/* * Copyright (c) 2018 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /** * @file * @brief NAT44 endpoint-dependent outside to inside network translation */ #include #include #include #include #include #include #include #include #include #include static char *nat_out2in_ed_error_strings[] = { #define _(sym,string) string, foreach_nat_out2in_ed_error #undef _ }; typedef enum { NAT_ED_SP_REASON_NO_REASON, NAT_ED_SP_REASON_LOOKUP_FAILED, NAT_ED_SP_REASON_VRF_EXPIRED, NAT_ED_SP_SESS_EXPIRED, } nat_slow_path_reason_e; typedef struct { u32 sw_if_index; u32 next_index; u32 session_index; nat_translation_error_e translation_error; nat_6t_flow_t i2of; nat_6t_flow_t o2if; clib_bihash_kv_16_8_t search_key; u8 is_slow_path; u8 translation_via_i2of; u8 lookup_skipped; u8 tcp_state; nat_slow_path_reason_e slow_path_reason; } nat44_ed_out2in_trace_t; static u8 * format_slow_path_reason (u8 *s, va_list *args) { nat_slow_path_reason_e reason = va_arg (*args, nat_slow_path_reason_e); switch (reason) { case NAT_ED_SP_REASON_NO_REASON: return format (s, "no reason for slow path"); case NAT_ED_SP_REASON_LOOKUP_FAILED: return format (s, "slow path because lookup failed"); case NAT_ED_SP_REASON_VRF_EXPIRED: return format (s, "slow path because vrf expired"); case NAT_ED_SP_SESS_EXPIRED: return format (s, "slow path because session expired"); } return format (s, "invalid reason value"); } static u8 * format_nat44_ed_out2in_trace (u8 * s, va_list * args) { CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); nat44_ed_out2in_trace_t *t = va_arg (*args, nat44_ed_out2in_trace_t *); char *tag; tag = t->is_slow_path ? "NAT44_OUT2IN_ED_SLOW_PATH" : "NAT44_OUT2IN_ED_FAST_PATH"; s = format (s, "%s: sw_if_index %d, next index %d", tag, t->sw_if_index, t->next_index); if (~0 != t->session_index) { s = format (s, ", session %d, translation result '%U' via %s", t->session_index, format_nat_ed_translation_error, t->translation_error, t->translation_via_i2of ? "i2of" : "o2if"); s = format (s, "\n i2of %U", format_nat_6t_flow, &t->i2of); s = format (s, "\n o2if %U", format_nat_6t_flow, &t->o2if); } if (!t->is_slow_path) { if (t->lookup_skipped) { s = format (s, "\n lookup skipped - cached session index used"); } else { s = format (s, "\n search key %U", format_ed_session_kvp, &t->search_key); } s = format (s, "\n %U", format_slow_path_reason, t->slow_path_reason); } if (IP_PROTOCOL_TCP == t->i2of.match.proto) { s = format (s, "\n TCP state: %U", format_nat44_ed_tcp_state, t->tcp_state); } return s; } static int next_src_nat (snat_main_t *sm, ip4_header_t *ip, u16 src_port, u16 dst_port, u32 rx_fib_index) { clib_bihash_kv_16_8_t kv, value; init_ed_k (&kv, ip->src_address.as_u32, src_port, ip->dst_address.as_u32, dst_port, rx_fib_index, ip->protocol); if (!clib_bihash_search_16_8 (&sm->flow_hash, &kv, &value)) return 1; return 0; } static void create_bypass_for_fwd (snat_main_t *sm, vlib_buffer_t *b, snat_session_t *s, ip4_header_t *ip, u32 rx_fib_index, u32 thread_index); static snat_session_t *create_session_for_static_mapping_ed ( snat_main_t *sm, vlib_buffer_t *b, ip4_address_t i2o_addr, u16 i2o_port, u32 i2o_fib_index, ip4_address_t o2i_addr, u16 o2i_port, u32 o2i_fib_index, ip_protocol_t proto, vlib_node_runtime_t *node, u32 thread_index, twice_nat_type_t twice_nat, lb_nat_type_t lb_nat, f64 now, snat_static_mapping_t *mapping); static inline u32 icmp_out2in_ed_slow_path (snat_main_t *sm, vlib_buffer_t *b, ip4_header_t *ip, icmp46_header_t *icmp, u32 sw_if_index, u32 rx_fib_index, vlib_node_runtime_t *node, u32 next, f64 now, u32 thread_index, snat_session_t **s_p) { vlib_main_t *vm = vlib_get_main (); ip_csum_t sum; u16 checksum; snat_session_t *s = 0; u8 is_addr_only, identity_nat; ip4_address_t sm_addr; u16 sm_port; u32 sm_fib_index; snat_static_mapping_t *m; u8 lookup_protocol; ip4_address_t lookup_saddr, lookup_daddr; u16 lookup_sport, lookup_dport; sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX]; rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index); if (nat_get_icmp_session_lookup_values (b, ip, &lookup_saddr, &lookup_sport, &lookup_daddr, &lookup_dport, &lookup_protocol)) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_UNSUPPORTED_PROTOCOL]; next = NAT_NEXT_DROP; goto out; } if (snat_static_mapping_match (vm, ip->dst_address, lookup_sport, rx_fib_index, ip->protocol, &sm_addr, &sm_port, &sm_fib_index, 1, &is_addr_only, 0, 0, 0, &identity_nat, &m)) { // static mapping not matched if (!sm->forwarding_enabled) { /* Don't NAT packet aimed at the intfc address */ if (!is_interface_addr (sm, node, sw_if_index, ip->dst_address.as_u32)) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION]; next = NAT_NEXT_DROP; } } else { if (next_src_nat (sm, ip, lookup_sport, lookup_dport, rx_fib_index)) { next = NAT_NEXT_IN2OUT_ED_FAST_PATH; } else { create_bypass_for_fwd (sm, b, s, ip, rx_fib_index, thread_index); } } goto out; } if (PREDICT_FALSE (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags != ICMP4_echo_reply && (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags != ICMP4_echo_request || !is_addr_only))) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE]; next = NAT_NEXT_DROP; goto out; } if (PREDICT_FALSE (identity_nat)) { goto out; } /* Create session initiated by host from external network */ s = create_session_for_static_mapping_ed ( sm, b, sm_addr, sm_port, sm_fib_index, ip->dst_address, lookup_sport, rx_fib_index, lookup_protocol, node, thread_index, 0, 0, vlib_time_now (vm), m); if (!s) next = NAT_NEXT_DROP; if (PREDICT_TRUE (!ip4_is_fragment (ip))) { sum = ip_incremental_checksum_buffer ( vm, b, (u8 *) icmp - (u8 *) vlib_buffer_get_current (b), ntohs (ip->length) - ip4_header_bytes (ip), 0); checksum = ~ip_csum_fold (sum); if (checksum != 0 && checksum != 0xffff) { next = NAT_NEXT_DROP; goto out; } } if (PREDICT_TRUE (next != NAT_NEXT_DROP && s)) { /* Accounting */ nat44_session_update_counters ( s, now, vlib_buffer_length_in_chain (vm, b), thread_index); /* Per-user LRU list maintenance */ nat44_session_update_lru (sm, s, thread_index); } out: if (NAT_NEXT_DROP == next && s) { nat_ed_session_delete (sm, s, thread_index, 1); s = 0; } *s_p = s; return next; } static_always_inline int nat44_ed_alloc_i2o_port (snat_main_t *sm, snat_address_t *a, snat_session_t *s, ip4_address_t i2o_addr, u16 i2o_port, u32 i2o_fib_index, ip_protocol_t proto, u32 thread_index, u32 snat_thread_index, ip4_address_t *outside_addr, u16 *outside_port) { u32 portnum; for (int i = 0; i < ED_PORT_ALLOC_ATTEMPTS; ++i) { portnum = (sm->port_per_thread * snat_thread_index) + snat_random_port (0, sm->port_per_thread - 1) + ED_USER_PORT_OFFSET; portnum = clib_host_to_net_u16 (portnum); nat_6t_i2o_flow_init (sm, thread_index, s, i2o_addr, i2o_port, a->addr, portnum, i2o_fib_index, proto); if (!nat_ed_ses_i2o_flow_hash_add_del (sm, thread_index, s, 1 /* is_add */)) { *outside_addr = a->addr; *outside_port = portnum; return 0; } } /* Totally out of translations to use... */ nat_ipfix_logging_addresses_exhausted (thread_index, 0); return 1; } static_always_inline int nat44_ed_alloc_i2o_addr_and_port (snat_main_t *sm, snat_address_t *addresses, snat_session_t *s, ip4_address_t i2o_addr, u16 i2o_port, u32 i2o_fib_index, ip_protocol_t proto, u32 thread_index, u32 snat_thread_index, ip4_address_t *outside_addr, u16 *outside_port) { snat_address_t *a, *ga = 0; int i; if (vec_len (addresses) > 0) { int s_addr_offset = i2o_addr.as_u32 % vec_len (addresses); for (i = s_addr_offset; i < vec_len (addresses); ++i) { a = addresses + i; if (a->fib_index == i2o_fib_index) { return nat44_ed_alloc_i2o_port ( sm, a, s, i2o_addr, i2o_port, i2o_fib_index, proto, thread_index, snat_thread_index, outside_addr, outside_port); } else if (a->fib_index == ~0) { ga = a; } } for (i = 0; i < s_addr_offset; ++i) { a = addresses + i; if (a->fib_index == i2o_fib_index) { return nat44_ed_alloc_i2o_port ( sm, a, s, i2o_addr, i2o_port, i2o_fib_index, proto, thread_index, snat_thread_index, outside_addr, outside_port); } else if (a->fib_index == ~0) { ga = a; } } if (ga) { return nat44_ed_alloc_i2o_port ( sm, a, s, i2o_addr, i2o_port, i2o_fib_index, proto, thread_index, snat_thread_index, outside_addr, outside_port); } } /* Totally out of translations to use... */ nat_ipfix_logging_addresses_exhausted (thread_index, 0); return 1; } static snat_session_t * create_session_for_static_mapping_ed ( snat_main_t *sm, vlib_buffer_t *b, ip4_address_t i2o_addr, u16 i2o_port, u32 i2o_fib_index, ip4_address_t o2i_addr, u16 o2i_port, u32 o2i_fib_index, ip_protocol_t proto, vlib_node_runtime_t *node, u32 thread_index, twice_nat_type_t twice_nat, lb_nat_type_t lb_nat, f64 now, snat_static_mapping_t *mapping) { snat_session_t *s; ip4_header_t *ip; snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index]; if (PREDICT_FALSE ( nat44_ed_maximum_sessions_exceeded (sm, o2i_fib_index, thread_index))) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED]; nat_elog_notice (sm, "maximum sessions exceeded"); return 0; } s = nat_ed_session_alloc (sm, thread_index, now, proto); if (!s) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED]; nat_elog_warn (sm, "create NAT session failed"); return 0; } ip = vlib_buffer_get_current (b); s->ext_host_addr.as_u32 = ip->src_address.as_u32; s->ext_host_port = proto == IP_PROTOCOL_ICMP ? 0 : vnet_buffer (b)->ip.reass.l4_src_port; s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING; if (lb_nat) s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING; if (lb_nat == AFFINITY_LB_NAT) s->flags |= SNAT_SESSION_FLAG_AFFINITY; s->out2in.addr = o2i_addr; s->out2in.port = o2i_port; s->out2in.fib_index = o2i_fib_index; s->in2out.addr = i2o_addr; s->in2out.port = i2o_port; s->in2out.fib_index = i2o_fib_index; s->proto = proto; if (IP_PROTOCOL_ICMP == proto) { nat_6t_o2i_flow_init (sm, thread_index, s, s->ext_host_addr, o2i_port, o2i_addr, o2i_port, o2i_fib_index, ip->protocol); nat_6t_flow_icmp_id_rewrite_set (&s->o2i, i2o_port); } else { nat_6t_o2i_flow_init (sm, thread_index, s, s->ext_host_addr, s->ext_host_port, o2i_addr, o2i_port, o2i_fib_index, ip->protocol); nat_6t_flow_dport_rewrite_set (&s->o2i, i2o_port); } nat_6t_flow_daddr_rewrite_set (&s->o2i, i2o_addr.as_u32); nat_6t_flow_txfib_rewrite_set (&s->o2i, i2o_fib_index); if (nat_ed_ses_o2i_flow_hash_add_del (sm, thread_index, s, 1)) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_HASH_ADD_FAILED]; nat_ed_session_delete (sm, s, thread_index, 1); nat_elog_warn (sm, "out2in flow hash add failed"); return 0; } if (twice_nat == TWICE_NAT || (twice_nat == TWICE_NAT_SELF && ip->src_address.as_u32 == i2o_addr.as_u32)) { int rc = 0; snat_address_t *filter = 0; // if exact address is specified use this address if (is_sm_exact_address (mapping->flags)) { snat_address_t *ap; vec_foreach (ap, sm->twice_nat_addresses) { if (mapping->pool_addr.as_u32 == ap->addr.as_u32) { filter = ap; break; } } } if (filter) { rc = nat44_ed_alloc_i2o_port ( sm, filter, s, i2o_addr, i2o_port, i2o_fib_index, proto, thread_index, tsm->snat_thread_index, &s->ext_host_nat_addr, &s->ext_host_nat_port); s->flags |= SNAT_SESSION_FLAG_EXACT_ADDRESS; } else { rc = nat44_ed_alloc_i2o_addr_and_port ( sm, sm->twice_nat_addresses, s, i2o_addr, i2o_port, i2o_fib_index, proto, thread_index, tsm->snat_thread_index, &s->ext_host_nat_addr, &s->ext_host_nat_port); } if (rc) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_OUT_OF_PORTS]; nat_ed_session_delete (sm, s, thread_index, 1); return 0; } s->flags |= SNAT_SESSION_FLAG_TWICE_NAT; nat_6t_flow_saddr_rewrite_set (&s->o2i, s->ext_host_nat_addr.as_u32); if (IP_PROTOCOL_ICMP == proto) { nat_6t_flow_icmp_id_rewrite_set (&s->o2i, s->ext_host_nat_port); } else { nat_6t_flow_sport_rewrite_set (&s->o2i, s->ext_host_nat_port); } nat_6t_l3_l4_csum_calc (&s->o2i); nat_6t_flow_daddr_rewrite_set (&s->i2o, s->ext_host_addr.as_u32); if (IP_PROTOCOL_ICMP == proto) { nat_6t_flow_icmp_id_rewrite_set (&s->i2o, s->ext_host_port); } else { nat_6t_flow_dport_rewrite_set (&s->i2o, s->ext_host_port); } nat_6t_flow_saddr_rewrite_set (&s->i2o, o2i_addr.as_u32); if (IP_PROTOCOL_ICMP == proto) { nat_6t_flow_icmp_id_rewrite_set (&s->i2o, o2i_port); } else { nat_6t_flow_sport_rewrite_set (&s->i2o, o2i_port); } nat_6t_l3_l4_csum_calc (&s->i2o); } else { if (IP_PROTOCOL_ICMP == proto) { nat_6t_i2o_flow_init (sm, thread_index, s, i2o_addr, i2o_port, s->ext_host_addr, i2o_port, i2o_fib_index, ip->protocol); } else { nat_6t_i2o_flow_init (sm, thread_index, s, i2o_addr, i2o_port, s->ext_host_addr, s->ext_host_port, i2o_fib_index, ip->protocol); } nat_6t_flow_saddr_rewrite_set (&s->i2o, o2i_addr.as_u32); if (IP_PROTOCOL_ICMP == proto) { nat_6t_flow_icmp_id_rewrite_set (&s->i2o, o2i_port); } else { nat_6t_flow_sport_rewrite_set (&s->i2o, o2i_port); } if (nat_ed_ses_i2o_flow_hash_add_del (sm, thread_index, s, 1)) { nat_elog_notice (sm, "in2out flow hash add failed"); if (nat_ed_ses_o2i_flow_hash_add_del (sm, thread_index, s, 0)) { nat_elog_warn (sm, "out2in flow hash del failed"); } nat_ed_session_delete (sm, s, thread_index, 1); return 0; } } nat_ipfix_logging_nat44_ses_create ( thread_index, s->in2out.addr.as_u32, s->out2in.addr.as_u32, s->proto, s->in2out.port, s->out2in.port, s->in2out.fib_index); nat_syslog_nat44_sadd (0, s->in2out.fib_index, &s->in2out.addr, s->in2out.port, &s->ext_host_nat_addr, s->ext_host_nat_port, &s->out2in.addr, s->out2in.port, &s->ext_host_addr, s->ext_host_port, s->proto, nat44_ed_is_twice_nat_session (s)); per_vrf_sessions_register_session (s, thread_index); return s; } static void create_bypass_for_fwd (snat_main_t *sm, vlib_buffer_t *b, snat_session_t *s, ip4_header_t *ip, u32 rx_fib_index, u32 thread_index) { clib_bihash_kv_16_8_t kv, value; snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index]; vlib_main_t *vm = vlib_get_main (); f64 now = vlib_time_now (vm); u16 lookup_sport, lookup_dport; u8 lookup_protocol; ip4_address_t lookup_saddr, lookup_daddr; if (ip->protocol == IP_PROTOCOL_ICMP) { if (nat_get_icmp_session_lookup_values (b, ip, &lookup_daddr, &lookup_sport, &lookup_saddr, &lookup_dport, &lookup_protocol)) return; } else { if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP) { lookup_sport = vnet_buffer (b)->ip.reass.l4_dst_port; lookup_dport = vnet_buffer (b)->ip.reass.l4_src_port; } else { lookup_sport = 0; lookup_dport = 0; } lookup_saddr.as_u32 = ip->dst_address.as_u32; lookup_daddr.as_u32 = ip->src_address.as_u32; lookup_protocol = ip->protocol; } init_ed_k (&kv, lookup_saddr.as_u32, lookup_sport, lookup_daddr.as_u32, lookup_dport, rx_fib_index, lookup_protocol); if (!clib_bihash_search_16_8 (&sm->flow_hash, &kv, &value)) { ASSERT (thread_index == ed_value_get_thread_index (&value)); s = pool_elt_at_index (tsm->sessions, ed_value_get_session_index (&value)); } else if (ip->protocol == IP_PROTOCOL_ICMP && icmp_type_is_error_message (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)) { return; } else { if (PREDICT_FALSE (nat44_ed_maximum_sessions_exceeded (sm, rx_fib_index, thread_index))) return; s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol); if (!s) { nat_elog_warn (sm, "create NAT session failed"); return; } s->ext_host_addr = ip->src_address; s->ext_host_port = lookup_dport; s->flags |= SNAT_SESSION_FLAG_FWD_BYPASS; s->out2in.addr = ip->dst_address; s->out2in.port = lookup_sport; s->proto = ip->protocol; s->out2in.fib_index = rx_fib_index; s->in2out.addr = s->out2in.addr; s->in2out.port = s->out2in.port; s->in2out.fib_index = s->out2in.fib_index; nat_6t_i2o_flow_init (sm, thread_index, s, ip->dst_address, lookup_sport, ip->src_address, lookup_dport, rx_fib_index, ip->protocol); nat_6t_flow_txfib_rewrite_set (&s->i2o, rx_fib_index); if (nat_ed_ses_i2o_flow_hash_add_del (sm, thread_index, s, 1)) { nat_elog_notice (sm, "in2out flow add failed"); nat_ed_session_delete (sm, s, thread_index, 1); return; } per_vrf_sessions_register_session (s, thread_index); } if (ip->protocol == IP_PROTOCOL_TCP) { nat44_set_tcp_session_state_o2i ( sm, now, s, vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags, thread_index); } /* Accounting */ nat44_session_update_counters (s, now, 0, thread_index); /* Per-user LRU list maintenance */ nat44_session_update_lru (sm, s, thread_index); } static snat_session_t * nat44_ed_out2in_slowpath_unknown_proto (snat_main_t *sm, vlib_buffer_t *b, ip4_header_t *ip, u32 rx_fib_index, u32 thread_index, f64 now, vlib_main_t *vm, vlib_node_runtime_t *node) { snat_static_mapping_t *m; snat_session_t *s; if (PREDICT_FALSE ( nat44_ed_maximum_sessions_exceeded (sm, rx_fib_index, thread_index))) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED]; nat_elog_notice (sm, "maximum sessions exceeded"); return 0; } m = nat44_ed_sm_o2i_lookup (sm, ip->dst_address, 0, 0, ip->protocol); if (!m) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION]; return 0; } /* Create a new session */ s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol); if (!s) { b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED]; nat_elog_warn (sm, "create NAT session failed"); return 0; } s->ext_host_addr.as_u32 = ip->src_address.as_u32; s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING; s->out2in.addr.as_u32 = ip->dst_address.as_u32; s->out2in.fib_index = rx_fib_index; s->in2out.addr.as_u32 = m->local_addr.as_u32; s->in2out.fib_index = m->fib_index; s->in2out.port = s->out2in.port = ip->protocol; nat_6t_o2i_flow_init (sm, thread_index, s, ip->dst_address, 0, ip->src_address, 0, m->fib_index, ip->protocol); nat_6t_flow_saddr_rewrite_set (&s->i2o, ip->dst_address.as_u32); if (nat_ed_ses_i2o_flow_hash_add_del (sm, thread_index, s, 1)) { nat_elog_notice (sm, "in2out key add failed"); nat_ed_session_delete (sm, s, thread_index, 1); return NULL; } nat_6t_o2i_flow_init (sm, thread_index, s, ip->src_address, 0, ip->dst_address, 0, rx_fib_index, ip->protocol); nat_6t_flow_daddr_rewrite_set (&s->o2i, m->local_addr.as_u32); nat_6t_flow_txfib_rewrite_set (&s->o2i, m->fib_index); if (nat_ed_ses_o2i_flow_hash_add_del (sm, thread_index, s, 1)) { nat_elog_notice (sm, "out2in flow hash add failed"); nat_ed_session_delete (sm, s, thread_index, 1); return NULL; } per_vrf_sessions_register_session (s, thread_index); /* Accounting */ nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b), thread_index); /* Per-user LRU list maintenance */ nat44_session_update_lru (sm, s, thread_index); return s; } static inline uword nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame, int is_multi_worker) { u32 n_left_from, *from; snat_main_t *sm = &snat_main; f64 now = vlib_time_now (vm); u32 thread_index = vm->thread_index; snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index]; from = vlib_frame_vector_args (frame); n_left_from = frame->n_vectors; vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs; u16 nexts[VLIB_FRAME_SIZE], *next = nexts; vlib_get_buffers (vm, from, b, n_left_from); while (n_left_from > 0) { vlib_buffer_t *b0; u32 sw_if_index0, rx_fib_index0; ip_protocol_t proto0; ip4_header_t *ip0; snat_session_t *s0 = 0; clib_bihash_kv_16_8_t kv0 = {}, value0; nat_translation_error_e translation_error = NAT_ED_TRNSL_ERR_SUCCESS; nat_slow_path_reason_e slow_path_reason = NAT_ED_SP_REASON_NO_REASON; nat_6t_flow_t *f = 0; nat_6t_t lookup; int lookup_skipped = 0; b0 = *b; b++; /* Prefetch next iteration. */ if (PREDICT_TRUE (n_left_from >= 2)) { vlib_buffer_t *p2; p2 = *b; vlib_prefetch_buffer_header (p2, LOAD); clib_prefetch_load (p2->data); } next[0] = vnet_buffer2 (b0)->nat.arc_next; lookup.sport = vnet_buffer (b0)->ip.reass.l4_src_port; lookup.dport = vnet_buffer (b0)->ip.reass.l4_dst_port; vnet_buffer (b0)->snat.flags = 0; ip0 = vlib_buffer_get_current (b0); sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX]; rx_fib_index0 = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0); lookup.fib_index = rx_fib_index0; if (PREDICT_FALSE (ip0->ttl == 1)) { vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded, ICMP4_time_exceeded_ttl_exceeded_in_transit, 0); next[0] = NAT_NEXT_ICMP_ERROR; goto trace0; } proto0 = ip0->protocol; if (PREDICT_FALSE (proto0 == IP_PROTOCOL_ICMP)) { if (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags != ICMP4_echo_request && vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags != ICMP4_echo_reply && !icmp_type_is_error_message ( vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags)) { b0->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE]; next[0] = NAT_NEXT_DROP; goto trace0; } int err = nat_get_icmp_session_lookup_values ( b0, ip0, &lookup.saddr, &lookup.sport, &lookup.daddr, &lookup.dport, &lookup.proto); if (err != 0) { b0->error = node->errors[err]; next[0] = NAT_NEXT_DROP; goto trace0; } } else { lookup.saddr.as_u32 = ip0->src_address.as_u32; lookup.daddr.as_u32 = ip0->dst_address.as_u32; lookup.proto = ip0->protocol; } /* there might be a stashed index in vnet_buffer2 from handoff or * classify node, see if it can be used */ if (is_multi_worker && !pool_is_free_index (tsm->sessions, vnet_buffer2 (b0)->nat.cached_session_index)) { s0 = pool_elt_at_index (tsm->sessions, vnet_buffer2 (b0)->nat.cached_session_index); if (PREDICT_TRUE (nat_6t_t_eq (&s0->o2i.match, &lookup)) || (s0->flags & SNAT_SESSION_FLAG_TWICE_NAT && nat_6t_t_eq (&s0->i2o.match, &lookup))) { /* yes, this is the droid we're looking for */ lookup_skipped = 1; goto skip_lookup; } s0 = NULL; } init_ed_k (&kv0, lookup.saddr.as_u32, lookup.sport, lookup.daddr.as_u32, lookup.dport, lookup.fib_index, lookup.proto); // lookup flow if (clib_bihash_search_16_8 (&sm->flow_hash, &kv0, &value0)) { // flow does not exist go slow path slow_path_reason = NAT_ED_SP_REASON_LOOKUP_FAILED; next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH; goto trace0; } ASSERT (thread_index == ed_value_get_thread_index (&value0)); s0 = pool_elt_at_index (tsm->sessions, ed_value_get_session_index (&value0)); skip_lookup: ASSERT (thread_index == s0->thread_index); if (PREDICT_FALSE (per_vrf_sessions_is_expired (s0, thread_index))) { // session is closed, go slow path nat44_ed_free_session_data (sm, s0, thread_index, 0); nat_ed_session_delete (sm, s0, thread_index, 1); s0 = 0; slow_path_reason = NAT_ED_SP_REASON_VRF_EXPIRED; next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH; goto trace0; } // drop if session expired u64 sess_timeout_time; sess_timeout_time = s0->last_heard + (f64) nat44_session_get_timeout (sm, s0); if (now >= sess_timeout_time) { // session is closed, go slow path nat44_ed_free_session_data (sm, s0, thread_index, 0); nat_ed_session_delete (sm, s0, thread_index, 1); s0 = 0; slow_path_reason = NAT_ED_SP_SESS_EXPIRED; next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH; goto trace0; } if (nat_6t_t_eq (&s0->o2i.match, &lookup)) { f = &s0->o2i; } else if (s0->flags & SNAT_SESSION_FLAG_TWICE_NAT && nat_6t_t_eq (&s0->i2o.match, &lookup)) { f = &s0->i2o; } else { /* * Send DHCP packets to the ipv4 stack, or we won't * be able to use dhcp client on the outside interface */ if (PREDICT_FALSE ( proto0 == IP_PROTOCOL_UDP && (vnet_buffer (b0)->ip.reass.l4_dst_port == clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_client)))) { goto trace0; } if (!sm->forwarding_enabled) { b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION]; next[0] = NAT_NEXT_DROP; goto trace0; } else { if (nat_6t_t_eq (&s0->i2o.match, &lookup)) { f = &s0->i2o; } else { // FIXME TODO bypass ??? // create_bypass_for_fwd (sm, b0, s0, ip0, rx_fib_index0, // thread_index); translation_error = NAT_ED_TRNSL_ERR_FLOW_MISMATCH; nat44_ed_free_session_data (sm, s0, thread_index, 0); nat_ed_session_delete (sm, s0, thread_index, 1); s0 = 0; next[0] = NAT_NEXT_DROP; b0->error = node->errors[NAT_OUT2IN_ED_ERROR_TRNSL_FAILED]; goto trace0; } } } if (NAT_ED_TRNSL_ERR_SUCCESS != (translation_error = nat_6t_flow_buf_translate_o2i ( vm, sm, b0, ip0, f, proto0, 0 /* is_output_feature */))) { next[0] = NAT_NEXT_DROP; b0->error = node->errors[NAT_OUT2IN_ED_ERROR_TRNSL_FAILED]; goto trace0; } switch (proto0) { case IP_PROTOCOL_TCP: vlib_increment_simple_counter (&sm->counters.fastpath.out2in.tcp, thread_index, sw_if_index0, 1); nat44_set_tcp_session_state_o2i (sm, now, s0, vnet_buffer (b0)->ip. reass.icmp_type_or_tcp_flags, thread_index); break; case IP_PROTOCOL_UDP: vlib_increment_simple_counter (&sm->counters.fastpath.out2in.udp, thread_index, sw_if_index0, 1); break; case IP_PROTOCOL_ICMP: vlib_increment_simple_counter (&sm->counters.fastpath.out2in.icmp, thread_index, sw_if_index0, 1); break; default: vlib_increment_simple_counter (&sm->counters.fastpath.out2in.other, thread_index, sw_if_index0, 1); break; } /* Accounting */ nat44_session_update_counters (s0, now, vlib_buffer_length_in_chain (vm, b0), thread_index); /* Per-user LRU list maintenance */ nat44_session_update_lru (sm, s0, thread_index); trace0: if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { nat44_ed_out2in_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->sw_if_index = sw_if_index0; t->next_index = next[0]; t->is_slow_path = 0; t->translation_error = translation_error; clib_memcpy (&t->search_key, &kv0, sizeof (t->search_key)); t->lookup_skipped = lookup_skipped; t->slow_path_reason = slow_path_reason; if (s0) { t->session_index = s0 - tsm->sessions; clib_memcpy (&t->i2of, &s0->i2o, sizeof (t->i2of)); clib_memcpy (&t->o2if, &s0->o2i, sizeof (t->o2if)); t->translation_via_i2of = (&s0->i2o == f); t->tcp_state = s0->tcp_state; } else { t->session_index = ~0; } } if (next[0] == NAT_NEXT_DROP) { vlib_increment_simple_counter (&sm->counters.fastpath.out2in.drops, thread_index, sw_if_index0, 1); } n_left_from--; next++; } vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts, frame->n_vectors); return frame->n_vectors; } static inline uword nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_left_from, *from; snat_main_t *sm = &snat_main; f64 now = vlib_time_now (vm); u32 thread_index = vm->thread_index; snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index]; snat_static_mapping_t *m; from = vlib_frame_vector_args (frame); n_left_from = frame->n_vectors; vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs; u16 nexts[VLIB_FRAME_SIZE], *next = nexts; vlib_get_buffers (vm, from, b, n_left_from); while (n_left_from > 0) { vlib_buffer_t *b0; u32 sw_if_index0, rx_fib_index0; ip_protocol_t proto0; ip4_header_t *ip0; udp_header_t *udp0; icmp46_header_t *icmp0; snat_session_t *s0 = 0; clib_bihash_kv_16_8_t kv0 = {}, value0; lb_nat_type_t lb_nat0; twice_nat_type_t twice_nat0; u8 identity_nat0; ip4_address_t sm_addr; u16 sm_port; u32 sm_fib_index; nat_translation_error_e translation_error = NAT_ED_TRNSL_ERR_SUCCESS; b0 = *b; next[0] = vnet_buffer2 (b0)->nat.arc_next; vnet_buffer (b0)->snat.flags = 0; ip0 = vlib_buffer_get_current (b0); sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX]; rx_fib_index0 = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4, sw_if_index0); if (PREDICT_FALSE (ip0->ttl == 1)) { vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded, ICMP4_time_exceeded_ttl_exceeded_in_transit, 0); next[0] = NAT_NEXT_ICMP_ERROR; goto trace0; } udp0 = ip4_next_header (ip0); icmp0 = (icmp46_header_t *) udp0; proto0 = ip0->protocol; if (PREDICT_FALSE (nat44_ed_is_unk_proto (proto0))) { s0 = nat44_ed_out2in_slowpath_unknown_proto ( sm, b0, ip0, rx_fib_index0, thread_index, now, vm, node); if (!sm->forwarding_enabled) { if (!s0) next[0] = NAT_NEXT_DROP; } if (NAT_NEXT_DROP != next[0] && s0 && NAT_ED_TRNSL_ERR_SUCCESS != (translation_error = nat_6t_flow_buf_translate_o2i ( vm, sm, b0, ip0, &s0->o2i, proto0, 0 /* is_output_feature */))) { next[0] = NAT_NEXT_DROP; b0->error = node->errors[NAT_OUT2IN_ED_ERROR_TRNSL_FAILED]; goto trace0; } vlib_increment_simple_counter (&sm->counters.slowpath.out2in.other, thread_index, sw_if_index0, 1); goto trace0; } if (PREDICT_FALSE (proto0 == IP_PROTOCOL_ICMP)) { next[0] = icmp_out2in_ed_slow_path (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, next[0], now, thread_index, &s0); if (NAT_NEXT_DROP != next[0] && s0 && NAT_ED_TRNSL_ERR_SUCCESS != (translation_error = nat_6t_flow_buf_translate_o2i ( vm, sm, b0, ip0, &s0->o2i, proto0, 0 /* is_output_feature */))) { next[0] = NAT_NEXT_DROP; b0->error = node->errors[NAT_OUT2IN_ED_ERROR_TRNSL_FAILED]; goto trace0; } if (NAT_NEXT_DROP != next[0]) { vlib_increment_simple_counter ( &sm->counters.slowpath.out2in.icmp, thread_index, sw_if_index0, 1); } goto trace0; } init_ed_k ( &kv0, ip0->src_address.as_u32, vnet_buffer (b0)->ip.reass.l4_src_port, ip0->dst_address.as_u32, vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0, ip0->protocol); s0 = NULL; if (!clib_bihash_search_16_8 (&sm->flow_hash, &kv0, &value0)) { ASSERT (thread_index == ed_value_get_thread_index (&value0)); s0 = pool_elt_at_index (tsm->sessions, ed_value_get_session_index (&value0)); } if (!s0) { /* Try to match static mapping by external address and port, destination address and port in packet */ if (snat_static_mapping_match ( vm, ip0->dst_address, vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0, proto0, &sm_addr, &sm_port, &sm_fib_index, 1, 0, &twice_nat0, &lb_nat0, &ip0->src_address, &identity_nat0, &m)) { /* * Send DHCP packets to the ipv4 stack, or we won't * be able to use dhcp client on the outside interface */ if (PREDICT_FALSE ( proto0 == IP_PROTOCOL_UDP && (vnet_buffer (b0)->ip.reass.l4_dst_port == clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_client)))) { goto trace0; } if (!sm->forwarding_enabled) { b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION]; next[0] = NAT_NEXT_DROP; } else { if (next_src_nat ( sm, ip0, vnet_buffer (b0)->ip.reass.l4_src_port, vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0)) { next[0] = NAT_NEXT_IN2OUT_ED_FAST_PATH; } else { create_bypass_for_fwd (sm, b0, s0, ip0, rx_fib_index0, thread_index); } } goto trace0; } if (PREDICT_FALSE (identity_nat0)) goto trace0; if ((proto0 == IP_PROTOCOL_TCP) && !tcp_flags_is_init ( vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags)) { b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN]; next[0] = NAT_NEXT_DROP; goto trace0; } /* Create session initiated by host from external network */ s0 = create_session_for_static_mapping_ed ( sm, b0, sm_addr, sm_port, sm_fib_index, ip0->dst_address, vnet_buffer (b0)->ip.reass.l4_dst_port, rx_fib_index0, proto0, node, thread_index, twice_nat0, lb_nat0, now, m); if (!s0) { next[0] = NAT_NEXT_DROP; goto trace0; } } if (NAT_ED_TRNSL_ERR_SUCCESS != (translation_error = nat_6t_flow_buf_translate_o2i ( vm, sm, b0, ip0, &s0->o2i, proto0, 0 /* is_output_feature */))) { next[0] = NAT_NEXT_DROP; goto trace0; } if (PREDICT_TRUE (proto0 == IP_PROTOCOL_TCP)) { vlib_increment_simple_counter (&sm->counters.slowpath.out2in.tcp, thread_index, sw_if_index0, 1); nat44_set_tcp_session_state_o2i (sm, now, s0, vnet_buffer (b0)->ip. reass.icmp_type_or_tcp_flags, thread_index); } else { vlib_increment_simple_counter (&sm->counters.slowpath.out2in.udp, thread_index, sw_if_index0, 1); } /* Accounting */ nat44_session_update_counters (s0, now, vlib_buffer_length_in_chain (vm, b0), thread_index); /* Per-user LRU list maintenance */ nat44_session_update_lru (sm, s0, thread_index); trace0: if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { nat44_ed_out2in_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->sw_if_index = sw_if_index0; t->next_index = next[0]; t->is_slow_path = 1; t->translation_error = translation_error; clib_memcpy (&t->search_key, &kv0, sizeof (t->search_key)); if (s0) { t->session_index = s0 - tsm->sessions; clib_memcpy (&t->i2of, &s0->i2o, sizeof (t->i2of)); clib_memcpy (&t->o2if, &s0->o2i, sizeof (t->o2if)); t->tcp_state = s0->tcp_state; } else { t->session_index = ~0; } } if (next[0] == NAT_NEXT_DROP) { vlib_increment_simple_counter (&sm->counters.slowpath.out2in.drops, thread_index, sw_if_index0, 1); } n_left_from--; next++; b++; } vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts, frame->n_vectors); return frame->n_vectors; } VLIB_NODE_FN (nat44_ed_out2in_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { if (snat_main.num_workers > 1) { return nat44_ed_out2in_fast_path_node_fn_inline (vm, node, frame, 1); } else { return nat44_ed_out2in_fast_path_node_fn_inline (vm, node, frame, 0); } } VLIB_REGISTER_NODE (nat44_ed_out2in_node) = { .name = "nat44-ed-out2in", .vector_size = sizeof (u32), .sibling_of = "nat-default", .format_trace = format_nat44_ed_out2in_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings), .error_strings = nat_out2in_ed_error_strings, .runtime_data_bytes = sizeof (snat_runtime_t), }; VLIB_NODE_FN (nat44_ed_out2in_slowpath_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { return nat44_ed_out2in_slow_path_node_fn_inline (vm, node, frame); } VLIB_REGISTER_NODE (nat44_ed_out2in_slowpath_node) = { .name = "nat44-ed-out2in-slowpath", .vector_size = sizeof (u32), .sibling_of = "nat-default", .format_trace = format_nat44_ed_out2in_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings), .error_strings = nat_out2in_ed_error_strings, .runtime_data_bytes = sizeof (snat_runtime_t), }; static u8 * format_nat_pre_trace (u8 * s, va_list * args) { CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *); return format (s, "out2in next_index %d arc_next_index %d", t->next_index, t->arc_next_index); } VLIB_NODE_FN (nat_pre_out2in_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { return nat_pre_node_fn_inline (vm, node, frame, NAT_NEXT_OUT2IN_ED_FAST_PATH); } VLIB_REGISTER_NODE (nat_pre_out2in_node) = { .name = "nat-pre-out2in", .vector_size = sizeof (u32), .sibling_of = "nat-default", .format_trace = format_nat_pre_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = 0, }; /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */