Home | History | Annotate | Download | only in libpcap
      1 /* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
      2 /*
      3  * Copyright (c) 1994, 1995, 1996, 1997, 1998
      4  *	The Regents of the University of California.  All rights reserved.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  * 3. All advertising materials mentioning features or use of this software
     15  *    must display the following acknowledgement:
     16  *	This product includes software developed by the Computer Systems
     17  *	Engineering Group at Lawrence Berkeley Laboratory.
     18  * 4. Neither the name of the University nor of the Laboratory may be used
     19  *    to endorse or promote products derived from this software without
     20  *    specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32  * SUCH DAMAGE.
     33  */
     34 
     35 #ifndef lint
     36 static const char rcsid[] _U_ =
     37     "@(#) $Header: /tcpdump/master/libpcap/fad-glifc.c,v 1.5.2.1 2005/04/19 00:54:16 guy Exp $ (LBL)";
     38 #endif
     39 
     40 #ifdef HAVE_CONFIG_H
     41 #include "config.h"
     42 #endif
     43 
     44 #include <sys/param.h>
     45 #include <sys/file.h>
     46 #include <sys/ioctl.h>
     47 #include <sys/socket.h>
     48 #ifdef HAVE_SYS_SOCKIO_H
     49 #include <sys/sockio.h>
     50 #endif
     51 #include <sys/time.h>				/* concession to AIX */
     52 
     53 struct mbuf;		/* Squelch compiler warnings on some platforms for */
     54 struct rtentry;		/* declarations in <net/if.h> */
     55 #include <net/if.h>
     56 #include <netinet/in.h>
     57 
     58 #include <ctype.h>
     59 #include <errno.h>
     60 #include <memory.h>
     61 #include <stdio.h>
     62 #include <stdlib.h>
     63 #include <string.h>
     64 #include <unistd.h>
     65 
     66 #include "pcap-int.h"
     67 
     68 #ifdef HAVE_OS_PROTO_H
     69 #include "os-proto.h"
     70 #endif
     71 
     72 /*
     73  * Get a list of all interfaces that are up and that we can open.
     74  * Returns -1 on error, 0 otherwise.
     75  * The list, as returned through "alldevsp", may be null if no interfaces
     76  * were up and could be opened.
     77  *
     78  * This is the implementation used on platforms that have SIOCLGIFCONF
     79  * but don't have "getifaddrs()".  (Solaris 8 and later; we use
     80  * SIOCLGIFCONF rather than SIOCGIFCONF in order to get IPv6 addresses.)
     81  */
     82 int
     83 pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
     84 {
     85 	pcap_if_t *devlist = NULL;
     86 	register int fd4, fd6, fd;
     87 	register struct lifreq *ifrp, *ifend;
     88 	struct lifnum ifn;
     89 	struct lifconf ifc;
     90 	char *buf = NULL;
     91 	unsigned buf_size;
     92 #ifdef HAVE_SOLARIS
     93 	char *p, *q;
     94 #endif
     95 	struct lifreq ifrflags, ifrnetmask, ifrbroadaddr, ifrdstaddr;
     96 	struct sockaddr *netmask, *broadaddr, *dstaddr;
     97 	int ret = 0;
     98 
     99 	/*
    100 	 * Create a socket from which to fetch the list of interfaces,
    101 	 * and from which to fetch IPv4 information.
    102 	 */
    103 	fd4 = socket(AF_INET, SOCK_DGRAM, 0);
    104 	if (fd4 < 0) {
    105 		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    106 		    "socket: %s", pcap_strerror(errno));
    107 		return (-1);
    108 	}
    109 
    110 	/*
    111 	 * Create a socket from which to fetch IPv6 information.
    112 	 */
    113 	fd6 = socket(AF_INET6, SOCK_DGRAM, 0);
    114 	if (fd6 < 0) {
    115 		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    116 		    "socket: %s", pcap_strerror(errno));
    117 		(void)close(fd4);
    118 		return (-1);
    119 	}
    120 
    121 	/*
    122 	 * How many entries will SIOCGLIFCONF return?
    123 	 */
    124 	ifn.lifn_family = AF_UNSPEC;
    125 	ifn.lifn_flags = 0;
    126 	ifn.lifn_count = 0;
    127 	if (ioctl(fd4, SIOCGLIFNUM, (char *)&ifn) < 0) {
    128 		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    129 		    "SIOCGLIFNUM: %s", pcap_strerror(errno));
    130 		(void)close(fd6);
    131 		(void)close(fd4);
    132 		return (-1);
    133 	}
    134 
    135 	/*
    136 	 * Allocate a buffer for those entries.
    137 	 */
    138 	buf_size = ifn.lifn_count * sizeof (struct lifreq);
    139 	buf = malloc(buf_size);
    140 	if (buf == NULL) {
    141 		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    142 		    "malloc: %s", pcap_strerror(errno));
    143 		(void)close(fd6);
    144 		(void)close(fd4);
    145 		return (-1);
    146 	}
    147 
    148 	/*
    149 	 * Get the entries.
    150 	 */
    151 	ifc.lifc_len = buf_size;
    152 	ifc.lifc_buf = buf;
    153 	ifc.lifc_family = AF_UNSPEC;
    154 	ifc.lifc_flags = 0;
    155 	memset(buf, 0, buf_size);
    156 	if (ioctl(fd4, SIOCGLIFCONF, (char *)&ifc) < 0) {
    157 		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    158 		    "SIOCGLIFCONF: %s", pcap_strerror(errno));
    159 		(void)close(fd6);
    160 		(void)close(fd4);
    161 		free(buf);
    162 		return (-1);
    163 	}
    164 
    165 	/*
    166 	 * Loop over the entries.
    167 	 */
    168 	ifrp = (struct lifreq *)buf;
    169 	ifend = (struct lifreq *)(buf + ifc.lifc_len);
    170 
    171 	for (; ifrp < ifend; ifrp++) {
    172 		/*
    173 		 * IPv6 or not?
    174 		 */
    175 		if (((struct sockaddr *)&ifrp->lifr_addr)->sa_family == AF_INET6)
    176 			fd = fd6;
    177 		else
    178 			fd = fd4;
    179 
    180 		/*
    181 		 * Skip entries that begin with "dummy".
    182 		 * XXX - what are these?  Is this Linux-specific?
    183 		 * Are there platforms on which we shouldn't do this?
    184 		 */
    185 		if (strncmp(ifrp->lifr_name, "dummy", 5) == 0)
    186 			continue;
    187 
    188 #ifdef HAVE_SOLARIS
    189 		/*
    190 		 * Skip entries that have a ":" followed by a number
    191 		 * at the end - those are Solaris virtual interfaces
    192 		 * on which you can't capture.
    193 		 */
    194 		p = strchr(ifrp->lifr_name, ':');
    195 		if (p != NULL) {
    196 			/*
    197 			 * We have a ":"; is it followed by a number?
    198 			 */
    199 			while (isdigit((unsigned char)*p))
    200 				p++;
    201 			if (*p == '\0') {
    202 				/*
    203 				 * All digits after the ":" until the end.
    204 				 */
    205 				continue;
    206 			}
    207 		}
    208 #endif
    209 
    210 		/*
    211 		 * Get the flags for this interface, and skip it if it's
    212 		 * not up.
    213 		 */
    214 		strncpy(ifrflags.lifr_name, ifrp->lifr_name,
    215 		    sizeof(ifrflags.lifr_name));
    216 		if (ioctl(fd, SIOCGLIFFLAGS, (char *)&ifrflags) < 0) {
    217 			if (errno == ENXIO)
    218 				continue;
    219 			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    220 			    "SIOCGLIFFLAGS: %.*s: %s",
    221 			    (int)sizeof(ifrflags.lifr_name),
    222 			    ifrflags.lifr_name,
    223 			    pcap_strerror(errno));
    224 			ret = -1;
    225 			break;
    226 		}
    227 		if (!(ifrflags.lifr_flags & IFF_UP))
    228 			continue;
    229 
    230 		/*
    231 		 * Get the netmask for this address on this interface.
    232 		 */
    233 		strncpy(ifrnetmask.lifr_name, ifrp->lifr_name,
    234 		    sizeof(ifrnetmask.lifr_name));
    235 		memcpy(&ifrnetmask.lifr_addr, &ifrp->lifr_addr,
    236 		    sizeof(ifrnetmask.lifr_addr));
    237 		if (ioctl(fd, SIOCGLIFNETMASK, (char *)&ifrnetmask) < 0) {
    238 			if (errno == EADDRNOTAVAIL) {
    239 				/*
    240 				 * Not available.
    241 				 */
    242 				netmask = NULL;
    243 			} else {
    244 				(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    245 				    "SIOCGLIFNETMASK: %.*s: %s",
    246 				    (int)sizeof(ifrnetmask.lifr_name),
    247 				    ifrnetmask.lifr_name,
    248 				    pcap_strerror(errno));
    249 				ret = -1;
    250 				break;
    251 			}
    252 		} else
    253 			netmask = (struct sockaddr *)&ifrnetmask.lifr_addr;
    254 
    255 		/*
    256 		 * Get the broadcast address for this address on this
    257 		 * interface (if any).
    258 		 */
    259 		if (ifrflags.lifr_flags & IFF_BROADCAST) {
    260 			strncpy(ifrbroadaddr.lifr_name, ifrp->lifr_name,
    261 			    sizeof(ifrbroadaddr.lifr_name));
    262 			memcpy(&ifrbroadaddr.lifr_addr, &ifrp->lifr_addr,
    263 			    sizeof(ifrbroadaddr.lifr_addr));
    264 			if (ioctl(fd, SIOCGLIFBRDADDR,
    265 			    (char *)&ifrbroadaddr) < 0) {
    266 				if (errno == EADDRNOTAVAIL) {
    267 					/*
    268 					 * Not available.
    269 					 */
    270 					broadaddr = NULL;
    271 				} else {
    272 					(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    273 					    "SIOCGLIFBRDADDR: %.*s: %s",
    274 					    (int)sizeof(ifrbroadaddr.lifr_name),
    275 					    ifrbroadaddr.lifr_name,
    276 					    pcap_strerror(errno));
    277 					ret = -1;
    278 					break;
    279 				}
    280 			} else
    281 				broadaddr = (struct sockaddr *)&ifrbroadaddr.lifr_broadaddr;
    282 		} else {
    283 			/*
    284 			 * Not a broadcast interface, so no broadcast
    285 			 * address.
    286 			 */
    287 			broadaddr = NULL;
    288 		}
    289 
    290 		/*
    291 		 * Get the destination address for this address on this
    292 		 * interface (if any).
    293 		 */
    294 		if (ifrflags.lifr_flags & IFF_POINTOPOINT) {
    295 			strncpy(ifrdstaddr.lifr_name, ifrp->lifr_name,
    296 			    sizeof(ifrdstaddr.lifr_name));
    297 			memcpy(&ifrdstaddr.lifr_addr, &ifrp->lifr_addr,
    298 			    sizeof(ifrdstaddr.lifr_addr));
    299 			if (ioctl(fd, SIOCGLIFDSTADDR,
    300 			    (char *)&ifrdstaddr) < 0) {
    301 				if (errno == EADDRNOTAVAIL) {
    302 					/*
    303 					 * Not available.
    304 					 */
    305 					dstaddr = NULL;
    306 				} else {
    307 					(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
    308 					    "SIOCGLIFDSTADDR: %.*s: %s",
    309 					    (int)sizeof(ifrdstaddr.lifr_name),
    310 					    ifrdstaddr.lifr_name,
    311 					    pcap_strerror(errno));
    312 					ret = -1;
    313 					break;
    314 				}
    315 			} else
    316 				dstaddr = (struct sockaddr *)&ifrdstaddr.lifr_dstaddr;
    317 		} else
    318 			dstaddr = NULL;
    319 
    320 #ifdef HAVE_SOLARIS
    321 		/*
    322 		 * If this entry has a colon followed by a number at
    323 		 * the end, it's a logical interface.  Those are just
    324 		 * the way you assign multiple IP addresses to a real
    325 		 * interface, so an entry for a logical interface should
    326 		 * be treated like the entry for the real interface;
    327 		 * we do that by stripping off the ":" and the number.
    328 		 */
    329 		p = strchr(ifrp->lifr_name, ':');
    330 		if (p != NULL) {
    331 			/*
    332 			 * We have a ":"; is it followed by a number?
    333 			 */
    334 			q = p + 1;
    335 			while (isdigit((unsigned char)*q))
    336 				q++;
    337 			if (*q == '\0') {
    338 				/*
    339 				 * All digits after the ":" until the end.
    340 				 * Strip off the ":" and everything after
    341 				 * it.
    342 				 */
    343 				*p = '\0';
    344 			}
    345 		}
    346 #endif
    347 
    348 		/*
    349 		 * Add information for this address to the list.
    350 		 */
    351 		if (add_addr_to_iflist(&devlist, ifrp->lifr_name,
    352 		    ifrflags.lifr_flags, (struct sockaddr *)&ifrp->lifr_addr,
    353 		    sizeof (struct sockaddr_storage),
    354 		    netmask, sizeof (struct sockaddr_storage),
    355 		    broadaddr, sizeof (struct sockaddr_storage),
    356 		    dstaddr, sizeof (struct sockaddr_storage), errbuf) < 0) {
    357 			ret = -1;
    358 			break;
    359 		}
    360 	}
    361 	free(buf);
    362 	(void)close(fd6);
    363 	(void)close(fd4);
    364 
    365 	if (ret != -1) {
    366 		/*
    367 		 * We haven't had any errors yet; do any platform-specific
    368 		 * operations to add devices.
    369 		 */
    370 		if (pcap_platform_finddevs(&devlist, errbuf) < 0)
    371 			ret = -1;
    372 	}
    373 
    374 	if (ret == -1) {
    375 		/*
    376 		 * We had an error; free the list we've been constructing.
    377 		 */
    378 		if (devlist != NULL) {
    379 			pcap_freealldevs(devlist);
    380 			devlist = NULL;
    381 		}
    382 	}
    383 
    384 	*alldevsp = devlist;
    385 	return (ret);
    386 }
    387