values when
 *     the reset occurs to keep slightly better statistics over
 *     the long term?  (e.g. SAP)
 */
void
fixup_stats(base, prev, new, bugs)
    struct resp_buf *base, *prev, *new;
    int *bugs;
{
    int rno = base->len;
    struct tr_resp *b = base->resps + rno;
    struct tr_resp *p = prev->resps + rno;
    struct tr_resp *n = new->resps + rno;
    int *r = bugs + rno;
    int res;
    int cleanup = 0;

    /* Check for byte-swappers.  Only check on the first trace,
     * since long-running traces can wrap around and falsely trigger. */
    while (--rno >= 0) {
#ifdef TEST_ONLY
	u_int32 nvifout = ntohl(n->tr_vifout);
	u_int32 pvifout = ntohl(p->tr_vifout);
#endif
	--n; --p; --b;
#ifdef TEST_ONLY	/*XXX this is still buggy, so disable it for release */
	if ((*r & BUG_SWAP) ||
	    ((base == prev) &&
	     (nvifout - pvifout) > (byteswap(nvifout) - byteswap(pvifout)))) {
	    if (1 || debug > 2) {
		printf("ip %s swaps; b %08x p %08x n %08x\n",
			inet_fmt(n->tr_inaddr, s1),
			ntohl(b->tr_vifout), pvifout, nvifout);
	    }
	    /* This host sends byteswapped reports; swap 'em */
	    if (!(*r & BUG_SWAP)) {
		*r |= BUG_SWAP;
		b->tr_qarr = byteswap(b->tr_qarr);
		b->tr_vifin = byteswap(b->tr_vifin);
		b->tr_vifout = byteswap(b->tr_vifout);
		b->tr_pktcnt = byteswap(b->tr_pktcnt);
	    }

	    n->tr_qarr = byteswap(n->tr_qarr);
	    n->tr_vifin = byteswap(n->tr_vifin);
	    n->tr_vifout = byteswap(n->tr_vifout);
	    n->tr_pktcnt = byteswap(n->tr_pktcnt);
	}
#endif
	/*
	 * A missing parenthesis in mrouted 3.5-3.8's prune.c
	 * causes extremely bogus time diff's.
	 * One half of the time calculation was
	 * inside an htonl() and one half wasn't.  Therefore, on
	 * a little-endian machine, both halves of the calculation
	 * would get added together in the little end.  Thus, the
	 * low-order 2 bytes are either 0000 (no overflow) or
	 * 0100 (overflow from the addition).
	 *
	 * Odds are against these particular bit patterns
	 * happening in both prev and new for actual time values.
	 */
	if ((*r & BUG_BOGUSTIME) || (((ntohl(n->tr_qarr) & 0xfeff) == 0x0000) &&
	    ((ntohl(p->tr_qarr) & 0xfeff) == 0x0000))) {
	    *r |= BUG_BOGUSTIME;
	    n->tr_qarr = new->rtime;
	    p->tr_qarr = prev->rtime;
	    b->tr_qarr = base->rtime;
	}
    }

    rno = base->len;
    b = base->resps + rno;
    p = prev->resps + rno;
    n = new->resps + rno;
    r = bugs + rno;

    while (--rno >= 0) {
	--n; --p; --b; --r;
	/*
	 * This hop has reset if:
	 * - There were statistics in the base AND previous pass, AND
	 *   - There are less packets this time than the first time and
	 *     we didn't reset last time, OR
	 *   - There are less packets this time than last time, OR
	 *   - There are no statistics on this pass.
	 *
	 * The "and we didn't reset last time" is necessary in the
	 * first branch of the OR because if the base is large and
	 * we reset last time but the constant-resetter-avoidance
	 * code kicked in so we delayed the copy of prev to base,
	 * new could still be below base so we trigger the
	 * constant-resetter code even though it was really only
	 * a single reset.
	 */
	res = ((b->tr_pktcnt != 0xFFFFFFFF) && (p->tr_pktcnt != 0xFFFFFFFF) &&
	       ((!(*r & BUG_RESET) && ntohl(n->tr_pktcnt) < ntohl(b->tr_pktcnt)) ||
	        (ntohl(n->tr_pktcnt) < ntohl(p->tr_pktcnt)) ||
		(n->tr_pktcnt == 0xFFFFFFFF)));
	if (debug > 2) {
    	    printf("\t\tip=%s, r=%d, res=%d\n", inet_fmt(b->tr_inaddr, s1), *r, res);
	    if (res)
		printf("\t\tbase=%ld, prev=%ld, new=%ld\n", ntohl(b->tr_pktcnt),
			    ntohl(p->tr_pktcnt), ntohl(n->tr_pktcnt));
	}
	if (*r & BUG_RESET) {
	    if (res || (*r & BUG_RESET2X)) {
		/*
		 * This router appears to be a 3.4 with that nasty ol'
		 * neighbor version bug, which causes it to constantly
		 * reset.  Just nuke the statistics for this node, and
		 * don't even bother giving it the benefit of the
		 * doubt from now on.
		 */
		p->tr_pktcnt = b->tr_pktcnt = n->tr_pktcnt;
		*r |= BUG_RESET2X;
	    } else {
		/*
		 * This is simply the situation that the original
		 * fixup_stats was meant to deal with -- that a
		 * 3.3 or 3.4 router deleted a cache entry while
		 * traffic was still active.
		 */
		*r &= ~BUG_RESET;
		cleanup = 1;
	    }
	} else
	    if (res)
		*r |= BUG_RESET;
    }

    if (cleanup == 0) return;

