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Diffstat (limited to 'contrib/libpcap/fad-gifc.c')
-rw-r--r-- | contrib/libpcap/fad-gifc.c | 502 |
1 files changed, 502 insertions, 0 deletions
diff --git a/contrib/libpcap/fad-gifc.c b/contrib/libpcap/fad-gifc.c new file mode 100644 index 0000000..0214d59 --- /dev/null +++ b/contrib/libpcap/fad-gifc.c @@ -0,0 +1,502 @@ +/* -*- 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-gifc.c,v 1.4.2.1 2003/11/15 23:26:39 guy Exp $ (LBL)"; +#endif + +#ifdef HAVE_CONFIG_H +#include "config.h" +#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 */ + +struct mbuf; /* Squelch compiler warnings on some platforms for */ +struct rtentry; /* declarations in <net/if.h> */ +#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" + +#ifdef HAVE_OS_PROTO_H +#include "os-proto.h" +#endif + +/* + * 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). + * + * We assume that a UNIX that doesn't have "getifaddrs()" and doesn't have + * SIOCGLIFCONF, but has SIOCGIFCONF, uses "struct sockaddr" for the + * address in an entry returned by SIOCGIFCONF. + */ +#ifndef SA_LEN +#ifdef HAVE_SOCKADDR_SA_LEN +#define SA_LEN(addr) ((addr)->sa_len) +#else /* HAVE_SOCKADDR_SA_LEN */ +#define SA_LEN(addr) (sizeof (struct sockaddr)) +#endif /* HAVE_SOCKADDR_SA_LEN */ +#endif /* SA_LEN */ + +#ifdef HAVE_PROC_NET_DEV +/* + * Get from "/proc/net/dev" all interfaces listed there; if they're + * already in the list of interfaces we have, that won't add another + * instance, but if they're not, that'll add them. + * + * We don't bother getting any addresses for them; it appears you can't + * use SIOCGIFADDR on Linux to get IPv6 addresses for interfaces, and, + * although some other types of addresses can be fetched with SIOCGIFADDR, + * we don't bother with them for now. + * + * We also don't fail if we couldn't open "/proc/net/dev"; we just leave + * the list of interfaces as is. + */ +static int +scan_proc_net_dev(pcap_if_t **devlistp, int fd, char *errbuf) +{ + FILE *proc_net_f; + char linebuf[512]; + int linenum; + unsigned char *p; + char name[512]; /* XXX - pick a size */ + char *q, *saveq; + struct ifreq ifrflags; + int ret = 0; + + proc_net_f = fopen("/proc/net/dev", "r"); + if (proc_net_f == NULL) + return (0); + + for (linenum = 1; + fgets(linebuf, sizeof linebuf, proc_net_f) != NULL; linenum++) { + /* + * Skip the first two lines - they're headers. + */ + if (linenum <= 2) + continue; + + p = &linebuf[0]; + + /* + * Skip leading white space. + */ + while (*p != '\0' && isspace(*p)) + p++; + if (*p == '\0' || *p == '\n') + continue; /* blank line */ + + /* + * Get the interface name. + */ + q = &name[0]; + while (*p != '\0' && !isspace(*p)) { + if (*p == ':') { + /* + * This could be the separator between a + * name and an alias number, or it could be + * the separator between a name with no + * alias number and the next field. + * + * If there's a colon after digits, it + * separates the name and the alias number, + * otherwise it separates the name and the + * next field. + */ + saveq = q; + while (isdigit(*p)) + *q++ = *p++; + if (*p != ':') { + /* + * That was the next field, + * not the alias number. + */ + q = saveq; + } + break; + } else + *q++ = *p++; + } + *q = '\0'; + + /* + * Get the flags for this interface, and skip it if + * it's not up. + */ + strncpy(ifrflags.ifr_name, name, sizeof(ifrflags.ifr_name)); + if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifrflags) < 0) { + if (errno == ENXIO) + continue; + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "SIOCGIFFLAGS: %.*s: %s", + (int)sizeof(ifrflags.ifr_name), + ifrflags.ifr_name, + pcap_strerror(errno)); + ret = -1; + break; + } + if (!(ifrflags.ifr_flags & IFF_UP)) + continue; + + /* + * Add an entry for this interface, with no addresses. + */ + if (pcap_add_if(devlistp, name, ifrflags.ifr_flags, NULL, + errbuf) == -1) { + /* + * Failure. + */ + ret = -1; + break; + } + } + if (ret != -1) { + /* + * Well, we didn't fail for any other reason; did we + * fail due to an error reading the file? + */ + if (ferror(proc_net_f)) { + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "Error reading /proc/net/dev: %s", + pcap_strerror(errno)); + ret = -1; + } + } + + (void)fclose(proc_net_f); + return (ret); +} +#endif /* HAVE_PROC_NET_DEV */ + +/* + * 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 SIOCGIFCONF but + * don't have any other mechanism for getting a list of interfaces. + * + * XXX - or platforms that have other, better mechanisms but for which + * we don't yet have code to use that mechanism; I think there's a better + * way on Linux, for example. + */ +int +pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf) +{ + pcap_if_t *devlist = NULL; + register int fd; + register struct ifreq *ifrp, *ifend, *ifnext; + int n; + struct ifconf ifc; + char *buf = NULL; + unsigned buf_size; + struct ifreq ifrflags, ifrnetmask, ifrbroadaddr, ifrdstaddr; + struct sockaddr *netmask, *broadaddr, *dstaddr; + size_t netmask_size, broadaddr_size, dstaddr_size; + int ret = 0; + + /* + * Create a socket from which to fetch the list of interfaces. + */ + fd = socket(AF_INET, SOCK_DGRAM, 0); + if (fd < 0) { + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "socket: %s", pcap_strerror(errno)); + return (-1); + } + + /* + * Start with an 8K buffer, and keep growing the buffer until + * we get the entire interface list or fail to get it for some + * reason other than EINVAL (which is presumed here to mean + * "buffer is too small"). + */ + buf_size = 8192; + for (;;) { + buf = malloc(buf_size); + if (buf == NULL) { + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "malloc: %s", pcap_strerror(errno)); + (void)close(fd); + return (-1); + } + + ifc.ifc_len = buf_size; + ifc.ifc_buf = buf; + memset(buf, 0, buf_size); + if (ioctl(fd, SIOCGIFCONF, (char *)&ifc) < 0 + && errno != EINVAL) { + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "SIOCGIFCONF: %s", pcap_strerror(errno)); + (void)close(fd); + free(buf); + return (-1); + } + if (ifc.ifc_len < buf_size) + break; + free(buf); + buf_size *= 2; + } + + ifrp = (struct ifreq *)buf; + ifend = (struct ifreq *)(buf + ifc.ifc_len); + + for (; ifrp < ifend; ifrp = ifnext) { + /* + * XXX - what if this isn't an IPv4 address? Can + * we still get the netmask, etc. with ioctls on + * an IPv4 socket? + * + * The answer is probably platform-dependent, and + * if the answer is "no" on more than one platform, + * the way you work around it is probably platform- + * dependent as well. + */ + n = SA_LEN(&ifrp->ifr_addr) + sizeof(ifrp->ifr_name); + if (n < sizeof(*ifrp)) + ifnext = ifrp + 1; + else + ifnext = (struct ifreq *)((char *)ifrp + n); + + /* + * Get the flags for this interface, and skip it if it's + * not up. + */ + strncpy(ifrflags.ifr_name, ifrp->ifr_name, + sizeof(ifrflags.ifr_name)); + if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifrflags) < 0) { + if (errno == ENXIO) + continue; + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "SIOCGIFFLAGS: %.*s: %s", + (int)sizeof(ifrflags.ifr_name), + ifrflags.ifr_name, + pcap_strerror(errno)); + ret = -1; + break; + } + if (!(ifrflags.ifr_flags & IFF_UP)) + continue; + + /* + * Get the netmask for this address on this interface. + */ + strncpy(ifrnetmask.ifr_name, ifrp->ifr_name, + sizeof(ifrnetmask.ifr_name)); + memcpy(&ifrnetmask.ifr_addr, &ifrp->ifr_addr, + sizeof(ifrnetmask.ifr_addr)); + if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifrnetmask) < 0) { + if (errno == EADDRNOTAVAIL) { + /* + * Not available. + */ + netmask = NULL; + netmask_size = 0; + } else { + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "SIOCGIFNETMASK: %.*s: %s", + (int)sizeof(ifrnetmask.ifr_name), + ifrnetmask.ifr_name, + pcap_strerror(errno)); + ret = -1; + break; + } + } else { + netmask = &ifrnetmask.ifr_addr; + netmask_size = SA_LEN(netmask); + } + + /* + * Get the broadcast address for this address on this + * interface (if any). + */ + if (ifrflags.ifr_flags & IFF_BROADCAST) { + strncpy(ifrbroadaddr.ifr_name, ifrp->ifr_name, + sizeof(ifrbroadaddr.ifr_name)); + memcpy(&ifrbroadaddr.ifr_addr, &ifrp->ifr_addr, + sizeof(ifrbroadaddr.ifr_addr)); + if (ioctl(fd, SIOCGIFBRDADDR, + (char *)&ifrbroadaddr) < 0) { + if (errno == EADDRNOTAVAIL) { + /* + * Not available. + */ + broadaddr = NULL; + broadaddr_size = 0; + } else { + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "SIOCGIFBRDADDR: %.*s: %s", + (int)sizeof(ifrbroadaddr.ifr_name), + ifrbroadaddr.ifr_name, + pcap_strerror(errno)); + ret = -1; + break; + } + } else { + broadaddr = &ifrbroadaddr.ifr_broadaddr; + broadaddr_size = SA_LEN(broadaddr); + } + } else { + /* + * Not a broadcast interface, so no broadcast + * address. + */ + broadaddr = NULL; + broadaddr_size = 0; + } + + /* + * Get the destination address for this address on this + * interface (if any). + */ + if (ifrflags.ifr_flags & IFF_POINTOPOINT) { + strncpy(ifrdstaddr.ifr_name, ifrp->ifr_name, + sizeof(ifrdstaddr.ifr_name)); + memcpy(&ifrdstaddr.ifr_addr, &ifrp->ifr_addr, + sizeof(ifrdstaddr.ifr_addr)); + if (ioctl(fd, SIOCGIFDSTADDR, + (char *)&ifrdstaddr) < 0) { + if (errno == EADDRNOTAVAIL) { + /* + * Not available. + */ + dstaddr = NULL; + dstaddr_size = 0; + } else { + (void)snprintf(errbuf, PCAP_ERRBUF_SIZE, + "SIOCGIFDSTADDR: %.*s: %s", + (int)sizeof(ifrdstaddr.ifr_name), + ifrdstaddr.ifr_name, + pcap_strerror(errno)); + ret = -1; + break; + } + } else { + dstaddr = &ifrdstaddr.ifr_dstaddr; + dstaddr_size = SA_LEN(dstaddr); + } + } else { + /* + * Not a point-to-point interface, so no destination + * address. + */ + dstaddr = NULL; + dstaddr_size = 0; + } + + /* + * Add information for this address to the list. + */ + if (add_addr_to_iflist(&devlist, ifrp->ifr_name, + ifrflags.ifr_flags, &ifrp->ifr_addr, + SA_LEN(&ifrp->ifr_addr), netmask, netmask_size, + broadaddr, broadaddr_size, dstaddr, dstaddr_size, + errbuf) < 0) { + ret = -1; + break; + } + } + free(buf); + +#ifdef HAVE_PROC_NET_DEV + if (ret != -1) { + /* + * We haven't had any errors yet; now read "/proc/net/dev", + * and add to the list of interfaces all interfaces listed + * there that we don't already have, because, on Linux, + * SIOCGIFCONF reports only interfaces with IPv4 addresses, + * so you need to read "/proc/net/dev" to get the names of + * the rest of the interfaces. + */ + ret = scan_proc_net_dev(&devlist, fd, errbuf); + } +#endif + (void)close(fd); + + 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); +} |