/*- * Copyright (c) 2010-2011 Alexander V. Chernikov * Copyright (c) 2004-2005 Gleb Smirnoff * Copyright (c) 2001-2003 Roman V. Palagin * 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. * * $SourceForge: netflow.c,v 1.41 2004/09/05 11:41:10 glebius Exp $ */ #include __FBSDID("$FreeBSD$"); #include "opt_inet6.h" #include "opt_route.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define NBUCKETS (65536) /* must be power of 2 */ /* This hash is for TCP or UDP packets. */ #define FULL_HASH(addr1, addr2, port1, port2) \ (((addr1 ^ (addr1 >> 16) ^ \ htons(addr2 ^ (addr2 >> 16))) ^ \ port1 ^ htons(port2)) & \ (NBUCKETS - 1)) /* This hash is for all other IP packets. */ #define ADDR_HASH(addr1, addr2) \ ((addr1 ^ (addr1 >> 16) ^ \ htons(addr2 ^ (addr2 >> 16))) & \ (NBUCKETS - 1)) /* Macros to shorten logical constructions */ /* XXX: priv must exist in namespace */ #define INACTIVE(fle) (time_uptime - fle->f.last > priv->info.nfinfo_inact_t) #define AGED(fle) (time_uptime - fle->f.first > priv->info.nfinfo_act_t) #define ISFREE(fle) (fle->f.packets == 0) /* * 4 is a magical number: statistically number of 4-packet flows is * bigger than 5,6,7...-packet flows by an order of magnitude. Most UDP/ICMP * scans are 1 packet (~ 90% of flow cache). TCP scans are 2-packet in case * of reachable host and 4-packet otherwise. */ #define SMALL(fle) (fle->f.packets <= 4) MALLOC_DEFINE(M_NETFLOW_HASH, "netflow_hash", "NetFlow hash"); static int export_add(item_p, struct flow_entry *); static int export_send(priv_p, fib_export_p, item_p, int); static int hash_insert(priv_p, struct flow_hash_entry *, struct flow_rec *, int, uint8_t, uint8_t); #ifdef INET6 static int hash6_insert(priv_p, struct flow_hash_entry *, struct flow6_rec *, int, uint8_t, uint8_t); #endif static void expire_flow(priv_p, fib_export_p, struct flow_entry *, int); /* * Generate hash for a given flow record. * * FIB is not used here, because: * most VRFS will carry public IPv4 addresses which are unique even * without FIB private addresses can overlap, but this is worked out * via flow_rec bcmp() containing fib id. In IPv6 world addresses are * all globally unique (it's not fully true, there is FC00::/7 for example, * but chances of address overlap are MUCH smaller) */ static inline uint32_t ip_hash(struct flow_rec *r) { switch (r->r_ip_p) { case IPPROTO_TCP: case IPPROTO_UDP: return FULL_HASH(r->r_src.s_addr, r->r_dst.s_addr, r->r_sport, r->r_dport); default: return ADDR_HASH(r->r_src.s_addr, r->r_dst.s_addr); } } #ifdef INET6 /* Generate hash for a given flow6 record. Use lower 4 octets from v6 addresses */ static inline uint32_t ip6_hash(struct flow6_rec *r) { switch (r->r_ip_p) { case IPPROTO_TCP: case IPPROTO_UDP: return FULL_HASH(r->src.r_src6.__u6_addr.__u6_addr32[3], r->dst.r_dst6.__u6_addr.__u6_addr32[3], r->r_sport, r->r_dport); default: return ADDR_HASH(r->src.r_src6.__u6_addr.__u6_addr32[3], r->dst.r_dst6.__u6_addr.__u6_addr32[3]); } } #endif /* This is callback from uma(9), called on alloc. */ static int uma_ctor_flow(void *mem, int size, void *arg, int how) { priv_p priv = (priv_p )arg; if (atomic_load_acq_32(&priv->info.nfinfo_used) >= CACHESIZE) return (ENOMEM); atomic_add_32(&priv->info.nfinfo_used, 1); return (0); } /* This is callback from uma(9), called on free. */ static void uma_dtor_flow(void *mem, int size, void *arg) { priv_p priv = (priv_p )arg; atomic_subtract_32(&priv->info.nfinfo_used, 1); } #ifdef INET6 /* This is callback from uma(9), called on alloc. */ static int uma_ctor_flow6(void *mem, int size, void *arg, int how) { priv_p priv = (priv_p )arg; if (atomic_load_acq_32(&priv->info.nfinfo_used6) >= CACHESIZE) return (ENOMEM); atomic_add_32(&priv->info.nfinfo_used6, 1); return (0); } /* This is callback from uma(9), called on free. */ static void uma_dtor_flow6(void *mem, int size, void *arg) { priv_p priv = (priv_p )arg; atomic_subtract_32(&priv->info.nfinfo_used6, 1); } #endif /* * Detach export datagram from priv, if there is any. * If there is no, allocate a new one. */ static item_p get_export_dgram(priv_p priv, fib_export_p fe) { item_p item = NULL; mtx_lock(&fe->export_mtx); if (fe->exp.item != NULL) { item = fe->exp.item; fe->exp.item = NULL; } mtx_unlock(&fe->export_mtx); if (item == NULL) { struct netflow_v5_export_dgram *dgram; struct mbuf *m; m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); if (m == NULL) return (NULL); item = ng_package_data(m, NG_NOFLAGS); if (item == NULL) return (NULL); dgram = mtod(m, struct netflow_v5_export_dgram *); dgram->header.count = 0; dgram->header.version = htons(NETFLOW_V5); dgram->header.pad = 0; } return (item); } /* * Re-attach incomplete datagram back to priv. * If there is already another one, then send incomplete. */ static void return_export_dgram(priv_p priv, fib_export_p fe, item_p item, int flags) { /* * It may happen on SMP, that some thread has already * put its item there, in this case we bail out and * send what we have to collector. */ mtx_lock(&fe->export_mtx); if (fe->exp.item == NULL) { fe->exp.item = item; mtx_unlock(&fe->export_mtx); } else { mtx_unlock(&fe->export_mtx); export_send(priv, fe, item, flags); } } /* * The flow is over. Call export_add() and free it. If datagram is * full, then call export_send(). */ static void expire_flow(priv_p priv, fib_export_p fe, struct flow_entry *fle, int flags) { struct netflow_export_item exp; uint16_t version = fle->f.version; if ((priv->export != NULL) && (version == IPVERSION)) { exp.item = get_export_dgram(priv, fe); if (exp.item == NULL) { atomic_add_32(&priv->info.nfinfo_export_failed, 1); if (priv->export9 != NULL) atomic_add_32(&priv->info.nfinfo_export9_failed, 1); /* fle definitely contains IPv4 flow. */ uma_zfree_arg(priv->zone, fle, priv); return; } if (export_add(exp.item, fle) > 0) export_send(priv, fe, exp.item, flags); else return_export_dgram(priv, fe, exp.item, NG_QUEUE); } if (priv->export9 != NULL) { exp.item9 = get_export9_dgram(priv, fe, &exp.item9_opt); if (exp.item9 == NULL) { atomic_add_32(&priv->info.nfinfo_export9_failed, 1); if (version == IPVERSION) uma_zfree_arg(priv->zone, fle, priv); #ifdef INET6 else if (version == IP6VERSION) uma_zfree_arg(priv->zone6, fle, priv); #endif else panic("ng_netflow: Unknown IP proto: %d", version); return; } if (export9_add(exp.item9, exp.item9_opt, fle) > 0) export9_send(priv, fe, exp.item9, exp.item9_opt, flags); else return_export9_dgram(priv, fe, exp.item9, exp.item9_opt, NG_QUEUE); } if (version == IPVERSION) uma_zfree_arg(priv->zone, fle, priv); #ifdef INET6 else if (version == IP6VERSION) uma_zfree_arg(priv->zone6, fle, priv); #endif } /* Get a snapshot of node statistics */ void ng_netflow_copyinfo(priv_p priv, struct ng_netflow_info *i) { /* XXX: atomic */ memcpy((void *)i, (void *)&priv->info, sizeof(priv->info)); } /* * Insert a record into defined slot. * * First we get for us a free flow entry, then fill in all * possible fields in it. * * TODO: consider dropping hash mutex while filling in datagram, * as this was done in previous version. Need to test & profile * to be sure. */ static int hash_insert(priv_p priv, struct flow_hash_entry *hsh, struct flow_rec *r, int plen, uint8_t flags, uint8_t tcp_flags) { struct flow_entry *fle; struct sockaddr_in sin; struct rtentry *rt; mtx_assert(&hsh->mtx, MA_OWNED); fle = uma_zalloc_arg(priv->zone, priv, M_NOWAIT); if (fle == NULL) { atomic_add_32(&priv->info.nfinfo_alloc_failed, 1); return (ENOMEM); } /* * Now fle is totally ours. It is detached from all lists, * we can safely edit it. */ fle->f.version = IPVERSION; bcopy(r, &fle->f.r, sizeof(struct flow_rec)); fle->f.bytes = plen; fle->f.packets = 1; fle->f.tcp_flags = tcp_flags; fle->f.first = fle->f.last = time_uptime; /* * First we do route table lookup on destination address. So we can * fill in out_ifx, dst_mask, nexthop, and dst_as in future releases. */ if ((flags & NG_NETFLOW_CONF_NODSTLOOKUP) == 0) { bzero(&sin, sizeof(sin)); sin.sin_len = sizeof(struct sockaddr_in); sin.sin_family = AF_INET; sin.sin_addr = fle->f.r.r_dst; rt = rtalloc1_fib((struct sockaddr *)&sin, 0, 0, r->fib); if (rt != NULL) { fle->f.fle_o_ifx = rt->rt_ifp->if_index; if (rt->rt_flags & RTF_GATEWAY && rt->rt_gateway->sa_family == AF_INET) fle->f.next_hop = ((struct sockaddr_in *)(rt->rt_gateway))->sin_addr; if (rt_mask(rt)) fle->f.dst_mask = bitcount32(((struct sockaddr_in *)rt_mask(rt))->sin_addr.s_addr); else if (rt->rt_flags & RTF_HOST) /* Give up. We can't determine mask :( */ fle->f.dst_mask = 32; RTFREE_LOCKED(rt); } } /* Do route lookup on source address, to fill in src_mask. */ if ((flags & NG_NETFLOW_CONF_NOSRCLOOKUP) == 0) { bzero(&sin, sizeof(sin)); sin.sin_len = sizeof(struct sockaddr_in); sin.sin_family = AF_INET; sin.sin_addr = fle->f.r.r_src; rt = rtalloc1_fib((struct sockaddr *)&sin, 0, 0, r->fib); if (rt != NULL) { if (rt_mask(rt)) fle->f.src_mask = bitcount32(((struct sockaddr_in *)rt_mask(rt))->sin_addr.s_addr); else if (rt->rt_flags & RTF_HOST) /* Give up. We can't determine mask :( */ fle->f.src_mask = 32; RTFREE_LOCKED(rt); } } /* Push new flow at the and of hash. */ TAILQ_INSERT_TAIL(&hsh->head, fle, fle_hash); return (0); } #ifdef INET6 /* XXX: make normal function, instead of.. */ #define ipv6_masklen(x) bitcount32((x).__u6_addr.__u6_addr32[0]) + \ bitcount32((x).__u6_addr.__u6_addr32[1]) + \ bitcount32((x).__u6_addr.__u6_addr32[2]) + \ bitcount32((x).__u6_addr.__u6_addr32[3]) #define RT_MASK6(x) (ipv6_masklen(((struct sockaddr_in6 *)rt_mask(x))->sin6_addr)) static int hash6_insert(priv_p priv, struct flow_hash_entry *hsh6, struct flow6_rec *r, int plen, uint8_t flags, uint8_t tcp_flags) { struct flow6_entry *fle6; struct sockaddr_in6 *src, *dst; struct rtentry *rt; struct route_in6 rin6; mtx_assert(&hsh6->mtx, MA_OWNED); fle6 = uma_zalloc_arg(priv->zone6, priv, M_NOWAIT); if (fle6 == NULL) { atomic_add_32(&priv->info.nfinfo_alloc_failed, 1); return (ENOMEM); } /* * Now fle is totally ours. It is detached from all lists, * we can safely edit it. */ fle6->f.version = IP6VERSION; bcopy(r, &fle6->f.r, sizeof(struct flow6_rec)); fle6->f.bytes = plen; fle6->f.packets = 1; fle6->f.tcp_flags = tcp_flags; fle6->f.first = fle6->f.last = time_uptime; /* * First we do route table lookup on destination address. So we can * fill in out_ifx, dst_mask, nexthop, and dst_as in future releases. */ if ((flags & NG_NETFLOW_CONF_NODSTLOOKUP) == 0) { bzero(&rin6, sizeof(struct route_in6)); dst = (struct sockaddr_in6 *)&rin6.ro_dst; dst->sin6_len = sizeof(struct sockaddr_in6); dst->sin6_family = AF_INET6; dst->sin6_addr = r->dst.r_dst6; rin6.ro_rt = rtalloc1_fib((struct sockaddr *)dst, 0, 0, r->fib); if (rin6.ro_rt != NULL) { rt = rin6.ro_rt; fle6->f.fle_o_ifx = rt->rt_ifp->if_index; if (rt->rt_flags & RTF_GATEWAY && rt->rt_gateway->sa_family == AF_INET6) fle6->f.n.next_hop6 = ((struct sockaddr_in6 *)(rt->rt_gateway))->sin6_addr; if (rt_mask(rt)) fle6->f.dst_mask = RT_MASK6(rt); else fle6->f.dst_mask = 128; RTFREE_LOCKED(rt); } } if ((flags & NG_NETFLOW_CONF_NODSTLOOKUP) == 0) { /* Do route lookup on source address, to fill in src_mask. */ bzero(&rin6, sizeof(struct route_in6)); src = (struct sockaddr_in6 *)&rin6.ro_dst; src->sin6_len = sizeof(struct sockaddr_in6); src->sin6_family = AF_INET6; src->sin6_addr = r->src.r_src6; rin6.ro_rt = rtalloc1_fib((struct sockaddr *)src, 0, 0, r->fib); if (rin6.ro_rt != NULL) { rt = rin6.ro_rt; if (rt_mask(rt)) fle6->f.src_mask = RT_MASK6(rt); else fle6->f.src_mask = 128; RTFREE_LOCKED(rt); } } /* Push new flow at the and of hash. */ TAILQ_INSERT_TAIL(&hsh6->head, (struct flow_entry *)fle6, fle_hash); return (0); } #undef ipv6_masklen #undef RT_MASK6 #endif /* * Non-static functions called from ng_netflow.c */ /* Allocate memory and set up flow cache */ void ng_netflow_cache_init(priv_p priv) { struct flow_hash_entry *hsh; int i; /* Initialize cache UMA zone. */ priv->zone = uma_zcreate("NetFlow IPv4 cache", sizeof(struct flow_entry), uma_ctor_flow, uma_dtor_flow, NULL, NULL, UMA_ALIGN_CACHE, 0); uma_zone_set_max(priv->zone, CACHESIZE); #ifdef INET6 priv->zone6 = uma_zcreate("NetFlow IPv6 cache", sizeof(struct flow6_entry), uma_ctor_flow6, uma_dtor_flow6, NULL, NULL, UMA_ALIGN_CACHE, 0); uma_zone_set_max(priv->zone6, CACHESIZE); #endif /* Allocate hash. */ priv->hash = malloc(NBUCKETS * sizeof(struct flow_hash_entry), M_NETFLOW_HASH, M_WAITOK | M_ZERO); /* Initialize hash. */ for (i = 0, hsh = priv->hash; i < NBUCKETS; i++, hsh++) { mtx_init(&hsh->mtx, "hash mutex", NULL, MTX_DEF); TAILQ_INIT(&hsh->head); } #ifdef INET6 /* Allocate hash. */ priv->hash6 = malloc(NBUCKETS * sizeof(struct flow_hash_entry), M_NETFLOW_HASH, M_WAITOK | M_ZERO); /* Initialize hash. */ for (i = 0, hsh = priv->hash6; i < NBUCKETS; i++, hsh++) { mtx_init(&hsh->mtx, "hash mutex", NULL, MTX_DEF); TAILQ_INIT(&hsh->head); } #endif ng_netflow_v9_cache_init(priv); CTR0(KTR_NET, "ng_netflow startup()"); } /* Initialize new FIB table for v5 and v9 */ int ng_netflow_fib_init(priv_p priv, int fib) { fib_export_p fe = priv_to_fib(priv, fib); CTR1(KTR_NET, "ng_netflow(): fib init: %d", fib); if (fe != NULL) return (0); if ((fe = malloc(sizeof(struct fib_export), M_NETGRAPH, M_NOWAIT | M_ZERO)) == NULL) return (ENOMEM); mtx_init(&fe->export_mtx, "export dgram lock", NULL, MTX_DEF); mtx_init(&fe->export9_mtx, "export9 dgram lock", NULL, MTX_DEF); fe->fib = fib; fe->domain_id = fib; if (atomic_cmpset_ptr((volatile uintptr_t *)&priv->fib_data[fib], (uintptr_t)NULL, (uintptr_t)fe) == 0) { /* FIB already set up by other ISR */ CTR3(KTR_NET, "ng_netflow(): fib init: %d setup %p but got %p", fib, fe, priv_to_fib(priv, fib)); mtx_destroy(&fe->export_mtx); mtx_destroy(&fe->export9_mtx); free(fe, M_NETGRAPH); } else { /* Increase counter for statistics */ CTR3(KTR_NET, "ng_netflow(): fib %d setup to %p (%p)", fib, fe, priv_to_fib(priv, fib)); atomic_fetchadd_32(&priv->info.nfinfo_alloc_fibs, 1); } return (0); } /* Free all flow cache memory. Called from node close method. */ void ng_netflow_cache_flush(priv_p priv) { struct flow_entry *fle, *fle1; struct flow_hash_entry *hsh; struct netflow_export_item exp; fib_export_p fe; int i; bzero(&exp, sizeof(exp)); /* * We are going to free probably billable data. * Expire everything before freeing it. * No locking is required since callout is already drained. */ for (hsh = priv->hash, i = 0; i < NBUCKETS; hsh++, i++) TAILQ_FOREACH_SAFE(fle, &hsh->head, fle_hash, fle1) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); fe = priv_to_fib(priv, fle->f.r.fib); expire_flow(priv, fe, fle, NG_QUEUE); } #ifdef INET6 for (hsh = priv->hash6, i = 0; i < NBUCKETS; hsh++, i++) TAILQ_FOREACH_SAFE(fle, &hsh->head, fle_hash, fle1) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); fe = priv_to_fib(priv, fle->f.r.fib); expire_flow(priv, fe, fle, NG_QUEUE); } #endif uma_zdestroy(priv->zone); /* Destroy hash mutexes. */ for (i = 0, hsh = priv->hash; i < NBUCKETS; i++, hsh++) mtx_destroy(&hsh->mtx); /* Free hash memory. */ if (priv->hash != NULL) free(priv->hash, M_NETFLOW_HASH); #ifdef INET6 uma_zdestroy(priv->zone6); /* Destroy hash mutexes. */ for (i = 0, hsh = priv->hash6; i < NBUCKETS; i++, hsh++) mtx_destroy(&hsh->mtx); /* Free hash memory. */ if (priv->hash6 != NULL) free(priv->hash6, M_NETFLOW_HASH); #endif for (i = 0; i < priv->maxfibs; i++) { if ((fe = priv_to_fib(priv, i)) == NULL) continue; if (fe->exp.item != NULL) export_send(priv, fe, fe->exp.item, NG_QUEUE); if (fe->exp.item9 != NULL) export9_send(priv, fe, fe->exp.item9, fe->exp.item9_opt, NG_QUEUE); mtx_destroy(&fe->export_mtx); mtx_destroy(&fe->export9_mtx); free(fe, M_NETGRAPH); } ng_netflow_v9_cache_flush(priv); } /* Insert packet from into flow cache. */ int ng_netflow_flow_add(priv_p priv, fib_export_p fe, struct ip *ip, caddr_t upper_ptr, uint8_t upper_proto, uint8_t flags, unsigned int src_if_index) { struct flow_entry *fle, *fle1; struct flow_hash_entry *hsh; struct flow_rec r; int hlen, plen; int error = 0; uint16_t eproto; uint8_t tcp_flags = 0; bzero(&r, sizeof(r)); if (ip->ip_v != IPVERSION) return (EINVAL); hlen = ip->ip_hl << 2; if (hlen < sizeof(struct ip)) return (EINVAL); eproto = ETHERTYPE_IP; /* Assume L4 template by default */ r.flow_type = NETFLOW_V9_FLOW_V4_L4; r.r_src = ip->ip_src; r.r_dst = ip->ip_dst; r.fib = fe->fib; plen = ntohs(ip->ip_len); r.r_ip_p = ip->ip_p; r.r_tos = ip->ip_tos; r.r_i_ifx = src_if_index; /* * XXX NOTE: only first fragment of fragmented TCP, UDP and * ICMP packet will be recorded with proper s_port and d_port. * Following fragments will be recorded simply as IP packet with * ip_proto = ip->ip_p and s_port, d_port set to zero. * I know, it looks like bug. But I don't want to re-implement * ip packet assebmling here. Anyway, (in)famous trafd works this way - * and nobody complains yet :) */ if ((ip->ip_off & htons(IP_OFFMASK)) == 0) switch(r.r_ip_p) { case IPPROTO_TCP: { struct tcphdr *tcp; tcp = (struct tcphdr *)((caddr_t )ip + hlen); r.r_sport = tcp->th_sport; r.r_dport = tcp->th_dport; tcp_flags = tcp->th_flags; break; } case IPPROTO_UDP: r.r_ports = *(uint32_t *)((caddr_t )ip + hlen); break; } atomic_fetchadd_32(&priv->info.nfinfo_packets, 1); /* XXX: atomic */ priv->info.nfinfo_bytes += plen; /* Find hash slot. */ hsh = &priv->hash[ip_hash(&r)]; mtx_lock(&hsh->mtx); /* * Go through hash and find our entry. If we encounter an * entry, that should be expired, purge it. We do a reverse * search since most active entries are first, and most * searches are done on most active entries. */ TAILQ_FOREACH_REVERSE_SAFE(fle, &hsh->head, fhead, fle_hash, fle1) { if (bcmp(&r, &fle->f.r, sizeof(struct flow_rec)) == 0) break; if ((INACTIVE(fle) && SMALL(fle)) || AGED(fle)) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); expire_flow(priv, priv_to_fib(priv, fle->f.r.fib), fle, NG_QUEUE); atomic_add_32(&priv->info.nfinfo_act_exp, 1); } } if (fle) { /* An existent entry. */ fle->f.bytes += plen; fle->f.packets ++; fle->f.tcp_flags |= tcp_flags; fle->f.last = time_uptime; /* * We have the following reasons to expire flow in active way: * - it hit active timeout * - a TCP connection closed * - it is going to overflow counter */ if (tcp_flags & TH_FIN || tcp_flags & TH_RST || AGED(fle) || (fle->f.bytes >= (CNTR_MAX - IF_MAXMTU)) ) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); expire_flow(priv, priv_to_fib(priv, fle->f.r.fib), fle, NG_QUEUE); atomic_add_32(&priv->info.nfinfo_act_exp, 1); } else { /* * It is the newest, move it to the tail, * if it isn't there already. Next search will * locate it quicker. */ if (fle != TAILQ_LAST(&hsh->head, fhead)) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); TAILQ_INSERT_TAIL(&hsh->head, fle, fle_hash); } } } else /* A new flow entry. */ error = hash_insert(priv, hsh, &r, plen, flags, tcp_flags); mtx_unlock(&hsh->mtx); return (error); } #ifdef INET6 /* Insert IPv6 packet from into flow cache. */ int ng_netflow_flow6_add(priv_p priv, fib_export_p fe, struct ip6_hdr *ip6, caddr_t upper_ptr, uint8_t upper_proto, uint8_t flags, unsigned int src_if_index) { struct flow_entry *fle = NULL, *fle1; struct flow6_entry *fle6; struct flow_hash_entry *hsh; struct flow6_rec r; int plen; int error = 0; uint8_t tcp_flags = 0; /* check version */ if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) return (EINVAL); bzero(&r, sizeof(r)); r.src.r_src6 = ip6->ip6_src; r.dst.r_dst6 = ip6->ip6_dst; r.fib = fe->fib; /* Assume L4 template by default */ r.flow_type = NETFLOW_V9_FLOW_V6_L4; plen = ntohs(ip6->ip6_plen) + sizeof(struct ip6_hdr); #if 0 /* XXX: set DSCP/CoS value */ r.r_tos = ip->ip_tos; #endif if ((flags & NG_NETFLOW_IS_FRAG) == 0) { switch(upper_proto) { case IPPROTO_TCP: { struct tcphdr *tcp; tcp = (struct tcphdr *)upper_ptr; r.r_ports = *(uint32_t *)upper_ptr; tcp_flags = tcp->th_flags; break; } case IPPROTO_UDP: case IPPROTO_SCTP: r.r_ports = *(uint32_t *)upper_ptr; break; } } r.r_ip_p = upper_proto; r.r_i_ifx = src_if_index; atomic_fetchadd_32(&priv->info.nfinfo_packets6, 1); /* XXX: atomic */ priv->info.nfinfo_bytes6 += plen; /* Find hash slot. */ hsh = &priv->hash6[ip6_hash(&r)]; mtx_lock(&hsh->mtx); /* * Go through hash and find our entry. If we encounter an * entry, that should be expired, purge it. We do a reverse * search since most active entries are first, and most * searches are done on most active entries. */ TAILQ_FOREACH_REVERSE_SAFE(fle, &hsh->head, fhead, fle_hash, fle1) { if (fle->f.version != IP6VERSION) continue; fle6 = (struct flow6_entry *)fle; if (bcmp(&r, &fle6->f.r, sizeof(struct flow6_rec)) == 0) break; if ((INACTIVE(fle6) && SMALL(fle6)) || AGED(fle6)) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); expire_flow(priv, priv_to_fib(priv, fle->f.r.fib), fle, NG_QUEUE); atomic_add_32(&priv->info.nfinfo_act_exp, 1); } } if (fle != NULL) { /* An existent entry. */ fle6 = (struct flow6_entry *)fle; fle6->f.bytes += plen; fle6->f.packets ++; fle6->f.tcp_flags |= tcp_flags; fle6->f.last = time_uptime; /* * We have the following reasons to expire flow in active way: * - it hit active timeout * - a TCP connection closed * - it is going to overflow counter */ if (tcp_flags & TH_FIN || tcp_flags & TH_RST || AGED(fle6) || (fle6->f.bytes >= (CNTR_MAX - IF_MAXMTU)) ) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); expire_flow(priv, priv_to_fib(priv, fle->f.r.fib), fle, NG_QUEUE); atomic_add_32(&priv->info.nfinfo_act_exp, 1); } else { /* * It is the newest, move it to the tail, * if it isn't there already. Next search will * locate it quicker. */ if (fle != TAILQ_LAST(&hsh->head, fhead)) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); TAILQ_INSERT_TAIL(&hsh->head, fle, fle_hash); } } } else /* A new flow entry. */ error = hash6_insert(priv, hsh, &r, plen, flags, tcp_flags); mtx_unlock(&hsh->mtx); return (error); } #endif /* * Return records from cache to userland. * * TODO: matching particular IP should be done in kernel, here. */ int ng_netflow_flow_show(priv_p priv, struct ngnf_show_header *req, struct ngnf_show_header *resp) { struct flow_hash_entry *hsh; struct flow_entry *fle; struct flow_entry_data *data = (struct flow_entry_data *)(resp + 1); #ifdef INET6 struct flow6_entry_data *data6 = (struct flow6_entry_data *)(resp + 1); #endif int i, max; i = req->hash_id; if (i > NBUCKETS-1) return (EINVAL); #ifdef INET6 if (req->version == 6) { resp->version = 6; hsh = priv->hash6 + i; max = NREC6_AT_ONCE; } else #endif if (req->version == 4) { resp->version = 4; hsh = priv->hash + i; max = NREC_AT_ONCE; } else return (EINVAL); /* * We will transfer not more than NREC_AT_ONCE. More data * will come in next message. * We send current hash index and current record number in list * to userland, and userland should return it back to us. * Then, we will restart with new entry. * * The resulting cache snapshot can be inaccurate if flow expiration * is taking place on hash item between userland data requests for * this hash item id. */ resp->nentries = 0; for (; i < NBUCKETS; hsh++, i++) { int list_id; if (mtx_trylock(&hsh->mtx) == 0) { /* * Requested hash index is not available, * relay decision to skip or re-request data * to userland. */ resp->hash_id = i; resp->list_id = 0; return (0); } list_id = 0; TAILQ_FOREACH(fle, &hsh->head, fle_hash) { if (hsh->mtx.mtx_lock & MTX_CONTESTED) { resp->hash_id = i; resp->list_id = list_id; mtx_unlock(&hsh->mtx); return (0); } list_id++; /* Search for particular record in list. */ if (req->list_id > 0) { if (list_id < req->list_id) continue; /* Requested list position found. */ req->list_id = 0; } #ifdef INET6 if (req->version == 6) { struct flow6_entry *fle6; fle6 = (struct flow6_entry *)fle; bcopy(&fle6->f, data6 + resp->nentries, sizeof(fle6->f)); } else #endif bcopy(&fle->f, data + resp->nentries, sizeof(fle->f)); resp->nentries++; if (resp->nentries == max) { resp->hash_id = i; /* * If it was the last item in list * we simply skip to next hash_id. */ resp->list_id = list_id + 1; mtx_unlock(&hsh->mtx); return (0); } } mtx_unlock(&hsh->mtx); } resp->hash_id = resp->list_id = 0; return (0); } /* We have full datagram in privdata. Send it to export hook. */ static int export_send(priv_p priv, fib_export_p fe, item_p item, int flags) { struct mbuf *m = NGI_M(item); struct netflow_v5_export_dgram *dgram = mtod(m, struct netflow_v5_export_dgram *); struct netflow_v5_header *header = &dgram->header; struct timespec ts; int error = 0; /* Fill mbuf header. */ m->m_len = m->m_pkthdr.len = sizeof(struct netflow_v5_record) * header->count + sizeof(struct netflow_v5_header); /* Fill export header. */ header->sys_uptime = htonl(MILLIUPTIME(time_uptime)); getnanotime(&ts); header->unix_secs = htonl(ts.tv_sec); header->unix_nsecs = htonl(ts.tv_nsec); header->engine_type = 0; header->engine_id = fe->domain_id; header->pad = 0; header->flow_seq = htonl(atomic_fetchadd_32(&fe->flow_seq, header->count)); header->count = htons(header->count); if (priv->export != NULL) NG_FWD_ITEM_HOOK_FLAGS(error, item, priv->export, flags); else NG_FREE_ITEM(item); return (error); } /* Add export record to dgram. */ static int export_add(item_p item, struct flow_entry *fle) { struct netflow_v5_export_dgram *dgram = mtod(NGI_M(item), struct netflow_v5_export_dgram *); struct netflow_v5_header *header = &dgram->header; struct netflow_v5_record *rec; rec = &dgram->r[header->count]; header->count ++; KASSERT(header->count <= NETFLOW_V5_MAX_RECORDS, ("ng_netflow: export too big")); /* Fill in export record. */ rec->src_addr = fle->f.r.r_src.s_addr; rec->dst_addr = fle->f.r.r_dst.s_addr; rec->next_hop = fle->f.next_hop.s_addr; rec->i_ifx = htons(fle->f.fle_i_ifx); rec->o_ifx = htons(fle->f.fle_o_ifx); rec->packets = htonl(fle->f.packets); rec->octets = htonl(fle->f.bytes); rec->first = htonl(MILLIUPTIME(fle->f.first)); rec->last = htonl(MILLIUPTIME(fle->f.last)); rec->s_port = fle->f.r.r_sport; rec->d_port = fle->f.r.r_dport; rec->flags = fle->f.tcp_flags; rec->prot = fle->f.r.r_ip_p; rec->tos = fle->f.r.r_tos; rec->dst_mask = fle->f.dst_mask; rec->src_mask = fle->f.src_mask; rec->pad1 = 0; rec->pad2 = 0; /* Not supported fields. */ rec->src_as = rec->dst_as = 0; if (header->count == NETFLOW_V5_MAX_RECORDS) return (1); /* end of datagram */ else return (0); } /* Periodic flow expiry run. */ void ng_netflow_expire(void *arg) { struct flow_entry *fle, *fle1; struct flow_hash_entry *hsh; priv_p priv = (priv_p )arg; uint32_t used; int i; /* * Going through all the cache. */ for (hsh = priv->hash, i = 0; i < NBUCKETS; hsh++, i++) { /* * Skip entries, that are already being worked on. */ if (mtx_trylock(&hsh->mtx) == 0) continue; used = atomic_load_acq_32(&priv->info.nfinfo_used); TAILQ_FOREACH_SAFE(fle, &hsh->head, fle_hash, fle1) { /* * Interrupt thread wants this entry! * Quick! Quick! Bail out! */ if (hsh->mtx.mtx_lock & MTX_CONTESTED) break; /* * Don't expire aggressively while hash collision * ratio is predicted small. */ if (used <= (NBUCKETS*2) && !INACTIVE(fle)) break; if ((INACTIVE(fle) && (SMALL(fle) || (used > (NBUCKETS*2)))) || AGED(fle)) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); expire_flow(priv, priv_to_fib(priv, fle->f.r.fib), fle, NG_NOFLAGS); used--; atomic_add_32(&priv->info.nfinfo_inact_exp, 1); } } mtx_unlock(&hsh->mtx); } #ifdef INET6 for (hsh = priv->hash6, i = 0; i < NBUCKETS; hsh++, i++) { struct flow6_entry *fle6; /* * Skip entries, that are already being worked on. */ if (mtx_trylock(&hsh->mtx) == 0) continue; used = atomic_load_acq_32(&priv->info.nfinfo_used6); TAILQ_FOREACH_SAFE(fle, &hsh->head, fle_hash, fle1) { fle6 = (struct flow6_entry *)fle; /* * Interrupt thread wants this entry! * Quick! Quick! Bail out! */ if (hsh->mtx.mtx_lock & MTX_CONTESTED) break; /* * Don't expire aggressively while hash collision * ratio is predicted small. */ if (used <= (NBUCKETS*2) && !INACTIVE(fle6)) break; if ((INACTIVE(fle6) && (SMALL(fle6) || (used > (NBUCKETS*2)))) || AGED(fle6)) { TAILQ_REMOVE(&hsh->head, fle, fle_hash); expire_flow(priv, priv_to_fib(priv, fle->f.r.fib), fle, NG_NOFLAGS); used--; atomic_add_32(&priv->info.nfinfo_inact_exp, 1); } } mtx_unlock(&hsh->mtx); } #endif /* Schedule next expire. */ callout_reset(&priv->exp_callout, (1*hz), &ng_netflow_expire, (void *)priv); }