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 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728
|
/*
* scamper_do_trace.c
*
* $Id: scamper_do_trace.c,v 1.135.2.15 2008/04/08 19:03:42 mjl Exp $
*
* Copyright (C) 2005-2008 The University of Waikato
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <sys/param.h>
#if !defined(__sun__)
#include <sys/sysctl.h>
#endif
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <net/if.h>
#if defined(__linux__)
#define __FAVOR_BSD
#else
#include <net/if_dl.h>
#endif
#if defined(__sun__)
#define BSD_COMP
#endif
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <netinet/udp.h>
#include <netinet/icmp6.h>
#include <netinet/tcp.h>
#if defined(__APPLE__)
#include <stdint.h>
#endif
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#if defined(DMALLOC)
#include <dmalloc.h>
#endif
#include "scamper.h"
#include "scamper_addr.h"
#include "scamper_list.h"
#include "scamper_tlv.h"
#include "scamper_trace.h"
#include "scamper_task.h"
#include "scamper_queue.h"
#include "scamper_icmp_resp.h"
#include "scamper_fds.h"
#include "scamper_dl.h"
#include "scamper_probe.h"
#include "scamper_rtsock.h"
#include "scamper_privsep.h"
#include "scamper_getsrc.h"
#include "scamper_file.h"
#include "scamper_outfiles.h"
#include "scamper_addresslist.h"
#include "scamper_debug.h"
#include "scamper_do_trace.h"
#include "scamper_addr2mac.h"
#include "scamper_options.h"
#include "scamper_icmp4.h"
#include "scamper_icmp6.h"
#include "scamper_tcp4.h"
#include "scamper_udp4.h"
#include "scamper_udp6.h"
#include "utils.h"
#define SCAMPER_DO_TRACE_ATTEMPTS_MIN 1
#define SCAMPER_DO_TRACE_ATTEMPTS_DEF 2
#define SCAMPER_DO_TRACE_ATTEMPTS_MAX 9
#define SCAMPER_DO_TRACE_DPORT_MIN 1
#define SCAMPER_DO_TRACE_DPORT_DEF (32768+777)
#define SCAMPER_DO_TRACE_DPORT_MAX 65535
#define SCAMPER_DO_TRACE_FIRSTHOP_MIN 1
#define SCAMPER_DO_TRACE_FIRSTHOP_DEF 1
#define SCAMPER_DO_TRACE_FIRSTHOP_MAX 255
#define SCAMPER_DO_TRACE_GAPLIMIT_MIN 1
#define SCAMPER_DO_TRACE_GAPLIMIT_DEF 5
#define SCAMPER_DO_TRACE_GAPLIMIT_MAX 255
#define SCAMPER_DO_TRACE_GAPACTION_MIN 1
#define SCAMPER_DO_TRACE_GAPACTION_DEF SCAMPER_TRACE_GAPACTION_STOP
#define SCAMPER_DO_TRACE_GAPACTION_MAX 2
#define SCAMPER_DO_TRACE_HOLDTIME_MIN 0
#define SCAMPER_DO_TRACE_HOLDTIME_DEF 0
#define SCAMPER_DO_TRACE_HOLDTIME_MAX 255
#define SCAMPER_DO_TRACE_HOPLIMIT_MIN 0
#define SCAMPER_DO_TRACE_HOPLIMIT_DEF 0
#define SCAMPER_DO_TRACE_HOPLIMIT_MAX 255
#define SCAMPER_DO_TRACE_LOOPS_MIN 0
#define SCAMPER_DO_TRACE_LOOPS_DEF 1 /* stop on the first loop found */
#define SCAMPER_DO_TRACE_LOOPS_MAX 255
#define SCAMPER_DO_TRACE_LOOPACTION_MIN 0
#define SCAMPER_DO_TRACE_LOOPACTION_DEF 0
#define SCAMPER_DO_TRACE_LOOPACTION_MAX 1
#define SCAMPER_DO_TRACE_PPS_MIN 1
#define SCAMPER_DO_TRACE_PPS_MAX 1000
#define SCAMPER_DO_TRACE_PPS_DEF 20
#define SCAMPER_DO_TRACE_SPORT_MIN 1
#define SCAMPER_DO_TRACE_SPORT_MAX 65535
#define SCAMPER_DO_TRACE_TOS_MIN 0
#define SCAMPER_DO_TRACE_TOS_DEF 0
#define SCAMPER_DO_TRACE_TOS_MAX 255
#define SCAMPER_DO_TRACE_WAIT_MIN 1
#define SCAMPER_DO_TRACE_WAIT_DEF 5
#define SCAMPER_DO_TRACE_WAIT_MAX 10
/*
* pmtud_L2_state
*
* this struct records state when inferring the MTU of the underlying media.
*
* when scamper has to discover the MTU of the link itself, it uses the L2
* table above to choose a suitable initial guess. it records the index
* into the L2 table into L2_idx.
*/
typedef struct pmtud_L2_state
{
int idx; /* index into the L2 table */
int lower; /* lower bounds of the L2 search space */
int upper; /* upper bounds of the L2 search space */
int in; /* probe size not to get a suitable response */
int out; /* size of probe to infer the underlying MTU */
scamper_trace_hop_t *hop; /* the last probe to obtain a response */
} pmtud_L2_state_t;
/*
* pmtud_TTL_state
*
* this struct records state when inferring the TTL range of hops that
* are responsible for not sending a fragmentation required message where
* one is required.
*/
typedef struct pmtud_TTL_state
{
int lower; /* lower bounds of the TTL search space */
int upper; /* upper bounds of the TTL search space */
scamper_trace_hop_t *hop; /* the last TTL probe to obtain a response */
} pmtud_TTL_state_t;
/*
* pmtud_L2
*
* this struct associates a known MTU with an index into an array.
*/
typedef struct pmtud_L2
{
int idx; /* index into the L2 array where this node resides */
int mtu; /* the MTU of the link */
char *descr; /* some description of the L2 media */
} pmtud_L2_t;
/*
* trace_probe
*
* this struct keeps state of each probe sent with the trace
*/
typedef struct trace_probe
{
struct timeval tx_tv; /* the time we transmitted the probe */
struct timeval rx_tv; /* the time we received the first answer */
scamper_addr_t *rx_mac; /* the mac addr where we received the first answer */
uint16_t rx; /* how many responses scamper got to the probe */
uint16_t size; /* the size of the probe sent */
uint8_t ttl; /* the TTL that was set for the probe */
uint8_t id; /* the attempt number made with ttl/size params */
uint8_t mode; /* the mode scamper was in when probe was sent */
uint8_t flags; /* the probe's flags */
} trace_probe_t;
#define TRACE_PROBE_FLAG_DL_TX 0x01
#define TRACE_PROBE_FLAG_DL_RX 0x02
#define TRACE_ALLOC_HOPS 16
/*
* trace_state
*
* this is a fairly large struct that keeps state for the traceroute
* process. it also deals with state in the PMTUD phase, if used.
*/
typedef struct trace_state
{
uint8_t mode; /* current trace mode scamper is in */
uint8_t ttl; /* ttl to set in the probe packet */
uint8_t attempt; /* attempt number at the current probe */
uint8_t loopc; /* count of loops so far */
uint8_t iloopc; /* count of ignored loops */
uint16_t alloc_hops; /* number of trace->hops allocated */
uint16_t payload_size; /* how much payload to include */
uint16_t header_size; /* size of headers */
scamper_fd_t *route; /* fd to query route socket with */
scamper_fd_t *icmp; /* fd to listen to icmp packets with */
scamper_fd_t *probe; /* fd to probe with */
scamper_fd_t *dl; /* struct to use with datalink access */
uint8_t *dl_hdr; /* header to use with datalink */
uint16_t dl_size; /* how large the header is */
trace_probe_t **probes; /* probes sent so far */
uint16_t id_next; /* next id to use in probes */
uint16_t id_max; /* maximum id available */
pmtud_L2_state_t *L2; /* state kept when doing L2 MTU search */
pmtud_TTL_state_t *TTL; /* state kept when doing a TTL search */
scamper_trace_hop_t *last_fragmsg; /* last fragmentation msg stored */
} trace_state_t;
const uint8_t MODE_TRACE = 0;
const uint8_t MODE_LASTDITCH = 1;
const uint8_t MODE_PMTUD_DEFAULT = 2;
const uint8_t MODE_PMTUD_SILENT_L2 = 3;
const uint8_t MODE_PMTUD_SILENT_TTL = 4;
const uint8_t MODE_PMTUD_BADSUGG = 5;
const uint8_t MODE_RTSOCK = 6;
#define MODE_MIN MODE_TRACE
#define MODE_MAX MODE_RTSOCK
/* the callback functions registered with the trace task */
static scamper_task_funcs_t trace_funcs;
/* address cache used to avoid reallocating the same address multiple times */
extern scamper_addrcache_t *addrcache;
/* temporary buffer shared amongst traceroutes */
static uint8_t *pktbuf = NULL;
static size_t pktbuf_len = 0;
/* socket used to obtain the MTU of a particular interface */
static int if_sock = -1;
/*
* these MTUs were largely taken from the NetBSD version of traceroute, and
* are used to choose a packet size to probe with in the absense of a
* Fragmentation Needed message.
*
* they have been annoted with their corresponding Layer 2 type, largely
* taken from RFC 1191
*/
static const pmtud_L2_t L2[] =
{
{ 0, 68, "RFC791 MTU"}, /* Official RFC 791 minimum MTU */
{ 1, 296, "P2P low delay"}, /* Point-to-Point links, (low delay) */
{ 2, 508, ""},
{ 3, 512, "NetBIOS"}, /* NetBIOS */
{ 4, 544, "DEC Portal"}, /* DEC IP Portal */
{ 5, 552, ""},
{ 6, 576, "v4 min MTU"}, /* X25 MTU, IPv4 Minimum MTU */
{ 7, 1006, "SLIP"}, /* SLIP */
{ 8, 1280, "v6 min MTU"}, /* IPv6 Minimum MTU */
{ 9, 1454, "PPPoE ADSL"}, /* an optimally sized PPPoE frame in DSL */
{10, 1480, "v4tun Ether"}, /* Ethernet MTU with tunnel over IPv4 */
{11, 1492, "IEEE 802.3"}, /* IEEE 802.3 */
{12, 1500, "Ethernet"}, /* Ethernet MTU */
{13, 1514, "Ethernet Max"}, /* Ethernet Max MTU */
{14, 1536, "Exp. Ether"}, /* Exp. Ethernet Nets */
{15, 2002, "IEEE 802.5"}, /* IEEE 802.5, Recommended MTU */
{16, 2048, "Wideband"}, /* Wideband Network */
{17, 4352, "FDDI"}, /* FDDI */
{18, 4464, "IEEE 802.5"}, /* IEEE 802.5, Maximum MTU */
{19, 4470, "IP over ATM"}, /* ATM / T3 / SONET SDH */
{20, 8166, "IEEE 802.4"}, /* IEEE 802.4 */
{21, 9000, "Broadcom GigE"}, /* Broadcom GigE MTU */
{22, 9192, "OC-192"}, /* OC-192 and other really fast media */
{23, 16110, "Intel GigE"}, /* Intel Pro 1000 MTU */
{24, 17914, "Token Ring"}, /* 16Mb IBM Token Ring */
{25, 65535, "IPv[46] MTU"} /* The IPv[46] Maximum MTU */
};
static const pmtud_L2_t *L2_1454 = &L2[9];
static const pmtud_L2_t *L2_1500 = &L2[12];
static const int L2_cnt = sizeof(L2) / sizeof(pmtud_L2_t);
#define TRACE_OPT_DPORT 1
#define TRACE_OPT_FIRSTHOP 2
#define TRACE_OPT_GAPLIMIT 3
#define TRACE_OPT_GAPACTION 4
#define TRACE_OPT_LOOPS 5
#define TRACE_OPT_LOOPACTION 6
#define TRACE_OPT_MAXTTL 7
#define TRACE_OPT_PMTUD 8
#define TRACE_OPT_PROTOCOL 9
#define TRACE_OPT_ATTEMPTS 10
#define TRACE_OPT_ALLATTEMPTS 11
#define TRACE_OPT_SPORT 12
#define TRACE_OPT_TOS 13
#define TRACE_OPT_WAIT 14
static const scamper_option_in_t trace_opts_in[] = {
{'d', NULL, TRACE_OPT_DPORT, SCAMPER_OPTION_TYPE_NUM},
{'f', NULL, TRACE_OPT_FIRSTHOP, SCAMPER_OPTION_TYPE_NUM},
{'g', NULL, TRACE_OPT_GAPLIMIT, SCAMPER_OPTION_TYPE_NUM},
{'G', NULL, TRACE_OPT_GAPACTION, SCAMPER_OPTION_TYPE_NUM},
{'l', NULL, TRACE_OPT_LOOPS, SCAMPER_OPTION_TYPE_NUM},
{'L', NULL, TRACE_OPT_LOOPACTION, SCAMPER_OPTION_TYPE_NUM},
{'m', NULL, TRACE_OPT_MAXTTL, SCAMPER_OPTION_TYPE_NUM},
{'M', NULL, TRACE_OPT_PMTUD, SCAMPER_OPTION_TYPE_NULL},
{'P', NULL, TRACE_OPT_PROTOCOL, SCAMPER_OPTION_TYPE_STR},
{'q', NULL, TRACE_OPT_ATTEMPTS, SCAMPER_OPTION_TYPE_NUM},
{'Q', NULL, TRACE_OPT_ALLATTEMPTS, SCAMPER_OPTION_TYPE_NULL},
{'s', NULL, TRACE_OPT_SPORT, SCAMPER_OPTION_TYPE_NUM},
{'t', NULL, TRACE_OPT_TOS, SCAMPER_OPTION_TYPE_NUM},
{'w', NULL, TRACE_OPT_WAIT, SCAMPER_OPTION_TYPE_NUM},
};
static const int trace_opts_cnt = SCAMPER_OPTION_COUNT(trace_opts_in);
/*
* if_getmtu
*
* given an interface index, return the MTU of it. return zero if
* we can't get the interface's MTU.
*/
static int if_getmtu(const int ifindex, uint16_t *ifmtu)
{
struct ifreq ifr;
int mtu;
assert(ifindex >= 0);
/* given the index, return the interface name to query */
if(if_indextoname((unsigned int)ifindex, ifr.ifr_name) == NULL)
{
printerror(errno, strerror, __func__, "could not if_indextoname");
return -1;
}
if(ioctl(if_sock, SIOCGIFMTU, &ifr) == -1)
{
printerror(errno, strerror, __func__, "could not SIOCGIFMTU");
return -1;
}
#if defined(__sun__)
mtu = ifr.ifr_metric;
#else
mtu = ifr.ifr_mtu;
#endif
if(mtu >= 0 && mtu <= 65535)
{
*ifmtu = mtu;
return 0;
}
return -1;
}
#if defined(__linux__) || defined(__sun__)
static int if_getmac(const int ifindex, uint8_t *mac)
{
struct ifreq ifr;
if(if_indextoname(ifindex, ifr.ifr_name) == NULL)
{
printerror(errno, strerror, __func__, "could not if_indextoname");
return -1;
}
#if defined(__linux__)
if(ioctl(if_sock, SIOCGIFHWADDR, &ifr) == -1)
{
printerror(errno, strerror, __func__, "could not SIOCGIFHWADDR");
return -1;
}
memcpy(mac, ifr.ifr_hwaddr.sa_data, 6);
#elif defined(__sun__)
if(ioctl(if_sock, SIOCGENADDR, &ifr) == -1)
{
printerror(errno, strerror, __func__, "could not SIOCGENADDR");
return -1;
}
memcpy(mac, ifr.ifr_enaddr, 6);
#endif
return 0;
}
#else
static int if_getmac(const int ifindex, uint8_t *mac)
{
struct if_msghdr *ifm;
struct sockaddr_dl *sdl;
int mib[6];
size_t len;
uint8_t *buf;
mib[0] = CTL_NET;
mib[1] = AF_ROUTE;
mib[2] = 0;
mib[3] = AF_LINK;
mib[4] = NET_RT_IFLIST;
mib[5] = ifindex;
if(sysctl(mib, 6, NULL, &len, NULL, 0) == -1)
{
printerror(errno, strerror, __func__, "could not sysctl buflen");
return -1;
}
if((buf = malloc(len)) == NULL)
{
printerror(errno, strerror, __func__, "could not malloc buf");
return -1;
}
if(sysctl(mib, 6, buf, &len, NULL, 0) < 0)
{
printerror(errno, strerror, __func__, "could not sysctl data");
free(buf);
return -1;
}
ifm = (struct if_msghdr *)buf;
sdl = (struct sockaddr_dl *)(buf+sizeof(struct if_msghdr));
memcpy(mac, LLADDR(sdl), 6);
free(buf);
return 0;
}
#endif
/*
* pmtud_L2_hop
*
* utility to replace the currently cached hop record recorded when scamper
* does the L2 MTU search.
*/
static void pmtud_L2_hop(trace_state_t *state, scamper_trace_hop_t *hop)
{
assert(state->L2 != NULL);
if(state->L2->hop != NULL) scamper_trace_hop_free(state->L2->hop);
state->L2->hop = hop;
return;
}
/*
* pmtud_L2_set_probesize
*
* given the lower and upper values of the PMTU search, suggest a packet
* size to probe next. apply a few heuristics to the search to try and
* find the PMTU to the next node faster.
*/
static void pmtud_L2_set_probesize(trace_state_t *state,
const int lower, const int upper)
{
int idx = state->L2->idx;
int size;
/* callers should detect end of L2 search before calling this function */
assert(lower + 1 != upper);
/* make sure the L2->idx parameter has been set (to something reasonable) */
assert(idx >= 0);
assert(idx < L2_cnt);
/* make sure the suggested window size is within the current window */
assert(state->L2->lower == -1 || lower >= state->L2->lower);
assert(state->L2->upper == -1 || upper <= state->L2->upper);
/*
* if we've narrowed it down to between two entries in the L2 table,
* then try one byte higher than the lower, as there's a fair chance
* the underlying mtu will be L2[idx].mtu.
*
* we make an exception if the lower bounds is Ethernet: there exists
* a strong possibility the underlying MTU is Ethernet, and the cost
* of guessing wrong [i.e. getting an unexpected response] is small.
*/
if(lower == 1500 || (lower == L2[idx].mtu && upper <= L2[idx+1].mtu))
{
size = lower + 1;
}
/*
* if there is a media MTU higher than the current lower bounds that
* is smaller than the upper bounds, then try it
*/
else if(lower >= L2[idx].mtu && L2[idx+1].mtu < upper)
{
size = L2[++idx].mtu;
}
/*
* if we did not get a response to the last media MTU probe, and there
* is a smaller known media MTU to try, then try it now
*/
else if(upper == L2[idx].mtu && lower < L2[idx-1].mtu)
{
size = L2[--idx].mtu;
}
/*
* scamper is operating between two known MTU types, do a binary chop
*/
else
{
size = (lower + upper) / 2;
}
state->attempt = 0;
state->payload_size = size - state->header_size;
state->L2->idx = idx;
state->L2->lower = lower;
state->L2->upper = upper;
return;
}
/*
* pmtud_L2_init
*
* utility to search the L2 table for a suitable initial probe size, based
* on known [to scamper] L2 media MTUs in relation to the last probe sent that
* went unacknowledged.
*/
static int pmtud_L2_init(trace_state_t *state)
{
pmtud_L2_state_t *L2s;
int size = state->header_size + state->payload_size;
int idx;
/*
* if the probe that was not answered is > 1500 bytes and scamper has
* not got a response to a packet 1500 bytes or larger yet, then
* forcibly try the ethernet MTU next, as the chances are good that the
* media will be plain old ethernet.
*/
if(size > 1500)
{
idx = L2_1500->idx;
}
/*
* if the probe that was not answered is > 1454 bytes, then forcibly try
* the lower bounds of X-over-ethernet types.
*/
else if(size > 1454)
{
idx = L2_1454->idx;
}
else
{
for(idx=0; idx<L2_cnt-1; idx++)
{
if(size > L2[idx].mtu && size <= L2[idx+1].mtu)
{
break;
}
}
}
if((L2s = malloc(sizeof(pmtud_L2_state_t))) == NULL)
{
return -1;
}
L2s->idx = idx;
L2s->hop = NULL;
L2s->lower = -1;
L2s->upper = size;
L2s->in = size;
L2s->out = -1;
state->L2 = L2s;
state->payload_size = L2[idx].mtu - state->header_size;
state->attempt = 0;
return 0;
}
/*
* pmtud_TTL_hop
*
* utility to replace the currently cached hop record recorded when scamper
* does the TTL search.
*/
static void pmtud_TTL_hop(trace_state_t *state, scamper_trace_hop_t *hop)
{
if(state->TTL->hop != NULL)
{
scamper_trace_hop_free(state->TTL->hop);
}
state->TTL->hop = hop;
return;
}
/*
* pmtud_TTL_set_probettl
*
* return: 0 if there are no more TTLs to probe, 1 if probing should continue
*/
static int pmtud_TTL_set_probettl(scamper_task_t *task,
const int lower, int upper)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
int cur;
/* check to see if we have to do any more TTL searching */
while(lower + 1 < upper)
{
/* halve the TTL space */
cur = (lower + upper) / 2;
/*
* check to see if experience at soliciting a TTL expired message has
* been good. skip TTLs that have been non-responsive
*/
while(cur < upper && trace->hops[cur-1] == NULL)
{
cur++;
}
/* scamper got a suitable TTL probe value, so we are done */
if(cur != upper)
{
state->TTL->lower = lower;
state->TTL->upper = upper;
state->ttl = cur;
state->attempt = 0;
return 1;
}
/*
* there are no TTLs above the half-way point to probe for, so try for
* ones lower
*/
upper = (lower + upper) / 2;
}
return 0;
}
/*
* hop_find
*
* check to see if there is any other hop in the trace with the
* same address
*/
static scamper_trace_hop_t *hop_find(const scamper_trace_t *trace,
const scamper_addr_t *addr)
{
scamper_trace_hop_t *hop;
uint16_t i;
for(i=0; i<trace->hop_count; i++)
{
for(hop = trace->hops[i]; hop != NULL; hop = hop->hop_next)
{
if(scamper_addr_cmp(hop->hop_addr, addr) == 0)
{
return hop;
}
}
}
return NULL;
}
/*
* pmtud_TTL_init
*
* initialise the bounds of a TTL search
*/
static int pmtud_TTL_init(scamper_task_t *task)
{
scamper_trace_hop_t *hop;
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
int lower, upper;
uint8_t turn_ttl;
if((state->TTL = malloc_zero(sizeof(pmtud_TTL_state_t))) == NULL)
{
return -1;
}
/*
* the packet size that is dropped silently is the size we are
* doing a TTL limited search with
*/
state->payload_size = state->L2->in - state->header_size;
/*
* use the last ICMP fragmentation required message recorded in the
* path MTU discovery phase to infer a suitable lower-bound for inferring
* the range of TTLs that could be responsible for not sending an ICMP
* fragmentation required message
*/
if(state->last_fragmsg == NULL)
{
lower = 0;
}
else
{
SCAMPER_TRACE_HOP_GET_TURN_TTL(state->last_fragmsg, turn_ttl);
if((lower = state->last_fragmsg->hop_probe_ttl - turn_ttl) < 1)
{
lower = 0;
}
}
/*
* the upper bound of TTLs to search is set by closest response past
* the hop that sends nothing
*/
if((hop = hop_find(trace, state->L2->hop->hop_addr)) != NULL)
{
upper = hop->hop_probe_ttl;
}
else
{
SCAMPER_TRACE_HOP_GET_TURN_TTL(state->L2->hop, turn_ttl);
upper = state->L2->hop->hop_probe_ttl - turn_ttl + 1;
}
/* if the TTL limited search is a null operation, then say so */
if(pmtud_TTL_set_probettl(task, lower, upper) == 0)
{
return 0;
}
return 1;
}
/*
* pmtud_hopins
*
* take the hop structure and put it into the list of hops based on the
* TTL distance into the path.
* XXX: this isn't what this function actually does.
*/
static void pmtud_hopins(scamper_trace_t *trace, scamper_trace_hop_t *hop)
{
scamper_trace_hop_t *cur, *pre;
assert(hop != NULL);
if((pre = trace->pmtud->hops) == NULL)
{
trace->pmtud->hops = hop;
return;
}
for(cur = pre->hop_next; cur != NULL; cur = cur->hop_next)
{
pre = cur;
}
pre->hop_next = hop;
hop->hop_next = cur;
return;
}
/*
* pmtu_L2_search_end
*
* scamper has had to infer the underlying next-hop MTU due to a pmtud
* fault. given the hop used to infer the nhmtu, insert that into the
* trace and tidy up.
*/
static int pmtud_L2_search_end(scamper_task_t *task)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_trace_hop_t *hop;
uint16_t out;
assert(state->L2->out >= 0);
assert(state->L2->out <= 65535);
out = state->L2->out;
/*
* copy details of the TTL-expired message furthest into the path
* into the trace if there is one to copy
*/
if(state->TTL != NULL)
{
/*
* if there was no TTL response with the large packet from anywhere
* in the path
*/
if(state->TTL->hop == NULL)
{
/*
* if the lowest TTL tried was zero, then we infer that the host
* itself has an MTU mismatch with the particular router it is
* using for the destination
*/
if(state->TTL->lower == 0)
{
scamper_tlv_set(&trace->pmtud->tlvs,
SCAMPER_TRACE_PMTUD_TLV_OUTMTU, 2, &out);
}
}
else
{
pmtud_hopins(trace, state->TTL->hop);
}
free(state->TTL);
state->TTL = NULL;
}
/*
* copy details of the hop to terminate the largest probe into
* the pmtu struct. hops between the TTL expired message (if we
* have one) and the ICMP unreach message have their PMTU inferred
*/
if((hop = state->L2->hop) != NULL)
{
pmtud_hopins(trace, hop);
state->last_fragmsg = hop;
free(state->L2);
state->L2 = NULL;
/*
* if the hop that we last recorded is a hop message that would
* ordinarily have caused scamper to stop PMTU discovery, then
* stop it now
*/
if(!SCAMPER_TRACE_HOP_IS_ICMP_PACKET_TOO_BIG(hop))
{
trace->pmtud->pmtu = hop->hop_probe_size;
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return 1;
}
}
if(state->L2 != NULL)
{
free(state->L2);
state->L2 = NULL;
}
state->payload_size = out - state->header_size;
state->mode = MODE_PMTUD_DEFAULT;
state->attempt = 0;
state->ttl = 255;
return 0;
}
/*
* trace_ipid_fudge
*
* play games with the embedded IP ID, which may come back with a different
* IP ID than what was sent; return the ID of the corresponding probe in *id.
