IPSEC: Pass the algorithm salt (used in GCM) over the API

Change-Id: Ia8cea13f7b937294e6a080a55fb2ceff30063acf
Signed-off-by: Neale Ranns <nranns@cisco.com>

6 files changed, 16 insertions, 10 deletions

diff --git a/src/vnet/ipsec/esp_decrypt.c b/src/vnet/ipsec/esp_decrypt.c
index d2365fce2d8..e74c1bb908a 100644
--- a/src/vnet/ipsec/esp_decrypt.c
+++ b/src/vnet/ipsec/esp_decrypt.c
@@ -239,7 +239,6 @@ esp_decrypt_inline (vlib_main_t * vm,
 	      esp_header_t *esp0;
 	      esp_aead_t *aad;
 	      u8 *scratch;
-	      u32 salt;
 
 	      /*
 	       * construct the AAD and the nonce (Salt || IV) in a scratch
@@ -258,9 +257,8 @@ esp_decrypt_inline (vlib_main_t * vm,
 	       * can overwrite it with the salt and use the IV where it is
 	       * to form the nonce = (Salt + IV)
 	       */
-	      salt = clib_host_to_net_u32 (sa0->salt);
 	      op->iv -= sizeof (sa0->salt);
-	      clib_memcpy_fast (op->iv, &salt, sizeof (sa0->salt));
+	      clib_memcpy_fast (op->iv, &sa0->salt, sizeof (sa0->salt));
 	      op->iv_len = cpd.iv_sz + sizeof (sa0->salt);
 
 	      op->tag = payload + len;
diff --git a/src/vnet/ipsec/ipsec.api b/src/vnet/ipsec/ipsec.api
index bc407f1d272..3a2c993f99c 100644
--- a/src/vnet/ipsec/ipsec.api
+++ b/src/vnet/ipsec/ipsec.api
@@ -262,6 +262,7 @@ typedef key
     @param tunnel_src_address - IPsec tunnel source address IPv6 if is_tunnel_ipv6 is non-zero, else IPv4. Only valid if is_tunnel is non-zero
     @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
  */
 typedef ipsec_sad_entry
 {
@@ -282,6 +283,7 @@ typedef ipsec_sad_entry
   vl_api_address_t tunnel_src;
   vl_api_address_t tunnel_dst;
   u32 tx_table_id;
+  u32 salt;
 };
 
 /** \brief IPsec: Add/delete Security Association Database entry
@@ -374,6 +376,7 @@ define ipsec_spd_interface_details {
     @param show_instance - instance to display for intf if renumber is set
     @param udp_encap - enable UDP encapsulation for NAT traversal
     @param tx_table_id - the FIB id used after packet encap
+    @param salt - for use with counter mode ciphers
 */
 define ipsec_tunnel_if_add_del {
   u32 client_index;
@@ -399,6 +402,7 @@ define ipsec_tunnel_if_add_del {
   u32 show_instance;
   u8 udp_encap;
   u32 tx_table_id;
+  u32 salt;
 };
 
 /** \brief Add/delete IPsec tunnel interface response
diff --git a/src/vnet/ipsec/ipsec_api.c b/src/vnet/ipsec/ipsec_api.c
index 767cd2fb076..4a15beb6631 100644
--- a/src/vnet/ipsec/ipsec_api.c
+++ b/src/vnet/ipsec/ipsec_api.c
@@ -385,12 +385,11 @@ static void vl_api_ipsec_sad_entry_add_del_t_handler
   ip_address_decode (&mp->entry.tunnel_src, &tun_src);
   ip_address_decode (&mp->entry.tunnel_dst, &tun_dst);
 
-
   if (mp->is_add)
     rv = ipsec_sa_add (id, spi, proto,
 		       crypto_alg, &crypto_key,
 		       integ_alg, &integ_key, flags,
-		       0, 0, &tun_src, &tun_dst, &sa_index);
+		       0, mp->entry.salt, &tun_src, &tun_dst, &sa_index);
   else
     rv = ipsec_sa_del (id);
 
@@ -644,6 +643,7 @@ vl_api_ipsec_tunnel_if_add_del_t_handler (vl_api_ipsec_tunnel_if_add_del_t *
   tun.remote_integ_key_len = mp->remote_integ_key_len;
   tun.udp_encap = mp->udp_encap;
   tun.tx_table_id = ntohl (mp->tx_table_id);
+  tun.salt = mp->salt;
   itype = ip_address_decode (&mp->local_ip, &tun.local_ip);
   itype = ip_address_decode (&mp->remote_ip, &tun.remote_ip);
   tun.is_ip6 = (IP46_TYPE_IP6 == itype);
diff --git a/src/vnet/ipsec/ipsec_cli.c b/src/vnet/ipsec/ipsec_cli.c
index 096060865e9..b6bdc40fd1a 100644
--- a/src/vnet/ipsec/ipsec_cli.c
+++ b/src/vnet/ipsec/ipsec_cli.c
@@ -84,8 +84,8 @@ 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;
   int is_add, rv;
-  u32 id, spi;
 
   error = NULL;
   is_add = 0;
@@ -103,6 +103,8 @@ ipsec_sa_add_del_command_fn (vlib_main_t * vm,
 	is_add = 0;
       else if (unformat (line_input, "spi %u", &spi))
 	;
+      else if (unformat (line_input, "salt %u", &salt))
+	;
       else if (unformat (line_input, "esp"))
 	proto = IPSEC_PROTOCOL_ESP;
       else if (unformat (line_input, "ah"))
@@ -141,7 +143,8 @@ ipsec_sa_add_del_command_fn (vlib_main_t * vm,
   if (is_add)
     rv = ipsec_sa_add (id, spi, proto, crypto_alg,
 		       &ck, integ_alg, &ik, flags,
-		       0, 0, &tun_src, &tun_dst, NULL);
+		       0, clib_host_to_net_u32 (salt),
+		       &tun_src, &tun_dst, NULL);
   else
     rv = ipsec_sa_del (id);
 
diff --git a/src/vnet/ipsec/ipsec_format.c b/src/vnet/ipsec/ipsec_format.c
index 93b1efd6902..44f064d6112 100644
--- a/src/vnet/ipsec/ipsec_format.c
+++ b/src/vnet/ipsec/ipsec_format.c
@@ -290,7 +290,7 @@ format_ipsec_sa (u8 * s, va_list * args)
   if (!(flags & IPSEC_FORMAT_DETAIL))
     goto done;
 
-  s = format (s, "\n   salt 0x%x", sa->salt);
+  s = format (s, "\n   salt 0x%x", clib_net_to_host_u32 (sa->salt));
   s = format (s, "\n   seq %u seq-hi %u", sa->seq, sa->seq_hi);
   s = format (s, "\n   last-seq %u last-seq-hi %u window %U",
 	      sa->last_seq, sa->last_seq_hi,
@@ -303,6 +303,7 @@ format_ipsec_sa (u8 * s, va_list * args)
 	      format_ipsec_integ_alg, sa->integ_alg);
   if (sa->integ_alg)
     s = format (s, " key %U", format_ipsec_key, &sa->integ_key);
+
   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.h b/src/vnet/ipsec/ipsec_sa.h
index f87e12e0204..d1b44c3165f 100644
--- a/src/vnet/ipsec/ipsec_sa.h
+++ b/src/vnet/ipsec/ipsec_sa.h
@@ -160,9 +160,9 @@ typedef struct
   u32 sibling;
 
   u32 tx_fib_index;
-  u32 salt;
 
-  /* runtime */
+  /* Salt used in GCM modes - stored in network byte order */
+  u32 salt;
 } ipsec_sa_t;
 
 STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline1, CLIB_CACHE_LINE_BYTES);