ipsec: User can choose the UDP source port

Type: feature

thus allowing NAT traversal,

Signed-off-by: Neale Ranns <nranns@cisco.com>
Change-Id: Ie8650ceeb5074f98c68d2d90f6adc2f18afeba08
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>

9 files changed, 110 insertions, 24 deletions

diff --git a/src/vnet/ipsec/ipsec.c b/src/vnet/ipsec/ipsec.c
index 95e322e87a6..0ef90673596 100644
--- a/src/vnet/ipsec/ipsec.c
+++ b/src/vnet/ipsec/ipsec.c
@@ -124,6 +124,61 @@ ipsec_add_node (vlib_main_t * vm, const char *node_name,
   *out_next_index = vlib_node_add_next (vm, prev_node->index, node->index);
 }
 
+void
+ipsec_add_feature (const char *arc_name,
+		   const char *node_name, u32 * out_feature_index)
+{
+  u8 arc;
+
+  arc = vnet_get_feature_arc_index (arc_name);
+  ASSERT (arc != (u8) ~ 0);
+  *out_feature_index = vnet_get_feature_index (arc, node_name);
+}
+
+void
+ipsec_unregister_udp_port (u16 port)
+{
+  ipsec_main_t *im = &ipsec_main;
+  u32 n_regs;
+  uword *p;
+
+  p = hash_get (im->udp_port_registrations, port);
+
+  ASSERT (p);
+
+  n_regs = p[0];
+
+  if (0 == --n_regs)
+    {
+      udp_unregister_dst_port (vlib_get_main (), port, 1);
+      hash_unset (im->udp_port_registrations, port);
+    }
+  else
+    {
+      hash_unset (im->udp_port_registrations, port);
+      hash_set (im->udp_port_registrations, port, n_regs);
+    }
+}
+
+void
+ipsec_register_udp_port (u16 port)
+{
+  ipsec_main_t *im = &ipsec_main;
+  u32 n_regs;
+  uword *p;
+
+  p = hash_get (im->udp_port_registrations, port);
+
+  n_regs = (p ? p[0] : 0);
+
+  if (0 == n_regs++)
+    udp_register_dst_port (vlib_get_main (), port,
+			   ipsec4_tun_input_node.index, 1);
+
+  hash_unset (im->udp_port_registrations, port);
+  hash_set (im->udp_port_registrations, port, n_regs);
+}
+
 u32
 ipsec_register_ah_backend (vlib_main_t * vm, ipsec_main_t * im,
 			   const char *name,
diff --git a/src/vnet/ipsec/ipsec.h b/src/vnet/ipsec/ipsec.h
index 7646ffb2ddd..603bc33ba4d 100644
--- a/src/vnet/ipsec/ipsec.h
+++ b/src/vnet/ipsec/ipsec.h
@@ -108,6 +108,9 @@ typedef struct
   /* pool of policies */
   ipsec_policy_t *policies;
 
+  /* hash tables of UDP port registrations */
+  uword *udp_port_registrations;
+
   uword *tunnel_index_by_key;
 
   /* convenience */
@@ -225,8 +228,8 @@ extern vlib_node_registration_t esp4_encrypt_tun_node;
 extern vlib_node_registration_t esp6_encrypt_tun_node;
 extern vlib_node_registration_t esp4_decrypt_tun_node;
 extern vlib_node_registration_t esp6_decrypt_tun_node;
-extern vlib_node_registration_t ipsec4_if_input_node;
-extern vlib_node_registration_t ipsec6_if_input_node;
+extern vlib_node_registration_t ipsec4_tun_input_node;
+extern vlib_node_registration_t ipsec6_tun_input_node;
 
 /*
  * functions
@@ -284,6 +287,13 @@ ipsec_sa_get (u32 sa_index)
   return (pool_elt_at_index (ipsec_main.sad, sa_index));
 }
 
+void ipsec_add_feature (const char *arc_name, const char *node_name,
+			u32 * out_feature_index);
+
+void ipsec_set_async_mode (u32 is_enabled);
+extern void ipsec_register_udp_port (u16 udp_port);
+extern void ipsec_unregister_udp_port (u16 udp_port);
+
 #endif /* __IPSEC_H__ */
 
 /*
diff --git a/src/vnet/ipsec/ipsec_api.c b/src/vnet/ipsec/ipsec_api.c
index 4a55a29c288..ad2665a250c 100644
--- a/src/vnet/ipsec/ipsec_api.c
+++ b/src/vnet/ipsec/ipsec_api.c
@@ -374,7 +374,8 @@ static void vl_api_ipsec_sad_entry_add_del_t_handler
 				crypto_alg, &crypto_key,
 				integ_alg, &integ_key, flags,
 				0, mp->entry.salt, &tun_src, &tun_dst,
-				&sa_index, IPSEC_UDP_PORT_NONE);
+				&sa_index, htons (mp->entry.udp_src_port),
+				htons (mp->entry.udp_dst_port));
   else
     rv = ipsec_sa_unlock_id (id);
 
@@ -665,7 +666,7 @@ vl_api_ipsec_tunnel_if_add_del_t_handler (vl_api_ipsec_tunnel_if_add_del_t *
 				  (flags | IPSEC_SA_FLAG_IS_INBOUND),
 				  ntohl (mp->tx_table_id),
 				  mp->salt, &remote_ip, &local_ip, NULL,
-				  IPSEC_UDP_PORT_NONE);
+				  IPSEC_UDP_PORT_NONE, IPSEC_UDP_PORT_NONE);
 
       if (rv)
 	goto done;
@@ -680,7 +681,7 @@ vl_api_ipsec_tunnel_if_add_del_t_handler (vl_api_ipsec_tunnel_if_add_del_t *
 				  flags,
 				  ntohl (mp->tx_table_id),
 				  mp->salt, &local_ip, &remote_ip, NULL,
-				  IPSEC_UDP_PORT_NONE);
+				  IPSEC_UDP_PORT_NONE, IPSEC_UDP_PORT_NONE);
 
       if (rv)
 	goto done;
@@ -816,6 +817,11 @@ send_ipsec_sa_details (ipsec_sa_t * sa, void *arg)
       ip_address_encode (&sa->tunnel_dst_addr, IP46_TYPE_ANY,
 			 &mp->entry.tunnel_dst);
     }
+  if (ipsec_sa_is_set_UDP_ENCAP (sa))
+    {
+      mp->entry.udp_src_port = sa->udp_hdr.src_port;
+      mp->entry.udp_dst_port = sa->udp_hdr.dst_port;
+    }
 
   mp->seq_outbound = clib_host_to_net_u64 (((u64) sa->seq));
   mp->last_seq_inbound = clib_host_to_net_u64 (((u64) sa->last_seq));
diff --git a/src/vnet/ipsec/ipsec_cli.c b/src/vnet/ipsec/ipsec_cli.c
index 13f9efdf566..695e5f01c74 100644
--- a/src/vnet/ipsec/ipsec_cli.c
+++ b/src/vnet/ipsec/ipsec_cli.c
@@ -86,7 +86,8 @@ ipsec_sa_add_del_command_fn (vlib_main_t * vm,
   clib_error_t *error;
   ipsec_key_t ck = { 0 };
   ipsec_key_t ik = { 0 };
-  u32 id, spi, salt;
+  u32 id, spi, salt, sai;
+  u16 udp_src, udp_dst;
   int is_add, rv;
 
   salt = 0;
@@ -96,6 +97,7 @@ ipsec_sa_add_del_command_fn (vlib_main_t * vm,
   proto = IPSEC_PROTOCOL_ESP;
   integ_alg = IPSEC_INTEG_ALG_NONE;
   crypto_alg = IPSEC_CRYPTO_ALG_NONE;
+  udp_src = udp_dst = IPSEC_UDP_PORT_NONE;
 
   if (!unformat_user (input, unformat_line_input, line_input))
     return 0;
@@ -149,8 +151,7 @@ ipsec_sa_add_del_command_fn (vlib_main_t * vm,
     rv = ipsec_sa_add_and_lock (id, spi, proto, crypto_alg,
 				&ck, integ_alg, &ik, flags,
 				0, clib_host_to_net_u32 (salt),
-				&tun_src, &tun_dst, NULL,
-				IPSEC_UDP_PORT_NONE);
+				&tun_src, &tun_dst, &sai, udp_src, udp_dst);
   else
     rv = ipsec_sa_unlock_id (id);
 
@@ -856,14 +857,16 @@ create_ipsec_tunnel_command_fn (vlib_main_t * vm,
 			       local_spi, IPSEC_PROTOCOL_ESP, crypto_alg,
 			       &lck, integ_alg, &lik, flags, table_id,
 			       clib_host_to_net_u32 (salt), &local_ip,
-			       &remote_ip, NULL, IPSEC_UDP_PORT_NONE);
+			       &remote_ip, NULL, IPSEC_UDP_PORT_NONE,
+			       IPSEC_UDP_PORT_NONE);
       rv |=
 	ipsec_sa_add_and_lock (ipsec_tun_mk_remote_sa_id (sw_if_index),
 			       remote_spi, IPSEC_PROTOCOL_ESP, crypto_alg,
 			       &rck, integ_alg, &rik,
 			       (flags | IPSEC_SA_FLAG_IS_INBOUND), table_id,
 			       clib_host_to_net_u32 (salt), &remote_ip,
-			       &local_ip, NULL, IPSEC_UDP_PORT_NONE);
+			       &local_ip, NULL, IPSEC_UDP_PORT_NONE,
+			       IPSEC_UDP_PORT_NONE);
       rv |=
 	ipsec_tun_protect_update_one (sw_if_index, &nh,
 				      ipsec_tun_mk_local_sa_id (sw_if_index),
diff --git a/src/vnet/ipsec/ipsec_format.c b/src/vnet/ipsec/ipsec_format.c
index bf398cb2105..98de779b0de 100644
--- a/src/vnet/ipsec/ipsec_format.c
+++ b/src/vnet/ipsec/ipsec_format.c
@@ -310,6 +310,9 @@ format_ipsec_sa (u8 * s, va_list * args)
     s = format (s, " key %U", format_ipsec_key, &sa->integ_key);
   else
     s = format (s, " key [redacted]");
+  s = format (s, "\n   UDP:[src:%d dst:%d]",
+	      clib_host_to_net_u16 (sa->udp_hdr.src_port),
+	      clib_host_to_net_u16 (sa->udp_hdr.dst_port));
 
   vlib_get_combined_counter (&ipsec_sa_counters, sai, &counts);
   s = format (s, "\n   packets %u bytes %u", counts.packets, counts.bytes);
diff --git a/src/vnet/ipsec/ipsec_sa.c b/src/vnet/ipsec/ipsec_sa.c
index f60566cba79..e5f01bff0d9 100644
--- a/src/vnet/ipsec/ipsec_sa.c
+++ b/src/vnet/ipsec/ipsec_sa.c
@@ -179,7 +179,7 @@ ipsec_sa_add_and_lock (u32 id,
 		       u32 salt,
 		       const ip46_address_t * tun_src,
 		       const ip46_address_t * tun_dst, u32 * sa_out_index,
-		       u16 dst_port)
+		       u16 src_port, u16 dst_port)
 {
   vlib_main_t *vm = vlib_get_main ();
   ipsec_main_t *im = &ipsec_main;
@@ -329,15 +329,17 @@ ipsec_sa_add_and_lock (u32 id,
   if (ipsec_sa_is_set_UDP_ENCAP (sa))
     {
       if (dst_port == IPSEC_UDP_PORT_NONE)
-	{
-	  sa->udp_hdr.src_port = clib_host_to_net_u16 (UDP_DST_PORT_ipsec);
-	  sa->udp_hdr.dst_port = clib_host_to_net_u16 (UDP_DST_PORT_ipsec);
-	}
+	sa->udp_hdr.dst_port = clib_host_to_net_u16 (UDP_DST_PORT_ipsec);
       else
-	{
-	  sa->udp_hdr.src_port = clib_host_to_net_u16 (dst_port);
-	  sa->udp_hdr.dst_port = clib_host_to_net_u16 (dst_port);
-	}
+	sa->udp_hdr.dst_port = clib_host_to_net_u16 (dst_port);
+
+      if (src_port == IPSEC_UDP_PORT_NONE)
+	sa->udp_hdr.src_port = clib_host_to_net_u16 (UDP_DST_PORT_ipsec);
+      else
+	sa->udp_hdr.src_port = clib_host_to_net_u16 (src_port);
+
+      if (ipsec_sa_is_set_IS_INBOUND (sa))
+	ipsec_register_udp_port (clib_host_to_net_u16 (sa->udp_hdr.dst_port));
     }
 
   hash_set (im->sa_index_by_sa_id, sa->id, sa_index);
@@ -361,6 +363,9 @@ ipsec_sa_del (ipsec_sa_t * sa)
   /* no recovery possible when deleting an SA */
   (void) ipsec_call_add_del_callbacks (im, sa, sa_index, 0);
 
+  if (ipsec_sa_is_set_UDP_ENCAP (sa) && ipsec_sa_is_set_IS_INBOUND (sa))
+    ipsec_unregister_udp_port (clib_net_to_host_u16 (sa->udp_hdr.dst_port));
+
   if (ipsec_sa_is_set_IS_TUNNEL (sa) && !ipsec_sa_is_set_IS_INBOUND (sa))
     {
       fib_entry_untrack (sa->fib_entry_index, sa->sibling);
diff --git a/src/vnet/ipsec/ipsec_sa.h b/src/vnet/ipsec/ipsec_sa.h
index de9b51ea66a..5950d6f53b3 100644
--- a/src/vnet/ipsec/ipsec_sa.h
+++ b/src/vnet/ipsec/ipsec_sa.h
@@ -250,7 +250,7 @@ extern int ipsec_sa_add_and_lock (u32 id,
 				  u32 salt,
 				  const ip46_address_t * tunnel_src_addr,
 				  const ip46_address_t * tunnel_dst_addr,
-				  u32 * sa_index, u16 dst_port);
+				  u32 * sa_index, u16 src_port, u16 dst_port);
 extern index_t ipsec_sa_find_and_lock (u32 id);
 extern int ipsec_sa_unlock_id (u32 id);
 extern void ipsec_sa_unlock (index_t sai);
diff --git a/src/vnet/ipsec/ipsec_tun.c b/src/vnet/ipsec/ipsec_tun.c
index a93e66a8775..9b76d311bc2 100644
--- a/src/vnet/ipsec/ipsec_tun.c
+++ b/src/vnet/ipsec/ipsec_tun.c
@@ -91,9 +91,7 @@ ipsec_tun_register_nodes (ip_address_family_t af)
     {
       if (AF_IP4 == af)
 	{
-	  udp_register_dst_port (vlib_get_main (),
-				 UDP_DST_PORT_ipsec,
-				 ipsec4_tun_input_node.index, 1);
+	  ipsec_register_udp_port (UDP_DST_PORT_ipsec);
 	  ip4_register_protocol (IP_PROTOCOL_IPSEC_ESP,
 				 ipsec4_tun_input_node.index);
 	}
@@ -111,7 +109,7 @@ ipsec_tun_unregister_nodes (ip_address_family_t af)
     {
       if (AF_IP4 == af)
 	{
-	  udp_unregister_dst_port (vlib_get_main (), UDP_DST_PORT_ipsec, 1);
+	  ipsec_unregister_udp_port (UDP_DST_PORT_ipsec);
 	  ip4_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
 	}
       else
diff --git a/src/vnet/ipsec/ipsec_types.api b/src/vnet/ipsec/ipsec_types.api
index f393fc879b9..715f3de0e12 100644
--- a/src/vnet/ipsec/ipsec_types.api
+++ b/src/vnet/ipsec/ipsec_types.api
@@ -104,6 +104,10 @@ typedef key
     @param tunnel_dst_address - IPsec tunnel destination address IPv6 if is_tunnel_ipv6 is non-zero, else IPv4. Only valid if is_tunnel is non-zero
     @param tx_table_id - the FIB id used for encapsulated packets
     @param salt - for use with counter mode ciphers
+    @param udp_src_port - If using UDP Encapsulation, use this source port for
+                          TX. It is ignored for RX.
+    @param udp_dst_port - If using UDP Encapsulation, use this destination port
+                          for TX. Expect traffic on this port for RX.
  */
 typedef ipsec_sad_entry
 {
@@ -125,6 +129,8 @@ typedef ipsec_sad_entry
   vl_api_address_t tunnel_dst;
   u32 tx_table_id;
   u32 salt;
+  u16 udp_src_port [default=4500];
+  u16 udp_dst_port [default=4500];
 };
 
 /*