* this code was inspired by information from David Malone.
*
* the IPID transmitted is assigned from a counter (state->id_next) which
* starts from one -- *not* zero. this is so systems that zero the IPID
* will not confuse this algorithm.
*
* the IPID is transmitted by scamper in network byte order.
*
*/
static int trace_ipid_fudge(const trace_state_t *state,
const uint16_t ipid, uint16_t *id)
{
/* ensure the IP ID is not zero */
if(ipid == 0)
{
return -1;
}
/* check if the IP ID is in range */
if(ipid <= state->id_next)
{
*id = ipid - 1;
return 0;
}
/* check if the IP ID was incremented */
if(ipid == state->id_next + 1)
{
scamper_debug(__func__, "ip id one greater than sent");
*id = ipid - 2;
return 0;
}
/* check if the IP ID was byte swapped. XXX: is this correct? */
if(byteswap16(ipid) <= state->id_next)
{
scamper_debug(__func__, "ip id byte swapped");
*id = byteswap16(ipid) - 1;
return 0;
}
return -1;
}
/*
* trace_stop
*
* set the trace's stop parameters to whatever it is passed
*/
static void trace_stop(scamper_trace_t *trace,
const uint8_t reason, const uint8_t data)
{
/* if we've already set a stop reason, then don't clobber it */
if(trace->stop_reason != SCAMPER_TRACE_STOP_NONE)
{
scamper_debug(__func__, "reason %d/%d preceeds %d/%d",
trace->stop_reason, trace->stop_data, reason, data);
return;
}
trace->stop_reason = reason;
trace->stop_data = data;
return;
}
static void trace_stop_completed(scamper_trace_t *trace)
{
trace_stop(trace, SCAMPER_TRACE_STOP_COMPLETED, 0);
return;
}
static void trace_stop_gaplimit(scamper_trace_t *trace)
{
trace_stop(trace, SCAMPER_TRACE_STOP_GAPLIMIT, 0);
return;
}
static void trace_stop_error(scamper_trace_t *trace, int error)
{
trace_stop(trace, SCAMPER_TRACE_STOP_ERROR, error);
return;
}
static void trace_stop_hoplimit(scamper_trace_t *trace)
{
trace_stop(trace, SCAMPER_TRACE_STOP_HOPLIMIT, 0);
return;
}
/*
* trace_isloop
*
* given a trace and a hop record, determine if there is a loop.
*/
static int trace_isloop(const scamper_trace_t *trace,
const scamper_trace_hop_t *hop,
trace_state_t *state)
{
scamper_trace_hop_t *tmp;
int i;
/* need at least a couple of probes first */
if(hop->hop_probe_ttl <= trace->firsthop)
{
return 0;
}
/*
* check to see if the address has already been seen this hop; if it is,
* then we've already checked this address for loops so we don't need to
* check it again.
*/
for(tmp = trace->hops[hop->hop_probe_ttl-1]; tmp != hop; tmp = tmp->hop_next)
{
if(scamper_addr_cmp(hop->hop_addr, tmp->hop_addr) == 0)
{
return 0;
}
}
/* compare all hop records until the hop prior to this one */
for(i=hop->hop_probe_ttl-2; i>=trace->firsthop-1; i--)
{
for(tmp = trace->hops[i]; tmp != NULL; tmp = tmp->hop_next)
{
assert(i+1 == tmp->hop_probe_ttl);
/* if the addresses match, then there is a loop */
if(scamper_addr_cmp(hop->hop_addr, tmp->hop_addr) == 0)
{
/*
* if the loop is between adjacent hops, check the loopaction
* parameter for what we should do
*/
if(tmp->hop_probe_ttl + 1 == hop->hop_probe_ttl)
{
/*
* the loopaction parameter has values 0 .. 255; currently
* the loopaction parameter counts the number of loops
* between adjacent hops to ignore.
*/
if(++state->iloopc <= trace->loopaction)
return 0;
}
/* check if the loop condition is met */
state->loopc++;
if(state->loopc >= trace->loops)
{
return 1;
}
/* count the loop just once for this hop */
break;
}
}
}
return 0;
}
/*
* trace_hopins
*
* insert the hop record into the hop list at the appropriate place
*/
static int trace_hopins(scamper_trace_hop_t **hops, scamper_trace_hop_t *hop)
{
scamper_trace_hop_t *pre, *cur;
/* insert at head if no other hop recorded */
if((cur = *hops) == NULL)
{
*hops = hop;
hop->hop_next = NULL;
return 0;
}
/* search for the place to insert this hop record */
pre = NULL;
while(cur != NULL && cur->hop_probe_id <= hop->hop_probe_id)
{
pre = cur;
cur = cur->hop_next;
}
/* the place to insert is at the head of the list */
if(pre == NULL)
{
*hops = hop;
}
else
{
pre->hop_next = hop;
}
hop->hop_next = cur;
return 0;
}
/*
* trace_handlerror
*
* the code encountered some error when doing the traceroute, so stop the
* trace now.
*/
static int trace_handleerror(scamper_task_t *task, const int error)
{
trace_stop_error((scamper_trace_t *)task->data, error);
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return 0;
}
/*
* trace_hop
*
* this function creates a generic hop record with the basic details from
* the probe structure copied in, as well as an address based on the details
* passed in
*/
static scamper_trace_hop_t *trace_hop(const trace_probe_t *probe,
const int af, const void *addr)
{
scamper_trace_hop_t *hop;
int type;
/* determine the scamper address type to use from the address family */
if(af == AF_INET) type = SCAMPER_ADDR_TYPE_IPV4;
else if(af == AF_INET6) type = SCAMPER_ADDR_TYPE_IPV6;
else return NULL;
if((hop = scamper_trace_hop_alloc()) == NULL)
{
return NULL;
}
if((hop->hop_addr = scamper_addrcache_get(addrcache, type, addr)) == NULL)
{
scamper_trace_hop_free(hop);
return NULL;
}
hop->hop_probe_ttl = probe->ttl;
hop->hop_probe_id = probe->id + 1;
hop->hop_probe_size = probe->size;
/*
* if the probe's datalink tx timestamp flag is set, scamper has a tx
* timestamp recorded
*/
if(probe->flags & TRACE_PROBE_FLAG_DL_TX)
{
hop->hop_flags |= SCAMPER_TRACE_HOP_FLAG_TS_DL_TX;
}
return hop;
}
/*
* trace_icmp_hop
*
* given a trace probe and an ICMP response, allocate and initialise a
* scamper_trace_hop record.
*/
static scamper_trace_hop_t *trace_icmp_hop(scamper_trace_t *trace,
trace_probe_t *probe,
scamper_icmp_resp_t *ir)
{
scamper_trace_hop_t *hop;
scamper_addr_t addr;
uint16_t dl;
uint16_t cn, ct;
int off;
/* get a pointer to the source address of the ICMP response */
if(scamper_icmp_resp_src(ir, &addr) != 0)
{
return NULL;
}
/* create a generic hop record without any special bits filled out */
if((hop = trace_hop(probe, ir->ir_af, addr.addr)) == NULL)
{
return NULL;
}
/* fill out the basic bits of the hop structure */
hop->hop_reply_size = ir->ir_ip_size;
hop->hop_icmp_type = ir->ir_icmp_type;
hop->hop_icmp_code = ir->ir_icmp_code;
/*
* we cannot depend on the TTL field of the IP packet being made available,
* so we signal explicitly when the reply ttl is valid
*/
if(ir->ir_ip_ttl != -1)
{
hop->hop_reply_ttl = ir->ir_ip_ttl;
hop->hop_flags |= SCAMPER_TRACE_HOP_FLAG_REPLY_TTL;
}
/*
* if the probe's datalink rx timestamp flag is set, scamper has a rx
* timestamp recorded
*/
if(probe->flags & TRACE_PROBE_FLAG_DL_RX)
{
hop->hop_flags |= SCAMPER_TRACE_HOP_FLAG_TS_DL_RX;
timeval_rtt(&hop->hop_rtt, &probe->tx_tv, &probe->rx_tv);
}
else
{
timeval_rtt(&hop->hop_rtt, &probe->tx_tv, &ir->ir_rx);
if(ir->ir_flags & SCAMPER_ICMP_RESP_FLAG_KERNRX)
{
hop->hop_flags |= SCAMPER_TRACE_HOP_FLAG_TS_SOCK_RX;
}
}
if(SCAMPER_ICMP_RESP_IS_PACKET_TOO_BIG(ir))
{
if(scamper_tlv_set(&hop->hop_tlvs, SCAMPER_TRACE_HOP_TLV_NHMTU,
2, &ir->ir_icmp_nhmtu) == NULL)
{
goto err;
}
}
if(ir->ir_af == AF_INET)
{
if(scamper_tlv_set(&hop->hop_tlvs, SCAMPER_TRACE_HOP_TLV_REPLY_IPID,
2, &ir->ir_ip_id) == NULL ||
scamper_tlv_set(&hop->hop_tlvs, SCAMPER_TRACE_HOP_TLV_REPLY_IPTOS,
1, &ir->ir_ip_tos) == NULL)
{
goto err;
}
}
if(SCAMPER_ICMP_RESP_INNER_IS_SET(ir))
{
/*
* IPv4: record ToS byte
* IPv6: might pay to record traffic class byte here.
*/
if(ir->ir_af == AF_INET &&
scamper_tlv_set(&hop->hop_tlvs, SCAMPER_TRACE_HOP_TLV_INNER_IPTOS,
1, &ir->ir_inner_ip_tos) == NULL)
{
goto err;
}
if(ir->ir_inner_ip_ttl != 1)
{
if(scamper_tlv_set(&hop->hop_tlvs, SCAMPER_TRACE_HOP_TLV_INNER_IPTTL,
1, &ir->ir_inner_ip_ttl) == NULL)
{
goto err;
}
}
if(ir->ir_inner_ip_size != probe->size)
{
if(scamper_tlv_set(&hop->hop_tlvs, SCAMPER_TRACE_HOP_TLV_INNER_IPLEN,
2, &ir->ir_inner_ip_size) == NULL)
{
goto err;
}
}
}
/*
* if ICMP extensions are included, then parse and include them.
* note that the icmp extension header is included in ir_ext,
* but the hop structure only includes the extensions themselves.
