/* * 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 NAT66 inside to outside network translation */ #include <nat/nat66.h> #include <vnet/ip/ip6_to_ip4.h> #include <vnet/fib/fib_table.h> typedef struct { u32 sw_if_index; u32 next_index; } nat66_in2out_trace_t; static u8 * format_nat66_in2out_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 *); nat66_in2out_trace_t *t = va_arg (*args, nat66_in2out_trace_t *); s = format (s, "NAT66-in2out: sw_if_index %d, next index %d", t->sw_if_index, t->next_index); return s; } vlib_node_registration_t nat66_in2out_node; #define foreach_nat66_in2out_error \ _(IN2OUT_PACKETS, "good in2out packets processed") \ _(NO_TRANSLATION, "no translation") \ _(UNKNOWN, "unknown") typedef enum { #define _(sym,str) NAT66_IN2OUT_ERROR_##sym, foreach_nat66_in2out_error #undef _ NAT66_IN2OUT_N_ERROR, } nat66_in2out_error_t; static char *nat66_in2out_error_strings[] = { #define _(sym,string) string, foreach_nat66_in2out_error #undef _ }; typedef enum { NAT66_IN2OUT_NEXT_IP6_LOOKUP, NAT66_IN2OUT_NEXT_DROP, NAT66_IN2OUT_N_NEXT, } nat66_in2out_next_t; static inline u8 nat66_not_translate (u32 rx_fib_index, ip6_address_t ip6_addr) { nat66_main_t *nm = &nat66_main; u32 sw_if_index; snat_interface_t *i; fib_node_index_t fei = FIB_NODE_INDEX_INVALID; fib_prefix_t pfx = { .fp_proto = FIB_PROTOCOL_IP6, .fp_len = 128, .fp_addr = { .ip6 = ip6_addr, }, }; fei = fib_table_lookup (rx_fib_index, &pfx); if (FIB_NODE_INDEX_INVALID == fei) return 1; sw_if_index = fib_entry_get_resolving_interface (fei); if (sw_if_index == ~0) { fei = fib_table_lookup (nm->outside_fib_index, &pfx); if (FIB_NODE_INDEX_INVALID == fei) return 1; sw_if_index = fib_entry_get_resolving_interface (fei); } /* *INDENT-OFF* */ pool_foreach (i, nm->interfaces, ({ /* NAT packet aimed at outside interface */ if (nat_interface_is_outside (i) && sw_if_index == i->sw_if_index) return 0; })); /* *INDENT-ON* */ return 1; } static inline uword nat66_in2out_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_left_from, *from, *to_next; nat66_in2out_next_t next_index; u32 pkts_processed = 0; u32 thread_index = vm->thread_index; nat66_main_t *nm = &nat66_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 = NAT66_IN2OUT_NEXT_IP6_LOOKUP; ip6_header_t *ip60; u16 l4_offset0, frag_offset0; u8 l4_protocol0; nat66_static_mapping_t *sm0; u32 sw_if_index0, fib_index0; udp_header_t *udp0; tcp_header_t *tcp0; icmp46_header_t *icmp0; u16 *checksum0 = 0; ip_csum_t csum0; /* 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); ip60 = vlib_buffer_get_current (b0); if (PREDICT_FALSE (ip6_parse (ip60, b0->current_length, &l4_protocol0, &l4_offset0, &frag_offset0))) { next0 = NAT66_IN2OUT_NEXT_DROP; b0->error = node->errors[NAT66_IN2OUT_ERROR_UNKNOWN]; goto trace0; } sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX]; fib_index0 = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP6, sw_if_index0); if (nat66_not_translate (fib_index0, ip60->dst_address)) goto trace0; sm0 = nat66_static_mapping_get (&ip60->src_address, fib_index0, 1); if (PREDICT_FALSE (!sm0)) { goto trace0; } if (l4_protocol0 == IP_PROTOCOL_UDP) { udp0 = (udp_header_t *) u8_ptr_add (ip60, l4_offset0); checksum0 = &udp0->checksum; } else if (l4_protocol0 == IP_PROTOCOL_TCP) { tcp0 = (tcp_header_t *) u8_ptr_add (ip60, l4_offset0); checksum0 = &tcp0->checksum; } else if (l4_protocol0 == IP_PROTOCOL_ICMP6) { icmp0 = (icmp46_header_t *) u8_ptr_add (ip60, l4_offset0); checksum0 = &icmp0->checksum; } else goto skip_csum0; csum0 = ip_csum_sub_even (*checksum0, ip60->src_address.as_u64[0]); csum0 = ip_csum_sub_even (csum0, ip60->src_address.as_u64[1]); csum0 = ip_csum_add_even (csum0, sm0->e_addr.as_u64[0]); csum0 = ip_csum_add_even (csum0, sm0->e_addr.as_u64[1]); *checksum0 = ip_csum_fold (csum0); skip_csum0: ip60->src_address.as_u64[0] = sm0->e_addr.as_u64[0]; ip60->src_address.as_u64[1] = sm0->e_addr.as_u64[1]; vlib_increment_combined_counter (&nm->session_counters, thread_index, sm0 - nm->sm, 1, vlib_buffer_length_in_chain (vm, b0)); trace0: if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { nat66_in2out_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX]; t->next_index = next0; } pkts_processed += next0 != NAT66_IN2OUT_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, nat66_in2out_node.index, NAT66_IN2OUT_ERROR_IN2OUT_PACKETS, pkts_processed); return frame->n_vectors; } /* *INDENT-OFF* */ VLIB_REGISTER_NODE (nat66_in2out_node) = { .function = nat66_in2out_node_fn, .name = "nat66-in2out", .vector_size = sizeof (u32), .format_trace = format_nat66_in2out_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN (nat66_in2out_error_strings), .error_strings = nat66_in2out_error_strings, .n_next_nodes = NAT66_IN2OUT_N_NEXT, /* edit / add dispositions here */ .next_nodes = { [NAT66_IN2OUT_NEXT_DROP] = "error-drop", [NAT66_IN2OUT_NEXT_IP6_LOOKUP] = "ip6-lookup", }, }; /* *INDENT-ON* */ VLIB_NODE_FUNCTION_MULTIARCH (nat66_in2out_node, nat66_in2out_node_fn); /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */