/* * 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 typedef struct { u32 sw_if_index; u32 next_index; u32 session_index; } snat_out2in_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; } vlib_node_registration_t snat_out2in_node; vlib_node_registration_t snat_out2in_fast_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_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) { 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->users, u); memset (u, 0, sizeof (*u)); u->addr = in2out.addr; pool_get (sm->list_pool, per_user_list_head_elt); u->sessions_per_user_list_head_index = per_user_list_head_elt - sm->list_pool; clib_dlist_init (sm->list_pool, u->sessions_per_user_list_head_index); kv0.value = u - sm->users; /* add user */ clib_bihash_add_del_8_8 (&sm->user_hash, &kv0, 1 /* is_add */); } else { u = pool_elt_at_index (sm->users, value0.value); } pool_get (sm->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->list_pool, per_user_translation_list_elt); clib_dlist_init (sm->list_pool, per_user_translation_list_elt - sm->list_pool); per_user_translation_list_elt->value = s - sm->sessions; s->per_user_index = per_user_translation_list_elt - sm->list_pool; s->per_user_list_head_index = u->sessions_per_user_list_head_index; clib_dlist_addtail (sm->list_pool, s->per_user_list_head_index, per_user_translation_list_elt - sm->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->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->sessions; if (clib_bihash_add_del_8_8 (&sm->out2in, &kv0, 1 /* is_add */)) clib_warning ("out2in key add failed"); return s; } 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) { snat_session_key_t key0, sm0; icmp_echo_header_t *echo0; clib_bihash_kv_8_8_t kv0, value0; snat_session_t * s0; 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.protocol = SNAT_PROTOCOL_ICMP; 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)) { 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; rt->cached_ip4_address = first_int_addr->as_u32; } /* 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; } /* Create session initiated by host from external network */ s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node); if (!s0) return SNAT_OUT2IN_NEXT_DROP; } else s0 = pool_elt_at_index (sm->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); 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); icmp0->checksum = ip_csum_fold (sum0); /* 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->list_pool, s0->per_user_index); clib_dlist_addtail (sm->list_pool, s0->per_user_list_head_index, s0->per_user_index); } 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; ip_lookup_main_t * lm = sm->ip4_lookup_main; ip_config_main_t * cm = &lm->feature_config_mains[VNET_IP_RX_UNICAST_FEAT]; f64 now = vlib_time_now (vm); 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_DROP; u32 next1 = SNAT_OUT2IN_NEXT_DROP; 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); vnet_get_config_data (&cm->config_main, &b0->current_config_index, &next0, 0 /* sizeof config data */); proto0 = ~0; proto0 = (ip0->protocol == IP_PROTOCOL_UDP) ? SNAT_PROTOCOL_UDP : proto0; proto0 = (ip0->protocol == IP_PROTOCOL_TCP) ? SNAT_PROTOCOL_TCP : proto0; proto0 = (ip0->protocol == IP_PROTOCOL_ICMP) ? SNAT_PROTOCOL_ICMP : proto0; if (PREDICT_FALSE (proto0 == ~0)) 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); 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]; goto trace0; } /* Create session initiated by host from external network */ s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node); if (!s0) goto trace0; } else s0 = pool_elt_at_index (sm->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->list_pool, s0->per_user_index); clib_dlist_addtail (sm->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->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); vnet_get_config_data (&cm->config_main, &b1->current_config_index, &next1, 0 /* sizeof config data */); proto1 = ~0; proto1 = (ip1->protocol == IP_PROTOCOL_UDP) ? SNAT_PROTOCOL_UDP : proto1; proto1 = (ip1->protocol == IP_PROTOCOL_TCP) ? SNAT_PROTOCOL_TCP : proto1; proto1 = (ip1->protocol == IP_PROTOCOL_ICMP) ? SNAT_PROTOCOL_ICMP : proto1; if (PREDICT_FALSE (proto1 == ~0)) 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); 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]; goto trace1; } /* Create session initiated by host from external network */ s1 = create_session_for_static_mapping(sm, b1, sm1, key1, node); if (!s1) goto trace1; } else s1 = pool_elt_at_index (sm->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->list_pool, s1->per_user_index); clib_dlist_addtail (sm->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->sessions; } pkts_processed += next0 != SNAT_OUT2IN_NEXT_DROP; 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_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 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); vnet_get_config_data (&cm->config_main, &b0->current_config_index, &next0, 0 /* sizeof config data */); proto0 = ~0; proto0 = (ip0->protocol == IP_PROTOCOL_UDP) ? SNAT_PROTOCOL_UDP : proto0; proto0 = (ip0->protocol == IP_PROTOCOL_TCP) ? SNAT_PROTOCOL_TCP : proto0; proto0 = (ip0->protocol == IP_PROTOCOL_ICMP) ? SNAT_PROTOCOL_ICMP : proto0; if (PREDICT_FALSE (proto0 == ~0)) 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); 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]; goto trace00; } /* Create session initiated by host from external network */ s0 = create_session_for_static_mapping(sm, b0, sm0, key0, node); if (!s0) goto trace00; } else s0 = pool_elt_at_index (sm->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->list_pool, s0->per_user_index); clib_dlist_addtail (sm->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->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", }, }; VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_node, snat_out2in_node_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; rt->cached_ip4_address = first_int_addr->as_u32; } /* 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; ip_lookup_main_t * lm = sm->ip4_lookup_main; ip_config_main_t * cm = &lm->feature_config_mains[VNET_IP_RX_UNICAST_FEAT]; 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_get_config_data (&cm->config_main, &b0->current_config_index, &next0, 0 /* sizeof config data */); proto0 = ~0; proto0 = (ip0->protocol == IP_PROTOCOL_UDP) ? SNAT_PROTOCOL_UDP : proto0; proto0 = (ip0->protocol == IP_PROTOCOL_TCP) ? SNAT_PROTOCOL_TCP : proto0; proto0 = (ip0->protocol == IP_PROTOCOL_ICMP) ? SNAT_PROTOCOL_ICMP : proto0; 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_DROP] = "error-drop", }, }; VLIB_NODE_FUNCTION_MULTIARCH (snat_out2in_fast_node, snat_out2in_fast_node_fn);