/* * Copyright (c) 2020 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 Deterministic NAT (CGN) inside to outside translation */ #include #include #include #include #include #include #include #include #include #include #include typedef enum { DET44_IN2OUT_NEXT_LOOKUP, DET44_IN2OUT_NEXT_DROP, DET44_IN2OUT_NEXT_ICMP_ERROR, DET44_IN2OUT_N_NEXT, } det44_in2out_next_t; typedef struct { u32 sw_if_index; u32 next_index; u32 session_index; } det44_in2out_trace_t; #define foreach_det44_in2out_error \ _(UNSUPPORTED_PROTOCOL, "Unsupported protocol") \ _(NO_TRANSLATION, "No translation") \ _(BAD_ICMP_TYPE, "unsupported ICMP type") \ _(OUT_OF_PORTS, "Out of ports") \ _(IN2OUT_PACKETS, "Good in2out packets processed") typedef enum { #define _(sym,str) DET44_IN2OUT_ERROR_##sym, foreach_det44_in2out_error #undef _ DET44_IN2OUT_N_ERROR, } det44_in2out_error_t; static char *det44_in2out_error_strings[] = { #define _(sym,string) string, foreach_det44_in2out_error #undef _ }; static u8 * format_det44_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 *); det44_in2out_trace_t *t = va_arg (*args, det44_in2out_trace_t *); s = format (s, "DET44_IN2OUT: sw_if_index %d, next index %d, session %d", t->sw_if_index, t->next_index, t->session_index); return s; } #ifndef CLIB_MARCH_VARIANT /** * Get address and port values to be used for ICMP packet translation * and create session if needed * * @param[in,out] node NAT node runtime * @param[in] thread_index thread index * @param[in,out] b0 buffer containing packet to be translated * @param[in,out] ip0 ip header * @param[out] p_proto protocol used for matching * @param[out] p_value address and port after NAT translation * @param[out] p_dont_translate if packet should not be translated * @param d optional parameter * @param e optional parameter */ u32 icmp_match_in2out_det (vlib_node_runtime_t * node, u32 thread_index, vlib_buffer_t * b0, ip4_header_t * ip0, ip4_address_t * addr, u16 * port, u32 * fib_index, nat_protocol_t * proto, void *d, void *e, u8 * dont_translate) { det44_main_t *dm = &det44_main; vlib_main_t *vm = vlib_get_main (); icmp46_header_t *icmp0; u32 sw_if_index0; u32 rx_fib_index0; nat_protocol_t protocol; snat_det_out_key_t key0; u32 next0 = ~0; icmp_echo_header_t *echo0, *inner_echo0 = 0; ip4_header_t *inner_ip0; void *l4_header = 0; icmp46_header_t *inner_icmp0; snat_det_map_t *mp0 = 0; ip4_address_t new_addr0; u16 lo_port0, i0; snat_det_session_t *ses0 = 0; ip4_address_t in_addr; u16 in_port; *dont_translate = 0; icmp0 = (icmp46_header_t *) ip4_next_header (ip0); echo0 = (icmp_echo_header_t *) (icmp0 + 1); 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); if (!icmp_type_is_error_message (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags)) { protocol = NAT_PROTOCOL_ICMP; in_addr = ip0->src_address; in_port = vnet_buffer (b0)->ip.reass.l4_src_port; } else { /* if error message, then it's not fragmented and we can access it */ inner_ip0 = (ip4_header_t *) (echo0 + 1); l4_header = ip4_next_header (inner_ip0); protocol = ip_proto_to_nat_proto (inner_ip0->protocol); in_addr = inner_ip0->dst_address; switch (protocol) { case NAT_PROTOCOL_ICMP: inner_icmp0 = (icmp46_header_t *) l4_header; inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1); in_port = inner_echo0->identifier; break; case NAT_PROTOCOL_UDP: case NAT_PROTOCOL_TCP: in_port = ((tcp_udp_header_t *) l4_header)->dst_port; break; default: b0->error = node->errors[DET44_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL]; next0 = DET44_IN2OUT_NEXT_DROP; goto out; } } mp0 = snat_det_map_by_user (&in_addr); if (PREDICT_FALSE (!mp0)) { if (PREDICT_FALSE (det44_translate (node, sw_if_index0, ip0, IP_PROTOCOL_ICMP, rx_fib_index0))) { *dont_translate = 1; goto out; } next0 = DET44_IN2OUT_NEXT_DROP; b0->error = node->errors[DET44_IN2OUT_ERROR_NO_TRANSLATION]; goto out; } snat_det_forward (mp0, &in_addr, &new_addr0, &lo_port0); key0.ext_host_addr = ip0->dst_address; key0.ext_host_port = 0; ses0 = snat_det_find_ses_by_in (mp0, &in_addr, in_port, key0); if (PREDICT_FALSE (!ses0)) { if (PREDICT_FALSE (det44_translate (node, sw_if_index0, ip0, IP_PROTOCOL_ICMP, rx_fib_index0))) { *dont_translate = 1; goto out; } if (icmp0->type != ICMP4_echo_request) { b0->error = node->errors[DET44_IN2OUT_ERROR_BAD_ICMP_TYPE]; next0 = DET44_IN2OUT_NEXT_DROP; goto out; } for (i0 = 0; i0 < mp0->ports_per_host; i0++) { key0.out_port = clib_host_to_net_u16 (lo_port0 + ((i0 + clib_net_to_host_u16 (echo0->identifier)) % mp0->ports_per_host)); if (snat_det_get_ses_by_out (mp0, &in_addr, key0.as_u64)) continue; ses0 = snat_det_ses_create (thread_index, mp0, &in_addr, echo0->identifier, &key0); break; } if (PREDICT_FALSE (!ses0)) { next0 = DET44_IN2OUT_NEXT_DROP; b0->error = node->errors[DET44_IN2OUT_ERROR_OUT_OF_PORTS]; goto out; } } if (PREDICT_FALSE (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags != ICMP4_echo_request && !icmp_type_is_error_message (vnet_buffer (b0)->ip. reass.icmp_type_or_tcp_flags))) { b0->error = node->errors[DET44_IN2OUT_ERROR_BAD_ICMP_TYPE]; next0 = DET44_IN2OUT_NEXT_DROP; goto out; } u32 now = (u32) vlib_time_now (vm); ses0->state = DET44_SESSION_ICMP_ACTIVE; ses0->expire = now + dm->timeouts.icmp; out: *proto = protocol; if (ses0) { *addr = new_addr0; *fib_index = dm->outside_fib_index; *port = ses0->out.out_port; } if (d) *(snat_det_session_t **) d = ses0; if (e) *(snat_det_map_t **) e = mp0; return next0; } #endif #ifndef CLIB_MARCH_VARIANT u32 det44_icmp_in2out (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, u32 thread_index, void *d, void *e) { vlib_main_t *vm = vlib_get_main (); u16 old_id0, new_id0, port, checksum0, old_checksum0, new_checksum0; u32 new_addr0, old_addr0, next0_tmp, fib_index; icmp_echo_header_t *echo0, *inner_echo0; icmp46_header_t *inner_icmp0; ip4_header_t *inner_ip0; ip4_address_t addr; void *l4_header; u8 dont_translate; ip_csum_t sum0; nat_protocol_t protocol; echo0 = (icmp_echo_header_t *) (icmp0 + 1); next0_tmp = icmp_match_in2out_det (node, thread_index, b0, ip0, &addr, &port, &fib_index, &protocol, d, e, &dont_translate); if (next0_tmp != ~0) next0 = next0_tmp; if (next0 == DET44_IN2OUT_NEXT_DROP || dont_translate) goto out; if (PREDICT_TRUE (!ip4_is_fragment (ip0))) { sum0 = ip_incremental_checksum_buffer (vm, b0, (u8 *) icmp0 - (u8 *) vlib_buffer_get_current (b0), ntohs (ip0->length) - ip4_header_bytes (ip0), 0); checksum0 = ~ip_csum_fold (sum0); if (PREDICT_FALSE (checksum0 != 0 && checksum0 != 0xffff)) { next0 = DET44_IN2OUT_NEXT_DROP; goto out; } } old_addr0 = ip0->src_address.as_u32; new_addr0 = ip0->src_address.as_u32 = addr.as_u32; sum0 = ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, src_address /* changed member */ ); ip0->checksum = ip_csum_fold (sum0); if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment) { if (icmp0->checksum == 0) icmp0->checksum = 0xffff; if (!icmp_type_is_error_message (icmp0->type)) { new_id0 = port; if (PREDICT_FALSE (new_id0 != echo0->identifier)) { old_id0 = echo0->identifier; new_id0 = 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); } } else { inner_ip0 = (ip4_header_t *) (echo0 + 1); l4_header = ip4_next_header (inner_ip0); if (!ip4_header_checksum_is_valid (inner_ip0)) { next0 = DET44_IN2OUT_NEXT_DROP; goto out; } /* update inner destination IP address */ old_addr0 = inner_ip0->dst_address.as_u32; inner_ip0->dst_address = addr; new_addr0 = inner_ip0->dst_address.as_u32; sum0 = icmp0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */ ); icmp0->checksum = ip_csum_fold (sum0); /* update inner IP header checksum */ old_checksum0 = inner_ip0->checksum; sum0 = inner_ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t, dst_address /* changed member */ ); inner_ip0->checksum = ip_csum_fold (sum0); new_checksum0 = inner_ip0->checksum; sum0 = icmp0->checksum; sum0 = ip_csum_update (sum0, old_checksum0, new_checksum0, ip4_header_t, checksum); icmp0->checksum = ip_csum_fold (sum0); switch (protocol) { case NAT_PROTOCOL_ICMP: inner_icmp0 = (icmp46_header_t *) l4_header; inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1); old_id0 = inner_echo0->identifier; new_id0 = 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 NAT_PROTOCOL_UDP: case NAT_PROTOCOL_TCP: old_id0 = ((tcp_udp_header_t *) l4_header)->dst_port; new_id0 = port; ((tcp_udp_header_t *) l4_header)->dst_port = new_id0; sum0 = icmp0->checksum; sum0 = ip_csum_update (sum0, old_id0, new_id0, tcp_udp_header_t, dst_port); icmp0->checksum = ip_csum_fold (sum0); break; default: ASSERT (0); } } } if (vnet_buffer (b0)->sw_if_index[VLIB_TX] == ~0) vnet_buffer (b0)->sw_if_index[VLIB_TX] = fib_index; out: return next0; } #endif VLIB_NODE_FN (det44_in2out_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_left_from, *from; u32 pkts_processed = 0; det44_main_t *dm = &det44_main; u32 now = (u32) vlib_time_now (vm); u32 thread_index = vm->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 >= 2) { vlib_buffer_t *b0, *b1; u32 next0, next1; u32 sw_if_index0, sw_if_index1; ip4_header_t *ip0, *ip1; ip_csum_t sum0, sum1; ip4_address_t new_addr0, old_addr0, new_addr1, old_addr1; u16 old_port0, new_port0, lo_port0, i0; u16 old_port1, new_port1, lo_port1, i1; udp_header_t *udp0, *udp1; tcp_header_t *tcp0, *tcp1; u32 proto0, proto1; snat_det_out_key_t key0, key1; snat_det_map_t *mp0, *mp1; snat_det_session_t *ses0 = 0, *ses1 = 0; u32 rx_fib_index0, rx_fib_index1; icmp46_header_t *icmp0, *icmp1; b0 = *b; b++; b1 = *b; b++; /* Prefetch next iteration. */ if (PREDICT_TRUE (n_left_from >= 4)) { vlib_buffer_t *p2, *p3; p2 = *b; p3 = *(b + 1); vlib_prefetch_buffer_header (p2, LOAD); vlib_prefetch_buffer_header (p3, LOAD); clib_prefetch_load (p2->data); clib_prefetch_load (p3->data); } next0 = DET44_IN2OUT_NEXT_LOOKUP; next1 = DET44_IN2OUT_NEXT_LOOKUP; ip0 = vlib_buffer_get_current (b0); udp0 = ip4_next_header (ip0); tcp0 = (tcp_header_t *) udp0; sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX]; 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 = DET44_IN2OUT_NEXT_ICMP_ERROR; goto trace0; } proto0 = ip_proto_to_nat_proto (ip0->protocol); if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP)) { rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0); icmp0 = (icmp46_header_t *) udp0; // TODO: next0 = det44_icmp_in2out (b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, next0, thread_index, &ses0, &mp0); goto trace0; } mp0 = snat_det_map_by_user (&ip0->src_address); if (PREDICT_FALSE (!mp0)) { det44_log_info ("no match for internal host %U", format_ip4_address, &ip0->src_address); next0 = DET44_IN2OUT_NEXT_DROP; b0->error = node->errors[DET44_IN2OUT_ERROR_NO_TRANSLATION]; goto trace0; } snat_det_forward (mp0, &ip0->src_address, &new_addr0, &lo_port0); key0.ext_host_addr = ip0->dst_address; key0.ext_host_port = tcp0->dst; ses0 = snat_det_find_ses_by_in (mp0, &ip0->src_address, tcp0->src, key0); if (PREDICT_FALSE (!ses0)) { for (i0 = 0; i0 < mp0->ports_per_host; i0++) { key0.out_port = clib_host_to_net_u16 (lo_port0 + ((i0 + clib_net_to_host_u16 (tcp0->src)) % mp0->ports_per_host)); if (snat_det_get_ses_by_out (mp0, &ip0->src_address, key0.as_u64)) continue; ses0 = snat_det_ses_create (thread_index, mp0, &ip0->src_address, tcp0->src, &key0); break; } if (PREDICT_FALSE (!ses0)) { /* too many sessions for user, send ICMP error packet */ vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; icmp4_error_set_vnet_buffer (b0, ICMP4_destination_unreachable, ICMP4_destination_unreachable_destination_unreachable_host, 0); next0 = DET44_IN2OUT_NEXT_ICMP_ERROR; goto trace0; } } old_port0 = udp0->src_port; udp0->src_port = new_port0 = ses0->out.out_port; old_addr0.as_u32 = ip0->src_address.as_u32; ip0->src_address.as_u32 = new_addr0.as_u32; vnet_buffer (b0)->sw_if_index[VLIB_TX] = dm->outside_fib_index; sum0 = ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0.as_u32, new_addr0.as_u32, ip4_header_t, src_address /* changed member */ ); ip0->checksum = ip_csum_fold (sum0); if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP)) { if (tcp0->flags & TCP_FLAG_SYN) ses0->state = DET44_SESSION_TCP_SYN_SENT; else if (tcp0->flags & TCP_FLAG_ACK && ses0->state == DET44_SESSION_TCP_SYN_SENT) ses0->state = DET44_SESSION_TCP_ESTABLISHED; else if (tcp0->flags & TCP_FLAG_FIN && ses0->state == DET44_SESSION_TCP_ESTABLISHED) ses0->state = DET44_SESSION_TCP_FIN_WAIT; else if (tcp0->flags & TCP_FLAG_ACK && ses0->state == DET44_SESSION_TCP_FIN_WAIT) snat_det_ses_close (mp0, ses0); else if (tcp0->flags & TCP_FLAG_FIN && ses0->state == DET44_SESSION_TCP_CLOSE_WAIT) ses0->state = DET44_SESSION_TCP_LAST_ACK; else if (tcp0->flags == 0 && ses0->state == DET44_SESSION_UNKNOWN) ses0->state = DET44_SESSION_TCP_ESTABLISHED; sum0 = tcp0->checksum; sum0 = ip_csum_update (sum0, old_addr0.as_u32, new_addr0.as_u32, ip4_header_t, dst_address /* changed member */ ); sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t /* cheat */ , length /* changed member */ ); mss_clamping (dm->mss_clamping, tcp0, &sum0); tcp0->checksum = ip_csum_fold (sum0); } else { ses0->state = DET44_SESSION_UDP_ACTIVE; if (PREDICT_FALSE (udp0->checksum)) { sum0 = udp0->checksum; sum0 = ip_csum_update (sum0, old_addr0.as_u32, new_addr0.as_u32, ip4_header_t, dst_address /* changed member */ ); sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t /* cheat */ , length /* changed member */ ); udp0->checksum = ip_csum_fold (sum0); } } switch (ses0->state) { case DET44_SESSION_UDP_ACTIVE: ses0->expire = now + dm->timeouts.udp; break; case DET44_SESSION_TCP_SYN_SENT: case DET44_SESSION_TCP_FIN_WAIT: case DET44_SESSION_TCP_CLOSE_WAIT: case DET44_SESSION_TCP_LAST_ACK: ses0->expire = now + dm->timeouts.tcp.transitory; break; case DET44_SESSION_TCP_ESTABLISHED: ses0->expire = now + dm->timeouts.tcp.established; break; } trace0: if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { det44_in2out_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 (ses0) t->session_index = ses0 - mp0->sessions; } pkts_processed += next0 != DET44_IN2OUT_NEXT_DROP; ip1 = vlib_buffer_get_current (b1); udp1 = ip4_next_header (ip1); tcp1 = (tcp_header_t *) udp1; sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX]; if (PREDICT_FALSE (ip1->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); next1 = DET44_IN2OUT_NEXT_ICMP_ERROR; goto trace1; } proto1 = ip_proto_to_nat_proto (ip1->protocol); if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP)) { rx_fib_index1 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index1); icmp1 = (icmp46_header_t *) udp1; next1 = det44_icmp_in2out (b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node, next1, thread_index, &ses1, &mp1); goto trace1; } mp1 = snat_det_map_by_user (&ip1->src_address); if (PREDICT_FALSE (!mp1)) { det44_log_info ("no match for internal host %U", format_ip4_address, &ip0->src_address); next1 = DET44_IN2OUT_NEXT_DROP; b1->error = node->errors[DET44_IN2OUT_ERROR_NO_TRANSLATION]; goto trace1; } snat_det_forward (mp1, &ip1->src_address, &new_addr1, &lo_port1); key1.ext_host_addr = ip1->dst_address; key1.ext_host_port = tcp1->dst; ses1 = snat_det_find_ses_by_in (mp1, &ip1->src_address, tcp1->src, key1); if (PREDICT_FALSE (!ses1)) { for (i1 = 0; i1 < mp1->ports_per_host; i1++) { key1.out_port = clib_host_to_net_u16 (lo_port1 + ((i1 + clib_net_to_host_u16 (tcp1->src)) % mp1->ports_per_host)); if (snat_det_get_ses_by_out (mp1, &ip1->src_address, key1.as_u64)) continue; ses1 = snat_det_ses_create (thread_index, mp1, &ip1->src_address, tcp1->src, &key1); break; } if (PREDICT_FALSE (!ses1)) { /* too many sessions for user, send ICMP error packet */ vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0; icmp4_error_set_vnet_buffer (b1, ICMP4_destination_unreachable, ICMP4_destination_unreachable_destination_unreachable_host, 0); next1 = DET44_IN2OUT_NEXT_ICMP_ERROR; goto trace1; } } old_port1 = udp1->src_port; udp1->src_port = new_port1 = ses1->out.out_port; old_addr1.as_u32 = ip1->src_address.as_u32; ip1->src_address.as_u32 = new_addr1.as_u32; vnet_buffer (b1)->sw_if_index[VLIB_TX] = dm->outside_fib_index; sum1 = ip1->checksum; sum1 = ip_csum_update (sum1, old_addr1.as_u32, new_addr1.as_u32, ip4_header_t, src_address /* changed member */ ); ip1->checksum = ip_csum_fold (sum1); if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP)) { if (tcp1->flags & TCP_FLAG_SYN) ses1->state = DET44_SESSION_TCP_SYN_SENT; else if (tcp1->flags & TCP_FLAG_ACK && ses1->state == DET44_SESSION_TCP_SYN_SENT) ses1->state = DET44_SESSION_TCP_ESTABLISHED; else if (tcp1->flags & TCP_FLAG_FIN && ses1->state == DET44_SESSION_TCP_ESTABLISHED) ses1->state = DET44_SESSION_TCP_FIN_WAIT; else if (tcp1->flags & TCP_FLAG_ACK && ses1->state == DET44_SESSION_TCP_FIN_WAIT) snat_det_ses_close (mp1, ses1); else if (tcp1->flags & TCP_FLAG_FIN && ses1->state == DET44_SESSION_TCP_CLOSE_WAIT) ses1->state = DET44_SESSION_TCP_LAST_ACK; else if (tcp1->flags == 0 && ses1->state == DET44_SESSION_UNKNOWN) ses1->state = DET44_SESSION_TCP_ESTABLISHED; sum1 = tcp1->checksum; sum1 = ip_csum_update (sum1, old_addr1.as_u32, new_addr1.as_u32, ip4_header_t, dst_address /* changed member */ ); sum1 = ip_csum_update (sum1, old_port1, new_port1, ip4_header_t /* cheat */ , length /* changed member */ ); mss_clamping (dm->mss_clamping, tcp1, &sum1); tcp1->checksum = ip_csum_fold (sum1); } else { ses1->state = DET44_SESSION_UDP_ACTIVE; if (PREDICT_FALSE (udp1->checksum)) { sum1 = udp1->checksum; sum1 = ip_csum_update (sum1, old_addr1.as_u32, new_addr1.as_u32, ip4_header_t, dst_address /* changed member */ ); sum1 = ip_csum_update (sum1, old_port1, new_port1, ip4_header_t /* cheat */ , length /* changed member */ ); udp1->checksum = ip_csum_fold (sum1); } } switch (ses1->state) { case DET44_SESSION_UDP_ACTIVE: ses1->expire = now + dm->timeouts.udp; break; case DET44_SESSION_TCP_SYN_SENT: case DET44_SESSION_TCP_FIN_WAIT: case DET44_SESSION_TCP_CLOSE_WAIT: case DET44_SESSION_TCP_LAST_ACK: ses1->expire = now + dm->timeouts.tcp.transitory; break; case DET44_SESSION_TCP_ESTABLISHED: ses1->expire = now + dm->timeouts.tcp.established; break; } trace1: if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b1->flags & VLIB_BUFFER_IS_TRACED))) { det44_in2out_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 (ses1) t->session_index = ses1 - mp1->sessions; } pkts_processed += next1 != DET44_IN2OUT_NEXT_DROP; n_left_from -= 2; next[0] = next0; next[1] = next1; next += 2; } while (n_left_from > 0) { vlib_buffer_t *b0; u32 next0; u32 sw_if_index0; ip4_header_t *ip0; ip_csum_t sum0; ip4_address_t new_addr0, old_addr0; u16 old_port0, new_port0, lo_port0, i0; udp_header_t *udp0; tcp_header_t *tcp0; u32 proto0; snat_det_out_key_t key0; snat_det_map_t *mp0; snat_det_session_t *ses0 = 0; u32 rx_fib_index0; icmp46_header_t *icmp0; b0 = *b; b++; next0 = DET44_IN2OUT_NEXT_LOOKUP; ip0 = vlib_buffer_get_current (b0); udp0 = ip4_next_header (ip0); tcp0 = (tcp_header_t *) udp0; sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX]; 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 = DET44_IN2OUT_NEXT_ICMP_ERROR; goto trace00; } proto0 = ip_proto_to_nat_proto (ip0->protocol); if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP)) { rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0); icmp0 = (icmp46_header_t *) udp0; next0 = det44_icmp_in2out (b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node, next0, thread_index, &ses0, &mp0); goto trace00; } mp0 = snat_det_map_by_user (&ip0->src_address); if (PREDICT_FALSE (!mp0)) { det44_log_info ("no match for internal host %U", format_ip4_address, &ip0->src_address); next0 = DET44_IN2OUT_NEXT_DROP; b0->error = node->errors[DET44_IN2OUT_ERROR_NO_TRANSLATION]; goto trace00; } snat_det_forward (mp0, &ip0->src_address, &new_addr0, &lo_port0); key0.ext_host_addr = ip0->dst_address; key0.ext_host_port = tcp0->dst; ses0 = snat_det_find_ses_by_in (mp0, &ip0->src_address, tcp0->src, key0); if (PREDICT_FALSE (!ses0)) { for (i0 = 0; i0 < mp0->ports_per_host; i0++) { key0.out_port = clib_host_to_net_u16 (lo_port0 + ((i0 + clib_net_to_host_u16 (tcp0->src)) % mp0->ports_per_host)); if (snat_det_get_ses_by_out (mp0, &ip0->src_address, key0.as_u64)) continue; ses0 = snat_det_ses_create (thread_index, mp0, &ip0->src_address, tcp0->src, &key0); break; } if (PREDICT_FALSE (!ses0)) { /* too many sessions for user, send ICMP error packet */ vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; icmp4_error_set_vnet_buffer (b0, ICMP4_destination_unreachable, ICMP4_destination_unreachable_destination_unreachable_host, 