/* * Copyright (c) 2016 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include typedef struct { u32 sw_if_index; u32 next_index; u32 session_index; } snat_out2in_trace_t; typedef struct { u32 next_worker_index; u8 do_handoff; } snat_out2in_worker_handoff_trace_t; /* packet trace format function */ static u8 * format_snat_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 *); snat_out2in_trace_t * t = va_arg (*args, snat_out2in_trace_t *); s = format (s, "SNAT_OUT2IN: sw_if_index %d, next index %d, session index %d", t->sw_if_index, t->next_index, t->session_index); return s; } static u8 * format_snat_out2in_fast_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 *); snat_out2in_trace_t * t = va_arg (*args, snat_out2in_trace_t *); s = format (s, "SNAT_OUT2IN_FAST: sw_if_index %d, next index %d", t->sw_if_index, t->next_index); return s; } static u8 * format_snat_out2in_worker_handoff_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 *); snat_out2in_worker_handoff_trace_t * t = va_arg (*args, snat_out2in_worker_handoff_trace_t *); char * m; m = t->do_handoff ? "next worker" : "same worker"; s = format (s, "SNAT_OUT2IN_WORKER_HANDOFF: %s %d", m, t->next_worker_index); return s; } vlib_node_registration_t snat_out2in_node; vlib_node_registration_t snat_out2in_fast_node; vlib_node_registration_t snat_out2in_worker_handoff_node; #define foreach_snat_out2in_error \ _(UNSUPPORTED_PROTOCOL, "Unsupported protocol") \ _(OUT2IN_PACKETS, "Good out2in packets processed") \ _(BAD_ICMP_TYPE, "icmp type not echo-reply") \ _(NO_TRANSLATION, "No translation") typedef enum { #define _(sym,str) SNAT_OUT2IN_ERROR_##sym, foreach_snat_out2in_error #undef _ SNAT_OUT2IN_N_ERROR, } snat_out2in_error_t; static char * snat_out2in_error_strings[] = { #define _(sym,string) string, foreach_snat_out2in_error #undef _ }; typedef enum { SNAT_OUT2IN_NEXT_DROP, SNAT_OUT2IN_NEXT_LOOKUP, SNAT_OUT2IN_NEXT_ICMP_ERROR, SNAT_OUT2IN_N_NEXT, } snat_out2in_next_t; /** * @brief Create session for static mapping. * * Create NAT session initiated by host from external network with static * mapping. * * @param sm SNAT main. * @param b0 Vlib buffer. * @param in2out In2out SNAT session key. * @param out2in Out2in SNAT session key. * @param node Vlib node. * * @returns SNAT session if successfully created otherwise 0. */ static inline snat_session_t * create_session_for_static_mapping (snat_main_t *sm, vlib_buffer_t *b0, snat_session_key_t in2out, snat_session_key_t out2in, vlib_node_runtime_t * node, u32 cpu_index) { snat_user_t *u; snat_user_key_t user_key; snat_session_t *s; clib_bihash_kv_8_8_t kv0, value0; dlist_elt_t * per_user_translation_list_elt; dlist_elt_t * per_user_list_head_elt; user_key.addr = in2out.addr; user_key.fib_index = in2out.fib_index; kv0.key = user_key.as_u64; /* Ever heard of the "user" = inside ip4 address before? */ if (clib_bihash_search_8_8 (&sm->user_hash, &kv0, &value0)) { /* no, make a new one */ pool_get (sm->per_thread_data[cpu_index].users, u); memset (u, 0, sizeof (*u)); u->addr = in2out.addr; pool_get (sm->per_thread_data[cpu_index].list_pool, per_user_list_head_elt); u->sessions_per_user_list_head_index = per_user_list_head_elt - sm->per_thread_data[cpu_index].list_pool; clib_dlist_init (sm->per_thread_data[cpu_index].list_pool, u->sessions_per_user_list_head_index); kv0.value = u - sm->per_thread_data[cpu_index].users; /* add user */ clib_bihash_add_del_8_8 (&sm->user_hash, &kv0, 1 /* is_add */); /* add non-traslated packets worker lookup */ kv0.value = cpu_index; clib_bihash_add_del_8_8 (&sm->worker_by_in, &kv0, 1); } else { u = pool_elt_at_index (sm->per_thread_data[cpu_index].users, value0.value); } pool_get (sm->per_thread_data[cpu_index].sessions, s); memset (s, 0, sizeof (*s)); s->outside_address_index = ~0; s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING; u->nstaticsessions++; /* Create list elts */ pool_get (sm->per_thread_data[cpu_index].list_pool, per_user_translation_list_elt); clib_dlist_init (sm->per_thread_data[cpu_index].list_pool, per_user_translation_list_elt - sm->per_thread_data[cpu_index].list_pool); per_user_translation_list_elt->value = s - sm->per_thread_data[cpu_index].sessions; s->per_user_index = per_user_translation_list_elt - sm->per_thread_data[cpu_index].list_pool; s->per_user_list_head_index = u->sessions_per_user_list_head_index; clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool, s->per_user_list_head_index, per_user_translation_list_elt - sm->per_thread_data[cpu_index].list_pool); s->in2out = in2out; s->out2in = out2in; s->in2out.protocol = out2in.protocol; /* Add to translation hashes */ kv0.key = s->in2out.as_u64; kv0.value = s - sm->per_thread_data[cpu_index].sessions; if (clib_bihash_add_del_8_8 (&sm->in2out, &kv0, 1 /* is_add */)) clib_warning ("in2out key add failed"); kv0.key = s->out2in.as_u64; kv0.value = s - sm->per_thread_data[cpu_index].sessions; if (clib_bihash_add_del_8_8 (&sm->out2in, &kv0, 1 /* is_add */)) clib_warning ("out2in key add failed"); /* log NAT event */ snat_ipfix_logging_nat44_ses_create(s->in2out.addr.as_u32, s->out2in.addr.as_u32, s->in2out.protocol, s->in2out.port, s->out2in.port, s->in2out.fib_index); return s; } typedef struct { u16 src_port, dst_port; } tcp_udp_header_t; static inline u32 icmp_out2in_slow_path (snat_main_t *sm, vlib_buffer_t * b0, ip4_header_t * ip0, icmp46_header_t * icmp0, u32 sw_if_index0, u32 rx_fib_index0, vlib_node_runtime_t * node, u32 next0, f64 now, u32 cpu_index, snat_session_t ** p_s0) { snat_session_key_t key0, sm0; icmp_echo_header_t *echo0, *inner_echo0 = 0; ip4_header_t *inner_ip0 = 0; void *l4_header = 0; icmp46_header_t *inner_icmp0; clib_bihash_kv_8_8_t kv0, value0; snat_session_t * s0 = 0; u32 new_addr0, old_addr0; u16 old_id0, new_id0; ip_csum_t sum0; u16 checksum0; snat_runtime_t * rt = (snat_runtime_t *)node->runtime_data; u8 is_error_message = 0; echo0 = (icmp_echo_header_t *)(icmp0+1); key0.addr = ip0->dst_address; key0.fib_index = rx_fib_index0; switch(icmp0->type) { case ICMP4_destination_unreachable: case ICMP4_time_exceeded: case ICMP4_parameter_problem: case ICMP4_source_quench: case ICMP4_redirect: case ICMP4_alternate_host_address: is_error_message = 1; } if (!is_error_message) { if (PREDICT_FALSE(icmp0->type != ICMP4_echo_reply)) { b0->error = node->errors[SNAT_OUT2IN_ERROR_BAD_ICMP_TYPE]; next0 = SNAT_OUT2IN_NEXT_DROP; goto out; } key0.protocol = SNAT_PROTOCOL_ICMP; key0.port = echo0->identifier; } else { inner_ip0 = (ip4_header_t *)(echo0+1); l4_header = ip4_next_header (inner_ip0); key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol); switch (key0.protocol) { case SNAT_PROTOCOL_ICMP: inner_icmp0 = (icmp46_header_t*)l4_header; inner_echo0 = (icmp_echo_header_t *)(inner_icmp0+1); key0.port = inner_echo0->identifier; break; case SNAT_PROTOCOL_UDP: case SNAT_PROTOCOL_TCP: key0.port = ((tcp_udp_header_t*)l4_header)->src_port; break; default: b0->error = node->errors[SNAT_OUT2IN_ERROR_UNSUPPORTED_PROTOCOL]; next0 = SNAT_OUT2IN_NEXT_DROP; goto out; } } kv0.key = key0.as_u64; if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0)) { /* Try to match static mapping by external address and port, destination address and port in packet */ if (snat_static_mapping_match(sm, key0, &sm0, 1)) { ip4_address_t * first_int_addr; if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) { first_int_addr = ip4_interface_first_address (sm->ip4_main, sw_if_index0, 0 /* just want the address */); rt->cached_sw_if_index = sw_if_index0; if (first_int_addr) rt->cached_ip4_address = first_int_addr->as_u32; else rt->cached_ip4_address = 0; } /* Don't NAT packet aimed at the intfc address */ if (PREDICT_FALSE(ip0->dst_address.as_u32 == rt->cached_ip4_address)) goto out; b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; next0 = SNAT_OUT2IN_NEXT_DROP; goto out; } if (is_error_message) { next0 = SNAT_OUT2IN_NEXT_DROP; goto out; } /* Create session initiated by host from external network */ s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node, cpu_index); if (!s0) { next0 = SNAT_OUT2IN_NEXT_DROP; goto out; } } else s0 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions, value0.value); sum0 = ip_incremental_checksum (0, icmp0, ntohs(ip0->length) - ip4_header_bytes (ip0)); checksum0 = ~ip_csum_fold (sum0); if (checksum0 != 0 && checksum0 != 0xffff) { next0 = SNAT_OUT2IN_NEXT_DROP; goto out; } old_addr0 = ip0->dst_address.as_u32; ip0->dst_address = s0->in2out.addr; new_addr0 = ip0->dst_address.as_u32; vnet_buffer(b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index; sum0 = ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); ip0->checksum = ip_csum_fold (sum0); if (!is_error_message) { old_id0 = echo0->identifier; new_id0 = s0->in2out.port; echo0->identifier = new_id0; sum0 = icmp0->checksum; sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t, identifier /* changed member */); icmp0->checksum = ip_csum_fold (sum0); } else { if (!ip4_header_checksum_is_valid (inner_ip0)) { next0 = SNAT_OUT2IN_NEXT_DROP; goto out; } old_addr0 = inner_ip0->src_address.as_u32; inner_ip0->src_address = s0->in2out.addr; new_addr0 = inner_ip0->src_address.as_u32; sum0 = icmp0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, src_address /* changed member */); icmp0->checksum = ip_csum_fold (sum0); switch (key0.protocol) { case SNAT_PROTOCOL_ICMP: old_id0 = inner_echo0->identifier; new_id0 = s0->in2out.port; inner_echo0->identifier = new_id0; sum0 = icmp0->checksum; sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t, identifier); icmp0->checksum = ip_csum_fold (sum0); break; case SNAT_PROTOCOL_UDP: case SNAT_PROTOCOL_TCP: old_id0 = ((tcp_udp_header_t*)l4_header)->src_port; new_id0 = s0->in2out.port; ((tcp_udp_header_t*)l4_header)->src_port = new_id0; sum0 = icmp0->checksum; sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t, src_port); icmp0->checksum = ip_csum_fold (sum0); break; default: ASSERT(0); } } /* Accounting */ s0->last_heard = now; s0->total_pkts++; s0->total_bytes += vlib_buffer_length_in_chain (sm->vlib_main, b0); /* Per-user LRU list maintenance for dynamic translation */ if (!snat_is_session_static (s0)) { clib_dlist_remove (sm->per_thread_data[cpu_index].list_pool, s0->per_user_index); clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool, s0->per_user_list_head_index, s0->per_user_index); } out: *p_s0 = s0; return next0; } static uword snat_out2in_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_left_from, * from, * to_next; snat_out2in_next_t next_index; u32 pkts_processed = 0; snat_main_t * sm = &snat_main; f64 now = vlib_time_now (vm); u32 cpu_index = os_get_cpu_number (); from = vlib_frame_vector_args (frame); n_left_from = frame->n_vectors; next_index = node->cached_next_index; while (n_left_from > 0) { u32 n_left_to_next; vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (n_left_from >= 4 && n_left_to_next >= 2) { u32 bi0, bi1; vlib_buffer_t * b0, * b1; u32 next0 = SNAT_OUT2IN_NEXT_LOOKUP; u32 next1 = SNAT_OUT2IN_NEXT_LOOKUP; u32 sw_if_index0, sw_if_index1; ip4_header_t * ip0, *ip1; ip_csum_t sum0, sum1; u32 new_addr0, old_addr0; u16 new_port0, old_port0; u32 new_addr1, old_addr1; u16 new_port1, old_port1; udp_header_t * udp0, * udp1; tcp_header_t * tcp0, * tcp1; icmp46_header_t * icmp0, * icmp1; snat_session_key_t key0, key1, sm0, sm1; u32 rx_fib_index0, rx_fib_index1; u32 proto0, proto1; snat_session_t * s0 = 0, * s1 = 0; clib_bihash_kv_8_8_t kv0, kv1, value0, value1; /* Prefetch next iteration. */ { vlib_buffer_t * p2, * p3; p2 = vlib_get_buffer (vm, from[2]); p3 = vlib_get_buffer (vm, from[3]); vlib_prefetch_buffer_header (p2, LOAD); vlib_prefetch_buffer_header (p3, LOAD); CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE); CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE); } /* speculatively enqueue b0 and b1 to the current next frame */ to_next[0] = bi0 = from[0]; to_next[1] = bi1 = from[1]; from += 2; to_next += 2; n_left_from -= 2; n_left_to_next -= 2; b0 = vlib_get_buffer (vm, bi0); b1 = vlib_get_buffer (vm, bi1); ip0 = vlib_buffer_get_current (b0); udp0 = ip4_next_header (ip0); tcp0 = (tcp_header_t *) udp0; icmp0 = (icmp46_header_t *) udp0; sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX]; rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index, sw_if_index0); proto0 = ip_proto_to_snat_proto (ip0->protocol); if (PREDICT_FALSE (proto0 == ~0)) goto trace0; 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); next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR; goto trace0; } if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP)) { next0 = icmp_out2in_slow_path (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, next0, now, cpu_index, &s0); goto trace0; } key0.addr = ip0->dst_address; key0.port = udp0->dst_port; key0.protocol = proto0; key0.fib_index = rx_fib_index0; kv0.key = key0.as_u64; if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0)) { /* Try to match static mapping by external address and port, destination address and port in packet */ if (snat_static_mapping_match(sm, key0, &sm0, 1)) { b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; /* * Send DHCP packets to the ipv4 stack, or we won't * be able to use dhcp client on the outside interface */ if (proto0 != SNAT_PROTOCOL_UDP || (udp0->dst_port != clib_host_to_net_u16(UDP_DST_PORT_dhcp_to_client))) next0 = SNAT_OUT2IN_NEXT_DROP; goto trace0; } /* Create session initiated by host from external network */ s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node, cpu_index); if (!s0) { b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; next0 = SNAT_OUT2IN_NEXT_DROP; goto trace0; } } else s0 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions, value0.value); old_addr0 = ip0->dst_address.as_u32; ip0->dst_address = s0->in2out.addr; new_addr0 = ip0->dst_address.as_u32; vnet_buffer(b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index; sum0 = ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); ip0->checksum = ip_csum_fold (sum0); if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP)) { old_port0 = tcp0->ports.dst; tcp0->ports.dst = s0->in2out.port; new_port0 = tcp0->ports.dst; sum0 = tcp0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t /* cheat */, length /* changed member */); tcp0->checksum = ip_csum_fold(sum0); } else { old_port0 = udp0->dst_port; udp0->dst_port = s0->in2out.port; udp0->checksum = 0; } /* Accounting */ s0->last_heard = now; s0->total_pkts++; s0->total_bytes += vlib_buffer_length_in_chain (vm, b0); /* Per-user LRU list maintenance for dynamic translation */ if (!snat_is_session_static (s0)) { clib_dlist_remove (sm->per_thread_data[cpu_index].list_pool, s0->per_user_index); clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool, s0->per_user_list_head_index, s0->per_user_index); } trace0: if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { snat_out2in_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->sw_if_index = sw_if_index0; t->next_index = next0; t->session_index = ~0; if (s0) t->session_index = s0 - sm->per_thread_data[cpu_index].sessions; } pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP; ip1 = vlib_buffer_get_current (b1); udp1 = ip4_next_header (ip1); tcp1 = (tcp_header_t *) udp1; icmp1 = (icmp46_header_t *) udp1; sw_if_index1 = vnet_buffer(b1)->sw_if_index[VLIB_RX]; rx_fib_index1 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index, sw_if_index1); proto1 = ip_proto_to_snat_proto (ip1->protocol); if (PREDICT_FALSE (proto1 == ~0)) goto trace1; if (PREDICT_FALSE(ip0->ttl == 1)) { vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0; icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded, ICMP4_time_exceeded_ttl_exceeded_in_transit, 0); next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR; goto trace1; } if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP)) { next1 = icmp_out2in_slow_path (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node, next1, now, cpu_index, &s1); goto trace1; } key1.addr = ip1->dst_address; key1.port = udp1->dst_port; key1.protocol = proto1; key1.fib_index = rx_fib_index1; kv1.key = key1.as_u64; if (clib_bihash_search_8_8 (&sm->out2in, &kv1, &value1)) { /* Try to match static mapping by external address and port, destination address and port in packet */ if (snat_static_mapping_match(sm, key1, &sm1, 1)) { b1->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; /* * Send DHCP packets to the ipv4 stack, or we won't * be able to use dhcp client on the outside interface */ if (proto1 != SNAT_PROTOCOL_UDP || (udp1->dst_port != clib_host_to_net_u16(UDP_DST_PORT_dhcp_to_client))) next1 = SNAT_OUT2IN_NEXT_DROP; goto trace1; } /* Create session initiated by host from external network */ s1 = create_session_for_static_mapping(sm, b1, sm1, key1, node, cpu_index); if (!s1) { b1->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; next1 = SNAT_OUT2IN_NEXT_DROP; goto trace1; } } else s1 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions, value1.value); old_addr1 = ip1->dst_address.as_u32; ip1->dst_address = s1->in2out.addr; new_addr1 = ip1->dst_address.as_u32; vnet_buffer(b1)->sw_if_index[VLIB_TX] = s1->in2out.fib_index; sum1 = ip1->checksum; sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t, dst_address /* changed member */); ip1->checksum = ip_csum_fold (sum1); if (PREDICT_TRUE(proto1 == SNAT_PROTOCOL_TCP)) { old_port1 = tcp1->ports.dst; tcp1->ports.dst = s1->in2out.port; new_port1 = tcp1->ports.dst; sum1 = tcp1->checksum; sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t, dst_address /* changed member */); sum1 = ip_csum_update (sum1, old_port1, new_port1, ip4_header_t /* cheat */, length /* changed member */); tcp1->checksum = ip_csum_fold(sum1); } else { old_port1 = udp1->dst_port; udp1->dst_port = s1->in2out.port; udp1->checksum = 0; } /* Accounting */ s1->last_heard = now; s1->total_pkts++; s1->total_bytes += vlib_buffer_length_in_chain (vm, b1); /* Per-user LRU list maintenance for dynamic translation */ if (!snat_is_session_static (s1)) { clib_dlist_remove (sm->per_thread_data[cpu_index].list_pool, s1->per_user_index); clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool, s1->per_user_list_head_index, s1->per_user_index); } trace1: if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) && (b1->flags & VLIB_BUFFER_IS_TRACED))) { snat_out2in_trace_t *t = vlib_add_trace (vm, node, b1, sizeof (*t)); t->sw_if_index = sw_if_index1; t->next_index = next1; t->session_index = ~0; if (s1) t->session_index = s1 - sm->per_thread_data[cpu_index].sessions; } pkts_processed += next1 != SNAT_OUT2IN_NEXT_DROP; /* verify speculative enqueues, maybe switch current next frame */ vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next, n_left_to_next, bi0, bi1, next0, next1); } while (n_left_from > 0 && n_left_to_next > 0) { u32 bi0; vlib_buffer_t * b0; u32 next0 = SNAT_OUT2IN_NEXT_LOOKUP; u32 sw_if_index0; ip4_header_t * ip0; ip_csum_t sum0; u32 new_addr0, old_addr0; u16 new_port0, old_port0; udp_header_t * udp0; tcp_header_t * tcp0; icmp46_header_t * icmp0; snat_session_key_t key0, sm0; u32 rx_fib_index0; u32 proto0; snat_session_t * s0 = 0; clib_bihash_kv_8_8_t kv0, value0; /* speculatively enqueue b0 to the current next frame */ bi0 = from[0]; to_next[0] = bi0; from += 1; to_next += 1; n_left_from -= 1; n_left_to_next -= 1; b0 = vlib_get_buffer (vm, bi0); ip0 = vlib_buffer_get_current (b0); udp0 = ip4_next_header (ip0); tcp0 = (tcp_header_t *) udp0; icmp0 = (icmp46_header_t *) udp0; sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX]; rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index, sw_if_index0); proto0 = ip_proto_to_snat_proto (ip0->protocol); if (PREDICT_FALSE (proto0 == ~0)) goto trace00; 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); next0 = SNAT_OUT2IN_NEXT_ICMP_ERROR; goto trace00; } if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP)) { next0 = icmp_out2in_slow_path (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, next0, now, cpu_index, &s0); goto trace00; } key0.addr = ip0->dst_address; key0.port = udp0->dst_port; key0.protocol = proto0; key0.fib_index = rx_fib_index0; kv0.key = key0.as_u64; if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0)) { /* Try to match static mapping by external address and port, destination address and port in packet */ if (snat_static_mapping_match(sm, key0, &sm0, 1)) { b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; /* * Send DHCP packets to the ipv4 stack, or we won't * be able to use dhcp client on the outside interface */ if (proto0 != SNAT_PROTOCOL_UDP || (udp0->dst_port != clib_host_to_net_u16(UDP_DST_PORT_dhcp_to_client))) next0 = SNAT_OUT2IN_NEXT_DROP; goto trace00; } /* Create session initiated by host from external network */ s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node, cpu_index); if (!s0) { b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; next0 = SNAT_OUT2IN_NEXT_DROP; goto trace00; } } else s0 = pool_elt_at_index (sm->per_thread_data[cpu_index].sessions, value0.value); old_addr0 = ip0->dst_address.as_u32; ip0->dst_address = s0->in2out.addr; new_addr0 = ip0->dst_address.as_u32; vnet_buffer(b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index; sum0 = ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); ip0->checksum = ip_csum_fold (sum0); if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP)) { old_port0 = tcp0->ports.dst; tcp0->ports.dst = s0->in2out.port; new_port0 = tcp0->ports.dst; sum0 = tcp0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t /* cheat */, length /* changed member */); tcp0->checksum = ip_csum_fold(sum0); } else { old_port0 = udp0->dst_port; udp0->dst_port = s0->in2out.port; udp0->checksum = 0; } /* Accounting */ s0->last_heard = now; s0->total_pkts++; s0->total_bytes += vlib_buffer_length_in_chain (vm, b0); /* Per-user LRU list maintenance for dynamic translation */ if (!snat_is_session_static (s0)) { clib_dlist_remove (sm->per_thread_data[cpu_index].list_pool, s0->per_user_index); clib_dlist_addtail (sm->per_thread_data[cpu_index].list_pool, s0->per_user_list_head_index, s0->per_user_index); } trace00: if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { snat_out2in_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->sw_if_index = sw_if_index0; t->next_index = next0; t->session_index = ~0; if (s0) t->session_index = s0 - sm->per_thread_data[cpu_index].sessions; } pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP; /* verify speculative enqueue, maybe switch current next frame */ vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, bi0, next0); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } vlib_node_increment_counter (vm, snat_out2in_node.index, SNAT_OUT2IN_ERROR_OUT2IN_PACKETS, pkts_processed); return frame->n_vectors; } VLIB_REGISTER_NODE (snat_out2in_node) = { .function = snat_out2in_node_fn, .name = "snat-out2in", .vector_size = sizeof (u32), .format_trace = format_snat_out2in_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN(snat_out2in_error_strings), .error_strings = snat_out2in_error_strings, .runtime_data_bytes = sizeof (snat_runtime_t), .n_next_nodes = SNAT_OUT2IN_N_NEXT, /* edit / add dispositions here */ .next_nodes = { [SNAT_OUT2IN_NEXT_DROP] = "error-drop", [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup", [SNAT_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error", }, }; VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_node, snat_out2in_node_fn); static uword snat_out2in_worker_handoff_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { snat_main_t *sm = &snat_main; vlib_thread_main_t *tm = vlib_get_thread_main (); u32 n_left_from, *from, *to_next = 0; static __thread vlib_frame_queue_elt_t **handoff_queue_elt_by_worker_index; static __thread vlib_frame_queue_t **congested_handoff_queue_by_worker_index = 0; vlib_frame_queue_elt_t *hf = 0; vlib_frame_t *f = 0; int i; u32 n_left_to_next_worker = 0, *to_next_worker = 0; u32 next_worker_index = 0; u32 current_worker_index = ~0; u32 cpu_index = os_get_cpu_number (); ASSERT (vec_len (sm->workers)); if (PREDICT_FALSE (handoff_queue_elt_by_worker_index == 0)) { vec_validate (handoff_queue_elt_by_worker_index, tm->n_vlib_mains - 1); vec_validate_init_empty (congested_handoff_queue_by_worker_index, sm->first_worker_index + sm->num_workers - 1, (vlib_frame_queue_t *) (~0)); } from = vlib_frame_vector_args (frame); n_left_from = frame->n_vectors; while (n_left_from > 0) { u32 bi0; vlib_buffer_t *b0; u32 sw_if_index0; u32 rx_fib_index0; ip4_header_t * ip0; udp_header_t * udp0; snat_worker_key_t key0; clib_bihash_kv_8_8_t kv0, value0; u8 do_handoff; bi0 = from[0]; from += 1; n_left_from -= 1; b0 = vlib_get_buffer (vm, bi0); sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX]; rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index(sw_if_index0); ip0 = vlib_buffer_get_current (b0); udp0 = ip4_next_header (ip0); key0.addr = ip0->dst_address; key0.port = udp0->dst_port; key0.fib_index = rx_fib_index0; if (PREDICT_FALSE(ip0->protocol == IP_PROTOCOL_ICMP)) { icmp46_header_t * icmp0 = (icmp46_header_t *) udp0; icmp_echo_header_t *echo0 = (icmp_echo_header_t *)(icmp0+1); key0.port = echo0->identifier; } kv0.key = key0.as_u64; /* Ever heard of of the "user" before? */ if (clib_bihash_search_8_8 (&sm->worker_by_out, &kv0, &value0)) { key0.port = 0; kv0.key = key0.as_u64; if (clib_bihash_search_8_8 (&sm->worker_by_out, &kv0, &value0)) { /* No, assign next available worker (RR) */ next_worker_index = sm->first_worker_index; if (vec_len (sm->workers)) { next_worker_index += sm->workers[sm->next_worker++ % _vec_len (sm->workers)]; } } else { /* Static mapping without port */ next_worker_index = value0.value; } /* Add to translated packets worker lookup */ kv0.value = next_worker_index; clib_bihash_add_del_8_8 (&sm->worker_by_out, &kv0, 1); } else next_worker_index = value0.value; if (PREDICT_FALSE (next_worker_index != cpu_index)) { do_handoff = 1; if (next_worker_index != current_worker_index) { if (hf) hf->n_vectors = VLIB_FRAME_SIZE - n_left_to_next_worker; hf = vlib_get_worker_handoff_queue_elt (sm->fq_out2in_index, next_worker_index, handoff_queue_elt_by_worker_index); n_left_to_next_worker = VLIB_FRAME_SIZE - hf->n_vectors; to_next_worker = &hf->buffer_index[hf->n_vectors]; current_worker_index = next_worker_index; } /* enqueue to correct worker thread */ to_next_worker[0] = bi0; to_next_worker++; n_left_to_next_worker--; if (n_left_to_next_worker == 0) { hf->n_vectors = VLIB_FRAME_SIZE; vlib_put_frame_queue_elt (hf); current_worker_index = ~0; handoff_queue_elt_by_worker_index[next_worker_index] = 0; hf = 0; } } else { do_handoff = 0; /* if this is 1st frame */ if (!f) { f = vlib_get_frame_to_node (vm, snat_out2in_node.index); to_next = vlib_frame_vector_args (f); } to_next[0] = bi0; to_next += 1; f->n_vectors++; } if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { snat_out2in_worker_handoff_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->next_worker_index = next_worker_index; t->do_handoff = do_handoff; } } if (f) vlib_put_frame_to_node (vm, snat_out2in_node.index, f); if (hf) hf->n_vectors = VLIB_FRAME_SIZE - n_left_to_next_worker; /* Ship frames to the worker nodes */ for (i = 0; i < vec_len (handoff_queue_elt_by_worker_index); i++) { if (handoff_queue_elt_by_worker_index[i]) { hf = handoff_queue_elt_by_worker_index[i]; /* * It works better to let the handoff node * rate-adapt, always ship the handoff queue element. */ if (1 || hf->n_vectors == hf->last_n_vectors) { vlib_put_frame_queue_elt (hf); handoff_queue_elt_by_worker_index[i] = 0; } else hf->last_n_vectors = hf->n_vectors; } congested_handoff_queue_by_worker_index[i] = (vlib_frame_queue_t *) (~0); } hf = 0; current_worker_index = ~0; return frame->n_vectors; } VLIB_REGISTER_NODE (snat_out2in_worker_handoff_node) = { .function = snat_out2in_worker_handoff_fn, .name = "snat-out2in-worker-handoff", .vector_size = sizeof (u32), .format_trace = format_snat_out2in_worker_handoff_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_next_nodes = 1, .next_nodes = { [0] = "error-drop", }, }; VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_worker_handoff_node, snat_out2in_worker_handoff_fn); static inline u32 icmp_out2in_fast (snat_main_t *sm, vlib_buffer_t * b0, ip4_header_t * ip0, icmp46_header_t * icmp0, u32 sw_if_index0, vlib_node_runtime_t * node, u32 next0, u32 rx_fib_index0) { snat_session_key_t key0, sm0; icmp_echo_header_t *echo0; u32 new_addr0, old_addr0; u16 old_id0, new_id0; ip_csum_t sum0; snat_runtime_t * rt = (snat_runtime_t *)node->runtime_data; echo0 = (icmp_echo_header_t *)(icmp0+1); key0.addr = ip0->dst_address; key0.port = echo0->identifier; key0.fib_index = rx_fib_index0; if (snat_static_mapping_match(sm, key0, &sm0, 1)) { ip4_address_t * first_int_addr; if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0)) { first_int_addr = ip4_interface_first_address (sm->ip4_main, sw_if_index0, 0 /* just want the address */); rt->cached_sw_if_index = sw_if_index0; if (first_int_addr) rt->cached_ip4_address = first_int_addr->as_u32; else rt->cached_ip4_address = 0; } /* Don't NAT packet aimed at the intfc address */ if (PREDICT_FALSE(ip0->dst_address.as_u32 == rt->cached_ip4_address)) return next0; b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; return SNAT_OUT2IN_NEXT_DROP; } new_addr0 = sm0.addr.as_u32; new_id0 = sm0.port; vnet_buffer(b0)->sw_if_index[VLIB_TX] = sm0.fib_index; old_addr0 = ip0->dst_address.as_u32; ip0->dst_address.as_u32 = new_addr0; sum0 = ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); ip0->checksum = ip_csum_fold (sum0); if (PREDICT_FALSE(new_id0 != echo0->identifier)) { old_id0 = echo0->identifier; echo0->identifier = new_id0; sum0 = icmp0->checksum; sum0 = ip_csum_update (sum0, old_id0, new_id0, icmp_echo_header_t, identifier); icmp0->checksum = ip_csum_fold (sum0); } return next0; } static uword snat_out2in_fast_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_left_from, * from, * to_next; snat_out2in_next_t next_index; u32 pkts_processed = 0; snat_main_t * sm = &snat_main; from = vlib_frame_vector_args (frame); n_left_from = frame->n_vectors; next_index = node->cached_next_index; while (n_left_from > 0) { u32 n_left_to_next; vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (n_left_from > 0 && n_left_to_next > 0) { u32 bi0; vlib_buffer_t * b0; u32 next0 = SNAT_OUT2IN_NEXT_DROP; u32 sw_if_index0; ip4_header_t * ip0; ip_csum_t sum0; u32 new_addr0, old_addr0; u16 new_port0, old_port0; udp_header_t * udp0; tcp_header_t * tcp0; icmp46_header_t * icmp0; snat_session_key_t key0, sm0; u32 proto0; u32 rx_fib_index0; /* speculatively enqueue b0 to the current next frame */ bi0 = from[0]; to_next[0] = bi0; from += 1; to_next += 1; n_left_from -= 1; n_left_to_next -= 1; b0 = vlib_get_buffer (vm, bi0); ip0 = vlib_buffer_get_current (b0); udp0 = ip4_next_header (ip0); tcp0 = (tcp_header_t *) udp0; icmp0 = (icmp46_header_t *) udp0; sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX]; rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index(sw_if_index0); vnet_feature_next (sw_if_index0, &next0, b0); proto0 = ip_proto_to_snat_proto (ip0->protocol); if (PREDICT_FALSE (proto0 == ~0)) goto trace00; if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP)) { next0 = icmp_out2in_fast (sm, b0, ip0, icmp0, sw_if_index0, node, next0, rx_fib_index0); goto trace00; } key0.addr = ip0->dst_address; key0.port = udp0->dst_port; key0.fib_index = rx_fib_index0; if (snat_static_mapping_match(sm, key0, &sm0, 1)) { b0->error = node->errors[SNAT_OUT2IN_ERROR_NO_TRANSLATION]; goto trace00; } new_addr0 = sm0.addr.as_u32; new_port0 = sm0.port; vnet_buffer(b0)->sw_if_index[VLIB_TX] = sm0.fib_index; old_addr0 = ip0->dst_address.as_u32; ip0->dst_address.as_u32 = new_addr0; sum0 = ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); ip0->checksum = ip_csum_fold (sum0); if (PREDICT_FALSE(new_port0 != udp0->dst_port)) { if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP)) { old_port0 = tcp0->ports.dst; tcp0->ports.dst = new_port0; sum0 = tcp0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t /* cheat */, length /* changed member */); tcp0->checksum = ip_csum_fold(sum0); } else { old_port0 = udp0->dst_port; udp0->dst_port = new_port0; udp0->checksum = 0; } } else { if (PREDICT_TRUE(proto0 == SNAT_PROTOCOL_TCP)) { sum0 = tcp0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */); tcp0->checksum = ip_csum_fold(sum0); } } trace00: if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { snat_out2in_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->sw_if_index = sw_if_index0; t->next_index = next0; } pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP; /* verify speculative enqueue, maybe switch current next frame */ vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, bi0, next0); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } vlib_node_increment_counter (vm, snat_out2in_fast_node.index, SNAT_OUT2IN_ERROR_OUT2IN_PACKETS, pkts_processed); return frame->n_vectors; } VLIB_REGISTER_NODE (snat_out2in_fast_node) = { .function = snat_out2in_fast_node_fn, .name = "snat-out2in-fast", .vector_size = sizeof (u32), .format_trace = format_snat_out2in_fast_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN(snat_out2in_error_strings), .error_strings = snat_out2in_error_strings, .runtime_data_bytes = sizeof (snat_runtime_t), .n_next_nodes = SNAT_OUT2IN_N_NEXT, /* edit / add dispositions here */ .next_nodes = { [SNAT_OUT2IN_NEXT_LOOKUP] = "ip4-lookup", [SNAT_OUT2IN_NEXT_DROP] = "error-drop", [SNAT_OUT2IN_NEXT_ICMP_ERROR] = "ip4-icmp-error", }, }; VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_fast_node, snat_out2in_fast_node_fn);