freebsd-dev/lib/libpcap/pcap-snoop.c
1995-01-20 04:13:07 +00:00

196 lines
5.0 KiB
C

/*
* Copyright (c) 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#ifndef lint
static char rcsid[] =
"@(#)$Header: pcap-snoop.c,v 1.6 94/01/31 05:26:09 leres Exp $ (LBL)";
#endif
#include <sys/param.h>
#include <stdio.h>
#include <netdb.h>
#include <ctype.h>
#include <signal.h>
#include <errno.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <net/raw.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/if_ether.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/tcp.h>
#include <netinet/tcpip.h>
#include <net/bpf.h>
#include "pcap-int.h"
static int hdrpad; /* XXX */
int
pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
int cc;
register struct snoopheader *sh;
register int datalen;
register int caplen;
register u_char *cp;
again:
cc = read(p->fd, (char *)p->buffer, p->bufsize);
if (cc < 0) {
switch (errno) {
case EWOULDBLOCK:
return (0); /* XXX */
}
sprintf(p->errbuf, "read: %s", pcap_strerror(errno));
return (-1);
}
sh = (struct snoopheader *)p->buffer;
datalen = sh->snoop_packetlen;
caplen = (datalen < p->snapshot) ? datalen : p->snapshot;
cp = (u_char *)(sh + 1) + hdrpad; /* XXX */
if (p->fcode.bf_insns == NULL ||
bpf_filter(p->fcode.bf_insns, cp, datalen, caplen)) {
struct pcap_pkthdr h;
++p->md.stat.ps_recv;
h.ts = sh->snoop_timestamp;
h.len = datalen;
h.caplen = caplen;
(*callback)(user, &h, cp);
return (1);
}
return (0);
}
int
pcap_stats(pcap_t *p, struct pcap_stat *ps)
{
register struct rawstats *rs;
struct rawstats rawstats;
rs = &rawstats;
bzero((char *)rs, sizeof(*rs));
if (ioctl(p->fd, SIOCRAWSTATS, (char *)rs) < 0) {
sprintf(p->errbuf, "SIOCRAWSTATS: %s", pcap_strerror(errno));
return (-1);
}
p->md.stat.ps_drop =
rs->rs_snoop.ss_ifdrops + rs->rs_snoop.ss_sbdrops +
rs->rs_drain.ds_ifdrops + rs->rs_drain.ds_sbdrops;
*ps = p->md.stat;
return (0);
}
/* XXX can't disable promiscuous */
pcap_t *
pcap_open_live(char *device, int snaplen, int promisc, int to_ms, char *ebuf)
{
pcap_t *p;
struct sockaddr_raw sr;
int fd;
int v;
struct snoopfilter sf;
p = (pcap_t *)malloc(sizeof(*p));
if (p == NULL) {
strcpy(ebuf, "no swap");
return (0);
}
bzero(p, sizeof(*p));
p->fd = -1;
p->bufsize = 4096; /* XXX */
p->buffer = (u_char *)malloc(p->bufsize);
if (p->buffer == NULL) {
strcpy(ebuf, "no swap");
goto bad;
}
fd = p->fd = socket(PF_RAW, SOCK_RAW, RAWPROTO_SNOOP);
if (fd < 0) {
sprintf(ebuf, "snoop socket: %s", pcap_strerror(errno));
goto bad;
}
sr.sr_family = AF_RAW;
sr.sr_port = 0;
(void)strncpy(sr.sr_ifname, device, sizeof(sr.sr_ifname));
if (bind(fd, (struct sockaddr *)&sr, sizeof(sr))) {
sprintf(ebuf, "snoop bind: %s", pcap_strerror(errno));
goto bad;
}
bzero((char *)&sf, sizeof(sf));
if (ioctl(fd, SIOCADDSNOOP, &sf) < 0) {
sprintf(ebuf, "SIOCADDSNOOP: %s", pcap_strerror(errno));
goto bad;
}
v = 64 * 1024;
(void)setsockopt(fd, SOL_SOCKET, SO_RCVBUF, (char *)&v, sizeof(v));
if (ioctl(fd, SIOCSNOOPLEN, &snaplen) < 0) {
sprintf(ebuf, "SIOCSNOOPLEN: %s", pcap_strerror(errno));
goto bad;
}
p->snapshot = snaplen;
v = 1;
if (ioctl(fd, SIOCSNOOPING, &v) < 0) {
sprintf(ebuf, "SIOCSNOOPING: %s", pcap_strerror(errno));
goto bad;
}
/*
* XXX hack - map device name to link later type
*/
if (strncmp("et", device, 2) == 0 ||
strncmp("ec", device, 2) == 0) {
p->linktype = DLT_EN10MB;
hdrpad = RAW_HDRPAD(sizeof(struct ether_header));
} else if (strncmp("ipg", device, 3) == 0 ||
strncmp("xpi", device, 3) == 0) {
p->linktype = DLT_FDDI;
hdrpad = 3; /* XXX yeah? */
} else {
sprintf(ebuf, "snoop: unknown physical layer type");
goto bad;
}
return (p);
bad:
if (fd >= 0)
close(fd);
if (p->buffer != NULL)
free(p->buffer);
free(p);
return (0);
}
int
pcap_setfilter(pcap_t *p, struct bpf_program *fp)
{
p->fcode = *fp;
return (0);
}