0); next0 = DET44_IN2OUT_NEXT_ICMP_ERROR; goto trace00; } } old_port0 = udp0->src_port; udp0->src_port = new_port0 = ses0->out.out_port; old_addr0.as_u32 = ip0->src_address.as_u32; ip0->src_address.as_u32 = new_addr0.as_u32; vnet_buffer (b0)->sw_if_index[VLIB_TX] = dm->outside_fib_index; sum0 = ip0->checksum; sum0 = ip_csum_update (sum0, old_addr0.as_u32, new_addr0.as_u32, ip4_header_t, src_address /* changed member */ ); ip0->checksum = ip_csum_fold (sum0); if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP)) { if (tcp0->flags & TCP_FLAG_SYN) ses0->state = DET44_SESSION_TCP_SYN_SENT; else if (tcp0->flags & TCP_FLAG_ACK && ses0->state == DET44_SESSION_TCP_SYN_SENT) ses0->state = DET44_SESSION_TCP_ESTABLISHED; else if (tcp0->flags & TCP_FLAG_FIN && ses0->state == DET44_SESSION_TCP_ESTABLISHED) ses0->state = DET44_SESSION_TCP_FIN_WAIT; else if (tcp0->flags & TCP_FLAG_ACK && ses0->state == DET44_SESSION_TCP_FIN_WAIT) snat_det_ses_close (mp0, ses0); else if (tcp0->flags & TCP_FLAG_FIN && ses0->state == DET44_SESSION_TCP_CLOSE_WAIT) ses0->state = DET44_SESSION_TCP_LAST_ACK; else if (tcp0->flags == 0 && ses0->state == DET44_SESSION_UNKNOWN) ses0->state = DET44_SESSION_TCP_ESTABLISHED; sum0 = tcp0->checksum; sum0 = ip_csum_update (sum0, old_addr0.as_u32, new_addr0.as_u32, ip4_header_t, dst_address /* changed member */ ); sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t /* cheat */ , length /* changed member */ ); mss_clamping (dm->mss_clamping, tcp0, &sum0); tcp0->checksum = ip_csum_fold (sum0); } else { ses0->state = DET44_SESSION_UDP_ACTIVE; if (PREDICT_FALSE (udp0->checksum)) { sum0 = udp0->checksum; sum0 = ip_csum_update (sum0, old_addr0.as_u32, new_addr0.as_u32, ip4_header_t, dst_address /* changed member */ ); sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t /* cheat */ , length /* changed member */ ); udp0->checksum = ip_csum_fold (sum0); } } switch (ses0->state) { case DET44_SESSION_UDP_ACTIVE: ses0->expire = now + dm->timeouts.udp; break; case DET44_SESSION_TCP_SYN_SENT: case DET44_SESSION_TCP_FIN_WAIT: case DET44_SESSION_TCP_CLOSE_WAIT: case DET44_SESSION_TCP_LAST_ACK: ses0->expire = now + dm->timeouts.tcp.transitory; break; case DET44_SESSION_TCP_ESTABLISHED: ses0->expire = now + dm->timeouts.tcp.established; break; } trace00: if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { det44_in2out_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 (ses0) t->session_index = ses0 - mp0->sessions; } pkts_processed += next0 != DET44_IN2OUT_NEXT_DROP; n_left_from--; next[0] = next0; next++; } vlib_buffer_enqueue_to_next (vm, node, from, (u16 *) nexts, frame->n_vectors); vlib_node_increment_counter (vm, dm->in2out_node_index, DET44_IN2OUT_ERROR_IN2OUT_PACKETS, pkts_processed); return frame->n_vectors; } VLIB_REGISTER_NODE (det44_in2out_node) = { .name = "det44-in2out", .vector_size = sizeof (u32), .format_trace = format_det44_in2out_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN(det44_in2out_error_strings), .error_strings = det44_in2out_error_strings, .runtime_data_bytes = sizeof (det44_runtime_t), .n_next_nodes = DET44_IN2OUT_N_NEXT, /* edit / add dispositions here */ .next_nodes = { [DET44_IN2OUT_NEXT_DROP] = "error-drop", [DET44_IN2OUT_NEXT_LOOKUP] = "ip4-lookup", [DET44_IN2OUT_NEXT_ICMP_ERROR] = "ip4-icmp-error", }, }; /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */