ipsec: add support for RFC-4543 ENCR_NULL_AUTH_AES_GMAC

[vpp.git] / src / vnet / ipsec / esp_encrypt.c

diff --git a/src/vnet/ipsec/esp_encrypt.c b/src/vnet/ipsec/esp_encrypt.c
index 86f9094..a836453 100644 (file)
--- a/src/vnet/ipsec/esp_encrypt.c
+++ b/src/vnet/ipsec/esp_encrypt.c
@@ -415,6 +415,12 @@ esp_prepare_sync_op (vlib_main_t *vm, ipsec_per_thread_data_t *ptd,
              op->aad_len = esp_aad_fill (op->aad, esp, sa0, seq_hi);
              op->tag = payload + crypto_len;
              op->tag_len = 16;
+             if (PREDICT_FALSE (ipsec_sa_is_set_IS_NULL_GMAC (sa0)))
+               {
+                 /* RFC-4543 ENCR_NULL_AUTH_AES_GMAC: IV is part of AAD */
+                 crypto_start -= iv_sz;
+                 crypto_len += iv_sz;
+               }
            }
          else
            {
@@ -522,6 +528,12 @@ esp_prepare_async_frame (vlib_main_t *vm, ipsec_per_thread_data_t *ptd,
          /* constuct aad in a scratch space in front of the nonce */
          aad = (u8 *) nonce - sizeof (esp_aead_t);
          esp_aad_fill (aad, esp, sa, sa->seq_hi);
+         if (PREDICT_FALSE (ipsec_sa_is_set_IS_NULL_GMAC (sa)))
+           {
+             /* RFC-4543 ENCR_NULL_AUTH_AES_GMAC: IV is part of AAD */
+             crypto_start_offset -= iv_sz;
+             crypto_total_len += iv_sz;
+           }
        }
       else
        {