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>
21 #include <cnat/cnat_snat_policy.h>
23 #include <vnet/dpo/load_balance.h>
24 #include <vnet/dpo/load_balance_map.h>
26 #include <vnet/ip/ip4_inlines.h>
27 #include <vnet/ip/ip6_inlines.h>
29 typedef enum cnat_feature_next_
31 CNAT_FEATURE_NEXT_DROP,
33 } cnat_feature_next_t;
35 vlib_node_registration_t cnat_input_feature_ip4_node;
36 vlib_node_registration_t cnat_input_feature_ip6_node;
37 vlib_node_registration_t cnat_output_feature_ip4_node;
38 vlib_node_registration_t cnat_output_feature_ip6_node;
41 cnat_input_feature_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
42 vlib_buffer_t *b, cnat_node_ctx_t *ctx,
43 int session_not_found, cnat_session_t *session)
45 vlib_combined_counter_main_t *cntm = &cnat_translation_counters;
46 const cnat_translation_t *ct = NULL;
47 ip4_header_t *ip4 = NULL;
49 ip6_header_t *ip6 = NULL;
56 /* By default follow arc default next */
57 vnet_feature_next (&next0, b);
59 if (AF_IP4 == ctx->af)
61 ip4 = vlib_buffer_get_current (b);
62 iproto = ip4->protocol;
63 udp0 = (udp_header_t *) (ip4 + 1);
64 cc = cnat_client_ip4_find (
65 &ip4->dst_address); /* TODO do this only if no session? */
69 ip6 = vlib_buffer_get_current (b);
70 iproto = ip6->protocol;
71 udp0 = (udp_header_t *) (ip6 + 1);
72 cc = cnat_client_ip6_find (&ip6->dst_address); /* TODO: same as above */
75 /* Wrong session key */
76 if (session->key.cs_proto == 0)
79 if (!session_not_found)
80 /* session table hit */
81 cnat_timestamp_update (session->value.cs_ts_index, ctx->now);
83 goto trace; /* dst address is not a vip */
86 ct = cnat_find_translation (
87 cc->parent_cci, clib_host_to_net_u16 (udp0->dst_port), iproto);
90 /* TODO: create identity session to avoid slowpath ? */
93 /* New flow, create the sessions */
94 const load_balance_t *lb0;
96 u32 rsession_flags = CNAT_SESSION_FLAG_NO_CLIENT;
99 lb0 = load_balance_get (ct->ct_lb.dpoi_index);
100 if (!lb0->lb_n_buckets)
101 /* Can't translate TODO: should drop / reject? */
104 /* session table miss */
105 trk0 = cnat_load_balance (ct, ctx->af, ip4, ip6, &dpoi_index);
106 if (PREDICT_FALSE (NULL == trk0))
108 /* Dont translate & Follow the fib programming */
109 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
110 next0 = cc->cc_parent.dpoi_next_node;
114 ip46_address_copy (&session->value.cs_ip[VLIB_TX],
115 &trk0->ct_ep[VLIB_TX].ce_ip.ip);
117 /* never source nat in this node */
118 if (AF_IP4 == ctx->af)
119 ip46_address_set_ip4 (&session->value.cs_ip[VLIB_RX],
122 ip46_address_set_ip6 (&session->value.cs_ip[VLIB_RX],
125 session->value.cs_port[VLIB_TX] =
126 clib_host_to_net_u16 (trk0->ct_ep[VLIB_TX].ce_port);
127 session->value.cs_port[VLIB_RX] = udp0->src_port;
128 session->value.flags = 0;
130 if (trk0->ct_flags & CNAT_TRK_FLAG_NO_NAT)
132 const dpo_id_t *dpo0;
133 const load_balance_t *lb1;
135 lb1 = load_balance_get (trk0->ct_dpo.dpoi_index);
136 /* Assume backend has exactly one item in LB */
137 dpo0 = load_balance_get_bucket_i (lb1, 0);
139 session->value.dpoi_next_node = dpo0->dpoi_next_node;
140 session->value.cs_lbi = dpo0->dpoi_index;
141 session->value.flags = CNAT_SESSION_FLAG_NO_NAT;
144 /* refcnt session in current client */
145 cnat_client_cnt_session (cc);
146 cnat_session_create (session, ctx);
147 if (!(ct->flags & CNAT_TR_FLAG_NO_RETURN_SESSION))
148 cnat_rsession_create (session, ctx, CNAT_LOCATION_OUTPUT,
150 trace_flags |= CNAT_TRACE_SESSION_CREATED;
153 if (session->value.flags & CNAT_SESSION_FLAG_NO_NAT)
155 /* If we don't translate, directly do the lookup & bypass arc */
156 next0 = session->value.dpoi_next_node;
157 vnet_buffer (b)->ip.adj_index[VLIB_TX] = session->value.cs_lbi;
161 if (AF_IP4 == ctx->af)
162 cnat_translation_ip4 (session, ip4, udp0, vnet_buffer (b)->oflags);
164 cnat_translation_ip6 (session, ip6, udp0, vnet_buffer (b)->oflags);
168 cti = ct - cnat_translation_pool;
169 vlib_increment_combined_counter (cntm, ctx->thread_index, cti, 1,
170 vlib_buffer_length_in_chain (vm, b));
174 if (PREDICT_FALSE (ctx->do_trace))
176 trace_flags |= session_not_found ? 0 : CNAT_TRACE_SESSION_FOUND;
177 cnat_add_trace (vm, node, b, session, ct, trace_flags);
182 VLIB_NODE_FN (cnat_input_feature_ip4_node)
183 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
185 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
186 return cnat_node_inline (vm, node, frame, cnat_input_feature_fn, AF_IP4,
187 CNAT_LOCATION_INPUT, 1 /* do_trace */);
188 return cnat_node_inline (vm, node, frame, cnat_input_feature_fn, AF_IP4,
189 CNAT_LOCATION_INPUT, 0 /* do_trace */);
192 VLIB_REGISTER_NODE (cnat_input_feature_ip4_node) = {
193 .name = "cnat-input-ip4",
194 .vector_size = sizeof (u32),
195 .format_trace = format_cnat_trace,
196 .type = VLIB_NODE_TYPE_INTERNAL,
197 .n_errors = CNAT_N_ERROR,
198 .error_strings = cnat_error_strings,
199 .sibling_of = "ip4-lookup",
202 VNET_FEATURE_INIT (cnat_in_ip4_feature, static) = {
203 .arc_name = "ip4-unicast",
204 .node_name = "cnat-input-ip4",
205 .runs_before = VNET_FEATURES ("acl-plugin-in-ip4-fa"),
208 VLIB_NODE_FN (cnat_input_feature_ip6_node)
209 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
211 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
212 return cnat_node_inline (vm, node, frame, cnat_input_feature_fn, AF_IP6,
213 CNAT_LOCATION_INPUT, 1 /* do_trace */);
214 return cnat_node_inline (vm, node, frame, cnat_input_feature_fn, AF_IP6,
215 CNAT_LOCATION_INPUT, 0 /* do_trace */);
218 VLIB_REGISTER_NODE (cnat_input_feature_ip6_node) = {
219 .name = "cnat-input-ip6",
220 .vector_size = sizeof (u32),
221 .format_trace = format_cnat_trace,
222 .type = VLIB_NODE_TYPE_INTERNAL,
223 .n_errors = CNAT_N_ERROR,
224 .error_strings = cnat_error_strings,
225 .sibling_of = "ip6-lookup",
228 VNET_FEATURE_INIT (cnat_in_ip6_feature, static) = {
229 .arc_name = "ip6-unicast",
230 .node_name = "cnat-input-ip6",
231 .runs_before = VNET_FEATURES ("acl-plugin-in-ip6-fa"),
234 /* output feature node, creates snat sessions when required and
235 * translates back for existing sessions */
237 cnat_output_feature_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
238 vlib_buffer_t *b, cnat_node_ctx_t *ctx,
239 int session_not_found, cnat_session_t *session)
241 cnat_snat_policy_main_t *cpm = &cnat_snat_policy_main;
242 ip4_header_t *ip4 = NULL;
243 ip_protocol_t iproto;
244 ip6_header_t *ip6 = NULL;
253 /* By default follow arc default next */
254 vnet_feature_next (&next0, b);
255 iph_offset = vnet_buffer (b)->ip.save_rewrite_length;
257 if (AF_IP4 == ctx->af)
259 ip4 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b) + iph_offset);
260 iproto = ip4->protocol;
261 udp0 = (udp_header_t *) (ip4 + 1);
265 ip6 = (ip6_header_t *) ((u8 *) vlib_buffer_get_current (b) + iph_offset);
266 iproto = ip6->protocol;
267 udp0 = (udp_header_t *) (ip6 + 1);
270 /* Wrong session key */
271 if (session->key.cs_proto == 0)
274 if (!session_not_found)
276 /* session table hit */
277 cnat_timestamp_update (session->value.cs_ts_index, ctx->now);
279 else if (!cpm->snat_policy)
283 do_snat = cpm->snat_policy (b, session);
287 if (AF_IP4 == ctx->af)
289 if (ip_address_is_zero (&cpm->snat_ip4.ce_ip))
292 ip46_address_set_ip4 (&session->value.cs_ip[VLIB_RX],
293 &ip_addr_v4 (&cpm->snat_ip4.ce_ip));
294 ip46_address_set_ip4 (&session->value.cs_ip[VLIB_TX],
299 if (ip_address_is_zero (&cpm->snat_ip6.ce_ip))
302 ip46_address_set_ip6 (&session->value.cs_ip[VLIB_RX],
303 &ip_addr_v6 (&cpm->snat_ip6.ce_ip));
304 ip46_address_set_ip6 (&session->value.cs_ip[VLIB_TX],
308 rv = cnat_allocate_port (&sport, iproto);
311 vlib_node_increment_counter (vm, cnat_output_feature_ip6_node.index,
312 CNAT_ERROR_EXHAUSTED_PORTS, 1);
313 next0 = CNAT_FEATURE_NEXT_DROP;
316 session->value.cs_port[VLIB_RX] = sport;
317 session->value.cs_port[VLIB_TX] = sport;
318 if (iproto == IP_PROTOCOL_TCP || iproto == IP_PROTOCOL_UDP)
319 session->value.cs_port[VLIB_TX] = udp0->dst_port;
321 session->value.cs_lbi = INDEX_INVALID;
322 session->value.flags =
323 CNAT_SESSION_FLAG_NO_CLIENT | CNAT_SESSION_FLAG_ALLOC_PORT;
325 trace_flags |= CNAT_TRACE_SESSION_CREATED;
327 cnat_session_create (session, ctx);
328 cnat_rsession_create (session, ctx, CNAT_LOCATION_INPUT,
329 CNAT_SESSION_FLAG_NO_CLIENT |
330 CNAT_SESSION_RETRY_SNAT);
333 if (AF_IP4 == ctx->af)
334 cnat_translation_ip4 (session, ip4, udp0, vnet_buffer (b)->oflags);
336 cnat_translation_ip6 (session, ip6, udp0, vnet_buffer (b)->oflags);
339 if (PREDICT_FALSE (ctx->do_trace))
341 trace_flags |= do_snat ? 0 : CNAT_TRACE_NO_NAT;
342 trace_flags |= session_not_found ? 0 : CNAT_TRACE_SESSION_FOUND;
343 cnat_add_trace (vm, node, b, session, NULL, trace_flags);
348 VLIB_NODE_FN (cnat_output_feature_ip4_node)
349 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
351 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
352 return cnat_node_inline (vm, node, frame, cnat_output_feature_fn, AF_IP4,
353 CNAT_LOCATION_OUTPUT, 1 /* do_trace */);
354 return cnat_node_inline (vm, node, frame, cnat_output_feature_fn, AF_IP4,
355 CNAT_LOCATION_OUTPUT, 0 /* do_trace */);
358 VLIB_REGISTER_NODE (cnat_output_feature_ip4_node) = {
359 .name = "cnat-output-ip4",
360 .vector_size = sizeof (u32),
361 .format_trace = format_cnat_trace,
362 .type = VLIB_NODE_TYPE_INTERNAL,
363 .n_errors = CNAT_N_ERROR,
364 .error_strings = cnat_error_strings,
365 .n_next_nodes = CNAT_FEATURE_N_NEXT,
367 [CNAT_FEATURE_NEXT_DROP] = "error-drop",
371 VNET_FEATURE_INIT (cnat_out_ip4_feature, static) = {
372 .arc_name = "ip4-output",
373 .node_name = "cnat-output-ip4",
374 .runs_before = VNET_FEATURES ("gso-ip4"),
375 .runs_after = VNET_FEATURES ("acl-plugin-out-ip4-fa"),
378 VLIB_NODE_FN (cnat_output_feature_ip6_node)
379 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
381 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
382 return cnat_node_inline (vm, node, frame, cnat_output_feature_fn, AF_IP6,
383 CNAT_LOCATION_OUTPUT, 1 /* do_trace */);
384 return cnat_node_inline (vm, node, frame, cnat_output_feature_fn, AF_IP6,
385 CNAT_LOCATION_OUTPUT, 0 /* do_trace */);
388 VLIB_REGISTER_NODE (cnat_output_feature_ip6_node) = {
389 .name = "cnat-output-ip6",
390 .vector_size = sizeof (u32),
391 .format_trace = format_cnat_trace,
392 .type = VLIB_NODE_TYPE_INTERNAL,
393 .n_errors = CNAT_N_ERROR,
394 .error_strings = cnat_error_strings,
395 .n_next_nodes = CNAT_FEATURE_N_NEXT,
397 [CNAT_FEATURE_NEXT_DROP] = "error-drop",
401 VNET_FEATURE_INIT (cnat_out_ip6_feature, static) = {
402 .arc_name = "ip6-output",
403 .node_name = "cnat-output-ip6",
404 .runs_before = VNET_FEATURES ("gso-ip6"),
405 .runs_after = VNET_FEATURES ("acl-plugin-out-ip6-fa"),
409 * fd.io coding-style-patch-verification: ON
412 * eval: (c-set-style "gnu")