commit 4f4f271850b03dd4f9932a29c4bb7aba8ed76e5e
author Neil Armstrong <narmstrong@baylibre.com> Thu May 05 15:34:39 2022 +0200
committer Neil Armstrong <narmstrong@baylibre.com> Wed May 18 13:19:29 2022 +0200
tree 025a1ac9dad51f8db9b5f88f1e3345390adc6c4e
parent a8093f5c48a15dfe5acfb72ab8e2898284f88ad0

In mbedtls_ssl_tls13_generate_handshake_keys() and mbedtls_ssl_tls13_generate_application_keys(), avoid calling mbedtls_cipher_info_from_type()

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

library/ssl_tls13_keys.c

diff --git a/library/ssl_tls13_keys.c b/library/ssl_tls13_keys.c
index c79d4c9..714c21a 100644
--- a/library/ssl_tls13_keys.c
+++ b/library/ssl_tls13_keys.c
@@ -1203,7 +1203,15 @@
     unsigned char transcript[MBEDTLS_TLS1_3_MD_MAX_SIZE];
     size_t transcript_len;
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    psa_key_type_t key_type;
+    psa_algorithm_t alg;
+    size_t key_bits;
+    size_t taglen;
+    psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
+#else
     mbedtls_cipher_info_t const *cipher_info;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
     size_t key_len, iv_len;
 
     mbedtls_ssl_handshake_params *handshake = ssl->handshake;
@@ -1212,9 +1220,32 @@
 
     MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> mbedtls_ssl_tls13_generate_handshake_keys" ) );
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    if( ciphersuite_info->flags & MBEDTLS_CIPHERSUITE_SHORT_TAG )
+        taglen = 8;
+    else
+        taglen = 16;
+
+    status = mbedtls_ssl_cipher_to_psa( ciphersuite_info->cipher, taglen,
+                                        &alg, &key_type, &key_bits );
+    if( status != PSA_SUCCESS )
+    {
+        ret = psa_ssl_status_to_mbedtls( status );
+        MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_cipher_to_psa", ret );
+        return ret;
+    }
+
+    key_len = PSA_BITS_TO_BYTES(key_bits);
+
+    if( PSA_ALG_IS_AEAD( alg ) )
+        iv_len = 12;
+    else
+        iv_len = PSA_CIPHER_IV_LENGTH( key_type, alg );
+#else
     cipher_info = mbedtls_cipher_info_from_type( ciphersuite_info->cipher );
     key_len = cipher_info->key_bitlen >> 3;
     iv_len = cipher_info->iv_size;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
 
     md_type = ciphersuite_info->mac;
 
@@ -1408,17 +1439,48 @@
     size_t hash_len;
 
     /* Variables relating to the cipher for the chosen ciphersuite. */
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    psa_key_type_t key_type;
+    psa_algorithm_t alg;
+    size_t key_bits;
+    size_t taglen;
+    psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
+#else
     mbedtls_cipher_info_t const *cipher_info;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
     size_t key_len, iv_len;
 
     MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> derive application traffic keys" ) );
 
     /* Extract basic information about hash and ciphersuite */
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    if( handshake->ciphersuite_info->flags & MBEDTLS_CIPHERSUITE_SHORT_TAG )
+        taglen = 8;
+    else
+        taglen = 16;
+
+    status = mbedtls_ssl_cipher_to_psa( handshake->ciphersuite_info->cipher,
+                                        taglen, &alg, &key_type, &key_bits );
+    if( status != PSA_SUCCESS )
+    {
+        ret = psa_ssl_status_to_mbedtls( status );
+        MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_cipher_to_psa", ret );
+        goto cleanup;
+    }
+
+    key_len = PSA_BITS_TO_BYTES(key_bits);
+
+    if( PSA_ALG_IS_AEAD( alg ) )
+        iv_len = 12;
+    else
+        iv_len = PSA_CIPHER_IV_LENGTH( key_type, alg );
+#else
     cipher_info = mbedtls_cipher_info_from_type(
                                   handshake->ciphersuite_info->cipher );
     key_len = cipher_info->key_bitlen / 8;
     iv_len = cipher_info->iv_size;
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
 
     md_type = handshake->ciphersuite_info->mac;