    /*
     * If some hop reset its counters and didn't continue to
     * reset, then we pretend that the previous
     * trace was the first one.
     */
    rno = base->len;
    b = base->resps + rno;
    p = prev->resps + rno;

    while (--rno >= 0) (--b)->tr_pktcnt = (--p)->tr_pktcnt;
    base->qtime = prev->qtime;
    base->rtime = prev->rtime;
}

/*
 * Check per-source losses along path and compare with threshold.
 */
int
check_thresh(thresh, base, prev, new)
    int thresh;
    struct resp_buf *base, *prev, *new;
{
    int rno = base->len - 1;
    struct tr_resp *b = base->resps + rno;
    struct tr_resp *p = prev->resps + rno;
    struct tr_resp *n = new->resps + rno;
    int g_out, g_lost;

    while (TRUE) {
	if ((n->tr_inaddr != b->tr_inaddr) ||
	    (n->tr_outaddr != b->tr_outaddr) ||
	    (n->tr_rmtaddr != b->tr_rmtaddr))
	  return 1;		/* Route changed */

	if (rno-- < 1) break;
    	g_out = ntohl(n->tr_pktcnt) - ntohl(p->tr_pktcnt);
	b--; n--; p--;
	g_lost = g_out - (ntohl(n->tr_pktcnt) - ntohl(p->tr_pktcnt));
	if (g_out && ((g_lost * 100 + (g_out >> 1))/ g_out) > thresh) {
	    return TRUE;
	}
    }
    return FALSE;
}

/*
 * Print responses with statistics for forward path (from src to dst)
 */
int
print_stats(base, prev, new, bugs, names)
    struct resp_buf *base, *prev, *new;
    int *bugs;
    char **names;
{
    int rtt, hop;
    char *ms;
    u_int32 smask;
    int rno = base->len - 1;
    struct tr_resp *b = base->resps + rno;
    struct tr_resp *p = prev->resps + rno;
    struct tr_resp *n = new->resps + rno;
    int *r = bugs + rno;
    u_long resptime = new->rtime;
    u_long qarrtime = ntohl(n->tr_qarr);
    u_int ttl = MaX(1, n->tr_fttl) + 1;
    int first = (base == prev);

    VAL_TO_MASK(smask, b->tr_smask);
    printf("  Source        Response Dest    ");
    if (tunstats)
	printf("Packet Statistics For     Only For Traffic\n");
    else
	printf("Overall     Packet Statistics For Traffic From\n");
    (void)inet_fmt(base->qhdr.tr_src, s1);
    printf("%-15s %-15s  ",
	   ((b->tr_inaddr & smask) == (base->qhdr.tr_src & smask)) ?
		s1 : "   * * *       ",
	   inet_fmt(base->qhdr.tr_raddr, s2));
    (void)inet_fmt(base->igmp.igmp_group.s_addr, s2);
    if (tunstats)
	printf("All Multicast Traffic     From %s\n", s1);
    else
	printf("Packet      %s To %s\n", s1, s2);
    rtt = t_diff(resptime, new->qtime);
    ms = scale(&rtt);
    printf("     %c       __/  rtt%5d%s    ",
	   (first && !verbose) ? 'v' : '|', rtt, ms);
    if (tunstats)
	printf("Lost/Sent = Pct  Rate       To %s\n", s2);
    else
	printf(" Rate       Lost/Sent = Pct  Rate\n");
    if (!first || verbose) {
	hop = t_diff(resptime, qarrtime);
	ms = scale(&hop);
	printf("     v      /     hop%5d%s    ", hop, ms);
	if (tunstats)
	    printf("---------------------     --------------------\n");
	else
	    printf("-------     ---------------------\n");
    }
    if ((b->tr_inaddr & smask) != (base->qhdr.tr_src & smask) &&
	    b->tr_rmtaddr != 0) {
	printf("%-15s %-14s is the previous hop\n", inet_fmt(b->tr_rmtaddr, s1),
		inet_name(b->tr_rmtaddr));
	printf("     v     ^\n");
    }
    if (debug > 2) {
	printf("\t\t\t\tv_in: %ld ", (long)ntohl(n->tr_vifin));
	printf("v_out: %ld ", (long)ntohl(n->tr_vifout));
	printf("pkts: %ld\n", (long)ntohl(n->tr_pktcnt));
	printf("\t\t\t\tv_in: %ld ", (long)ntohl(b->tr_vifin));
	printf("v_out: %ld ", (long)ntohl(b->tr_vifout));
	printf("pkts: %ld\n", (long)ntohl(b->tr_pktcnt));
	printf("\t\t\t\tv_in: %ld ",
	    (long)(ntohl(n->tr_vifin) - ntohl(b->tr_vifin)));
	printf("v_out: %ld ",
	    (long)(ntohl(n->tr_vifout) - ntohl(b->tr_vifout)));
	printf("pkts: %ld\n",
	    (long)(ntohl(n->tr_pktcnt) - ntohl(b->tr_pktcnt)));
	printf("\t\t\t\treset: %x hoptime: %lx\n", *r, (long)ntohl(n->tr_qarr));
    }

    while (TRUE) {
	if ((n->tr_inaddr != b->tr_inaddr) ||
	    (n->tr_outaddr != b->tr_outaddr) ||
	    (n->tr_rmtaddr != b->tr_rmtaddr))
	  return 1;		/* Route changed */

	if ((n->tr_inaddr != n->tr_outaddr) && n->tr_inaddr)
	  printf("%-15s\n", inet_fmt(n->tr_inaddr, s1));
	printf("%-15s %-14s %s%s\n", inet_fmt(n->tr_outaddr, s1), names[rno],
		 flag_type(n->tr_rflags),
		 (*r & BUG_NOPRINT) ? " [reset counters]" : "");

	if (rno-- < 1) break;

	printf("     %c     ^      ttl%5d   ", (first && !verbose) ? 'v' : '|',
								ttl);
	stat_line(p, n, TRUE, r);
	if (!first || verbose) {
	    resptime = qarrtime;
	    qarrtime = ntohl((n-1)->tr_qarr);
	    hop = t_diff(resptime, qarrtime);
	    ms = scale(&hop);
	    printf("     v     |      hop%5d%s", hop, ms);
	    if (first)
		printf("\n");
	    else
		stat_line(b, n, TRUE, r);
	}

	--b, --p, --n, --r;
	ttl = MaX(ttl, MaX(1, n->tr_fttl) + base->len - rno);
    }
	   
    printf("     %c      \\__   ttl%5d   ", (first && !verbose) ? 'v' : '|',
							ttl);
    stat_line(p, n, FALSE, r);
    if (!first || verbose) {
	hop = t_diff(qarrtime, new->qtime);
	ms = scale(&hop);
	printf("     v         \\  hop%5d%s", hop, ms);
	if (first)
	    printf("\n");
	else
	    stat_line(b, n, FALSE, r);
    }
    printf("%-15s %s\n", inet_fmt(base->qhdr.tr_dst, s1),
			!passive ? inet_fmt(lcl_addr, s2) : "   * * *       ");
    printf("  Receiver      Query Source\n\n");
    return 0;
}

/*
 * Determine whether or not the path has changed.
 */
int
path_changed(base, new)
    struct resp_buf *base, *new;
{
    int rno = base->len - 1;
    struct tr_resp *b = base->resps + rno;
    struct tr_resp *n = new->resps + rno;

    while (rno-- >= 0) {
	if ((n->tr_inaddr != b->tr_inaddr) ||
	    (n->tr_outaddr != b->tr_outaddr) ||
	    (n->tr_rmtaddr != b->tr_rmtaddr))
	  return 1;		/* Route changed */
	if ((b->tr_rflags == TR_NO_RTE) &&
	    (n->tr_rflags != TR_NO_RTE))
	  return 1;		/* Route got longer? */
	--n;
	--b;
    }
    return 0;
}


/***************************************************************************
 *	main
 ***************************************************************************/

int
main(argc, argv)
int argc;
char *argv[];
{
    int udp;
    struct sockaddr_in addr;
    int addrlen = sizeof(addr);
    int recvlen;
    struct timeval tv;
    struct resp_buf *prev, *new;
    struct tr_resp *r;
    u_int32 smask;
    int rno;
    int hops, nexthop, tries;
    u_int32 lastout = 0;
    int numstats = 1;
    int waittime;
    int seed;
    int hopbyhop;
    int i;
    int printed = 1;

    if (geteuid() != 0)
	errx(1, "must be root");

    /*
     * We might get spawned by vat with the audio device open.
     * Close everything but stdin, stdout, stderr.
     */
    for (i = 3; i < 255; i++)
	close(i);

    init_igmp();
    setuid(getuid());

    argv++, argc--;
    if (argc == 0) usage();

    while (argc > 0 && *argv[0] == '-') {
	char *p = *argv++;  argc--;
	p++;
	do {
	    char c = *p++;
	    char *arg = (char *) 0;
	    if (isdigit(*p)) {
		arg = p;
		p = "";
	    } else if (argc > 0) arg = argv[0];
	    switch (c) {
	      case 'd':			/* Unlisted debug print option */
		if (arg && isdigit(*arg)) {
		    debug = atoi(arg);
		    if (debug < 0) debug = 0;
		    if (debug > 3) debug = 3;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 'M':			/* Use multicast for reponse */
		multicast = TRUE;
		break;
	      case 'U':			/* Use unicast for response */
		unicast = TRUE;
		break;
	      case 'L':			/* Trace w/ loss threshold */
		if (arg && isdigit(*arg)) {
		    lossthresh = atoi(arg);
		    if (lossthresh < 0)
			lossthresh = 0;
		    numstats = 3153600;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
		break;
	      case 'O':			/* Don't use IP options */
		sendopts = FALSE;
		break;
	      case 'P':			/* Just watch the path */
		printstats = FALSE;
		numstats = 3153600;
		break;
	      case 'Q':			/* (undoc.) always use this QID */
		if (arg && isdigit(*arg)) {
		    staticqid = atoi(arg);
		    if (staticqid < 0)
			staticqid = 0;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
		break;
	      case 'T':			/* Print confusing tunnel stats */
		tunstats = TRUE;
		break;
	      case 'W':			/* Cisco's "weak" mtrace */
		weak = TRUE;
		break;
	      case 'V':			/* Print version and exit */
		/*
		 * FreeBSD wants to have its own Id string, so
		 * determination of the version number has to change.
		 * XXX Note that this must be changed by hand on importing
		 * XXX new versions!
		 */
		{
		    char *r = strdup(rcsid);
		    char *s = strchr(r, ',');

		    while (s && *(s+1) != 'v')
			s = strchr(s + 1, ',');

		    if (s) {
			char *q;

			s += 3;		/* , v sp */
			q = strchr(s, ' ');
			if (q)
				*q = '\0';
			fprintf(stderr, "mtrace version 5.2/%s\n", s);
		    } else {
			fprintf(stderr, "mtrace could not determine version number!?\n");
		    }
		    exit(1);
		}
		break;
	      case 'l':			/* Loop updating stats indefinitely */
		numstats = 3153600;
		break;
	      case 'n':			/* Don't reverse map host addresses */
		numeric = TRUE;
		break;
	      case 'p':			/* Passive listen for traces */
		passive = TRUE;
		break;
	      case 'v':			/* Verbosity */
		verbose = TRUE;
		break;
	      case 's':			/* Short form, don't wait for stats */
		numstats = 0;
		break;
	      case 'w':			/* Time to wait for packet arrival */
		if (arg && isdigit(*arg)) {
		    timeout = atoi(arg);
		    if (timeout < 1) timeout = 1;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 'f':			/* first hop */
		if (arg && isdigit(*arg)) {
		    qno = atoi(arg);
		    if (qno > MAXHOPS) qno = MAXHOPS;
		    else if (qno < 1) qno = 0;
		    if (arg == argv[0]) argv++, argc--;
		    fflag++;
		    break;
		} else
		    usage();
	      case 'm':			/* Max number of hops to trace */
		if (arg && isdigit(*arg)) {
		    qno = atoi(arg);
		    if (qno > MAXHOPS) qno = MAXHOPS;
		    else if (qno < 1) qno = 0;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 'q':			/* Number of query retries */
		if (arg && isdigit(*arg)) {
		    nqueries = atoi(arg);
		    if (nqueries < 1) nqueries = 1;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 'g':			/* Last-hop gateway (dest of query) */
		if (arg && (gwy = host_addr(arg))) {
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 't':			/* TTL for query packet */
		if (arg && isdigit(*arg)) {
		    qttl = atoi(arg);
		    if (qttl < 1) qttl = 1;
		    rttl = qttl;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 'e':			/* Extra hops past non-responder */
		if (arg && isdigit(*arg)) {
		    extrahops = atoi(arg);
		    if (extrahops < 0) extrahops = 0;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 'r':			/* Dest for response packet */
		if (arg && (raddr = host_addr(arg))) {
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 'i':			/* Local interface address */
		if (arg && (lcl_addr = host_addr(arg))) {
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      case 'S':			/* Stat accumulation interval */
		if (arg && isdigit(*arg)) {
		    statint = atoi(arg);
		    if (statint < 1) statint = 1;
		    if (arg == argv[0]) argv++, argc--;
		    break;
		} else
		    usage();
	      default:
		usage();
	    }
	} while (*p);
    }

    if (argc > 0 && (qsrc = host_addr(argv[0]))) {          /* Source of path */
	if (IN_MULTICAST(ntohl(qsrc))) {
	    if (gwy) {
		/* Should probably rewrite arg parsing at some point, as
		 * this makes "mtrace -g foo 224.1.2.3 224.2.3.4" valid!... */
		qgrp = qsrc;
		qsrc = 0;
	    } else {
		usage();
	    }
	}
	argv++, argc--;
	if (argc > 0 && (qdst = host_addr(argv[0]))) {      /* Dest of path */
	    argv++, argc--;
	    if (argc > 0 && (qgrp = host_addr(argv[0]))) {  /* Path via group */
		argv++, argc--;
	    }
	    if (IN_MULTICAST(ntohl(qdst))) {
		u_int32 temp = qdst;
		qdst = qgrp;
		qgrp = temp;
		if (IN_MULTICAST(ntohl(qdst))) usage();
	    } else if (qgrp && !IN_MULTICAST(ntohl(qgrp))) usage();
	}
    }

    if (passive) {
	passive_mode();
	return(0);
    }

    if (argc > 0) {
	usage();
    }

#ifdef SUNOS5
    if (sendopts)
	checkforsolarisbug();
#endif

    /*
     * Set useful defaults for as many parameters as possible.
     */

    defgrp = 0;				/* Default to no group */
    query_cast = htonl(0xE0000002);	/* All routers multicast addr */
    resp_cast = htonl(0xE0000120);	/* Mtrace response multicast addr */
    if (qgrp == 0) {
	if (!weak)
	    qgrp = defgrp;
	if (printstats && numstats != 0 && !tunstats) {
	    /* Stats are useless without a group */
	    warnx(
	"WARNING: no multicast group specified, so no statistics printed");
	    numstats = 0;
	}
    } else {
	if (weak)
	    warnx(
	"WARNING: group was specified so not performing \"weak\" mtrace");
    }

    /*
     * Get default local address for multicasts to use in setting defaults.
     */
    addr.sin_family = AF_INET;
#if (defined(BSD) && (BSD >= 199103))
    addr.sin_len = sizeof(addr);
#endif
    addr.sin_addr.s_addr = qgrp ? qgrp : query_cast;
    addr.sin_port = htons(2000);	/* Any port above 1024 will do */

    /*
     * Note that getsockname() can return 0 on some systems
     * (notably SunOS 5.x, x < 6).  This is taken care of in
     * get_netmask().  If the default multicast interface (set
     * with the route for 224.0.0.0) is not the same as the
     * hostname, mtrace -i [if_addr] will have to be used.
     */
    if (((udp = socket(AF_INET, SOCK_DGRAM, 0)) < 0) ||
	(connect(udp, (struct sockaddr *) &addr, sizeof(addr)) < 0) ||
	getsockname(udp, (struct sockaddr *) &addr, &addrlen) < 0)
	err(-1, "determining local address");

#ifdef SUNOS5
    /*
     * SunOS 5.X prior to SunOS 2.6, getsockname returns 0 for udp socket.
     * This call to sysinfo will return the hostname.
     * If the default multicast interfface (set with the route
     * for 224.0.0.0) is not the same as the hostname,
     * mtrace -i [if_addr] will have to be used.
     */
    if (addr.sin_addr.s_addr == 0) {
	char myhostname[MAXHOSTNAMELEN];
	struct hostent *hp;
	int error;
    
	error = sysinfo(SI_HOSTNAME, myhostname, sizeof(myhostname));
	if (error == -1)
	    err(1, "getting my hostname");

	hp = gethostbyname(myhostname);
	if (hp == NULL || hp->h_addrtype != AF_INET ||
	    hp->h_length != sizeof(addr.sin_addr))
	    err(1, "finding IP address for my hostname");

	memcpy((char *)&addr.sin_addr.s_addr, hp->h_addr, hp->h_length);
    }
#endif

    /*
     * Default destination for path to be queried is the local host.
     * When gateway specified, default destination is that gateway
     *  and default source is local host.
     */
    if (qdst == 0) {
	qdst = lcl_addr ? lcl_addr : addr.sin_addr.s_addr;
	dst_netmask = get_netmask(udp, &qdst);
	if (gwy && (gwy & dst_netmask) != (qdst & dst_netmask) &&
		!IN_MULTICAST(ntohl(gwy)))
	    qdst = gwy;
    }
    if (qsrc == 0 && gwy)
	qsrc = lcl_addr ? lcl_addr : addr.sin_addr.s_addr;
    if (qsrc == 0)
	usage();
    if (!dst_netmask)
	dst_netmask = get_netmask(udp, &qdst);
    close(udp);
    if (lcl_addr == 0) lcl_addr = addr.sin_addr.s_addr;

    /*
     * Initialize the seed for random query identifiers.
     */
    gettimeofday(&tv, 0);
    seed = tv.tv_usec ^ lcl_addr;
#ifdef SYSV    
    srand48(seed);
#endif

    /*
     * Protect against unicast queries to mrouted versions that might crash.
     * Also use the obsolete "can mtrace" neighbor bit to warn about
     * older implementations.
     */
    if (gwy && !IN_MULTICAST(ntohl(gwy)))
      if (send_recv(gwy, IGMP_DVMRP, DVMRP_ASK_NEIGHBORS2, 1, &incr[0], NULL)) {
	int flags = ntohl(incr[0].igmp.igmp_group.s_addr);
	int version = flags & 0xFFFF;
	int info = (flags & 0xFF0000) >> 16;

	if (version == 0x0303 || version == 0x0503) {
	    printf("Don't use -g to address an mrouted 3.%d, it might crash\n",
		   (version >> 8) & 0xFF);
	    exit(0);
	}
	if ((info & 0x08) == 0) {
	    printf("mtrace: ");
	    print_host(gwy);
	    printf(" probably doesn't support mtrace, trying anyway...\n");
	}
      }

    printf("Mtrace from %s to %s via group %s\n",
	   inet_fmt(qsrc, s1), inet_fmt(qdst, s2), inet_fmt(qgrp, s3));

    if ((qdst & dst_netmask) == (qsrc & dst_netmask))
	fprintf(stderr, "mtrace: Source & receiver appear to be directly connected\n");

    /*
     * If the response is to be a multicast address, make sure we 
     * are listening on that multicast address.
     */
    if (raddr) {
	if (IN_MULTICAST(ntohl(raddr))) k_join(raddr, lcl_addr);
    } else k_join(resp_cast, lcl_addr);

    memset(&base, 0, sizeof(base));

    /*
     * If the destination is on the local net, the last-hop router can
     * be found by multicast to the all-routers multicast group.
     * Otherwise, use the group address that is the subject of the
     * query since by definition the last-hop router will be a member.
     * Set default TTLs for local remote multicasts.
     */
    if (gwy == 0)
      if ((qdst & dst_netmask) == (lcl_addr & dst_netmask)) tdst = query_cast;
      else tdst = qgrp;
    else tdst = gwy;
    if (tdst == 0 && qgrp == 0)
	errx(1, "mtrace: weak mtrace requires -g if destination is not local.\n");

    if (IN_MULTICAST(ntohl(tdst))) {
      k_set_loop(1);	/* If I am running on a router, I need to hear this */
      if (tdst == query_cast) k_set_ttl(qttl ? qttl : 1);
      else k_set_ttl(qttl ? qttl : MULTICAST_TTL1);
    }

    /*
     * Try a query at the requested number of hops or MAXHOPS if unspecified.
     */
    if (qno == 0) {
	hops = MAXHOPS;
	tries = 1;
	printf("Querying full reverse path... ");
	fflush(stdout);
    } else {
	hops = qno;
	tries = nqueries;
	if (fflag)
	    printf("Querying full reverse path, starting at hop %d...", qno);
	else
	    printf("Querying reverse path, maximum %d hops... ", qno);
	fflush(stdout); 
    }
    base.rtime = 0;
    base.len = 0;
    hopbyhop = FALSE;

    recvlen = send_recv(tdst, IGMP_MTRACE, hops, tries, &base, mtrace_callback);

    /*
     * If the initial query was successful, print it.  Otherwise, if
     * the query max hop count is the default of zero, loop starting
     * from one until there is no response for extrahops more hops.  The
     * extra hops allow getting past an mtrace-capable mrouter that can't
     * send multicast packets because all phyints are disabled.
     */
    if (recvlen) {
	printf("\n  0  ");
	print_host(qdst);
	printf("\n");
	print_trace(1, &base, names);
	r = base.resps + base.len - 1;
	if (r->tr_rflags == TR_OLD_ROUTER || r->tr_rflags == TR_NO_SPACE ||
		(qno != 0 && r->tr_rmtaddr != 0 && !fflag)) {
	    printf("%3d  ", -(base.len+1));
	    what_kind(&base, r->tr_rflags == TR_OLD_ROUTER ?
				   "doesn't support mtrace"
				 : "is the next hop");
	} else {
	    if (fflag) {
		nexthop = hops = qno;
		goto continuehop;
	    }
	    VAL_TO_MASK(smask, r->tr_smask);
	    if ((r->tr_inaddr & smask) == (qsrc & smask)) {
		printf("%3d  ", -(base.len+1));
		print_host(qsrc);
		printf("\n");
	    }
	}
    } else if (qno == 0) {
	hopbyhop = TRUE;
	printf("switching to hop-by-hop:\n  0  ");
	print_host(qdst);
	printf("\n");

	for (hops = 1, nexthop = 1; hops <= MAXHOPS; ++hops) {
	    printf("%3d  ", -hops);
	    fflush(stdout);

	    /*
	     * After a successful first hop, try switching to the unicast
	     * address of the last-hop router instead of multicasting the
	     * trace query.  This should be safe for mrouted versions 3.3
	     * and 3.5 because there is a long route timeout with metric
	     * infinity before a route disappears.  Switching to unicast
	     * reduces the amount of multicast traffic and avoids a bug
	     * with duplicate suppression in mrouted 3.5.
	     */
	    if (hops == 2 && gwy == 0 && lastout != 0 &&
		(recvlen = send_recv(lastout, IGMP_MTRACE, hops, 1, &base, mtrace_callback)))
	      tdst = lastout;
	    else recvlen = send_recv(tdst, IGMP_MTRACE, hops, nqueries, &base, mtrace_callback);

	    if (recvlen == 0) {
		/*if (hops == 1) break;*/
		if (hops == nexthop) {
		    if (hops == 1) {
			printf("\n");
		    } else if (what_kind(&base, "didn't respond")) {
			/* the ask_neighbors determined that the
			 * not-responding router is the first-hop. */
			break;
		    }
		    if (extrahops == 0)
			break;
		} else if (hops < nexthop + extrahops) {
		    printf("\n");
		} else {
		    printf("...giving up\n");
		    break;
		}
		continue;
	    }
	    if (base.len == hops &&
		(hops == 1 || (base.resps+nexthop-2)->tr_outaddr == lastout)) {
	    	if (hops == nexthop) {
		    print_trace(-hops, &base, names);
		} else {
		    printf("\nResuming...\n");
		    print_trace(nexthop, &base, names);
		}
	    } else {
		if (base.len < hops) {
		    /*
		     * A shorter trace than requested means a fatal error
		     * occurred along the path, or that the route changed
		     * to a shorter one.
		     *
		     * If the trace is longer than the last one we received,
		     * then we are resuming from a skipped router (but there
		     * is still probably a problem).
		     *
		     * If the trace is shorter than the last one we
		     * received, then the route must have changed (and
		     * there is still probably a problem).
		     */
		    if (nexthop <= base.len) {
			printf("\nResuming...\n");
			print_trace(nexthop, &base, names);
		    } else if (nexthop > base.len + 1) {
			hops = base.len;
			printf("\nRoute must have changed...\n");
			print_trace(1, &base, names);
		    }
		} else {
		    /*
		     * The last hop address is not the same as it was.
		     * If we didn't know the last hop then we just
		     * got the first response from a hop-by-hop trace;
		     * if we did know the last hop then
		     * the route probably changed underneath us.
		     */
		    hops = base.len;
		    if (lastout != 0)
			printf("\nRoute must have changed...\n");
		    else
			printf("\nResuming...\n");
		    print_trace(1, &base, names);
		}
	    }
continuehop:
	    r = base.resps + base.len - 1;
	    lastout = r->tr_outaddr;

	    if (base.len < hops ||
		r->tr_rmtaddr == 0 ||
		(r->tr_rflags & 0x80)) {
		VAL_TO_MASK(smask, r->tr_smask);
		if (r->tr_rmtaddr) {
		    if (hops != nexthop) {
			printf("\n%3d  ", -(base.len+1));
		    }
		    what_kind(&base, r->tr_rflags == TR_OLD_ROUTER ?
				"doesn't support mtrace" :
				"would be the next hop");
		    /* XXX could do segmented trace if TR_NO_SPACE */
		} else if (r->tr_rflags == TR_NO_ERR &&
			   (r->tr_inaddr & smask) == (qsrc & smask)) {
		    printf("%3d  ", -(hops + 1));
		    print_host(qsrc);
		    printf("\n");
		}
		break;
	    }

	    nexthop = hops + 1;
	}
    }

    if (base.rtime == 0) {
	printf("Timed out receiving responses\n");
	if (IN_MULTICAST(ntohl(tdst)))
	  if (tdst == query_cast)
	    printf("Perhaps no local router has a route for source %s\n",
		   inet_fmt(qsrc, s1));
	  else
	    printf("Perhaps receiver %s is not a member of group %s,\n\
or no router local to it has a route for source %s,\n\
or multicast at ttl %d doesn't reach its last-hop router for that source\n",
		   inet_fmt(qdst, s2), inet_fmt(qgrp, s3), inet_fmt(qsrc, s1),
		   qttl ? qttl : MULTICAST_TTL1);
	exit(1);
    }

    printf("Round trip time %d ms; ", t_diff(base.rtime, base.qtime));
    {
	struct tr_resp *n = base.resps + base.len - 1;
	u_int ttl = n->tr_fttl + 1;

	rno = base.len - 1;
	while (--rno > 0) {
	    --n;
	    ttl = MaX(ttl, MaX(1, n->tr_fttl) + base.len - rno);
	}
	printf("total ttl of %d required.\n\n",ttl);
    }

    /*
     * Use the saved response which was the longest one received,
     * and make additional probes after delay to measure loss.
     */
    raddr = base.qhdr.tr_raddr;
    rttl = TR_GETTTL(base.qhdr.tr_rttlqid);
    gettimeofday(&tv, 0);
    waittime = statint - (((tv.tv_sec + JAN_1970) & 0xFFFF) - (base.qtime >> 16));
    prev = &base;
    new = &incr[numstats&1];

