aboutsummaryrefslogtreecommitdiffstats
path: root/src/vcl/vcl_locked.h
AgeCommit message (Expand)AuthorFilesLines
2019-01-29vls: multi-process and multi-threaded apps improvementsFlorin Coras1-0/+2
2019-01-07vcl/ldp: add locked sessions shim layerFlorin Coras1-0/+60
a> 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 
#!/usr/bin/env python
""" BFD tests """

from __future__ import division
import unittest
import hashlib
import binascii
import time
from struct import pack, unpack
from random import randint, shuffle, getrandbits
from socket import AF_INET, AF_INET6, inet_ntop
from scapy.packet import Raw
from scapy.layers.l2 import Ether
from scapy.layers.inet import UDP, IP
from scapy.layers.inet6 import IPv6
from bfd import VppBFDAuthKey, BFD, BFDAuthType, VppBFDUDPSession, \
    BFDDiagCode, BFDState, BFD_vpp_echo
from framework import VppTestCase, VppTestRunner, running_extended_tests
from vpp_pg_interface import CaptureTimeoutError
from util import ppp
from vpp_papi_provider import UnexpectedApiReturnValueError

USEC_IN_SEC = 1000000


class AuthKeyFactory(object):
    """Factory class for creating auth keys with unique conf key ID"""

    def __init__(self):
        self._conf_key_ids = {}

    def create_random_key(self, test, auth_type=BFDAuthType.keyed_sha1):
        """ create a random key with unique conf key id """
        conf_key_id = randint(0, 0xFFFFFFFF)
        while conf_key_id in self._conf_key_ids:
            conf_key_id = randint(0, 0xFFFFFFFF)
        self._conf_key_ids[conf_key_id] = 1
        key = str(bytearray([randint(0, 255) for _ in range(randint(1, 20))]))
        return VppBFDAuthKey(test=test, auth_type=auth_type,
                             conf_key_id=conf_key_id, key=key)


@unittest.skipUnless(running_extended_tests(), "part of extended tests")
class BFDAPITestCase(VppTestCase):
    """Bidirectional Forwarding Detection (BFD) - API"""

    pg0 = None
    pg1 = None

    @classmethod
    def setUpClass(cls):
        super(BFDAPITestCase, cls).setUpClass()

        try:
            cls.create_pg_interfaces(range(2))
            for i in cls.pg_interfaces:
                i.config_ip4()
                i.config_ip6()
                i.resolve_arp()

        except Exception:
            super(BFDAPITestCase, cls).tearDownClass()
            raise

    def setUp(self):
        super(BFDAPITestCase, self).setUp()
        self.factory = AuthKeyFactory()

    def test_add_bfd(self):
        """ create a BFD session """
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4)
        session.add_vpp_config()
        self.logger.debug("Session state is %s", session.state)
        session.remove_vpp_config()
        session.add_vpp_config()
        self.logger.debug("Session state is %s", session.state)
        session.remove_vpp_config()

    def test_double_add(self):
        """ create the same BFD session twice (negative case) """
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4)
        session.add_vpp_config()

        with self.vapi.expect_negative_api_retval():
            session.add_vpp_config()

        session.remove_vpp_config()

    def test_add_bfd6(self):
        """ create IPv6 BFD session """
        session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip6, af=AF_INET6)
        session.add_vpp_config()
        self.logger.debug("Session state is %s", session.state)
        session.remove_vpp_config()
        session.add_vpp_config()
        self.logger.debug("Session state is %s", session.state)
        session.remove_vpp_config()

    def test_mod_bfd(self):
        """ modify BFD session parameters """
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4,
                                   desired_min_tx=50000,
                                   required_min_rx=10000,
                                   detect_mult=1)
        session.add_vpp_config()
        s = session.get_bfd_udp_session_dump_entry()
        self.assert_equal(session.desired_min_tx,
                          s.desired_min_tx,
                          "desired min transmit interval")
        self.assert_equal(session.required_min_rx,
                          s.required_min_rx,
                          "required min receive interval")
        self.assert_equal(session.detect_mult, s.detect_mult, "detect mult")
        session.modify_parameters(desired_min_tx=session.desired_min_tx * 2,
                                  required_min_rx=session.required_min_rx * 2,
                                  detect_mult=session.detect_mult * 2)
        s = session.get_bfd_udp_session_dump_entry()
        self.assert_equal(session.desired_min_tx,
                          s.desired_min_tx,
                          "desired min transmit interval")
        self.assert_equal(session.required_min_rx,
                          s.required_min_rx,
                          "required min receive interval")
        self.assert_equal(session.detect_mult, s.detect_mult, "detect mult")

    def test_add_sha1_keys(self):
        """ add SHA1 keys """
        key_count = 10
        keys = [self.factory.create_random_key(
            self) for i in range(0, key_count)]
        for key in keys:
            self.assertFalse(key.query_vpp_config())
        for key in keys:
            key.add_vpp_config()
        for key in keys:
            self.assertTrue(key.query_vpp_config())
        # remove randomly
        indexes = range(key_count)
        shuffle(indexes)
        removed = []
        for i in indexes:
            key = keys[i]
            key.remove_vpp_config()
            removed.append(i)
            for j in range(key_count):
                key = keys[j]
                if j in removed:
                    self.assertFalse(key.query_vpp_config())
                else:
                    self.assertTrue(key.query_vpp_config())
        # should be removed now
        for key in keys:
            self.assertFalse(key.query_vpp_config())
        # add back and remove again
        for key in keys:
            key.add_vpp_config()
        for key in keys:
            self.assertTrue(key.query_vpp_config())
        for key in keys:
            key.remove_vpp_config()
        for key in keys:
            self.assertFalse(key.query_vpp_config())

    def test_add_bfd_sha1(self):
        """ create a BFD session (SHA1) """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4,
                                   sha1_key=key)
        session.add_vpp_config()
        self.logger.debug("Session state is %s", session.state)
        session.remove_vpp_config()
        session.add_vpp_config()
        self.logger.debug("Session state is %s", session.state)
        session.remove_vpp_config()

    def test_double_add_sha1(self):
        """ create the same BFD session twice (negative case) (SHA1) """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4,
                                   sha1_key=key)
        session.add_vpp_config()
        with self.assertRaises(Exception):
            session.add_vpp_config()

    def test_add_auth_nonexistent_key(self):
        """ create BFD session using non-existent SHA1 (negative case) """
        session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4,
            sha1_key=self.factory.create_random_key(self))
        with self.assertRaises(Exception):
            session.add_vpp_config()

    def test_shared_sha1_key(self):
        """ share single SHA1 key between multiple BFD sessions """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        sessions = [
            VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4,
                             sha1_key=key),
            VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip6,
                             sha1_key=key, af=AF_INET6),
            VppBFDUDPSession(self, self.pg1, self.pg1.remote_ip4,
                             sha1_key=key),
            VppBFDUDPSession(self, self.pg1, self.pg1.remote_ip6,
                             sha1_key=key, af=AF_INET6)]
        for s in sessions:
            s.add_vpp_config()
        removed = 0
        for s in sessions:
            e = key.get_bfd_auth_keys_dump_entry()
            self.assert_equal(e.use_count, len(sessions) - removed,
                              "Use count for shared key")
            s.remove_vpp_config()
            removed += 1
        e = key.get_bfd_auth_keys_dump_entry()
        self.assert_equal(e.use_count, len(sessions) - removed,
                          "Use count for shared key")

    def test_activate_auth(self):
        """ activate SHA1 authentication """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4)
        session.add_vpp_config()
        session.activate_auth(key)

    def test_deactivate_auth(self):
        """ deactivate SHA1 authentication """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4)
        session.add_vpp_config()
        session.activate_auth(key)
        session.deactivate_auth()

    def test_change_key(self):
        """ change SHA1 key """
        key1 = self.factory.create_random_key(self)
        key2 = self.factory.create_random_key(self)
        while key2.conf_key_id == key1.conf_key_id:
            key2 = self.factory.create_random_key(self)
        key1.add_vpp_config()
        key2.add_vpp_config()
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4,
                                   sha1_key=key1)
        session.add_vpp_config()
        session.activate_auth(key2)


class BFDTestSession(object):
    """ BFD session as seen from test framework side """

    def __init__(self, test, interface, af, detect_mult=3, sha1_key=None,
                 bfd_key_id=None, our_seq_number=None):
        self.test = test
        self.af = af
        self.sha1_key = sha1_key
        self.bfd_key_id = bfd_key_id
        self.interface = interface
        self.udp_sport = randint(49152, 65535)
        if our_seq_number is None:
            self.our_seq_number = randint(0, 40000000)
        else:
            self.our_seq_number = our_seq_number
        self.vpp_seq_number = None
        self.my_discriminator = 0
        self.desired_min_tx = 300000
        self.required_min_rx = 300000
        self.required_min_echo_rx = None
        self.detect_mult = detect_mult
        self.diag = BFDDiagCode.no_diagnostic
        self.your_discriminator = None
        self.state = BFDState.down
        self.auth_type = BFDAuthType.no_auth

    def inc_seq_num(self):
        """ increment sequence number, wrapping if needed """
        if self.our_seq_number == 0xFFFFFFFF:
            self.our_seq_number = 0
        else:
            self.our_seq_number += 1

    def update(self, my_discriminator=None, your_discriminator=None,
               desired_min_tx=None, required_min_rx=None,
               required_min_echo_rx=None, detect_mult=None,
               diag=None, state=None, auth_type=None):
        """ update BFD parameters associated with session """
        if my_discriminator is not None:
            self.my_discriminator = my_discriminator
        if your_discriminator is not None:
            self.your_discriminator = your_discriminator
        if required_min_rx is not None:
            self.required_min_rx = required_min_rx
        if required_min_echo_rx is not None:
            self.required_min_echo_rx = required_min_echo_rx
        if desired_min_tx is not None:
            self.desired_min_tx = desired_min_tx
        if detect_mult is not None:
            self.detect_mult = detect_mult
        if diag is not None:
            self.diag = diag
        if state is not None:
            self.state = state
        if auth_type is not None:
            self.auth_type = auth_type

    def fill_packet_fields(self, packet):
        """ set packet fields with known values in packet """
        bfd = packet[BFD]
        if self.my_discriminator:
            self.test.logger.debug("BFD: setting packet.my_discriminator=%s",
                                   self.my_discriminator)
            bfd.my_discriminator = self.my_discriminator
        if self.your_discriminator:
            self.test.logger.debug("BFD: setting packet.your_discriminator=%s",
                                   self.your_discriminator)
            bfd.your_discriminator = self.your_discriminator
        if self.required_min_rx:
            self.test.logger.debug(
                "BFD: setting packet.required_min_rx_interval=%s",
                self.required_min_rx)
            bfd.required_min_rx_interval = self.required_min_rx
        if self.required_min_echo_rx:
            self.test.logger.debug(
                "BFD: setting packet.required_min_echo_rx=%s",
                self.required_min_echo_rx)
            bfd.required_min_echo_rx_interval = self.required_min_echo_rx
        if self.desired_min_tx:
            self.test.logger.debug(
                "BFD: setting packet.desired_min_tx_interval=%s",
                self.desired_min_tx)
            bfd.desired_min_tx_interval = self.desired_min_tx
        if self.detect_mult:
            self.test.logger.debug(
                "BFD: setting packet.detect_mult=%s", self.detect_mult)
            bfd.detect_mult = self.detect_mult
        if self.diag:
            self.test.logger.debug("BFD: setting packet.diag=%s", self.diag)
            bfd.diag = self.diag
        if self.state:
            self.test.logger.debug("BFD: setting packet.state=%s", self.state)
            bfd.state = self.state
        if self.auth_type:
            # this is used by a negative test-case
            self.test.logger.debug("BFD: setting packet.auth_type=%s",
                                   self.auth_type)
            bfd.auth_type = self.auth_type