*/
if(ir->ir_ext != NULL)
{
/* start at offset 4 so the extension header is skipped */
for(off = 4; off + 4 < ir->ir_extlen; off += dl)
{
/* extract the length field */
memcpy(&dl, ir->ir_ext+off, 2);
dl = ntohs(dl);
/* make sure there is enough in the packet left */
if(off + dl < ir->ir_extlen)
break;
cn = ir->ir_ext[off+2];
ct = ir->ir_ext[off+3];
if(dl < 8)
{
scamper_debug(__func__, "icmp ext %d/%d/%d ignored", cn, ct, dl);
continue;
}
if(scamper_trace_hop_icmpext_add(hop, cn, ct, dl-4,
ir->ir_ext+off+4) != 0)
{
printerror(errno, strerror, __func__,
"could not add icmp ext %d/%d/%d", cn, ct, dl);
goto err;
}
}
}
/* record the fact that we have a hop record thanks to this probe */
if(probe->rx != 65535) probe->rx++;
return hop;
err:
scamper_trace_hop_free(hop);
return NULL;
}
static scamper_trace_hop_t *trace_tcp_hop(trace_probe_t *probe,
scamper_dl_rec_t *dl)
{
scamper_trace_hop_t *hop;
/* create a generic hop record without any special bits filled out */
if((hop = trace_hop(probe, dl->dl_af, dl->dl_ip_src)) == NULL)
{
return NULL;
}
/* fill out the basic bits of the hop structure */
hop->hop_reply_size = dl->dl_ip_size;
hop->hop_reply_ttl = dl->dl_ip_ttl;
hop->hop_tcp_flags = dl->dl_tcp_flags;
timeval_rtt(&hop->hop_rtt, &probe->tx_tv, &dl->dl_tv);
/* set the flags that are known to apply to this hop record */
hop->hop_flags |= (SCAMPER_TRACE_HOP_FLAG_REPLY_TTL |
SCAMPER_TRACE_HOP_FLAG_TCP |
SCAMPER_TRACE_HOP_FLAG_TS_DL_RX);
if(dl->dl_af == AF_INET)
{
if(scamper_tlv_set(&hop->hop_tlvs, SCAMPER_TRACE_HOP_TLV_REPLY_IPID,
2, &dl->dl_ip_id) == NULL ||
scamper_tlv_set(&hop->hop_tlvs, SCAMPER_TRACE_HOP_TLV_REPLY_IPTOS,
1, &dl->dl_ip_tos) == NULL)
{
goto err;
}
}
return hop;
err:
scamper_trace_hop_free(hop);
return NULL;
}
/*
* trace_next_mode
*
* if the trace is going into another mode, this function figures out
* which mode to put it into
*/
static void trace_next_mode(scamper_task_t *task)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
uint16_t ifmtu;
int ifindex;
if((trace->flags & SCAMPER_TRACE_FLAG_PMTUD) == 0 ||
trace->stop_reason == SCAMPER_TRACE_STOP_HOPLIMIT ||
trace->stop_reason == SCAMPER_TRACE_STOP_GAPLIMIT ||
trace->stop_reason == SCAMPER_TRACE_STOP_LOOP ||
trace->stop_reason == SCAMPER_TRACE_STOP_NONE)
{
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return;
}
/* if the interface's MTU is useless, then we can't do PMTUD */
scamper_fd_ifindex(state->dl, &ifindex);
if(if_getmtu(ifindex, &ifmtu) == -1 || ifmtu <= state->header_size)
{
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return;
}
if((trace->pmtud = malloc_zero(sizeof(struct scamper_trace_pmtud))) == NULL)
{
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return;
}
trace->pmtud->ifmtu = ifmtu;
state->attempt = 0;
state->mode = MODE_PMTUD_DEFAULT;
state->payload_size = ifmtu - state->header_size;
state->ttl = 255;
scamper_queue_probe(task->queue);
return;
}
/*
* trace_stop_reason
*
* check to see if we have a stop condition based on the hop record
*/
static void trace_stop_reason(scamper_trace_t *trace, scamper_trace_hop_t *hop,
trace_state_t *state,
uint8_t *stop_reason, uint8_t *stop_data)
{
int rc;
if(SCAMPER_TRACE_HOP_IS_ICMP_UNREACH_PORT(hop))
{
*stop_reason = SCAMPER_TRACE_STOP_COMPLETED;
*stop_data = 0;
}
else if(SCAMPER_TRACE_HOP_IS_ICMP_UNREACH(hop))
{
*stop_reason = SCAMPER_TRACE_STOP_UNREACH;
*stop_data = hop->hop_icmp_code;
}
else if(SCAMPER_TRACE_HOP_IS_ICMP_ECHO_REPLY(hop))
{
*stop_reason = SCAMPER_TRACE_STOP_COMPLETED;
*stop_data = 0;
}
else if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV6 &&
hop->hop_icmp_type == ICMP6_PACKET_TOO_BIG)
{
*stop_reason = SCAMPER_TRACE_STOP_ICMP;
*stop_data = hop->hop_icmp_type;
}
else if(trace->loops != 0 && (rc = trace_isloop(trace, hop, state)) != 0)
{
*stop_reason = SCAMPER_TRACE_STOP_LOOP;
*stop_data = 0;
}
else if(scamper_addr_cmp(trace->dst, hop->hop_addr) == 0)
{
/*
* in IPv6, we can have anonymous interfaces on the path that
* send ICMP errors 'spoofing' their source address as the
* destination we sent. if we get a TTL expired / fragmentation
* needed message on the path from the 'destination address' then
* it is an anonymous interface
*/
if(trace->dst->type != SCAMPER_ADDR_TYPE_IPV6 ||
hop->hop_icmp_type == ICMP6_DST_UNREACH)
{
*stop_reason = SCAMPER_TRACE_STOP_COMPLETED;
*stop_data = 0;
}
else
{
*stop_reason = SCAMPER_TRACE_STOP_NONE;
*stop_data = 0;
}
}
else
{
*stop_reason = SCAMPER_TRACE_STOP_NONE;
*stop_data = 0;
}
return;
}
/*
* handleicmp_trace
*
* we received an ICMP response in the traceroute state. check to see
* if the probe is in sequence, and adjust the trace accordingly.
*/
static int handleicmp_trace(scamper_task_t *task,
scamper_icmp_resp_t *ir,
trace_probe_t *probe)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_trace_hop_t *hop;
uint8_t stop_reason;
uint8_t stop_data;
int cwh = 0;
/* we should only have to deal with probes sent while in the trace state */
if(probe->mode != MODE_TRACE)
{
return 0;
}
/* create a hop record and insert it into the trace */
if((hop = trace_icmp_hop(trace, probe, ir)) == NULL)
{
return -1;
}
trace_hopins(&trace->hops[hop->hop_probe_ttl-1], hop);
/* if the response is for the current working hop */
if(hop->hop_probe_ttl - 1 == trace->hop_count)
{
/* current working hop */
cwh = 1;
/* if we are sending all allotted probes to the target */
if(trace->flags & SCAMPER_TRACE_FLAG_ALLATTEMPTS)
{
/*
* if we get an out of order reply, then we go back to waiting for
* the one we just probed for
*/
if(probe->id+1 != state->attempt)
{
return 0;
}
/*
* this response is for the last probe sent. if there are still
* probes to send for this hop, then send the next one
*/
if(state->attempt < trace->attempts)
{
scamper_queue_probe(task->queue);
return 0;
}
}
trace->hop_count++;
state->attempt = 0;
state->ttl++;
}
/* check to see if we have a stop reason from the ICMP response */
trace_stop_reason(trace, hop, state, &stop_reason, &stop_data);
if(stop_reason != SCAMPER_TRACE_STOP_NONE)
{
/* did we get a stop condition out of all that? */
trace_stop(trace, stop_reason, stop_data);
trace_next_mode(task);
}
else if(trace->hop_count == 255 || trace->hop_count == trace->hoplimit)
{
/* if not, has the hop limit now reached? */
trace_stop_hoplimit(trace);
trace_next_mode(task);
}
else if(cwh != 0)
{
/* if not, keep probing */
scamper_queue_probe(task->queue);
}
return 0;
}
/*
* handleicmp_lastditch
*
* we received an ICMP response while checking if the end-host is
* responsive.
*/
static int handleicmp_lastditch(scamper_task_t *task,
scamper_icmp_resp_t *ir,
trace_probe_t *probe)
{
scamper_trace_t *trace = task->data;
scamper_trace_hop_t *hop;
if(probe->mode == MODE_TRACE)
{
/* record the response in the trace */
if((hop = trace_icmp_hop(trace, probe, ir)) == NULL)
{
return -1;
}
trace_hopins(&trace->hops[hop->hop_probe_ttl-1], hop);
}
else if(probe->mode == MODE_LASTDITCH)
{
if((hop = trace_icmp_hop(trace, probe, ir)) == NULL)
{
return -1;
}
trace_hopins(&trace->lastditch, hop);
trace_stop_gaplimit((scamper_trace_t *)task->data);
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
}
return 0;
}
static int handleicmp_pmtud_default(scamper_task_t *task,
scamper_icmp_resp_t *ir,
trace_probe_t *probe)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_trace_hop_t *hop;
/*
* if the response is for a probe that fits with the current
* probing details, then record it
*/
if(probe->mode == MODE_PMTUD_DEFAULT &&
probe->size == state->header_size + state->payload_size)
{
if((hop = trace_icmp_hop(trace, probe, ir)) == NULL)
{
return -1;
}
pmtud_hopins(trace, hop);
state->last_fragmsg = hop;
if(SCAMPER_ICMP_RESP_IS_PACKET_TOO_BIG(ir))
{
/*
* if the fragmentation required message did not include the
* suggested packet size for the next hop, or if the suggested
* MTU is larger than (or the same size) as the probe packet, then
* abandon the pmtud operation at this point
*/
if(ir->ir_icmp_nhmtu == 0 || ir->ir_icmp_nhmtu >= probe->size)
{
state->mode = MODE_PMTUD_BADSUGG;
pmtud_L2_init(state);
scamper_queue_probe(task->queue);
return 0;
}
/*
* if the message supplied an MTU to use, but it is too small
* to be probed, then stop probing here.
*/
if(ir->ir_icmp_nhmtu < state->header_size)
{
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return 0;
}
state->attempt = 0;
state->payload_size = ir->ir_icmp_nhmtu - state->header_size;
scamper_queue_probe(task->queue);
}
else if(SCAMPER_ICMP_RESP_IS_TTL_EXP(ir) ||
SCAMPER_ICMP_RESP_IS_UNREACH(ir) ||
SCAMPER_ICMP_RESP_IS_ECHO_REPLY(ir))
{
trace->pmtud->pmtu = probe->size;
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
}
}
return 0;
}
static int handleicmp_pmtud_silent_L2(scamper_task_t *task,
scamper_icmp_resp_t *ir,
trace_probe_t *probe)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_trace_hop_t *hop;
assert(state->L2 != NULL);
/*
* if we get a response that is out of the bounds we are searching, it
* could be a delayed message. at the moment, we just ignore the response.
*/
if(probe->size < state->L2->lower || state->L2->upper <= probe->size)
{
scamper_debug(__func__, "L2 search %d < %d || %d <= %d",
probe->size, state->L2->lower,
state->L2->upper, probe->size);
return 0;
}
/* record the hop details */
if((hop = trace_icmp_hop(trace, probe, ir)) == NULL)
{
return -1;
}
pmtud_L2_hop(state, hop);
/*
* if there is still space to search, reduce the search space and send
* another probe
*/
if(probe->size + 1 != state->L2->upper)
{
/*
* raise the lower bounds of our search based on successfully
* receiving a response for a given packet size.
*/
pmtud_L2_set_probesize(state, probe->size, state->L2->upper);
}
else
{
state->L2->lower = state->L2->out = probe->size;
if(pmtud_TTL_init(task) == 1)
{
state->mode = MODE_PMTUD_SILENT_TTL;
}
else
{
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return 0;
}
}
scamper_queue_probe(task->queue);
return 0;
}
static int handleicmp_pmtud_silent_TTL(scamper_task_t *task,
scamper_icmp_resp_t *ir,
trace_probe_t *probe)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_trace_hop_t *hop;
/* we got a TTL expired message */
if(SCAMPER_ICMP_RESP_IS_TTL_EXP(ir))
{
/* record the hop details */
if((hop = trace_icmp_hop(trace, probe, ir)) == NULL)
{
return -1;
}
pmtud_TTL_hop(state, hop);
/* if there is no more TTL space to search, then we are done */
if(pmtud_TTL_set_probettl(task, probe->ttl, state->TTL->upper) == 0)
{
/*
* if we are not finished with PMTU yet, put the trace back in
* the queue
*/
if(pmtud_L2_search_end(task) == 1)
{
return 0;
}
}
}
/*
* if we get a fragmentation required message during a TTL limited
* search for the MTU inferred, then record the message and stop
* the TTL limited search
*/
else if(SCAMPER_ICMP_RESP_IS_PACKET_TOO_BIG(ir) &&
ir->ir_icmp_nhmtu == state->L2->out)
{
/* record the hop details */
if((hop = trace_icmp_hop(trace, probe, ir)) == NULL)
{
return -1;
}
pmtud_hopins((scamper_trace_t *)task->data, hop);
state->attempt = 0;
state->payload_size = ir->ir_icmp_nhmtu - state->header_size;
state->ttl = 255;
state->mode = MODE_PMTUD_DEFAULT;
free(state->L2); state->L2 = NULL;
free(state->TTL); state->TTL = NULL;
}
/* put the trace back into the probe queue */
scamper_queue_probe(task->queue);
return 0;
}
/*
* handleicmp_pmtud_badsugg
*
* we are in the badsugg state, which is used to infer a 'correct' next-hop
* mtu size when the suggested packet size is no help.
