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.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 if (session->key.cs_proto == 0)
78 if (!session_not_found)
79 /* session table hit */
80 cnat_timestamp_update (session->value.cs_ts_index, ctx->now);
82 goto trace; /* dst address is not a vip */
85 ct = cnat_find_translation (
86 cc->parent_cci, clib_host_to_net_u16 (udp0->dst_port), iproto);
89 /* TODO: create identity session to avoid slowpath ? */
92 /* New flow, create the sessions */
93 const load_balance_t *lb0;
95 u32 rsession_flags = CNAT_SESSION_FLAG_NO_CLIENT;
98 lb0 = load_balance_get (ct->ct_lb.dpoi_index);
99 if (!lb0->lb_n_buckets)
100 /* Can't translate TODO: should drop / reject? */
103 /* session table miss */
104 trk0 = cnat_load_balance (ct, ctx->af, ip4, ip6, &dpoi_index);
105 if (PREDICT_FALSE (NULL == trk0))
107 /* Dont translate & Follow the fib programming */
108 vnet_buffer (b)->ip.adj_index[VLIB_TX] = cc->cc_parent.dpoi_index;
109 next0 = cc->cc_parent.dpoi_next_node;
113 ip46_address_copy (&session->value.cs_ip[VLIB_TX],
114 &trk0->ct_ep[VLIB_TX].ce_ip.ip);
116 /* never source nat in this node */
117 if (AF_IP4 == ctx->af)
118 ip46_address_set_ip4 (&session->value.cs_ip[VLIB_RX],
121 ip46_address_set_ip6 (&session->value.cs_ip[VLIB_RX],
124 session->value.cs_port[VLIB_TX] =
125 clib_host_to_net_u16 (trk0->ct_ep[VLIB_TX].ce_port);
126 session->value.cs_port[VLIB_RX] = udp0->src_port;
128 const dpo_id_t *dpo0;
129 const load_balance_t *lb1;
130 fib_entry_t *fib_entry;
131 fib_entry = fib_entry_get (trk0->ct_fei);
133 lb1 = load_balance_get (fib_entry->fe_lb /*[fct] */.dpoi_index);
134 dpo0 = load_balance_get_bucket_i (lb1, 0);
136 session->value.dpoi_next_node = dpo0->dpoi_next_node;
137 session->value.cs_lbi = dpo0->dpoi_index;
139 if (trk0->ct_flags & CNAT_TRK_FLAG_NO_NAT)
140 session->value.flags |= CNAT_SESSION_FLAG_NO_NAT;
142 /* refcnt session in current client */
143 cnat_client_cnt_session (cc);
144 cnat_session_create (session, ctx, CNAT_LOCATION_OUTPUT, rsession_flags);
145 trace_flags |= CNAT_TRACE_SESSION_CREATED;
148 next0 = session->value.dpoi_next_node;
149 vnet_buffer (b)->ip.adj_index[VLIB_TX] = session->value.cs_lbi;
151 if (session->value.flags & CNAT_SESSION_FLAG_NO_NAT)
154 if (AF_IP4 == ctx->af)
155 cnat_translation_ip4 (session, ip4, udp0);
157 cnat_translation_ip6 (session, ip6, udp0);
161 cti = ct - cnat_translation_pool;
162 vlib_increment_combined_counter (cntm, ctx->thread_index, cti, 1,
163 vlib_buffer_length_in_chain (vm, b));
167 if (PREDICT_FALSE (ctx->do_trace))
169 trace_flags |= session_not_found ? 0 : CNAT_TRACE_SESSION_FOUND;
170 cnat_add_trace (vm, node, b, session, ct, trace_flags);
175 VLIB_NODE_FN (cnat_input_feature_ip4_node)
176 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
178 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
179 return cnat_node_inline (vm, node, frame, cnat_input_feature_fn, AF_IP4,
180 CNAT_LOCATION_INPUT, 1 /* do_trace */);
181 return cnat_node_inline (vm, node, frame, cnat_input_feature_fn, AF_IP4,
182 CNAT_LOCATION_INPUT, 0 /* do_trace */);