    def create_packet(self):
        """ create a BFD packet, reflecting the current state of session """
        if self.sha1_key:
            bfd = BFD(flags="A")
            bfd.auth_type = self.sha1_key.auth_type
            bfd.auth_len = BFD.sha1_auth_len
            bfd.auth_key_id = self.bfd_key_id
            bfd.auth_seq_num = self.our_seq_number
            bfd.length = BFD.sha1_auth_len + BFD.bfd_pkt_len
        else:
            bfd = BFD()
        if self.af == AF_INET6:
            packet = (Ether(src=self.interface.remote_mac,
                            dst=self.interface.local_mac) /
                      IPv6(src=self.interface.remote_ip6,
                           dst=self.interface.local_ip6,
                           hlim=255) /
                      UDP(sport=self.udp_sport, dport=BFD.udp_dport) /
                      bfd)
        else:
            packet = (Ether(src=self.interface.remote_mac,
                            dst=self.interface.local_mac) /
                      IP(src=self.interface.remote_ip4,
                         dst=self.interface.local_ip4,
                         ttl=255) /
                      UDP(sport=self.udp_sport, dport=BFD.udp_dport) /
                      bfd)
        self.test.logger.debug("BFD: Creating packet")
        self.fill_packet_fields(packet)
        if self.sha1_key:
            hash_material = str(packet[BFD])[:32] + self.sha1_key.key + \
                "\0" * (20 - len(self.sha1_key.key))
            self.test.logger.debug("BFD: Calculated SHA1 hash: %s" %
                                   hashlib.sha1(hash_material).hexdigest())
            packet[BFD].auth_key_hash = hashlib.sha1(hash_material).digest()
        return packet

    def send_packet(self, packet=None, interface=None):
        """ send packet on interface, creating the packet if needed """
        if packet is None:
            packet = self.create_packet()
        if interface is None:
            interface = self.test.pg0
        self.test.logger.debug(ppp("Sending packet:", packet))
        interface.add_stream(packet)
        self.test.pg_start()

    def verify_sha1_auth(self, packet):
        """ Verify correctness of authentication in BFD layer. """
        bfd = packet[BFD]
        self.test.assert_equal(bfd.auth_len, 28, "Auth section length")
        self.test.assert_equal(bfd.auth_type, self.sha1_key.auth_type,
                               BFDAuthType)
        self.test.assert_equal(bfd.auth_key_id, self.bfd_key_id, "Key ID")
        self.test.assert_equal(bfd.auth_reserved, 0, "Reserved")
        if self.vpp_seq_number is None:
            self.vpp_seq_number = bfd.auth_seq_num
            self.test.logger.debug("Received initial sequence number: %s" %
                                   self.vpp_seq_number)
        else:
            recvd_seq_num = bfd.auth_seq_num
            self.test.logger.debug("Received followup sequence number: %s" %
                                   recvd_seq_num)
            if self.vpp_seq_number < 0xffffffff:
                if self.sha1_key.auth_type == \
                        BFDAuthType.meticulous_keyed_sha1:
                    self.test.assert_equal(recvd_seq_num,
                                           self.vpp_seq_number + 1,
                                           "BFD sequence number")
                else:
                    self.test.assert_in_range(recvd_seq_num,
                                              self.vpp_seq_number,
                                              self.vpp_seq_number + 1,
                                              "BFD sequence number")
            else:
                if self.sha1_key.auth_type == \
                        BFDAuthType.meticulous_keyed_sha1:
                    self.test.assert_equal(recvd_seq_num, 0,
                                           "BFD sequence number")
                else:
                    self.test.assertIn(recvd_seq_num, (self.vpp_seq_number, 0),
                                       "BFD sequence number not one of "
                                       "(%s, 0)" % self.vpp_seq_number)
            self.vpp_seq_number = recvd_seq_num
        # last 20 bytes represent the hash - so replace them with the key,
        # pad the result with zeros and hash the result
        hash_material = bfd.original[:-20] + self.sha1_key.key + \
            "\0" * (20 - len(self.sha1_key.key))
        expected_hash = hashlib.sha1(hash_material).hexdigest()
        self.test.assert_equal(binascii.hexlify(bfd.auth_key_hash),
                               expected_hash, "Auth key hash")

    def verify_bfd(self, packet):
        """ Verify correctness of BFD layer. """
        bfd = packet[BFD]
        self.test.assert_equal(bfd.version, 1, "BFD version")
        self.test.assert_equal(bfd.your_discriminator,
                               self.my_discriminator,
                               "BFD - your discriminator")
        if self.sha1_key:
            self.verify_sha1_auth(packet)


def bfd_session_up(test):
    """ Bring BFD session up """
    test.logger.info("BFD: Waiting for slow hello")
    p = wait_for_bfd_packet(test, 2)
    old_offset = None
    if hasattr(test, 'vpp_clock_offset'):
        old_offset = test.vpp_clock_offset
    test.vpp_clock_offset = time.time() - p.time
    test.logger.debug("BFD: Calculated vpp clock offset: %s",
                      test.vpp_clock_offset)
    if old_offset:
        test.assertAlmostEqual(
            old_offset, test.vpp_clock_offset, delta=0.5,
            msg="vpp clock offset not stable (new: %s, old: %s)" %
            (test.vpp_clock_offset, old_offset))
    test.logger.info("BFD: Sending Init")
    test.test_session.update(my_discriminator=randint(0, 40000000),
                             your_discriminator=p[BFD].my_discriminator,
                             state=BFDState.init)
    if test.test_session.sha1_key and test.test_session.sha1_key.auth_type == \
            BFDAuthType.meticulous_keyed_sha1:
        test.test_session.inc_seq_num()
    test.test_session.send_packet()
    test.logger.info("BFD: Waiting for event")
    e = test.vapi.wait_for_event(1, "bfd_udp_session_details")
    verify_event(test, e, expected_state=BFDState.up)
    test.logger.info("BFD: Session is Up")
    test.test_session.update(state=BFDState.up)
    if test.test_session.sha1_key and test.test_session.sha1_key.auth_type == \
            BFDAuthType.meticulous_keyed_sha1:
        test.test_session.inc_seq_num()
    test.test_session.send_packet()
    test.assert_equal(test.vpp_session.state, BFDState.up, BFDState)


def bfd_session_down(test):
    """ Bring BFD session down """
    test.assert_equal(test.vpp_session.state, BFDState.up, BFDState)
    test.test_session.update(state=BFDState.down)
    if test.test_session.sha1_key and test.test_session.sha1_key.auth_type == \
            BFDAuthType.meticulous_keyed_sha1:
        test.test_session.inc_seq_num()
    test.test_session.send_packet()
    test.logger.info("BFD: Waiting for event")
    e = test.vapi.wait_for_event(1, "bfd_udp_session_details")
    verify_event(test, e, expected_state=BFDState.down)
    test.logger.info("BFD: Session is Down")
    test.assert_equal(test.vpp_session.state, BFDState.down, BFDState)


def verify_bfd_session_config(test, session, state=None):
    dump = session.get_bfd_udp_session_dump_entry()
    test.assertIsNotNone(dump)
    # since dump is not none, we have verified that sw_if_index and addresses
    # are valid (in get_bfd_udp_session_dump_entry)
    if state:
        test.assert_equal(dump.state, state, "session state")
    test.assert_equal(dump.required_min_rx, session.required_min_rx,
                      "required min rx interval")
    test.assert_equal(dump.desired_min_tx, session.desired_min_tx,
                      "desired min tx interval")
    test.assert_equal(dump.detect_mult, session.detect_mult,
                      "detect multiplier")
    if session.sha1_key is None:
        test.assert_equal(dump.is_authenticated, 0, "is_authenticated flag")
    else:
        test.assert_equal(dump.is_authenticated, 1, "is_authenticated flag")
        test.assert_equal(dump.bfd_key_id, session.bfd_key_id,
                          "bfd key id")
        test.assert_equal(dump.conf_key_id,
                          session.sha1_key.conf_key_id,
                          "config key id")


def verify_ip(test, packet):
    """ Verify correctness of IP layer. """
    if test.vpp_session.af == AF_INET6:
        ip = packet[IPv6]
        local_ip = test.pg0.local_ip6
        remote_ip = test.pg0.remote_ip6
        test.assert_equal(ip.hlim, 255, "IPv6 hop limit")
    else:
        ip = packet[IP]
        local_ip = test.pg0.local_ip4
        remote_ip = test.pg0.remote_ip4
        test.assert_equal(ip.ttl, 255, "IPv4 TTL")
    test.assert_equal(ip.src, local_ip, "IP source address")
    test.assert_equal(ip.dst, remote_ip, "IP destination address")


def verify_udp(test, packet):
    """ Verify correctness of UDP layer. """
    udp = packet[UDP]
    test.assert_equal(udp.dport, BFD.udp_dport, "UDP destination port")
    test.assert_in_range(udp.sport, BFD.udp_sport_min, BFD.udp_sport_max,
                         "UDP source port")


def verify_event(test, event, expected_state):
    """ Verify correctness of event values. """
    e = event
    test.logger.debug("BFD: Event: %s" % repr(e))
    test.assert_equal(e.sw_if_index,
                      test.vpp_session.interface.sw_if_index,
                      "BFD interface index")
    is_ipv6 = 0
    if test.vpp_session.af == AF_INET6:
        is_ipv6 = 1
    test.assert_equal(e.is_ipv6, is_ipv6, "is_ipv6")
    if test.vpp_session.af == AF_INET:
        test.assert_equal(e.local_addr[:4], test.vpp_session.local_addr_n,
                          "Local IPv4 address")
        test.assert_equal(e.peer_addr[:4], test.vpp_session.peer_addr_n,
                          "Peer IPv4 address")
    else:
        test.assert_equal(e.local_addr, test.vpp_session.local_addr_n,
                          "Local IPv6 address")
        test.assert_equal(e.peer_addr, test.vpp_session.peer_addr_n,
                          "Peer IPv6 address")
    test.assert_equal(e.state, expected_state, BFDState)


def wait_for_bfd_packet(test, timeout=1, pcap_time_min=None):
    """ wait for BFD packet and verify its correctness

    :param timeout: how long to wait
    :param pcap_time_min: ignore packets with pcap timestamp lower than this

    :returns: tuple (packet, time spent waiting for packet)
    """
    test.logger.info("BFD: Waiting for BFD packet")
    deadline = time.time() + timeout
    counter = 0
    while True:
        counter += 1
        # sanity check
        test.assert_in_range(counter, 0, 100, "number of packets ignored")
        time_left = deadline - time.time()
        if time_left < 0:
            raise CaptureTimeoutError("Packet did not arrive within timeout")
        p = test.pg0.wait_for_packet(timeout=time_left)
        test.logger.debug(ppp("BFD: Got packet:", p))
        if pcap_time_min is not None and p.time < pcap_time_min:
            test.logger.debug(ppp("BFD: ignoring packet (pcap time %s < "
                                  "pcap time min %s):" %
                                  (p.time, pcap_time_min), p))
        else:
            break
    bfd = p[BFD]
    if bfd is None:
        raise Exception(ppp("Unexpected or invalid BFD packet:", p))
    if bfd.payload:
        raise Exception(ppp("Unexpected payload in BFD packet:", bfd))
    verify_ip(test, p)
    verify_udp(test, p)
    test.test_session.verify_bfd(p)
    return p


class BFD4TestCase(VppTestCase):
    """Bidirectional Forwarding Detection (BFD)"""

    pg0 = None
    vpp_clock_offset = None
    vpp_session = None
    test_session = None

    @classmethod
    def setUpClass(cls):
        super(BFD4TestCase, cls).setUpClass()
        try:
            cls.create_pg_interfaces([0])
            cls.create_loopback_interfaces([0])
            cls.loopback0 = cls.lo_interfaces[0]
            cls.loopback0.config_ip4()
            cls.loopback0.admin_up()
            cls.pg0.config_ip4()
            cls.pg0.configure_ipv4_neighbors()
            cls.pg0.admin_up()
            cls.pg0.resolve_arp()

        except Exception:
            super(BFD4TestCase, cls).tearDownClass()
            raise

    def setUp(self):
        super(BFD4TestCase, self).setUp()
        self.factory = AuthKeyFactory()
        self.vapi.want_bfd_events()
        self.pg0.enable_capture()
        try:
            self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                                self.pg0.remote_ip4)
            self.vpp_session.add_vpp_config()
            self.vpp_session.admin_up()
            self.test_session = BFDTestSession(self, self.pg0, AF_INET)
        except:
            self.vapi.want_bfd_events(enable_disable=0)
            raise

    def tearDown(self):
        if not self.vpp_dead:
            self.vapi.want_bfd_events(enable_disable=0)
        self.vapi.collect_events()  # clear the event queue
        super(BFD4TestCase, self).tearDown()

    def test_session_up(self):
        """ bring BFD session up """
        bfd_session_up(self)

    def test_session_up_by_ip(self):
        """ bring BFD session up - first frame looked up by address pair """
        self.logger.info("BFD: Sending Slow control frame")
        self.test_session.update(my_discriminator=randint(0, 40000000))
        self.test_session.send_packet()
        self.pg0.enable_capture()
        p = self.pg0.wait_for_packet(1)
        self.assert_equal(p[BFD].your_discriminator,
                          self.test_session.my_discriminator,
                          "BFD - your discriminator")
        self.assert_equal(p[BFD].state, BFDState.init, BFDState)
        self.test_session.update(your_discriminator=p[BFD].my_discriminator,
                                 state=BFDState.up)
        self.logger.info("BFD: Waiting for event")
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.init)
        self.logger.info("BFD: Sending Up")
        self.test_session.send_packet()
        self.logger.info("BFD: Waiting for event")
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.up)
        self.logger.info("BFD: Session is Up")
        self.test_session.update(state=BFDState.up)
        self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)

    def test_session_down(self):
        """ bring BFD session down """
        bfd_session_up(self)
        bfd_session_down(self)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_hold_up(self):
        """ hold BFD session up """
        bfd_session_up(self)
        for dummy in range(self.test_session.detect_mult * 2):
            wait_for_bfd_packet(self)
            self.test_session.send_packet()
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_slow_timer(self):
        """ verify slow periodic control frames while session down """
        packet_count = 3
        self.logger.info("BFD: Waiting for %d BFD packets", packet_count)
        prev_packet = wait_for_bfd_packet(self, 2)
        for dummy in range(packet_count):
            next_packet = wait_for_bfd_packet(self, 2)
            time_diff = next_packet.time - prev_packet.time
            # spec says the range should be <0.75, 1>, allow extra 0.05 margin
            # to work around timing issues
            self.assert_in_range(
                time_diff, 0.70, 1.05, "time between slow packets")
            prev_packet = next_packet

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_zero_remote_min_rx(self):
        """ no packets when zero remote required min rx interval """
        bfd_session_up(self)
        self.test_session.update(required_min_rx=0)
        self.test_session.send_packet()
        for dummy in range(self.test_session.detect_mult):
            self.sleep(self.vpp_session.required_min_rx / USEC_IN_SEC,
                       "sleep before transmitting bfd packet")
            self.test_session.send_packet()
            try:
                p = wait_for_bfd_packet(self, timeout=0)
                self.logger.error(ppp("Received unexpected packet:", p))
            except CaptureTimeoutError:
                pass
        self.assert_equal(
            len(self.vapi.collect_events()), 0, "number of bfd events")
        self.test_session.update(required_min_rx=300000)
        for dummy in range(3):
            self.test_session.send_packet()
            wait_for_bfd_packet(
                self, timeout=self.test_session.required_min_rx / USEC_IN_SEC)
        self.assert_equal(
            len(self.vapi.collect_events()), 0, "number of bfd events")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_conn_down(self):
        """ verify session goes down after inactivity """
        bfd_session_up(self)
        detection_time = self.test_session.detect_mult *\
            self.vpp_session.required_min_rx / USEC_IN_SEC
        self.sleep(detection_time, "waiting for BFD session time-out")
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.down)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_large_required_min_rx(self):
        """ large remote required min rx interval """
        bfd_session_up(self)
        p = wait_for_bfd_packet(self)
        interval = 3000000
        self.test_session.update(required_min_rx=interval)
        self.test_session.send_packet()
        time_mark = time.time()
        count = 0
        # busy wait here, trying to collect a packet or event, vpp is not
        # allowed to send packets and the session will timeout first - so the
        # Up->Down event must arrive before any packets do
        while time.time() < time_mark + interval / USEC_IN_SEC:
            try:
                p = wait_for_bfd_packet(self, timeout=0)
                # if vpp managed to send a packet before we did the session
                # session update, then that's fine, ignore it
                if p.time < time_mark - self.vpp_clock_offset:
                    continue
                self.logger.error(ppp("Received unexpected packet:", p))
                count += 1
            except CaptureTimeoutError:
                pass
            events = self.vapi.collect_events()
            if len(events) > 0:
                verify_event(self, events[0], BFDState.down)
                break
        self.assert_equal(count, 0, "number of packets received")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_immediate_remote_min_rx_reduction(self):
        """ immediately honor remote required min rx reduction """
        self.vpp_session.remove_vpp_config()
        self.vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4, desired_min_tx=10000)
        self.pg0.enable_capture()
        self.vpp_session.add_vpp_config()
        self.test_session.update(desired_min_tx=1000000,
                                 required_min_rx=1000000)
        bfd_session_up(self)
        reference_packet = wait_for_bfd_packet(self)
        time_mark = time.time()
        interval = 300000
        self.test_session.update(required_min_rx=interval)
        self.test_session.send_packet()
        extra_time = time.time() - time_mark
        p = wait_for_bfd_packet(self)
        # first packet is allowed to be late by time we spent doing the update
        # calculated in extra_time
        self.assert_in_range(p.time - reference_packet.time,
                             .95 * 0.75 * interval / USEC_IN_SEC,
                             1.05 * interval / USEC_IN_SEC + extra_time,
                             "time between BFD packets")
        reference_packet = p
        for dummy in range(3):
            p = wait_for_bfd_packet(self)
            diff = p.time - reference_packet.time
            self.assert_in_range(diff, .95 * .75 * interval / USEC_IN_SEC,
                                 1.05 * interval / USEC_IN_SEC,
                                 "time between BFD packets")
            reference_packet = p

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_modify_req_min_rx_double(self):
        """ modify session - double required min rx """
        bfd_session_up(self)
        p = wait_for_bfd_packet(self)
        self.test_session.update(desired_min_tx=10000,
                                 required_min_rx=10000)
        self.test_session.send_packet()
        # double required min rx
        self.vpp_session.modify_parameters(
            required_min_rx=2 * self.vpp_session.required_min_rx)
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        # poll bit needs to be set
        self.assertIn("P", p.sprintf("%BFD.flags%"),
                      "Poll bit not set in BFD packet")
        # finish poll sequence with final packet
        final = self.test_session.create_packet()
        final[BFD].flags = "F"
        timeout = self.test_session.detect_mult * \
            max(self.test_session.desired_min_tx,
                self.vpp_session.required_min_rx) / USEC_IN_SEC
        self.test_session.send_packet(final)
        time_mark = time.time()
        e = self.vapi.wait_for_event(2 * timeout, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.down)
        time_to_event = time.time() - time_mark
        self.assert_in_range(time_to_event, .9 * timeout,
                             1.1 * timeout, "session timeout")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_modify_req_min_rx_halve(self):
        """ modify session - halve required min rx """
        self.vpp_session.modify_parameters(
            required_min_rx=2 * self.vpp_session.required_min_rx)
        bfd_session_up(self)
        p = wait_for_bfd_packet(self)
        self.test_session.update(desired_min_tx=10000,
                                 required_min_rx=10000)
        self.test_session.send_packet()
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        # halve required min rx
        old_required_min_rx = self.vpp_session.required_min_rx
        self.vpp_session.modify_parameters(
            required_min_rx=0.5 * self.vpp_session.required_min_rx)
        # now we wait 0.8*3*old-req-min-rx and the session should still be up
        self.sleep(0.8 * self.vpp_session.detect_mult *
                   old_required_min_rx / USEC_IN_SEC,
                   "wait before finishing poll sequence")
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")
        p = wait_for_bfd_packet(self)
        # poll bit needs to be set
        self.assertIn("P", p.sprintf("%BFD.flags%"),
                      "Poll bit not set in BFD packet")
        # finish poll sequence with final packet
        final = self.test_session.create_packet()
        final[BFD].flags = "F"
        self.test_session.send_packet(final)
        # now the session should time out under new conditions
        detection_time = self.test_session.detect_mult *\
            self.vpp_session.required_min_rx / USEC_IN_SEC
        before = time.time()
        e = self.vapi.wait_for_event(
            2 * detection_time, "bfd_udp_session_details")
        after = time.time()
        self.assert_in_range(after - before,
                             0.9 * detection_time,
                             1.1 * detection_time,
                             "time before bfd session goes down")
        verify_event(self, e, expected_state=BFDState.down)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_modify_detect_mult(self):
        """ modify detect multiplier """
        bfd_session_up(self)
        p = wait_for_bfd_packet(self)
        self.vpp_session.modify_parameters(detect_mult=1)
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        self.assert_equal(self.vpp_session.detect_mult,
                          p[BFD].detect_mult,
                          "detect mult")
        # poll bit must not be set
        self.assertNotIn("P", p.sprintf("%BFD.flags%"),
                         "Poll bit not set in BFD packet")
        self.vpp_session.modify_parameters(detect_mult=10)
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        self.assert_equal(self.vpp_session.detect_mult,
                          p[BFD].detect_mult,
                          "detect mult")
        # poll bit must not be set
        self.assertNotIn("P", p.sprintf("%BFD.flags%"),
                         "Poll bit not set in BFD packet")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_queued_poll(self):
        """ test poll sequence queueing """
        bfd_session_up(self)
        p = wait_for_bfd_packet(self)
        self.vpp_session.modify_parameters(
            required_min_rx=2 * self.vpp_session.required_min_rx)
        p = wait_for_bfd_packet(self)
        poll_sequence_start = time.time()
        poll_sequence_length_min = 0.5
        send_final_after = time.time() + poll_sequence_length_min
        # poll bit needs to be set
        self.assertIn("P", p.sprintf("%BFD.flags%"),
                      "Poll bit not set in BFD packet")
        self.assert_equal(p[BFD].required_min_rx_interval,
                          self.vpp_session.required_min_rx,
                          "BFD required min rx interval")
        self.vpp_session.modify_parameters(
            required_min_rx=2 * self.vpp_session.required_min_rx)
        # 2nd poll sequence should be queued now
        # don't send the reply back yet, wait for some time to emulate
        # longer round-trip time
        packet_count = 0
        while time.time() < send_final_after:
            self.test_session.send_packet()
            p = wait_for_bfd_packet(self)
            self.assert_equal(len(self.vapi.collect_events()), 0,
                              "number of bfd events")
            self.assert_equal(p[BFD].required_min_rx_interval,
                              self.vpp_session.required_min_rx,
                              "BFD required min rx interval")
            packet_count += 1
            # poll bit must be set
            self.assertIn("P", p.sprintf("%BFD.flags%"),
                          "Poll bit not set in BFD packet")
        final = self.test_session.create_packet()
        final[BFD].flags = "F"
        self.test_session.send_packet(final)
        # finish 1st with final
        poll_sequence_length = time.time() - poll_sequence_start
        # vpp must wait for some time before starting new poll sequence
        poll_no_2_started = False
        for dummy in range(2 * packet_count):
            p = wait_for_bfd_packet(self)
            self.assert_equal(len(self.vapi.collect_events()), 0,
                              "number of bfd events")
            if "P" in p.sprintf("%BFD.flags%"):
                poll_no_2_started = True
                if time.time() < poll_sequence_start + poll_sequence_length:
                    raise Exception("VPP started 2nd poll sequence too soon")
                final = self.test_session.create_packet()
                final[BFD].flags = "F"
                self.test_session.send_packet(final)
                break
            else:
                self.test_session.send_packet()
        self.assertTrue(poll_no_2_started, "2nd poll sequence not performed")
        # finish 2nd with final
        final = self.test_session.create_packet()
        final[BFD].flags = "F"
        self.test_session.send_packet(final)
        p = wait_for_bfd_packet(self)
        # poll bit must not be set
        self.assertNotIn("P", p.sprintf("%BFD.flags%"),
                         "Poll bit set in BFD packet")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_poll_response(self):
        """ test correct response to control frame with poll bit set """
        bfd_session_up(self)
        poll = self.test_session.create_packet()
        poll[BFD].flags = "P"
        self.test_session.send_packet(poll)
        final = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        self.assertIn("F", final.sprintf("%BFD.flags%"))

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_no_periodic_if_remote_demand(self):
        """ no periodic frames outside poll sequence if remote demand set """
        bfd_session_up(self)
        demand = self.test_session.create_packet()
        demand[BFD].flags = "D"
        self.test_session.send_packet(demand)
        transmit_time = 0.9 \
            * max(self.vpp_session.required_min_rx,
                  self.test_session.desired_min_tx) \
            / USEC_IN_SEC
        count = 0
        for dummy in range(self.test_session.detect_mult * 2):
            time.sleep(transmit_time)
            self.test_session.send_packet(demand)
            try:
                p = wait_for_bfd_packet(self, timeout=0)
                self.logger.error(ppp("Received unexpected packet:", p))
                count += 1
            except CaptureTimeoutError:
                pass
        events = self.vapi.collect_events()
        for e in events:
            self.logger.error("Received unexpected event: %s", e)
        self.assert_equal(count, 0, "number of packets received")
        self.assert_equal(len(events), 0, "number of events received")

    def test_echo_looped_back(self):
        """ echo packets looped back """
        # don't need a session in this case..
        self.vpp_session.remove_vpp_config()
        self.pg0.enable_capture()
        echo_packet_count = 10
        # random source port low enough to increment a few times..
        udp_sport_tx = randint(1, 50000)
        udp_sport_rx = udp_sport_tx
        echo_packet = (Ether(src=self.pg0.remote_mac,
                             dst=self.pg0.local_mac) /
                       IP(src=self.pg0.remote_ip4,
                          dst=self.pg0.remote_ip4) /
                       UDP(dport=BFD.udp_dport_echo) /
                       Raw("this should be looped back"))
        for dummy in range(echo_packet_count):
            self.sleep(.01, "delay between echo packets")
            echo_packet[UDP].sport = udp_sport_tx
            udp_sport_tx += 1
            self.logger.debug(ppp("Sending packet:", echo_packet))
            self.pg0.add_stream(echo_packet)
            self.pg_start()
        for dummy in range(echo_packet_count):
            p = self.pg0.wait_for_packet(1)
            self.logger.debug(ppp("Got packet:", p))
            ether = p[Ether]
            self.assert_equal(self.pg0.remote_mac,
                              ether.dst, "Destination MAC")
            self.assert_equal(self.pg0.local_mac, ether.src, "Source MAC")
            ip = p[IP]
            self.assert_equal(self.pg0.remote_ip4, ip.dst, "Destination IP")
            self.assert_equal(self.pg0.remote_ip4, ip.src, "Destination IP")
            udp = p[UDP]
            self.assert_equal(udp.dport, BFD.udp_dport_echo,
                              "UDP destination port")
            self.assert_equal(udp.sport, udp_sport_rx, "UDP source port")
            udp_sport_rx += 1
            # need to compare the hex payload here, otherwise BFD_vpp_echo
            # gets in way
            self.assertEqual(str(p[UDP].payload),
                             str(echo_packet[UDP].payload),
                             "Received packet is not the echo packet sent")
        self.assert_equal(udp_sport_tx, udp_sport_rx, "UDP source port (== "
                          "ECHO packet identifier for test purposes)")

    def test_echo(self):
        """ echo function """
        bfd_session_up(self)
        self.test_session.update(required_min_echo_rx=50000)
        self.test_session.send_packet()
        detection_time = self.test_session.detect_mult *\
            self.vpp_session.required_min_rx / USEC_IN_SEC
        # echo shouldn't work without echo source set
        for dummy in range(3):
            sleep = 0.75 * detection_time
            self.sleep(sleep, "delay before sending bfd packet")
            self.test_session.send_packet()
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        self.assert_equal(p[BFD].required_min_rx_interval,
                          self.vpp_session.required_min_rx,
                          "BFD required min rx interval")
        self.vapi.bfd_udp_set_echo_source(self.loopback0.sw_if_index)
        # should be turned on - loopback echo packets
        for dummy in range(3):
            loop_until = time.time() + 0.75 * detection_time
            while time.time() < loop_until:
                p = self.pg0.wait_for_packet(1)
                self.logger.debug(ppp("Got packet:", p))
                if p[UDP].dport == BFD.udp_dport_echo:
                    self.assert_equal(
                        p[IP].dst, self.pg0.local_ip4, "BFD ECHO dst IP")
                    self.assertNotEqual(p[IP].src, self.loopback0.local_ip4,
                                        "BFD ECHO src IP equal to loopback IP")
                    self.logger.debug(ppp("Looping back packet:", p))
                    self.assert_equal(p[Ether].dst, self.pg0.remote_mac,
                                      "ECHO packet destination MAC address")
                    p[Ether].dst = self.pg0.local_mac
                    self.pg0.add_stream(p)
                    self.pg_start()
                elif p.haslayer(BFD):
                    self.assertGreaterEqual(p[BFD].required_min_rx_interval,
                                            1000000)
                    if "P" in p.sprintf("%BFD.flags%"):
                        final = self.test_session.create_packet()
                        final[BFD].flags = "F"
                        self.test_session.send_packet(final)
                else:
                    raise Exception(ppp("Received unknown packet:", p))

                self.assert_equal(len(self.vapi.collect_events()), 0,
                                  "number of bfd events")
            self.test_session.send_packet()

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_echo_fail(self):
        """ session goes down if echo function fails """
        bfd_session_up(self)
        self.test_session.update(required_min_echo_rx=50000)
        self.test_session.send_packet()
        detection_time = self.test_session.detect_mult *\
            self.vpp_session.required_min_rx / USEC_IN_SEC
        self.vapi.bfd_udp_set_echo_source(self.loopback0.sw_if_index)
        # echo function should be used now, but we will drop the echo packets
        verified_diag = False
        for dummy in range(3):
            loop_until = time.time() + 0.75 * detection_time
            while time.time() < loop_until:
                p = self.pg0.wait_for_packet(1)
                self.logger.debug(ppp("Got packet:", p))
                if p[UDP].dport == BFD.udp_dport_echo:
                    # dropped
                    pass
                elif p.haslayer(BFD):
                    if "P" in p.sprintf("%BFD.flags%"):
                        self.assertGreaterEqual(
                            p[BFD].required_min_rx_interval,
                            1000000)
                        final = self.test_session.create_packet()
                        final[BFD].flags = "F"
                        self.test_session.send_packet(final)
                    if p[BFD].state == BFDState.down:
                        self.assert_equal(p[BFD].diag,
                                          BFDDiagCode.echo_function_failed,
                                          BFDDiagCode)
                        verified_diag = True
                else:
                    raise Exception(ppp("Received unknown packet:", p))
            self.test_session.send_packet()
        events = self.vapi.collect_events()
        self.assert_equal(len(events), 1, "number of bfd events")
        self.assert_equal(events[0].state, BFDState.down, BFDState)
        self.assertTrue(verified_diag, "Incorrect diagnostics code received")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_echo_stop(self):
        """ echo function stops if peer sets required min echo rx zero """
        bfd_session_up(self)
        self.test_session.update(required_min_echo_rx=50000)
        self.test_session.send_packet()
        self.vapi.bfd_udp_set_echo_source(self.loopback0.sw_if_index)
        # wait for first echo packet
        while True:
            p = self.pg0.wait_for_packet(1)
            self.logger.debug(ppp("Got packet:", p))
            if p[UDP].dport == BFD.udp_dport_echo:
                self.logger.debug(ppp("Looping back packet:", p))
                p[Ether].dst = self.pg0.local_mac
                self.pg0.add_stream(p)
                self.pg_start()
                break
            elif p.haslayer(BFD):
                # ignore BFD
                pass
            else:
                raise Exception(ppp("Received unknown packet:", p))
        self.test_session.update(required_min_echo_rx=0)
        self.test_session.send_packet()
        # echo packets shouldn't arrive anymore
        for dummy in range(5):
            wait_for_bfd_packet(
                self, pcap_time_min=time.time() - self.vpp_clock_offset)
            self.test_session.send_packet()
            events = self.vapi.collect_events()
            self.assert_equal(len(events), 0, "number of bfd events")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_echo_source_removed(self):
        """ echo function stops if echo source is removed """
        bfd_session_up(self)
        self.test_session.update(required_min_echo_rx=50000)
        self.test_session.send_packet()
        self.vapi.bfd_udp_set_echo_source(self.loopback0.sw_if_index)
        # wait for first echo packet
        while True:
            p = self.pg0.wait_for_packet(1)
            self.logger.debug(ppp("Got packet:", p))
            if p[UDP].dport == BFD.udp_dport_echo:
                self.logger.debug(ppp("Looping back packet:", p))
                p[Ether].dst = self.pg0.local_mac
                self.pg0.add_stream(p)
                self.pg_start()
                break
            elif p.haslayer(BFD):
                # ignore BFD
                pass
            else:
                raise Exception(ppp("Received unknown packet:", p))
        self.vapi.bfd_udp_del_echo_source()
        self.test_session.send_packet()
        # echo packets shouldn't arrive anymore
        for dummy in range(5):
            wait_for_bfd_packet(
                self, pcap_time_min=time.time() - self.vpp_clock_offset)
            self.test_session.send_packet()
            events = self.vapi.collect_events()
            self.assert_equal(len(events), 0, "number of bfd events")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_stale_echo(self):
        """ stale echo packets don't keep a session up """
        bfd_session_up(self)
        self.test_session.update(required_min_echo_rx=50000)
        self.vapi.bfd_udp_set_echo_source(self.loopback0.sw_if_index)
        self.test_session.send_packet()
        # should be turned on - loopback echo packets
        echo_packet = None
        timeout_at = None
        timeout_ok = False
        for dummy in range(10 * self.vpp_session.detect_mult):
            p = self.pg0.wait_for_packet(1)
            if p[UDP].dport == BFD.udp_dport_echo:
                if echo_packet is None:
                    self.logger.debug(ppp("Got first echo packet:", p))
                    echo_packet = p
                    timeout_at = time.time() + self.vpp_session.detect_mult * \
                        self.test_session.required_min_echo_rx / USEC_IN_SEC
                else:
                    self.logger.debug(ppp("Got followup echo packet:", p))
                self.logger.debug(ppp("Looping back first echo packet:", p))
                echo_packet[Ether].dst = self.pg0.local_mac
                self.pg0.add_stream(echo_packet)
                self.pg_start()
            elif p.haslayer(BFD):
                self.logger.debug(ppp("Got packet:", p))
                if "P" in p.sprintf("%BFD.flags%"):
                    final = self.test_session.create_packet()
                    final[BFD].flags = "F"
                    self.test_session.send_packet(final)
                if p[BFD].state == BFDState.down:
                    self.assertIsNotNone(
                        timeout_at,
                        "Session went down before first echo packet received")
                    now = time.time()
                    self.assertGreaterEqual(
                        now, timeout_at,
                        "Session timeout at %s, but is expected at %s" %
                        (now, timeout_at))
                    self.assert_equal(p[BFD].diag,
                                      BFDDiagCode.echo_function_failed,
                                      BFDDiagCode)
                    events = self.vapi.collect_events()
                    self.assert_equal(len(events), 1, "number of bfd events")
                    self.assert_equal(events[0].state, BFDState.down, BFDState)
                    timeout_ok = True
                    break
            else:
                raise Exception(ppp("Received unknown packet:", p))
            self.test_session.send_packet()
        self.assertTrue(timeout_ok, "Expected timeout event didn't occur")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_invalid_echo_checksum(self):
        """ echo packets with invalid checksum don't keep a session up """
        bfd_session_up(self)
        self.test_session.update(required_min_echo_rx=50000)
        self.vapi.bfd_udp_set_echo_source(self.loopback0.sw_if_index)
        self.test_session.send_packet()
        # should be turned on - loopback echo packets
        timeout_at = None
        timeout_ok = False
        for dummy in range(10 * self.vpp_session.detect_mult):
            p = self.pg0.wait_for_packet(1)
            if p[UDP].dport == BFD.udp_dport_echo:
                self.logger.debug(ppp("Got echo packet:", p))
                if timeout_at is None:
                    timeout_at = time.time() + self.vpp_session.detect_mult * \
                        self.test_session.required_min_echo_rx / USEC_IN_SEC
                p[BFD_vpp_echo].checksum = getrandbits(64)
                p[Ether].dst = self.pg0.local_mac
                self.logger.debug(ppp("Looping back modified echo packet:", p))
                self.pg0.add_stream(p)
                self.pg_start()
            elif p.haslayer(BFD):
                self.logger.debug(ppp("Got packet:", p))
                if "P" in p.sprintf("%BFD.flags%"):
                    final = self.test_session.create_packet()
                    final[BFD].flags = "F"
                    self.test_session.send_packet(final)
                if p[BFD].state == BFDState.down:
                    self.assertIsNotNone(
                        timeout_at,
                        "Session went down before first echo packet received")
                    now = time.time()
                    self.assertGreaterEqual(
                        now, timeout_at,
                        "Session timeout at %s, but is expected at %s" %
                        (now, timeout_at))
                    self.assert_equal(p[BFD].diag,
                                      BFDDiagCode.echo_function_failed,
                                      BFDDiagCode)
                    events = self.vapi.collect_events()
                    self.assert_equal(len(events), 1, "number of bfd events")
                    self.assert_equal(events[0].state, BFDState.down, BFDState)
                    timeout_ok = True
                    break
            else:
                raise Exception(ppp("Received unknown packet:", p))
            self.test_session.send_packet()
        self.assertTrue(timeout_ok, "Expected timeout event didn't occur")

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_admin_up_down(self):
        """ put session admin-up and admin-down """
        bfd_session_up(self)
        self.vpp_session.admin_down()
        self.pg0.enable_capture()
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.admin_down)
        for dummy in range(2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.admin_down, BFDState)
        # try to bring session up - shouldn't be possible
        self.test_session.update(state=BFDState.init)
        self.test_session.send_packet()
        for dummy in range(2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.admin_down, BFDState)
        self.vpp_session.admin_up()
        self.test_session.update(state=BFDState.down)
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.down)
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        self.assert_equal(p[BFD].state, BFDState.down, BFDState)
        self.test_session.send_packet()
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        self.assert_equal(p[BFD].state, BFDState.init, BFDState)
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.init)
        self.test_session.update(state=BFDState.up)
        self.test_session.send_packet()
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        self.assert_equal(p[BFD].state, BFDState.up, BFDState)
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.up)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_config_change_remote_demand(self):
        """ configuration change while peer in demand mode """
        bfd_session_up(self)
        demand = self.test_session.create_packet()
        demand[BFD].flags = "D"
        self.test_session.send_packet(demand)
        self.vpp_session.modify_parameters(
            required_min_rx=2 * self.vpp_session.required_min_rx)
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        # poll bit must be set
        self.assertIn("P", p.sprintf("%BFD.flags%"), "Poll bit not set")
        # terminate poll sequence
        final = self.test_session.create_packet()
        final[BFD].flags = "D+F"
        self.test_session.send_packet(final)
        # vpp should be quiet now again
        transmit_time = 0.9 \
            * max(self.vpp_session.required_min_rx,
                  self.test_session.desired_min_tx) \
            / USEC_IN_SEC
        count = 0
        for dummy in range(self.test_session.detect_mult * 2):
            time.sleep(transmit_time)
            self.test_session.send_packet(demand)
            try:
                p = wait_for_bfd_packet(self, timeout=0)
                self.logger.error(ppp("Received unexpected packet:", p))
                count += 1
            except CaptureTimeoutError:
                pass
        events = self.vapi.collect_events()
        for e in events:
            self.logger.error("Received unexpected event: %s", e)
        self.assert_equal(count, 0, "number of packets received")
        self.assert_equal(len(events), 0, "number of events received")


class BFD6TestCase(VppTestCase):
    """Bidirectional Forwarding Detection (BFD) (IPv6) """

    pg0 = None
    vpp_clock_offset = None
    vpp_session = None
    test_session = None

    @classmethod
    def setUpClass(cls):
        super(BFD6TestCase, cls).setUpClass()
        try:
            cls.create_pg_interfaces([0])
            cls.pg0.config_ip6()
            cls.pg0.configure_ipv6_neighbors()
            cls.pg0.admin_up()
            cls.pg0.resolve_ndp()
            cls.create_loopback_interfaces([0])
            cls.loopback0 = cls.lo_interfaces[0]
            cls.loopback0.config_ip6()
            cls.loopback0.admin_up()

        except Exception:
            super(BFD6TestCase, cls).tearDownClass()
            raise

    def setUp(self):
        super(BFD6TestCase, self).setUp()
        self.factory = AuthKeyFactory()
        self.vapi.want_bfd_events()
        self.pg0.enable_capture()
        try:
            self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                                self.pg0.remote_ip6,
                                                af=AF_INET6)
            self.vpp_session.add_vpp_config()
            self.vpp_session.admin_up()
            self.test_session = BFDTestSession(self, self.pg0, AF_INET6)
            self.logger.debug(self.vapi.cli("show adj nbr"))
        except:
            self.vapi.want_bfd_events(enable_disable=0)
            raise

    def tearDown(self):
        if not self.vpp_dead:
            self.vapi.want_bfd_events(enable_disable=0)
        self.vapi.collect_events()  # clear the event queue
        super(BFD6TestCase, self).tearDown()

    def test_session_up(self):
        """ bring BFD session up """
        bfd_session_up(self)

    def test_session_up_by_ip(self):
        """ bring BFD session up - first frame looked up by address pair """
        self.logger.info("BFD: Sending Slow control frame")
        self.test_session.update(my_discriminator=randint(0, 40000000))
        self.test_session.send_packet()
        self.pg0.enable_capture()
        p = self.pg0.wait_for_packet(1)
        self.assert_equal(p[BFD].your_discriminator,
                          self.test_session.my_discriminator,
                          "BFD - your discriminator")
        self.assert_equal(p[BFD].state, BFDState.init, BFDState)
        self.test_session.update(your_discriminator=p[BFD].my_discriminator,
                                 state=BFDState.up)
        self.logger.info("BFD: Waiting for event")
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.init)
        self.logger.info("BFD: Sending Up")
        self.test_session.send_packet()
        self.logger.info("BFD: Waiting for event")
        e = self.vapi.wait_for_event(1, "bfd_udp_session_details")
        verify_event(self, e, expected_state=BFDState.up)
        self.logger.info("BFD: Session is Up")
        self.test_session.update(state=BFDState.up)
        self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_hold_up(self):
        """ hold BFD session up """
        bfd_session_up(self)
        for dummy in range(self.test_session.detect_mult * 2):
            wait_for_bfd_packet(self)
            self.test_session.send_packet()
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)

    def test_echo_looped_back(self):
        """ echo packets looped back """
        # don't need a session in this case..
        self.vpp_session.remove_vpp_config()
        self.pg0.enable_capture()
        echo_packet_count = 10
        # random source port low enough to increment a few times..
        udp_sport_tx = randint(1, 50000)
        udp_sport_rx = udp_sport_tx
        echo_packet = (Ether(src=self.pg0.remote_mac,
                             dst=self.pg0.local_mac) /
                       IPv6(src=self.pg0.remote_ip6,
                            dst=self.pg0.remote_ip6) /
                       UDP(dport=BFD.udp_dport_echo) /
                       Raw("this should be looped back"))
        for dummy in range(echo_packet_count):
            self.sleep(.01, "delay between echo packets")
            echo_packet[UDP].sport = udp_sport_tx
            udp_sport_tx += 1
            self.logger.debug(ppp("Sending packet:", echo_packet))
            self.pg0.add_stream(echo_packet)
            self.pg_start()
        for dummy in range(echo_packet_count):
            p = self.pg0.wait_for_packet(1)
            self.logger.debug(ppp("Got packet:", p))
            ether = p[Ether]
            self.assert_equal(self.pg0.remote_mac,
                              ether.dst, "Destination MAC")
            self.assert_equal(self.pg0.local_mac, ether.src, "Source MAC")
            ip = p[IPv6]
            self.assert_equal(self.pg0.remote_ip6, ip.dst, "Destination IP")
            self.assert_equal(self.pg0.remote_ip6, ip.src, "Destination IP")
            udp = p[UDP]
            self.assert_equal(udp.dport, BFD.udp_dport_echo,
                              "UDP destination port")
            self.assert_equal(udp.sport, udp_sport_rx, "UDP source port")
            udp_sport_rx += 1
            # need to compare the hex payload here, otherwise BFD_vpp_echo
            # gets in way
            self.assertEqual(str(p[UDP].payload),
                             str(echo_packet[UDP].payload),
                             "Received packet is not the echo packet sent")
        self.assert_equal(udp_sport_tx, udp_sport_rx, "UDP source port (== "
                          "ECHO packet identifier for test purposes)")
        self.assert_equal(udp_sport_tx, udp_sport_rx, "UDP source port (== "
                          "ECHO packet identifier for test purposes)")

    def test_echo(self):
        """ echo function used """
        bfd_session_up(self)
        self.test_session.update(required_min_echo_rx=50000)
        self.test_session.send_packet()
        detection_time = self.test_session.detect_mult *\
            self.vpp_session.required_min_rx / USEC_IN_SEC
        # echo shouldn't work without echo source set
        for dummy in range(3):
            sleep = 0.75 * detection_time
            self.sleep(sleep, "delay before sending bfd packet")
            self.test_session.send_packet()
        p = wait_for_bfd_packet(
            self, pcap_time_min=time.time() - self.vpp_clock_offset)
        self.assert_equal(p[BFD].required_min_rx_interval,
                          self.vpp_session.required_min_rx,
                          "BFD required min rx interval")
        self.vapi.bfd_udp_set_echo_source(self.loopback0.sw_if_index)
        # should be turned on - loopback echo packets
        for dummy in range(3):
            loop_until = time.time() + 0.75 * detection_time
            while time.time() < loop_until:
                p = self.pg0.wait_for_packet(1)
                self.logger.debug(ppp("Got packet:", p))
                if p[UDP].dport == BFD.udp_dport_echo:
                    self.assert_equal(
                        p[IPv6].dst, self.pg0.local_ip6, "BFD ECHO dst IP")
                    self.assertNotEqual(p[IPv6].src, self.loopback0.local_ip6,
                                        "BFD ECHO src IP equal to loopback IP")
                    self.logger.debug(ppp("Looping back packet:", p))
                    self.assert_equal(p[Ether].dst, self.pg0.remote_mac,
                                      "ECHO packet destination MAC address")
                    p[Ether].dst = self.pg0.local_mac
                    self.pg0.add_stream(p)
                    self.pg_start()
                elif p.haslayer(BFD):
                    self.assertGreaterEqual(p[BFD].required_min_rx_interval,
                                            1000000)
                    if "P" in p.sprintf("%BFD.flags%"):
                        final = self.test_session.create_packet()
                        final[BFD].flags = "F"
                        self.test_session.send_packet(final)
                else:
                    raise Exception(ppp("Received unknown packet:", p))

                self.assert_equal(len(self.vapi.collect_events()), 0,
                                  "number of bfd events")
            self.test_session.send_packet()


class BFDSHA1TestCase(VppTestCase):
    """Bidirectional Forwarding Detection (BFD) (SHA1 auth) """

    pg0 = None
    vpp_clock_offset = None
    vpp_session = None
    test_session = None

    @classmethod
    def setUpClass(cls):
        super(BFDSHA1TestCase, cls).setUpClass()
        try:
            cls.create_pg_interfaces([0])
            cls.pg0.config_ip4()
            cls.pg0.admin_up()
            cls.pg0.resolve_arp()

        except Exception:
            super(BFDSHA1TestCase, cls).tearDownClass()
            raise

    def setUp(self):
        super(BFDSHA1TestCase, self).setUp()
        self.factory = AuthKeyFactory()
        self.vapi.want_bfd_events()
        self.pg0.enable_capture()

    def tearDown(self):
        if not self.vpp_dead:
            self.vapi.want_bfd_events(enable_disable=0)
        self.vapi.collect_events()  # clear the event queue
        super(BFDSHA1TestCase, self).tearDown()

    def test_session_up(self):
        """ bring BFD session up """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4,
                                            sha1_key=key)
        self.vpp_session.add_vpp_config()
        self.vpp_session.admin_up()
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=self.vpp_session.bfd_key_id)
        bfd_session_up(self)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_hold_up(self):
        """ hold BFD session up """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4,
                                            sha1_key=key)
        self.vpp_session.add_vpp_config()
        self.vpp_session.admin_up()
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=self.vpp_session.bfd_key_id)
        bfd_session_up(self)
        for dummy in range(self.test_session.detect_mult * 2):
            wait_for_bfd_packet(self)
            self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_hold_up_meticulous(self):
        """ hold BFD session up - meticulous auth """
        key = self.factory.create_random_key(
            self, BFDAuthType.meticulous_keyed_sha1)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4, sha1_key=key)
        self.vpp_session.add_vpp_config()
        self.vpp_session.admin_up()
        # specify sequence number so that it wraps
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=self.vpp_session.bfd_key_id,
            our_seq_number=0xFFFFFFFF - 4)
        bfd_session_up(self)
        for dummy in range(30):
            wait_for_bfd_packet(self)
            self.test_session.inc_seq_num()
            self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_send_bad_seq_number(self):
        """ session is not kept alive by msgs with bad sequence numbers"""
        key = self.factory.create_random_key(
            self, BFDAuthType.meticulous_keyed_sha1)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4, sha1_key=key)
        self.vpp_session.add_vpp_config()
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=self.vpp_session.bfd_key_id)
        bfd_session_up(self)
        detection_time = self.test_session.detect_mult *\
            self.vpp_session.required_min_rx / USEC_IN_SEC
        send_until = time.time() + 2 * detection_time
        while time.time() < send_until:
            self.test_session.send_packet()
            self.sleep(0.7 * self.vpp_session.required_min_rx / USEC_IN_SEC,
                       "time between bfd packets")
        e = self.vapi.collect_events()
        # session should be down now, because the sequence numbers weren't
        # updated
        self.assert_equal(len(e), 1, "number of bfd events")
        verify_event(self, e[0], expected_state=BFDState.down)

    def execute_rogue_session_scenario(self, vpp_bfd_udp_session,
                                       legitimate_test_session,
                                       rogue_test_session,
                                       rogue_bfd_values=None):
        """ execute a rogue session interaction scenario

        1. create vpp session, add config
        2. bring the legitimate session up
        3. copy the bfd values from legitimate session to rogue session
        4. apply rogue_bfd_values to rogue session
        5. set rogue session state to down
        6. send message to take the session down from the rogue session
        7. assert that the legitimate session is unaffected
        """

        self.vpp_session = vpp_bfd_udp_session
        self.vpp_session.add_vpp_config()
        self.test_session = legitimate_test_session
        # bring vpp session up
        bfd_session_up(self)
        # send packet from rogue session
        rogue_test_session.update(
            my_discriminator=self.test_session.my_discriminator,
            your_discriminator=self.test_session.your_discriminator,
            desired_min_tx=self.test_session.desired_min_tx,
            required_min_rx=self.test_session.required_min_rx,
            detect_mult=self.test_session.detect_mult,
            diag=self.test_session.diag,
            state=self.test_session.state,
            auth_type=self.test_session.auth_type)
        if rogue_bfd_values:
            rogue_test_session.update(**rogue_bfd_values)
        rogue_test_session.update(state=BFDState.down)
        rogue_test_session.send_packet()
        wait_for_bfd_packet(self)
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_mismatch_auth(self):
        """ session is not brought down by unauthenticated msg """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4, sha1_key=key)
        legitimate_test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=vpp_session.bfd_key_id)
        rogue_test_session = BFDTestSession(self, self.pg0, AF_INET)
        self.execute_rogue_session_scenario(vpp_session,
                                            legitimate_test_session,
                                            rogue_test_session)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_mismatch_bfd_key_id(self):
        """ session is not brought down by msg with non-existent key-id """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4, sha1_key=key)
        # pick a different random bfd key id
        x = randint(0, 255)
        while x == vpp_session.bfd_key_id:
            x = randint(0, 255)
        legitimate_test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=vpp_session.bfd_key_id)
        rogue_test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key, bfd_key_id=x)
        self.execute_rogue_session_scenario(vpp_session,
                                            legitimate_test_session,
                                            rogue_test_session)

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_mismatched_auth_type(self):
        """ session is not brought down by msg with wrong auth type """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4, sha1_key=key)
        legitimate_test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=vpp_session.bfd_key_id)
        rogue_test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=vpp_session.bfd_key_id)
        self.execute_rogue_session_scenario(
            vpp_session, legitimate_test_session, rogue_test_session,
            {'auth_type': BFDAuthType.keyed_md5})

    @unittest.skipUnless(running_extended_tests(), "part of extended tests")
    def test_restart(self):
        """ simulate remote peer restart and resynchronization """
        key = self.factory.create_random_key(
            self, BFDAuthType.meticulous_keyed_sha1)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4, sha1_key=key)
        self.vpp_session.add_vpp_config()
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=self.vpp_session.bfd_key_id, our_seq_number=0)
        bfd_session_up(self)
        # don't send any packets for 2*detection_time
        detection_time = self.test_session.detect_mult *\
            self.vpp_session.required_min_rx / USEC_IN_SEC
        self.sleep(2 * detection_time, "simulating peer restart")
        events = self.vapi.collect_events()
        self.assert_equal(len(events), 1, "number of bfd events")
        verify_event(self, events[0], expected_state=BFDState.down)
        self.test_session.update(state=BFDState.down)
        # reset sequence number
        self.test_session.our_seq_number = 0
        self.test_session.vpp_seq_number = None
        # now throw away any pending packets
        self.pg0.enable_capture()
        bfd_session_up(self)


