ssl_parse_client_key_exchange(): read the curve identifier and the peer's public key and compute the shared secret using PSA
Signed-off-by: Przemek Stekiel <przemyslaw.stekiel@mobica.com>
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 50715b5..55d7802 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -3878,6 +3878,56 @@
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_RSA ||
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 )
+ {
+ 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
if( ( ret = mbedtls_ecdh_read_public( &ssl->handshake->ecdh_ctx,
p, end - p) ) != 0 )
{
@@ -3900,6 +3950,7 @@
MBEDTLS_SSL_DEBUG_ECDH( 3, &ssl->handshake->ecdh_ctx,
MBEDTLS_DEBUG_ECDH_Z );
+#endif
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||