mbedtls/library/pk.c
Manuel Pégourié-Gonnard 920c063bad Implement can_do for opaque ECC keypairs
Unfortunately the can_do wrapper does not receive the key context as an
argument, so it cannot check psa_get_key_information(). Later we might want to
change our internal structures to fix this, but for now we'll just restrict
opaque PSA keys to be ECDSA keypairs, as this is the only thing we need for
now. It also simplifies testing a bit (no need to test each key type).
2018-11-22 09:59:34 +01:00

539 lines
15 KiB
C

/*
* Public Key abstraction layer
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_PK_C)
#include "mbedtls/pk.h"
#include "mbedtls/pk_internal.h"
#include "mbedtls/platform_util.h"
#if defined(MBEDTLS_RSA_C)
#include "mbedtls/rsa.h"
#endif
#if defined(MBEDTLS_ECP_C)
#include "mbedtls/ecp.h"
#endif
#if defined(MBEDTLS_ECDSA_C)
#include "mbedtls/ecdsa.h"
#endif
#include <limits.h>
#include <stdint.h>
/*
* Initialise a mbedtls_pk_context
*/
void mbedtls_pk_init( mbedtls_pk_context *ctx )
{
if( ctx == NULL )
return;
ctx->pk_info = NULL;
ctx->pk_ctx = NULL;
}
/*
* Free (the components of) a mbedtls_pk_context
*/
void mbedtls_pk_free( mbedtls_pk_context *ctx )
{
if( ctx == NULL || ctx->pk_info == NULL )
return;
ctx->pk_info->ctx_free_func( ctx->pk_ctx );
mbedtls_platform_zeroize( ctx, sizeof( mbedtls_pk_context ) );
}
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/*
* Initialize a restart context
*/
void mbedtls_pk_restart_init( mbedtls_pk_restart_ctx *ctx )
{
ctx->pk_info = NULL;
ctx->rs_ctx = NULL;
}
/*
* Free the components of a restart context
*/
void mbedtls_pk_restart_free( mbedtls_pk_restart_ctx *ctx )
{
if( ctx == NULL || ctx->pk_info == NULL ||
ctx->pk_info->rs_free_func == NULL )
{
return;
}
ctx->pk_info->rs_free_func( ctx->rs_ctx );
ctx->pk_info = NULL;
ctx->rs_ctx = NULL;
}
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
/*
* Get pk_info structure from type
*/
const mbedtls_pk_info_t * mbedtls_pk_info_from_type( mbedtls_pk_type_t pk_type )
{
switch( pk_type ) {
#if defined(MBEDTLS_RSA_C)
case MBEDTLS_PK_RSA:
return( &mbedtls_rsa_info );
#endif
#if defined(MBEDTLS_ECP_C)
case MBEDTLS_PK_ECKEY:
return( &mbedtls_eckey_info );
case MBEDTLS_PK_ECKEY_DH:
return( &mbedtls_eckeydh_info );
#endif
#if defined(MBEDTLS_ECDSA_C)
case MBEDTLS_PK_ECDSA:
return( &mbedtls_ecdsa_info );
#endif
/* MBEDTLS_PK_RSA_ALT omitted on purpose */
default:
return( NULL );
}
}
/*
* Initialise context
*/
int mbedtls_pk_setup( mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info )
{
if( ctx == NULL || info == NULL || ctx->pk_info != NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ( ctx->pk_ctx = info->ctx_alloc_func() ) == NULL )
return( MBEDTLS_ERR_PK_ALLOC_FAILED );
ctx->pk_info = info;
return( 0 );
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/*
* Initialise a PSA-wrapping context
*/
int mbedtls_pk_setup_psa( mbedtls_pk_context *ctx, const psa_key_slot_t key )
{
const mbedtls_pk_info_t * const info = &mbedtls_pk_opaque_psa_info;
psa_key_slot_t *pk_ctx;
psa_key_type_t type;
if( ctx == NULL || ctx->pk_info != NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( PSA_SUCCESS != psa_get_key_information( key, &type, NULL ) )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
/* Current implementation of can_do() relies on this. */
if( ! PSA_KEY_TYPE_IS_ECC_KEYPAIR( type ) )
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE) ;
if( ( ctx->pk_ctx = info->ctx_alloc_func() ) == NULL )
return( MBEDTLS_ERR_PK_ALLOC_FAILED );
ctx->pk_info = info;
pk_ctx = (psa_key_slot_t *) ctx->pk_ctx;
*pk_ctx = key;
return( 0 );
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#if defined(MBEDTLS_PK_RSA_ALT_SUPPORT)
/*
* Initialize an RSA-alt context
*/
int mbedtls_pk_setup_rsa_alt( mbedtls_pk_context *ctx, void * key,
mbedtls_pk_rsa_alt_decrypt_func decrypt_func,
mbedtls_pk_rsa_alt_sign_func sign_func,
mbedtls_pk_rsa_alt_key_len_func key_len_func )
{
mbedtls_rsa_alt_context *rsa_alt;
const mbedtls_pk_info_t *info = &mbedtls_rsa_alt_info;
if( ctx == NULL || ctx->pk_info != NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ( ctx->pk_ctx = info->ctx_alloc_func() ) == NULL )
return( MBEDTLS_ERR_PK_ALLOC_FAILED );
ctx->pk_info = info;
rsa_alt = (mbedtls_rsa_alt_context *) ctx->pk_ctx;
rsa_alt->key = key;
rsa_alt->decrypt_func = decrypt_func;
rsa_alt->sign_func = sign_func;
rsa_alt->key_len_func = key_len_func;
return( 0 );
}
#endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */
/*
* Tell if a PK can do the operations of the given type
*/
int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type )
{
/* null or NONE context can't do anything */
if( ctx == NULL || ctx->pk_info == NULL )
return( 0 );
return( ctx->pk_info->can_do( type ) );
}
/*
* Helper for mbedtls_pk_sign and mbedtls_pk_verify
*/
static inline int pk_hashlen_helper( mbedtls_md_type_t md_alg, size_t *hash_len )
{
const mbedtls_md_info_t *md_info;
if( *hash_len != 0 )
return( 0 );
if( ( md_info = mbedtls_md_info_from_type( md_alg ) ) == NULL )
return( -1 );
*hash_len = mbedtls_md_get_size( md_info );
return( 0 );
}
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/*
* Helper to set up a restart context if needed
*/
static int pk_restart_setup( mbedtls_pk_restart_ctx *ctx,
const mbedtls_pk_info_t *info )
{
/* Don't do anything if already set up or invalid */
if( ctx == NULL || ctx->pk_info != NULL )
return( 0 );
/* Should never happen when we're called */
if( info->rs_alloc_func == NULL || info->rs_free_func == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ( ctx->rs_ctx = info->rs_alloc_func() ) == NULL )
return( MBEDTLS_ERR_PK_ALLOC_FAILED );
ctx->pk_info = info;
return( 0 );
}
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
/*
* Verify a signature (restartable)
*/
int mbedtls_pk_verify_restartable( mbedtls_pk_context *ctx,
mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
const unsigned char *sig, size_t sig_len,
mbedtls_pk_restart_ctx *rs_ctx )
{
if( ctx == NULL || ctx->pk_info == NULL ||
pk_hashlen_helper( md_alg, &hash_len ) != 0 )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/* optimization: use non-restartable version if restart disabled */
if( rs_ctx != NULL &&
mbedtls_ecp_restart_is_enabled() &&
ctx->pk_info->verify_rs_func != NULL )
{
int ret;
if( ( ret = pk_restart_setup( rs_ctx, ctx->pk_info ) ) != 0 )
return( ret );
ret = ctx->pk_info->verify_rs_func( ctx->pk_ctx,
md_alg, hash, hash_len, sig, sig_len, rs_ctx->rs_ctx );
if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
mbedtls_pk_restart_free( rs_ctx );
return( ret );
}
#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
(void) rs_ctx;
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
if( ctx->pk_info->verify_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
return( ctx->pk_info->verify_func( ctx->pk_ctx, md_alg, hash, hash_len,
sig, sig_len ) );
}
/*
* Verify a signature
*/
int mbedtls_pk_verify( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
const unsigned char *sig, size_t sig_len )
{
return( mbedtls_pk_verify_restartable( ctx, md_alg, hash, hash_len,
sig, sig_len, NULL ) );
}
/*
* Verify a signature with options
*/
int mbedtls_pk_verify_ext( mbedtls_pk_type_t type, const void *options,
mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
const unsigned char *sig, size_t sig_len )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ! mbedtls_pk_can_do( ctx, type ) )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
if( type == MBEDTLS_PK_RSASSA_PSS )
{
#if defined(MBEDTLS_RSA_C) && defined(MBEDTLS_PKCS1_V21)
int ret;
const mbedtls_pk_rsassa_pss_options *pss_opts;
#if SIZE_MAX > UINT_MAX
if( md_alg == MBEDTLS_MD_NONE && UINT_MAX < hash_len )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
#endif /* SIZE_MAX > UINT_MAX */
if( options == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
pss_opts = (const mbedtls_pk_rsassa_pss_options *) options;
if( sig_len < mbedtls_pk_get_len( ctx ) )
return( MBEDTLS_ERR_RSA_VERIFY_FAILED );
ret = mbedtls_rsa_rsassa_pss_verify_ext( mbedtls_pk_rsa( *ctx ),
NULL, NULL, MBEDTLS_RSA_PUBLIC,
md_alg, (unsigned int) hash_len, hash,
pss_opts->mgf1_hash_id,
pss_opts->expected_salt_len,
sig );
if( ret != 0 )
return( ret );
if( sig_len > mbedtls_pk_get_len( ctx ) )
return( MBEDTLS_ERR_PK_SIG_LEN_MISMATCH );
return( 0 );
#else