    /*
     * Zero out bug-avoidance counters
     */
    memset(bugs, 0, sizeof(bugs));

    if (!printstats)
	printf("Monitoring path..");

    while (numstats--) {
	if (waittime < 1) printf("\n");
	else {
	    if (printstats && (lossthresh == 0 || printed)) {
		printf("Waiting to accumulate statistics...");
	    } else {
		printf(".");
	    }
	    fflush(stdout);
	    sleep((unsigned)waittime);
	}
	printed = 0;
	rno = hopbyhop ? base.len : qno ? qno : MAXHOPS;
	recvlen = send_recv(tdst, IGMP_MTRACE, rno, nqueries, new, mtrace_callback);

	if (recvlen == 0) {
	    printf("Timed out.\n");
	    if (numstats) {
		numstats++;
		continue;
	    } else
		exit(1);
	}

	if (base.len != new->len || path_changed(&base, new)) {
	    printf("%s", base.len == new->len ? "Route changed" :
					"Trace length doesn't match");
	    if (!printstats)
		printf(" after %d seconds",
		   (int)((new->qtime - base.qtime) >> 16));
	    printf(":\n");
printandcontinue:
	    print_trace(1, new, names);
	    numstats++;
	    bcopy(new, &base, sizeof(base));
	    nexthop = hops = new->len;
	    printf("Continuing with hop-by-hop...\n");
	    goto continuehop;
	}

	if (printstats) {
	    if (new->igmp.igmp_group.s_addr != qgrp ||
		new->qhdr.tr_src != qsrc || new->qhdr.tr_dst != qdst)
		printf("\nWARNING: trace modified en route; statistics may be incorrect\n");
	    fixup_stats(&base, prev, new, bugs);
	    if ((lossthresh == 0) || check_thresh(lossthresh, &base, prev, new)) {
		printf("Results after %d seconds",
		       (int)((new->qtime - base.qtime) >> 16));
		if (lossthresh)
		    printf(" (this trace %d seconds)",
			   (int)((new->qtime - prev->qtime) >> 16));
		if (verbose) {
		    time_t t = time(0);
		    struct tm *qr = localtime(&t);

		    printf(" qid 0x%06x at %2d:%02d:%02d",
				TR_GETQID(base.qhdr.tr_rttlqid),
				qr->tm_hour, qr->tm_min, qr->tm_sec);
		}
		printf(":\n\n");
		printed = 1;
		if (print_stats(&base, prev, new, bugs, names)) {
		    printf("This should have been detected earlier, but ");
		    printf("Route changed:\n");
		    goto printandcontinue;
		}
	    }
	}
	prev = new;
	new = &incr[numstats&1];
	waittime = statint;
    }

    /*
     * If the response was multicast back, leave the group
     */
    if (raddr) {
	if (IN_MULTICAST(ntohl(raddr)))	k_leave(raddr, lcl_addr);
    } else k_leave(resp_cast, lcl_addr);

    return (0);
}

static void
usage()
{
	fprintf(stderr, "%s\n%s\n%s\n",
	"usage: mtrace [-MUOPTWVlnpvs] [-e extra_hops] [-f first_hop] [-i if_addr]",
	"              [-g gateway] [-m max_hops] [-q nqueries] [-r resp_dest]",
	"              [-S statint] [-t ttl] [-w wait] source [receiver] [group]");
	exit(1);
}

void
check_vif_state()
{
    log(LOG_WARNING, errno, "sendto");
}

/*
 * Log errors and other messages to stderr, according to the severity
 * of the message and the current debug level.  For errors of severity
 * LOG_ERR or worse, terminate the program.
 */
#ifdef __STDC__
void
log(int severity, int syserr, char *format, ...)
{
	va_list ap;
	char    fmt[100];

	va_start(ap, format);
#else
/*VARARGS3*/
void 
log(severity, syserr, format, va_alist)
	int     severity, syserr;
	char   *format;
	va_dcl
{
	va_list ap;
	char    fmt[100];

	va_start(ap);
#endif

    switch (debug) {
	case 0: if (severity > LOG_WARNING) return;
	case 1: if (severity > LOG_NOTICE) return;
	case 2: if (severity > LOG_INFO  ) return;
	default:
	    fmt[0] = '\0';
	    if (severity == LOG_WARNING) 
		strcpy(fmt, "warning - ");
	    strncat(fmt, format, sizeof(fmt)-strlen(fmt));
	    fmt[sizeof(fmt)-1]='\0';
	    vfprintf(stderr, fmt, ap);
	    if (syserr == 0)
		fprintf(stderr, "\n");
	    else if (syserr < sys_nerr)
		fprintf(stderr, ": %s\n", sys_errlist[syserr]);
	    else
		fprintf(stderr, ": errno %d\n", syserr);
    }
    if (severity <= LOG_ERR) exit(1);
}
OpenPOWER on IntegriCloud