*/
static int handleicmp_pmtud_badsugg(scamper_task_t *task,
scamper_icmp_resp_t *ir,
trace_probe_t *probe)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_trace_hop_t *hop;
scamper_addr_t addr;
int upper, lower;
if(scamper_icmp_resp_src(ir, &addr) != 0)
{
return -1;
}
/*
* adjust the window we are searching based on where the response came
* from and the size of the probe that caused the response
*/
if(scamper_addr_cmp(state->last_fragmsg->hop_addr, &addr) == 0)
{
lower = state->L2->lower;
upper = probe->size;
}
else
{
lower = probe->size;
upper = state->L2->upper;
/* replace the layer-2 hop we get a response for with this hop */
if((hop = trace_icmp_hop(trace, probe, ir)) == NULL)
{
return -1;
}
pmtud_L2_hop(state, hop);
}
if(lower + 1 != upper)
{
pmtud_L2_set_probesize(state, lower, upper);
}
else
{
/* terminate the search now */
state->L2->lower = state->L2->out = lower;
state->L2->upper = upper;
/* if the pmtud is completed, then move on */
if(pmtud_L2_search_end(task) == 1)
{
return 0;
}
}
/* put the trace back into the probe queue */
scamper_queue_probe(task->queue);
return 0;
}
static int do_trace_handle_icmp(scamper_task_t *task, scamper_icmp_resp_t *ir)
{
static int (*const func[])(scamper_task_t *, scamper_icmp_resp_t *,
trace_probe_t *) = {
handleicmp_trace, /* MODE_TRACE == 0x00 */
handleicmp_lastditch, /* MODE_LASTDITCH == 0x01 */
handleicmp_pmtud_default, /* MODE_PMTUD_DEFAULT == 0x02 */
handleicmp_pmtud_silent_L2, /* MODE_PMTUD_SILENT_L2 == 0x03 */
handleicmp_pmtud_silent_TTL, /* MODE_PMTUD_SILENT_TTL == 0x04 */
handleicmp_pmtud_badsugg, /* MODE_PMTUD_BADSUGG == 0x05 */
NULL, /* MODE_RTSOCK == 0x06 */
};
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
uint16_t id;
uint8_t proto;
assert(state->mode <= MODE_MAX);
/*
* if the trace is in a mode that does not handle ICMP responses, then
* stop now
*/
if(func[state->mode] == NULL)
{
return 0;
}
if(trace->type == SCAMPER_TRACE_TYPE_UDP ||
trace->type == SCAMPER_TRACE_TYPE_UDP_PARIS)
{
/* if the ICMP type is not something that we care for, then drop it */
if(SCAMPER_ICMP_RESP_IS_TTL_EXP(ir) == 0 &&
SCAMPER_ICMP_RESP_IS_UNREACH(ir) == 0 &&
SCAMPER_ICMP_RESP_IS_PACKET_TOO_BIG(ir) == 0)
{
return 0;
}
/*
* if the ICMP response does not reference a UDP probe sent from our
* source port to a destination probe we're likely to have probed, then
* ignore the packet
*/
if(SCAMPER_ICMP_RESP_INNER_IS_SET(ir) == 0 ||
ir->ir_inner_ip_proto != IPPROTO_UDP ||
ir->ir_inner_udp_sport != trace->sport)
{
return 0;
}
if(trace->type == SCAMPER_TRACE_TYPE_UDP)
{
if(ir->ir_inner_udp_dport < trace->dport ||
ir->ir_inner_udp_dport >= trace->dport+state->id_next)
{
return 0;
}
/* XXX: handle wrap-around */
id = ir->ir_inner_udp_dport - trace->dport;
}
else if(trace->type == SCAMPER_TRACE_TYPE_UDP_PARIS)
{
if(ir->ir_inner_udp_dport != trace->dport)
{
return 0;
}
if(ir->ir_af == AF_INET)
{
if(ir->ir_inner_udp_sum == ir->ir_inner_ip_id &&
ir->ir_inner_udp_sum != 0)
{
id = ntohs(ir->ir_inner_udp_sum) - 1;
}
else if(trace_ipid_fudge(state, ir->ir_inner_ip_id, &id) != 0)
{
return 0;
}
}
else
{
if(ir->ir_inner_udp_sum == 0)
{
return 0;
}
id = ntohs(ir->ir_inner_udp_sum) - 1;
}
}
else return 0;
}
else if(trace->type == SCAMPER_TRACE_TYPE_ICMP_ECHO ||
trace->type == SCAMPER_TRACE_TYPE_ICMP_ECHO_PARIS)
{
/* if the ICMP type is not something that we care for, then drop it */
if(SCAMPER_ICMP_RESP_IS_ECHO_REPLY(ir) == 0)
{
if(SCAMPER_ICMP_RESP_IS_TTL_EXP(ir) == 0 &&
SCAMPER_ICMP_RESP_IS_UNREACH(ir) == 0 &&
SCAMPER_ICMP_RESP_IS_PACKET_TOO_BIG(ir) == 0)
{
return 0;
}
if(ir->ir_af == AF_INET) proto = IPPROTO_ICMP;
else if(ir->ir_af == AF_INET6) proto = IPPROTO_ICMPV6;
else return 0;
if(SCAMPER_ICMP_RESP_INNER_IS_SET(ir) == 0 ||
ir->ir_inner_ip_proto != proto ||
ir->ir_inner_icmp_id != trace->sport ||
ir->ir_inner_icmp_seq >= state->id_next)
{
return 0;
}
id = ir->ir_inner_icmp_seq;
}
else
{
if(ir->ir_icmp_id != trace->sport ||
ir->ir_icmp_seq >= state->id_next)
{
return 0;
}
id = ir->ir_icmp_seq;
}
}
else if(trace->type == SCAMPER_TRACE_TYPE_TCP)
{
/* if the ICMP type is not something that we care for, then drop it */
if(SCAMPER_ICMP_RESP_IS_TTL_EXP(ir) == 0 &&
SCAMPER_ICMP_RESP_IS_UNREACH(ir) == 0 &&
SCAMPER_ICMP_RESP_IS_PACKET_TOO_BIG(ir) == 0)
{
return 0;
}
/*
* if the ICMP response does not reference a TCP probe sent from our
* source port to the destination port specified then ignore the
* ICMP packet
*/
if(SCAMPER_ICMP_RESP_INNER_IS_SET(ir) == 0 ||
ir->ir_inner_ip_proto != IPPROTO_TCP ||
ir->ir_inner_tcp_sport != trace->sport ||
ir->ir_inner_tcp_dport != trace->dport)
{
return 0;
}
if(ir->ir_af == AF_INET)
{
/* determine which probe id the ip id corresponds to */
if(trace_ipid_fudge(state, ir->ir_inner_ip_id, &id) != 0)
{
return 0;
}
}
else
{
if(ir->ir_inner_ip_flow == 0)
{
return 0;
}
id = ir->ir_inner_ip_flow - 1;
}
}
else
{
return 0;
}
if(id < state->id_next)
{
func[state->mode](task, ir, state->probes[id]);
}
return 0;
}
/*
* timeout_trace
*
* this function is called if the trace timed out on the wait queue, and
* all allotted attempts have been sent.
*/
static int timeout_trace(scamper_task_t *task)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_trace_hop_t *hop;
int i, deadpath;
uint8_t stop_reason, stop_data;
/* we tried this hop, so move onto the next */
trace->hop_count++;
state->ttl++;
/*
* if we probed for all attempts on the hop, then check to see if we
* got any responses on this hop, and if we did, check to see if we
* should stop probing this target yet
*/
if(trace->flags & SCAMPER_TRACE_FLAG_ALLATTEMPTS)
{
for(hop = trace->hops[trace->hop_count-1];hop != NULL; hop=hop->hop_next)
{
/*
* first, check to see if there is a reason to stop probing with
* this particular hop record
*/
trace_stop_reason(trace, hop, state, &stop_reason, &stop_data);
if(stop_reason != SCAMPER_TRACE_STOP_NONE)
{
trace_stop(trace, stop_reason, stop_data);
trace_next_mode(task);
return 0;
}
}
}
if(trace->hop_count == 255 || trace->hop_count == trace->hoplimit)
{
trace_stop_hoplimit(trace);
trace_next_mode(task);
return 0;
}
/*
* if we haven't checked to see if the path is dead yet, check to see
* if we should do so at this time. a dead path is defined as a path
* that has an unresponsive target host, which we stop tracing after
* the gaplimit is reached.
*/
if(trace->hop_count - (trace->firsthop - 1) >= trace->gaplimit)
{
deadpath = 1;
for(i=0; i<trace->gaplimit; i++)
{
if(trace->hops[trace->hop_count-1-i] != NULL)
{
deadpath = 0;
break;
}
}
if(deadpath != 0)
{
if(trace->gapaction == SCAMPER_TRACE_GAPACTION_LASTDITCH)
{
state->mode = MODE_LASTDITCH;
state->ttl = 255;
}
else
{
trace_stop_gaplimit(trace);
trace_next_mode(task);
}
}
}
return 0;
}
static int timeout_lastditch(scamper_task_t *task)
{
/* we received no responses to any of the last-ditch probes */
trace_stop_gaplimit((scamper_trace_t *)task->data);
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return 0;
}
static int timeout_pmtud_default(scamper_task_t *task)
{
trace_state_t *state = task->state;
pmtud_L2_init(state);
state->mode = MODE_PMTUD_SILENT_L2;
return 0;
}
static int timeout_pmtud_silent_L2(scamper_task_t *task)
{
trace_state_t *state = task->state;
int size = state->header_size + state->payload_size;
/*
* have we scanned the L2 table to the official minimum MTU?
* if we have, then PMTU fails and we abort.
*/
if(state->L2->idx == 0)
{
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
return 0;
}
/*
* we did not get a response for this probe size
* if we can halve the search space again, then do that
*/
if(state->L2->lower + 1 != size)
{
pmtud_L2_set_probesize(state, state->L2->lower, size);
}
else
{
state->L2->out = state->L2->lower;
/* set the bounds of the TTL search */
if(pmtud_TTL_init(task) == 1)
{
state->mode = MODE_PMTUD_SILENT_TTL;
}
else
{
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
}
}
return 0;
}
static int timeout_pmtud_silent_TTL(scamper_task_t *task)
{
trace_state_t *state = task->state;
/*
* select another TTL to probe with, if possible. if not, then
* the search halts and we move on
*/
if(pmtud_TTL_set_probettl(task, state->TTL->lower, state->ttl) == 0)
{
/* finish this portion of the TTL limited search */
pmtud_L2_search_end(task);
}
return 0;
}
/*
* timeout_pmtud_badsugg
*
* if we timeout while trying to determine the underlying MTU on a path
* where a router gives a bad suggestion, chances are that an ICMP blackhole
* exists later in the path. try sending a larger packet, if we can.
*/
static int timeout_pmtud_badsugg(scamper_task_t *task)
{
trace_state_t *state = task->state;
int lower, upper;
lower = state->header_size + state->payload_size;
upper = state->L2->upper;
pmtud_L2_hop(state, NULL);
if(lower + 1 != upper)
{
pmtud_L2_set_probesize(state, lower, upper);
}
else
{
/* terminate the search now */
state->L2->lower = state->L2->out = lower;
state->L2->upper = upper;
/* if the pmtud is completed, then move on */
if(pmtud_L2_search_end(task) == 1)
{
return 0;
}
}
return 0;
}
static int timeout_rtsock(scamper_task_t *task)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
/*
* if we can't get sense out of the route socket, then do the trace
* anyway, but without pmtud or datalink support
*/
trace->flags &= ~(SCAMPER_TRACE_FLAG_PMTUD | SCAMPER_TRACE_FLAG_DL);
state->mode = MODE_TRACE;
return 0;
}
/*
* do_trace_handle_timeout
*
* the trace has expired while sitting on the wait queue.
* handle this event appropriately.
*/
static int do_trace_handle_timeout(scamper_task_t *task)
{
static int (* const func[])(scamper_task_t *) = {
timeout_trace, /* MODE_TRACE == 0x00 */
timeout_lastditch, /* MODE_LASTDITCH == 0x01 */
timeout_pmtud_default, /* MODE_PMTUD_DEFAULT == 0x02 */
timeout_pmtud_silent_L2, /* MODE_PMTUD_SILENT_L2 == 0x03 */
timeout_pmtud_silent_TTL, /* MODE_PMTUD_SILENT_TTL == 0x04 */
timeout_pmtud_badsugg, /* MODE_PMTUD_BADSUGG == 0x05 */
timeout_rtsock, /* MODE_RTSOCK == 0x06 */
};
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
assert(state->mode <= MODE_MAX);
/*
* if we have sent all alloted attempts for this probe type, then
* handle this particular probe failing
*/
if(state->attempt == trace->attempts)
{
/* we're probably going to send another probe, so reset the attempt # */
state->attempt = 0;
/* call the function that handles a timeout in this particular mode */
func[state->mode](task);
}
return 0;
}
static int handletcp_trace(scamper_task_t *task, scamper_dl_rec_t *dl,
trace_probe_t *probe)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_trace_hop_t *hop;
/* we should only have to deal with probes sent while in the trace state */
if(probe->mode != MODE_TRACE)
{
return 0;
}
/* create a hop record based off the TCP data */
if((hop = trace_tcp_hop(probe, dl)) == NULL)
{
return -1;
}
trace_hopins(&trace->hops[hop->hop_probe_ttl-1], hop);
/* record the receive timestamp with the probe structure */
if((probe->flags & TRACE_PROBE_FLAG_DL_RX) != 0 &&
(dl->dl_flags & SCAMPER_DL_FLAG_TIMESTAMP) != 0)
{
timeval_cpy(&probe->rx_tv, &dl->dl_tv);
probe->flags |= TRACE_PROBE_FLAG_DL_RX;
}
probe->rx++;
/* if the reply is for the current working hop */
if(hop->hop_probe_ttl - 1 == trace->hop_count)
{
/* if we are sending all allotted probes to the target */
if(trace->flags & SCAMPER_TRACE_FLAG_ALLATTEMPTS)
{
/*
* if we get an out of order reply, then we go back to waiting for
* the one we just probed for
*/
if(probe->id + 1 != state->attempt)
{
return 0;
}
if(state->attempt < trace->attempts)
{
scamper_queue_probe(task->queue);
}
}
else
{
trace->hop_count++;
trace_stop_completed(trace);
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
}
}
else
{
trace_stop_completed(trace);
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
}
return 0;
}
static int handletcp_lastditch(scamper_task_t *task, scamper_dl_rec_t *dl,
trace_probe_t *probe)
{
scamper_trace_t *trace = task->data;
scamper_trace_hop_t *hop;
/* only handle TCP responses in these two states */
if(probe->mode != MODE_TRACE && probe->mode != MODE_LASTDITCH)
{
return 0;
}
probe->rx++;
/* create a hop record based off the TCP data */
if((hop = trace_tcp_hop(probe, dl)) == NULL)
{
return -1;
}
if(probe->mode == MODE_LASTDITCH)
{
trace_hopins(&trace->lastditch, hop);
trace_stop_gaplimit((scamper_trace_t *)task->data);
scamper_queue_done(task->queue, scamper_holdtime_get()*1000);
}
else
{
/*
* XXX: after inserting the hop, probably should go back into the trace
* mode
*/
trace_hopins(&trace->hops[hop->hop_probe_ttl-1], hop);
}
return 0;
}
/*
* dlin_trace
*
* handle a datalink record for an inbound packet which was sent
* for a probe in the trace state.
*
* in this case, we use the timestamp and the ethernet mac address
* [if available] to update the hop record.
*/
static void dlin_trace(scamper_trace_t *trace,
scamper_dl_rec_t *dl, trace_probe_t *probe)
{
scamper_trace_hop_t *hop;
struct timeval tv;
/* adjust the rtt based on the timestamp included in the datalink record */
timeval_rtt(&tv, &probe->tx_tv, &probe->rx_tv);
for(hop=trace->hops[probe->ttl-1]; hop != NULL; hop = hop->hop_next)
{
if(probe->id + 1 < hop->hop_probe_id) continue;
if(probe->id + 1 > hop->hop_probe_id) break;
scamper_debug(__func__,
"hop %d.%06d dl_rec %d.%06d diff %lld",
hop->hop_rtt.tv_sec, hop->hop_rtt.tv_usec,
tv.tv_sec, tv.tv_usec,
timeval_diff_usec(&hop->hop_rtt, &tv));
hop->hop_flags &= ~(SCAMPER_TRACE_HOP_FLAG_TS_SOCK_RX);
hop->hop_flags |= SCAMPER_TRACE_HOP_FLAG_TS_DL_RX;
timeval_cpy(&hop->hop_rtt, &tv);
}
return;
}
static void dlout_apply(scamper_trace_hop_t *hop,
trace_probe_t *probe, struct timeval *diff)
{
while(hop != NULL)
{
if(probe->id + 1 > hop->hop_probe_id)
{
break;
}
if(probe->id + 1 == hop->hop_probe_id)
{
hop->hop_flags |= SCAMPER_TRACE_HOP_FLAG_TS_DL_TX;
timeval_add_tv(&hop->hop_rtt, diff);
}
hop = hop->hop_next;
}
return;
}
/*
* dlout_trace
*
* adjust the RTT recorded for a probe/reply sequence based on an updated
* transmit timestamp corresponding to when the packet was queued at the
* network interface.
*/
static void dlout_trace(scamper_trace_t *trace,
trace_probe_t *probe, struct timeval *diff)
{
dlout_apply(trace->hops[probe->ttl-1], probe, diff);
return;
}
/*
* dlout_lastditch
*
*/
static void dlout_lastditch(scamper_trace_t *trace,
trace_probe_t *probe, struct timeval *diff)
{
dlout_apply(trace->lastditch, probe, diff);
return;
}
/*
* do_trace_handle_dl
*
* handle a datalink record that may have something useful for the
* traceroute, such as a more accurate timestamp or a mac address of
* the host that delivered the response to us.
*/
static int do_trace_handle_dl(scamper_task_t *task, scamper_dl_rec_t *dl)
{
static void (* const dlout_func[])(scamper_trace_t *, trace_probe_t *,
struct timeval *) =
{
dlout_trace, /* MODE_TRACE == 0x00 */
dlout_lastditch, /* MODE_LASTDITCH == 0x01 */
NULL, /* MODE_PMTUD_DEFAULT == 0x02 */
NULL, /* MODE_PMTUD_SILENT_L2 == 0x03 */
NULL, /* MODE_PMTUD_SILENT_TTL == 0x04 */
NULL, /* MODE_PMTUD_BADSUGG == 0x05 */
NULL, /* MODE_RTSOCK == 0x06 */
};
static void (* const dlin_func[])(scamper_trace_t *, scamper_dl_rec_t *,
trace_probe_t *) =
{
dlin_trace, /* MODE_TRACE == 0x00 */
NULL, /* MODE_LASTDITCH == 0x01 */
NULL, /* MODE_PMTUD_DEFAULT == 0x02 */
NULL, /* MODE_PMTUD_SILENT_L2 == 0x03 */
NULL, /* MODE_PMTUD_SILENT_TTL == 0x04 */
NULL, /* MODE_PMTUD_BADSUGG == 0x05 */
NULL, /* MODE_RTSOCK == 0x06 */
};
static int (* const handletcp_func[])(scamper_task_t *, scamper_dl_rec_t *,
trace_probe_t *) =
{
handletcp_trace, /* MODE_TRACE == 0x00 */
handletcp_lastditch, /* MODE_LASTDITCH == 0x01 */
NULL, /* MODE_PMTUD_DEFAULT == 0x02 */
NULL, /* MODE_PMTUD_SILENT_L2 == 0x03 */
NULL, /* MODE_PMTUD_SILENT_TTL == 0x04 */
NULL, /* MODE_PMTUD_BADSUGG == 0x05 */
NULL, /* MODE_RTSOCK == 0x06 */
};
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
trace_probe_t *probe;
uint16_t probe_id;
int direction;
struct timeval diff;
/* if this record has no timestamp, go no further */
if((dl->dl_flags & SCAMPER_DL_FLAG_TIMESTAMP) == 0)
{
return 0;
}
/*
* try and determine the direction of the packet and the associated probe
* for this datalink record
*/
if(trace->type == SCAMPER_TRACE_TYPE_UDP ||
trace->type == SCAMPER_TRACE_TYPE_UDP_PARIS)
{
if(dl->dl_ip_proto == IPPROTO_UDP)
{
if(dl->dl_udp_sport != trace->sport) return 0;
direction = 1;
if(trace->type == SCAMPER_TRACE_TYPE_UDP)
{
probe_id = dl->dl_udp_dport - trace->dport;
}
else
{
probe_id = ntohs(dl->dl_udp_sum) - 1;
}
}
else if(SCAMPER_DL_IS_ICMP(dl))
{
if(SCAMPER_DL_IS_ICMP_TTL_EXP(dl) == 0 &&
SCAMPER_DL_IS_ICMP_UNREACH(dl) == 0 &&
SCAMPER_DL_IS_ICMP_PACKET_TOO_BIG(dl) == 0)
{
return 0;
}
if(dl->dl_icmp_ip_proto != IPPROTO_UDP) return 0;
if(dl->dl_icmp_udp_sport != trace->sport) return 0;
direction = 0;
if(trace->type == SCAMPER_TRACE_TYPE_UDP)
{
probe_id = dl->dl_icmp_udp_dport - trace->dport;
}
else
{
if(dl->dl_icmp_udp_dport != trace->dport)
{
return 0;
}
if(dl->dl_af == AF_INET)
{
if(dl->dl_icmp_udp_sum == dl->dl_icmp_ip_id &&
dl->dl_icmp_udp_sum != 0)
{
probe_id = ntohs(dl->dl_icmp_udp_sum) - 1;
}
else if(trace_ipid_fudge(state,dl->dl_icmp_ip_id,
&probe_id) != 0)
{
return 0;
}
}
else
{
assert(dl->dl_af == AF_INET6);
if(dl->dl_icmp_udp_sum == 0)
{
return 0;
}
probe_id = ntohs(dl->dl_icmp_udp_sum) - 1;
}
}
}
else return 0;
}
else if(trace->type == SCAMPER_TRACE_TYPE_ICMP_ECHO ||
trace->type == SCAMPER_TRACE_TYPE_ICMP_ECHO_PARIS)
{
if(SCAMPER_DL_IS_ICMP(dl) == 0) return 0;
if(SCAMPER_DL_IS_ICMP_ECHO_REQUEST(dl))
{
if(dl->dl_icmp_id != trace->sport) return 0;
probe_id = dl->dl_icmp_seq;
direction = 1;
}
else if(SCAMPER_DL_IS_ICMP_ECHO_REPLY(dl))
{
if(dl->dl_icmp_id != trace->sport) return 0;
probe_id = dl->dl_icmp_seq;
direction = 0;
}
else if((SCAMPER_DL_IS_ICMP_TTL_EXP(dl) ||
SCAMPER_DL_IS_ICMP_UNREACH(dl) ||
SCAMPER_DL_IS_ICMP_PACKET_TOO_BIG(dl)) &&
SCAMPER_DL_IS_ICMP_PROTO_ICMP_ECHO_REQ(dl))
{
if(dl->dl_icmp_icmp_id != trace->sport) return 0;
probe_id = dl->dl_icmp_icmp_seq;
direction = 0;
}
else return 0;
}
else if(trace->type == SCAMPER_TRACE_TYPE_TCP)
{
if(dl->dl_ip_proto == IPPROTO_TCP)
{
/*
* if the syn flag (and only the syn flag is set) and the sport
* and dport match what we probe with, then the probe is probably
* an outgoing one.
*/
if((dl->dl_tcp_flags & TH_SYN) == TH_SYN &&
(dl->dl_tcp_flags & ~TH_SYN) == 0 &&
dl->dl_tcp_sport == trace->sport)
{
if(dl->dl_af == AF_INET)
probe_id = dl->dl_ip_id - 1;
else
probe_id = dl->dl_ip_flow - 1;
direction = 1;
}
else if(dl->dl_tcp_sport == trace->dport &&
dl->dl_tcp_dport == trace->sport)
{
probe_id = state->id_next - 1;
direction = 0;
}
else return 0;
}
else if(SCAMPER_DL_IS_ICMP(dl))
{
if(SCAMPER_DL_IS_ICMP_TTL_EXP(dl) == 0 &&
SCAMPER_DL_IS_ICMP_UNREACH(dl) == 0 &&
SCAMPER_DL_IS_ICMP_PACKET_TOO_BIG(dl) == 0)
{
return 0;
}
if(dl->dl_icmp_ip_proto != IPPROTO_TCP) return 0;
if(dl->dl_icmp_tcp_sport != trace->sport) return 0;
if(dl->dl_icmp_tcp_dport != trace->dport) return 0;
/* determine which probe the ICMP response corresponds to */
if(dl->dl_af == AF_INET)
{
if(trace_ipid_fudge(state, dl->dl_icmp_ip_id, &probe_id) != 0)
{
return 0;
}
}
else
{
if(dl->dl_icmp_ip_flow == 0) return 0;
probe_id = dl->dl_icmp_ip_flow - 1;
}
direction = 0;
}
else return 0;
}
else return 0;
/* find the probe that corresponds to this datalink record */
if(probe_id >= state->id_next)
{
return 0;
}
probe = state->probes[probe_id];
/* make sure the probe structure makes sense */
assert(probe->mode <= MODE_MAX);
/* if this is an inbound packet with a timestamp attached */
if(direction == 0)
{
/* inbound TCP packets result in a hop record being created */
if(dl->dl_ip_proto == IPPROTO_TCP)
{
/*
* record the receive timestamp with the probe structure if it hasn't
* been previously recorded
*/
if((probe->flags & TRACE_PROBE_FLAG_DL_RX) != 0)
{
timeval_cpy(&probe->rx_tv, &dl->dl_tv);
probe->flags |= TRACE_PROBE_FLAG_DL_RX;
}
if(handletcp_func[probe->mode] != NULL)
{
handletcp_func[probe->mode](task, dl, probe);
}
}
/* other datalink records result in timestamps being adjusted */
else if((probe->flags & TRACE_PROBE_FLAG_DL_RX) == 0)
{
/* update the receive timestamp stored with the probe */
probe->flags |= TRACE_PROBE_FLAG_DL_RX;
timeval_cpy(&probe->rx_tv, &dl->dl_tv);
/* if at least one hop record is present then adjust */
if(probe->rx > 0 && dlin_func[probe->mode] != NULL)
{
dlin_func[probe->mode](trace, dl, probe);
}
}
}
else
{
scamper_debug(__func__, "probe %d.%06d dl_rec %d.%06d diff %lld",
probe->tx_tv.tv_sec, probe->tx_tv.tv_usec,
dl->dl_tv.tv_sec, dl->dl_tv.tv_usec,
timeval_diff_usec(&probe->tx_tv, &dl->dl_tv));
/* if at least one hop record is present then adjust */
if(probe->rx > 0 && dlout_func[probe->mode] != NULL)
{
timeval_rtt(&diff, &probe->tx_tv, &dl->dl_tv);
dlout_func[probe->mode](trace, probe, &diff);
}
/* update the TX timestamp of the probe */
probe->flags |= TRACE_PROBE_FLAG_DL_TX;
timeval_cpy(&probe->tx_tv, &dl->dl_tv);
}
return 0;
}
static int rt_framing(scamper_task_t *task, scamper_rt_rec_t *rt)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
scamper_dl_t *dl = scamper_fd_write_state(state->dl);
int af, tx_type;
/*
* determine the header to append when sending packets on the datalink.
