diff options
Diffstat (limited to 'capture-pcap-util-unix.c')
| -rw-r--r-- | capture-pcap-util-unix.c | 338 |
1 files changed, 338 insertions, 0 deletions
diff --git a/capture-pcap-util-unix.c b/capture-pcap-util-unix.c new file mode 100644 index 0000000000..ad563995ea --- /dev/null +++ b/capture-pcap-util-unix.c @@ -0,0 +1,338 @@ +/* capture-pcap-util-unix.c + * UN*X-specific utility routines for packet capture + * + * $Id$ + * + * Ethereal - Network traffic analyzer + * By Gerald Combs <gerald@ethereal.com> + * Copyright 1998 Gerald Combs + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include <glib.h> + +#ifdef HAVE_LIBPCAP + +#include <stdlib.h> +#include <string.h> +#include <stdio.h> +#include <errno.h> + +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif + +#ifdef HAVE_SYS_SOCKET_H +#include <sys/socket.h> +#endif + +#ifdef HAVE_SYS_IOCTL_H +#include <sys/ioctl.h> +#endif + +#include <pcap.h> + +/* + * Keep Digital UNIX happy when including <net/if.h>. + */ +struct mbuf; +struct rtentry; +#include <net/if.h> + +#ifdef HAVE_SYS_SOCKIO_H +# include <sys/sockio.h> +#endif + +#include "capture-pcap-util.h" +#include "capture-pcap-util-int.h" + +#ifndef HAVE_PCAP_FINDALLDEVS +struct search_user_data { + char *name; + if_info_t *if_info; +}; + +static void +search_for_if_cb(gpointer data, gpointer user_data); +#endif + +GList * +get_interface_list(int *err, char *err_str) +{ +#ifdef HAVE_PCAP_FINDALLDEVS + return get_interface_list_findalldevs(err, err_str); +#else + GList *il = NULL; + gint nonloopback_pos = 0; + struct ifreq *ifr, *last; + struct ifconf ifc; + struct ifreq ifrflags; + int sock = socket(AF_INET, SOCK_DGRAM, 0); + struct search_user_data user_data; + pcap_t *pch; + int len, lastlen; + char *buf; + if_info_t *if_info; + + if (sock < 0) { + *err = CANT_GET_INTERFACE_LIST; + g_snprintf(err_str, PCAP_ERRBUF_SIZE, "Error opening socket: %s", + strerror(errno)); + return NULL; + } + + /* + * This code came from: W. Richard Stevens: "UNIX Network Programming", + * Networking APIs: Sockets and XTI, Vol 1, page 434. + */ + lastlen = 0; + len = 100 * sizeof(struct ifreq); + for ( ; ; ) { + buf = g_malloc(len); + ifc.ifc_len = len; + ifc.ifc_buf = buf; + memset (buf, 0, len); + if (ioctl(sock, SIOCGIFCONF, &ifc) < 0) { + if (errno != EINVAL || lastlen != 0) { + g_snprintf(err_str, PCAP_ERRBUF_SIZE, + "SIOCGIFCONF ioctl error getting list of interfaces: %s", + strerror(errno)); + goto fail; + } + } else { + if ((unsigned) ifc.ifc_len < sizeof(struct ifreq)) { + g_snprintf(err_str, PCAP_ERRBUF_SIZE, + "SIOCGIFCONF ioctl gave too small return buffer"); + goto fail; + } + if (ifc.ifc_len == lastlen) + break; /* success, len has not changed */ + lastlen = ifc.ifc_len; + } + len += 10 * sizeof(struct ifreq); /* increment */ + g_free(buf); + } + ifr = (struct ifreq *) ifc.ifc_req; + last = (struct ifreq *) ((char *) ifr + ifc.ifc_len); + while (ifr < last) { + /* + * Skip entries that begin with "dummy", or that include + * a ":" (the latter are Solaris virtuals). + */ + if (strncmp(ifr->ifr_name, "dummy", 5) == 0 || + strchr(ifr->ifr_name, ':') != NULL) + goto next; + + /* + * If we already have this interface name on the list, + * don't add it, but, if we don't already have an IP + * address for it, add that address (SIOCGIFCONF returns, + * at least on BSD-flavored systems, one entry per + * interface *address*; if an interface has multiple + * addresses, we get multiple entries for it). + */ + user_data.name = ifr->ifr_name; + user_data.if_info = NULL; + g_list_foreach(il, search_for_if_cb, &user_data); + if (user_data.if_info != NULL) { + if_info_add_address(user_data.if_info, &ifr->ifr_addr); + goto next; + } + + /* + * Get the interface flags. + */ + memset(&ifrflags, 0, sizeof ifrflags); + strncpy(ifrflags.ifr_name, ifr->ifr_name, + sizeof ifrflags.ifr_name); + if (ioctl(sock, SIOCGIFFLAGS, (char *)&ifrflags) < 0) { + if (errno == ENXIO) + goto next; + g_snprintf(err_str, PCAP_ERRBUF_SIZE, + "SIOCGIFFLAGS error getting flags for interface %s: %s", + ifr->ifr_name, strerror(errno)); + goto fail; + } + + /* + * Skip interfaces that aren't up. + */ + if (!(ifrflags.ifr_flags & IFF_UP)) + goto next; + + /* + * Skip interfaces that we can't open with "libpcap". + * Open with the minimum packet size - it appears that the + * IRIX SIOCSNOOPLEN "ioctl" may fail if the capture length + * supplied is too large, rather than just truncating it. + */ + pch = pcap_open_live(ifr->ifr_name, MIN_PACKET_SIZE, 0, 0, + err_str); + if (pch == NULL) + goto next; + pcap_close(pch); + + /* + * If it's a loopback interface, add it at the end of the + * list, otherwise add it after the last non-loopback + * interface, so all loopback interfaces go at the end - we + * don't want a loopback interface to be the default capture + * device unless there are no non-loopback devices. + */ + if_info = if_info_new(ifr->ifr_name, NULL); + if_info_add_address(if_info, &ifr->ifr_addr); + if ((ifrflags.ifr_flags & IFF_LOOPBACK) || + strncmp(ifr->ifr_name, "lo", 2) == 0) { + if_info->loopback = TRUE; + il = g_list_append(il, if_info); + } else { + if_info->loopback = FALSE; + il = g_list_insert(il, if_info, nonloopback_pos); + /* + * Insert the next non-loopback interface after this + * one. + */ + nonloopback_pos++; + } + + next: +#ifdef HAVE_SA_LEN + ifr = (struct ifreq *) ((char *) ifr + + (ifr->ifr_addr.sa_len > sizeof(ifr->ifr_addr) ? + ifr->ifr_addr.sa_len : sizeof(ifr->ifr_addr)) + + IFNAMSIZ); +#else + ifr = (struct ifreq *) ((char *) ifr + sizeof(struct ifreq)); +#endif + } + +#ifdef linux + /* + * OK, maybe we have support for the "any" device, to do a cooked + * capture on all interfaces at once. + * Try opening it and, if that succeeds, add it to the end of + * the list of interfaces. + */ + pch = pcap_open_live("any", MIN_PACKET_SIZE, 0, 0, err_str); + if (pch != NULL) { + /* + * It worked; we can use the "any" device. + */ + if_info = if_info_new("any", + "Pseudo-device that captures on all interfaces"); + il = g_list_insert(il, if_info, -1); + pcap_close(pch); + } +#endif + + g_free(ifc.ifc_buf); + close(sock); + + if (il == NULL) { + /* + * No interfaces found. + */ + *err = NO_INTERFACES_FOUND; + } + return il; + +fail: + if (il != NULL) + free_interface_list(il); + g_free(ifc.ifc_buf); + close(sock); + *err = CANT_GET_INTERFACE_LIST; + return NULL; +#endif /* HAVE_PCAP_FINDALLDEVS */ +} + +#ifndef HAVE_PCAP_FINDALLDEVS +static void +search_for_if_cb(gpointer data, gpointer user_data) +{ + struct search_user_data *search_user_data = user_data; + if_info_t *if_info = data; + + if (strcmp(if_info->name, search_user_data->name) == 0) + search_user_data->if_info = if_info; +} +#endif /* HAVE_PCAP_FINDALLDEVS */ + +/* + * Get an error message string for a CANT_GET_INTERFACE_LIST error from + * "get_interface_list()". + */ +gchar * +cant_get_if_list_error_message(const char *err_str) +{ + return g_strdup_printf("Can't get list of interfaces: %s", err_str); +} + +/* + * Append the version of libpcap with which we were compiled to a GString. + */ +void +get_compiled_pcap_version(GString *str) +{ +#ifdef HAVE_PCAP_VERSION + extern char pcap_version[]; + + g_string_sprintfa(str, "with libpcap %s", pcap_version); +#else + g_string_append(str, "with libpcap (version unknown)"); +#endif +} + +/* + * Append the version of libpcap with which we we're running to a GString. + */ +void +get_runtime_pcap_version(GString *str) +{ + g_string_sprintfa(str, "with "); +#ifdef HAVE_PCAP_LIB_VERSION + g_string_sprintfa(str, pcap_lib_version()); +#else + g_string_append(str, "libpcap (version unknown)"); +#endif + g_string_append(str, " "); +} + +#else /* HAVE_LIBPCAP */ + +/* + * Append an indication that we were not compiled with libpcap + * to a GString. + */ +void +get_compiled_pcap_version(GString *str) +{ + g_string_append(str, "without libpcap"); +} + +/* + * Don't append anything, as we weren't even compiled to use WinPcap. + */ +void +get_runtime_pcap_version(GString *str _U_) +{ +} + +#endif /* HAVE_LIBPCAP */ |