Add NULL check in prepare hello

`session_negotiate` is used directly in `ssl_prepare_client_hello`
without NULL check. Add the check in the beggining to avoid segment
fault.

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
This commit is contained in:
Jerry Yu 2022-10-11 15:58:51 +08:00
parent c2bfaf00d9
commit 22c18c1432

View File

@ -713,26 +713,29 @@ static int ssl_generate_random( mbedtls_ssl_context *ssl )
MBEDTLS_CLIENT_HELLO_RANDOM_LEN - gmt_unix_time_len ); MBEDTLS_CLIENT_HELLO_RANDOM_LEN - gmt_unix_time_len );
return( ret ); return( ret );
} }
MBEDTLS_CHECK_RETURN_CRITICAL MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_prepare_client_hello( mbedtls_ssl_context *ssl ) static int ssl_prepare_client_hello( mbedtls_ssl_context *ssl )
{ {
int ret; int ret;
size_t session_id_len; size_t session_id_len;
mbedtls_ssl_session *session_negotiate = ssl->session_negotiate;
if( session_negotiate == NULL )
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
#if defined(MBEDTLS_SSL_PROTO_TLS1_3) && \ #if defined(MBEDTLS_SSL_PROTO_TLS1_3) && \
defined(MBEDTLS_SSL_SESSION_TICKETS) && \ defined(MBEDTLS_SSL_SESSION_TICKETS) && \
defined(MBEDTLS_HAVE_TIME) defined(MBEDTLS_HAVE_TIME)
/* Check if a tls13 ticket has been configured. */ /* Check if a tls13 ticket has been configured. */
if( ssl->session_negotiate->tls_version == MBEDTLS_SSL_VERSION_TLS1_3 && if( ssl->handshake->resume != 0 &&
ssl->handshake->resume != 0 && session_negotiate->tls_version == MBEDTLS_SSL_VERSION_TLS1_3 &&
ssl->session_negotiate != NULL && session_negotiate->ticket != NULL )
ssl->session_negotiate->ticket != NULL )
{ {
mbedtls_time_t now = mbedtls_time( NULL ); mbedtls_time_t now = mbedtls_time( NULL );
if( ssl->session_negotiate->ticket_received > now || uint64_t age = (uint64_t)( now - session_negotiate->ticket_received );
(uint64_t)( now - ssl->session_negotiate->ticket_received ) if( session_negotiate->ticket_received > now ||
> ssl->session_negotiate->ticket_lifetime ) age > session_negotiate->ticket_lifetime )
{ {
/* Without valid ticket, disable session resumption.*/ /* Without valid ticket, disable session resumption.*/
MBEDTLS_SSL_DEBUG_MSG( MBEDTLS_SSL_DEBUG_MSG(
@ -761,7 +764,7 @@ static int ssl_prepare_client_hello( mbedtls_ssl_context *ssl )
{ {
if( ssl->handshake->resume ) if( ssl->handshake->resume )
{ {
ssl->tls_version = ssl->session_negotiate->tls_version; ssl->tls_version = session_negotiate->tls_version;
ssl->handshake->min_tls_version = ssl->tls_version; ssl->handshake->min_tls_version = ssl->tls_version;
} }
else else
@ -795,7 +798,7 @@ static int ssl_prepare_client_hello( mbedtls_ssl_context *ssl )
* to zero, except in the case of a TLS 1.2 session renegotiation or * to zero, except in the case of a TLS 1.2 session renegotiation or
* session resumption. * session resumption.
*/ */
session_id_len = ssl->session_negotiate->id_len; session_id_len = session_negotiate->id_len;
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) #if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if( ssl->tls_version == MBEDTLS_SSL_VERSION_TLS1_2 ) if( ssl->tls_version == MBEDTLS_SSL_VERSION_TLS1_2 )
@ -818,8 +821,8 @@ static int ssl_prepare_client_hello( mbedtls_ssl_context *ssl )
if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE ) if( ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE )
#endif #endif
{ {
if( ( ssl->session_negotiate->ticket != NULL ) && if( ( session_negotiate->ticket != NULL ) &&
( ssl->session_negotiate->ticket_len != 0 ) ) ( session_negotiate->ticket_len != 0 ) )
{ {
session_id_len = 32; session_id_len = 32;
} }
@ -851,13 +854,13 @@ static int ssl_prepare_client_hello( mbedtls_ssl_context *ssl )
} }
#endif /* MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE */ #endif /* MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE */
if( session_id_len != ssl->session_negotiate->id_len ) if( session_id_len != session_negotiate->id_len )
{ {
ssl->session_negotiate->id_len = session_id_len; session_negotiate->id_len = session_id_len;
if( session_id_len > 0 ) if( session_id_len > 0 )
{ {
ret = ssl->conf->f_rng( ssl->conf->p_rng, ret = ssl->conf->f_rng( ssl->conf->p_rng,
ssl->session_negotiate->id, session_negotiate->id,
session_id_len ); session_id_len );
if( ret != 0 ) if( ret != 0 )
{ {
@ -869,7 +872,6 @@ static int ssl_prepare_client_hello( mbedtls_ssl_context *ssl )
return( 0 ); return( 0 );
} }
/* /*
* Write ClientHello handshake message. * Write ClientHello handshake message.
* Handler for MBEDTLS_SSL_CLIENT_HELLO * Handler for MBEDTLS_SSL_CLIENT_HELLO