* if the datalink code cannot send packets, then we can't do PMTUD
*/
tx_type = scamper_dl_tx_type(dl);
/*
* determine the size of the header to prepend to the packet to put it
* on the datalink
*/
switch(tx_type)
{
case SCAMPER_DL_TX_UNSUPPORTED:
return -1;
case SCAMPER_DL_TX_ETHERNET:
case SCAMPER_DL_TX_ETHLOOP:
state->dl_size = 14;
break;
case SCAMPER_DL_TX_NULL:
state->dl_size = sizeof(int);
break;
case SCAMPER_DL_TX_RAW:
state->dl_size = 0;
return 0;
default:
scamper_debug(__func__, "unhandled tx_type %d", tx_type);
return -1;
}
/* allocate the header */
if((state->dl_hdr = malloc(state->dl_size)) == NULL)
{
printerror(errno, strerror, __func__, "could not malloc dl_hdr");
return -1;
}
if(tx_type == SCAMPER_DL_TX_ETHERNET)
{
/*
* allocate a datalink header to use, and determine the source mac
* address to use
*/
if(if_getmac(rt->ifindex, state->dl_hdr+6) == -1)
{
scamper_debug(__func__, "could not get source mac");
return -1;
}
/*
* determine the destination mac address (the target).
*/
if(rt->gwaddr == NULL)
{
/* no gateway address means destination is on local network */
memcpy(state->dl_hdr, state->dl_hdr+6, 6);
if(scamper_addr2mac_whohas(rt->ifindex, trace->src, trace->dst,
state->dl_hdr) != 1)
{
scamper_debug(__func__, "could not get destination mac");
return -1;
}
}
else if(rt->gwaddr->type == SCAMPER_ADDR_TYPE_ETHERNET)
{
/* the gateway mac address was provided by the route socket */
memcpy(state->dl_hdr, rt->gwaddr->addr, 6);
}
else
{
/* the gateway address was returned as an IP */
memcpy(state->dl_hdr, state->dl_hdr+6, 6);
if(scamper_addr2mac_whohas(rt->ifindex, trace->src, rt->gwaddr,
state->dl_hdr) != 1)
{
scamper_debug(__func__, "could not get gateway mac");
return -1;
}
}
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
{
state->dl_hdr[12] = 0x08;
state->dl_hdr[13] = 0x00;
}
else if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV6)
{
state->dl_hdr[12] = 0x86;
state->dl_hdr[13] = 0xDD;
}
else return -1;
}
else if(tx_type == SCAMPER_DL_TX_NULL)
{
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
{
af = AF_INET;
}
else if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV6)
{
af = AF_INET6;
}
else return -1;
memcpy(state->dl_hdr, &af, sizeof(int));
}
else if(tx_type == SCAMPER_DL_TX_ETHLOOP)
{
memset(state->dl_hdr, 0, 12);
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
{
state->dl_hdr[12] = 0x08;
state->dl_hdr[13] = 0x00;
}
else if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV6)
{
state->dl_hdr[12] = 0x86;
state->dl_hdr[13] = 0xDD;
}
else return -1;
}
else return -1;
return 0;
}
static int do_trace_handle_rt(scamper_task_t *task, scamper_rt_rec_t *rt)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
if(state->mode != MODE_RTSOCK)
{
return 0;
}
/* if there was a problem getting the ifindex, handle that */
if(rt->error != 0 || rt->ifindex < 0)
{
printerror(errno, strerror, __func__, "could not get ifindex");
goto err;
}
/*
* if scamper is supposed to get tx timestamps from the datalink, or
* scamper needs the datalink to transmit packets, then try and get a
* datalink on the ifindex specified.
*/
if((state->dl = scamper_fd_dl(rt->ifindex)) == NULL)
{
scamper_debug(__func__, "could not get dl for %d", rt->ifindex);
goto err;
}
/*
* if we're doing path MTU discovery debugging, or doing tcp traceroute,
* or doing udp paris traceroute, determine the underlying framing to use
* with each probe packet that will be sent on the datalink.
*/
if((trace->flags & SCAMPER_TRACE_FLAG_PMTUD) != 0 ||
trace->type == SCAMPER_TRACE_TYPE_TCP ||
trace->type == SCAMPER_TRACE_TYPE_UDP_PARIS)
{
if(rt_framing(task, rt) != 0)
{
goto err;
}
}
done:
state->mode = MODE_TRACE;
state->attempt = 0;
scamper_queue_probe(task->queue);
return 0;
err:
if(trace->type == SCAMPER_TRACE_TYPE_TCP ||
trace->type == SCAMPER_TRACE_TYPE_UDP_PARIS)
{
goto harderr;
}
trace->flags &= ~(SCAMPER_TRACE_FLAG_PMTUD | SCAMPER_TRACE_FLAG_DL);
goto done;
harderr:
trace_handleerror(task, errno);
return -1;
}
static int do_trace_write(scamper_task_t *task)
{
scamper_outfile_t *outfile = scamper_source_getoutfile(task->source);
scamper_file_t *sf = scamper_outfile_getfile(outfile);
scamper_file_write_trace(sf, (scamper_trace_t *)task->data);
return 0;
}
static void trace_state_free(trace_state_t *state)
{
trace_probe_t *probe;
int i;
/* free the probe records scamper kept */
if(state->probes != NULL)
{
for(i=0; i<state->id_next; i++)
{
probe = state->probes[i];
if(probe->rx_mac != NULL)
{
scamper_addr_free(probe->rx_mac);
}
free(probe);
}
free(state->probes);
}
if(state->dl != NULL) scamper_fd_free(state->dl);
if(state->icmp != NULL) scamper_fd_free(state->icmp);
if(state->probe != NULL) scamper_fd_free(state->probe);
if(state->route != NULL) scamper_fd_free(state->route);
if(state->dl_hdr != NULL) free(state->dl_hdr);
free(state);
return;
}
static int trace_state_alloc(scamper_task_t *task)
{
scamper_trace_t *trace = task->data;
trace_state_t *state;
int id_max;
assert(trace != NULL);
/* allocate struct to keep state while processing the trace */
if((state = malloc_zero(sizeof(trace_state_t))) == NULL)
{
goto err;
}
/* allocate memory to record hops */
state->alloc_hops = TRACE_ALLOC_HOPS;
if(trace->firsthop >= state->alloc_hops)
{
if(state->alloc_hops + (uint16_t)trace->firsthop > 256)
{
state->alloc_hops = 256;
}
else
{
state->alloc_hops += trace->firsthop;
}
}
if(scamper_trace_hops_alloc(trace, state->alloc_hops) == -1)
{
goto err;
}
/* allocate enough ids to probe each hop with max number of attempts */
id_max = (state->alloc_hops - trace->firsthop + 2) * trace->attempts;
/* allocate enough space to store state for each probe */
if((state->probes = malloc(sizeof(trace_probe_t *) * id_max)) == NULL)
{
goto err;
}
/* if scamper has to get the ifindex, then start in the rtsock mode */
if((trace->flags & (SCAMPER_TRACE_FLAG_PMTUD|SCAMPER_TRACE_FLAG_DL)) != 0 ||
trace->type == SCAMPER_TRACE_TYPE_TCP ||
trace->type == SCAMPER_TRACE_TYPE_UDP_PARIS)
{
state->mode = MODE_RTSOCK;
if((state->route = scamper_fd_rtsock()) == NULL)
{
goto err;
}
}
else
{
state->mode = MODE_TRACE;
}
state->dl = NULL;
state->dl_hdr = NULL;
state->dl_size = 0;
state->ttl = trace->firsthop;
state->attempt = 0;
state->header_size = scamper_trace_probe_headerlen(trace);
state->payload_size = trace->probe_size - state->header_size;
state->id_next = 0;
state->id_max = id_max;
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
{
state->icmp = scamper_fd_icmp4();
}
else if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV6)
{
state->icmp = scamper_fd_icmp6();
}
else goto err;
switch(trace->type)
{
case SCAMPER_TRACE_TYPE_TCP:
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
state->probe = scamper_fd_tcp4(scamper_sport_get());
else
state->probe = scamper_fd_tcp6(scamper_sport_get());
break;
case SCAMPER_TRACE_TYPE_ICMP_ECHO:
case SCAMPER_TRACE_TYPE_ICMP_ECHO_PARIS:
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
state->probe = scamper_fd_icmp4();
else
state->probe = scamper_fd_icmp6();
break;
case SCAMPER_TRACE_TYPE_UDP:
case SCAMPER_TRACE_TYPE_UDP_PARIS:
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
state->probe = scamper_fd_udp4(scamper_sport_get());
else
state->probe = scamper_fd_udp6(scamper_sport_get());
break;
}
if(state->icmp == NULL || state->probe == NULL)
{
goto err;
}
task->state = state;
return 0;
err:
if(state != NULL) trace_state_free(state);
return -1;
}
static void do_trace_free(scamper_task_t *task)
{
scamper_trace_t *trace;
trace_state_t *state;
/* free any state kept */
if((state = task->state) != NULL)
{
trace_state_free(state);
}
/* free any trace data collected */
if((trace = task->data) != NULL)
{
scamper_trace_free(trace);
}
return;
}
/*
* do_trace_probe
*
* time to probe, so send the packet.
*/
static int do_trace_probe(scamper_task_t *task)
{
scamper_trace_t *trace = task->data;
trace_state_t *state = task->state;
trace_probe_t *tp = NULL;
scamper_probe_t probe;
uint16_t u16, i;
trace_probe_t **probes;
uint8_t *buf;
assert(trace != NULL);
if(state != NULL)
{
assert(state->attempt < trace->attempts);
assert(state->id_next <= state->id_max);
assert(state->alloc_hops > 0);
assert(state->alloc_hops <= 256);
assert(state->ttl != 0);
}
else
{
/* timestamp when the trace began */
gettimeofday_wrap(&trace->start);
/* determine the source address used for sending probes */
if((trace->src = scamper_getsrc(trace->dst)) == NULL)
{
trace_handleerror(task, errno);
return -1;
}
/* allocate state and store it with the task */
if(trace_state_alloc(task) != 0)
{
trace_handleerror(task, errno);
return -1;
}
state = task->state;
}
/* allocate some more space in the trace to store replies, if necessary */
if(state->alloc_hops == trace->hop_count)
{
/*
* figure out exactly how many hops should be allocated in the
* trace structure
*/
if(256 - state->alloc_hops <= TRACE_ALLOC_HOPS)
{
u16 = state->alloc_hops + TRACE_ALLOC_HOPS;
}
else
{
u16 = 256;
}
/* allocate the new hops */
if(scamper_trace_hops_alloc(trace, u16) != 0)
{
printerror(errno, strerror, __func__, "could not realloc hops");
trace_handleerror(task, errno);
return -1;
}
/* initialise the new hops to have null pointers */
for(i=state->alloc_hops; i<u16; i++)
{
trace->hops[i] = NULL;
}
state->alloc_hops = u16;
}
/* allocate some more space to store probes, if necessary */
if(state->id_next == state->id_max)
{
u16 = state->id_max + TRACE_ALLOC_HOPS;
probes = realloc(state->probes, sizeof(trace_probe_t *) * u16);
if(probes == NULL)
{
printerror(errno, strerror, __func__, "could not realloc");
trace_handleerror(task, errno);
return -1;
}
state->id_max = u16;
state->probes = probes;
}
if(state->mode == MODE_RTSOCK)
{
if(scamper_rtsock_getroute(state->route, trace->dst) != 0)
{
trace->flags &= ~(SCAMPER_TRACE_FLAG_PMTUD | SCAMPER_TRACE_FLAG_DL);
state->mode = MODE_TRACE;
state->attempt = 0;
}
else
{
state->attempt++;
scamper_queue_wait(task->queue, trace->wait * 1000);
return 0;
}
}
/* allocate a larger global pktbuf if needed */
if(pktbuf_len < state->payload_size)
{
if((buf = realloc(pktbuf, state->payload_size)) == NULL)
{
printerror(errno, strerror, __func__, "could not realloc");
trace_handleerror(task, errno);
return -1;
}
pktbuf = buf;
pktbuf_len = state->payload_size;
memset(pktbuf, 0, pktbuf_len);
}
probe.pr_ip_src = trace->src;
probe.pr_ip_dst = trace->dst;
probe.pr_ip_tos = trace->tos;
probe.pr_ip_ttl = state->ttl;
probe.pr_ip_id = 0;
probe.pr_ip_flow = 0;
probe.pr_data = pktbuf;
probe.pr_len = state->payload_size;
probe.pr_ipoptc = 0;
probe.pr_ipopts = NULL;
probe.pr_fd = scamper_fd_fd_get(state->probe);
if((state->mode == MODE_PMTUD_DEFAULT ||
state->mode == MODE_PMTUD_SILENT_L2 ||
state->mode == MODE_PMTUD_SILENT_TTL ||
state->mode == MODE_PMTUD_BADSUGG ||
trace->type == SCAMPER_TRACE_TYPE_TCP ||
trace->type == SCAMPER_TRACE_TYPE_UDP_PARIS) &&
state->dl != NULL)
{
probe.pr_dl = scamper_fd_write_state(state->dl);
probe.pr_dl_hdr = state->dl_hdr;
probe.pr_dl_size = state->dl_size;
}
else
{
probe.pr_dl = NULL;
probe.pr_dl_hdr = NULL;
probe.pr_dl_size = 0;
}
if(trace->type == SCAMPER_TRACE_TYPE_UDP ||
trace->type == SCAMPER_TRACE_TYPE_UDP_PARIS)
{
probe.pr_ip_proto = IPPROTO_UDP;
probe.pr_udp_sport = trace->sport;
probe.pr_udp_dport = trace->dport;
/*
* traditional traceroute identifies probes by varying the UDP
* destination port number. UDP-based paris traceroute identifies
* probes by varying the UDP checksum -- accomplished by manipulating
* the payload of the packet to get sequential values for the checksum
*/
if(trace->type == SCAMPER_TRACE_TYPE_UDP)
{
probe.pr_udp_dport += state->id_next;
}
else
{
/*
* hack the checksum to be our id field by setting the checksum
* id we want into the packet's body, then calculate the checksum
* across the packet, and then set the packet's body to be the
* value returned for the checksum. this effectively swaps two
* 16 bit quantities in the packet
*/
u16 = htons(state->id_next + 1);
memcpy(probe.pr_data, &u16, 2);
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
{
/*
* while the paris traceroute paper says that the payload of the
* packet is set so that the checksum field can be used to
* identify a returned probe, the paris traceroute code uses the
* IP ID field.
* this is presumably because FreeBSD systems seem to reset the
* UDP checksum quoted in ICMP destination unreachable messages.
* scamper's paris traceroute implementation used both IP ID and
* UDP checksum.
*/
probe.pr_ip_id = state->id_next + 1;
u16 = scamper_udp4_cksum(&probe);
}
else
{
u16 = scamper_udp6_cksum(&probe);
}
memcpy(probe.pr_data, &u16, 2);
}
}
else if(trace->type == SCAMPER_TRACE_TYPE_ICMP_ECHO ||
trace->type == SCAMPER_TRACE_TYPE_ICMP_ECHO_PARIS)
{
switch(trace->dst->type)
{
case SCAMPER_ADDR_TYPE_IPV4:
probe.pr_ip_proto = IPPROTO_ICMP;
probe.pr_icmp_type = ICMP_ECHO;
break;
case SCAMPER_ADDR_TYPE_IPV6:
probe.pr_ip_proto = IPPROTO_ICMPV6;
probe.pr_icmp_type = ICMP6_ECHO_REQUEST;
break;
}
probe.pr_icmp_code = 0;
probe.pr_icmp_id = trace->sport;
probe.pr_icmp_seq = state->id_next;
/*
* ICMP-based paris traceroute tries to ensure the same path is taken
* through a load balancer by sending all probes with a constant value
* for the checksum. manipulate the payload so this happens.
* the value chosen to seed the checksum is the trace->sport value, but
* it could really be anything.
*/
if(trace->type == SCAMPER_TRACE_TYPE_ICMP_ECHO_PARIS)
{
memcpy(probe.pr_data, &trace->sport, 2);
switch(trace->dst->type)
{
case SCAMPER_ADDR_TYPE_IPV4:
u16 = scamper_icmp4_cksum(&probe);
break;
case SCAMPER_ADDR_TYPE_IPV6:
u16 = scamper_icmp6_cksum(&probe);
break;
}
memcpy(probe.pr_data, &u16, 2);
}
}
else if(trace->type == SCAMPER_TRACE_TYPE_TCP)
{
probe.pr_ip_proto = IPPROTO_TCP;
probe.pr_tcp_sport = trace->sport;
probe.pr_tcp_dport = trace->dport;
probe.pr_tcp_seq = 0;
probe.pr_tcp_ack = 0;
probe.pr_tcp_flags = TH_SYN;
probe.pr_tcp_win = 0;
if(trace->dst->type == SCAMPER_ADDR_TYPE_IPV4)
probe.pr_ip_id = state->id_next + 1;
else
probe.pr_ip_flow = state->id_next + 1;
}
else return -1;
/*
* allocate a trace probe state record before we try and send the probe
* as there is no point sending something into the wild that we can't
* record
*/
if((tp = malloc_zero(sizeof(trace_probe_t))) == NULL)
{
trace_handleerror(task, errno);
return -1;
}
/* send the probe */
if(scamper_probe(&probe) == -1)
{
free(tp);
trace_handleerror(task, probe.pr_errno);
return -1;
}
timeval_cpy(&tp->tx_tv, &probe.pr_tx);
tp->ttl = probe.pr_ip_ttl;
tp->size = probe.pr_len + state->header_size;
tp->mode = state->mode;
tp->id = state->attempt;
state->probes[state->id_next] = tp;
state->id_next++;
state->attempt++;
scamper_queue_wait(task->queue, trace->wait * 1000);
return 0;
}
/*
* scamper_do_trace_alloc
*
* given a string representing a traceroute task, parse the parameters and
* assemble a trace. return the trace structure so that it is all ready to
* go.
*/
scamper_trace_t *scamper_do_trace_alloc(char *str)
{
/* default values of various trace parameters */
uint8_t type = SCAMPER_TRACE_TYPE_UDP;
uint8_t flags = 0;
uint8_t attempts = SCAMPER_DO_TRACE_ATTEMPTS_DEF;
uint8_t firsthop = SCAMPER_DO_TRACE_FIRSTHOP_DEF;
uint8_t gaplimit = SCAMPER_DO_TRACE_GAPLIMIT_DEF;
uint8_t gapaction = SCAMPER_DO_TRACE_GAPACTION_DEF;
uint8_t hoplimit = SCAMPER_DO_TRACE_HOPLIMIT_DEF;
uint8_t tos = SCAMPER_DO_TRACE_TOS_DEF;
uint8_t wait = SCAMPER_DO_TRACE_WAIT_DEF;
uint8_t loops = SCAMPER_DO_TRACE_LOOPS_DEF;
uint8_t loopaction = SCAMPER_DO_TRACE_LOOPACTION_DEF;
uint16_t sport = scamper_sport_get();
uint16_t dport = SCAMPER_DO_TRACE_DPORT_DEF;
scamper_option_out_t *opts_out = NULL, *opt;
scamper_trace_t *trace = NULL;
char *addr;
long tmp;
/* try and parse the string passed in */
if(scamper_options_parse(str, trace_opts_in, trace_opts_cnt,
&opts_out, &addr) != 0)
{
goto err;
}
/* if there is no IP address after the options string, then stop now */
if(addr == NULL)
{
goto err;
}
/* parse the options, do preliminary sanity checks */
for(opt = opts_out; opt != NULL; opt = opt->next)
{
switch(opt->id)
{
case TRACE_OPT_DPORT:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_DPORT_MIN ||
tmp > SCAMPER_DO_TRACE_DPORT_MAX)
{
goto err;
}
dport = tmp;
break;
case TRACE_OPT_FIRSTHOP:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_FIRSTHOP_MIN ||
tmp > SCAMPER_DO_TRACE_FIRSTHOP_MAX)
{
goto err;
}
firsthop = tmp;
break;
case TRACE_OPT_GAPLIMIT:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_GAPLIMIT_MIN ||
tmp > SCAMPER_DO_TRACE_GAPLIMIT_MAX)
{
goto err;
}
gaplimit = tmp;
break;
case TRACE_OPT_GAPACTION:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_GAPACTION_MIN ||
tmp > SCAMPER_DO_TRACE_GAPACTION_MAX)
{
goto err;
}
gapaction = tmp;
break;
case TRACE_OPT_LOOPS:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_LOOPS_MIN ||
tmp > SCAMPER_DO_TRACE_LOOPS_MAX)
{
goto err;
}
loops = tmp;
break;
case TRACE_OPT_LOOPACTION:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_LOOPACTION_MIN ||
tmp > SCAMPER_DO_TRACE_LOOPACTION_MAX)
{
goto err;
}
loopaction = tmp;
break;
case TRACE_OPT_MAXTTL:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_HOPLIMIT_MIN ||
tmp > SCAMPER_DO_TRACE_HOPLIMIT_MAX)
{
goto err;
}
hoplimit = tmp;
break;
case TRACE_OPT_PMTUD:
flags |= SCAMPER_TRACE_FLAG_PMTUD;
break;
case TRACE_OPT_PROTOCOL:
if(strcasecmp(opt->str, "UDP") == 0)
type = SCAMPER_TRACE_TYPE_UDP;
else if(strcasecmp(opt->str, "TCP") == 0)
type = SCAMPER_TRACE_TYPE_TCP;
else if(strcasecmp(opt->str, "ICMP") == 0)
type = SCAMPER_TRACE_TYPE_ICMP_ECHO;
else if(strcasecmp(opt->str, "ICMP-paris") == 0)
type = SCAMPER_TRACE_TYPE_ICMP_ECHO_PARIS;
else if(strcasecmp(opt->str, "UDP-paris") == 0)
type = SCAMPER_TRACE_TYPE_UDP_PARIS;
else goto err;
break;
case TRACE_OPT_ATTEMPTS:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_ATTEMPTS_MIN ||
tmp > SCAMPER_DO_TRACE_ATTEMPTS_MAX)
{
goto err;
}
attempts = tmp;
break;
case TRACE_OPT_ALLATTEMPTS:
flags |= SCAMPER_TRACE_FLAG_ALLATTEMPTS;
break;
case TRACE_OPT_SPORT:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_SPORT_MIN ||
tmp > SCAMPER_DO_TRACE_SPORT_MAX)
{
goto err;
}
sport = tmp;
break;
case TRACE_OPT_TOS:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_TOS_MIN ||
tmp > SCAMPER_DO_TRACE_TOS_MAX)
{
goto err;
}
tos = tmp;
break;
case TRACE_OPT_WAIT:
if(string_tolong(opt->str, &tmp) == -1 ||
tmp < SCAMPER_DO_TRACE_WAIT_MIN ||
tmp > SCAMPER_DO_TRACE_WAIT_MAX)
{
goto err;
}
wait = tmp;
break;
}
}
scamper_options_free(opts_out); opts_out = NULL;
/* sanity check that we don't begin beyond our probe hoplimit */
if(firsthop > hoplimit && hoplimit != 0)
{
goto err;
}
/* can't really do pmtud properly without all of the path */
if(firsthop > 1 && (flags & SCAMPER_TRACE_FLAG_PMTUD))
{
goto err;
}
/* can't really do pmtud properly without a UDP traceroute method */
if((flags & SCAMPER_TRACE_FLAG_PMTUD) == 1 &&
type != SCAMPER_TRACE_TYPE_UDP && type != SCAMPER_TRACE_TYPE_UDP_PARIS)
{
goto err;
}
if((trace = scamper_trace_alloc()) == NULL)
{
goto err;
}
if((trace->dst= scamper_addrcache_resolve(addrcache,AF_UNSPEC,addr)) == NULL)
{
goto err;
}
trace->type = type;
trace->flags = flags;
trace->attempts = attempts;
trace->hoplimit = hoplimit;
trace->gaplimit = gaplimit;
trace->gapaction = gapaction;
trace->firsthop = firsthop;
trace->tos = tos;
trace->wait = wait;
trace->loops = loops;
trace->loopaction = loopaction;
trace->sport = sport;
trace->dport = dport;
switch(trace->dst->type)
{
case SCAMPER_ADDR_TYPE_IPV4:
if(trace->type == SCAMPER_TRACE_TYPE_TCP)
{
trace->probe_size = 40;
}
else
{
trace->probe_size = 44;
}
break;
case SCAMPER_ADDR_TYPE_IPV6:
trace->probe_size = 60;
break;
default:
goto err;
}
if(scamper_option_dl() != 0)
{
trace->flags |= SCAMPER_TRACE_FLAG_DL;
}
return trace;
err:
if(trace != NULL) scamper_trace_free(trace);
if(opts_out != NULL) scamper_options_free(opts_out);
return NULL;
}
scamper_task_t *scamper_do_trace_alloctask(scamper_trace_t *trace,
scamper_list_t *list,
scamper_cycle_t *cycle)
{
scamper_task_t *task;
/* associate the list and cycle with the trace */
trace->list = scamper_list_use(list);
trace->cycle = scamper_cycle_use(cycle);
/* allocate the task structure and store the trace with it */
if((task = scamper_task_alloc(trace->dst, &trace_funcs)) != NULL)
{
task->data = trace;
return task;
}
return NULL;
}
void scamper_do_trace_cleanup()
{
if(pktbuf != NULL)
{
free(pktbuf);
pktbuf = NULL;
}
if(if_sock != -1)
{
close(if_sock);
if_sock = -1;
}
return;
}
int scamper_do_trace_init()
{
if((if_sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
{
return -1;
}
trace_funcs.probe = do_trace_probe;
trace_funcs.handle_icmp = do_trace_handle_icmp;
trace_funcs.handle_dl = do_trace_handle_dl;
trace_funcs.handle_rt = do_trace_handle_rt;
trace_funcs.handle_timeout = do_trace_handle_timeout;
trace_funcs.write = do_trace_write;
trace_funcs.task_free = do_trace_free;
return 0;
}
|