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/* $OpenBSD: tcpdrop.c,v 1.4 2004/05/22 23:55:22 deraadt Exp $ */
/*-
* Copyright (c) 2004 Markus Friedl <markus@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <netinet/in.h>
#include <netinet/tcp_var.h>
#include <err.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* Drop a tcp connection.
*/
int
main(int argc, char *argv[])
{
struct addrinfo hints, *ail, *aif, *laddr, *faddr;
/* addrs[0] is a foreign socket, addrs[1] is a local one. */
struct sockaddr_storage addrs[2];
int mib[] = { CTL_NET, PF_INET, IPPROTO_TCP, TCPCTL_DROP };
int gaierr, rval = 0;
char fhbuf[NI_MAXHOST], fsbuf[NI_MAXSERV], lhbuf[NI_MAXHOST],
lsbuf[NI_MAXSERV];
if (argc != 5)
errx(1, "usage: tcpdrop laddr lport faddr fport\n");
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
if ((gaierr = getaddrinfo(argv[1], argv[2], &hints, &laddr)) != 0)
errx(1, "%s port %s: %s", argv[1], argv[2],
gai_strerror(gaierr));
if ((gaierr = getaddrinfo(argv[3], argv[4], &hints, &faddr)) != 0) {
freeaddrinfo(laddr);
errx(1, "%s port %s: %s", argv[3], argv[4],
gai_strerror(gaierr));
}
for (ail = laddr; ail; ail = ail->ai_next) {
for (aif = faddr; aif; aif = aif->ai_next) {
if (ail->ai_family != aif->ai_family)
continue;
memcpy(&addrs[0], aif->ai_addr, aif->ai_addrlen);
memcpy(&addrs[1], ail->ai_addr, ail->ai_addrlen);
if (getnameinfo(aif->ai_addr, aif->ai_addrlen,
fhbuf, sizeof(fhbuf),
fsbuf, sizeof(fsbuf),
NI_NUMERICHOST | NI_NUMERICSERV) == -1)
err(1, "getnameinfo");
if (getnameinfo(ail->ai_addr, ail->ai_addrlen,
lhbuf, sizeof(lhbuf),
lsbuf, sizeof(lsbuf),
NI_NUMERICHOST | NI_NUMERICSERV) == -1)
err(1, "getnameinfo");
if (sysctl(mib, sizeof (mib) / sizeof (int), NULL,
NULL, &addrs, sizeof(addrs)) == -1) {
rval = 1;
warn("%s %s %s %s", lhbuf, lsbuf, fhbuf, fsbuf);
} else
printf("%s %s %s %s: dropped\n",
lhbuf, lsbuf, fhbuf, fsbuf);
}
}
freeaddrinfo(laddr);
freeaddrinfo(faddr);
exit(rval);
}
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