/* Copyright (C) 2007-2023 Open Information Security Foundation * * You can copy, redistribute or modify this Program under the terms of * the GNU General Public License version 2 as published by the Free * Software Foundation. * * 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 * version 2 along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA. */ /** * \file * * \author Victor Julien * \author Eric Leblond * * Netfilter's netfilter_queue support for reading packets from the * kernel and setting verdicts back to it (inline mode). */ #include "suricata-common.h" #include "suricata.h" #include "packet.h" #include "decode.h" #include "packet-queue.h" #include "threads.h" #include "threadvars.h" #include "tm-threads.h" #include "tm-queuehandlers.h" #include "tmqh-packetpool.h" #include "conf.h" #include "conf-yaml-loader.h" #include "source-nfq-prototypes.h" #include "action-globals.h" #include "util-datalink.h" #include "util-debug.h" #include "util-error.h" #include "util-byte.h" #include "util-cpu.h" #include "util-privs.h" #include "util-device.h" #include "runmodes.h" #include "source-nfq.h" /* Handle the case where no NFQ support is compiled in. */ #ifndef NFQ static TmEcode NoNFQSupportExit(ThreadVars *, const void *, void **); void TmModuleReceiveNFQRegister (void) { tmm_modules[TMM_RECEIVENFQ].name = "ReceiveNFQ"; tmm_modules[TMM_RECEIVENFQ].ThreadInit = NoNFQSupportExit; tmm_modules[TMM_RECEIVENFQ].ThreadExitPrintStats = NULL; tmm_modules[TMM_RECEIVENFQ].ThreadDeinit = NULL; tmm_modules[TMM_RECEIVENFQ].cap_flags = SC_CAP_NET_ADMIN; tmm_modules[TMM_RECEIVENFQ].flags = TM_FLAG_RECEIVE_TM; } void TmModuleVerdictNFQRegister (void) { tmm_modules[TMM_VERDICTNFQ].name = "VerdictNFQ"; tmm_modules[TMM_VERDICTNFQ].ThreadInit = NoNFQSupportExit; tmm_modules[TMM_VERDICTNFQ].ThreadExitPrintStats = NULL; tmm_modules[TMM_VERDICTNFQ].ThreadDeinit = NULL; tmm_modules[TMM_VERDICTNFQ].cap_flags = SC_CAP_NET_ADMIN; } void TmModuleDecodeNFQRegister (void) { tmm_modules[TMM_DECODENFQ].name = "DecodeNFQ"; tmm_modules[TMM_DECODENFQ].ThreadInit = NoNFQSupportExit; tmm_modules[TMM_DECODENFQ].ThreadExitPrintStats = NULL; tmm_modules[TMM_DECODENFQ].ThreadDeinit = NULL; tmm_modules[TMM_DECODENFQ].cap_flags = 0; tmm_modules[TMM_DECODENFQ].flags = TM_FLAG_DECODE_TM; } static TmEcode NoNFQSupportExit(ThreadVars *tv, const void *initdata, void **data) { FatalError("Error creating thread %s: you do not " "have support for nfqueue enabled please recompile with " "--enable-nfqueue", tv->name); } #else /* we do have NFQ support */ extern uint16_t max_pending_packets; #define MAX_ALREADY_TREATED 5 #define NFQ_VERDICT_RETRY_COUNT 3 static int already_seen_warning; static int runmode_workers; #define NFQ_BURST_FACTOR 4 #ifndef SOL_NETLINK #define SOL_NETLINK 270 #endif typedef struct NFQThreadVars_ { uint16_t nfq_index; ThreadVars *tv; TmSlot *slot; LiveDevice *livedev; char *data; /** Per function and thread data */ int datalen; /** Length of per function and thread data */ } NFQThreadVars; /* shared vars for all for nfq queues and threads */ static NFQGlobalVars nfq_g; static NFQThreadVars *g_nfq_t; static NFQQueueVars *g_nfq_q; static uint16_t receive_queue_num = 0; static SCMutex nfq_init_lock; static TmEcode ReceiveNFQLoop(ThreadVars *tv, void *data, void *slot); static TmEcode ReceiveNFQThreadInit(ThreadVars *, const void *, void **); static TmEcode ReceiveNFQThreadDeinit(ThreadVars *, void *); static void ReceiveNFQThreadExitStats(ThreadVars *, void *); static TmEcode VerdictNFQ(ThreadVars *, Packet *, void *); static TmEcode VerdictNFQThreadInit(ThreadVars *, const void *, void **); static TmEcode VerdictNFQThreadDeinit(ThreadVars *, void *); static TmEcode DecodeNFQ(ThreadVars *, Packet *, void *); static TmEcode DecodeNFQThreadInit(ThreadVars *, const void *, void **); static TmEcode DecodeNFQThreadDeinit(ThreadVars *tv, void *data); static TmEcode NFQSetVerdict(Packet *p); static void NFQReleasePacket(Packet *p); typedef enum NFQMode_ { NFQ_ACCEPT_MODE, NFQ_REPEAT_MODE, NFQ_ROUTE_MODE, } NFQMode; #define NFQ_FLAG_FAIL_OPEN (1 << 0) typedef struct NFQCnf_ { NFQMode mode; uint32_t mark; uint32_t mask; uint32_t bypass_mark; uint32_t bypass_mask; uint32_t next_queue; uint32_t flags; uint8_t batchcount; } NFQCnf; NFQCnf nfq_config; void TmModuleReceiveNFQRegister (void) { /* XXX create a general NFQ setup function */ memset(&nfq_g, 0, sizeof(nfq_g)); SCMutexInit(&nfq_init_lock, NULL); tmm_modules[TMM_RECEIVENFQ].name = "ReceiveNFQ"; tmm_modules[TMM_RECEIVENFQ].ThreadInit = ReceiveNFQThreadInit; tmm_modules[TMM_RECEIVENFQ].PktAcqLoop = ReceiveNFQLoop; tmm_modules[TMM_RECEIVENFQ].PktAcqBreakLoop = NULL; tmm_modules[TMM_RECEIVENFQ].ThreadExitPrintStats = ReceiveNFQThreadExitStats; tmm_modules[TMM_RECEIVENFQ].ThreadDeinit = ReceiveNFQThreadDeinit; tmm_modules[TMM_RECEIVENFQ].flags = TM_FLAG_RECEIVE_TM; } void TmModuleVerdictNFQRegister (void) { tmm_modules[TMM_VERDICTNFQ].name = "VerdictNFQ"; tmm_modules[TMM_VERDICTNFQ].ThreadInit = VerdictNFQThreadInit; tmm_modules[TMM_VERDICTNFQ].Func = VerdictNFQ; tmm_modules[TMM_VERDICTNFQ].ThreadDeinit = VerdictNFQThreadDeinit; } void TmModuleDecodeNFQRegister (void) { tmm_modules[TMM_DECODENFQ].name = "DecodeNFQ"; tmm_modules[TMM_DECODENFQ].ThreadInit = DecodeNFQThreadInit; tmm_modules[TMM_DECODENFQ].Func = DecodeNFQ; tmm_modules[TMM_DECODENFQ].ThreadDeinit = DecodeNFQThreadDeinit; tmm_modules[TMM_DECODENFQ].flags = TM_FLAG_DECODE_TM; } /** \brief To initialize the NFQ global configuration data * * \param quiet It tells the mode of operation, if it is TRUE nothing will * be get printed. */ void NFQInitConfig(bool quiet) { intmax_t value = 0; const char *nfq_mode = NULL; int boolval; SCLogDebug("Initializing NFQ"); memset(&nfq_config, 0, sizeof(nfq_config)); if ((ConfGet("nfq.mode", &nfq_mode)) == 0) { nfq_config.mode = NFQ_ACCEPT_MODE; } else { if (!strcmp("accept", nfq_mode)) { nfq_config.mode = NFQ_ACCEPT_MODE; } else if (!strcmp("repeat", nfq_mode)) { nfq_config.mode = NFQ_REPEAT_MODE; } else if (!strcmp("route", nfq_mode)) { nfq_config.mode = NFQ_ROUTE_MODE; } else { FatalError("Unknown nfq.mode"); } } (void)ConfGetBool("nfq.fail-open", (int *)&boolval); if (boolval) { #ifdef HAVE_NFQ_SET_QUEUE_FLAGS SCLogInfo("Enabling fail-open on queue"); nfq_config.flags |= NFQ_FLAG_FAIL_OPEN; #else SCLogError("nfq.%s set but NFQ library has no support for it.", "fail-open"); #endif } if ((ConfGetInt("nfq.repeat-mark", &value)) == 1) { nfq_config.mark = (uint32_t)value; } if ((ConfGetInt("nfq.repeat-mask", &value)) == 1) { nfq_config.mask = (uint32_t)value; } if ((ConfGetInt("nfq.bypass-mark", &value)) == 1) { nfq_config.bypass_mark = (uint32_t)value; } if ((ConfGetInt("nfq.bypass-mask", &value)) == 1) { nfq_config.bypass_mask = (uint32_t)value; } if ((ConfGetInt("nfq.route-queue", &value)) == 1) { nfq_config.next_queue = ((uint32_t)value) << 16; } if ((ConfGetInt("nfq.batchcount", &value)) == 1) { #ifdef HAVE_NFQ_SET_VERDICT_BATCH if (value > 255) { SCLogWarning("nfq.batchcount cannot exceed 255."); value = 255; } if (value > 1) nfq_config.batchcount = (uint8_t) (value - 1); #else SCLogWarning("nfq.%s set but NFQ library has no support for it.", "batchcount"); #endif } if (!quiet) { switch (nfq_config.mode) { case NFQ_ACCEPT_MODE: SCLogInfo("NFQ running in standard ACCEPT/DROP mode"); break; case NFQ_REPEAT_MODE: SCLogInfo("NFQ running in REPEAT mode with mark %"PRIu32"/%"PRIu32, nfq_config.mark, nfq_config.mask); break; case NFQ_ROUTE_MODE: SCLogInfo("NFQ running in route mode with next queue %"PRIu32, nfq_config.next_queue >> 16); break; } } } static uint8_t NFQVerdictCacheLen(NFQQueueVars *t) { #ifdef HAVE_NFQ_SET_VERDICT_BATCH return t->verdict_cache.len; #else return 0; #endif } static void NFQVerdictCacheFlush(NFQQueueVars *t) { #ifdef HAVE_NFQ_SET_VERDICT_BATCH int ret; int iter = 0; do { if (t->verdict_cache.mark_valid) ret = nfq_set_verdict_batch2(t->qh, t->verdict_cache.packet_id, t->verdict_cache.verdict, t->verdict_cache.mark); else ret = nfq_set_verdict_batch(t->qh, t->verdict_cache.packet_id, t->verdict_cache.verdict); } while ((ret < 0) && (iter++ < NFQ_VERDICT_RETRY_COUNT)); if (ret < 0) { SCLogWarning("nfq_set_verdict_batch failed: %s", strerror(errno)); } else { t->verdict_cache.len = 0; t->verdict_cache.mark_valid = 0; } #endif } static int NFQVerdictCacheAdd(NFQQueueVars *t, Packet *p, uint32_t verdict) { #ifdef HAVE_NFQ_SET_VERDICT_BATCH if (t->verdict_cache.maxlen == 0) return -1; if (p->flags & PKT_STREAM_MODIFIED || verdict == NF_DROP) goto flush; if (p->flags & PKT_MARK_MODIFIED) { if (!t->verdict_cache.mark_valid) { if (t->verdict_cache.len) goto flush; t->verdict_cache.mark_valid = 1; t->verdict_cache.mark = p->nfq_v.mark; } else if (t->verdict_cache.mark != p->nfq_v.mark) { goto flush; } } else if (t->verdict_cache.mark_valid) { goto flush; } if (t->verdict_cache.len == 0) { t->verdict_cache.verdict = verdict; } else if (t->verdict_cache.verdict != verdict) goto flush; /* same verdict, mark not set or identical -> can cache */ t->verdict_cache.packet_id = p->nfq_v.id; if (t->verdict_cache.len >= t->verdict_cache.maxlen) NFQVerdictCacheFlush(t); else t->verdict_cache.len++; return 0; flush: /* can't cache. Flush current cache and signal caller it should send single verdict */ if (NFQVerdictCacheLen(t) > 0) NFQVerdictCacheFlush(t); #endif return -1; } static inline void NFQMutexInit(NFQQueueVars *nq) { char *active_runmode = RunmodeGetActive(); if (active_runmode && !strcmp("workers", active_runmode)) { nq->use_mutex = 0; runmode_workers = 1; SCLogDebug("NFQ running in 'workers' runmode, will not use mutex."); } else { nq->use_mutex = 1; runmode_workers = 0; SCMutexInit(&nq->mutex_qh, NULL); } } #define NFQMutexLock(nq) do { \ if ((nq)->use_mutex) \ SCMutexLock(&(nq)->mutex_qh); \ } while (0) #define NFQMutexUnlock(nq) do { \ if ((nq)->use_mutex) \ SCMutexUnlock(&(nq)->mutex_qh); \ } while (0) /** * \brief Read data from nfq message and setup Packet * * \note * In case of error, this function verdict the packet * to avoid skb to get stuck in kernel. */ static int NFQSetupPkt (Packet *p, struct nfq_q_handle *qh, void *data) { struct nfq_data *tb = (struct nfq_data *)data; int ret; char *pktdata; struct nfqnl_msg_packet_hdr *ph; // Early release function -- will be updated once repeat // mode handling has been done p->ReleasePacket = PacketFreeOrRelease; ph = nfq_get_msg_packet_hdr(tb); if (ph != NULL) { p->nfq_v.id = SCNtohl(ph->packet_id); p->nfq_v.hw_protocol = ph->hw_protocol; } /* coverity[missing_lock] */ p->nfq_v.mark = nfq_get_nfmark(tb); if (nfq_config.mode == NFQ_REPEAT_MODE) { if ((nfq_config.mark & nfq_config.mask) == (p->nfq_v.mark & nfq_config.mask)) { int iter = 0; if (already_seen_warning < MAX_ALREADY_TREATED) SCLogInfo("Packet seems already treated by suricata"); already_seen_warning++; do { ret = nfq_set_verdict(qh, p->nfq_v.id, NF_ACCEPT, 0, NULL); } while ((ret < 0) && (iter++ < NFQ_VERDICT_RETRY_COUNT)); if (ret < 0) { SCLogWarning( "nfq_set_verdict of %p failed %" PRId32 ": %s", p, ret, strerror(errno)); } return -1 ; } } // Switch to full featured release function p->ReleasePacket = NFQReleasePacket; p->nfq_v.ifi = nfq_get_indev(tb); p->nfq_v.ifo = nfq_get_outdev(tb); p->nfq_v.verdicted = 0; #ifdef NFQ_GET_PAYLOAD_SIGNED ret = nfq_get_payload(tb, &pktdata); #else ret = nfq_get_payload(tb, (unsigned char **) &pktdata); #endif /* NFQ_GET_PAYLOAD_SIGNED */ if (ret > 0) { /* nfq_get_payload returns a pointer to a part of memory * that is not preserved over the lifetime of our packet. * So we need to copy it. */ if (ret > 65536) { /* Will not be able to copy data ! Set length to 0 * to trigger an error in packet decoding. * This is unlikely to happen */ SCLogWarning("NFQ sent too big packet"); SET_PKT_LEN(p, 0); } else if (runmode_workers) { PacketSetData(p, (uint8_t *)pktdata, ret); } else { PacketCopyData(p, (uint8_t *)pktdata, ret); } } else if (ret == -1) { /* unable to get pointer to data, ensure packet length is zero. * This will trigger an error in packet decoding */ SET_PKT_LEN(p, 0); } struct timeval tv; ret = nfq_get_timestamp(tb, &tv); if (ret != 0 || tv.tv_sec == 0) { memset(&tv, 0, sizeof(tv)); gettimeofday(&tv, NULL); } p->ts = SCTIME_FROM_TIMEVAL(&tv); p->datalink = DLT_RAW; return 0; } static void NFQReleasePacket(Packet *p) { if (unlikely(!p->nfq_v.verdicted)) { PacketDrop(p, ACTION_DROP, PKT_DROP_REASON_NFQ_ERROR); NFQSetVerdict(p); } PacketFreeOrRelease(p); } /** * \brief bypass callback function for NFQ * * \param p a Packet to use information from to trigger bypass * \return 1 if bypass is successful, 0 if not */ static int NFQBypassCallback(Packet *p) { if (IS_TUNNEL_PKT(p)) { /* real tunnels may have multiple flows inside them, so bypass can't * work for those. Rebuilt packets from IP fragments are fine. */ if (p->flags & PKT_REBUILT_FRAGMENT) { Packet *tp = p->root ? p->root : p; SCSpinLock(&tp->persistent.tunnel_lock); tp->nfq_v.mark = (nfq_config.bypass_mark & nfq_config.bypass_mask) | (tp->nfq_v.mark & ~nfq_config.bypass_mask); tp->flags |= PKT_MARK_MODIFIED; SCSpinUnlock(&tp->persistent.tunnel_lock); return 1; } return 0; } else { /* coverity[missing_lock] */ p->nfq_v.mark = (nfq_config.bypass_mark & nfq_config.bypass_mask) | (p->nfq_v.mark & ~nfq_config.bypass_mask); p->flags |= PKT_MARK_MODIFIED; } return 1; } static int NFQCallBack(struct nfq_q_handle *qh, struct nfgenmsg *nfmsg, struct nfq_data *nfa, void *data) { NFQThreadVars *ntv = (NFQThreadVars *)data; ThreadVars *tv = ntv->tv; int ret; /* grab a packet */ Packet *p = PacketGetFromQueueOrAlloc(); if (p == NULL) { return -1; } PKT_SET_SRC(p, PKT_SRC_WIRE); p->nfq_v.nfq_index = ntv->nfq_index; /* if bypass mask is set then we may want to bypass so set pointer */ if (nfq_config.bypass_mask) { p->BypassPacketsFlow = NFQBypassCallback; } ret = NFQSetupPkt(p, qh, (void *)nfa); if (ret == -1) { #ifdef COUNTERS NFQQueueVars *q = NFQGetQueue(ntv->nfq_index); q->errs++; q->pkts++; q->bytes += GET_PKT_LEN(p); #endif /* COUNTERS */ (void) SC_ATOMIC_ADD(ntv->livedev->pkts, 1); /* NFQSetupPkt is issuing a verdict so we only recycle Packet and leave */ TmqhOutputPacketpool(tv, p); return 0; } #ifdef COUNTERS NFQQueueVars *q = NFQGetQueue(ntv->nfq_index); q->pkts++; q->bytes += GET_PKT_LEN(p); #endif /* COUNTERS */ (void) SC_ATOMIC_ADD(ntv->livedev->pkts, 1); if (TmThreadsSlotProcessPkt(tv, ntv->slot, p) != TM_ECODE_OK) { return -1; } return 0; } static TmEcode NFQInitThread(NFQThreadVars *t, uint32_t queue_maxlen) { struct timeval tv; int opt; NFQQueueVars *q = NFQGetQueue(t->nfq_index); if (q == NULL) { SCLogError("no queue for given index"); return TM_ECODE_FAILED; } SCLogDebug("opening library handle"); q->h = nfq_open(); if (q->h == NULL) { SCLogError("nfq_open() failed"); return TM_ECODE_FAILED; } if (nfq_g.unbind == 0) { /* VJ: on my Ubuntu Hardy system this fails the first time it's * run. Ignoring the error seems to have no bad effects. */ SCLogDebug("unbinding existing nf_queue handler for AF_INET (if any)"); if (nfq_unbind_pf(q->h, AF_INET) < 0) { FatalError("nfq_unbind_pf() for AF_INET failed: %s", strerror(errno)); } if (nfq_unbind_pf(q->h, AF_INET6) < 0) { FatalError("nfq_unbind_pf() for AF_INET6 failed"); } nfq_g.unbind = 1; SCLogDebug("binding nfnetlink_queue as nf_queue handler for AF_INET and AF_INET6"); if (nfq_bind_pf(q->h, AF_INET) < 0) { FatalError("nfq_bind_pf() for AF_INET failed"); } if (nfq_bind_pf(q->h, AF_INET6) < 0) { FatalError("nfq_bind_pf() for AF_INET6 failed"); } } SCLogInfo("binding this thread %d to queue '%" PRIu32 "'", t->nfq_index, q->queue_num); /* pass the thread memory as a void ptr so the * callback function has access to it. */ q->qh = nfq_create_queue(q->h, q->queue_num, &NFQCallBack, (void *)t); if (q->qh == NULL) { SCLogError("nfq_create_queue failed"); return TM_ECODE_FAILED; } SCLogDebug("setting copy_packet mode"); /* 05DC = 1500 */ //if (nfq_set_mode(nfq_t->qh, NFQNL_COPY_PACKET, 0x05DC) < 0) { if (nfq_set_mode(q->qh, NFQNL_COPY_PACKET, 0xFFFF) < 0) { SCLogError("can't set packet_copy mode"); return TM_ECODE_FAILED; } #ifdef HAVE_NFQ_MAXLEN if (queue_maxlen > 0) { SCLogInfo("setting queue length to %" PRId32 "", queue_maxlen); /* non-fatal if it fails */ if (nfq_set_queue_maxlen(q->qh, queue_maxlen) < 0) { SCLogWarning("can't set queue maxlen: your kernel probably " "doesn't support setting the queue length"); } } #endif /* HAVE_NFQ_MAXLEN */ /* set netlink buffer size to a decent value */ nfnl_rcvbufsiz(nfq_nfnlh(q->h), queue_maxlen * 1500); SCLogInfo("setting nfnl bufsize to %" PRId32 "", queue_maxlen * 1500); q->nh = nfq_nfnlh(q->h); q->fd = nfnl_fd(q->nh); NFQMutexInit(q); /* Set some netlink specific option on the socket to increase performance */ opt = 1; #ifdef NETLINK_BROADCAST_SEND_ERROR if (setsockopt(q->fd, SOL_NETLINK, NETLINK_BROADCAST_SEND_ERROR, &opt, sizeof(int)) == -1) { SCLogWarning("can't set netlink broadcast error: %s", strerror(errno)); } #endif /* Don't send error about no buffer space available but drop the packets instead */ #ifdef NETLINK_NO_ENOBUFS if (setsockopt(q->fd, SOL_NETLINK, NETLINK_NO_ENOBUFS, &opt, sizeof(int)) == -1) { SCLogWarning("can't set netlink enobufs: %s", strerror(errno)); } #endif #ifdef HAVE_NFQ_SET_QUEUE_FLAGS if (nfq_config.flags & NFQ_FLAG_FAIL_OPEN) { uint32_t flags = NFQA_CFG_F_FAIL_OPEN; uint32_t mask = NFQA_CFG_F_FAIL_OPEN; int r = nfq_set_queue_flags(q->qh, mask, flags); if (r == -1) { SCLogWarning("can't set fail-open mode: %s", strerror(errno)); } else { SCLogInfo("fail-open mode should be set on queue"); } } #endif #ifdef HAVE_NFQ_SET_VERDICT_BATCH if (runmode_workers) { q->verdict_cache.maxlen = nfq_config.batchcount; } else if (nfq_config.batchcount) { SCLogError("nfq.batchcount is only valid in workers runmode."); } #endif /* set a timeout to the socket so we can check for a signal * in case we don't get packets for a longer period. */ tv.tv_sec = 1; tv.tv_usec = 0; if(setsockopt(q->fd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)) == -1) { SCLogWarning("can't set socket timeout: %s", strerror(errno)); } SCLogDebug("nfq_q->h %p, nfq_q->nh %p, nfq_q->qh %p, nfq_q->fd %" PRId32 "", q->h, q->nh, q->qh, q->fd); return TM_ECODE_OK; } TmEcode ReceiveNFQThreadInit(ThreadVars *tv, const void *initdata, void **data) { SCMutexLock(&nfq_init_lock); sigset_t sigs; sigfillset(&sigs); pthread_sigmask(SIG_BLOCK, &sigs, NULL); NFQThreadVars *ntv = (NFQThreadVars *) initdata; /* store the ThreadVars pointer in our NFQ thread context * as we will need it in our callback function */ ntv->tv = tv; int r = NFQInitThread(ntv, (max_pending_packets * NFQ_BURST_FACTOR)); if (r != TM_ECODE_OK) { SCLogError("nfq thread failed to initialize"); SCMutexUnlock(&nfq_init_lock); exit(EXIT_FAILURE); } #define T_DATA_SIZE 70000 ntv->data = SCMalloc(T_DATA_SIZE); if (ntv->data == NULL) { SCMutexUnlock(&nfq_init_lock); return TM_ECODE_FAILED; } ntv->datalen = T_DATA_SIZE; #undef T_DATA_SIZE DatalinkSetGlobalType(DLT_RAW); *data = (void *)ntv; SCMutexUnlock(&nfq_init_lock); return TM_ECODE_OK; } static void NFQDestroyQueue(NFQQueueVars *nq) { if (unlikely(nq == NULL)) { return; } SCLogDebug("starting... will close queuenum %" PRIu32 "", nq->queue_num); NFQMutexLock(nq); if (nq->qh != NULL) { nfq_destroy_queue(nq->qh); nq->qh = NULL; nfq_close(nq->h); nq->h = NULL; } NFQMutexUnlock(nq); } TmEcode ReceiveNFQThreadDeinit(ThreadVars *t, void *data) { NFQThreadVars *ntv = (NFQThreadVars *)data; NFQQueueVars *nq = NFQGetQueue(ntv->nfq_index); if (ntv->data != NULL) { SCFree(ntv->data); ntv->data = NULL; } ntv->datalen = 0; NFQDestroyQueue(nq); return TM_ECODE_OK; } TmEcode VerdictNFQThreadInit(ThreadVars *tv, const void *initdata, void **data) { NFQThreadVars *ntv = (NFQThreadVars *)initdata; *data = (void *)ntv; return TM_ECODE_OK; } TmEcode VerdictNFQThreadDeinit(ThreadVars *tv, void *data) { NFQThreadVars *ntv = (NFQThreadVars *)data; NFQQueueVars *nq = NFQGetQueue(ntv->nfq_index); NFQDestroyQueue(nq); return TM_ECODE_OK; } /** * \brief Add a single Netfilter queue * * \param string with the queue number * * \retval 0 on success. * \retval -1 on failure. */ int NFQRegisterQueue(const uint16_t number) { NFQThreadVars *ntv = NULL; NFQQueueVars *nq = NULL; char queue[10] = { 0 }; static bool many_queues_warned = false; uint16_t num_cpus = UtilCpuGetNumProcessorsOnline(); if (g_nfq_t == NULL || g_nfq_q == NULL) { SCLogError("NFQ context is not initialized"); return -1; } SCMutexLock(&nfq_init_lock); if (!many_queues_warned && (receive_queue_num >= num_cpus)) { SCLogWarning("using more Netfilter queues than %hu available CPU core(s) " "may degrade performance", num_cpus); many_queues_warned = true; } if (receive_queue_num >= NFQ_MAX_QUEUE) { SCLogError("can not register more than %d Netfilter queues", NFQ_MAX_QUEUE); SCMutexUnlock(&nfq_init_lock); return -1; } ntv = &g_nfq_t[receive_queue_num]; ntv->nfq_index = receive_queue_num; nq = &g_nfq_q[receive_queue_num]; memset(nq, 0, sizeof(*nq)); nq->queue_num = number; receive_queue_num++; SCMutexUnlock(&nfq_init_lock); snprintf(queue, sizeof(queue) - 1, "NFQ#%hu", number); LiveRegisterDevice(queue); ntv->livedev = LiveGetDevice(queue); if (ntv->livedev == NULL) { SCLogError("Unable to find Live device"); return -1; } SCLogDebug("Queue %d registered.", number); return 0; } /** * \brief Parses and adds Netfilter queue(s). * * \param string with the queue number or range * * \retval 0 on success. * \retval -1 on failure. */ int NFQParseAndRegisterQueues(const char *queues) { uint16_t queue_start = 0; uint16_t queue_end = 0; uint16_t num_queues = 1; // if argument is correct, at least one queue will be created // Either "id" or "start:end" format (e.g., "12" or "0:5") int count = sscanf(queues, "%hu:%hu", &queue_start, &queue_end); if (count < 1) { SCLogError("specified queue(s) argument '%s' is not " "valid (allowed queue numbers are 0-65535)", queues); return -1; } // Do we have a range? if (count == 2) { // Sanity check if (queue_start > queue_end) { SCLogError("start queue's number %d is greater than " "ending number %d", queue_start, queue_end); return -1; } num_queues = queue_end - queue_start + 1; // +1 due to inclusive range } // We do realloc() to preserve previously registered queues void *ptmp = SCRealloc(g_nfq_t, (receive_queue_num + num_queues) * sizeof(NFQThreadVars)); if (ptmp == NULL) { SCLogError("Unable to allocate NFQThreadVars"); NFQContextsClean(); exit(EXIT_FAILURE); } g_nfq_t = (NFQThreadVars *)ptmp; ptmp = SCRealloc(g_nfq_q, (receive_queue_num + num_queues) * sizeof(NFQQueueVars)); if (ptmp == NULL) { SCLogError("Unable to allocate NFQQueueVars"); NFQContextsClean(); exit(EXIT_FAILURE); } g_nfq_q = (NFQQueueVars *)ptmp; do { if (NFQRegisterQueue(queue_start) != 0) { return -1; } } while (++queue_start <= queue_end); return 0; } /** * \brief Get a pointer to the NFQ queue at index * * \param number idx of the queue in our array * * \retval ptr pointer to the NFQThreadVars at index * \retval NULL on error */ void *NFQGetQueue(int number) { if (unlikely(number < 0 || number >= receive_queue_num || g_nfq_q == NULL)) return NULL; return (void *)&g_nfq_q[number]; } /** * \brief Get a pointer to the NFQ thread at index * * This function is temporary used as configuration parser. * * \param number idx of the queue in our array * * \retval ptr pointer to the NFQThreadVars at index * \retval NULL on error */ void *NFQGetThread(int number) { if (unlikely(number < 0 || number >= receive_queue_num || g_nfq_t == NULL)) return NULL; return (void *)&g_nfq_t[number]; } /** * \brief NFQ function to get a packet from the kernel * * \note separate functions for Linux and Win32 for readability. */ static void NFQRecvPkt(NFQQueueVars *t, NFQThreadVars *tv) { int ret; int flag = NFQVerdictCacheLen(t) ? MSG_DONTWAIT : 0; int rv = recv(t->fd, tv->data, tv->datalen, flag); if (rv < 0) { if (errno == EINTR || errno == EWOULDBLOCK || errno == EAGAIN) { /* no error on timeout */ if (flag) NFQVerdictCacheFlush(t); /* handle timeout */ TmThreadsCaptureHandleTimeout(tv->tv, NULL); } else { #ifdef COUNTERS NFQMutexLock(t); t->errs++; NFQMutexUnlock(t); #endif /* COUNTERS */ } } else if(rv == 0) { SCLogWarning("recv got returncode 0"); } else { #ifdef DBG_PERF if (rv > t->dbg_maxreadsize) t->dbg_maxreadsize = rv; #endif /* DBG_PERF */ NFQMutexLock(t); if (t->qh != NULL) { ret = nfq_handle_packet(t->h, tv->data, rv); } else { SCLogWarning("NFQ handle has been destroyed"); ret = -1; } NFQMutexUnlock(t); if (ret != 0) { SCLogDebug("nfq_handle_packet error %"PRId32, ret); } } } /** * \brief Main NFQ reading Loop function */ TmEcode ReceiveNFQLoop(ThreadVars *tv, void *data, void *slot) { SCEnter(); NFQThreadVars *ntv = (NFQThreadVars *)data; NFQQueueVars *nq = NFQGetQueue(ntv->nfq_index); ntv->slot = ((TmSlot *) slot)->slot_next; // Indicate that the thread is actually running its application level code (i.e., it can poll // packets) TmThreadsSetFlag(tv, THV_RUNNING); while(1) { if (unlikely(suricata_ctl_flags != 0)) { NFQDestroyQueue(nq); break; } NFQRecvPkt(nq, ntv); StatsSyncCountersIfSignalled(tv); } SCReturnInt(TM_ECODE_OK); } /** * \brief NFQ receive module stats printing function */ void ReceiveNFQThreadExitStats(ThreadVars *tv, void *data) { NFQThreadVars *ntv = (NFQThreadVars *)data; NFQQueueVars *nq = NFQGetQueue(ntv->nfq_index); #ifdef COUNTERS SCLogNotice("(%s) Treated: Pkts %" PRIu32 ", Bytes %" PRIu64 ", Errors %" PRIu32 "", tv->name, nq->pkts, nq->bytes, nq->errs); SCLogNotice("(%s) Verdict: Accepted %"PRIu32", Dropped %"PRIu32", Replaced %"PRIu32, tv->name, nq->accepted, nq->dropped, nq->replaced); #endif } static inline uint32_t GetVerdict(const Packet *p) { uint32_t verdict = NF_ACCEPT; if (PacketCheckAction(p, ACTION_DROP)) { verdict = NF_DROP; } else { switch (nfq_config.mode) { default: case NFQ_ACCEPT_MODE: verdict = NF_ACCEPT; break; case NFQ_REPEAT_MODE: verdict = NF_REPEAT; break; case NFQ_ROUTE_MODE: verdict = ((uint32_t) NF_QUEUE) | nfq_config.next_queue; break; } } return verdict; } #ifdef COUNTERS static inline void UpdateCounters(NFQQueueVars *t, const Packet *p) { if (PacketCheckAction(p, ACTION_DROP)) { t->dropped++; } else { if (p->flags & PKT_STREAM_MODIFIED) { t->replaced++; } t->accepted++; } } #endif /* COUNTERS */ /** * \brief NFQ verdict function */ TmEcode NFQSetVerdict(Packet *p) { int iter = 0; /* we could also have a direct pointer but we need to have a ref count in this case */ NFQQueueVars *t = g_nfq_q + p->nfq_v.nfq_index; p->nfq_v.verdicted = 1; /* can't verdict a "fake" packet */ if (PKT_IS_PSEUDOPKT(p)) { return TM_ECODE_OK; } //printf("%p verdicting on queue %" PRIu32 "\n", t, t->queue_num); NFQMutexLock(t); if (t->qh == NULL) { /* Somebody has started a clean-up, we leave */ NFQMutexUnlock(t); return TM_ECODE_OK; } uint32_t verdict = GetVerdict(p); #ifdef COUNTERS UpdateCounters(t, p); #endif /* COUNTERS */ int ret = NFQVerdictCacheAdd(t, p, verdict); if (ret == 0) { NFQMutexUnlock(t); return TM_ECODE_OK; } do { switch (nfq_config.mode) { default: case NFQ_ACCEPT_MODE: case NFQ_ROUTE_MODE: if (p->flags & PKT_MARK_MODIFIED) { #ifdef HAVE_NFQ_SET_VERDICT2 if (p->flags & PKT_STREAM_MODIFIED) { ret = nfq_set_verdict2(t->qh, p->nfq_v.id, verdict, p->nfq_v.mark, GET_PKT_LEN(p), GET_PKT_DATA(p)); } else { ret = nfq_set_verdict2(t->qh, p->nfq_v.id, verdict, p->nfq_v.mark, 0, NULL); } #else /* fall back to old function */ if (p->flags & PKT_STREAM_MODIFIED) { ret = nfq_set_verdict_mark(t->qh, p->nfq_v.id, verdict, htonl(p->nfq_v.mark), GET_PKT_LEN(p), GET_PKT_DATA(p)); } else { ret = nfq_set_verdict_mark(t->qh, p->nfq_v.id, verdict, htonl(p->nfq_v.mark), 0, NULL); } #endif /* HAVE_NFQ_SET_VERDICT2 */ } else { if (p->flags & PKT_STREAM_MODIFIED) { ret = nfq_set_verdict(t->qh, p->nfq_v.id, verdict, GET_PKT_LEN(p), GET_PKT_DATA(p)); } else { ret = nfq_set_verdict(t->qh, p->nfq_v.id, verdict, 0, NULL); } } break; case NFQ_REPEAT_MODE: #ifdef HAVE_NFQ_SET_VERDICT2 if (p->flags & PKT_STREAM_MODIFIED) { ret = nfq_set_verdict2(t->qh, p->nfq_v.id, verdict, (nfq_config.mark & nfq_config.mask) | (p->nfq_v.mark & ~nfq_config.mask), GET_PKT_LEN(p), GET_PKT_DATA(p)); } else { ret = nfq_set_verdict2(t->qh, p->nfq_v.id, verdict, (nfq_config.mark & nfq_config.mask) | (p->nfq_v.mark & ~nfq_config.mask), 0, NULL); } #else /* fall back to old function */ if (p->flags & PKT_STREAM_MODIFIED) { ret = nfq_set_verdict_mark(t->qh, p->nfq_v.id, verdict, htonl((nfq_config.mark & nfq_config.mask) | (p->nfq_v.mark & ~nfq_config.mask)), GET_PKT_LEN(p), GET_PKT_DATA(p)); } else { ret = nfq_set_verdict_mark(t->qh, p->nfq_v.id, verdict, htonl((nfq_config.mark & nfq_config.mask) | (p->nfq_v.mark & ~nfq_config.mask)), 0, NULL); } #endif /* HAVE_NFQ_SET_VERDICT2 */ break; } } while ((ret < 0) && (iter++ < NFQ_VERDICT_RETRY_COUNT)); NFQMutexUnlock(t); if (ret < 0) { SCLogWarning("nfq_set_verdict of %p failed %" PRId32 ": %s", p, ret, strerror(errno)); return TM_ECODE_FAILED; } return TM_ECODE_OK; } /** * \brief NFQ verdict module packet entry function */ TmEcode VerdictNFQ(ThreadVars *tv, Packet *p, void *data) { /* if this is a tunnel packet we check if we are ready to verdict * already. */ if (IS_TUNNEL_PKT(p)) { SCLogDebug("tunnel pkt: %p/%p %s", p, p->root, p->root ? "upper layer" : "root"); bool verdict = VerdictTunnelPacket(p); /* don't verdict if we are not ready */ if (verdict == true) { int ret = NFQSetVerdict(p->root ? p->root : p); if (ret != TM_ECODE_OK) { return ret; } } } else { /* no tunnel, verdict normally */ int ret = NFQSetVerdict(p); if (ret != TM_ECODE_OK) { return ret; } } return TM_ECODE_OK; } /** * \brief Decode a packet coming from NFQ */ TmEcode DecodeNFQ(ThreadVars *tv, Packet *p, void *data) { IPV4Hdr *ip4h = (IPV4Hdr *)GET_PKT_DATA(p); IPV6Hdr *ip6h = (IPV6Hdr *)GET_PKT_DATA(p); DecodeThreadVars *dtv = (DecodeThreadVars *)data; BUG_ON(PKT_IS_PSEUDOPKT(p)); DecodeUpdatePacketCounters(tv, dtv, p); if (IPV4_GET_RAW_VER(ip4h) == 4) { if (unlikely(GET_PKT_LEN(p) > USHRT_MAX)) { return TM_ECODE_FAILED; } SCLogDebug("IPv4 packet"); DecodeIPV4(tv, dtv, p, GET_PKT_DATA(p), GET_PKT_LEN(p)); } else if (IPV6_GET_RAW_VER(ip6h) == 6) { if (unlikely(GET_PKT_LEN(p) > USHRT_MAX)) { return TM_ECODE_FAILED; } SCLogDebug("IPv6 packet"); DecodeIPV6(tv, dtv, p, GET_PKT_DATA(p), GET_PKT_LEN(p)); } else { SCLogDebug("packet unsupported by NFQ, first byte: %02x", *GET_PKT_DATA(p)); } PacketDecodeFinalize(tv, dtv, p); return TM_ECODE_OK; } /** * \brief Initialize the NFQ Decode threadvars */ TmEcode DecodeNFQThreadInit(ThreadVars *tv, const void *initdata, void **data) { DecodeThreadVars *dtv = DecodeThreadVarsAlloc(tv); if (dtv == NULL) SCReturnInt(TM_ECODE_FAILED); DecodeRegisterPerfCounters(dtv, tv); *data = (void *)dtv; return TM_ECODE_OK; } TmEcode DecodeNFQThreadDeinit(ThreadVars *tv, void *data) { if (data != NULL) DecodeThreadVarsFree(tv, data); SCReturnInt(TM_ECODE_OK); } /** * \brief Clean global contexts. Must be called on exit. */ void NFQContextsClean(void) { if (g_nfq_q != NULL) { SCFree(g_nfq_q); g_nfq_q = NULL; } if (g_nfq_t != NULL) { SCFree(g_nfq_t); g_nfq_t = NULL; } } #endif /* NFQ */