185 VLIB_REGISTER_NODE (cnat_input_feature_ip4_node) = {
186 .name = "cnat-input-ip4",
187 .vector_size = sizeof (u32),
188 .format_trace = format_cnat_trace,
189 .type = VLIB_NODE_TYPE_INTERNAL,
190 .n_errors = CNAT_N_ERROR,
191 .error_strings = cnat_error_strings,
192 .n_next_nodes = IP_LOOKUP_N_NEXT,
193 .next_nodes = IP4_LOOKUP_NEXT_NODES,
196 VNET_FEATURE_INIT (cnat_in_ip4_feature, static) = {
197 .arc_name = "ip4-unicast",
198 .node_name = "cnat-input-ip4",
199 .runs_before = VNET_FEATURES ("acl-plugin-in-ip4-fa"),
202 VLIB_NODE_FN (cnat_input_feature_ip6_node)
203 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
205 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
206 return cnat_node_inline (vm, node, frame, cnat_input_feature_fn, AF_IP6,
207 CNAT_LOCATION_INPUT, 1 /* do_trace */);
208 return cnat_node_inline (vm, node, frame, cnat_input_feature_fn, AF_IP6,
209 CNAT_LOCATION_INPUT, 0 /* do_trace */);
212 VLIB_REGISTER_NODE (cnat_input_feature_ip6_node) = {
213 .name = "cnat-input-ip6",
214 .vector_size = sizeof (u32),
215 .format_trace = format_cnat_trace,
216 .type = VLIB_NODE_TYPE_INTERNAL,
217 .n_errors = CNAT_N_ERROR,
218 .error_strings = cnat_error_strings,
219 .n_next_nodes = CNAT_FEATURE_N_NEXT,
221 [CNAT_FEATURE_NEXT_DROP] = "error-drop",
225 VNET_FEATURE_INIT (cnat_in_ip6_feature, static) = {
226 .arc_name = "ip6-unicast",
227 .node_name = "cnat-input-ip6",
228 .runs_before = VNET_FEATURES ("acl-plugin-in-ip6-fa"),
231 /* output feature node, creates snat sessions when required and
232 * translates back for existing sessions */
234 cnat_output_feature_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
235 vlib_buffer_t *b, cnat_node_ctx_t *ctx,
236 int session_not_found, cnat_session_t *session)
238 cnat_main_t *cm = &cnat_main;
239 cnat_snat_policy_main_t *cms = &cnat_snat_policy_main;
240 ip4_header_t *ip4 = NULL;
241 ip_protocol_t iproto;
242 ip6_header_t *ip6 = NULL;
251 /* By default follow arc default next */
252 vnet_feature_next (&next0, b);
253 iph_offset = vnet_buffer (b)->ip.save_rewrite_length;
255 if (AF_IP4 == ctx->af)
257 ip4 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b) + iph_offset);
258 iproto = ip4->protocol;
259 udp0 = (udp_header_t *) (ip4 + 1);
263 ip6 = (ip6_header_t *) ((u8 *) vlib_buffer_get_current (b) + iph_offset);
264 iproto = ip6->protocol;
265 udp0 = (udp_header_t *) (ip6 + 1);
268 if (session->key.cs_proto == 0)
271 if (!session_not_found)
273 /* session table hit */
274 cnat_timestamp_update (session->value.cs_ts_index, ctx->now);
276 else if (!cms->snat_policy)
280 /* TODO: handle errors? */
281 cms->snat_policy (vm, b, session, ctx, &do_snat);
285 if (AF_IP4 == ctx->af)
287 if (ip_address_is_zero (&cm->snat_ip4.ce_ip))
290 ip46_address_set_ip4 (&session->value.cs_ip[VLIB_RX],
291 &ip_addr_v4 (&cm->snat_ip4.ce_ip));
292 ip46_address_set_ip4 (&session->value.cs_ip[VLIB_TX],
297 if (ip_address_is_zero (&cm->snat_ip6.ce_ip))
300 ip46_address_set_ip6 (&session->value.cs_ip[VLIB_RX],
301 &ip_addr_v6 (&cm->snat_ip6.ce_ip));
302 ip46_address_set_ip6 (&session->value.cs_ip[VLIB_TX],
306 rv = cnat_allocate_port (&sport, iproto);
309 vlib_node_increment_counter (vm, cnat_output_feature_ip6_node.index,
310 CNAT_ERROR_EXHAUSTED_PORTS, 1);
311 next0 = CNAT_FEATURE_NEXT_DROP;
314 session->value.cs_port[VLIB_RX] = sport;
315 session->value.cs_port[VLIB_TX] = sport;
316 if (iproto == IP_PROTOCOL_TCP || iproto == IP_PROTOCOL_UDP)
317 session->value.cs_port[VLIB_TX] = udp0->dst_port;
319 session->value.cs_lbi = INDEX_INVALID;
320 session->value.flags =
321 CNAT_SESSION_FLAG_NO_CLIENT | CNAT_SESSION_FLAG_ALLOC_PORT;
323 trace_flags |= CNAT_TRACE_SESSION_CREATED;
324 cnat_session_create (session, ctx, CNAT_LOCATION_INPUT,
325 CNAT_SESSION_FLAG_NO_CLIENT);
328 if (AF_IP4 == ctx->af)
329 cnat_translation_ip4 (session, ip4, udp0);
331 cnat_translation_ip6 (session, ip6, udp0);
334 if (PREDICT_FALSE (ctx->do_trace))
336 trace_flags |= do_snat ? 0 : CNAT_TRACE_NO_NAT;
337 trace_flags |= session_not_found ? 0 : CNAT_TRACE_SESSION_FOUND;
338 cnat_add_trace (vm, node, b, session, NULL, trace_flags);
343 VLIB_NODE_FN (cnat_output_feature_ip4_node)
344 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
346 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
347 return cnat_node_inline (vm, node, frame, cnat_output_feature_fn, AF_IP4,
348 CNAT_LOCATION_OUTPUT, 1 /* do_trace */);
349 return cnat_node_inline (vm, node, frame, cnat_output_feature_fn, AF_IP4,
350 CNAT_LOCATION_OUTPUT, 0 /* do_trace */);
353 VLIB_REGISTER_NODE (cnat_output_feature_ip4_node) = {
354 .name = "cnat-output-ip4",
355 .vector_size = sizeof (u32),
356 .format_trace = format_cnat_trace,
357 .type = VLIB_NODE_TYPE_INTERNAL,
358 .n_errors = CNAT_N_ERROR,
359 .error_strings = cnat_error_strings,
360 .n_next_nodes = CNAT_FEATURE_N_NEXT,
362 [CNAT_FEATURE_NEXT_DROP] = "error-drop",
366 VNET_FEATURE_INIT (cnat_out_ip4_feature, static) = {
367 .arc_name = "ip4-output",
368 .node_name = "cnat-output-ip4",
369 .runs_before = VNET_FEATURES ("gso-ip4"),
370 .runs_after = VNET_FEATURES ("acl-plugin-out-ip4-fa"),
373 VLIB_NODE_FN (cnat_output_feature_ip6_node)
374 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
376 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
377 return cnat_node_inline (vm, node, frame, cnat_output_feature_fn, AF_IP6,
378 CNAT_LOCATION_OUTPUT, 1 /* do_trace */);
379 return cnat_node_inline (vm, node, frame, cnat_output_feature_fn, AF_IP6,
380 CNAT_LOCATION_OUTPUT, 0 /* do_trace */);
383 VLIB_REGISTER_NODE (cnat_output_feature_ip6_node) = {
384 .name = "cnat-output-ip6",
385 .vector_size = sizeof (u32),
386 .format_trace = format_cnat_trace,
387 .type = VLIB_NODE_TYPE_INTERNAL,
388 .n_errors = CNAT_N_ERROR,
389 .error_strings = cnat_error_strings,
390 .n_next_nodes = CNAT_FEATURE_N_NEXT,
392 [CNAT_FEATURE_NEXT_DROP] = "error-drop",
396 VNET_FEATURE_INIT (cnat_out_ip6_feature, static) = {
397 .arc_name = "ip6-output",
398 .node_name = "cnat-output-ip6",
399 .runs_before = VNET_FEATURES ("gso-ip6"),
400 .runs_after = VNET_FEATURES ("acl-plugin-out-ip6-fa"),
404 * fd.io coding-style-patch-verification: ON
407 * eval: (c-set-style "gnu")