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE );
#endif /* MBEDTLS_RSA_C && MBEDTLS_PKCS1_V21 */
}
/* General case: no options */
if( options != NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
return( mbedtls_pk_verify( ctx, md_alg, hash, hash_len, sig, sig_len ) );
}
/*
* Make a signature (restartable)
*/
int mbedtls_pk_sign_restartable( mbedtls_pk_context *ctx,
mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
unsigned char *sig, size_t *sig_len,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
mbedtls_pk_restart_ctx *rs_ctx )
{
if( ctx == NULL || ctx->pk_info == NULL ||
pk_hashlen_helper( md_alg, &hash_len ) != 0 )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/* optimization: use non-restartable version if restart disabled */
if( rs_ctx != NULL &&
mbedtls_ecp_restart_is_enabled() &&
ctx->pk_info->sign_rs_func != NULL )
{
int ret;
if( ( ret = pk_restart_setup( rs_ctx, ctx->pk_info ) ) != 0 )
return( ret );
ret = ctx->pk_info->sign_rs_func( ctx->pk_ctx, md_alg,
hash, hash_len, sig, sig_len, f_rng, p_rng, rs_ctx->rs_ctx );
if( ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
mbedtls_pk_restart_free( rs_ctx );
return( ret );
}
#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
(void) rs_ctx;
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
if( ctx->pk_info->sign_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
return( ctx->pk_info->sign_func( ctx->pk_ctx, md_alg, hash, hash_len,
sig, sig_len, f_rng, p_rng ) );
}
/*
* Make a signature
*/
int mbedtls_pk_sign( mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hash_len,
unsigned char *sig, size_t *sig_len,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
{
return( mbedtls_pk_sign_restartable( ctx, md_alg, hash, hash_len,
sig, sig_len, f_rng, p_rng, NULL ) );
}
/*
* Decrypt message
*/
int mbedtls_pk_decrypt( mbedtls_pk_context *ctx,
const unsigned char *input, size_t ilen,
unsigned char *output, size_t *olen, size_t osize,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ctx->pk_info->decrypt_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
return( ctx->pk_info->decrypt_func( ctx->pk_ctx, input, ilen,
output, olen, osize, f_rng, p_rng ) );
}
/*
* Encrypt message
*/
int mbedtls_pk_encrypt( mbedtls_pk_context *ctx,
const unsigned char *input, size_t ilen,
unsigned char *output, size_t *olen, size_t osize,
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ctx->pk_info->encrypt_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
return( ctx->pk_info->encrypt_func( ctx->pk_ctx, input, ilen,
output, olen, osize, f_rng, p_rng ) );
}
/*
* Check public-private key pair
*/
int mbedtls_pk_check_pair( const mbedtls_pk_context *pub, const mbedtls_pk_context *prv )
{
if( pub == NULL || pub->pk_info == NULL ||
prv == NULL || prv->pk_info == NULL )
{
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
}
if( prv->pk_info->check_pair_func == NULL )
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE );
if( prv->pk_info->type == MBEDTLS_PK_RSA_ALT )
{
if( pub->pk_info->type != MBEDTLS_PK_RSA )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
}
else
{
if( pub->pk_info != prv->pk_info )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
}
return( prv->pk_info->check_pair_func( pub->pk_ctx, prv->pk_ctx ) );
}
/*
* Get key size in bits
*/
size_t mbedtls_pk_get_bitlen( const mbedtls_pk_context *ctx )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( 0 );
return( ctx->pk_info->get_bitlen( ctx->pk_ctx ) );
}
/*
* Export debug information
*/
int mbedtls_pk_debug( const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( MBEDTLS_ERR_PK_BAD_INPUT_DATA );
if( ctx->pk_info->debug_func == NULL )
return( MBEDTLS_ERR_PK_TYPE_MISMATCH );
ctx->pk_info->debug_func( ctx->pk_ctx, items );
return( 0 );
}
/*
* Access the PK type name
*/
const char *mbedtls_pk_get_name( const mbedtls_pk_context *ctx )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( "invalid PK" );
return( ctx->pk_info->name );
}
/*
* Access the PK type
*/
mbedtls_pk_type_t mbedtls_pk_get_type( const mbedtls_pk_context *ctx )
{
if( ctx == NULL || ctx->pk_info == NULL )
return( MBEDTLS_PK_NONE );
return( ctx->pk_info->type );
}
#endif /* MBEDTLS_PK_C */