247 lines
6.6 KiB
C
247 lines
6.6 KiB
C
/*
|
|
* Copyright (c) 1994, 1995, 1996, 1997, 1998
|
|
* 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 the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the Computer Systems
|
|
* Engineering Group at Lawrence Berkeley Laboratory.
|
|
* 4. Neither the name of the University nor of the Laboratory may be used
|
|
* to endorse or promote products derived from this software without
|
|
* specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static const char rcsid[] =
|
|
"@(#) $Header: /tcpdump/master/libpcap/inet.c,v 1.26 2000/01/14 23:55:31 mcr Exp $ (LBL)";
|
|
#endif
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/file.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/socket.h>
|
|
#ifdef HAVE_SYS_SOCKIO_H
|
|
#include <sys/sockio.h>
|
|
#endif
|
|
#include <sys/time.h> /* concession to AIX */
|
|
|
|
#if __STDC__
|
|
struct mbuf;
|
|
struct rtentry;
|
|
#endif
|
|
|
|
#include <net/if.h>
|
|
#include <netinet/in.h>
|
|
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <memory.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include "pcap-int.h"
|
|
|
|
#include "gnuc.h"
|
|
#ifdef HAVE_OS_PROTO_H
|
|
#include "os-proto.h"
|
|
#endif
|
|
|
|
/* Not all systems have IFF_LOOPBACK */
|
|
#ifdef IFF_LOOPBACK
|
|
#define ISLOOPBACK(p) ((p)->ifr_flags & IFF_LOOPBACK)
|
|
#else
|
|
#define ISLOOPBACK(p) ((p)->ifr_name[0] == 'l' && (p)->ifr_name[1] == 'o' && \
|
|
(isdigit((p)->ifr_name[2]) || (p)->ifr_name[2] == '\0'))
|
|
#endif
|
|
|
|
/*
|
|
* Return the name of a network interface attached to the system, or NULL
|
|
* if none can be found. The interface must be configured up; the
|
|
* lowest unit number is preferred; loopback is ignored.
|
|
*/
|
|
char *
|
|
pcap_lookupdev(errbuf)
|
|
register char *errbuf;
|
|
{
|
|
register int fd, minunit, n;
|
|
register char *cp;
|
|
register struct ifreq *ifrp, *ifend, *ifnext, *mp;
|
|
struct ifconf ifc;
|
|
char *buf;
|
|
struct ifreq ifr;
|
|
static char device[sizeof(ifrp->ifr_name) + 1];
|
|
unsigned buf_size;
|
|
|
|
fd = socket(AF_INET, SOCK_DGRAM, 0);
|
|
if (fd < 0) {
|
|
(void)sprintf(errbuf, "socket: %s", pcap_strerror(errno));
|
|
return (NULL);
|
|
}
|
|
|
|
buf_size = 8192;
|
|
|
|
for (;;) {
|
|
buf = malloc (buf_size);
|
|
if (buf == NULL) {
|
|
close (fd);
|
|
(void)sprintf(errbuf, "out of memory");
|
|
return (NULL);
|
|
}
|
|
|
|
ifc.ifc_len = buf_size;
|
|
ifc.ifc_buf = buf;
|
|
memset (buf, 0, buf_size);
|
|
if (ioctl(fd, SIOCGIFCONF, (char *)&ifc) < 0) {
|
|
free (buf);
|
|
(void)sprintf(errbuf, "SIOCGIFCONF: %s",
|
|
pcap_strerror(errno));
|
|
(void)close(fd);
|
|
return (NULL);
|
|
}
|
|
if (ifc.ifc_len < buf_size)
|
|
break;
|
|
free (buf);
|
|
buf_size *= 2;
|
|
}
|
|
|
|
ifrp = (struct ifreq *)buf;
|
|
ifend = (struct ifreq *)(buf + ifc.ifc_len);
|
|
|
|
mp = NULL;
|
|
minunit = 666;
|
|
for (; ifrp < ifend; ifrp = ifnext) {
|
|
#ifdef HAVE_SOCKADDR_SA_LEN
|
|
n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
|
|
if (n < sizeof(*ifrp))
|
|
ifnext = ifrp + 1;
|
|
else
|
|
ifnext = (struct ifreq *)((char *)ifrp + n);
|
|
if (ifrp->ifr_addr.sa_family != AF_INET)
|
|
continue;
|
|
#else
|
|
ifnext = ifrp + 1;
|
|
#endif
|
|
/*
|
|
* Need a template to preserve address info that is
|
|
* used below to locate the next entry. (Otherwise,
|
|
* SIOCGIFFLAGS stomps over it because the requests
|
|
* are returned in a union.)
|
|
*/
|
|
strncpy(ifr.ifr_name, ifrp->ifr_name, sizeof(ifr.ifr_name));
|
|
if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifr) < 0) {
|
|
if (errno == ENXIO)
|
|
continue;
|
|
(void)sprintf(errbuf, "SIOCGIFFLAGS: %.*s: %s",
|
|
(int)sizeof(ifr.ifr_name), ifr.ifr_name,
|
|
pcap_strerror(errno));
|
|
(void)close(fd);
|
|
free (buf);
|
|
return (NULL);
|
|
}
|
|
|
|
/* Must be up and not the loopback */
|
|
if ((ifr.ifr_flags & IFF_UP) == 0 || ISLOOPBACK(&ifr))
|
|
continue;
|
|
|
|
for (cp = ifrp->ifr_name; !isdigit(*cp); ++cp)
|
|
continue;
|
|
n = atoi(cp);
|
|
if (n < minunit) {
|
|
minunit = n;
|
|
mp = ifrp;
|
|
}
|
|
}
|
|
(void)close(fd);
|
|
if (mp == NULL) {
|
|
(void)strcpy(errbuf, "no suitable device found");
|
|
free(buf);
|
|
return (NULL);
|
|
}
|
|
|
|
(void)strncpy(device, mp->ifr_name, sizeof(device) - 1);
|
|
device[sizeof(device) - 1] = '\0';
|
|
free(buf);
|
|
return (device);
|
|
}
|
|
|
|
int
|
|
pcap_lookupnet(device, netp, maskp, errbuf)
|
|
register char *device;
|
|
register bpf_u_int32 *netp, *maskp;
|
|
register char *errbuf;
|
|
{
|
|
register int fd;
|
|
register struct sockaddr_in *sin;
|
|
struct ifreq ifr;
|
|
|
|
fd = socket(AF_INET, SOCK_DGRAM, 0);
|
|
if (fd < 0) {
|
|
(void)sprintf(errbuf, "socket: %s", pcap_strerror(errno));
|
|
return (-1);
|
|
}
|
|
memset(&ifr, 0, sizeof(ifr));
|
|
#ifdef linux
|
|
/* XXX Work around Linux kernel bug */
|
|
ifr.ifr_addr.sa_family = AF_INET;
|
|
#endif
|
|
(void)strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
|
|
if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) {
|
|
if (errno == EADDRNOTAVAIL) {
|
|
(void)sprintf(errbuf, "%s: no IPv4 address assigned",
|
|
device);
|
|
} else {
|
|
(void)sprintf(errbuf, "SIOCGIFADDR: %s: %s",
|
|
device, pcap_strerror(errno));
|
|
}
|
|
(void)close(fd);
|
|
return (-1);
|
|
}
|
|
sin = (struct sockaddr_in *)&ifr.ifr_addr;
|
|
*netp = sin->sin_addr.s_addr;
|
|
if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr) < 0) {
|
|
(void)sprintf(errbuf, "SIOCGIFNETMASK: %s: %s",
|
|
device, pcap_strerror(errno));
|
|
(void)close(fd);
|
|
return (-1);
|
|
}
|
|
(void)close(fd);
|
|
*maskp = sin->sin_addr.s_addr;
|
|
if (*maskp == 0) {
|
|
if (IN_CLASSA(*netp))
|
|
*maskp = IN_CLASSA_NET;
|
|
else if (IN_CLASSB(*netp))
|
|
*maskp = IN_CLASSB_NET;
|
|
else if (IN_CLASSC(*netp))
|
|
*maskp = IN_CLASSC_NET;
|
|
else {
|
|
(void)sprintf(errbuf, "inet class for 0x%x unknown",
|
|
*netp);
|
|
return (-1);
|
|
}
|
|
}
|
|
*netp &= *maskp;
|
|
return (0);
|
|
}
|