/*- * Copyright (c) 2016-2018 Netflix, Inc. * Copyright (c) 2016-2021 Mellanox Technologies. * * 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 REGENTS 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 REGENTS 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. * */ #include #include "opt_inet.h" #include "opt_inet6.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 #include #include #include #include #include #include #include #include #ifdef TCP_BLACKBOX #include #endif static void build_ack_entry(struct tcp_ackent *ae, struct tcphdr *th, struct mbuf *m, uint32_t *ts_ptr, uint16_t iptos) { /* * Given a TCP ACK, summarize it down into the small TCP ACK * entry. */ ae->timestamp = m->m_pkthdr.rcv_tstmp; ae->flags = 0; if (m->m_flags & M_TSTMP_LRO) ae->flags |= TSTMP_LRO; else if (m->m_flags & M_TSTMP) ae->flags |= TSTMP_HDWR; ae->seq = th->th_seq; ae->ack = th->th_ack; ae->flags |= tcp_get_flags(th); if (ts_ptr != NULL) { ae->ts_value = ntohl(ts_ptr[1]); ae->ts_echo = ntohl(ts_ptr[2]); ae->flags |= HAS_TSTMP; } ae->win = th->th_win; ae->codepoint = iptos; } static inline bool tcp_lro_ack_valid(struct mbuf *m, struct tcphdr *th, uint32_t **ppts, bool *other_opts) { /* * This function returns two bits of valuable information. * a) Is what is present capable of being ack-compressed, * we can ack-compress if there is no options or just * a timestamp option, and of course the th_flags must * be correct as well. * b) Our other options present such as SACK. This is * used to determine if we want to wakeup or not. */ bool ret = true; switch (th->th_off << 2) { case (sizeof(*th) + TCPOLEN_TSTAMP_APPA): *ppts = (uint32_t *)(th + 1); /* Check if we have only one timestamp option. */ if (**ppts == TCP_LRO_TS_OPTION) *other_opts = false; else { *other_opts = true; ret = false; } break; case (sizeof(*th)): /* No options. */ *ppts = NULL; *other_opts = false; break; default: *ppts = NULL; *other_opts = true; ret = false; break; } /* For ACKCMP we only accept ACK, PUSH, ECE and CWR. */ if ((tcp_get_flags(th) & ~(TH_ACK | TH_PUSH | TH_ECE | TH_CWR)) != 0) ret = false; /* If it has data on it we cannot compress it */ if (m->m_pkthdr.lro_tcp_d_len) ret = false; /* ACK flag must be set. */ if (!(tcp_get_flags(th) & TH_ACK)) ret = false; return (ret); } static bool tcp_lro_check_wake_status(struct tcpcb *tp) { if (tp->t_fb->tfb_early_wake_check != NULL) return ((tp->t_fb->tfb_early_wake_check)(tp)); return (false); } #ifdef TCP_BLACKBOX static void tcp_lro_log(struct tcpcb *tp, const struct lro_ctrl *lc, const struct lro_entry *le, const struct mbuf *m, int frm, int32_t tcp_data_len, uint32_t th_seq, uint32_t th_ack, uint16_t th_win) { if (tcp_bblogging_on(tp)) { union tcp_log_stackspecific log; struct timeval tv, btv; uint32_t cts; cts = tcp_get_usecs(&tv); memset(&log, 0, sizeof(union tcp_log_stackspecific)); log.u_bbr.flex8 = frm; log.u_bbr.flex1 = tcp_data_len; if (m) log.u_bbr.flex2 = m->m_pkthdr.len; else log.u_bbr.flex2 = 0; if (le->m_head) { log.u_bbr.flex3 = le->m_head->m_pkthdr.lro_nsegs; log.u_bbr.flex4 = le->m_head->m_pkthdr.lro_tcp_d_len; log.u_bbr.flex5 = le->m_head->m_pkthdr.len; log.u_bbr.delRate = le->m_head->m_flags; log.u_bbr.rttProp = le->m_head->m_pkthdr.rcv_tstmp; } log.u_bbr.inflight = th_seq; log.u_bbr.delivered = th_ack; log.u_bbr.timeStamp = cts; log.u_bbr.epoch = le->next_seq; log.u_bbr.lt_epoch = le->ack_seq; log.u_bbr.pacing_gain = th_win; log.u_bbr.cwnd_gain = le->window; log.u_bbr.lost = curcpu; log.u_bbr.cur_del_rate = (uintptr_t)m; log.u_bbr.bw_inuse = (uintptr_t)le->m_head; bintime2timeval(&lc->lro_last_queue_time, &btv); log.u_bbr.flex6 = tcp_tv_to_usectick(&btv); log.u_bbr.flex7 = le->compressed; log.u_bbr.pacing_gain = le->uncompressed; if (in_epoch(net_epoch_preempt)) log.u_bbr.inhpts = 1; else log.u_bbr.inhpts = 0; TCP_LOG_EVENTP(tp, NULL, &tptosocket(tp)->so_rcv, &tptosocket(tp)->so_snd, TCP_LOG_LRO, 0, 0, &log, false, &tv); } } #endif static struct mbuf * tcp_lro_get_last_if_ackcmp(struct lro_ctrl *lc, struct lro_entry *le, struct tcpcb *tp, int32_t *new_m, bool can_append_old_cmp) { struct mbuf *m; /* Look at the last mbuf if any in queue */ if (can_append_old_cmp) { m = STAILQ_LAST(&tp->t_inqueue, mbuf, m_stailqpkt); if (m != NULL && (m->m_flags & M_ACKCMP) != 0) { if (M_TRAILINGSPACE(m) >= sizeof(struct tcp_ackent)) { #ifdef TCP_BLACKBOX tcp_lro_log(tp, lc, le, NULL, 23, 0, 0, 0, 0); #endif *new_m = 0; counter_u64_add(tcp_extra_mbuf, 1); return (m); } else { /* Mark we ran out of space */ tp->t_flags2 |= TF2_MBUF_L_ACKS; } } } /* Decide mbuf size. */ #ifdef TCP_BLACKBOX tcp_lro_log(tp, lc, le, NULL, 21, 0, 0, 0, 0); #endif if (tp->t_flags2 & TF2_MBUF_L_ACKS) m = m_getcl(M_NOWAIT, MT_DATA, M_ACKCMP | M_PKTHDR); else m = m_gethdr(M_NOWAIT, MT_DATA); if (__predict_false(m == NULL)) { counter_u64_add(tcp_would_have_but, 1); return (NULL); } counter_u64_add(tcp_comp_total, 1); m->m_pkthdr.rcvif = lc->ifp; m->m_flags |= M_ACKCMP; *new_m = 1; return (m); } /* * Do BPF tap for either ACK_CMP packets or MBUF QUEUE type packets * and strip all, but the IPv4/IPv6 header. */ static bool do_bpf_strip_and_compress(struct tcpcb *tp, struct lro_ctrl *lc, struct lro_entry *le, struct mbuf **pp, struct mbuf **cmp, struct mbuf **mv_to, bool *should_wake, bool bpf_req, bool lagg_bpf_req, struct ifnet *lagg_ifp, bool can_append_old_cmp) { union { void *ptr; struct ip *ip4; struct ip6_hdr *ip6; } l3; struct mbuf *m; struct mbuf *nm; struct tcphdr *th; struct tcp_ackent *ack_ent; uint32_t *ts_ptr; int32_t n_mbuf; bool other_opts, can_compress; uint8_t lro_type; uint16_t iptos; int tcp_hdr_offset; int idx; /* Get current mbuf. */ m = *pp; /* Let the BPF see the packet */ if (__predict_false(bpf_req)) ETHER_BPF_MTAP(lc->ifp, m); if (__predict_false(lagg_bpf_req)) ETHER_BPF_MTAP(lagg_ifp, m); tcp_hdr_offset = m->m_pkthdr.lro_tcp_h_off; lro_type = le->inner.data.lro_type; switch (lro_type) { case LRO_TYPE_NONE: lro_type = le->outer.data.lro_type; switch (lro_type) { case LRO_TYPE_IPV4_TCP: tcp_hdr_offset -= sizeof(*le->outer.ip4); m->m_pkthdr.lro_etype = ETHERTYPE_IP; IP_PROBE(receive, NULL, NULL, le->outer.ip4, lc->ifp, le->outer.ip4, NULL); break; case LRO_TYPE_IPV6_TCP: tcp_hdr_offset -= sizeof(*le->outer.ip6); m->m_pkthdr.lro_etype = ETHERTYPE_IPV6; IP_PROBE(receive, NULL, NULL, le->outer.ip6, lc->ifp, NULL, le->outer.ip6); break; default: goto compressed; } break; case LRO_TYPE_IPV4_TCP: switch (le->outer.data.lro_type) { case LRO_TYPE_IPV4_UDP: IP_PROBE(receive, NULL, NULL, le->outer.ip4, lc->ifp, le->outer.ip4, NULL); UDP_PROBE(receive, NULL, NULL, le->outer.ip4, NULL, le->outer.udp); break; case LRO_TYPE_IPV6_UDP: IP_PROBE(receive, NULL, NULL, le->outer.ip6, lc->ifp, NULL, le->outer.ip6); UDP_PROBE(receive, NULL, NULL, le->outer.ip6, NULL, le->outer.udp); break; default: __assert_unreachable(); break; } tcp_hdr_offset -= sizeof(*le->outer.ip4); m->m_pkthdr.lro_etype = ETHERTYPE_IP; IP_PROBE(receive, NULL, NULL, le->inner.ip4, NULL, le->inner.ip4, NULL); break; case LRO_TYPE_IPV6_TCP: switch (le->outer.data.lro_type) { case LRO_TYPE_IPV4_UDP: IP_PROBE(receive, NULL, NULL, le->outer.ip4, lc->ifp, le->outer.ip4, NULL); UDP_PROBE(receive, NULL, NULL, le->outer.ip4, NULL, le->outer.udp); break; case LRO_TYPE_IPV6_UDP: IP_PROBE(receive, NULL, NULL, le->outer.ip6, lc->ifp, NULL, le->outer.ip6); UDP_PROBE(receive, NULL, NULL, le->outer.ip6, NULL, le->outer.udp); break; default: __assert_unreachable(); break; } tcp_hdr_offset -= sizeof(*le->outer.ip6); m->m_pkthdr.lro_etype = ETHERTYPE_IPV6; IP_PROBE(receive, NULL, NULL, le->inner.ip6, NULL, NULL, le->inner.ip6); break; default: goto compressed; } MPASS(tcp_hdr_offset >= 0); m_adj(m, tcp_hdr_offset); m->m_flags |= M_LRO_EHDRSTRP; m->m_flags &= ~M_ACKCMP; m->m_pkthdr.lro_tcp_h_off -= tcp_hdr_offset; th = tcp_lro_get_th(m); th->th_sum = 0; /* TCP checksum is valid. */ tcp_fields_to_host(th); TCP_PROBE5(receive, NULL, tp, m, tp, th); /* Check if ACK can be compressed */ can_compress = tcp_lro_ack_valid(m, th, &ts_ptr, &other_opts); /* Now lets look at the should wake states */ if ((other_opts == true) && ((tp->t_flags2 & TF2_DONT_SACK_QUEUE) == 0)) { /* * If there are other options (SACK?) and the * tcp endpoint has not expressly told us it does * not care about SACKS, then we should wake up. */ *should_wake = true; } else if (*should_wake == false) { /* Wakeup override check if we are false here */ *should_wake = tcp_lro_check_wake_status(tp); } /* Is the ack compressable? */ if (can_compress == false) goto done; /* Does the TCP endpoint support ACK compression? */ if ((tp->t_flags2 & TF2_MBUF_ACKCMP) == 0) goto done; /* Lets get the TOS/traffic class field */ l3.ptr = mtod(m, void *); switch (lro_type) { case LRO_TYPE_IPV4_TCP: iptos = l3.ip4->ip_tos; break; case LRO_TYPE_IPV6_TCP: iptos = IPV6_TRAFFIC_CLASS(l3.ip6); break; default: iptos = 0; /* Keep compiler happy. */ break; } /* Now lets get space if we don't have some already */ if (*cmp == NULL) { new_one: nm = tcp_lro_get_last_if_ackcmp(lc, le, tp, &n_mbuf, can_append_old_cmp); if (__predict_false(nm == NULL)) goto done; *cmp = nm; if (n_mbuf) { /* * Link in the new cmp ack to our in-order place, * first set our