2 * ipsec_tun.h : IPSEC tunnel protection
4 * Copyright (c) 2015 Cisco and/or its affiliates.
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
18 #include <vnet/ipsec/ipsec_tun.h>
19 #include <vnet/ipsec/esp.h>
20 #include <vnet/udp/udp.h>
23 * Pool of tunnel protection objects
25 ipsec_tun_protect_t *ipsec_protect_pool;
28 * DB of protected tunnels
30 typedef struct ipsec_protect_db_t_
36 static ipsec_protect_db_t ipsec_protect_db;
39 ipsec_tun_protect_feature_set (ipsec_tun_protect_t * itp, u8 enable)
41 u32 sai = itp->itp_out_sa;
44 const char *enc_node = (ip46_address_is_ip4 (&itp->itp_tun.src) ?
45 "esp4-encrypt-tun" : "esp6-encrypt-tun");
47 if (itp->itp_flags & IPSEC_PROTECT_L2)
49 rv = vnet_feature_enable_disable ("ethernet-output",
51 itp->itp_sw_if_index, enable,
56 rv = vnet_feature_enable_disable ("ip4-output",
58 itp->itp_sw_if_index, enable,
60 rv = vnet_feature_enable_disable ("ip6-output",
62 itp->itp_sw_if_index, enable,
70 ipsec_tun_protect_db_add (ipsec_main_t * im, const ipsec_tun_protect_t * itp)
76 FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
78 sa = ipsec_sa_get (sai);
80 ipsec_tun_lkup_result_t res = {
81 .tun_index = itp - ipsec_protect_pool,
86 * The key is formed from the tunnel's destination
87 * as the packet lookup is done from the packet's source
89 if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
91 ipsec4_tunnel_key_t key = {
92 .remote_ip = itp->itp_crypto.dst.ip4,
93 .spi = clib_host_to_net_u32 (sa->spi),
95 hash_set (im->tun4_protect_by_key, key.as_u64, res.as_u64);
96 if (1 == hash_elts(im->tun4_protect_by_key))
97 udp_register_dst_port (vlib_get_main(),
99 ipsec4_tun_input_node.index, 1);
103 ipsec6_tunnel_key_t key = {
104 .remote_ip = itp->itp_crypto.dst.ip6,
105 .spi = clib_host_to_net_u32 (sa->spi),
107 hash_set_mem_alloc (&im->tun6_protect_by_key, &key, res.as_u64);
114 ipsec_tun_protect_db_remove (ipsec_main_t * im,
115 const ipsec_tun_protect_t * itp)
117 const ipsec_sa_t *sa;
120 FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
122 if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
124 ipsec4_tunnel_key_t key = {
125 .remote_ip = itp->itp_crypto.dst.ip4,
126 .spi = clib_host_to_net_u32 (sa->spi),
128 hash_unset (im->tun4_protect_by_key, key.as_u64);
129 if (0 == hash_elts(im->tun4_protect_by_key))
130 udp_unregister_dst_port (vlib_get_main(),
136 ipsec6_tunnel_key_t key = {
137 .remote_ip = itp->itp_crypto.dst.ip6,
138 .spi = clib_host_to_net_u32 (sa->spi),
140 hash_unset_mem_free (&im->tun6_protect_by_key, &key);
147 ipsec_tun_protect_config (ipsec_main_t * im,
148 ipsec_tun_protect_t * itp, u32 sa_out, u32 * sas_in)
153 itp->itp_n_sa_in = vec_len (sas_in);
154 for (ii = 0; ii < itp->itp_n_sa_in; ii++)
155 itp->itp_in_sas[ii] = sas_in[ii];
156 itp->itp_out_sa = sa_out;
159 FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
161 if (ipsec_sa_is_set_IS_TUNNEL (sa))
163 itp->itp_crypto.src = sa->tunnel_dst_addr;
164 itp->itp_crypto.dst = sa->tunnel_src_addr;
165 ipsec_sa_set_IS_PROTECT (sa);
166 itp->itp_flags |= IPSEC_PROTECT_ENCAPED;
170 itp->itp_crypto.src = itp->itp_tun.src;
171 itp->itp_crypto.dst = itp->itp_tun.dst;
172 itp->itp_flags &= ~IPSEC_PROTECT_ENCAPED;
178 * add to the DB against each SA
180 ipsec_tun_protect_db_add (im, itp);
183 * enable the encrypt feature for egress.
185 ipsec_tun_protect_feature_set (itp, 1);
190 ipsec_tun_protect_unconfig (ipsec_main_t * im, ipsec_tun_protect_t * itp)
195 ipsec_tun_protect_feature_set (itp, 0);
198 FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
200 ipsec_sa_unset_IS_PROTECT (sa);
203 ipsec_tun_protect_db_remove (im, itp);
205 ipsec_sa_unlock(itp->itp_out_sa);
207 FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
209 ipsec_sa_unlock(sai);
215 ipsec_tun_protect_find (u32 sw_if_index)
217 if (vec_len (ipsec_protect_db.tunnels) < sw_if_index)
218 return (INDEX_INVALID);
220 return (ipsec_protect_db.tunnels[sw_if_index]);
224 ipsec_tun_protect_update (u32 sw_if_index, u32 sa_out, u32 * sas_in)
227 ipsec_tun_protect_t *itp;
233 vec_validate_init_empty (ipsec_protect_db.tunnels, sw_if_index,
235 itpi = ipsec_protect_db.tunnels[sw_if_index];
237 vec_foreach_index (ii, sas_in)
239 sas_in[ii] = ipsec_sa_find_and_lock (sas_in[ii]);
240 if (~0 == sas_in[ii])
242 rv = VNET_API_ERROR_INVALID_VALUE;
247 sa_out = ipsec_sa_find_and_lock (sa_out);
251 rv = VNET_API_ERROR_INVALID_VALUE;
255 if (INDEX_INVALID == itpi)
257 vnet_device_class_t *dev_class;
258 vnet_hw_interface_t *hi;
262 vnm = vnet_get_main ();
263 hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
264 dev_class = vnet_get_device_class (vnm, hi->dev_class_index);
266 if (NULL == dev_class->ip_tun_desc)
268 rv = VNET_API_ERROR_INVALID_SW_IF_INDEX;
272 pool_get_zero (ipsec_protect_pool, itp);
274 itp->itp_sw_if_index = sw_if_index;
275 ipsec_protect_db.tunnels[sw_if_index] = itp - ipsec_protect_pool;
276 ipsec_protect_db.count++;
278 itp->itp_n_sa_in = vec_len (sas_in);
279 for (ii = 0; ii < itp->itp_n_sa_in; ii++)
280 itp->itp_in_sas[ii] = sas_in[ii];
281 itp->itp_out_sa = sa_out;
283 rv = dev_class->ip_tun_desc (sw_if_index,
285 &itp->itp_tun.dst, &is_l2);
291 itp->itp_flags |= IPSEC_PROTECT_L2;
294 * add to the tunnel DB for ingress
295 * - if the SA is in trasnport mode, then the packates will arrivw
296 * with the IP src,dst of the protected tunnel, in which case we can
297 * simply strip the IP header and hand the payload to the protocol
298 * appropriate input handler
299 * - if the SA is in tunnel mode then there are two IP headers present
300 * one for the crytpo tunnel endpoints (described in the SA) and one
301 * for the tunnel endpoints. The outer IP headers in the srriving
302 * packets will have the crypto endpoints. So the DB needs to contain
303 * the crpto endpoint. Once the crypto header is stripped, revealing,
304 * the tunnel-IP we have 2 choices:
305 * 1) do a tunnel lookup based on the revealed header
306 * 2) skip the tunnel lookup and assume that the packet matches the
307 * one that is protected here.
308 * If we did 1) then we would allow our peer to use the SA for tunnel
309 * X to inject traffic onto tunnel Y, this is not good. If we do 2)
310 * then we don't verify that the peer is indeed using SA for tunnel
311 * X and addressing tunnel X. So we take a compromise, once the SA
312 * matches to tunnel X we veriy that the inner IP matches the value
313 * of the tunnel we are protecting, else it's dropped.
315 ipsec_tun_protect_config (im, itp, sa_out, sas_in);
317 if (1 == hash_elts (im->tun4_protect_by_key))
318 ip4_register_protocol (IP_PROTOCOL_IPSEC_ESP,
319 ipsec4_tun_input_node.index);
320 if (1 == hash_elts (im->tun6_protect_by_key))
321 ip6_register_protocol (IP_PROTOCOL_IPSEC_ESP,
322 ipsec6_tun_input_node.index);
326 /* updating SAs only */
327 itp = pool_elt_at_index (ipsec_protect_pool, itpi);
329 ipsec_tun_protect_unconfig (im, itp);
330 ipsec_tun_protect_config (im, itp, sa_out, sas_in);
339 ipsec_tun_protect_del (u32 sw_if_index)
341 ipsec_tun_protect_t *itp;
347 vec_validate_init_empty (ipsec_protect_db.tunnels, sw_if_index,
349 itpi = ipsec_protect_db.tunnels[sw_if_index];
351 if (INDEX_INVALID == itpi)
352 return (VNET_API_ERROR_NO_SUCH_ENTRY);
354 itp = ipsec_tun_protect_get (itpi);
355 ipsec_tun_protect_unconfig (im, itp);
357 ipsec_protect_db.tunnels[itp->itp_sw_if_index] = INDEX_INVALID;
359 pool_put (ipsec_protect_pool, itp);
361 if (0 == hash_elts (im->tun4_protect_by_key))
362 ip4_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
363 if (0 == hash_elts (im->tun6_protect_by_key))
364 ip6_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
370 ipsec_tun_protect_walk (ipsec_tun_protect_walk_cb_t fn, void *ctx)
375 pool_foreach_index(itpi, ipsec_protect_pool,
383 ipsec_tunnel_protect_init (vlib_main_t * vm)
388 im->tun6_protect_by_key = hash_create_mem (0,
389 sizeof (ipsec6_tunnel_key_t),
391 im->tun4_protect_by_key = hash_create (0, sizeof (u64));
396 VLIB_INIT_FUNCTION (ipsec_tunnel_protect_init);
400 * fd.io coding-style-patch-verification: ON
403 * eval: (c-set-style "gnu")