2 * Copyright (c) 2020 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 #include <vlibmemory/api.h>
17 #include <cnat/cnat_node.h>
18 #include <cnat/cnat_inline.h>
19 #include <cnat/cnat_src_policy.h>
21 typedef enum cnat_translation_next_t_
23 CNAT_TRANSLATION_NEXT_DROP,
24 CNAT_TRANSLATION_NEXT_LOOKUP,
25 CNAT_TRANSLATION_N_NEXT,
26 } cnat_translation_next_t;
28 vlib_node_registration_t cnat_vip_ip4_node;
29 vlib_node_registration_t cnat_vip_ip6_node;
31 /* CNat sub for NAT behind a fib entry (VIP or interposed real IP) */
33 cnat_vip_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_buffer_t *b,
34 cnat_node_ctx_t *ctx, int session_not_found,
35 cnat_session_t *session)
37 vlib_combined_counter_main_t *cntm = &cnat_translation_counters;
38 cnat_src_policy_main_t *cspm = &cnat_src_policy_main;
39 const cnat_translation_t *ct = NULL;
40 ip4_header_t *ip4 = NULL;
42 ip6_header_t *ip6 = NULL;
50 if (AF_IP4 == ctx->af)
52 ip4 = vlib_buffer_get_current (b);
53 iproto = ip4->protocol;
54 udp0 = (udp_header_t *) (ip4 + 1);
58 ip6 = vlib_buffer_get_current (b);
59 iproto = ip6->protocol;
60 udp0 = (udp_header_t *) (ip6 + 1);
63 cc = cnat_client_get (vnet_buffer (b)->ip.adj_index[VLIB_TX]);
65 if (iproto != IP_PROTOCOL_UDP && iproto != IP_PROTOCOL_TCP
66 && iproto != IP_PROTOCOL_ICMP && iproto != IP_PROTOCOL_ICMP6)
68 /* Dont translate & follow the fib programming */
69 next0 = cc->cc_parent.dpoi_next_node;
70 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
74 if (!session_not_found)
76 /* session table hit */
77 cnat_timestamp_update (session->value.cs_ts_index, ctx->now);
79 if (INDEX_INVALID != session->value.cs_lbi)
81 /* Translate & follow the translation given LB */
82 next0 = session->value.dpoi_next_node;
83 vnet_buffer (b)->ip.adj_index[VLIB_TX] = session->value.cs_lbi;
85 else if (session->value.flags & CNAT_SESSION_FLAG_HAS_SNAT)
87 /* The return needs DNAT, so we need an additionnal
88 * lookup after translation */
89 next0 = CNAT_TRANSLATION_NEXT_LOOKUP;
93 /* Translate & follow the fib programming */
94 next0 = cc->cc_parent.dpoi_next_node;
95 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
101 cnat_find_translation (cc->parent_cci,
102 clib_host_to_net_u16 (udp0->dst_port), iproto);
105 /* Dont translate & Follow the fib programming */
106 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
107 next0 = cc->cc_parent.dpoi_next_node;
111 /* New flow, create the sessions */
113 u32 rsession_flags = 0;
116 trk0 = cnat_load_balance (ct, ctx->af, ip4, ip6, &dpoi_index);
117 if (PREDICT_FALSE (NULL == trk0))
119 /* Dont translate & Follow the fib programming */
120 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
121 next0 = cc->cc_parent.dpoi_next_node;
125 /* add the session */
126 ip46_address_copy (&session->value.cs_ip[VLIB_TX],
127 &trk0->ct_ep[VLIB_TX].ce_ip.ip);
128 if (ip_address_is_zero (&trk0->ct_ep[VLIB_RX].ce_ip))
130 if (AF_IP4 == ctx->af)
131 ip46_address_set_ip4 (&session->value.cs_ip[VLIB_RX],
134 ip46_address_set_ip6 (&session->value.cs_ip[VLIB_RX],
139 /* We source NAT with the translation */
140 rsession_flags |= CNAT_SESSION_FLAG_HAS_SNAT;
141 ip46_address_copy (&session->value.cs_ip[VLIB_RX],
142 &trk0->ct_ep[VLIB_RX].ce_ip.ip);
144 session->value.cs_port[VLIB_TX] =
145 clib_host_to_net_u16 (trk0->ct_ep[VLIB_TX].ce_port);
146 session->value.cs_port[VLIB_RX] =
147 clib_host_to_net_u16 (trk0->ct_ep[VLIB_RX].ce_port);
149 session->value.dpoi_next_node = ct->ct_lb.dpoi_next_node;
150 session->value.cs_lbi = dpoi_index;
152 rv = cspm->vip_policy (vm, b, session, &rsession_flags, ct, ctx);
153 if (CNAT_SOURCE_ERROR_USE_DEFAULT == rv)
154 rv = cspm->default_policy (vm, b, session, &rsession_flags, ct, ctx);
157 if (CNAT_SOURCE_ERROR_EXHAUSTED_PORTS == rv)
159 vlib_node_registration_t *node =
160 (AF_IP4 == ctx->af) ? &cnat_vip_ip4_node : &cnat_vip_ip6_node;
161 vlib_node_increment_counter (vm, node->index,
162 CNAT_ERROR_EXHAUSTED_PORTS, 1);
164 next0 = CNAT_TRANSLATION_NEXT_DROP;
168 /* refcnt session in current client */
169 cnat_client_cnt_session (cc);
170 cnat_session_create (session, ctx, CNAT_LOCATION_FIB, rsession_flags);
171 trace_flags |= CNAT_TRACE_SESSION_CREATED;
173 next0 = ct->ct_lb.dpoi_next_node;
174 vnet_buffer (b)->ip.adj_index[VLIB_TX] = session->value.cs_lbi;
177 if (AF_IP4 == ctx->af)
178 cnat_translation_ip4 (session, ip4, udp0);
180 cnat_translation_ip6 (session, ip6, udp0);
184 cti = ct - cnat_translation_pool;
185 vlib_increment_combined_counter (cntm, ctx->thread_index, cti, 1,
186 vlib_buffer_length_in_chain (vm, b));
190 if (PREDICT_FALSE (ctx->do_trace))
192 trace_flags |= session_not_found ? 0 : CNAT_TRACE_SESSION_FOUND;
193 cnat_add_trace (vm, node, b, session, ct, trace_flags);
198 VLIB_NODE_FN (cnat_vip_ip4_node) (vlib_main_t * vm,
199 vlib_node_runtime_t * node,
200 vlib_frame_t * frame)
202 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
203 return cnat_node_inline (vm, node, frame, cnat_vip_node_fn, AF_IP4,
204 CNAT_LOCATION_FIB, 1 /* do_trace */);
205 return cnat_node_inline (vm, node, frame, cnat_vip_node_fn, AF_IP4,
206 CNAT_LOCATION_FIB, 0 /* do_trace */);
209 VLIB_NODE_FN (cnat_vip_ip6_node) (vlib_main_t * vm,
210 vlib_node_runtime_t * node,
211 vlib_frame_t * frame)
213 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
214 return cnat_node_inline (vm, node, frame, cnat_vip_node_fn, AF_IP6,
215 CNAT_LOCATION_FIB, 1 /* do_trace */);
216 return cnat_node_inline (vm, node, frame, cnat_vip_node_fn, AF_IP6,
217 CNAT_LOCATION_FIB, 0 /* do_trace */);
220 VLIB_REGISTER_NODE (cnat_vip_ip4_node) =
222 .name = "ip4-cnat-tx",
223 .vector_size = sizeof (u32),
224 .format_trace = format_cnat_trace,
225 .type = VLIB_NODE_TYPE_INTERNAL,
227 .n_next_nodes = CNAT_TRANSLATION_N_NEXT,
230 [CNAT_TRANSLATION_NEXT_DROP] = "ip4-drop",
231 [CNAT_TRANSLATION_NEXT_LOOKUP] = "ip4-lookup",
234 VLIB_REGISTER_NODE (cnat_vip_ip6_node) =
236 .name = "ip6-cnat-tx",
237 .vector_size = sizeof (u32),
238 .format_trace = format_cnat_trace,
239 .type = VLIB_NODE_TYPE_INTERNAL,
241 .n_next_nodes = CNAT_TRANSLATION_N_NEXT,
244 [CNAT_TRANSLATION_NEXT_DROP] = "ip6-drop",
245 [CNAT_TRANSLATION_NEXT_LOOKUP] = "ip6-lookup",
250 * fd.io coding-style-patch-verification: ON
253 * eval: (c-set-style "gnu")