/* * 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. */ /** * @brief The NAT inline functions */ #ifndef __included_nat_inlines_h__ #define __included_nat_inlines_h__ #include #include #include static inline uword nat_pre_node_fn_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame, u32 def_next) { u32 n_left_from, *from, *to_next; u16 next_index; 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 next0, next1; u32 arc_next0, arc_next1; u32 bi0, bi1; vlib_buffer_t *b0, *b1; /* 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); next0 = def_next; next1 = def_next; vnet_feature_next (&arc_next0, b0); vnet_feature_next (&arc_next1, b1); vnet_buffer2 (b0)->nat.arc_next = arc_next0; vnet_buffer2 (b1)->nat.arc_next = arc_next1; if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE))) { if (b0->flags & VLIB_BUFFER_IS_TRACED) { nat_pre_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->next_index = next0; t->arc_next_index = arc_next0; } if (b1->flags & VLIB_BUFFER_IS_TRACED) { nat_pre_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->next_index = next1; t->arc_next_index = arc_next1; } } /* 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 next0; u32 arc_next0; u32 bi0; vlib_buffer_t *b0; /* 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); next0 = def_next; vnet_feature_next (&arc_next0, b0); vnet_buffer2 (b0)->nat.arc_next = arc_next0; if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { nat_pre_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->next_index = next0; t->arc_next_index = arc_next0; } /* 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); } return frame->n_vectors; } always_inline u8 is_interface_addr (snat_main_t * sm, vlib_node_runtime_t * node, u32 sw_if_index0, u32 ip4_addr) { snat_runtime_t *rt = (snat_runtime_t *) node->runtime_data; 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; } if (PREDICT_FALSE (ip4_addr == rt->cached_ip4_address)) return 1; else return 0; } always_inline u8 maximum_sessions_exceeded (snat_main_t * sm, u32 thread_index) { if (pool_elts (sm->per_thread_data[thread_index].sessions) >= sm->max_translations) return 1; return 0; } always_inline void nat_send_all_to_node (vlib_main_t * vm, u32 * bi_vector, vlib_node_runtime_t * node, vlib_error_t * error, u32 next) { u32 n_left_from, *from, next_index, *to_next, n_left_to_next; from = bi_vector; n_left_from = vec_len (bi_vector); next_index = node->cached_next_index; while (n_left_from > 0) { 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 = to_next[0] = from[0]; from += 1; n_left_from -= 1; to_next += 1; n_left_to_next -= 1; vlib_buffer_t *p0 = vlib_get_buffer (vm, bi0); if (error) p0->error = *error; vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, bi0, next); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } } always_inline void user_session_increment (snat_main_t * sm, snat_user_t * u, u8 is_static) { if (u->nsessions + u->nstaticsessions < sm->max_translations_per_user) { if (is_static) u->nstaticsessions++; else u->nsessions++; } } always_inline void nat44_delete_user_with_no_session (snat_main_t * sm, snat_user_t * u, u32 thread_index) { clib_bihash_kv_8_8_t kv; snat_user_key_t u_key; snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data, thread_index); if (u->nstaticsessions == 0 && u->nsessions == 0) { u_key.addr.as_u32 = u->addr.as_u32; u_key.fib_index = u->fib_index; kv.key = u_key.as_u64; pool_put_index (tsm->list_pool, u->sessions_per_user_list_head_index); pool_put (tsm->users, u); clib_bihash_add_del_8_8 (&tsm->user_hash, &kv, 0); vlib_set_simple_counter (&sm->total_users, thread_index, 0, pool_elts (tsm->users)); } } always_inline void nat44_delete_session (snat_main_t * sm, snat_session_t * ses, u32 thread_index) { snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data, thread_index); clib_bihash_kv_8_8_t kv, value; snat_user_t *u; const snat_user_key_t u_key = { .addr = ses->in2out.addr, .fib_index = ses->in2out.fib_index }; const u8 u_static = snat_is_session_static (ses); clib_dlist_remove (tsm->list_pool, ses->per_user_index); pool_put_index (tsm->list_pool, ses->per_user_index); clib_dlist_remove (tsm->global_lru_pool, ses->global_lru_index); pool_put_index (tsm->global_lru_pool, ses->global_lru_index); pool_put (tsm->sessions, ses); vlib_set_simple_counter (&sm->total_sessions, thread_index, 0, pool_elts (tsm->sessions)); kv.key = u_key.as_u64; if (!clib_bihash_search_8_8 (&tsm->user_hash, &kv, &value)) { u = pool_elt_at_index (tsm->users, value.value); if (u_static) u->nstaticsessions--; else u->nsessions--; nat44_delete_user_with_no_session (sm, u, thread_index); } } always_inline void nat44_ed_delete_session (snat_main_t * sm, snat_session_t * ses, u32 thread_index, int global_lru_delete /* delete from global LRU list */ ) { snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data, thread_index); if (global_lru_delete) { clib_dlist_remove (tsm->global_lru_pool, ses->global_lru_index); } pool_put_index (tsm->global_lru_pool, ses->global_lru_index); pool_put (tsm->sessions, ses); vlib_set_simple_counter (&sm->total_sessions, thread_index, 0, pool_elts (tsm->sessions)); } /** \brief Set TCP session state. @return 1 if session was closed, otherwise 0 */ always_inline int nat44_set_tcp_session_state_i2o (snat_main_t * sm, f64 now, snat_session_t * ses, vlib_buffer_t * b, u32 thread_index) { u8 tcp_flags = vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags; u32 tcp_ack_number = vnet_buffer (b)->ip.reass.tcp_ack_number; u32 tcp_seq_number = vnet_buffer (b)->ip.reass.tcp_seq_number; if ((ses->state == 0) && (tcp_flags & TCP_FLAG_RST)) ses->state = NAT44_SES_RST; if ((ses->state == NAT44_SES_RST) && !(tcp_flags & TCP_FLAG_RST)) ses->state = 0; if ((tcp_flags & TCP_FLAG_ACK) && (ses->state & NAT44_SES_I2O_SYN) && (ses->state & NAT44_SES_O2I_SYN)) ses->state = 0; if (tcp_flags & TCP_FLAG_SYN) ses->state |= NAT44_SES_I2O_SYN; if (tcp_flags & TCP_FLAG_FIN) { ses->i2o_fin_seq = clib_net_to_host_u32 (tcp_seq_number); ses->state |= NAT44_SES_I2O_FIN; } if ((tcp_flags & TCP_FLAG_ACK) && (ses->state & NAT44_SES_O2I_FIN)) { if (clib_net_to_host_u32 (tcp_ack_number) > ses->o2i_fin_seq) { ses->state |= NAT44_SES_O2I_FIN_ACK; if (nat44_is_ses_closed (ses)) { // if session is now closed, save the timestamp ses->tcp_close_timestamp = now + sm->tcp_transitory_timeout; } } } return 0; } always_inline int nat44_set_tcp_session_state_o2i (snat_main_t * sm, f64 now, snat_session_t * ses, u8 tcp_flags, u32 tcp_ack_number, u32 tcp_seq_number, u32 thread_index) { if ((ses->state == 0) && (tcp_flags & TCP_FLAG_RST)) ses->state = NAT44_SES_RST; if ((ses->state == NAT44_SES_RST) && !(tcp_flags & TCP_FLAG_RST)) ses->state = 0; if ((tcp_flags & TCP_FLAG_ACK) && (ses->state & NAT44_SES_I2O_SYN) && (ses->state & NAT44_SES_O2I_SYN)) ses->state = 0; if (tcp_flags & TCP_FLAG_SYN) ses->state |= NAT44_SES_O2I_SYN; if (tcp_flags & TCP_FLAG_FIN) { ses->o2i_fin_seq = clib_net_to_host_u32 (tcp_seq_number); ses->state |= NAT44_SES_O2I_FIN; } if ((tcp_flags & TCP_FLAG_ACK) && (ses->state & NAT44_SES_I2O_FIN)) { if (clib_net_to_host_u32 (tcp_ack_number) > ses->i2o_fin_seq) ses->state |= NAT44_SES_I2O_FIN_ACK; if (nat44_is_ses_closed (ses)) { // if session is now closed, save the timestamp ses->tcp_close_timestamp = now + sm->tcp_transitory_timeout; } } return 0; } always_inline u32 nat44_session_get_timeout (snat_main_t * sm, snat_session_t * s) { switch (s->in2out.protocol) { case NAT_PROTOCOL_ICMP: return sm->icmp_timeout; case NAT_PROTOCOL_UDP: return sm->udp_timeout; case NAT_PROTOCOL_TCP: { if (s->state) return sm->tcp_transitory_timeout; else return sm->tcp_established_timeout; } default: return sm->udp_timeout; } return 0; } always_inline void nat44_session_update_counters (snat_session_t * s, f64 now, uword bytes, u32 thread_index) { s->last_heard = now; s->total_pkts++; s->total_bytes += bytes; nat_ha_sref (&s->out2in.addr, s->out2in.port, &s->ext_host_addr, s->ext_host_port, s->out2in.protocol, s->out2in.fib_index, s->total_pkts, s->total_bytes, thread_index, &s->ha_last_refreshed, now); } /** \brief Per-user LRU list maintenance */ always_inline void nat44_session_update_lru (snat_main_t * sm, snat_session_t * s, u32 thread_index) { /* don't update too often - timeout is in a magnitude of seconds anyway */ if (s->last_heard > s->last_lru_update + 1) { if (!sm->endpoint_dependent) { clib_dlist_remove (sm->per_thread_data[thread_index].list_pool, s->per_user_index); clib_dlist_addtail (sm->per_thread_data[thread_index].list_pool, s->per_user_list_head_index, s->per_user_index); } clib_dlist_remove (sm->per_thread_data[thread_index].global_lru_pool, s->global_lru_index); clib_dlist_addtail (sm->per_thread_data[thread_index].global_lru_pool, sm-> per_thread_data[thread_index].global_lru_head_index, s->global_lru_index); s->last_lru_update = s->last_heard; } } always_inline void make_ed_kv (ip4_address_t * l_addr, ip4_address_t * r_addr, u8 proto, u32 fib_index, u16 l_port, u16 r_port, u64 value, clib_bihash_kv_16_8_t * kv) { kv->key[0] = (u64) r_addr->as_u32 << 32 | l_addr->as_u32; kv->key[1] = (u64) r_port << 48 | (u64) l_port << 32 | fib_index << 8 | proto; kv->value = value; } always_inline void split_ed_kv (clib_bihash_kv_16_8_t * kv, ip4_address_t * l_addr, ip4_address_t * r_addr, u8 * proto, u32 * fib_index, u16 * l_port, u16 * r_port) { if (l_addr) { l_addr->as_u32 = kv->key[0] & (u32) ~ 0; } if (r_addr) { r_addr->as_u32 = kv->key[0] >> 32; } if (r_port) { *r_port = kv->key[1] >> 48; } if (l_port) { *l_port = (kv->key[1] >> 32) & (u16) ~ 0; } if (fib_index) { *fib_index = (kv->key[1] >> 8) & ((1 << 24) - 1); } if (proto) { *proto = kv->key[1] & (u8) ~ 0; } } always_inline void make_sm_kv (clib_bihash_kv_8_8_t * kv, ip4_address_t * addr, u8 proto, u32 fib_index, u16 port) { kv->key = (u64) fib_index << 51 | (u64) proto << 48 | (u64) port << 32 | addr->as_u32; kv->value = ~0ULL; } static_always_inline int get_icmp_i2o_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index, u64 value, u8 * nat_proto, u16 * l_port, u16 * r_port, clib_bihash_kv_16_8_t * kv) { u8 proto; u16 _l_port, _r_port; ip4_address_t *l_addr, *r_addr; icmp46_header_t *icmp0; icmp_echo_header_t *echo0, *inner_echo0 = 0; ip4_header_t *inner_ip0 = 0; void *l4_header = 0; icmp46_header_t *inner_icmp0; icmp0 = (icmp46_header_t *) ip4_next_header (ip0); echo0 = (icmp_echo_header_t *) (icmp0 + 1); if (!icmp_type_is_error_message (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)) { proto = IP_PROTOCOL_ICMP; l_addr = &ip0->src_address; r_addr = &ip0->dst_address; _l_port = vnet_buffer (b)->ip.reass.l4_src_port; // TODO should this be src or dst? _r_port = 0; } else { inner_ip0 = (ip4_header_t *) (echo0 + 1); l4_header = ip4_next_header (inner_ip0); proto = inner_ip0->protocol; r_addr = &inner_ip0->src_address; l_addr = &inner_ip0->dst_address; switch (ip_proto_to_nat_proto (inner_ip0->protocol)) { case NAT_PROTOCOL_ICMP: inner_icmp0 = (icmp46_header_t *) l4_header; inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1); _r_port = 0; _l_port = inner_echo0->identifier; break; case NAT_PROTOCOL_UDP: case NAT_PROTOCOL_TCP: _l_port = ((tcp_udp_header_t *) l4_header)->dst_port; _r_port = ((tcp_udp_header_t *) l4_header)->src_port; break; default: return NAT_IN2OUT_ED_ERROR_UNSUPPORTED_PROTOCOL; } } make_ed_kv (l_addr, r_addr, proto, rx_fib_index, _l_port, _r_port, value, kv); if (nat_proto) { *nat_proto = ip_proto_to_nat_proto (proto); } if (l_port) { *l_port = _l_port; } if (r_port) { *r_port = _r_port; } return 0; } static_always_inline int get_icmp_o2i_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index, u64 value, u8 * nat_proto, u16 * l_port, u16 * r_port, clib_bihash_kv_16_8_t * kv) { icmp46_header_t *icmp0; u8 proto; ip4_address_t *l_addr, *r_addr; u16 _l_port, _r_port; icmp_echo_header_t *echo0, *inner_echo0 = 0; ip4_header_t *inner_ip0; void *l4_header = 0; icmp46_header_t *inner_icmp0; icmp0 = (icmp46_header_t *) ip4_next_header (ip0); echo0 = (icmp_echo_header_t *) (icmp0 + 1); if (!icmp_type_is_error_message (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags)) { proto = IP_PROTOCOL_ICMP; l_addr = &ip0->dst_address; r_addr = &ip0->src_address; _l_port = vnet_buffer (b)->ip.reass.l4_src_port; // TODO should this be src or dst? _r_port = 0; } else { inner_ip0 = (ip4_header_t *) (echo0 + 1); l4_header = ip4_next_header (inner_ip0); proto = inner_ip0->protocol; l_addr = &inner_ip0->src_address; r_addr = &inner_ip0->dst_address; switch (ip_proto_to_nat_proto (inner_ip0->protocol)) { case NAT_PROTOCOL_ICMP: inner_icmp0 = (icmp46_header_t *) l4_header; inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1); _l_port = inner_echo0->identifier; _r_port = 0; break; case NAT_PROTOCOL_UDP: case NAT_PROTOCOL_TCP: _l_port = ((tcp_udp_header_t *) l4_header)->src_port; _r_port = ((tcp_udp_header_t *) l4_header)->dst_port; break; default: return -1; } } make_ed_kv (l_addr, r_addr, proto, rx_fib_index, _l_port, _r_port, value, kv); if (nat_proto) { *nat_proto = ip_proto_to_nat_proto (proto); } if (l_port) { *l_port = _l_port; } if (r_port) { *r_port = _r_port; } return 0; } always_inline void mss_clamping (snat_main_t * sm, tcp_header_t * tcp, ip_csum_t * sum) { u8 *data; u8 opt_len, opts_len, kind; u16 mss; if (!(sm->mss_clamping && tcp_syn (tcp))) return; opts_len = (tcp_doff (tcp) << 2) - sizeof (tcp_header_t); data = (u8 *) (tcp + 1); for (; opts_len > 0; opts_len -= opt_len, data += opt_len) { kind = data[0]; if (kind == TCP_OPTION_EOL) break; else if (kind == TCP_OPTION_NOOP) { opt_len = 1; continue; } else { if (opts_len < 2) return; opt_len = data[1]; if (opt_len < 2 || opt_len > opts_len) return; } if (kind == TCP_OPTION_MSS) { mss = *(u16 *) (data + 2); if (clib_net_to_host_u16 (mss) > sm->mss_clamping) { *sum = ip_csum_update (*sum, mss, sm->mss_value_net, ip4_header_t, length); clib_memcpy_fast (data + 2, &sm->mss_value_net, 2); } return; } } } /** * @brief Check if packet should be translated * * Packets aimed at outside interface and external address with active session * should be translated. * * @param sm NAT main * @param rt NAT runtime data * @param sw_if_index0 index of the inside interface * @param ip0 IPv4 header * @param proto0 NAT protocol * @param rx_fib_index0 RX FIB index * * @returns 0 if packet should be translated otherwise 1 */ static inline int snat_not_translate_fast (snat_main_t * sm, vlib_node_runtime_t * node, u32 sw_if_index0, ip4_header_t * ip0, u32 proto0, u32 rx_fib_index0) { if (sm->out2in_dpo) return 0; fib_node_index_t fei = FIB_NODE_INDEX_INVALID; nat_outside_fib_t *outside_fib; fib_prefix_t pfx = { .fp_proto = FIB_PROTOCOL_IP4, .fp_len = 32, .fp_addr = { .ip4.as_u32 = ip0->dst_address.as_u32, } , }; /* Don't NAT packet aimed at the intfc address */ if (PREDICT_FALSE (is_interface_addr (sm, node, sw_if_index0, ip0->dst_address.as_u32))) return 1; fei = fib_table_lookup (rx_fib_index0, &pfx); if (FIB_NODE_INDEX_INVALID != fei) { u32 sw_if_index = fib_entry_get_resolving_interface (fei); if (sw_if_index == ~0) { vec_foreach (outside_fib, sm->outside_fibs) { fei = fib_table_lookup (outside_fib->fib_index, &pfx); if (FIB_NODE_INDEX_INVALID != fei) { sw_if_index = fib_entry_get_resolving_interface (fei); if (sw_if_index != ~0) break; } } } if (sw_if_index == ~0) return 1; snat_interface_t *i; /* *INDENT-OFF* */ pool_foreach (i, sm->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 void increment_v4_address (ip4_address_t * a) { u32 v; v = clib_net_to_host_u32 (a->as_u32) + 1; a->as_u32 = clib_host_to_net_u32 (v); } #endif /* __included_nat_inlines_h__ */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */