Merge pull request #618 from hanno-arm/record_checking_api-baremetal

[Baremetal] Record checking: API, Documentation and Stubs
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Manuel Pégourié-Gonnard 2019-07-30 17:11:46 +02:00 committed by GitHub
commit 6852e95c2a
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GPG key ID: 4AEE18F83AFDEB23
7 changed files with 367 additions and 30 deletions

View file

@ -1293,6 +1293,19 @@
*/
#define MBEDTLS_SSL_ALL_ALERT_MESSAGES
/**
* \def MBEDTLS_SSL_RECORD_CHECKING
*
* Enable the API mbedtls_ssl_check_record() which allows to check the
* validity, freshness and authenticity of an incoming record without
* modifying the externally visible state of the SSL context.
*
* See mbedtls_ssl_check_record() for more information.
*
* Uncomment to enable support for record checking.
*/
#define MBEDTLS_SSL_RECORD_CHECKING
/**
* \def MBEDTLS_SSL_DTLS_CONNECTION_ID
*

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@ -1898,6 +1898,54 @@ void mbedtls_ssl_set_mtu( mbedtls_ssl_context *ssl, uint16_t mtu );
void mbedtls_ssl_conf_read_timeout( mbedtls_ssl_config *conf, uint32_t timeout );
#endif /* !MBEDTLS_SSL_CONF_READ_TIMEOUT */
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
/**
* \brief Check whether a buffer contains a valid, fresh
* and authentic record (DTLS only).
*
* This function does not change the user-visible state
* of the SSL context. Its sole purpose is to provide
* an indication of the legitimacy of an incoming record.
*
* This can be useful e.g. in distributed server environments
* using the DTLS Connection ID feature, in which connections
* might need to be passed between service instances on a change
* of peer address, but where such disruptive operations should
* only happen after the validity of incoming records has been
* confirmed.
*
* \param ssl The SSL context to use.
* \param buf The address of the buffer holding the record to be checked.
* This must be an R/W buffer of length \p buflen Bytes.
* \param buflen The length of \p buf in Bytes.
*
* \note This routine only checks whether the provided buffer begins
* with a valid, fresh and authentic record, but does not check
* potential data following the initial record. In particular,
* it is possible to pass DTLS datagrams containing multiple
* records, in which case only the first record is checked.
*
* \note This function modifies the input buffer \p buf. If you need
* to preserve the original record, you have to maintain a copy.
*
* \return \c 0 if the record is valid, fresh and authentic.
* \return MBEDTLS_ERR_SSL_INVALID_MAC if the check completed
* successfully but the record was found to be not authentic.
* \return MBEDTLS_ERR_SSL_INVALID_RECORD if the check completed
* successfully but the record was found to be invalid for
* a reason different from authenticity checking.
* \return MBEDTLS_ERR_SSL_UNEXPECTED_RECORD if the check completed
* successfully but the record was found to be unexpected
* in the state of the SSL context, including replayed records.
* \return Another negative error code on different kinds of failure.
* In this case, the SSL context becomes unusable and needs
* to be freed or reset before reuse.
*/
int mbedtls_ssl_check_record( mbedtls_ssl_context const *ssl,
unsigned char *buf,
size_t buflen );
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
#if !defined(MBEDTLS_SSL_CONF_SET_TIMER) && \
!defined(MBEDTLS_SSL_CONF_GET_TIMER)
/**

View file

@ -122,6 +122,18 @@ static void ssl_update_out_pointers( mbedtls_ssl_context *ssl,
mbedtls_ssl_transform *transform );
static void ssl_update_in_pointers( mbedtls_ssl_context *ssl );
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
int mbedtls_ssl_check_record( mbedtls_ssl_context const *ssl,
unsigned char *buf,
size_t buflen )
{
((void) ssl);
((void) buf);
((void) buflen);
return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
}
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
#define SSL_DONT_FORCE_FLUSH 0
#define SSL_FORCE_FLUSH 1

View file

@ -438,6 +438,9 @@ static const char *features[] = {
#if defined(MBEDTLS_SSL_ALL_ALERT_MESSAGES)
"MBEDTLS_SSL_ALL_ALERT_MESSAGES",
#endif /* MBEDTLS_SSL_ALL_ALERT_MESSAGES */
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
"MBEDTLS_SSL_RECORD_CHECKING",
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
"MBEDTLS_SSL_DTLS_CONNECTION_ID",
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */

View file

@ -1210,6 +1210,14 @@ int query_config( const char *config )
}
#endif /* MBEDTLS_SSL_ALL_ALERT_MESSAGES */
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
if( strcmp( "MBEDTLS_SSL_RECORD_CHECKING", config ) == 0 )
{
MACRO_EXPANSION_TO_STR( MBEDTLS_SSL_RECORD_CHECKING );
return( 0 );
}
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
if( strcmp( "MBEDTLS_SSL_DTLS_CONNECTION_ID", config ) == 0 )
{

View file

@ -490,7 +490,8 @@ static void my_debug( void *ctx, int level,
* Test recv/send functions that make sure each try returns
* WANT_READ/WANT_WRITE at least once before sucesseding
*/
static int my_recv( void *ctx, unsigned char *buf, size_t len )
static int delayed_recv( void *ctx, unsigned char *buf, size_t len )
{
static int first_try = 1;
int ret;
@ -507,7 +508,7 @@ static int my_recv( void *ctx, unsigned char *buf, size_t len )
return( ret );
}
static int my_send( void *ctx, const unsigned char *buf, size_t len )
static int delayed_send( void *ctx, const unsigned char *buf, size_t len )
{
static int first_try = 1;
int ret;
@ -527,6 +528,137 @@ static int my_send( void *ctx, const unsigned char *buf, size_t len )
MBEDTLS_SSL_CONF_SEND &&
MBEDTLS_SSL_CONF_RECV_TIMEOUT */
typedef struct
{
mbedtls_ssl_context *ssl;
mbedtls_net_context *net;
} io_ctx_t;
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
static int ssl_check_record( mbedtls_ssl_context const *ssl,
unsigned char const *buf, size_t len )
{
int ret;
unsigned char *tmp_buf;
tmp_buf = mbedtls_calloc( 1, len );
if( tmp_buf == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
memcpy( tmp_buf, buf, len );
ret = mbedtls_ssl_check_record( ssl, tmp_buf, len );
if( ret != MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE )
{
int ret_repeated;
/* Test-only: Make sure that mbedtls_ssl_check_record()
* doesn't alter state. */
memcpy( tmp_buf, buf, len ); /* Restore buffer */
ret_repeated = mbedtls_ssl_check_record( ssl, tmp_buf, len );
if( ret != ret_repeated )
{
mbedtls_printf( "mbedtls_ssl_check_record() returned inconsistent results.\n" );
return( -1 );
}
switch( ret )
{
case 0:
break;
case MBEDTLS_ERR_SSL_INVALID_RECORD:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected invalid record.\n" );
break;
case MBEDTLS_ERR_SSL_INVALID_MAC:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected unauthentic record.\n" );
break;
case MBEDTLS_ERR_SSL_UNEXPECTED_RECORD:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected unexpected record.\n" );
break;
default:
mbedtls_printf( "mbedtls_ssl_check_record() failed fatally with -%#04x.\n", -ret );
return( -1 );
}
/* Regardless of the outcome, forward the record to the stack. */
}
mbedtls_free( tmp_buf );
return( 0 );
}
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
static int recv_cb( void *ctx, unsigned char *buf, size_t len )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
size_t recv_len;
int ret;
if( opt.nbio == 2 )
ret = delayed_recv( io_ctx->net, buf, len );
else
ret = mbedtls_net_recv( io_ctx->net, buf, len );
if( ret < 0 )
return( ret );
recv_len = (size_t) ret;
if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Here's the place to do any datagram/record checking
* in between receiving the packet from the underlying
* transport and passing it on to the TLS stack. */
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
if( ssl_check_record( io_ctx->ssl, buf, recv_len ) != 0 )
return( -1 );
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
}
return( (int) recv_len );
}
static int recv_timeout_cb( void *ctx, unsigned char *buf, size_t len,
uint32_t timeout )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
int ret;
size_t recv_len;
ret = mbedtls_net_recv_timeout( io_ctx->net, buf, len, timeout );
if( ret < 0 )
return( ret );
recv_len = (size_t) ret;
if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Here's the place to do any datagram/record checking
* in between receiving the packet from the underlying
* transport and passing it on to the TLS stack. */
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
if( ssl_check_record( io_ctx->ssl, buf, recv_len ) != 0 )
return( -1 );
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
}
return( (int) recv_len );
}
static int send_cb( void *ctx, unsigned char const *buf, size_t len )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
if( opt.nbio == 2 )
return( delayed_send( io_ctx->net, buf, len ) );
return( mbedtls_net_send( io_ctx->net, buf, len ) );
}
#if defined(MBEDTLS_X509_CRT_PARSE_C)
static unsigned char peer_crt_info[1024];
@ -761,6 +893,7 @@ int main( int argc, char *argv[] )
{
int ret = 0, len, tail_len, i, written, frags, retry_left;
mbedtls_net_context server_fd;
io_ctx_t io_ctx;
unsigned char buf[MAX_REQUEST_SIZE + 1];
@ -1928,12 +2061,10 @@ int main( int argc, char *argv[] )
#if !defined(MBEDTLS_SSL_CONF_RECV) && \
!defined(MBEDTLS_SSL_CONF_SEND) && \
!defined(MBEDTLS_SSL_CONF_RECV_TIMEOUT)
if( opt.nbio == 2 )
mbedtls_ssl_set_bio( &ssl, &server_fd, my_send, my_recv, NULL );
else
mbedtls_ssl_set_bio( &ssl, &server_fd,
mbedtls_net_send, mbedtls_net_recv,
opt.nbio == 0 ? mbedtls_net_recv_timeout : NULL );
io_ctx.ssl = &ssl;
io_ctx.net = &server_fd;
mbedtls_ssl_set_bio( &ssl, &io_ctx, send_cb, recv_cb,
opt.nbio == 0 ? recv_timeout_cb : NULL );
#else
mbedtls_ssl_set_bio_ctx( &ssl, &server_fd );
#endif
@ -2550,13 +2681,8 @@ send_request:
goto exit;
}
if( opt.nbio == 2 )
mbedtls_ssl_set_bio( &ssl, &server_fd, my_send, my_recv,
NULL );
else
mbedtls_ssl_set_bio( &ssl, &server_fd, mbedtls_net_send,
mbedtls_net_recv,
opt.nbio == 0 ? mbedtls_net_recv_timeout : NULL );
mbedtls_ssl_set_bio( &ssl, &io_ctx, send_cb, recv_cb,
opt.nbio == 0 ? recv_timeout_cb : NULL );
#if defined(MBEDTLS_TIMING_C)
#if !defined(MBEDTLS_SSL_CONF_SET_TIMER) && \