@unittest.skipUnless(running_extended_tests(), "part of extended tests")
class BFDAuthOnOffTestCase(VppTestCase):
    """Bidirectional Forwarding Detection (BFD) (changing auth) """

    pg0 = None
    vpp_session = None
    test_session = None

    @classmethod
    def setUpClass(cls):
        super(BFDAuthOnOffTestCase, cls).setUpClass()
        try:
            cls.create_pg_interfaces([0])
            cls.pg0.config_ip4()
            cls.pg0.admin_up()
            cls.pg0.resolve_arp()

        except Exception:
            super(BFDAuthOnOffTestCase, cls).tearDownClass()
            raise

    def setUp(self):
        super(BFDAuthOnOffTestCase, self).setUp()
        self.factory = AuthKeyFactory()
        self.vapi.want_bfd_events()
        self.pg0.enable_capture()

    def tearDown(self):
        if not self.vpp_dead:
            self.vapi.want_bfd_events(enable_disable=0)
        self.vapi.collect_events()  # clear the event queue
        super(BFDAuthOnOffTestCase, self).tearDown()

    def test_auth_on_immediate(self):
        """ turn auth on without disturbing session state (immediate) """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4)
        self.vpp_session.add_vpp_config()
        self.test_session = BFDTestSession(self, self.pg0, AF_INET)
        bfd_session_up(self)
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.vpp_session.activate_auth(key)
        self.test_session.bfd_key_id = self.vpp_session.bfd_key_id
        self.test_session.sha1_key = key
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")

    def test_auth_off_immediate(self):
        """ turn auth off without disturbing session state (immediate) """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4, sha1_key=key)
        self.vpp_session.add_vpp_config()
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=self.vpp_session.bfd_key_id)
        bfd_session_up(self)
        # self.vapi.want_bfd_events(enable_disable=0)
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.inc_seq_num()
            self.test_session.send_packet()
        self.vpp_session.deactivate_auth()
        self.test_session.bfd_key_id = None
        self.test_session.sha1_key = None
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.inc_seq_num()
            self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")

    def test_auth_change_key_immediate(self):
        """ change auth key without disturbing session state (immediate) """
        key1 = self.factory.create_random_key(self)
        key1.add_vpp_config()
        key2 = self.factory.create_random_key(self)
        key2.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4, sha1_key=key1)
        self.vpp_session.add_vpp_config()
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key1,
            bfd_key_id=self.vpp_session.bfd_key_id)
        bfd_session_up(self)
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.vpp_session.activate_auth(key2)
        self.test_session.bfd_key_id = self.vpp_session.bfd_key_id
        self.test_session.sha1_key = key2
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")

    def test_auth_on_delayed(self):
        """ turn auth on without disturbing session state (delayed) """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4)
        self.vpp_session.add_vpp_config()
        self.test_session = BFDTestSession(self, self.pg0, AF_INET)
        bfd_session_up(self)
        for dummy in range(self.test_session.detect_mult * 2):
            wait_for_bfd_packet(self)
            self.test_session.send_packet()
        self.vpp_session.activate_auth(key, delayed=True)
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.test_session.bfd_key_id = self.vpp_session.bfd_key_id
        self.test_session.sha1_key = key
        self.test_session.send_packet()
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")

    def test_auth_off_delayed(self):
        """ turn auth off without disturbing session state (delayed) """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4, sha1_key=key)
        self.vpp_session.add_vpp_config()
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key,
            bfd_key_id=self.vpp_session.bfd_key_id)
        bfd_session_up(self)
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.vpp_session.deactivate_auth(delayed=True)
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.test_session.bfd_key_id = None
        self.test_session.sha1_key = None
        self.test_session.send_packet()
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")

    def test_auth_change_key_delayed(self):
        """ change auth key without disturbing session state (delayed) """
        key1 = self.factory.create_random_key(self)
        key1.add_vpp_config()
        key2 = self.factory.create_random_key(self)
        key2.add_vpp_config()
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip4, sha1_key=key1)
        self.vpp_session.add_vpp_config()
        self.vpp_session.admin_up()
        self.test_session = BFDTestSession(
            self, self.pg0, AF_INET, sha1_key=key1,
            bfd_key_id=self.vpp_session.bfd_key_id)
        bfd_session_up(self)
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.vpp_session.activate_auth(key2, delayed=True)
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.test_session.bfd_key_id = self.vpp_session.bfd_key_id
        self.test_session.sha1_key = key2
        self.test_session.send_packet()
        for dummy in range(self.test_session.detect_mult * 2):
            p = wait_for_bfd_packet(self)
            self.assert_equal(p[BFD].state, BFDState.up, BFDState)
            self.test_session.send_packet()
        self.assert_equal(self.vpp_session.state, BFDState.up, BFDState)
        self.assert_equal(len(self.vapi.collect_events()), 0,
                          "number of bfd events")


@unittest.skipUnless(running_extended_tests(), "part of extended tests")
class BFDCLITestCase(VppTestCase):
    """Bidirectional Forwarding Detection (BFD) (CLI) """
    pg0 = None

    @classmethod
    def setUpClass(cls):
        super(BFDCLITestCase, cls).setUpClass()

        try:
            cls.create_pg_interfaces((0,))
            cls.pg0.config_ip4()
            cls.pg0.config_ip6()
            cls.pg0.resolve_arp()
            cls.pg0.resolve_ndp()

        except Exception:
            super(BFDCLITestCase, cls).tearDownClass()
            raise

    def setUp(self):
        super(BFDCLITestCase, self).setUp()
        self.factory = AuthKeyFactory()
        self.pg0.enable_capture()

    def tearDown(self):
        try:
            self.vapi.want_bfd_events(enable_disable=0)
        except UnexpectedApiReturnValueError:
            # some tests aren't subscribed, so this is not an issue
            pass
        self.vapi.collect_events()  # clear the event queue
        super(BFDCLITestCase, self).tearDown()

    def cli_verify_no_response(self, cli):
        """ execute a CLI, asserting that the response is empty """
        self.assert_equal(self.vapi.cli(cli),
                          "",
                          "CLI command response")

    def cli_verify_response(self, cli, expected):
        """ execute a CLI, asserting that the response matches expectation """
        self.assert_equal(self.vapi.cli(cli).strip(),
                          expected,
                          "CLI command response")

    def test_show(self):
        """ show commands """
        k1 = self.factory.create_random_key(self)
        k1.add_vpp_config()
        k2 = self.factory.create_random_key(
            self, auth_type=BFDAuthType.meticulous_keyed_sha1)
        k2.add_vpp_config()
        s1 = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4)
        s1.add_vpp_config()
        s2 = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip6, af=AF_INET6,
                              sha1_key=k2)
        s2.add_vpp_config()
        self.logger.info(self.vapi.ppcli("show bfd keys"))
        self.logger.info(self.vapi.ppcli("show bfd sessions"))
        self.logger.info(self.vapi.ppcli("show bfd"))

    def test_set_del_sha1_key(self):
        """ set/delete SHA1 auth key """
        k = self.factory.create_random_key(self)
        self.registry.register(k, self.logger)
        self.cli_verify_no_response(
            "bfd key set conf-key-id %s type keyed-sha1 secret %s" %
            (k.conf_key_id,
                "".join("{:02x}".format(ord(c)) for c in k.key)))
        self.assertTrue(k.query_vpp_config())
        self.vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4, sha1_key=k)
        self.vpp_session.add_vpp_config()
        self.test_session = \
            BFDTestSession(self, self.pg0, AF_INET, sha1_key=k,
                           bfd_key_id=self.vpp_session.bfd_key_id)
        self.vapi.want_bfd_events()
        bfd_session_up(self)
        bfd_session_down(self)
        # try to replace the secret for the key - should fail because the key
        # is in-use
        k2 = self.factory.create_random_key(self)
        self.cli_verify_response(
            "bfd key set conf-key-id %s type keyed-sha1 secret %s" %
            (k.conf_key_id,
                "".join("{:02x}".format(ord(c)) for c in k2.key)),
            "bfd key set: `bfd_auth_set_key' API call failed, "
            "rv=-103:BFD object in use")
        # manipulating the session using old secret should still work
        bfd_session_up(self)
        bfd_session_down(self)
        self.vpp_session.remove_vpp_config()
        self.cli_verify_no_response(
            "bfd key del conf-key-id %s" % k.conf_key_id)
        self.assertFalse(k.query_vpp_config())

    def test_set_del_meticulous_sha1_key(self):
        """ set/delete meticulous SHA1 auth key """
        k = self.factory.create_random_key(
            self, auth_type=BFDAuthType.meticulous_keyed_sha1)
        self.registry.register(k, self.logger)
        self.cli_verify_no_response(
            "bfd key set conf-key-id %s type meticulous-keyed-sha1 secret %s" %
            (k.conf_key_id,
                "".join("{:02x}".format(ord(c)) for c in k.key)))
        self.assertTrue(k.query_vpp_config())
        self.vpp_session = VppBFDUDPSession(self, self.pg0,
                                            self.pg0.remote_ip6, af=AF_INET6,
                                            sha1_key=k)
        self.vpp_session.add_vpp_config()
        self.vpp_session.admin_up()
        self.test_session = \
            BFDTestSession(self, self.pg0, AF_INET6, sha1_key=k,
                           bfd_key_id=self.vpp_session.bfd_key_id)
        self.vapi.want_bfd_events()
        bfd_session_up(self)
        bfd_session_down(self)
        # try to replace the secret for the key - should fail because the key
        # is in-use
        k2 = self.factory.create_random_key(self)
        self.cli_verify_response(
            "bfd key set conf-key-id %s type keyed-sha1 secret %s" %
            (k.conf_key_id,
                "".join("{:02x}".format(ord(c)) for c in k2.key)),
            "bfd key set: `bfd_auth_set_key' API call failed, "
            "rv=-103:BFD object in use")
        # manipulating the session using old secret should still work
        bfd_session_up(self)
        bfd_session_down(self)
        self.vpp_session.remove_vpp_config()
        self.cli_verify_no_response(
            "bfd key del conf-key-id %s" % k.conf_key_id)
        self.assertFalse(k.query_vpp_config())

    def test_add_mod_del_bfd_udp(self):
        """ create/modify/delete IPv4 BFD UDP session """
        vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4)
        self.registry.register(vpp_session, self.logger)
        cli_add_cmd = "bfd udp session add interface %s local-addr %s " \
            "peer-addr %s desired-min-tx %s required-min-rx %s "\
            "detect-mult %s" % (self.pg0.name, self.pg0.local_ip4,
                                self.pg0.remote_ip4,
                                vpp_session.desired_min_tx,
                                vpp_session.required_min_rx,
                                vpp_session.detect_mult)
        self.cli_verify_no_response(cli_add_cmd)
        # 2nd add should fail
        self.cli_verify_response(
            cli_add_cmd,
            "bfd udp session add: `bfd_add_add_session' API call"
            " failed, rv=-101:Duplicate BFD object")
        verify_bfd_session_config(self, vpp_session)
        mod_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4,
            required_min_rx=2 * vpp_session.required_min_rx,
            desired_min_tx=3 * vpp_session.desired_min_tx,
            detect_mult=4 * vpp_session.detect_mult)
        self.cli_verify_no_response(
            "bfd udp session mod interface %s local-addr %s peer-addr %s "
            "desired-min-tx %s required-min-rx %s detect-mult %s" %
            (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4,
             mod_session.desired_min_tx, mod_session.required_min_rx,
             mod_session.detect_mult))
        verify_bfd_session_config(self, mod_session)
        cli_del_cmd = "bfd udp session del interface %s local-addr %s "\
            "peer-addr %s" % (self.pg0.name,
                              self.pg0.local_ip4, self.pg0.remote_ip4)
        self.cli_verify_no_response(cli_del_cmd)
        # 2nd del is expected to fail
        self.cli_verify_response(
            cli_del_cmd, "bfd udp session del: `bfd_udp_del_session' API call"
            " failed, rv=-102:No such BFD object")
        self.assertFalse(vpp_session.query_vpp_config())

