Use PSA version of key agreement only for ECDHE keys
This should be cleaned when server-side static ECDH (1.2) support is added (#5320).
Signed-off-by: Przemek Stekiel <przemyslaw.stekiel@mobica.com>
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 55d7802..23fc49d 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -3879,55 +3879,86 @@
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA )
{
#if defined(MBEDTLS_USE_PSA_CRYPTO)
- size_t data_len = (size_t)( *p++ );
- size_t buf_len = (size_t)( end - p );
- psa_status_t status = PSA_ERROR_GENERIC_ERROR;
- mbedtls_ssl_handshake_params *handshake = ssl->handshake;
-
- MBEDTLS_SSL_DEBUG_MSG( 1, ( "Read the peer's public key." ) );
-
- /*
- * We must have at least two bytes (1 for length, at least 1 for data)
- */
- if( buf_len < 2 )
+ // Handle only ECDHE keys using PSA crypto.
+ if ( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
+ ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA )
{
- MBEDTLS_SSL_DEBUG_MSG( 1, ( "Invalid buffer length" ) );
- return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
- }
+ size_t data_len = (size_t)( *p++ );
+ size_t buf_len = (size_t)( end - p );
+ psa_status_t status = PSA_ERROR_GENERIC_ERROR;
+ mbedtls_ssl_handshake_params *handshake = ssl->handshake;
- if( data_len < 1 || data_len > buf_len )
+ MBEDTLS_SSL_DEBUG_MSG( 1, ( "Read the peer's public key." ) );
+
+ /*
+ * We must have at least two bytes (1 for length, at least 1 for data)
+ */
+ if( buf_len < 2 )
+ {
+ MBEDTLS_SSL_DEBUG_MSG( 1, ( "Invalid buffer length" ) );
+ return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
+ }
+
+ if( data_len < 1 || data_len > buf_len )
+ {
+ MBEDTLS_SSL_DEBUG_MSG( 1, ( "Invalid data length" ) );
+ return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
+ }
+
+ /* Store peer's ECDH public key. */
+ memcpy( handshake->ecdh_psa_peerkey, p, data_len );
+ handshake->ecdh_psa_peerkey_len = data_len;
+
+ /* Compute ECDH shared secret. */
+ status = psa_raw_key_agreement(
+ PSA_ALG_ECDH, handshake->ecdh_psa_privkey,
+ handshake->ecdh_psa_peerkey, handshake->ecdh_psa_peerkey_len,
+ handshake->premaster, sizeof( handshake->premaster ),
+ &handshake->pmslen );
+ if( status != PSA_SUCCESS )
+ {
+ ret = psa_ssl_status_to_mbedtls( status );
+ MBEDTLS_SSL_DEBUG_RET( 1, "psa_raw_key_agreement", ret );
+ return( ret );
+ }
+
+ status = psa_destroy_key( handshake->ecdh_psa_privkey );
+
+ if( status != PSA_SUCCESS )
+ {
+ ret = psa_ssl_status_to_mbedtls( status );
+ MBEDTLS_SSL_DEBUG_RET( 1, "psa_destroy_key", ret );
+ return( ret );
+ }
+ handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
+
+ }
+ else
{
- MBEDTLS_SSL_DEBUG_MSG( 1, ( "Invalid data length" ) );
- return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
+ if( ( ret = mbedtls_ecdh_read_public( &ssl->handshake->ecdh_ctx,
+ p, end - p) ) != 0 )
+ {
+ MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_read_public", ret );
+ return( MBEDTLS_ERR_SSL_DECODE_ERROR );
+ }
+
+ MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx,
+ MBEDTLS_DEBUG_ECDH_QP );
+
+ if( ( ret = mbedtls_ecdh_calc_secret( &ssl->handshake->ecdh_ctx,
+ &ssl->handshake->pmslen,
+ ssl->handshake->premaster,
+ MBEDTLS_MPI_MAX_SIZE,
+ ssl->conf->f_rng, ssl->conf->p_rng ) ) != 0 )
+ {
+ MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ecdh_calc_secret", ret );
+ return( MBEDTLS_ERR_SSL_DECODE_ERROR );
+ }
+
+ MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx,
+ MBEDTLS_DEBUG_ECDH_Z );
}
-
- /* Store peer's ECDH public key. */
- memcpy( handshake->ecdh_psa_peerkey, p, data_len );
- handshake->ecdh_psa_peerkey_len = data_len;
-
- /* Compute ECDH shared secret. */
- status = psa_raw_key_agreement(
- PSA_ALG_ECDH, handshake->ecdh_psa_privkey,
- handshake->ecdh_psa_peerkey, handshake->ecdh_psa_peerkey_len,
- handshake->premaster, sizeof( handshake->premaster ),
- &handshake->pmslen );
- if( status != PSA_SUCCESS )
- {
- ret = psa_ssl_status_to_mbedtls( status );
- MBEDTLS_SSL_DEBUG_RET( 1, "psa_raw_key_agreement", ret );
- return( ret );
- }
-
- status = psa_destroy_key( handshake->ecdh_psa_privkey );
-
- if( status != PSA_SUCCESS )
- {
- ret = psa_ssl_status_to_mbedtls( status );
- MBEDTLS_SSL_DEBUG_RET( 1, "psa_destroy_key", ret );
- return( ret );
- }
- handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
-#else
+#else /* MBEDTLS_USE_PSA_CRYPTO */
if( ( ret = mbedtls_ecdh_read_public( &ssl->handshake->ecdh_ctx,
p, end - p) ) != 0 )
{
@@ -3950,7 +3981,7 @@
MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx,
MBEDTLS_DEBUG_ECDH_Z );
-#endif
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||