View file

@ -621,7 +621,7 @@ static void my_debug( void *ctx, int level,
* Test recv/send functions that make sure each try returns
* WANT_READ/WANT_WRITE at least once before sucesseding
*/
static int my_recv( void *ctx, unsigned char *buf, size_t len )
static int delayed_recv( void *ctx, unsigned char *buf, size_t len )
{
static int first_try = 1;
int ret;
@ -638,7 +638,7 @@ static int my_recv( void *ctx, unsigned char *buf, size_t len )
return( ret );
}
static int my_send( void *ctx, const unsigned char *buf, size_t len )
static int delayed_send( void *ctx, const unsigned char *buf, size_t len )
{
static int first_try = 1;
int ret;
@ -658,6 +658,139 @@ static int my_send( void *ctx, const unsigned char *buf, size_t len )
MBEDTLS_SSL_CONF_SEND &&
MBEDTLS_SSL_CONF_RECV_TIMEOUT */
typedef struct
{
mbedtls_ssl_context *ssl;
mbedtls_net_context *net;
} io_ctx_t;
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
static int ssl_check_record( mbedtls_ssl_context const *ssl,
unsigned char const *buf, size_t len )
{
int ret;
unsigned char *tmp_buf;
/* Record checking may modify the input buffer,
* so make a copy. */
tmp_buf = mbedtls_calloc( 1, len );
if( tmp_buf == NULL )
return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
memcpy( tmp_buf, buf, len );
ret = mbedtls_ssl_check_record( ssl, tmp_buf, len );
if( ret != MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE )
{
int ret_repeated;
/* Test-only: Make sure that mbedtls_ssl_check_record()
* doesn't alter state. */
memcpy( tmp_buf, buf, len ); /* Restore buffer */
ret_repeated = mbedtls_ssl_check_record( ssl, tmp_buf, len );
if( ret != ret_repeated )
{
mbedtls_printf( "mbedtls_ssl_check_record() returned inconsistent results.\n" );
return( -1 );
}
switch( ret )
{
case 0:
break;
case MBEDTLS_ERR_SSL_INVALID_RECORD:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected invalid record.\n" );
break;
case MBEDTLS_ERR_SSL_INVALID_MAC:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected unauthentic record.\n" );
break;
case MBEDTLS_ERR_SSL_UNEXPECTED_RECORD:
if( opt.debug_level > 1 )
mbedtls_printf( "mbedtls_ssl_check_record() detected unexpected record.\n" );
break;
default:
mbedtls_printf( "mbedtls_ssl_check_record() failed fatally with -%#04x.\n", -ret );
return( -1 );
}
/* Regardless of the outcome, forward the record to the stack. */
}
mbedtls_free( tmp_buf );
return( 0 );
}
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
static int recv_cb( void *ctx, unsigned char *buf, size_t len )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
size_t recv_len;
int ret;
if( opt.nbio == 2 )
ret = delayed_recv( io_ctx->net, buf, len );
else
ret = mbedtls_net_recv( io_ctx->net, buf, len );
if( ret < 0 )
return( ret );
recv_len = (size_t) ret;
if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Here's the place to do any datagram/record checking
* in between receiving the packet from the underlying
* transport and passing it on to the TLS stack. */
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
if( ssl_check_record( io_ctx->ssl, buf, recv_len ) != 0 )
return( -1 );
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
}
return( (int) recv_len );
}
static int recv_timeout_cb( void *ctx, unsigned char *buf, size_t len,
uint32_t timeout )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
int ret;
size_t recv_len;
ret = mbedtls_net_recv_timeout( io_ctx->net, buf, len, timeout );
if( ret < 0 )
return( ret );
recv_len = (size_t) ret;
if( opt.transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM )
{
/* Here's the place to do any datagram/record checking
* in between receiving the packet from the underlying
* transport and passing it on to the TLS stack. */
#if defined(MBEDTLS_SSL_RECORD_CHECKING)
if( ssl_check_record( io_ctx->ssl, buf, recv_len ) != 0 )
return( -1 );
#endif /* MBEDTLS_SSL_RECORD_CHECKING */
}
return( (int) recv_len );
}
static int send_cb( void *ctx, unsigned char const *buf, size_t len )
{
io_ctx_t *io_ctx = (io_ctx_t*) ctx;
if( opt.nbio == 2 )
return( delayed_send( io_ctx->net, buf, len ) );
return( mbedtls_net_send( io_ctx->net, buf, len ) );
}
#if !defined(MBEDTLS_SSL_CONF_AUTHMODE)
/*
* Return authmode from string, or -1 on error
@ -1376,6 +1509,7 @@ int main( int argc, char *argv[] )
{
int ret = 0, len, written, frags, exchanges_left;
int version_suites[4][2];
io_ctx_t io_ctx;
unsigned char* buf = 0;
#if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
unsigned char psk[MBEDTLS_PSK_MAX_LEN];
@ -2918,12 +3052,10 @@ int main( int argc, char *argv[] )
#if !defined(MBEDTLS_SSL_CONF_RECV) && \
!defined(MBEDTLS_SSL_CONF_SEND) && \
!defined(MBEDTLS_SSL_CONF_RECV_TIMEOUT)
if( opt.nbio == 2 )
mbedtls_ssl_set_bio( &ssl, &client_fd, my_send, my_recv, NULL );
else
mbedtls_ssl_set_bio( &ssl, &client_fd,
mbedtls_net_send, mbedtls_net_recv,
opt.nbio == 0 ? mbedtls_net_recv_timeout : NULL );
io_ctx.ssl = &ssl;
io_ctx.net = &client_fd;
mbedtls_ssl_set_bio( &ssl, &io_ctx, send_cb, recv_cb,
opt.nbio == 0 ? recv_timeout_cb : NULL );
#else
mbedtls_ssl_set_bio_ctx( &ssl, &client_fd );
#endif
@ -3586,13 +3718,8 @@ data_exchange:
* if you want to share your set up code between the case of
* establishing a new connection and this case.
*/
if( opt.nbio == 2 )
mbedtls_ssl_set_bio( &ssl, &client_fd, my_send, my_recv,
NULL );
else
mbedtls_ssl_set_bio( &ssl, &client_fd, mbedtls_net_send,
mbedtls_net_recv,
opt.nbio == 0 ? mbedtls_net_recv_timeout : NULL );
mbedtls_ssl_set_bio( &ssl, &io_ctx, send_cb, recv_cb,
opt.nbio == 0 ? recv_timeout_cb : NULL );
#if defined(MBEDTLS_TIMING_C)
#if !defined(MBEDTLS_SSL_CONF_SET_TIMER) && \