| /* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */ |
| /* |
| * 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[] _U_ = |
| "@(#) $Header: /tcpdump/master/libpcap/fad-getad.c,v 1.12 2007-09-14 00:44:55 guy Exp $ (LBL)"; |
| #endif |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <sys/types.h> |
| #include <sys/socket.h> |
| #include <netinet/in.h> |
| |
| #include <net/if.h> |
| |
| #include <ctype.h> |
| #include <errno.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <ifaddrs.h> |
| |
| #include "pcap-int.h" |
| |
| #ifdef HAVE_OS_PROTO_H |
| #include "os-proto.h" |
| #endif |
| |
| #ifdef AF_PACKET |
| # ifdef HAVE_NETPACKET_PACKET_H |
| /* Solaris 11 and later, Linux distributions with newer glibc */ |
| # include <netpacket/packet.h> |
| # else /* HAVE_NETPACKET_PACKET_H */ |
| /* LynxOS, Linux distributions with older glibc */ |
| # ifdef __Lynx__ |
| /* LynxOS */ |
| # include <netpacket/if_packet.h> |
| # else /* __Lynx__ */ |
| /* Linux */ |
| # include <linux/types.h> |
| # include <linux/if_packet.h> |
| # endif /* __Lynx__ */ |
| # endif /* HAVE_NETPACKET_PACKET_H */ |
| #endif /* AF_PACKET */ |
| |
| /* |
| * This is fun. |
| * |
| * In older BSD systems, socket addresses were fixed-length, and |
| * "sizeof (struct sockaddr)" gave the size of the structure. |
| * All addresses fit within a "struct sockaddr". |
| * |
| * In newer BSD systems, the socket address is variable-length, and |
| * there's an "sa_len" field giving the length of the structure; |
| * this allows socket addresses to be longer than 2 bytes of family |
| * and 14 bytes of data. |
| * |
| * Some commercial UNIXes use the old BSD scheme, some use the RFC 2553 |
| * variant of the old BSD scheme (with "struct sockaddr_storage" rather |
| * than "struct sockaddr"), and some use the new BSD scheme. |
| * |
| * Some versions of GNU libc use neither scheme, but has an "SA_LEN()" |
| * macro that determines the size based on the address family. Other |
| * versions don't have "SA_LEN()" (as it was in drafts of RFC 2553 |
| * but not in the final version). On the latter systems, we explicitly |
| * check the AF_ type to determine the length; we assume that on |
| * all those systems we have "struct sockaddr_storage". |
| */ |
| #ifndef SA_LEN |
| #ifdef HAVE_SOCKADDR_SA_LEN |
| #define SA_LEN(addr) ((addr)->sa_len) |
| #else /* HAVE_SOCKADDR_SA_LEN */ |
| #ifdef HAVE_SOCKADDR_STORAGE |
| static size_t |
| get_sa_len(struct sockaddr *addr) |
| { |
| switch (addr->sa_family) { |
| |
| #ifdef AF_INET |
| case AF_INET: |
| return (sizeof (struct sockaddr_in)); |
| #endif |
| |
| #ifdef AF_INET6 |
| case AF_INET6: |
| return (sizeof (struct sockaddr_in6)); |
| #endif |
| |
| #ifdef AF_PACKET |
| case AF_PACKET: |
| return (sizeof (struct sockaddr_ll)); |
| #endif |
| |
| default: |
| return (sizeof (struct sockaddr)); |
| } |
| } |
| #define SA_LEN(addr) (get_sa_len(addr)) |
| #else /* HAVE_SOCKADDR_STORAGE */ |
| #define SA_LEN(addr) (sizeof (struct sockaddr)) |
| #endif /* HAVE_SOCKADDR_STORAGE */ |
| #endif /* HAVE_SOCKADDR_SA_LEN */ |
| #endif /* SA_LEN */ |
| |
| /* |
| * Get a list of all interfaces that are up and that we can open. |
| * Returns -1 on error, 0 otherwise. |
| * The list, as returned through "alldevsp", may be null if no interfaces |
| * were up and could be opened. |
| * |
| * This is the implementation used on platforms that have "getifaddrs()". |
| */ |
| int |
| pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf) |
| { |
| pcap_if_t *devlist = NULL; |
| struct ifaddrs *ifap, *ifa; |
| struct sockaddr *addr, *netmask, *broadaddr, *dstaddr; |
| size_t addr_size, broadaddr_size, dstaddr_size; |
| int ret = 0; |
| char *p, *q; |
| |
| /* |
| * Get the list of interface addresses. |
| * |
| * Note: this won't return information about interfaces |
| * with no addresses; are there any such interfaces |
| * that would be capable of receiving packets? |
| * (Interfaces incapable of receiving packets aren't |
| * very interesting from libpcap's point of view.) |
| * |
| * LAN interfaces will probably have link-layer |
| * addresses; I don't know whether all implementations |
| * of "getifaddrs()" now, or in the future, will return |
| * those. |
| */ |
| if (getifaddrs(&ifap) != 0) { |
| (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, |
| "getifaddrs: %s", pcap_strerror(errno)); |
| return (-1); |
| } |
| for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) { |
| /* |
| * Is this interface up? |
| */ |
| if (!(ifa->ifa_flags & IFF_UP)) { |
| /* |
| * No, so don't add it to the list. |
| */ |
| continue; |
| } |
| |
| /* |
| * "ifa_addr" was apparently null on at least one |
| * interface on some system. |
| * |
| * "ifa_broadaddr" may be non-null even on |
| * non-broadcast interfaces, and was null on |
| * at least one OpenBSD 3.4 system on at least |
| * one interface with IFF_BROADCAST set. |
| * |
| * "ifa_dstaddr" was, on at least one FreeBSD 4.1 |
| * system, non-null on a non-point-to-point |
| * interface. |
| * |
| * Therefore, we supply the address and netmask only |
| * if "ifa_addr" is non-null (if there's no address, |
| * there's obviously no netmask), and supply the |
| * broadcast and destination addresses if the appropriate |
| * flag is set *and* the appropriate "ifa_" entry doesn't |
| * evaluate to a null pointer. |
| */ |
| if (ifa->ifa_addr != NULL) { |
| addr = ifa->ifa_addr; |
| addr_size = SA_LEN(addr); |
| netmask = ifa->ifa_netmask; |
| } else { |
| addr = NULL; |
| addr_size = 0; |
| netmask = NULL; |
| } |
| if (ifa->ifa_flags & IFF_BROADCAST && |
| ifa->ifa_broadaddr != NULL) { |
| broadaddr = ifa->ifa_broadaddr; |
| broadaddr_size = SA_LEN(broadaddr); |
| } else { |
| broadaddr = NULL; |
| broadaddr_size = 0; |
| } |
| if (ifa->ifa_flags & IFF_POINTOPOINT && |
| ifa->ifa_dstaddr != NULL) { |
| dstaddr = ifa->ifa_dstaddr; |
| dstaddr_size = SA_LEN(ifa->ifa_dstaddr); |
| } else { |
| dstaddr = NULL; |
| dstaddr_size = 0; |
| } |
| |
| /* |
| * If this entry has a colon followed by a number at |
| * the end, we assume it's a logical interface. Those |
| * are just the way you assign multiple IP addresses to |
| * a real interface on Linux, so an entry for a logical |
| * interface should be treated like the entry for the |
| * real interface; we do that by stripping off the ":" |
| * and the number. |
| * |
| * XXX - should we do this only on Linux? |
| */ |
| p = strchr(ifa->ifa_name, ':'); |
| if (p != NULL) { |
| /* |
| * We have a ":"; is it followed by a number? |
| */ |
| q = p + 1; |
| while (isdigit((unsigned char)*q)) |
| q++; |
| if (*q == '\0') { |
| /* |
| * All digits after the ":" until the end. |
| * Strip off the ":" and everything after |
| * it. |
| */ |
| *p = '\0'; |
| } |
| } |
| |
| /* |
| * Add information for this address to the list. |
| */ |
| if (add_addr_to_iflist(&devlist, ifa->ifa_name, |
| ifa->ifa_flags, addr, addr_size, netmask, addr_size, |
| broadaddr, broadaddr_size, dstaddr, dstaddr_size, |
| errbuf) < 0) { |
| ret = -1; |
| break; |
| } |
| } |
| |
| freeifaddrs(ifap); |
| |
| if (ret != -1) { |
| /* |
| * We haven't had any errors yet; do any platform-specific |
| * operations to add devices. |
| */ |
| if (pcap_platform_finddevs(&devlist, errbuf) < 0) |
| ret = -1; |
| } |
| |
| if (ret == -1) { |
| /* |
| * We had an error; free the list we've been constructing. |
| */ |
| if (devlist != NULL) { |
| pcap_freealldevs(devlist); |
| devlist = NULL; |
| } |
| } |
| |
| *alldevsp = devlist; |
| return (ret); |
| } |