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_translation.h>
19 #include <cnat/cnat_inline.h>
20 #include <cnat/cnat_src_policy.h>
22 #include <vnet/dpo/load_balance.h>
23 #include <vnet/dpo/load_balance_map.h>
25 #include <vnet/ip/ip4_inlines.h>
26 #include <vnet/ip/ip6_inlines.h>
28 typedef struct cnat_translation_trace_t_
30 cnat_session_t session;
31 cnat_translation_t tr;
35 } cnat_translation_trace_t;
37 typedef enum cnat_translation_next_t_
39 CNAT_TRANSLATION_NEXT_DROP,
40 CNAT_TRANSLATION_NEXT_LOOKUP,
41 CNAT_TRANSLATION_N_NEXT,
42 } cnat_translation_next_t;
44 vlib_node_registration_t cnat_vip_ip4_node;
45 vlib_node_registration_t cnat_vip_ip6_node;
48 format_cnat_translation_trace (u8 * s, va_list * args)
50 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
51 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
52 cnat_translation_trace_t *t = va_arg (*args, cnat_translation_trace_t *);
55 s = format (s, "found: %U", format_cnat_session, &t->session, 1);
56 else if (t->created_session)
57 s = format (s, "created: %U\n tr: %U",
58 format_cnat_session, &t->session, 1,
59 format_cnat_translation, &t->tr, 0);
61 s = format (s, "tr pass: %U", format_cnat_translation, &t->tr, 0);
63 s = format (s, "not found");
67 /* CNat sub for NAT behind a fib entry (VIP or interposed real IP) */
69 cnat_vip_node_fn (vlib_main_t * vm,
70 vlib_node_runtime_t * node,
72 cnat_node_ctx_t * ctx, int rv, cnat_session_t * session)
74 vlib_combined_counter_main_t *cntm = &cnat_translation_counters;
75 const cnat_translation_t *ct = NULL;
76 ip4_header_t *ip4 = NULL;
78 ip6_header_t *ip6 = NULL;
83 int created_session = 0;
84 cnat_src_policy_main_t *cspm = &cnat_src_policy_main;
85 if (AF_IP4 == ctx->af)
87 ip4 = vlib_buffer_get_current (b);
88 iproto = ip4->protocol;
89 udp0 = (udp_header_t *) (ip4 + 1);
93 ip6 = vlib_buffer_get_current (b);
94 iproto = ip6->protocol;
95 udp0 = (udp_header_t *) (ip6 + 1);
98 cc = cnat_client_get (vnet_buffer (b)->ip.adj_index[VLIB_TX]);
100 if (iproto != IP_PROTOCOL_UDP && iproto != IP_PROTOCOL_TCP
101 && iproto != IP_PROTOCOL_ICMP && iproto != IP_PROTOCOL_ICMP6)
103 /* Dont translate & follow the fib programming */
104 next0 = cc->cc_parent.dpoi_next_node;
105 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
111 /* session table hit */
112 cnat_timestamp_update (session->value.cs_ts_index, ctx->now);
114 if (INDEX_INVALID != session->value.cs_lbi)
116 /* Translate & follow the translation given LB */
117 ct = cnat_translation_get (session->value.ct_index);
118 next0 = ct->ct_lb.dpoi_next_node;
119 vnet_buffer (b)->ip.adj_index[VLIB_TX] = session->value.cs_lbi;
121 else if (session->value.flags & CNAT_SESSION_FLAG_HAS_SNAT)
123 /* The return needs DNAT, so we need an additionnal
124 * lookup after translation */
125 next0 = CNAT_TRANSLATION_NEXT_LOOKUP;
129 /* Translate & follow the fib programming */
130 next0 = cc->cc_parent.dpoi_next_node;
131 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
137 cnat_find_translation (cc->parent_cci,
138 clib_host_to_net_u16 (udp0->dst_port), iproto);
141 /* Dont translate & Follow the fib programming */
142 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
143 next0 = cc->cc_parent.dpoi_next_node;
147 /* New flow, create the sessions */
148 const load_balance_t *lb0;
150 u32 hash_c0, bucket0;
151 u32 rsession_flags = 0;
152 const dpo_id_t *dpo0;
154 lb0 = load_balance_get (ct->ct_lb.dpoi_index);
155 if (!lb0->lb_n_buckets)
157 /* Dont translate & Follow the fib programming */
158 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
159 next0 = cc->cc_parent.dpoi_next_node;
163 /* session table miss */
164 hash_c0 = (AF_IP4 == ctx->af ?
165 ip4_compute_flow_hash (ip4, lb0->lb_hash_config) :
166 ip6_compute_flow_hash (ip6, lb0->lb_hash_config));
167 bucket0 = hash_c0 % lb0->lb_n_buckets;
168 dpo0 = load_balance_get_fwd_bucket (lb0, bucket0);
170 /* add the session */
171 trk0 = &ct->ct_paths[bucket0];
173 ip46_address_copy (&session->value.cs_ip[VLIB_TX],
174 &trk0->ct_ep[VLIB_TX].ce_ip.ip);
175 if (ip_address_is_zero (&trk0->ct_ep[VLIB_RX].ce_ip))
177 if (AF_IP4 == ctx->af)
178 ip46_address_set_ip4 (&session->value.cs_ip[VLIB_RX],
181 ip46_address_set_ip6 (&session->value.cs_ip[VLIB_RX],
186 /* We source NAT with the translation */
187 rsession_flags |= CNAT_SESSION_FLAG_HAS_SNAT;
188 ip46_address_copy (&session->value.cs_ip[VLIB_RX],
189 &trk0->ct_ep[VLIB_RX].ce_ip.ip);
191 session->value.cs_port[VLIB_TX] =
192 clib_host_to_net_u16 (trk0->ct_ep[VLIB_TX].ce_port);
193 session->value.cs_port[VLIB_RX] =
194 clib_host_to_net_u16 (trk0->ct_ep[VLIB_RX].ce_port);
196 session->value.ct_index = ct - cnat_translation_pool;
197 session->value.cs_lbi = dpo0->dpoi_index;
199 rv = cspm->vip_policy (vm, b, session, &rsession_flags, ct, ctx);
200 if (CNAT_SOURCE_ERROR_USE_DEFAULT == rv)
201 rv = cspm->default_policy (vm, b, session, &rsession_flags, ct, ctx);
204 if (CNAT_SOURCE_ERROR_EXHAUSTED_PORTS == rv)
205 vlib_node_increment_counter (vm, cnat_vip_ip4_node.index,
206 CNAT_ERROR_EXHAUSTED_PORTS, 1);
207 next0 = CNAT_TRANSLATION_NEXT_DROP;
211 /* refcnt session in current client */
212 cnat_client_cnt_session (cc);
213 cnat_session_create (session, ctx, rsession_flags);
216 next0 = ct->ct_lb.dpoi_next_node;
217 vnet_buffer (b)->ip.adj_index[VLIB_TX] = session->value.cs_lbi;
220 if (AF_IP4 == ctx->af)
221 cnat_translation_ip4 (session, ip4, udp0);
223 cnat_translation_ip6 (session, ip6, udp0);
227 cti = ct - cnat_translation_pool;
228 vlib_increment_combined_counter (cntm, ctx->thread_index, cti, 1,
229 vlib_buffer_length_in_chain (vm, b));
233 if (PREDICT_FALSE (ctx->do_trace))
235 cnat_translation_trace_t *t;
237 t = vlib_add_trace (vm, node, b, sizeof (*t));
239 t->found_session = !rv;
240 t->created_session = created_session;
241 if (t->found_session || t->created_session)
242 clib_memcpy (&t->session, session, sizeof (t->session));
243 t->has_tr = (NULL != ct);
245 clib_memcpy (&t->tr, ct, sizeof (cnat_translation_t));
250 VLIB_NODE_FN (cnat_vip_ip4_node) (vlib_main_t * vm,
251 vlib_node_runtime_t * node,
252 vlib_frame_t * frame)
254 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
255 return cnat_node_inline (vm, node, frame, cnat_vip_node_fn, AF_IP4,
257 return cnat_node_inline (vm, node, frame, cnat_vip_node_fn, AF_IP4,
261 VLIB_NODE_FN (cnat_vip_ip6_node) (vlib_main_t * vm,
262 vlib_node_runtime_t * node,
263 vlib_frame_t * frame)
265 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
266 return cnat_node_inline (vm, node, frame, cnat_vip_node_fn, AF_IP6,
268 return cnat_node_inline (vm, node, frame, cnat_vip_node_fn, AF_IP6,
273 VLIB_REGISTER_NODE (cnat_vip_ip4_node) =
275 .name = "ip4-cnat-tx",
276 .vector_size = sizeof (u32),
277 .format_trace = format_cnat_translation_trace,
278 .type = VLIB_NODE_TYPE_INTERNAL,
280 .n_next_nodes = CNAT_TRANSLATION_N_NEXT,
283 [CNAT_TRANSLATION_NEXT_DROP] = "ip4-drop",
284 [CNAT_TRANSLATION_NEXT_LOOKUP] = "ip4-lookup",
287 VLIB_REGISTER_NODE (cnat_vip_ip6_node) =
289 .name = "ip6-cnat-tx",
290 .vector_size = sizeof (u32),
291 .format_trace = format_cnat_translation_trace,
292 .type = VLIB_NODE_TYPE_INTERNAL,
294 .n_next_nodes = CNAT_TRANSLATION_N_NEXT,
297 [CNAT_TRANSLATION_NEXT_DROP] = "ip6-drop",
298 [CNAT_TRANSLATION_NEXT_LOOKUP] = "ip6-lookup",
304 * fd.io coding-style-patch-verification: ON
307 * eval: (c-set-style "gnu")