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-rw-r--r--src/vnet/ipsec/ipsec_tun.c398
1 files changed, 398 insertions, 0 deletions
diff --git a/src/vnet/ipsec/ipsec_tun.c b/src/vnet/ipsec/ipsec_tun.c
new file mode 100644
index 00000000000..a389cefc991
--- /dev/null
+++ b/src/vnet/ipsec/ipsec_tun.c
@@ -0,0 +1,398 @@
+/*
+ * ipsec_tun.h : IPSEC tunnel protection
+ *
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vnet/ipsec/ipsec_tun.h>
+#include <vnet/ipsec/esp.h>
+#include <vnet/udp/udp.h>
+
+/**
+ * Pool of tunnel protection objects
+ */
+ipsec_tun_protect_t *ipsec_protect_pool;
+
+/**
+ * DB of protected tunnels
+ */
+typedef struct ipsec_protect_db_t_
+{
+ u32 *tunnels;
+ u32 count;
+} ipsec_protect_db_t;
+
+static ipsec_protect_db_t ipsec_protect_db;
+
+static int
+ipsec_tun_protect_feature_set (ipsec_tun_protect_t * itp, u8 enable)
+{
+ u32 sai = itp->itp_out_sa;
+ int is_ip4, is_l2, rv;
+
+ is_ip4 = ip46_address_is_ip4 (&itp->itp_tun.src);
+ is_l2 = itp->itp_flags & IPSEC_PROTECT_L2;
+
+ if (is_ip4)
+ {
+ if (is_l2)
+ rv = vnet_feature_enable_disable ("ethernet-output",
+ "esp4-encrypt-tun",
+ itp->itp_sw_if_index, enable,
+ &sai, sizeof (sai));
+ else
+ rv = vnet_feature_enable_disable ("ip4-output",
+ "esp4-encrypt-tun",
+ itp->itp_sw_if_index, enable,
+ &sai, sizeof (sai));
+ }
+ else
+ {
+ if (is_l2)
+ rv = vnet_feature_enable_disable ("ethernet-output",
+ "esp6-encrypt-tun",
+ itp->itp_sw_if_index, enable,
+ &sai, sizeof (sai));
+ else
+ rv = vnet_feature_enable_disable ("ip6-output",
+ "esp6-encrypt-tun",
+ itp->itp_sw_if_index, enable,
+ &sai, sizeof (sai));
+ }
+
+ ASSERT (!rv);
+ return (rv);
+}
+
+static void
+ipsec_tun_protect_db_add (ipsec_main_t * im, const ipsec_tun_protect_t * itp)
+{
+ const ipsec_sa_t *sa;
+ u32 sai;
+
+ /* *INDENT-OFF* */
+ FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
+ ({
+ sa = ipsec_sa_get (sai);
+
+ ipsec_tun_lkup_result_t res = {
+ .tun_index = itp - ipsec_protect_pool,
+ .sa_index = sai,
+ };
+
+ /*
+ * The key is formed from the tunnel's destination
+ * as the packet lookup is done from the packet's source
+ */
+ if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
+ {
+ ipsec4_tunnel_key_t key = {
+ .remote_ip = itp->itp_crypto.dst.ip4.as_u32,
+ .spi = clib_host_to_net_u32 (sa->spi),
+ };
+ hash_set (im->tun4_protect_by_key, key.as_u64, res.as_u64);
+ }
+ else
+ {
+ ipsec6_tunnel_key_t key = {
+ .remote_ip = itp->itp_crypto.dst.ip6,
+ .spi = clib_host_to_net_u32 (sa->spi),
+ };
+ hash_set_mem_alloc (&im->tun6_protect_by_key, &key, res.as_u64);
+ }
+ }))
+ /* *INDENT-ON* */
+}
+
+static void
+ipsec_tun_protect_db_remove (ipsec_main_t * im,
+ const ipsec_tun_protect_t * itp)
+{
+ const ipsec_sa_t *sa;
+
+ /* *INDENT-OFF* */
+ FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
+ ({
+ if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
+ {
+ ipsec4_tunnel_key_t key = {
+ .remote_ip = itp->itp_crypto.dst.ip4.as_u32,
+ .spi = clib_host_to_net_u32 (sa->spi),
+ };
+ hash_unset (im->tun4_protect_by_key, &key);
+ }
+ else
+ {
+ ipsec6_tunnel_key_t key = {
+ .remote_ip = itp->itp_crypto.dst.ip6,
+ .spi = clib_host_to_net_u32 (sa->spi),
+ };
+ hash_unset_mem_free (&im->tun6_protect_by_key, &key);
+ }
+ }))
+ /* *INDENT-ON* */
+}
+
+static void
+ipsec_tun_protect_config (ipsec_main_t * im,
+ ipsec_tun_protect_t * itp, u32 sa_out, u32 * sas_in)
+{
+ ipsec_sa_t *sa;
+ u32 ii;
+
+ itp->itp_n_sa_in = vec_len (sas_in);
+ for (ii = 0; ii < itp->itp_n_sa_in; ii++)
+ itp->itp_in_sas[ii] = sas_in[ii];
+ itp->itp_out_sa = sa_out;
+
+ /* *INDENT-OFF* */
+ FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
+ ({
+ if (ipsec_sa_is_set_IS_TUNNEL (sa))
+ {
+ itp->itp_crypto.src = sa->tunnel_dst_addr;
+ itp->itp_crypto.dst = sa->tunnel_src_addr;
+ ipsec_sa_set_IS_PROTECT (sa);
+ itp->itp_flags |= IPSEC_PROTECT_ENCAPED;
+ }
+ else
+ {
+ itp->itp_crypto.src = itp->itp_tun.src;
+ itp->itp_crypto.dst = itp->itp_tun.dst;
+ itp->itp_flags &= ~IPSEC_PROTECT_ENCAPED;
+ }
+ }));
+ /* *INDENT-ON* */
+
+ /*
+ * add to the DB against each SA
+ */
+ ipsec_tun_protect_db_add (im, itp);
+
+ /*
+ * enable the encrypt feature for egress.
+ */
+ ipsec_tun_protect_feature_set (itp, 1);
+
+}
+
+static void
+ipsec_tun_protect_unconfig (ipsec_main_t * im, ipsec_tun_protect_t * itp)
+{
+ ipsec_sa_t *sa;
+
+ ipsec_tun_protect_feature_set (itp, 0);
+
+ /* *INDENT-OFF* */
+ FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
+ ({
+ ipsec_sa_unset_IS_PROTECT (sa);
+ }));
+ /* *INDENT-ON* */
+
+ ipsec_tun_protect_db_remove (im, itp);
+}
+
+index_t
+ipsec_tun_protect_find (u32 sw_if_index)
+{
+ if (vec_len (ipsec_protect_db.tunnels) < sw_if_index)
+ return (INDEX_INVALID);
+
+ return (ipsec_protect_db.tunnels[sw_if_index]);
+}
+
+int
+ipsec_tun_protect_update (u32 sw_if_index, u32 sa_out, u32 * sas_in)
+{
+ u32 itpi, ii;
+ ipsec_tun_protect_t *itp;
+ ipsec_main_t *im;
+ int rv;
+
+ rv = 0;
+ im = &ipsec_main;
+ vec_validate_init_empty (ipsec_protect_db.tunnels, sw_if_index,
+ INDEX_INVALID);
+ itpi = ipsec_protect_db.tunnels[sw_if_index];
+
+ vec_foreach_index (ii, sas_in)
+ {
+ sas_in[ii] = ipsec_get_sa_index_by_sa_id (sas_in[ii]);
+ if (~0 == sas_in[ii])
+ {
+ rv = VNET_API_ERROR_INVALID_VALUE;
+ goto out;
+ }
+ }
+
+ sa_out = ipsec_get_sa_index_by_sa_id (sa_out);
+
+ if (~0 == sa_out)
+ {
+ rv = VNET_API_ERROR_INVALID_VALUE;
+ goto out;
+ }
+
+ if (INDEX_INVALID == itpi)
+ {
+ vnet_device_class_t *dev_class;
+ vnet_hw_interface_t *hi;
+ vnet_main_t *vnm;
+ u8 is_l2;
+
+ vnm = vnet_get_main ();
+ hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
+ dev_class = vnet_get_device_class (vnm, hi->dev_class_index);
+
+ if (NULL == dev_class->ip_tun_desc)
+ {
+ rv = VNET_API_ERROR_INVALID_SW_IF_INDEX;
+ goto out;
+ }
+
+ pool_get_zero (ipsec_protect_pool, itp);
+
+ itp->itp_sw_if_index = sw_if_index;
+ ipsec_protect_db.tunnels[sw_if_index] = itp - ipsec_protect_pool;
+ ipsec_protect_db.count++;
+
+ itp->itp_n_sa_in = vec_len (sas_in);
+ for (ii = 0; ii < itp->itp_n_sa_in; ii++)
+ itp->itp_in_sas[ii] = sas_in[ii];
+ itp->itp_out_sa = sa_out;
+
+ rv = dev_class->ip_tun_desc (sw_if_index,
+ &itp->itp_tun.src,
+ &itp->itp_tun.dst, &is_l2);
+
+ if (rv)
+ goto out;
+
+ if (is_l2)
+ itp->itp_flags |= IPSEC_PROTECT_L2;
+
+ /*
+ * add to the tunnel DB for ingress
+ * - if the SA is in trasnport mode, then the packates will arrivw
+ * with the IP src,dst of the protected tunnel, in which case we can
+ * simply strip the IP header and hand the payload to the protocol
+ * appropriate input handler
+ * - if the SA is in tunnel mode then there are two IP headers present
+ * one for the crytpo tunnel endpoints (described in the SA) and one
+ * for the tunnel endpoints. The outer IP headers in the srriving
+ * packets will have the crypto endpoints. So the DB needs to contain
+ * the crpto endpoint. Once the crypto header is stripped, revealing,
+ * the tunnel-IP we have 2 choices:
+ * 1) do a tunnel lookup based on the revealed header
+ * 2) skip the tunnel lookup and assume that the packet matches the
+ * one that is protected here.
+ * If we did 1) then we would allow our peer to use the SA for tunnel
+ * X to inject traffic onto tunnel Y, this is not good. If we do 2)
+ * then we don't verify that the peer is indeed using SA for tunnel
+ * X and addressing tunnel X. So we take a compromise, once the SA
+ * matches to tunnel X we veriy that the inner IP matches the value
+ * of the tunnel we are protecting, else it's dropped.
+ */
+ ipsec_tun_protect_config (im, itp, sa_out, sas_in);
+
+ if (1 == hash_elts (im->tun4_protect_by_key))
+ ip4_register_protocol (IP_PROTOCOL_IPSEC_ESP,
+ ipsec4_tun_input_node.index);
+ if (1 == hash_elts (im->tun6_protect_by_key))
+ ip6_register_protocol (IP_PROTOCOL_IPSEC_ESP,
+ ipsec6_tun_input_node.index);
+ }
+ else
+ {
+ /* updating SAs only */
+ itp = pool_elt_at_index (ipsec_protect_pool, itpi);
+
+ ipsec_tun_protect_unconfig (im, itp);
+ ipsec_tun_protect_config (im, itp, sa_out, sas_in);
+ }
+
+ vec_free (sas_in);
+out:
+ return (rv);
+}
+
+int
+ipsec_tun_protect_del (u32 sw_if_index)
+{
+ ipsec_tun_protect_t *itp;
+ ipsec_main_t *im;
+ index_t itpi;
+
+ im = &ipsec_main;
+
+ vec_validate_init_empty (ipsec_protect_db.tunnels, sw_if_index,
+ INDEX_INVALID);
+ itpi = ipsec_protect_db.tunnels[sw_if_index];
+
+ if (INDEX_INVALID == itpi)
+ return (VNET_API_ERROR_NO_SUCH_ENTRY);
+
+ itp = ipsec_tun_protect_get (itpi);
+ ipsec_tun_protect_unconfig (im, itp);
+
+ ipsec_protect_db.tunnels[itp->itp_sw_if_index] = INDEX_INVALID;
+
+ pool_put (ipsec_protect_pool, itp);
+
+ /* if (0 == hash_elts (im->tun4_protect_by_key)) */
+ /* ip4_unregister_protocol (IP_PROTOCOL_IPSEC_ESP); */
+ /* if (0 == hash_elts (im->tun6_protect_by_key)) */
+ /* ip6_unregister_protocol (IP_PROTOCOL_IPSEC_ESP); */
+
+ return (0);
+}
+
+void
+ipsec_tun_protect_walk (ipsec_tun_protect_walk_cb_t fn, void *ctx)
+{
+ index_t itpi;
+
+ /* *INDENT-OFF* */
+ pool_foreach_index(itpi, ipsec_protect_pool,
+ ({
+ fn (itpi, ctx);
+ }));
+ /* *INDENT-ON* */
+}
+
+clib_error_t *
+ipsec_tunnel_protect_init (vlib_main_t * vm)
+{
+ ipsec_main_t *im;
+
+ im = &ipsec_main;
+ im->tun6_protect_by_key = hash_create_mem (0,
+ sizeof (ipsec6_tunnel_key_t),
+ sizeof (u64));
+ im->tun4_protect_by_key = hash_create (0, sizeof (u64));
+
+ return 0;
+}
+
+VLIB_INIT_FUNCTION (ipsec_tunnel_protect_init);
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */