Remove cipher_info in ssl_tls12_populate_transform() when USE_PSA_CRYPTO is defined

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>

library/ssl_tls.c

@@ -6911,9 +6911,9 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
     size_t iv_copy_len;
     size_t keylen;
     const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
-    const mbedtls_cipher_info_t *cipher_info;
     mbedtls_ssl_mode_t ssl_mode;
 #if !defined(MBEDTLS_USE_PSA_CRYPTO)
+    const mbedtls_cipher_info_t *cipher_info;
     const mbedtls_md_info_t *md_info;
 #endif /* !MBEDTLS_USE_PSA_CRYPTO */
 
@@ -6974,6 +6974,22 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
 #endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
                                         ciphersuite_info );
 
+    if( ssl_mode == MBEDTLS_SSL_MODE_AEAD )
+        transform->taglen =
+            ciphersuite_info->flags & MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
+
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    if( ( status = mbedtls_ssl_cipher_to_psa( ciphersuite_info->cipher,
+                                 transform->taglen,
+                                 &alg,
+                                 &key_type,
+                                 &key_bits ) ) != PSA_SUCCESS )
+    {
+        ret = psa_ssl_status_to_mbedtls( status );
+        MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_cipher_to_psa", ret );
+        goto end;
+    }
+#else
     cipher_info = mbedtls_cipher_info_from_type( ciphersuite_info->cipher );
     if( cipher_info == NULL )
     {
@@ -6981,6 +6997,7 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
                                     ciphersuite_info->cipher ) );
         return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
     }
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
 
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
     mac_alg = mbedtls_psa_translate_md( ciphersuite_info->mac );
@@ -7040,7 +7057,11 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
      * Determine the appropriate key, IV and MAC length.
      */
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    keylen = PSA_BITS_TO_BYTES(key_bits);
+#else
     keylen = mbedtls_cipher_info_get_key_bitlen( cipher_info ) / 8;
+#endif
 
 #if defined(MBEDTLS_GCM_C) ||                           \
     defined(MBEDTLS_CCM_C) ||                           \
@@ -7051,8 +7072,6 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
 
         transform->maclen = 0;
         mac_key_len = 0;
-        transform->taglen =
-            ciphersuite_info->flags & MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
 
         /* All modes haves 96-bit IVs, but the length of the static parts vary
          * with mode and version:
@@ -7063,7 +7082,11 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
          *   sequence number).
          */
         transform->ivlen = 12;
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+        if( key_type == PSA_KEY_TYPE_CHACHA20 )
+#else
         if( mbedtls_cipher_info_get_mode( cipher_info ) == MBEDTLS_MODE_CHACHAPOLY )
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
             transform->fixed_ivlen = 12;
         else
             transform->fixed_ivlen = 4;
@@ -7079,6 +7102,12 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
         ssl_mode == MBEDTLS_SSL_MODE_CBC ||
         ssl_mode == MBEDTLS_SSL_MODE_CBC_ETM )
     {
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+        size_t block_size = PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE;
+#else
+        size_t block_size = cipher_info->block_size;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
         /* Get MAC length */
         mac_key_len = PSA_HASH_LENGTH(mac_alg);
@@ -7097,7 +7126,14 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
         transform->maclen = mac_key_len;
 
         /* IV length */
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+        if( ssl_mode == MBEDTLS_SSL_MODE_STREAM )
+            transform->ivlen = 0;
+        else
+            transform->ivlen = PSA_CIPHER_IV_LENGTH( key_type, alg );
+#else
         transform->ivlen = cipher_info->iv_size;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
 
         /* Minimum length */
         if( ssl_mode == MBEDTLS_SSL_MODE_STREAM )
@@ -7114,14 +7150,14 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
             if( ssl_mode == MBEDTLS_SSL_MODE_CBC_ETM )
             {
                 transform->minlen = transform->maclen
-                                  + cipher_info->block_size;
+                                  + block_size;
             }
             else
 #endif
             {
                 transform->minlen = transform->maclen
-                                  + cipher_info->block_size
+                                  + block_size
-                                  - transform->maclen % cipher_info->block_size;
+                                  - transform->maclen % block_size;
             }
 
             if( tls_version == MBEDTLS_SSL_VERSION_TLS1_2 )
@@ -7203,17 +7239,6 @@ static int ssl_tls12_populate_transform( mbedtls_ssl_transform *transform,
     }
 
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
-    if( ( status = mbedtls_ssl_cipher_to_psa( cipher_info->type,
-                                 transform->taglen,
-                                 &alg,
-                                 &key_type,
-                                 &key_bits ) ) != PSA_SUCCESS )
-    {
-        ret = psa_ssl_status_to_mbedtls( status );
-        MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_cipher_to_psa", ret );
-        goto end;
-    }
-
     transform->psa_alg = alg;
 
     if ( alg != MBEDTLS_SSL_NULL_CIPHER )