1 /* $OpenBSD: tcpdrop.c,v 1.9 2012/12/18 21:28:45 millert Exp $ */ 2 3 /* 4 * Copyright (c) 2004 Markus Friedl <markus@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/param.h> 20 #include <sys/socket.h> 21 #include <sys/sysctl.h> 22 #include <sys/timeout.h> 23 24 #include <netinet/in.h> 25 #include <netinet/tcp.h> 26 #include <netinet/ip_var.h> 27 #include <netinet/tcp_timer.h> 28 #include <netinet/tcp_var.h> 29 30 #include <err.h> 31 #include <stdio.h> 32 #include <string.h> 33 #include <stdlib.h> 34 #include <netdb.h> 35 36 extern char *__progname; 37 38 /* 39 * Drop a tcp connection. 40 */ 41 int 42 main(int argc, char **argv) 43 { 44 int mib[] = { CTL_NET, PF_INET, IPPROTO_TCP, TCPCTL_DROP }; 45 struct addrinfo hints, *ail, *aif, *laddr, *faddr; 46 char fhbuf[NI_MAXHOST], fsbuf[NI_MAXSERV]; 47 char lhbuf[NI_MAXHOST], lsbuf[NI_MAXSERV]; 48 char *laddr1, *addr1, *port1, *laddr2, *addr2, *port2; 49 struct tcp_ident_mapping tir; 50 int gaierr, rval = 0; 51 52 memset(&hints, 0, sizeof(hints)); 53 hints.ai_family = AF_UNSPEC; 54 hints.ai_socktype = SOCK_STREAM; 55 56 if (argc == 3) { 57 laddr1 = addr1 = strdup(argv[1]); 58 port1 = strrchr(addr1, ':'); 59 if (port1) 60 *port1++ = '\0'; 61 else 62 goto fail; 63 64 laddr2 = addr2 = strdup(argv[2]); 65 port2 = strrchr(addr2, ':'); 66 if (port2) 67 *port2++ = '\0'; 68 else 69 goto fail; 70 } else if (argc == 5) { 71 laddr1 = addr1 = argv[1]; 72 port1 = argv[2]; 73 laddr2 = addr2 = argv[3]; 74 port2 = argv[4]; 75 } else { 76 fail: 77 fprintf(stderr, 78 "usage: %s local-addr local-port remote-addr remote-port\n", 79 __progname); 80 fprintf(stderr, 81 " %s local-addr:local-port remote-addr:remote-port\n", 82 __progname); 83 exit(1); 84 } 85 86 if (addr1[0] == '[' && addr1[strlen(addr1) - 1] == ']') { 87 laddr1 = strdup(addr1); 88 laddr1[strlen(laddr1) - 1] = '\0'; 89 laddr1++; 90 } 91 if (addr2[0] == '[' && addr2[strlen(addr2) - 1] == ']') { 92 laddr2 = strdup(addr2); 93 laddr2[strlen(laddr2) - 1] = '\0'; 94 laddr2++; 95 } 96 97 if ((gaierr = getaddrinfo(laddr1, port1, &hints, &laddr)) != 0) 98 errx(1, "%s port %s: %s", addr1, port1, 99 gai_strerror(gaierr)); 100 101 if ((gaierr = getaddrinfo(laddr2, port2, &hints, &faddr)) != 0) { 102 freeaddrinfo(laddr); 103 errx(1, "%s port %s: %s", addr2, port2, 104 gai_strerror(gaierr)); 105 } 106 107 for (ail = laddr; ail; ail = ail->ai_next) { 108 for (aif = faddr; aif; aif = aif->ai_next) { 109 if (ail->ai_family != aif->ai_family) 110 continue; 111 memset(&tir, 0, sizeof(tir)); 112 memcpy(&tir.faddr, aif->ai_addr, aif->ai_addrlen); 113 memcpy(&tir.laddr, ail->ai_addr, ail->ai_addrlen); 114 115 if ((gaierr = getnameinfo(aif->ai_addr, aif->ai_addrlen, 116 fhbuf, sizeof(fhbuf), fsbuf, sizeof(fsbuf), 117 NI_NUMERICHOST | NI_NUMERICSERV)) != 0) 118 errx(1, "getnameinfo: %s", gai_strerror(gaierr)); 119 if ((gaierr = getnameinfo(ail->ai_addr, ail->ai_addrlen, 120 lhbuf, sizeof(lhbuf), lsbuf, sizeof(lsbuf), 121 NI_NUMERICHOST | NI_NUMERICSERV)) != 0) 122 errx(1, "getnameinfo: %s", gai_strerror(gaierr)); 123 124 if (sysctl(mib, sizeof (mib) / sizeof (int), NULL, 125 NULL, &tir, sizeof(tir)) == -1) { 126 rval = 1; 127 warn("%s %s %s %s", lhbuf, lsbuf, fhbuf, fsbuf); 128 } else { 129 if (aif->ai_family == PF_INET6) 130 printf("[%s]:%s [%s]:%s dropped\n", 131 lhbuf, lsbuf, fhbuf, fsbuf); 132 else 133 printf("%s:%s %s:%s dropped\n", 134 lhbuf, lsbuf, fhbuf, fsbuf); 135 } 136 } 137 } 138 freeaddrinfo(laddr); 139 freeaddrinfo(faddr); 140 exit(rval); 141 } 142