Add server-support for opaque PSKs

This commit is contained in:
Hanno Becker 2018-10-26 12:07:29 +01:00
parent 8bb28b9470
commit 4855c2d4c2

View file

@ -149,6 +149,48 @@ static int ssl_parse_servername_ext( mbedtls_ssl_context *ssl,
}
#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
static int ssl_conf_has_psk_or_cb( mbedtls_ssl_config const *conf )
{
if( conf->f_psk != NULL )
return( 1 );
if( conf->psk_identity_len == 0 || conf->psk_identity == NULL )
return( 0 );
if( conf->psk != NULL && conf->psk_len != 0 )
return( 1 );
#if defined(MBEDTLS_USE_PSA_CRYPTO)
if( conf->psk_opaque != 0 )
return( 1 );
#endif /* MBEDTLS_USE_PSA_CRYPTO */
return( 0 );
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
static int ssl_use_opaque_psk( mbedtls_ssl_context const *ssl )
{
if( ssl->conf->f_psk != NULL )
{
/* If we've used a callback to select the PSK,
* the static configuration is irrelevant. */
if( ssl->handshake->psk_opaque != 0 )
return( 1 );
return( 0 );
}
if( ssl->conf->psk_opaque != 0 )
return( 1 );
return( 0 );
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#endif /* MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED */
static int ssl_parse_renegotiation_info( mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len )
@ -867,9 +909,7 @@ static int ssl_ciphersuite_match( mbedtls_ssl_context *ssl, int suite_id,
/* If the ciphersuite requires a pre-shared key and we don't
* have one, skip it now rather than failing later */
if( mbedtls_ssl_ciphersuite_uses_psk( suite_info ) &&
ssl->conf->f_psk == NULL &&
( ssl->conf->psk == NULL || ssl->conf->psk_identity == NULL ||
ssl->conf->psk_identity_len == 0 || ssl->conf->psk_len == 0 ) )
ssl_conf_has_psk_or_cb( ssl->conf ) == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "ciphersuite mismatch: no pre-shared key" ) );
return( 0 );
@ -3648,9 +3688,7 @@ static int ssl_parse_client_psk_identity( mbedtls_ssl_context *ssl, unsigned cha
int ret = 0;
size_t n;
if( ssl->conf->f_psk == NULL &&
( ssl->conf->psk == NULL || ssl->conf->psk_identity == NULL ||
ssl->conf->psk_identity_len == 0 || ssl->conf->psk_len == 0 ) )
if( ssl_conf_has_psk_or_cb( ssl->conf ) == 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "got no pre-shared key" ) );
return( MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED );
@ -3828,6 +3866,13 @@ static int ssl_parse_client_key_exchange( mbedtls_ssl_context *ssl )
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE );
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* For opaque PSKs, we perform the PSK-to-MS derivation atomatically
* and skip the intermediate PMS. */
if( ssl_use_opaque_psk( ssl ) )
MBEDTLS_SSL_DEBUG_MSG( 1, ( "skip PMS generation for opaque PSK" ) );
else
#endif /* MBEDTLS_USE_PSA_CRYPTO */
if( ( ret = mbedtls_ssl_psk_derive_premaster( ssl,
ciphersuite_info->key_exchange ) ) != 0 )
{
@ -3859,6 +3904,12 @@ static int ssl_parse_client_key_exchange( mbedtls_ssl_context *ssl )
return( ret );
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* Opaque PSKs are currently only supported for PSK-only. */
if( ssl_use_opaque_psk( ssl ) == 1 )
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
#endif
if( ( ret = ssl_parse_encrypted_pms( ssl, p, end, 2 ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_encrypted_pms" ), ret );
@ -3888,6 +3939,12 @@ static int ssl_parse_client_key_exchange( mbedtls_ssl_context *ssl )
return( ret );
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* Opaque PSKs are currently only supported for PSK-only. */
if( ssl_use_opaque_psk( ssl ) == 1 )
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
#endif
if( p != end )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client key exchange" ) );
@ -3919,6 +3976,12 @@ static int ssl_parse_client_key_exchange( mbedtls_ssl_context *ssl )
return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_KEY_EXCHANGE_RP );
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* Opaque PSKs are currently only supported for PSK-only. */
if( ssl_use_opaque_psk( ssl ) == 1 )
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
#endif
MBEDTLS_SSL_DEBUG_ECP( 3, "ECDH: Qp ", &ssl->handshake->ecdh_ctx.Qp );
if( ( ret = mbedtls_ssl_psk_derive_premaster( ssl,