crypto: fix chained buffer integrity support

[vpp.git] / src / plugins / crypto_sw_scheduler / main.c

diff --git a/src/plugins/crypto_sw_scheduler/main.c b/src/plugins/crypto_sw_scheduler/main.c
index 980fa14..fa2611f 100644 (file)
--- a/src/plugins/crypto_sw_scheduler/main.c
+++ b/src/plugins/crypto_sw_scheduler/main.c
@@ -148,8 +148,6 @@ cryptodev_sw_scheduler_sgl (vlib_main_t * vm,
   u32 n_chunks = 0;
   u32 chunk_index = vec_len (ptd->chunks);
 
-  op->flags |= VNET_CRYPTO_OP_FLAG_CHAINED_BUFFERS;
-
   while (len)
     {
       if (nb->current_data + nb->current_length > offset)
@@ -172,7 +170,21 @@ cryptodev_sw_scheduler_sgl (vlib_main_t * vm,
        break;
     }
 
-  ASSERT (offset == 0 && len == 0);
+  ASSERT (offset == 0);
+  if (n_chunks && len)
+    {
+      /* Some async crypto users can use buffers in creative ways, let's allow
+       * some flexibility here...
+       * Current example is ESP decrypt with ESN in async mode: it will stash
+       * ESN at the end of the last buffer (if it can) because it must be part
+       * of the integrity check but it will not update the buffer length.
+       * Fixup the last operation chunk length if we have room.
+       */
+      ASSERT (vlib_buffer_space_left_at_end (vm, nb) >= len);
+      if (vlib_buffer_space_left_at_end (vm, nb) >= len)
+       ch->len += len;
+    }
+
   op->chunk_index = chunk_index;
   op->n_chunks = n_chunks;
 }
@@ -251,15 +263,12 @@ crypto_sw_scheduler_convert_link_crypto (vlib_main_t * vm,
   crypto_op->iv = fe->iv;
   crypto_op->key_index = key->index_crypto;
   crypto_op->user_data = 0;
+  crypto_op->flags = fe->flags & ~VNET_CRYPTO_OP_FLAG_HMAC_CHECK;
   integ_op->op = integ_op_id;
   integ_op->digest = fe->digest;
   integ_op->digest_len = digest_len;
   integ_op->key_index = key->index_integ;
-  crypto_op->flags = integ_op->flags = 0;
-  if (is_enc)
-    crypto_op->flags |= VNET_CRYPTO_OP_FLAG_INIT_IV;
-  else
-    integ_op->flags |= VNET_CRYPTO_OP_FLAG_HMAC_CHECK;
+  integ_op->flags = fe->flags & ~VNET_CRYPTO_OP_FLAG_INIT_IV;
   crypto_op->user_data = integ_op->user_data = index;
 }