cmp ack's next to where we are. */ nm->m_nextpkt = m; (*pp) = nm; /* * Set it up so mv_to is advanced to our * compressed ack. This way the caller can * advance pp to the right place. */ *mv_to = nm; /* * Advance it here locally as well. */ pp = &nm->m_nextpkt; } } else { /* We have one already we are working on */ nm = *cmp; if (M_TRAILINGSPACE(nm) < sizeof(struct tcp_ackent)) { /* We ran out of space */ tp->t_flags2 |= TF2_MBUF_L_ACKS; goto new_one; } } MPASS(M_TRAILINGSPACE(nm) >= sizeof(struct tcp_ackent)); counter_u64_add(tcp_inp_lro_compressed, 1); le->compressed++; /* We can add in to the one on the tail */ ack_ent = mtod(nm, struct tcp_ackent *); idx = (nm->m_len / sizeof(struct tcp_ackent)); build_ack_entry(&ack_ent[idx], th, m, ts_ptr, iptos); /* Bump the size of both pkt-hdr and len */ nm->m_len += sizeof(struct tcp_ackent); nm->m_pkthdr.len += sizeof(struct tcp_ackent); compressed: /* Advance to next mbuf before freeing. */ *pp = m->m_nextpkt; m->m_nextpkt = NULL; m_freem(m); return (true); done: counter_u64_add(tcp_uncomp_total, 1); le->uncompressed++; return (false); } static void tcp_queue_pkts(struct tcpcb *tp, struct lro_entry *le) { INP_WLOCK_ASSERT(tptoinpcb(tp)); STAILQ_HEAD(, mbuf) q = { le->m_head, &STAILQ_NEXT(le->m_last_mbuf, m_stailqpkt) }; STAILQ_CONCAT(&tp->t_inqueue, &q); le->m_head = NULL; le->m_last_mbuf = NULL; } static struct tcpcb * tcp_lro_lookup(struct ifnet *ifp, struct lro_parser *pa) { struct inpcb *inp; CURVNET_ASSERT_SET(); switch (pa->data.lro_type) { #ifdef INET6 case LRO_TYPE_IPV6_TCP: inp = in6_pcblookup(&V_tcbinfo, &pa->data.s_addr.v6, pa->data.s_port, &pa->data.d_addr.v6, pa->data.d_port, INPLOOKUP_WLOCKPCB, ifp); break; #endif #ifdef INET case LRO_TYPE_IPV4_TCP: inp = in_pcblookup(&V_tcbinfo, pa->data.s_addr.v4, pa->data.s_port, pa->data.d_addr.v4, pa->data.d_port, INPLOOKUP_WLOCKPCB, ifp); break; #endif default: return (NULL); } return (intotcpcb(inp)); } static int _tcp_lro_flush_tcphpts(struct lro_ctrl *lc, struct lro_entry *le) { struct tcpcb *tp; struct mbuf **pp, *cmp, *mv_to; struct ifnet *lagg_ifp; bool bpf_req, lagg_bpf_req, should_wake, can_append_old_cmp; /* Check if packet doesn't belongs to our network interface. */ if ((tcplro_stacks_wanting_mbufq == 0) || (le->outer.data.vlan_id != 0) || (le->inner.data.lro_type != LRO_TYPE_NONE)) return (TCP_LRO_CANNOT); #ifdef INET6 /* * Be proactive about unspecified IPv6 address in source. As * we use all-zero to indicate unbounded/unconnected pcb, * unspecified IPv6 address can be used to confuse us. * * Note that packets with unspecified IPv6 destination is * already dropped in ip6_input. */ if (__predict_false(le->outer.data.lro_type == LRO_TYPE_IPV6_TCP && IN6_IS_ADDR_UNSPECIFIED(&le->outer.data.s_addr.v6))) return (TCP_LRO_CANNOT); if (__predict_false(le->inner.data.lro_type == LRO_TYPE_IPV6_TCP && IN6_IS_ADDR_UNSPECIFIED(&le->inner.data.s_addr.v6))) return (TCP_LRO_CANNOT); #endif CURVNET_SET(lc->ifp->if_vnet); /* * Ensure that there are no packet filter hooks which would normally * being triggered in ether_demux(), ip_input(), or ip6_input(). */ if ( #ifdef INET PFIL_HOOKED_IN(V_inet_pfil_head) || #endif #ifdef INET6 PFIL_HOOKED_IN(V_inet6_pfil_head) || #endif PFIL_HOOKED_IN(V_link_pfil_head)) { CURVNET_RESTORE(); return (TCP_LRO_CANNOT); } /* Lookup inp, if any. Returns locked TCP inpcb. */ tp = tcp_lro_lookup(lc->ifp, (le->inner.data.lro_type == LRO_TYPE_NONE) ? &le->outer : &le->inner); CURVNET_RESTORE(); if (tp == NULL) return (TCP_LRO_CANNOT); counter_u64_add(tcp_inp_lro_locks_taken, 1); /* Check if the inp is dead, Jim. */ if (tp->t_state == TCPS_TIME_WAIT) { INP_WUNLOCK(tptoinpcb(tp)); return (TCP_LRO_CANNOT); } if (tp->t_lro_cpu == HPTS_CPU_NONE && lc->lro_cpu_is_set == 1) tp->t_lro_cpu = lc->lro_last_cpu; /* Check if the transport doesn't support the needed optimizations. */ if ((tp->t_flags2 & (TF2_SUPPORTS_MBUFQ | TF2_MBUF_ACKCMP)) == 0) { INP_WUNLOCK(tptoinpcb(tp)); return (TCP_LRO_CANNOT); } if (tp->t_flags2 & TF2_MBUF_QUEUE_READY) should_wake = false; else should_wake = true; /* Check if packets should be tapped to BPF. */ bpf_req = bpf_peers_present(lc->ifp->if_bpf); lagg_bpf_req = false; lagg_ifp = NULL; if (lc->ifp->if_type == IFT_IEEE8023ADLAG || lc->ifp->if_type == IFT_INFINIBANDLAG) { struct lagg_port *lp = lc->ifp->if_lagg; struct lagg_softc *sc = lp->lp_softc; lagg_ifp = sc->sc_ifp; if (lagg_ifp != NULL) lagg_bpf_req = bpf_peers_present(lagg_ifp->if_bpf); } /* Strip and compress all the incoming packets. */ can_append_old_cmp = true; cmp = NULL; for (pp = &le->m_head; *pp != NULL; ) { mv_to = NULL; if (do_bpf_strip_and_compress(tp, lc, le, pp, &cmp, &mv_to, &should_wake, bpf_req, lagg_bpf_req, lagg_ifp, can_append_old_cmp) == false) { /* Advance to next mbuf. */ pp = &(*pp)->m_nextpkt; /* * Once we have appended we can't look in the pending * inbound packets for a compressed ack to append to. */ can_append_old_cmp = false; /* * Once we append we also need to stop adding to any * compressed ack we were remembering. A new cmp * ack will be required. */ cmp = NULL; #ifdef TCP_BLACKBOX tcp_lro_log(tp, lc, le, NULL, 25, 0, 0, 0, 0); #endif } else if (mv_to != NULL) { /* We are asked to move pp up */ pp = &mv_to->m_nextpkt; #ifdef TCP_BLACKBOX tcp_lro_log(tp, lc, le, NULL, 24, 0, 0, 0, 0); } else tcp_lro_log(tp, lc, le, NULL, 26, 0, 0, 0, 0); #else } #endif } /* Update "m_last_mbuf", if any. */ if (pp == &le->m_head) le->m_last_mbuf = *pp; else le->m_last_mbuf = __containerof(pp, struct mbuf, m_nextpkt); /* Check if any data mbufs left. */ if (le->m_head != NULL) { counter_u64_add(tcp_inp_lro_direct_queue, 1); #ifdef TCP_BLACKBOX tcp_lro_log(tp, lc, le, NULL, 22, 1, tp->t_flags2, 0, 1); #endif tcp_queue_pkts(tp, le); } if (should_wake) { /* Wakeup */ counter_u64_add(tcp_inp_lro_wokeup_queue, 1); if ((*tp->t_fb->tfb_do_queued_segments)(tp, 0)) /* TCP cb gone and unlocked. */ return (0); } INP_WUNLOCK(tptoinpcb(tp)); return (0); /* Success. */ } void tcp_lro_hpts_init(void) { tcp_lro_flush_tcphpts = _tcp_lro_flush_tcphpts; } void tcp_lro_hpts_uninit(void) { atomic_store_ptr(&tcp_lro_flush_tcphpts, NULL); }