1 /* $OpenBSD: tcpdrop.c,v 1.5 2006/01/03 01:46:27 stevesk 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 23 #include <netinet/in.h> 24 #include <netinet/tcp.h> 25 #include <netinet/ip_var.h> 26 #include <netinet/tcp_timer.h> 27 #include <netinet/tcp_var.h> 28 29 #include <err.h> 30 #include <stdio.h> 31 #include <string.h> 32 #include <stdlib.h> 33 #include <netdb.h> 34 35 extern char *__progname; 36 37 /* 38 * Drop a tcp connection. 39 */ 40 int 41 main(int argc, char **argv) 42 { 43 int mib[] = { CTL_NET, PF_INET, IPPROTO_TCP, TCPCTL_DROP }; 44 struct addrinfo hints, *ail, *aif, *laddr, *faddr; 45 char fhbuf[NI_MAXHOST], fsbuf[NI_MAXSERV]; 46 char lhbuf[NI_MAXHOST], lsbuf[NI_MAXSERV]; 47 struct tcp_ident_mapping tir; 48 int gaierr, rval = 0; 49 50 if (argc != 5) { 51 fprintf(stderr, "usage: %s laddr lport faddr fport\n", 52 __progname); 53 exit(1); 54 } 55 56 memset(&hints, 0, sizeof(hints)); 57 hints.ai_family = AF_UNSPEC; 58 hints.ai_socktype = SOCK_STREAM; 59 60 if ((gaierr = getaddrinfo(argv[1], argv[2], &hints, &laddr)) != 0) 61 errx(1, "%s port %s: %s", argv[1], argv[2], 62 gai_strerror(gaierr)); 63 64 if ((gaierr = getaddrinfo(argv[3], argv[4], &hints, &faddr)) != 0) { 65 freeaddrinfo(laddr); 66 errx(1, "%s port %s: %s", argv[3], argv[4], 67 gai_strerror(gaierr)); 68 } 69 70 for (ail = laddr; ail; ail = ail->ai_next) { 71 for (aif = faddr; aif; aif = aif->ai_next) { 72 if (ail->ai_family != aif->ai_family) 73 continue; 74 memcpy(&tir.faddr, aif->ai_addr, aif->ai_addrlen); 75 memcpy(&tir.laddr, ail->ai_addr, ail->ai_addrlen); 76 77 if ((gaierr = getnameinfo(aif->ai_addr, aif->ai_addrlen, 78 fhbuf, sizeof(fhbuf), 79 fsbuf, sizeof(fsbuf), 80 NI_NUMERICHOST | NI_NUMERICSERV)) != 0) 81 errx(1, "getnameinfo: %s", gai_strerror(gaierr)); 82 if ((gaierr = getnameinfo(ail->ai_addr, ail->ai_addrlen, 83 lhbuf, sizeof(lhbuf), 84 lsbuf, sizeof(lsbuf), 85 NI_NUMERICHOST | NI_NUMERICSERV)) != 0) 86 errx(1, "getnameinfo: %s", gai_strerror(gaierr)); 87 88 if (sysctl(mib, sizeof (mib) / sizeof (int), NULL, 89 NULL, &tir, sizeof(tir)) == -1) { 90 rval = 1; 91 warn("%s %s %s %s", lhbuf, lsbuf, fhbuf, fsbuf); 92 } else 93 printf("%s %s %s %s: dropped\n", 94 lhbuf, lsbuf, fhbuf, fsbuf); 95 96 } 97 } 98 freeaddrinfo(laddr); 99 freeaddrinfo(faddr); 100 exit(rval); 101 } 102