1 /* $OpenBSD: tcpdrop.c,v 1.4 2004/05/22 23:55:22 deraadt Exp $ */
4 * Copyright (c) 2009 Juli Mallett <jmallett@FreeBSD.org>
5 * Copyright (c) 2004 Markus Friedl <markus@openbsd.org>
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20 #include <sys/cdefs.h>
21 __FBSDID("$FreeBSD$");
23 #include <sys/param.h>
24 #include <sys/types.h>
25 #include <sys/socket.h>
26 #include <sys/socketvar.h>
27 #include <sys/sysctl.h>
29 #include <netinet/in.h>
30 #include <netinet/in_pcb.h>
32 #include <netinet/tcp_fsm.h>
33 #include <netinet/tcp_var.h>
43 #define TCPDROP_FOREIGN 0
44 #define TCPDROP_LOCAL 1
47 char hs_host[NI_MAXHOST];
48 char hs_service[NI_MAXSERV];
51 static bool tcpdrop_list_commands = false;
53 static char *findport(const char *);
54 static struct xinpgen *getxpcblist(const char *);
55 static void sockinfo(const struct sockaddr *, struct host_service *);
56 static bool tcpdrop(const struct sockaddr *, const struct sockaddr *);
57 static bool tcpdropall(void);
58 static bool tcpdropbyname(const char *, const char *, const char *,
60 static bool tcpdropconn(const struct in_conninfo *);
61 static void usage(void);
64 * Drop a tcp connection.
67 main(int argc, char *argv[])
75 while ((ch = getopt(argc, argv, "al")) != -1) {
81 tcpdrop_list_commands = true;
98 if ((argc != 2 && argc != 4) || tcpdrop_list_commands)
102 lport = findport(argv[0]);
103 fport = findport(argv[1]);
104 if (lport == NULL || lport[1] == '\0' || fport == NULL ||
109 if (!tcpdropbyname(argv[0], lport, argv[1], fport))
111 } else if (!tcpdropbyname(argv[0], argv[1], argv[2], argv[3]))
118 findport(const char *arg)
122 /* A strrspn() or strrpbrk() would be nice. */
123 dot = strrchr(arg, '.');
124 colon = strrchr(arg, ':');
135 static struct xinpgen *
136 getxpcblist(const char *name)
138 struct xinpgen *xinp;
143 rv = sysctlbyname(name, NULL, &len, NULL, 0);
145 err(1, "sysctlbyname %s", name);
148 errx(1, "%s is empty", name);
152 errx(1, "malloc failed");
154 rv = sysctlbyname(name, xinp, &len, NULL, 0);
156 err(1, "sysctlbyname %s", name);
162 sockinfo(const struct sockaddr *sa, struct host_service *hs)
164 static const int flags = NI_NUMERICHOST | NI_NUMERICSERV;
167 rv = getnameinfo(sa, sa->sa_len, hs->hs_host, sizeof hs->hs_host,
168 hs->hs_service, sizeof hs->hs_service, flags);
170 err(1, "getnameinfo");
174 tcpdrop(const struct sockaddr *lsa, const struct sockaddr *fsa)
176 struct host_service local, foreign;
177 struct sockaddr_storage addrs[2];
180 memcpy(&addrs[TCPDROP_FOREIGN], fsa, fsa->sa_len);
181 memcpy(&addrs[TCPDROP_LOCAL], lsa, lsa->sa_len);
183 sockinfo(lsa, &local);
184 sockinfo(fsa, &foreign);
186 if (tcpdrop_list_commands) {
187 printf("tcpdrop %s %s %s %s\n", local.hs_host, local.hs_service,
188 foreign.hs_host, foreign.hs_service);
192 rv = sysctlbyname("net.inet.tcp.drop", NULL, NULL, &addrs,
195 warn("%s %s %s %s", local.hs_host, local.hs_service,
196 foreign.hs_host, foreign.hs_service);
199 printf("%s %s %s %s: dropped\n", local.hs_host, local.hs_service,
200 foreign.hs_host, foreign.hs_service);
207 struct xinpgen *head, *xinp;
214 head = getxpcblist("net.inet.tcp.pcblist");
216 #define XINP_NEXT(xinp) \
217 ((struct xinpgen *)((uintptr_t)(xinp) + (xinp)->xig_len))
219 for (xinp = XINP_NEXT(head); xinp->xig_len > sizeof *xinp;
220 xinp = XINP_NEXT(xinp)) {
221 xtp = (struct xtcpcb *)xinp;
226 * Check protocol, support just v4 or v6, etc.
229 /* Ignore PCBs which were freed during copyout. */
230 if (xip->inp_gencnt > head->xig_gen)
233 /* Skip listening sockets. */
234 if (xtp->t_state == TCPS_LISTEN)
237 if (!tcpdropconn(&xip->inp_inc))
246 tcpdropbyname(const char *lhost, const char *lport, const char *fhost,
249 static const struct addrinfo hints = {
251 * Look for streams in all domains.
253 .ai_family = AF_UNSPEC,
254 .ai_socktype = SOCK_STREAM,
256 struct addrinfo *ail, *local, *aif, *foreign;
260 error = getaddrinfo(lhost, lport, &hints, &local);
262 errx(1, "getaddrinfo: %s port %s: %s", lhost, lport,
263 gai_strerror(error));
265 error = getaddrinfo(fhost, fport, &hints, &foreign);
267 freeaddrinfo(local); /* XXX gratuitous */
268 errx(1, "getaddrinfo: %s port %s: %s", fhost, fport,
269 gai_strerror(error));
276 * Try every combination of local and foreign address pairs.
278 for (ail = local; ail != NULL; ail = ail->ai_next) {
279 for (aif = foreign; aif != NULL; aif = aif->ai_next) {
280 if (ail->ai_family != aif->ai_family)
283 if (!tcpdrop(ail->ai_addr, aif->ai_addr))
289 warnx("%s %s %s %s: different address families", lhost, lport,
295 freeaddrinfo(foreign);
301 tcpdropconn(const struct in_conninfo *inc)
303 struct sockaddr *local, *foreign;
304 struct sockaddr_in6 sin6[2];
305 struct sockaddr_in sin4[2];
307 if ((inc->inc_flags & INC_ISIPV6) != 0) {
308 memset(sin6, 0, sizeof sin6);
310 sin6[TCPDROP_LOCAL].sin6_len = sizeof sin6[TCPDROP_LOCAL];
311 sin6[TCPDROP_LOCAL].sin6_family = AF_INET6;
312 sin6[TCPDROP_LOCAL].sin6_port = inc->inc_lport;
313 memcpy(&sin6[TCPDROP_LOCAL].sin6_addr, &inc->inc6_laddr,
314 sizeof inc->inc6_laddr);
315 local = (struct sockaddr *)&sin6[TCPDROP_LOCAL];
317 sin6[TCPDROP_FOREIGN].sin6_len = sizeof sin6[TCPDROP_FOREIGN];
318 sin6[TCPDROP_FOREIGN].sin6_family = AF_INET6;
319 sin6[TCPDROP_FOREIGN].sin6_port = inc->inc_fport;
320 memcpy(&sin6[TCPDROP_FOREIGN].sin6_addr, &inc->inc6_faddr,
321 sizeof inc->inc6_faddr);
322 foreign = (struct sockaddr *)&sin6[TCPDROP_FOREIGN];
324 memset(sin4, 0, sizeof sin4);
326 sin4[TCPDROP_LOCAL].sin_len = sizeof sin4[TCPDROP_LOCAL];
327 sin4[TCPDROP_LOCAL].sin_family = AF_INET;
328 sin4[TCPDROP_LOCAL].sin_port = inc->inc_lport;
329 memcpy(&sin4[TCPDROP_LOCAL].sin_addr, &inc->inc_laddr,
330 sizeof inc->inc_laddr);
331 local = (struct sockaddr *)&sin4[TCPDROP_LOCAL];
333 sin4[TCPDROP_FOREIGN].sin_len = sizeof sin4[TCPDROP_FOREIGN];
334 sin4[TCPDROP_FOREIGN].sin_family = AF_INET;
335 sin4[TCPDROP_FOREIGN].sin_port = inc->inc_fport;
336 memcpy(&sin4[TCPDROP_FOREIGN].sin_addr, &inc->inc_faddr,
337 sizeof inc->inc_faddr);
338 foreign = (struct sockaddr *)&sin4[TCPDROP_FOREIGN];
341 return (tcpdrop(local, foreign));
348 "usage: tcpdrop local-address local-port foreign-address foreign-port\n"
349 " tcpdrop local-address:local-port foreign-address:foreign-port\n"
350 " tcpdrop local-address.local-port foreign-address.foreign-port\n"
351 " tcpdrop [-l] -a\n");