Make use of PSA crypto hash if MBEDTLS_MD_C isn't defined

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
This commit is contained in:
Neil Armstrong 2022-08-11 10:47:08 +02:00
parent 0d76341eac
commit ecaba1c9b2
3 changed files with 43 additions and 5 deletions

View File

@ -108,7 +108,8 @@
#endif
#if defined(MBEDTLS_ECJPAKE_C) && \
( !defined(MBEDTLS_ECP_C) || !defined(MBEDTLS_MD_C) )
( !defined(MBEDTLS_ECP_C) || \
!( defined(MBEDTLS_MD_C) || defined(MBEDTLS_PSA_CRYPTO_C) ) )
#error "MBEDTLS_ECJPAKE_C defined, but not all prerequisites"
#endif

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@ -2330,6 +2330,9 @@
* ECJPAKE
*
* Requires: MBEDTLS_ECP_C, MBEDTLS_MD_C
*
* \warning If building without MBEDTLS_MD_C, you must call psa_crypto_init()
* before doing any EC J-PAKE operations.
*/
#define MBEDTLS_ECJPAKE_C

View File

@ -30,6 +30,13 @@
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"
/* We use MD first if it's available (for compatibility reasons)
* and "fall back" to PSA otherwise (which needs psa_crypto_init()). */
#if !defined(MBEDTLS_MD_C)
#include "psa/crypto.h"
#include "mbedtls/psa_util.h"
#endif /* !MBEDTLS_MD_C */
#include "hash_info.h"
#include <string.h>
@ -47,6 +54,28 @@ static const char * const ecjpake_id[] = {
#define ID_MINE ( ecjpake_id[ ctx->role ] )
#define ID_PEER ( ecjpake_id[ 1 - ctx->role ] )
/**
* Helper to Compute a hash from md_type
*/
static int mbedtls_ecjpake_compute_hash( mbedtls_md_type_t md_type,
const unsigned char *input, size_t ilen,
unsigned char *output )
{
#if defined(MBEDTLS_MD_C)
return( mbedtls_md( mbedtls_md_info_from_type( md_type ),
input, ilen, output ) );
#else
psa_algorithm_t alg = mbedtls_psa_translate_md( md_type );
psa_status_t status;
size_t out_size = PSA_HASH_LENGTH( alg );
size_t out_len;
status = psa_hash_compute( alg, input, ilen, output, out_size, &out_len );
return( mbedtls_md_error_from_psa( status ) );
#endif /* !MBEDTLS_MD_C */
}
/*
* Initialize context
*/
@ -106,8 +135,13 @@ int mbedtls_ecjpake_setup( mbedtls_ecjpake_context *ctx,
ctx->role = role;
#if defined(MBEDTLS_MD_C)
if( ( mbedtls_md_info_from_type( hash ) ) == NULL )
return( MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE );
#else
if( mbedtls_psa_translate_md( hash ) == MBEDTLS_MD_NONE )
return( MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE );
#endif
ctx->md_type = hash;
@ -222,8 +256,8 @@ static int ecjpake_hash( const mbedtls_md_type_t md_type,
p += id_len;
/* Compute hash */
MBEDTLS_MPI_CHK( mbedtls_md( mbedtls_md_info_from_type( md_type ),
buf, p - buf, hash ) );
MBEDTLS_MPI_CHK( mbedtls_ecjpake_compute_hash( md_type,
buf, p - buf, hash ) );
/* Turn it into an integer mod n */
MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( h, hash,
@ -763,8 +797,8 @@ int mbedtls_ecjpake_derive_secret( mbedtls_ecjpake_context *ctx,
/* PMS = SHA-256( K.X ) */
x_bytes = ( ctx->grp.pbits + 7 ) / 8;
MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &K.X, kx, x_bytes ) );
MBEDTLS_MPI_CHK( mbedtls_md( mbedtls_md_info_from_type( ctx->md_type ),
kx, x_bytes, buf ) );
MBEDTLS_MPI_CHK( mbedtls_ecjpake_compute_hash( ctx->md_type,
kx, x_bytes, buf ) );
cleanup:
mbedtls_ecp_point_free( &K );