GList * get_interface_list(int *err, char **err_str) { return get_interface_list_findalldevs(err, err_str); }
/* * This will use "pcap_findalldevs()" if we have it, otherwise it'll * fall back on "pcap_lookupdev()". */ GList * get_interface_list(int *err, char **err_str) { GList *il = NULL; wchar_t *names; char *win95names; char ascii_name[MAX_WIN_IF_NAME_LEN + 1]; char ascii_desc[MAX_WIN_IF_NAME_LEN + 1]; int i, j; char errbuf[PCAP_ERRBUF_SIZE]; if (!has_wpcap) { /* * We don't have WinPcap, so we can't get a list of * interfaces. */ *err = DONT_HAVE_PCAP; *err_str = cant_load_winpcap_err("you"); return NULL; } #ifdef HAVE_PCAP_FINDALLDEVS if (p_pcap_findalldevs != NULL) return get_interface_list_findalldevs(err, err_str); #endif /* * In WinPcap, pcap_lookupdev is implemented by calling * PacketGetAdapterNames. According to the documentation * I could find: * * http://www.winpcap.org/docs/man/html/Packet32_8c.html#a43 * * this means that: * * On Windows OT (95, 98, Me), pcap_lookupdev returns a sequence * of bytes consisting of: * * a sequence of null-terminated ASCII strings (i.e., each * one is terminated by a single 0 byte), giving the names * of the interfaces; * * an empty ASCII string (i.e., a single 0 byte); * * a sequence of null-terminated ASCII strings, giving the * descriptions of the interfaces; * * an empty ASCII string. * * On Windows NT (NT 4.0, W2K, WXP, W2K3, etc.), pcap_lookupdev * returns a sequence of bytes consisting of: * * a sequence of null-terminated double-byte Unicode strings * (i.e., each one consits of a sequence of double-byte * characters, terminated by a double-byte 0), giving the * names of the interfaces; * * an empty Unicode string (i.e., a double 0 byte); * * a sequence of null-terminated ASCII strings, giving the * descriptions of the interfaces; * * an empty ASCII string. * * The Nth string in the first sequence is the name of the Nth * adapter; the Nth string in the second sequence is the * description of the Nth adapter. */ names = (wchar_t *)pcap_lookupdev(errbuf); i = 0; if (names) { char* desc = 0; int desc_pos = 0; if (names[0]<256) { /* * If names[0] is less than 256 it means the first * byte is 0. This implies that we are using Unicode * characters. */ while (*(names+desc_pos) || *(names+desc_pos-1)) desc_pos++; desc_pos++; /* Step over the extra '\0' */ desc = (char*)(names + desc_pos); /* cast *after* addition */ while (names[i] != 0) { /* * Copy the Unicode description to an ASCII * string. */ j = 0; while (*desc != 0) { if (j < MAX_WIN_IF_NAME_LEN) ascii_desc[j++] = *desc; desc++; } ascii_desc[j] = '\0'; desc++; /* * Copy the Unicode name to an ASCII string. */ j = 0; while (names[i] != 0) { if (j < MAX_WIN_IF_NAME_LEN) ascii_name[j++] = (char) names[i++]; } ascii_name[j] = '\0'; i++; il = g_list_append(il, if_info_new(ascii_name, ascii_desc, FALSE)); } } else { /* * Otherwise we are in Windows 95/98 and using ASCII * (8-bit) characters. */ win95names=(char *)names; while (*(win95names+desc_pos) || *(win95names+desc_pos-1)) desc_pos++; desc_pos++; /* Step over the extra '\0' */ desc = win95names + desc_pos; while (win95names[i] != '\0') { /* * "&win95names[i]" points to the current * interface name, and "desc" points to * that interface's description. */ il = g_list_append(il, if_info_new(&win95names[i], desc, FALSE)); /* * Skip to the next description. */ while (*desc != 0) desc++; desc++; /* * Skip to the next name. */ while (win95names[i] != 0) i++; i++; } } } if (il == NULL) { /* * No interfaces found. */ *err = NO_INTERFACES_FOUND; if (err_str != NULL) *err_str = NULL; } return il; }
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; char errbuf[PCAP_ERRBUF_SIZE]; gboolean loopback; if (sock < 0) { *err = CANT_GET_INTERFACE_LIST; if (err_str != NULL) { *err_str = g_strdup_printf( "Can't get list of interfaces: error opening socket: %s", g_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) { if (err_str != NULL) { *err_str = g_strdup_printf( "Can't get list of interfaces: SIOCGIFCONF ioctl error: %s", g_strerror(errno)); } goto fail; } } else { if ((unsigned int) ifc.ifc_len < sizeof(struct ifreq)) { if (err_str != NULL) { *err_str = g_strdup( "Can't get list of interfaces: 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); g_strlcpy(ifrflags.ifr_name, ifr->ifr_name, sizeof ifrflags.ifr_name); if (ioctl(sock, SIOCGIFFLAGS, (char *)&ifrflags) < 0) { if (errno == ENXIO) goto next; if (err_str != NULL) { *err_str = g_strdup_printf( "Can't get list of interfaces: SIOCGIFFLAGS error getting flags for interface %s: %s", ifr->ifr_name, g_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, errbuf); 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. */ loopback = ((ifrflags.ifr_flags & IFF_LOOPBACK) || strncmp(ifr->ifr_name, "lo", 2) == 0); if_info = if_info_new(ifr->ifr_name, NULL, loopback); if_info_add_address(if_info, &ifr->ifr_addr); if (loopback) il = g_list_append(il, if_info); else { 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, errbuf); if (pch != NULL) { /* * It worked; we can use the "any" device. */ if_info = if_info_new("any", "Pseudo-device that captures on all interfaces", FALSE); 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; if (err_str != NULL) *err_str = NULL; } 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 */ }