    def test_add_mod_del_bfd_udp6(self):
        """ create/modify/delete IPv6 BFD UDP session """
        vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip6, af=AF_INET6)
        self.registry.register(vpp_session, self.logger)
        cli_add_cmd = "bfd udp session add interface %s local-addr %s " \
            "peer-addr %s desired-min-tx %s required-min-rx %s "\
            "detect-mult %s" % (self.pg0.name, self.pg0.local_ip6,
                                self.pg0.remote_ip6,
                                vpp_session.desired_min_tx,
                                vpp_session.required_min_rx,
                                vpp_session.detect_mult)
        self.cli_verify_no_response(cli_add_cmd)
        # 2nd add should fail
        self.cli_verify_response(
            cli_add_cmd,
            "bfd udp session add: `bfd_add_add_session' API call"
            " failed, rv=-101:Duplicate BFD object")
        verify_bfd_session_config(self, vpp_session)
        mod_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip6, af=AF_INET6,
            required_min_rx=2 * vpp_session.required_min_rx,
            desired_min_tx=3 * vpp_session.desired_min_tx,
            detect_mult=4 * vpp_session.detect_mult)
        self.cli_verify_no_response(
            "bfd udp session mod interface %s local-addr %s peer-addr %s "
            "desired-min-tx %s required-min-rx %s detect-mult %s" %
            (self.pg0.name, self.pg0.local_ip6, self.pg0.remote_ip6,
             mod_session.desired_min_tx,
             mod_session.required_min_rx, mod_session.detect_mult))
        verify_bfd_session_config(self, mod_session)
        cli_del_cmd = "bfd udp session del interface %s local-addr %s "\
            "peer-addr %s" % (self.pg0.name,
                              self.pg0.local_ip6, self.pg0.remote_ip6)
        self.cli_verify_no_response(cli_del_cmd)
        # 2nd del is expected to fail
        self.cli_verify_response(
            cli_del_cmd,
            "bfd udp session del: `bfd_udp_del_session' API call"
            " failed, rv=-102:No such BFD object")
        self.assertFalse(vpp_session.query_vpp_config())

    def test_add_mod_del_bfd_udp_auth(self):
        """ create/modify/delete IPv4 BFD UDP session (authenticated) """
        key = self.factory.create_random_key(self)
        key.add_vpp_config()
        vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4, sha1_key=key)
        self.registry.register(vpp_session, self.logger)
        cli_add_cmd = "bfd udp session add interface %s local-addr %s " \
            "peer-addr %s desired-min-tx %s required-min-rx %s "\
            "detect-mult %s conf-key-id %s bfd-key-id %s"\
            % (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4,
               vpp_session.desired_min_tx, vpp_session.required_min_rx,
               vpp_session.detect_mult, key.conf_key_id,
               vpp_session.bfd_key_id)
        self.cli_verify_no_response(cli_add_cmd)
        # 2nd add should fail
        self.cli_verify_response(
            cli_add_cmd,
            "bfd udp session add: `bfd_add_add_session' API call"
            " failed, rv=-101:Duplicate BFD object")
        verify_bfd_session_config(self, vpp_session)
        mod_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip4, sha1_key=key,
            bfd_key_id=vpp_session.bfd_key_id,
            required_min_rx=2 * vpp_session.required_min_rx,
            desired_min_tx=3 * vpp_session.desired_min_tx,
            detect_mult=4 * vpp_session.detect_mult)
        self.cli_verify_no_response(
            "bfd udp session mod interface %s local-addr %s peer-addr %s "
            "desired-min-tx %s required-min-rx %s detect-mult %s" %
            (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4,
             mod_session.desired_min_tx,
             mod_session.required_min_rx, mod_session.detect_mult))
        verify_bfd_session_config(self, mod_session)
        cli_del_cmd = "bfd udp session del interface %s local-addr %s "\
            "peer-addr %s" % (self.pg0.name,
                              self.pg0.local_ip4, self.pg0.remote_ip4)
        self.cli_verify_no_response(cli_del_cmd)
        # 2nd del is expected to fail
        self.cli_verify_response(
            cli_del_cmd,
            "bfd udp session del: `bfd_udp_del_session' API call"
            " failed, rv=-102:No such BFD object")
        self.assertFalse(vpp_session.query_vpp_config())

    def test_add_mod_del_bfd_udp6_auth(self):
        """ create/modify/delete IPv6 BFD UDP session (authenticated) """
        key = self.factory.create_random_key(
            self, auth_type=BFDAuthType.meticulous_keyed_sha1)
        key.add_vpp_config()
        vpp_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip6, af=AF_INET6, sha1_key=key)
        self.registry.register(vpp_session, self.logger)
        cli_add_cmd = "bfd udp session add interface %s local-addr %s " \
            "peer-addr %s desired-min-tx %s required-min-rx %s "\
            "detect-mult %s conf-key-id %s bfd-key-id %s" \
            % (self.pg0.name, self.pg0.local_ip6, self.pg0.remote_ip6,
               vpp_session.desired_min_tx, vpp_session.required_min_rx,
               vpp_session.detect_mult, key.conf_key_id,
               vpp_session.bfd_key_id)
        self.cli_verify_no_response(cli_add_cmd)
        # 2nd add should fail
        self.cli_verify_response(
            cli_add_cmd,
            "bfd udp session add: `bfd_add_add_session' API call"
            " failed, rv=-101:Duplicate BFD object")
        verify_bfd_session_config(self, vpp_session)
        mod_session = VppBFDUDPSession(
            self, self.pg0, self.pg0.remote_ip6, af=AF_INET6, sha1_key=key,
            bfd_key_id=vpp_session.bfd_key_id,
            required_min_rx=2 * vpp_session.required_min_rx,
            desired_min_tx=3 * vpp_session.desired_min_tx,
            detect_mult=4 * vpp_session.detect_mult)
        self.cli_verify_no_response(
            "bfd udp session mod interface %s local-addr %s peer-addr %s "
            "desired-min-tx %s required-min-rx %s detect-mult %s" %
            (self.pg0.name, self.pg0.local_ip6, self.pg0.remote_ip6,
             mod_session.desired_min_tx,
             mod_session.required_min_rx, mod_session.detect_mult))
        verify_bfd_session_config(self, mod_session)
        cli_del_cmd = "bfd udp session del interface %s local-addr %s "\
            "peer-addr %s" % (self.pg0.name,
                              self.pg0.local_ip6, self.pg0.remote_ip6)
        self.cli_verify_no_response(cli_del_cmd)
        # 2nd del is expected to fail
        self.cli_verify_response(
            cli_del_cmd,
            "bfd udp session del: `bfd_udp_del_session' API call"
            " failed, rv=-102:No such BFD object")
        self.assertFalse(vpp_session.query_vpp_config())

    def test_auth_on_off(self):
        """ turn authentication on and off """
        key = self.factory.create_random_key(
            self, auth_type=BFDAuthType.meticulous_keyed_sha1)
        key.add_vpp_config()
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4)
        auth_session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4,
                                        sha1_key=key)
        session.add_vpp_config()
        cli_activate = \
            "bfd udp session auth activate interface %s local-addr %s "\
            "peer-addr %s conf-key-id %s bfd-key-id %s"\
            % (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4,
               key.conf_key_id, auth_session.bfd_key_id)
        self.cli_verify_no_response(cli_activate)
        verify_bfd_session_config(self, auth_session)
        self.cli_verify_no_response(cli_activate)
        verify_bfd_session_config(self, auth_session)
        cli_deactivate = \
            "bfd udp session auth deactivate interface %s local-addr %s "\
            "peer-addr %s "\
            % (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4)
        self.cli_verify_no_response(cli_deactivate)
        verify_bfd_session_config(self, session)
        self.cli_verify_no_response(cli_deactivate)
        verify_bfd_session_config(self, session)

    def test_auth_on_off_delayed(self):
        """ turn authentication on and off (delayed) """
        key = self.factory.create_random_key(
            self, auth_type=BFDAuthType.meticulous_keyed_sha1)
        key.add_vpp_config()
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4)
        auth_session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4,
                                        sha1_key=key)
        session.add_vpp_config()
        cli_activate = \
            "bfd udp session auth activate interface %s local-addr %s "\
            "peer-addr %s conf-key-id %s bfd-key-id %s delayed yes"\
            % (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4,
               key.conf_key_id, auth_session.bfd_key_id)
        self.cli_verify_no_response(cli_activate)
        verify_bfd_session_config(self, auth_session)
        self.cli_verify_no_response(cli_activate)
        verify_bfd_session_config(self, auth_session)
        cli_deactivate = \
            "bfd udp session auth deactivate interface %s local-addr %s "\
            "peer-addr %s delayed yes"\
            % (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4)
        self.cli_verify_no_response(cli_deactivate)
        verify_bfd_session_config(self, session)
        self.cli_verify_no_response(cli_deactivate)
        verify_bfd_session_config(self, session)

    def test_admin_up_down(self):
        """ put session admin-up and admin-down """
        session = VppBFDUDPSession(self, self.pg0, self.pg0.remote_ip4)
        session.add_vpp_config()
        cli_down = \
            "bfd udp session set-flags admin down interface %s local-addr %s "\
            "peer-addr %s "\
            % (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4)
        cli_up = \
            "bfd udp session set-flags admin up interface %s local-addr %s "\
            "peer-addr %s "\
            % (self.pg0.name, self.pg0.local_ip4, self.pg0.remote_ip4)
        self.cli_verify_no_response(cli_down)
        verify_bfd_session_config(self, session, state=BFDState.admin_down)
        self.cli_verify_no_response(cli_up)
        verify_bfd_session_config(self, session, state=BFDState.down)

    def test_set_del_udp_echo_source(self):
        """ set/del udp echo source """
        self.create_loopback_interfaces([0])
        self.loopback0 = self.lo_interfaces[0]
        self.loopback0.admin_up()
        self.cli_verify_response("show bfd echo-source",
                                 "UDP echo source is not set.")
        cli_set = "bfd udp echo-source set interface %s" % self.loopback0.name
        self.cli_verify_no_response(cli_set)
        self.cli_verify_response("show bfd echo-source",
                                 "UDP echo source is: %s\n"
                                 "IPv4 address usable as echo source: none\n"
                                 "IPv6 address usable as echo source: none" %
                                 self.loopback0.name)
        self.loopback0.config_ip4()
        unpacked = unpack("!L", self.loopback0.local_ip4n)
        echo_ip4 = inet_ntop(AF_INET, pack("!L", unpacked[0] ^ 1))
        self.cli_verify_response("show bfd echo-source",
                                 "UDP echo source is: %s\n"
                                 "IPv4 address usable as echo source: %s\n"
                                 "IPv6 address usable as echo source: none" %
                                 (self.loopback0.name, echo_ip4))
        unpacked = unpack("!LLLL", self.loopback0.local_ip6n)
        echo_ip6 = inet_ntop(AF_INET6, pack("!LLLL", unpacked[0], unpacked[1],
                                            unpacked[2], unpacked[3] ^ 1))
        self.loopback0.config_ip6()
        self.cli_verify_response("show bfd echo-source",
                                 "UDP echo source is: %s\n"
                                 "IPv4 address usable as echo source: %s\n"
                                 "IPv6 address usable as echo source: %s" %
                                 (self.loopback0.name, echo_ip4, echo_ip6))
        cli_del = "bfd udp echo-source del"
        self.cli_verify_no_response(cli_del)
        self.cli_verify_response("show bfd echo-source",
                                 "UDP echo source is not set.")

if __name__ == '__main__':
    unittest.main(testRunner=VppTestRunner)