/* * * Wireless daemon for Linux * * Copyright (C) 2013-2019 Intel Corporation. All rights reserved. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ #ifdef HAVE_CONFIG_H #include #endif #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef ARPHRD_NETLINK #define ARPHRD_NETLINK 824 #endif #include "linux/nl80211.h" #include "monitor/nlmon.h" #include "monitor/pcap.h" #include "monitor/display.h" #define MAX_SNAPLEN (1024 * 16) static struct nlmon *nlmon = NULL; static const char *writer_path = NULL; static struct l_timeout *timeout = NULL; static struct nlmon_config config; #define NLA_OK(nla,len) ((len) >= (int) sizeof(struct nlattr) && \ (nla)->nla_len >= sizeof(struct nlattr) && \ (nla)->nla_len <= (len)) #define NLA_NEXT(nla,attrlen) ((attrlen) -= NLA_ALIGN((nla)->nla_len), \ (struct nlattr*)(((char*)(nla)) + \ NLA_ALIGN((nla)->nla_len))) #define NLA_LENGTH(len) (NLA_ALIGN(sizeof(struct nlattr)) + (len)) #define NLA_DATA(nla) ((void*)(((char*)(nla)) + NLA_LENGTH(0))) #define NLA_PAYLOAD(nla) ((int)((nla)->nla_len - NLA_LENGTH(0))) #define NLMON_TYPE "nlmon" #define NLMON_LEN 5 static bool nlmon_receive(struct l_io *io, void *user_data) { struct nlmon *nlmon = user_data; struct msghdr msg; struct sockaddr_ll sll; struct iovec iov; struct cmsghdr *cmsg; struct timeval copy_tv; const struct timeval *tv = NULL; uint16_t proto_type; unsigned char buf[8192]; unsigned char control[32]; ssize_t bytes_read; int fd; fd = l_io_get_fd(io); if (fd < 0) return false; memset(&sll, 0, sizeof(sll)); memset(&iov, 0, sizeof(iov)); iov.iov_base = buf; iov.iov_len = sizeof(buf); memset(&msg, 0, sizeof(msg)); msg.msg_name = &sll; msg.msg_namelen = sizeof(sll); msg.msg_iov = &iov; msg.msg_iovlen = 1; msg.msg_control = control; msg.msg_controllen = sizeof(control); bytes_read = recvmsg(fd, &msg, 0); if (bytes_read < 0) { if (errno != EAGAIN && errno != EINTR) return false; return true; } if (sll.sll_hatype != ARPHRD_NETLINK) return true; proto_type = ntohs(sll.sll_protocol); for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) { if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_TIMESTAMP) { memcpy(©_tv, CMSG_DATA(cmsg), sizeof(copy_tv)); tv = ©_tv; } } switch (proto_type) { case NETLINK_ROUTE: nlmon_print_rtnl(nlmon, tv, iov.iov_base, bytes_read); break; case NETLINK_GENERIC: nlmon_print_genl(nlmon, tv, iov.iov_base, bytes_read); break; } return true; } /* * BPF filter to match skb->dev->type == 824 (ARPHRD_NETLINK) and * either match skb->protocol == 0x0000 (NETLINK_ROUTE) or match * skb->protocol == 0x0010 (NETLINK_GENERIC). */ static struct sock_filter mon_filter[] = { { 0x28, 0, 0, 0xfffff01c }, /* ldh #hatype */ { 0x15, 0, 3, 0x00000338 }, /* jne #824, drop */ { 0x28, 0, 0, 0xfffff000 }, /* ldh #proto */ { 0x15, 2, 0, 0000000000 }, /* jeq #0x0000, pass */ { 0x15, 1, 0, 0x00000010 }, /* jeq #0x0010, pass */ { 0x06, 0, 0, 0000000000 }, /* drop: ret #0 */ { 0x06, 0, 0, 0xffffffff }, /* pass: ret #-1 */ }; static const struct sock_fprog mon_fprog = { .len = 7, .filter = mon_filter }; static struct l_io *open_packet(const char *name) { struct l_io *io; struct sockaddr_ll sll; struct packet_mreq mr; struct ifreq ifr; int fd, opt = 1; fd = socket(PF_PACKET, SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK, 0); if (fd < 0) { perror("Failed to create packet socket"); return NULL; } strncpy(ifr.ifr_name, name, IFNAMSIZ - 1); if (ioctl(fd, SIOCGIFINDEX, &ifr) < 0) { perror("Failed to get monitor index"); close(fd); return NULL; } memset(&sll, 0, sizeof(sll)); sll.sll_family = AF_PACKET; sll.sll_protocol = htons(ETH_P_ALL); sll.sll_ifindex = ifr.ifr_ifindex; if (bind(fd, (struct sockaddr *) &sll, sizeof(sll)) < 0) { perror("Failed to bind packet socket"); close(fd); return NULL; } memset(&mr, 0, sizeof(mr)); mr.mr_ifindex = ifr.ifr_ifindex; mr.mr_type = PACKET_MR_ALLMULTI; if (setsockopt(fd, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mr, sizeof(mr)) < 0) { perror("Failed to enable all multicast"); close(fd); return NULL; } if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &mon_fprog, sizeof(mon_fprog)) < 0) { perror("Failed to enable monitor filter"); close(fd); return NULL; } if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMP, &opt, sizeof(opt)) < 0) { perror("Failed to enable monitor timestamps"); close(fd); return NULL; } io = l_io_new(fd); l_io_set_close_on_destroy(io, true); return io; } struct iwmon_interface { char *ifname; bool exists; struct l_netlink *rtnl; struct l_genl *genl; struct l_io *io; }; static struct iwmon_interface monitor_interface = { }; static void nl80211_appeared(const struct l_genl_family_info *info, void *user_data) { const char *ifname = user_data; monitor_interface.io = open_packet(ifname); if (!monitor_interface.io) goto failed; nlmon = nlmon_open(l_genl_family_info_get_id(info), writer_path, &config); if (!nlmon) goto failed; l_io_set_read_handler(monitor_interface.io, nlmon_receive, nlmon, NULL); return; failed: l_main_quit(); } static struct l_genl *genl_lookup(const char *ifname) { struct l_genl *genl = l_genl_new(); l_genl_request_family(genl, NL80211_GENL_NAME, nl80211_appeared, (char *) ifname, NULL); return genl; } static bool rta_linkinfo_kind(struct rtattr *rta, unsigned short len, const char* kind) { for (; RTA_OK(rta, len); rta = RTA_NEXT(rta, len)) { if (rta->rta_type != IFLA_INFO_KIND) continue; if (rta->rta_len < NLMON_LEN) continue; if (memcmp(RTA_DATA(rta), kind, strlen(kind))) continue; return true; } return false; } static struct l_netlink *rtm_interface_send_message(struct l_netlink *rtnl, const char *ifname, uint16_t rtm_msg_type, l_netlink_command_func_t callback, void *user_data, l_netlink_destroy_func_t destroy) { size_t nlmon_type_len = strlen(NLMON_TYPE); unsigned short ifname_len = 0; struct l_netlink_message *nlm; struct ifinfomsg ifi; uint16_t flags = 0; if (ifname) { ifname_len = strlen(ifname) + 1; if (ifname_len < 2 || ifname_len > IFNAMSIZ) return NULL; } if (!L_IN_SET(rtm_msg_type, RTM_NEWLINK, RTM_DELLINK, RTM_GETLINK)) return NULL; if (!rtnl) rtnl = l_netlink_new(NETLINK_ROUTE); if (!rtnl) return NULL; memset(&ifi, 0, sizeof(ifi)); ifi.ifi_family = AF_UNSPEC; ifi.ifi_change = ~0; switch (rtm_msg_type) { case RTM_NEWLINK: ifi.ifi_flags = IFF_UP | IFF_ALLMULTI | IFF_NOARP; flags = NLM_F_CREATE | NLM_F_EXCL; break; case RTM_GETLINK: flags = NLM_F_DUMP; break; } nlm = l_netlink_message_new(rtm_msg_type, flags);; l_netlink_message_add_header(nlm, &ifi, sizeof(ifi)); if (ifname) l_netlink_message_append(nlm, IFLA_IFNAME, ifname, ifname_len); l_netlink_message_enter_nested(nlm, IFLA_LINKINFO); l_netlink_message_append(nlm, IFLA_INFO_KIND, NLMON_TYPE, nlmon_type_len); l_netlink_message_leave_nested(nlm); l_netlink_send(rtnl, nlm, callback, user_data, destroy); return rtnl; } static struct l_netlink *iwmon_interface_disable( struct iwmon_interface *monitor_interface) { if (!monitor_interface->exists) return rtm_interface_send_message(monitor_interface->rtnl, monitor_interface->ifname, RTM_DELLINK, NULL, NULL, NULL); return monitor_interface->rtnl; } static void iwmon_interface_enable_callback(int error, uint16_t type, const void *data, uint32_t len, void *user_data) { struct iwmon_interface *monitor_interface = user_data; if (error) { fprintf(stderr, "Failed to create monitor interface %s: %s\n", monitor_interface->ifname, strerror(error)); l_main_quit(); return; } printf("Created interface %s\n", monitor_interface->ifname); monitor_interface->genl = genl_lookup(monitor_interface->ifname); } static struct l_netlink *iwmon_interface_enable( struct iwmon_interface *monitor_interface) { return rtm_interface_send_message(monitor_interface->rtnl, monitor_interface->ifname, RTM_NEWLINK, iwmon_interface_enable_callback, monitor_interface, NULL); } static void iwmon_interface_lookup_done(void *user_data) { struct iwmon_interface *monitor_interface = user_data; if (monitor_interface->exists && monitor_interface->ifname) { printf("Using %s as Monitor interface\n", monitor_interface->ifname); monitor_interface->genl = genl_lookup(monitor_interface->ifname); return; } if (!monitor_interface->ifname) monitor_interface->ifname = l_strdup(NLMON_TYPE); iwmon_interface_enable(monitor_interface); } static void iwmon_interface_lookup_callback(int error, uint16_t type, const void *data, uint32_t len, void *user_data) { const struct ifinfomsg *rtmmsg = data; struct rtattr *rta; struct iwmon_interface *monitor_interface = user_data; const char *ifname = NULL; unsigned short ifname_len = 0; bool nlmon = false; if (error) return; if (type != RTM_NEWLINK) return; for (rta = (struct rtattr *)(rtmmsg + 1); RTA_OK(rta, len); rta = RTA_NEXT(rta, len)) { switch(rta->rta_type) { case IFLA_IFNAME: ifname = RTA_DATA(rta); ifname_len = rta->rta_len; break; case IFLA_LINKINFO: nlmon = rta_linkinfo_kind(RTA_DATA(rta), rta->rta_len, NLMON_TYPE); break; default: break; } } if (!ifname) return; if (!nlmon) return; if ((rtmmsg->ifi_flags & (IFF_UP | IFF_ALLMULTI | IFF_NOARP)) != (IFF_UP | IFF_ALLMULTI | IFF_NOARP)) return; l_free(monitor_interface->ifname); monitor_interface->ifname = l_strndup(ifname, ifname_len); monitor_interface->exists = true; } static void iwmon_interface_lookup(struct iwmon_interface *monitor_interface) { monitor_interface->rtnl = rtm_interface_send_message(monitor_interface->rtnl, NULL, RTM_GETLINK, iwmon_interface_lookup_callback, monitor_interface, iwmon_interface_lookup_done); } static int analyze_pcap(const char *pathname) { struct l_queue *genl_list; const struct l_queue_entry *genl_entry; struct pcap *pcap; struct timeval tv; void *buf; uint32_t snaplen, len, real_len; int exit_status; unsigned long pkt_count = 0; unsigned long pkt_short = 0; unsigned long pkt_trunc = 0; unsigned long pkt_ether = 0; unsigned long pkt_pae = 0; unsigned long pkt_netlink = 0; unsigned long pkt_rtnl = 0; unsigned long pkt_genl = 0; unsigned long msg_netlink = 0; unsigned long msg_rtnl = 0; unsigned long msg_genl = 0; bool first; pcap = pcap_open(pathname); if (!pcap) return EXIT_FAILURE; if (pcap_get_type(pcap) != PCAP_TYPE_LINUX_SLL) { fprintf(stderr, "Invalid packet format\n"); exit_status = EXIT_FAILURE; goto done; } snaplen = pcap_get_snaplen(pcap); if (snaplen > MAX_SNAPLEN) snaplen = MAX_SNAPLEN; buf = malloc(snaplen); if (!buf) { fprintf(stderr, "Failed to allocate packet buffer\n"); exit_status = EXIT_FAILURE; goto done; } genl_list = l_queue_new(); while (pcap_read(pcap, &tv, buf, snaplen, &len, &real_len)) { struct nlmsghdr *nlmsg; int64_t aligned_len; uint16_t arphrd_type; uint16_t proto_type; pkt_count++; if (len < 16) { pkt_short++; continue; } arphrd_type = l_get_be16(buf + 2); proto_type = l_get_be16(buf + 14); switch (arphrd_type) { case ARPHRD_ETHER: pkt_ether++; switch (proto_type) { case ETH_P_PAE: pkt_pae++; break; } break; case ARPHRD_NETLINK: pkt_netlink++; switch (proto_type) { case NETLINK_ROUTE: pkt_rtnl++; break; case NETLINK_GENERIC: pkt_genl++; break; } break; } if (len < real_len) { pkt_trunc++; continue; } if (arphrd_type != ARPHRD_NETLINK) continue; aligned_len = NLMSG_ALIGN(len - 16); for (nlmsg = buf + 16; NLMSG_OK(nlmsg, aligned_len); nlmsg = NLMSG_NEXT(nlmsg, aligned_len)) { uint16_t type = nlmsg->nlmsg_type; msg_netlink++; switch (proto_type) { case NETLINK_ROUTE: msg_rtnl++; break; case NETLINK_GENERIC: if (type >= NLMSG_MIN_TYPE) { l_queue_remove(genl_list, L_UINT_TO_PTR(type)); l_queue_push_tail(genl_list, L_UINT_TO_PTR(type)); } msg_genl++; break; } } } printf("\n"); printf(" Analyzed file: %s\n", pathname); printf("\n"); printf(" Number of packets: %lu\n", pkt_count); printf(" Short packets: %lu\n", pkt_short); printf(" Truncated packets: %lu\n", pkt_trunc); printf("\n"); printf(" Ethernet packets: %lu\n", pkt_ether); printf(" PAE packets: %lu\n", pkt_pae); printf("\n"); printf(" Netlink packets: %lu\n", pkt_netlink); printf(" RTNL packets: %lu\n", pkt_rtnl); printf(" GENL packets: %lu\n", pkt_genl); printf("\n"); printf(" Netlink messages: %lu\n", msg_netlink); printf(" RTNL messages: %lu\n", msg_rtnl); printf(" GENL messages: %lu\n", msg_genl); printf("\n"); for (genl_entry = l_queue_get_entries(genl_list), first = true; genl_entry; genl_entry = genl_entry->next, first = false) { uint16_t family = L_PTR_TO_UINT(genl_entry->data); const char *label, *desc; if (first) label = " GENL families:"; else label = " "; if (family == GENL_ID_CTRL) desc = "nlctrl"; else desc = ""; printf("%s 0x%02x (%u) %s\n", label, family, family, desc); } printf("\n"); l_queue_destroy(genl_list, NULL); free(buf); exit_status = EXIT_SUCCESS; done: pcap_close(pcap); return exit_status; } static int process_pcap(struct pcap *pcap, const struct nlmon_config *config) { struct nlmon *nlmon = NULL; struct timeval tv; uint8_t *buf; uint32_t snaplen, len, real_len; snaplen = pcap_get_snaplen(pcap); if (snaplen > MAX_SNAPLEN) snaplen = MAX_SNAPLEN; buf = malloc(snaplen); if (!buf) { fprintf(stderr, "Failed to allocate packet buffer\n"); return EXIT_FAILURE; } nlmon = nlmon_create(0, config); while (pcap_read(pcap, &tv, buf, snaplen, &len, &real_len)) { uint16_t arphrd_type; uint16_t proto_type; uint16_t pkt_type; if (len < 16) { printf("Too short packet\n"); continue; } if (len < real_len) { printf("Packet truncated from %u\n", real_len); continue; } pkt_type = l_get_be16(buf); arphrd_type = l_get_be16(buf + 2); proto_type = l_get_be16(buf + 14); switch (arphrd_type) { case ARPHRD_ETHER: switch (proto_type) { case ETH_P_PAE: nlmon_print_pae(nlmon, &tv, pkt_type, -1, buf + 16, len - 16); break; } break; case ARPHRD_NETLINK: switch (proto_type) { case NETLINK_ROUTE: nlmon_print_rtnl(nlmon, &tv, buf + 16, len - 16); break; case NETLINK_GENERIC: nlmon_print_genl(nlmon, &tv, buf + 16, len - 16); break; } break; default: printf("Unsupported ARPHRD %u\n", arphrd_type); break; } } nlmon_destroy(nlmon); free(buf); return EXIT_SUCCESS; } static void main_loop_quit(struct l_timeout *timeout, void *user_data) { l_main_quit(); } static void signal_handler(uint32_t signo, void *user_data) { switch (signo) { case SIGINT: case SIGTERM: iwmon_interface_disable(&monitor_interface); timeout = l_timeout_create(1, main_loop_quit, NULL, NULL); break; } } static void usage(void) { printf("iwmon - Wireless monitor\n" "Usage:\n"); printf("\tiwmon [options]\n"); printf("Options:\n" "\t-r, --read Read netlink PCAP trace file\n" "\t-w, --write Write netlink PCAP trace file\n" "\t-a, --analyze Analyze netlink PCAP trace file\n" "\t-i, --interface Use specified netlink monitor\n" "\t-n, --nortnl Don't show RTNL output\n" "\t-y, --nowiphy Don't show 'New Wiphy' output\n" "\t-s, --noscan Don't show scan result output\n" "\t-e, --noies Don't show IEs except SSID\n" "\t-h, --help Show help options\n"); } static const struct option main_options[] = { { "read", required_argument, NULL, 'r' }, { "write", required_argument, NULL, 'w' }, { "analyze", required_argument, NULL, 'a' }, { "nl80211", required_argument, NULL, 'F' }, { "interface", required_argument, NULL, 'i' }, { "nortnl", no_argument, NULL, 'n' }, { "nowiphy", no_argument, NULL, 'y' }, { "noscan", no_argument, NULL, 's' }, { "noies", no_argument, NULL, 'e' }, { "version", no_argument, NULL, 'v' }, { "help", no_argument, NULL, 'h' }, { } }; int main(int argc, char *argv[]) { const char *reader_path = NULL; const char *analyze_path = NULL; const char *ifname = NULL; int exit_status; for (;;) { int opt; opt = getopt_long(argc, argv, "r:w:a:i:nvhyse", main_options, NULL); if (opt < 0) break; switch (opt) { case 'r': reader_path = optarg; config.read_only = true; break; case 'w': writer_path = optarg; break; case 'a': analyze_path = optarg; break; case 'i': ifname = optarg; break; case 'n': config.nortnl = true; break; case 'y': config.nowiphy = true; break; case 's': config.noscan = true; break; case 'e': config.noies = true; break; case 'v': printf("%s\n", VERSION); return EXIT_SUCCESS; case 'h': usage(); return EXIT_SUCCESS; default: return EXIT_FAILURE; } } if (argc - optind > 0) { fprintf(stderr, "Invalid command line parameters\n"); return EXIT_FAILURE; } if (reader_path && analyze_path) { fprintf(stderr, "Display and analyze can't be combined\n"); return EXIT_FAILURE; } if (!l_main_init()) return EXIT_FAILURE; printf("Wireless monitor ver %s\n", VERSION); if (analyze_path) { exit_status = analyze_pcap(analyze_path); goto done; } if (reader_path) { struct pcap *pcap; open_pager(); pcap = pcap_open(reader_path); if (!pcap) { exit_status = EXIT_FAILURE; goto done; } if (pcap_get_type(pcap) != PCAP_TYPE_LINUX_SLL) { fprintf(stderr, "Invalid packet format\n"); exit_status = EXIT_FAILURE; } else exit_status = process_pcap(pcap, &config); pcap_close(pcap); close_pager(); goto done; } monitor_interface.ifname = l_strdup(ifname); iwmon_interface_lookup(&monitor_interface); exit_status = l_main_run_with_signal(signal_handler, NULL); l_io_destroy(monitor_interface.io); l_netlink_destroy(monitor_interface.rtnl); l_genl_unref(monitor_interface.genl); l_free(monitor_interface.ifname); nlmon_close(nlmon); done: l_timeout_remove(timeout); l_main_exit(); return exit_status; }