Add thread safety to ECP hardware acceleration

The intended use of the abstraction layer for Elliptic Curve Point
arithmetic is to enable using hardware cryptographic accelerators.
These devices are a shared resource and the driver code rarely provides
thread safety.

This commit adds mutexes to the abstraction layer to protect the device
in a multi-threaded environment.
This commit is contained in:
Janos Follath 2016-11-03 14:25:37 +00:00 committed by Andres AG
parent 46315740b8
commit b9dbff7260

View File

@ -49,6 +49,7 @@
#if defined(MBEDTLS_ECP_C)
#include "mbedtls/ecp.h"
#include "mbedtls/threading.h"
#include <string.h>
@ -1685,34 +1686,44 @@ int mbedtls_ecp_mul( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
( ret = mbedtls_ecp_check_pubkey( grp, P ) ) != 0 )
return( ret );
#if defined(MBEDTLS_ECP_FUNCTION_ALT) && defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_lock( &mbedtls_threading_cryptohw_asym_mutex ) != 0 )
return ( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
#if defined(MBEDTLS_ECP_INIT_ALT)
if ( mbedtls_ecp_alt_grp_capable( grp ) )
{
MBEDTLS_MPI_CHK( mbedtls_ecp_alt_init( grp ) );
}
#endif
#endif
#if defined(ECP_MONTGOMERY)
if( ecp_get_type( grp ) == ECP_TYPE_MONTGOMERY )
ret = ecp_mul_mxz( grp, R, m, P, f_rng, p_rng );
#endif
#endif
#if defined(ECP_SHORTWEIERSTRASS)
if( ecp_get_type( grp ) == ECP_TYPE_SHORT_WEIERSTRASS )
ret = ecp_mul_comb( grp, R, m, P, f_rng, p_rng );
#endif
#endif
#if defined(MBEDTLS_ECP_INIT_ALT)
cleanup:
#endif
#endif
#if defined(MBEDTLS_ECP_DEINIT_ALT)
if ( mbedtls_ecp_alt_grp_capable( grp ) )
{
mbedtls_ecp_alt_deinit( grp );
}
#endif
#endif
#if defined(MBEDTLS_ECP_FUNCTION_ALT) && defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &mbedtls_threading_cryptohw_asym_mutex ) != 0 )
return ( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
return( ret );
}
@ -1815,11 +1826,17 @@ int mbedtls_ecp_muladd( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
MBEDTLS_MPI_CHK( mbedtls_ecp_mul_shortcuts( grp, &mP, m, P ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_mul_shortcuts( grp, R, n, Q ) );
#if defined(MBEDTLS_ECP_FUNCTION_ALT) && defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_lock( &mbedtls_threading_cryptohw_asym_mutex ) != 0 )
return ( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
#if defined(MBEDTLS_ECP_INIT_ALT)
if ( mbedtls_ecp_alt_grp_capable( grp ) )
{
MBEDTLS_MPI_CHK( mbedtls_ecp_alt_init( grp ) );
}
#endif
MBEDTLS_MPI_CHK( ecp_add_mixed( grp, R, &mP, R ) );
MBEDTLS_MPI_CHK( ecp_normalize_jac( grp, R ) );
@ -1831,8 +1848,13 @@ cleanup:
{
mbedtls_ecp_alt_deinit( grp );
}
#endif
#endif
#if defined(MBEDTLS_ECP_FUNCTION_ALT) && defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &mbedtls_threading_cryptohw_asym_mutex ) != 0 )
return ( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
mbedtls_ecp_point_free( &mP );
return( ret );