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mbedtls/library/x509_crt.c
Piotr Nowicki e048b91d25 Add returning a FAULT_DETECTED error on suspected FI attacks 
The change applies to the places where we prevent double synchronous
FI attacks with random delay, and where we do not respond to their
detection. The response to such an attack should be to return the
appropriate error code.

Signed-off-by: Piotr Nowicki <piotr.nowicki@arm.com>
2020-06-09 12:00:42 +02:00

4109 lines
125 KiB
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/*
* X.509 certificate parsing and verification
*
* 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)
*/
/*
* The ITU-T X.509 standard defines a certificate format for PKI.
*
* http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
* http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
* http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
*
* http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
* http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
*
* [SIRO] https://cabforum.org/wp-content/uploads/Chunghwatelecom201503cabforumV4.pdf
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_X509_CRT_PARSE_C)
#include "mbedtls/x509_crt.h"
#include "mbedtls/x509_internal.h"
#include "mbedtls/oid.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/platform.h"
#include <string.h>
#if defined(MBEDTLS_PEM_PARSE_C)
#include "mbedtls/pem.h"
#endif
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#include <stdlib.h>
#define mbedtls_free free
#define mbedtls_calloc calloc
#define mbedtls_snprintf snprintf
#endif
#if defined(MBEDTLS_THREADING_C)
#include "mbedtls/threading.h"
#endif
#if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
#include <windows.h>
#else
#include <time.h>
#endif
#if defined(MBEDTLS_FS_IO)
#include <stdio.h>
#if !defined(_WIN32) || defined(EFIX64) || defined(EFI32)
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#endif /* !_WIN32 || EFIX64 || EFI32 */
#endif
#if !defined(MBEDTLS_X509_ON_DEMAND_PARSING)
static void x509_buf_to_buf_raw( mbedtls_x509_buf_raw *dst,
mbedtls_x509_buf const *src )
{
dst->p = src->p;
dst->len = src->len;
}
static void x509_buf_raw_to_buf( mbedtls_x509_buf *dst,
mbedtls_x509_buf_raw const *src )
{
dst->p = src->p;
dst->len = src->len;
}
#endif /* MBEDTLS_X509_ON_DEMAND_PARSING */
static int x509_crt_parse_frame( unsigned char *start,
unsigned char *end,
mbedtls_x509_crt_frame *frame );
static int x509_crt_subject_from_frame( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_name *subject );
static int x509_crt_issuer_from_frame( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_name *issuer );
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
static int x509_crt_subject_alt_from_frame( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_sequence *subject_alt );
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
static int x509_crt_ext_key_usage_from_frame( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_sequence *ext_key_usage );
static int mbedtls_x509_crt_flush_cache_pk( mbedtls_x509_crt const *crt )
{
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_lock( &crt->cache->pk_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
/* Can only free the PK context if nobody is using it.
* If MBEDTLS_X509_ALWAYS_FLUSH is set, nested uses
* of xxx_acquire() are prohibited, and no reference
* counting is needed. Also, notice that the code-path
* below is safe if the cache isn't filled. */
if( crt->cache->pk_readers == 0 )
#endif /* !MBEDTLS_X509_ALWAYS_FLUSH ||
MBEDTLS_THREADING_C */
{
#if !defined(MBEDTLS_X509_ON_DEMAND_PARSING)
/* The cache holds a shallow copy of the PK context
* in the legacy struct, so don't free PK context. */
mbedtls_free( crt->cache->pk );
#else
mbedtls_pk_free( crt->cache->pk );
mbedtls_free( crt->cache->pk );
#endif /* MBEDTLS_X509_ON_DEMAND_PARSING */
crt->cache->pk = NULL;
}
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &crt->cache->pk_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
return( 0 );
}
static int mbedtls_x509_crt_flush_cache_frame( mbedtls_x509_crt const *crt )
{
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_lock( &crt->cache->frame_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
/* Can only free the PK context if nobody is using it.
* If MBEDTLS_X509_ALWAYS_FLUSH is set, nested uses
* of xxx_acquire() are prohibited, and no reference
* counting is needed. Also, notice that the code-path
* below is safe if the cache isn't filled. */
if( crt->cache->frame_readers == 0 )
#endif /* !MBEDTLS_X509_ALWAYS_FLUSH ||
MBEDTLS_THREADING_C */
{
mbedtls_free( crt->cache->frame );
crt->cache->frame = NULL;
}
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &crt->cache->frame_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif
return( 0 );
}
int mbedtls_x509_crt_flush_cache( mbedtls_x509_crt const *crt )
{
int ret;
ret = mbedtls_x509_crt_flush_cache_frame( crt );
if( ret != 0 )
return( ret );
ret = mbedtls_x509_crt_flush_cache_pk( crt );
if( ret != 0 )
return( ret );
return( 0 );
}
static int x509_crt_frame_parse_ext( mbedtls_x509_crt_frame *frame );
static int mbedtls_x509_crt_cache_provide_frame( mbedtls_x509_crt const *crt )
{
mbedtls_x509_crt_cache *cache = crt->cache;
mbedtls_x509_crt_frame *frame;
if( cache->frame != NULL )
{
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
return( 0 );
#else
/* If MBEDTLS_X509_ALWAYS_FLUSH is set, we don't
* allow nested uses of acquire. */
return( MBEDTLS_ERR_X509_FATAL_ERROR );
#endif
}
frame = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt_frame ) );
if( frame == NULL )
return( MBEDTLS_ERR_X509_ALLOC_FAILED );
cache->frame = frame;
#if defined(MBEDTLS_X509_ON_DEMAND_PARSING)
/* This would work with !MBEDTLS_X509_ON_DEMAND_PARSING, too,
* but is inefficient compared to copying the respective fields
* from the legacy mbedtls_x509_crt. */
return( x509_crt_parse_frame( crt->raw.p,
crt->raw.p + crt->raw.len,
frame ) );
#else /* MBEDTLS_X509_ON_DEMAND_PARSING */
/* Make sure all extension related fields are properly initialized. */
frame->ca_istrue = 0;
frame->max_pathlen = 0;
frame->ext_types = 0;
frame->version = crt->version;
frame->sig_md = crt->sig_md;
frame->sig_pk = crt->sig_pk;
#if !defined(MBEDTLS_X509_CRT_REMOVE_TIME)
frame->valid_from = crt->valid_from;
frame->valid_to = crt->valid_to;
#endif /* !MBEDTLS_X509_CRT_REMOVE_TIME */
x509_buf_to_buf_raw( &frame->raw, &crt->raw );
x509_buf_to_buf_raw( &frame->tbs, &crt->tbs );
x509_buf_to_buf_raw( &frame->serial, &crt->serial );
x509_buf_to_buf_raw( &frame->pubkey_raw, &crt->pk_raw );
x509_buf_to_buf_raw( &frame->issuer_raw, &crt->issuer_raw );
x509_buf_to_buf_raw( &frame->subject_raw, &crt->subject_raw );
#if !defined(MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID)
x509_buf_to_buf_raw( &frame->subject_id, &crt->subject_id );
x509_buf_to_buf_raw( &frame->issuer_id, &crt->issuer_id );
#endif /* !MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID */
x509_buf_to_buf_raw( &frame->sig, &crt->sig );
x509_buf_to_buf_raw( &frame->v3_ext, &crt->v3_ext );
/* The legacy CRT structure doesn't explicitly contain
* the `AlgorithmIdentifier` bounds; however, those can
* be inferred from the surrounding (mandatory) `SerialNumber`
* and `Issuer` fields. */
frame->sig_alg.p = crt->serial.p + crt->serial.len;
frame->sig_alg.len = crt->issuer_raw.p - frame->sig_alg.p;
return( x509_crt_frame_parse_ext( frame ) );
#endif /* !MBEDTLS_X509_ON_DEMAND_PARSING */
}
static int mbedtls_x509_crt_cache_provide_pk( mbedtls_x509_crt const *crt )
{
mbedtls_x509_crt_cache *cache = crt->cache;
mbedtls_pk_context *pk;
if( cache->pk != NULL )
{
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
return( 0 );
#else
/* If MBEDTLS_X509_ALWAYS_FLUSH is set, we don't
* allow nested uses of acquire. */
return( MBEDTLS_ERR_X509_FATAL_ERROR );
#endif
}
pk = mbedtls_calloc( 1, sizeof( mbedtls_pk_context ) );
if( pk == NULL )
return( MBEDTLS_ERR_X509_ALLOC_FAILED );
cache->pk = pk;
#if !defined(MBEDTLS_X509_ON_DEMAND_PARSING)
*pk = crt->pk;
return( 0 );
#else
{
mbedtls_x509_buf_raw pk_raw = cache->pk_raw;
return( mbedtls_pk_parse_subpubkey( &pk_raw.p,
pk_raw.p + pk_raw.len,
pk ) );
}
#endif /* MBEDTLS_X509_ON_DEMAND_PARSING */
}
static void x509_crt_cache_init( mbedtls_x509_crt_cache *cache )
{
memset( cache, 0, sizeof( *cache ) );
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_init( &cache->frame_mutex );
mbedtls_mutex_init( &cache->pk_mutex );
#endif
}
static void x509_crt_cache_clear_pk( mbedtls_x509_crt_cache *cache )
{
#if !defined(MBEDTLS_X509_ON_DEMAND_PARSING)
/* The cache holds a shallow copy of the PK context
* in the legacy struct, so don't free PK context. */
mbedtls_free( cache->pk );
#else
mbedtls_pk_free( cache->pk );
mbedtls_free( cache->pk );
#endif /* MBEDTLS_X509_ON_DEMAND_PARSING */
cache->pk = NULL;
}
static void x509_crt_cache_clear_frame( mbedtls_x509_crt_cache *cache )
{
mbedtls_free( cache->frame );
cache->frame = NULL;
}
static void x509_crt_cache_free( mbedtls_x509_crt_cache *cache )
{
if( cache == NULL )
return;
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_free( &cache->frame_mutex );
mbedtls_mutex_free( &cache->pk_mutex );
#endif
x509_crt_cache_clear_frame( cache );
x509_crt_cache_clear_pk( cache );
mbedtls_platform_memset( cache, 0, sizeof( *cache ) );
}
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
int mbedtls_x509_crt_get_subject_alt_names( mbedtls_x509_crt const *crt,
mbedtls_x509_sequence **subj_alt )
{
int ret;
mbedtls_x509_crt_frame const *frame;
mbedtls_x509_sequence *seq;
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( ret );
seq = mbedtls_calloc( 1, sizeof( mbedtls_x509_sequence ) );
if( seq == NULL )
ret = MBEDTLS_ERR_X509_ALLOC_FAILED;
else
ret = x509_crt_subject_alt_from_frame( frame, seq );
mbedtls_x509_crt_frame_release( crt );
*subj_alt = seq;
return( ret );
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
int mbedtls_x509_crt_get_ext_key_usage( mbedtls_x509_crt const *crt,
mbedtls_x509_sequence **ext_key_usage )
{
int ret;
mbedtls_x509_crt_frame const *frame;
mbedtls_x509_sequence *seq;
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( ret );
seq = mbedtls_calloc( 1, sizeof( mbedtls_x509_sequence ) );
if( seq == NULL )
ret = MBEDTLS_ERR_X509_ALLOC_FAILED;
else
ret = x509_crt_ext_key_usage_from_frame( frame, seq );
mbedtls_x509_crt_frame_release( crt );
*ext_key_usage = seq;
return( ret );
}
int mbedtls_x509_crt_get_subject( mbedtls_x509_crt const *crt,
mbedtls_x509_name **subject )
{
int ret;
mbedtls_x509_crt_frame const *frame;
mbedtls_x509_name *name;
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( ret );
name = mbedtls_calloc( 1, sizeof( mbedtls_x509_name ) );
if( name == NULL )
ret = MBEDTLS_ERR_X509_ALLOC_FAILED;
else
ret = x509_crt_subject_from_frame( frame, name );
mbedtls_x509_crt_frame_release( crt );
*subject = name;
return( ret );
}
int mbedtls_x509_crt_get_issuer( mbedtls_x509_crt const *crt,
mbedtls_x509_name **issuer )
{
int ret;
mbedtls_x509_crt_frame const *frame;
mbedtls_x509_name *name;
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( ret );
name = mbedtls_calloc( 1, sizeof( mbedtls_x509_name ) );
if( name == NULL )
ret = MBEDTLS_ERR_X509_ALLOC_FAILED;
else
ret = x509_crt_issuer_from_frame( frame, name );
mbedtls_x509_crt_frame_release( crt );
*issuer = name;
return( ret );
}
int mbedtls_x509_crt_get_frame( mbedtls_x509_crt const *crt,
mbedtls_x509_crt_frame *dst )
{
int ret;
mbedtls_x509_crt_frame const *frame;
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( ret );
*dst = *frame;
mbedtls_x509_crt_frame_release( crt );
return( 0 );
}
int mbedtls_x509_crt_get_pk( mbedtls_x509_crt const *crt,
mbedtls_pk_context *dst )
{
#if !defined(MBEDTLS_X509_ON_DEMAND_PARSING)
mbedtls_x509_buf_raw pk_raw = crt->cache->pk_raw;
return( mbedtls_pk_parse_subpubkey( &pk_raw.p,
pk_raw.p + pk_raw.len,
dst ) );
#else /* !MBEDTLS_X509_ON_DEMAND_PARSING */
int ret;
mbedtls_pk_context *pk;
ret = mbedtls_x509_crt_pk_acquire( crt, &pk );
if( ret != 0 )
return( ret );
/* Move PK from CRT cache to destination pointer
* to avoid a copy. */
*dst = *pk;
mbedtls_free( crt->cache->pk );
crt->cache->pk = NULL;
mbedtls_x509_crt_pk_release( crt );
return( 0 );
#endif /* MBEDTLS_X509_ON_DEMAND_PARSING */
}
/*
* Item in a verification chain: cert and flags for it
*/
typedef struct {
mbedtls_x509_crt *crt;
uint32_t flags;
} x509_crt_verify_chain_item;
/*
* Max size of verification chain: end-entity + intermediates + trusted root
*/
#define X509_MAX_VERIFY_CHAIN_SIZE ( MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2 )
/*
* Default profile
*/
const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default =
{
#if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_CERTIFICATES)
/* Allow SHA-1 (weak, but still safe in controlled environments) */
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA1 ) |
#endif
/* Only SHA-2 hashes */
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA224 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
0xFFFFFFF, /* Any PK alg */
0xFFFFFFF, /* Any curve */
2048,
};
/*
* Next-default profile
*/
const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next =
{
/* Hashes from SHA-256 and above */
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
0xFFFFFFF, /* Any PK alg */
#if defined(MBEDTLS_USE_TINYCRYPT)
MBEDTLS_X509_ID_FLAG( MBEDTLS_UECC_DP_SECP256R1 ),
#elif defined(MBEDTLS_ECP_C)
/* Curves at or above 128-bit security level */
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP521R1 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP256R1 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP384R1 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP512R1 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256K1 ),
#else
0,
#endif
2048,
};
/*
* NSA Suite B Profile
*/
const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb =
{
/* Only SHA-256 and 384 */
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ),
/* Only ECDSA */
MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECDSA ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECKEY ),
#if defined(MBEDTLS_USE_TINYCRYPT)
MBEDTLS_X509_ID_FLAG( MBEDTLS_UECC_DP_SECP256R1 ),
#elif defined(MBEDTLS_ECP_C)
/* Only NIST P-256 and P-384 */
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ),
#else
0,
#endif
0,
};
/*
* Check md_alg against profile
* Return 0 if md_alg is acceptable for this profile, -1 otherwise
*/
static int x509_profile_check_md_alg( const mbedtls_x509_crt_profile *profile,
mbedtls_md_type_t md_alg )
{
if( md_alg == MBEDTLS_MD_NONE )
return( -1 );
if( ( profile->allowed_mds & MBEDTLS_X509_ID_FLAG( md_alg ) ) != 0 )
return( 0 );
return( -1 );
}
/*
* Check pk_alg against profile
* Return 0 if pk_alg is acceptable for this profile, -1 otherwise
*/
static int x509_profile_check_pk_alg( const mbedtls_x509_crt_profile *profile,
mbedtls_pk_type_t pk_alg )
{
if( pk_alg == MBEDTLS_PK_NONE )
return( -1 );
if( ( profile->allowed_pks & MBEDTLS_X509_ID_FLAG( pk_alg ) ) != 0 )
return( 0 );
return( -1 );
}
/*
* Check key against profile
* Return 0 if pk is acceptable for this profile, -1 otherwise
*/
static int x509_profile_check_key( const mbedtls_x509_crt_profile *profile,
const mbedtls_pk_context *pk )
{
const mbedtls_pk_type_t pk_alg = mbedtls_pk_get_type( pk );
#if defined(MBEDTLS_RSA_C)
if( pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS )
{
if( mbedtls_pk_get_bitlen( pk ) >= profile->rsa_min_bitlen )
return( 0 );
return( -1 );
}
#endif
#if defined(MBEDTLS_USE_TINYCRYPT)
if( pk_alg == MBEDTLS_PK_ECKEY )
{
if( ( profile->allowed_curves & MBEDTLS_UECC_DP_SECP256R1 ) != 0 )
return( 0 );
return( -1 );
}
#endif /* MBEDTLS_USE_TINYCRYPT */
#if defined(MBEDTLS_ECP_C)
if( pk_alg == MBEDTLS_PK_ECDSA ||
pk_alg == MBEDTLS_PK_ECKEY ||
pk_alg == MBEDTLS_PK_ECKEY_DH )
{
const mbedtls_ecp_group_id gid = mbedtls_pk_ec( *pk )->grp.id;
if( gid == MBEDTLS_ECP_DP_NONE )
return( -1 );
if( ( profile->allowed_curves & MBEDTLS_X509_ID_FLAG( gid ) ) != 0 )
return( 0 );
return( -1 );
}
#endif
return( -1 );
}
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
/*
* Return 0 if name matches wildcard, -1 otherwise
*/
static int x509_check_wildcard( char const *cn,
size_t cn_len,
unsigned char const *buf,
size_t buf_len )
{
size_t i;
size_t cn_idx = 0;
/* We can't have a match if there is no wildcard to match */
if( buf_len < 3 || buf[0] != '*' || buf[1] != '.' )
return( -1 );
for( i = 0; i < cn_len; ++i )
{
if( cn[i] == '.' )
{
cn_idx = i;
break;
}
}
if( cn_idx == 0 )
return( -1 );
if( mbedtls_x509_memcasecmp( buf + 1, cn + cn_idx,
buf_len - 1, cn_len - cn_idx ) == 0 )
{
return( 0 );
}
return( -1 );
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
/*
* Version ::= INTEGER { v1(0), v2(1), v3(2) }
*/
static int x509_get_version( unsigned char **p,
const unsigned char *end,
int *ver )
{
int ret;
size_t len;
if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) != 0 )
{
if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
{
*ver = 0;
return( 0 );
}
return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
}
end = *p + len;
if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 )
return( MBEDTLS_ERR_X509_INVALID_VERSION + ret );
if( *p != end )
return( MBEDTLS_ERR_X509_INVALID_VERSION +
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
#if !defined(MBEDTLS_X509_CRT_REMOVE_TIME)
/*
* Validity ::= SEQUENCE {
* notBefore Time,
* notAfter Time }
*/
static int x509_get_dates( unsigned char **p,
const unsigned char *end,
mbedtls_x509_time *from,
mbedtls_x509_time *to )
{
int ret;
size_t len;
if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
return( MBEDTLS_ERR_X509_INVALID_DATE + ret );
end = *p + len;
if( ( ret = mbedtls_x509_get_time( p, end, from ) ) != 0 )
return( ret );
if( ( ret = mbedtls_x509_get_time( p, end, to ) ) != 0 )
return( ret );
if( *p != end )
return( MBEDTLS_ERR_X509_INVALID_DATE +
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
#else /* !MBEDTLS_X509_CRT_REMOVE_TIME */
static int x509_skip_dates( unsigned char **p,
const unsigned char *end )
{
int ret;
size_t len;
if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
return( MBEDTLS_ERR_X509_INVALID_DATE + ret );
/* skip contents of the sequence */
*p += len;
return( 0 );
}
#endif /* MBEDTLS_X509_CRT_REMOVE_TIME */
#if !defined(MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID)
/*
* X.509 v2/v3 unique identifier (not parsed)
*/
static int x509_get_uid( unsigned char **p,
const unsigned char *end,
mbedtls_x509_buf_raw *uid, int n )
{
int ret;
if( *p == end )
return( 0 );
if( ( ret = mbedtls_asn1_get_tag( p, end, &uid->len,
MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | n ) ) != 0 )
{
if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
return( 0 );
return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
}
uid->p = *p;
*p += uid->len;
return( 0 );
}
#else /* !MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID */
static int x509_skip_uid( unsigned char **p,
const unsigned char *end,
int n )
{
int ret;
size_t len;
if( *p == end )
return( 0 );
if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | n ) ) != 0 )
{
if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
return( 0 );
return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
}
*p += len;
return( 0 );
}
#endif /* MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID */
static int x509_get_basic_constraints( unsigned char **p,
const unsigned char *end,
int *ca_istrue,
int *max_pathlen )
{
int ret;
size_t len;
/*
* BasicConstraints ::= SEQUENCE {
* cA BOOLEAN DEFAULT FALSE,
* pathLenConstraint INTEGER (0..MAX) OPTIONAL }
*/
*ca_istrue = 0; /* DEFAULT FALSE */
*max_pathlen = 0; /* endless */
if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
return( ret );
if( *p == end )
return( 0 );
if( ( ret = mbedtls_asn1_get_bool( p, end, ca_istrue ) ) != 0 )
{
if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
ret = mbedtls_asn1_get_int( p, end, ca_istrue );
if( ret != 0 )
return( ret );
if( *ca_istrue != 0 )
*ca_istrue = 1;
}
if( *p == end )
return( 0 );
if( ( ret = mbedtls_asn1_get_int( p, end, max_pathlen ) ) != 0 )
return( ret );
if( *p != end )
return( MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
/* Do not accept max_pathlen equal to INT_MAX to avoid a signed integer
* overflow, which is an undefined behavior. */
if( *max_pathlen == INT_MAX )
return( MBEDTLS_ERR_ASN1_INVALID_LENGTH );
(*max_pathlen)++;
return( 0 );
}
static int x509_get_ns_cert_type( unsigned char **p,
const unsigned char *end,
unsigned char *ns_cert_type)
{
int ret;
mbedtls_x509_bitstring bs = { 0, 0, NULL };
if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
return( ret );
if( bs.len != 1 )
return( MBEDTLS_ERR_ASN1_INVALID_LENGTH );
/* Get actual bitstring */
*ns_cert_type = *bs.p;
return( 0 );
}
static int x509_get_key_usage( unsigned char **p,
const unsigned char *end,
uint16_t *key_usage)
{
int ret;
size_t i;
mbedtls_x509_bitstring bs = { 0, 0, NULL };
if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
return( ret );
if( bs.len < 1 )
return( MBEDTLS_ERR_ASN1_INVALID_LENGTH );
/* Get actual bitstring */
*key_usage = 0;
for( i = 0; i < bs.len && i < sizeof( *key_usage ); i++ )
{
*key_usage |= (uint16_t) bs.p[i] << ( 8*i );
}
return( 0 );
}
static int asn1_build_sequence_cb( void *ctx,
int tag,
unsigned char *data,
size_t data_len )
{
mbedtls_asn1_sequence **cur_ptr = (mbedtls_asn1_sequence **) ctx;
mbedtls_asn1_sequence *cur = *cur_ptr;
/* Allocate and assign next pointer */
if( cur->buf.p != NULL )
{
cur->next = mbedtls_calloc( 1, sizeof( mbedtls_asn1_sequence ) );
if( cur->next == NULL )
return( MBEDTLS_ERR_ASN1_ALLOC_FAILED );
cur = cur->next;
}
cur->buf.tag = tag;
cur->buf.p = data;
cur->buf.len = data_len;
*cur_ptr = cur;
return( 0 );
}
/*
* ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
*
* KeyPurposeId ::= OBJECT IDENTIFIER
*/
static int x509_get_ext_key_usage( unsigned char **p,
const unsigned char *end,
mbedtls_x509_sequence *ext_key_usage)
{
return( mbedtls_asn1_traverse_sequence_of( p, end,
0xFF, MBEDTLS_ASN1_OID,
0, 0,
asn1_build_sequence_cb,
(void *) &ext_key_usage ) );
}
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
/*
* SubjectAltName ::= GeneralNames
*
* GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
*
* GeneralName ::= CHOICE {
* otherName [0] OtherName,
* rfc822Name [1] IA5String,
* dNSName [2] IA5String,
* x400Address [3] ORAddress,
* directoryName [4] Name,
* ediPartyName [5] EDIPartyName,
* uniformResourceIdentifier [6] IA5String,
* iPAddress [7] OCTET STRING,
* registeredID [8] OBJECT IDENTIFIER }
*
* OtherName ::= SEQUENCE {
* type-id OBJECT IDENTIFIER,
* value [0] EXPLICIT ANY DEFINED BY type-id }
*
* EDIPartyName ::= SEQUENCE {
* nameAssigner [0] DirectoryString OPTIONAL,
* partyName [1] DirectoryString }
*
* NOTE: we only parse and use dNSName at this point.
*/
static int x509_get_subject_alt_name( unsigned char *p,
const unsigned char *end,
mbedtls_x509_sequence *subject_alt_name )
{
return( mbedtls_asn1_traverse_sequence_of( &p, end,
MBEDTLS_ASN1_TAG_CLASS_MASK,
MBEDTLS_ASN1_CONTEXT_SPECIFIC,
MBEDTLS_ASN1_TAG_VALUE_MASK,
2 /* SubjectAlt DNS */,
asn1_build_sequence_cb,
(void *) &subject_alt_name ) );
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
/*
* X.509 v3 extensions
*
*/
static int x509_crt_get_ext_cb( void *ctx,
int tag,
unsigned char *p,
size_t ext_len )
{
int ret;
mbedtls_x509_crt_frame *frame = (mbedtls_x509_crt_frame *) ctx;
size_t len;
unsigned char *end, *end_ext_octet;
mbedtls_x509_buf extn_oid = { 0, 0, NULL };
int is_critical = 0; /* DEFAULT FALSE */
int ext_type = 0;
((void) tag);
/*
* Extension ::= SEQUENCE {
* extnID OBJECT IDENTIFIER,
* critical BOOLEAN DEFAULT FALSE,
* extnValue OCTET STRING }
*/
end = p + ext_len;
/* Get extension ID */
if( ( ret = mbedtls_asn1_get_tag( &p, end, &extn_oid.len,
MBEDTLS_ASN1_OID ) ) != 0 )
goto err;
extn_oid.tag = MBEDTLS_ASN1_OID;
extn_oid.p = p;
p += extn_oid.len;
/* Get optional critical */
if( ( ret = mbedtls_asn1_get_bool( &p, end, &is_critical ) ) != 0 &&
( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) )
goto err;
/* Data should be octet string type */
if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
goto err;
end_ext_octet = p + len;
if( end_ext_octet != end )
{
ret = MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
goto err;
}
/*
* Detect supported extensions
*/
ret = mbedtls_oid_get_x509_ext_type( &extn_oid, &ext_type );
if( ret != 0 )
{
#if !defined(MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION)
if( is_critical )
{
/* Data is marked as critical: fail */
ret = MBEDTLS_ERR_ASN1_UNEXPECTED_TAG;
goto err;
}
#endif /* MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION */
return( 0 );
}
/* Forbid repeated extensions */
if( ( frame->ext_types & ext_type ) != 0 )
return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
frame->ext_types |= ext_type;
switch( ext_type )
{
case MBEDTLS_X509_EXT_BASIC_CONSTRAINTS:
{
int ca_istrue;
int max_pathlen;
/* Parse basic constraints */
ret = x509_get_basic_constraints( &p, end_ext_octet,
&ca_istrue,
&max_pathlen );
if( ret != 0 )
goto err;
frame->ca_istrue = ca_istrue;
frame->max_pathlen = max_pathlen;
break;
}
case MBEDTLS_X509_EXT_KEY_USAGE:
/* Parse key usage */
ret = x509_get_key_usage( &p, end_ext_octet,
&frame->key_usage );
if( ret != 0 )
goto err;
break;
case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
/* Copy reference to raw subject alt name data. */
frame->subject_alt_raw.p = p;
frame->subject_alt_raw.len = end_ext_octet - p;
ret = mbedtls_asn1_traverse_sequence_of( &p, end_ext_octet,
MBEDTLS_ASN1_TAG_CLASS_MASK,
MBEDTLS_ASN1_CONTEXT_SPECIFIC,
MBEDTLS_ASN1_TAG_VALUE_MASK,
2 /* SubjectAlt DNS */,
NULL, NULL );
if( ret != 0 )
goto err;
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
break;
case MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE:
/* Parse extended key usage */
frame->ext_key_usage_raw.p = p;
frame->ext_key_usage_raw.len = end_ext_octet - p;
if( frame->ext_key_usage_raw.len == 0 )
{
ret = MBEDTLS_ERR_ASN1_INVALID_LENGTH;
goto err;
}
/* Check structural sanity of extension. */
ret = mbedtls_asn1_traverse_sequence_of( &p, end_ext_octet,
0xFF, MBEDTLS_ASN1_OID,
0, 0, NULL, NULL );
if( ret != 0 )
goto err;
break;
case MBEDTLS_X509_EXT_NS_CERT_TYPE:
/* Parse netscape certificate type */
ret = x509_get_ns_cert_type( &p, end_ext_octet,
&frame->ns_cert_type );
if( ret != 0 )
goto err;
break;
default:
/*
* If this is a non-critical extension, which the oid layer
* supports, but there isn't an X.509 parser for it,
* skip the extension.
*/
#if !defined(MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION)
if( is_critical )
return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
#endif
p = end_ext_octet;
}
return( 0 );
err:
return( ret );
}
static int x509_crt_frame_parse_ext( mbedtls_x509_crt_frame *frame )
{
int ret;
unsigned char *p = frame->v3_ext.p;
unsigned char *end = p + frame->v3_ext.len;
if( p == end )
return( 0 );
ret = mbedtls_asn1_traverse_sequence_of( &p, end,
0xFF, MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED,
0, 0, x509_crt_get_ext_cb, frame );
if( ret == MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE )
return( ret );
if( ret == MBEDTLS_ERR_X509_INVALID_EXTENSIONS )
return( ret );
if( ret != 0 )
ret += MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
return( ret );
}
static int x509_crt_parse_frame( unsigned char *start,
unsigned char *end,
mbedtls_x509_crt_frame *frame )
{
int ret;
unsigned char *p;
size_t len;
mbedtls_x509_buf tmp;
unsigned char *tbs_start;
mbedtls_x509_buf outer_sig_alg;
size_t inner_sig_alg_len;
unsigned char *inner_sig_alg_start;
mbedtls_platform_memset( frame, 0, sizeof( *frame ) );
/*
* Certificate ::= SEQUENCE {
* tbsCertificate TBSCertificate,
* signatureAlgorithm AlgorithmIdentifier,
* signatureValue BIT STRING
* }
*
*/
p = start;
frame->raw.p = p;
if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
{
return( MBEDTLS_ERR_X509_INVALID_FORMAT );
}
/* NOTE: We are currently not checking that the `Certificate`
* structure spans the entire buffer. */
end = p + len;
frame->raw.len = end - frame->raw.p;
/*
* TBSCertificate ::= SEQUENCE { ...
*/
frame->tbs.p = p;
if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
{
return( ret + MBEDTLS_ERR_X509_INVALID_FORMAT );
}
tbs_start = p;
/* Breadth-first parsing: Jump over TBS for now. */
p += len;
frame->tbs.len = p - frame->tbs.p;
/*
* AlgorithmIdentifier ::= SEQUENCE { ...
*/
outer_sig_alg.p = p;
if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
{
return( MBEDTLS_ERR_X509_INVALID_ALG + ret );
}
p += len;
outer_sig_alg.len = p - outer_sig_alg.p;
/*
* signatureValue BIT STRING
*/
ret = mbedtls_x509_get_sig( &p, end, &tmp );
if( ret != 0 )
return( ret );
frame->sig.p = tmp.p;
frame->sig.len = tmp.len;
/* Check that we consumed the entire `Certificate` structure. */
if( p != end )
{
return( MBEDTLS_ERR_X509_INVALID_FORMAT +
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
}
/* Parse TBSCertificate structure
*
* TBSCertificate ::= SEQUENCE {
* version [0] EXPLICIT Version DEFAULT v1,
* serialNumber CertificateSerialNumber,
* signature AlgorithmIdentifier,
* issuer Name,
* validity Validity,
* subject Name,
* subjectPublicKeyInfo SubjectPublicKeyInfo,
* issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
* -- If present, version MUST be v2 or v3
* subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
* -- If present, version MUST be v2 or v3
* extensions [3] EXPLICIT Extensions OPTIONAL
* -- If present, version MUST be v3
* }
*/
end = frame->tbs.p + frame->tbs.len;
p = tbs_start;
/*
* Version ::= INTEGER { v1(0), v2(1), v3(2) }
*/
{
int version;
ret = x509_get_version( &p, end, &version );
if( ret != 0 )
return( ret );
if( version < 0 || version > 2 )
return( MBEDTLS_ERR_X509_UNKNOWN_VERSION );
frame->version = version + 1;
}
/*
* CertificateSerialNumber ::= INTEGER
*/
ret = mbedtls_x509_get_serial( &p, end, &tmp );
if( ret != 0 )
return( ret );
frame->serial.p = tmp.p;
frame->serial.len = tmp.len;
/*
* signature AlgorithmIdentifier
*/
inner_sig_alg_start = p;
ret = mbedtls_x509_get_sig_alg_raw( &p, end, &frame->sig_md,
&frame->sig_pk, NULL );
if( ret != 0 )
return( ret );
inner_sig_alg_len = p - inner_sig_alg_start;
frame->sig_alg.p = inner_sig_alg_start;
frame->sig_alg.len = inner_sig_alg_len;
/* Consistency check:
* Inner and outer AlgorithmIdentifier structures must coincide:
*
* Quoting RFC 5280, Section 4.1.1.2:
* This field MUST contain the same algorithm identifier as the
* signature field in the sequence tbsCertificate (Section 4.1.2.3).
*/
if( outer_sig_alg.len != inner_sig_alg_len ||
mbedtls_platform_memcmp( outer_sig_alg.p, inner_sig_alg_start, inner_sig_alg_len ) != 0 )
{
return( MBEDTLS_ERR_X509_SIG_MISMATCH );
}
/*
* issuer Name
*
* Name ::= CHOICE { -- only one possibility for now --
* rdnSequence RDNSequence }
*
* RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
*/
frame->issuer_raw.p = p;
ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE );
if( ret != 0 )
return( ret + MBEDTLS_ERR_X509_INVALID_FORMAT );
p += len;
frame->issuer_raw.len = p - frame->issuer_raw.p;
/* Comparing the raw buffer to itself amounts to structural validation. */
ret = mbedtls_x509_name_cmp_raw( &frame->issuer_raw,
&frame->issuer_raw,
NULL, NULL );
if( ret != 0 )
return( ret );
/*
* Validity ::= SEQUENCE { ...
*/
#if !defined(MBEDTLS_X509_CRT_REMOVE_TIME)
ret = x509_get_dates( &p, end, &frame->valid_from, &frame->valid_to );
if( ret != 0 )
return( ret );
#else /* !MBEDTLS_X509_CRT_REMOVE_TIME */
ret = x509_skip_dates( &p, end );
if( ret != 0 )
return( ret );
#endif /* MBEDTLS_X509_CRT_REMOVE_TIME */
/*
* subject Name
*
* Name ::= CHOICE { -- only one possibility for now --
* rdnSequence RDNSequence }
*
* RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
*/
frame->subject_raw.p = p;
ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE );
if( ret != 0 )
return( ret + MBEDTLS_ERR_X509_INVALID_FORMAT );
p += len;
frame->subject_raw.len = p - frame->subject_raw.p;
/* Comparing the raw buffer to itself amounts to structural validation. */
ret = mbedtls_x509_name_cmp_raw( &frame->subject_raw,
&frame->subject_raw,
NULL, NULL );
if( ret != 0 )
return( ret );
/*
* SubjectPublicKeyInfo
*/
frame->pubkey_raw.p = p;
ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE );
if( ret != 0 )
return( ret + MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
p += len;
frame->pubkey_raw.len = p - frame->pubkey_raw.p;
if( frame->version != 1 )
{
#if !defined(MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID)
/*
* issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
* -- If present, version shall be v2 or v3
*/
ret = x509_get_uid( &p, end, &frame->issuer_id, 1 /* implicit tag */ );
if( ret != 0 )
return( ret );
/*
* subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
* -- If present, version shall be v2 or v3
*/
ret = x509_get_uid( &p, end, &frame->subject_id, 2 /* implicit tag */ );
if( ret != 0 )
return( ret );
#else /* !MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID */
ret = x509_skip_uid( &p, end, 1 /* implicit tag */ );
if( ret != 0 )
return( ret );
ret = x509_skip_uid( &p, end, 2 /* implicit tag */ );
if( ret != 0 )
return( ret );
#endif /* MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID */
}
/*
* extensions [3] EXPLICIT Extensions OPTIONAL
* -- If present, version shall be v3
*/
#if !defined(MBEDTLS_X509_ALLOW_EXTENSIONS_NON_V3)
if( frame->version == 3 )
#endif
{
if( p != end )
{
ret = mbedtls_asn1_get_tag( &p, end, &len,
MBEDTLS_ASN1_CONTEXT_SPECIFIC |
MBEDTLS_ASN1_CONSTRUCTED | 3 );
if( len == 0 )
ret = MBEDTLS_ERR_ASN1_OUT_OF_DATA;
if( ret != 0 )
return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
frame->v3_ext.p = p;
frame->v3_ext.len = len;
p += len;
}
ret = x509_crt_frame_parse_ext( frame );
if( ret != 0 )
return( ret );
}
/* Wrapup: Check that we consumed the entire `TBSCertificate` structure. */
if( p != end )
{
return( MBEDTLS_ERR_X509_INVALID_FORMAT +
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
}
return( 0 );
}
static int x509_crt_subject_from_frame( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_name *subject )
{
return( mbedtls_x509_get_name( frame->subject_raw.p,
frame->subject_raw.len,
subject ) );
}
static int x509_crt_issuer_from_frame( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_name *issuer )
{
return( mbedtls_x509_get_name( frame->issuer_raw.p,
frame->issuer_raw.len,
issuer ) );
}
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
static int x509_crt_subject_alt_from_frame( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_sequence *subject_alt )
{
int ret;
unsigned char *p = frame->subject_alt_raw.p;
unsigned char *end = p + frame->subject_alt_raw.len;
mbedtls_platform_memset( subject_alt, 0, sizeof( *subject_alt ) );
if( ( frame->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME ) == 0 )
return( 0 );
ret = x509_get_subject_alt_name( p, end, subject_alt );
if( ret != 0 )
ret += MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
return( ret );
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
static int x509_crt_ext_key_usage_from_frame( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_sequence *ext_key_usage )
{
int ret;
unsigned char *p = frame->ext_key_usage_raw.p;
unsigned char *end = p + frame->ext_key_usage_raw.len;
mbedtls_platform_memset( ext_key_usage, 0, sizeof( *ext_key_usage ) );
if( ( frame->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE ) == 0 )
return( 0 );
ret = x509_get_ext_key_usage( &p, end, ext_key_usage );
if( ret != 0 )
{
ret += MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
return( ret );
}
return( 0 );
}
#if !defined(MBEDTLS_X509_ON_DEMAND_PARSING)
static int x509_crt_pk_from_frame( mbedtls_x509_crt_frame *frame,
mbedtls_pk_context *pk )
{
unsigned char *p = frame->pubkey_raw.p;
unsigned char *end = p + frame->pubkey_raw.len;
return( mbedtls_pk_parse_subpubkey( &p, end, pk ) );
}
#endif /* !MBEDTLS_X509_ON_DEMAND_PARSING */
/*
* Parse and fill a single X.509 certificate in DER format
*/
static int x509_crt_parse_der_core( mbedtls_x509_crt *crt,
const unsigned char *buf,
size_t buflen,
int make_copy )
{
int ret;
mbedtls_x509_crt_frame *frame;
mbedtls_x509_crt_cache *cache;
if( crt == NULL || buf == NULL )
return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
if( make_copy == 0 )
{
crt->raw.p = (unsigned char*) buf;
crt->raw.len = buflen;
crt->own_buffer = 0;
}
else
{
/* Call mbedtls_calloc with buflen + 1 in order to avoid potential
* return of NULL in case of length 0 certificates, which we want
* to cleanly fail with MBEDTLS_ERR_X509_INVALID_FORMAT in the
* core parsing routine, but not here. */
crt->raw.p = mbedtls_calloc( 1, buflen + 1 );
if( crt->raw.p == NULL )
return( MBEDTLS_ERR_X509_ALLOC_FAILED );
crt->raw.len = buflen;
mbedtls_platform_memcpy( crt->raw.p, buf, buflen );
crt->own_buffer = 1;
}
cache = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt_cache ) );
if( cache == NULL )
{
ret = MBEDTLS_ERR_X509_ALLOC_FAILED;
goto exit;
}
crt->cache = cache;
x509_crt_cache_init( cache );
#if defined(MBEDTLS_X509_ON_DEMAND_PARSING)
ret = mbedtls_x509_crt_cache_provide_frame( crt );
if( ret != 0 )
goto exit;
frame = crt->cache->frame;
#else /* MBEDTLS_X509_ON_DEMAND_PARSING */
frame = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt_frame ) );
if( frame == NULL )
{
ret = MBEDTLS_ERR_X509_ALLOC_FAILED;
goto exit;
}
cache->frame = frame;
ret = x509_crt_parse_frame( crt->raw.p,
crt->raw.p + crt->raw.len,
frame );
if( ret != 0 )
goto exit;
/* Copy frame to legacy CRT structure -- that's inefficient, but if
* memory matters, the new CRT structure should be used anyway. */
x509_buf_raw_to_buf( &crt->tbs, &frame->tbs );
x509_buf_raw_to_buf( &crt->serial, &frame->serial );
x509_buf_raw_to_buf( &crt->issuer_raw, &frame->issuer_raw );
x509_buf_raw_to_buf( &crt->subject_raw, &frame->subject_raw );
#if !defined(MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID)
x509_buf_raw_to_buf( &crt->issuer_id, &frame->issuer_id );
x509_buf_raw_to_buf( &crt->subject_id, &frame->subject_id );
#endif /* !MBEDTLS_X509_CRT_REMOVE_SUBJECT_ISSUER_ID */
x509_buf_raw_to_buf( &crt->pk_raw, &frame->pubkey_raw );
x509_buf_raw_to_buf( &crt->sig, &frame->sig );
x509_buf_raw_to_buf( &crt->v3_ext, &frame->v3_ext );
#if !defined(MBEDTLS_X509_CRT_REMOVE_TIME)
crt->valid_from = frame->valid_from;
crt->valid_to = frame->valid_to;
#endif /* !MBEDTLS_X509_CRT_REMOVE_TIME */
crt->version = frame->version;
crt->ca_istrue = frame->ca_istrue;
crt->max_pathlen = frame->max_pathlen;
crt->ext_types = frame->ext_types;
crt->key_usage = frame->key_usage;
crt->ns_cert_type = frame->ns_cert_type;
/*
* Obtain the remaining fields from the frame.
*/
{
/* sig_oid: Previously, needed for convenience in
* mbedtls_x509_crt_info(), now pure legacy burden. */
unsigned char *tmp = frame->sig_alg.p;
unsigned char *end = tmp + frame->sig_alg.len;
mbedtls_x509_buf sig_oid, sig_params;
ret = mbedtls_x509_get_alg( &tmp, end,
&sig_oid, &sig_params );
if( ret != 0 )
{
/* This should never happen, because we check
* the sanity of the AlgorithmIdentifier structure
* during frame parsing. */
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto exit;
}
crt->sig_oid = sig_oid;
/* Signature parameters */
tmp = frame->sig_alg.p;
ret = mbedtls_x509_get_sig_alg_raw( &tmp, end,
&crt->sig_md, &crt->sig_pk,
&crt->sig_opts );
if( ret != 0 )
{
/* Again, this should never happen. */
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto exit;
}
}
ret = x509_crt_pk_from_frame( frame, &crt->pk );
if( ret != 0 )
goto exit;
ret = x509_crt_subject_from_frame( frame, &crt->subject );
if( ret != 0 )
goto exit;
ret = x509_crt_issuer_from_frame( frame, &crt->issuer );
if( ret != 0 )
goto exit;
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
ret = x509_crt_subject_alt_from_frame( frame, &crt->subject_alt_names );
if( ret != 0 )
goto exit;
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
ret = x509_crt_ext_key_usage_from_frame( frame, &crt->ext_key_usage );
if( ret != 0 )
goto exit;
#endif /* !MBEDTLS_X509_ON_DEMAND_PARSING */
/* Currently, we accept DER encoded CRTs with trailing garbage
* and promise to not account for the garbage in the `raw` field.
*
* Note that this means that `crt->raw.len` is not necessarily the
* full size of the heap buffer allocated at `crt->raw.p` in case
* of copy-mode, but this is not a problem: freeing the buffer doesn't
* need the size, and the garbage data doesn't need zeroization. */
crt->raw.len = frame->raw.len;
cache->pk_raw = frame->pubkey_raw;
/* Free the frame before parsing the public key to
* keep peak RAM usage low. This is slightly inefficient
* because the frame will need to be parsed again on the
* first usage of the CRT, but that seems acceptable.
* As soon as the frame gets used multiple times, it
* will be cached by default. */
x509_crt_cache_clear_frame( crt->cache );
/* The cache just references the PK structure from the legacy
* implementation, so set up the latter first before setting up
* the cache.
*
* We're not actually using the parsed PK context here;
* we just parse it to check that it's well-formed. */
ret = mbedtls_x509_crt_cache_provide_pk( crt );
if( ret != 0 )
goto exit;
x509_crt_cache_clear_pk( crt->cache );
exit:
if( ret != 0 )
mbedtls_x509_crt_free( crt );
return( ret );
}
/*
* Parse one X.509 certificate in DER format from a buffer and add them to a
* chained list
*/
static int mbedtls_x509_crt_parse_der_internal( mbedtls_x509_crt *chain,
const unsigned char *buf,
size_t buflen,
int make_copy )
{
int ret;
mbedtls_x509_crt *crt = chain, *prev = NULL;
/*
* Check for valid input
*/
if( crt == NULL || buf == NULL )
return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
while( crt->raw.p != NULL && crt->next != NULL )
{
prev = crt;
crt = crt->next;
}
/*
* Add new certificate on the end of the chain if needed.
*/
if( crt->raw.p != NULL && crt->next == NULL )
{
crt->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
if( crt->next == NULL )
return( MBEDTLS_ERR_X509_ALLOC_FAILED );
prev = crt;
mbedtls_x509_crt_init( crt->next );
crt = crt->next;
}
if( ( ret = x509_crt_parse_der_core( crt, buf, buflen, make_copy ) ) != 0 )
{
if( prev )
prev->next = NULL;
if( crt != chain )
mbedtls_free( crt );
return( ret );
}
return( 0 );
}
int mbedtls_x509_crt_parse_der_nocopy( mbedtls_x509_crt *chain,
const unsigned char *buf,
size_t buflen )
{
return( mbedtls_x509_crt_parse_der_internal( chain, buf, buflen, 0 ) );
}
int mbedtls_x509_crt_parse_der( mbedtls_x509_crt *chain,
const unsigned char *buf,
size_t buflen )
{
return( mbedtls_x509_crt_parse_der_internal( chain, buf, buflen, 1 ) );
}
/*
* Parse one or more PEM certificates from a buffer and add them to the chained
* list
*/
int mbedtls_x509_crt_parse( mbedtls_x509_crt *chain,
const unsigned char *buf,
size_t buflen )
{
#if defined(MBEDTLS_PEM_PARSE_C)
int success = 0, first_error = 0, total_failed = 0;
int buf_format = MBEDTLS_X509_FORMAT_DER;
#endif
/*
* Check for valid input
*/
if( chain == NULL || buf == NULL )
return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
/*
* Determine buffer content. Buffer contains either one DER certificate or
* one or more PEM certificates.
*/
#if defined(MBEDTLS_PEM_PARSE_C)
if( buflen != 0 && buf[buflen - 1] == '\0' &&
strstr( (const char *) buf, "-----BEGIN CERTIFICATE-----" ) != NULL )
{
buf_format = MBEDTLS_X509_FORMAT_PEM;
}
if( buf_format == MBEDTLS_X509_FORMAT_DER )
return mbedtls_x509_crt_parse_der( chain, buf, buflen );
#else
return mbedtls_x509_crt_parse_der( chain, buf, buflen );
#endif
#if defined(MBEDTLS_PEM_PARSE_C)
if( buf_format == MBEDTLS_X509_FORMAT_PEM )
{
int ret;
mbedtls_pem_context pem;
/* 1 rather than 0 since the terminating NULL byte is counted in */
while( buflen > 1 )
{
size_t use_len;
mbedtls_pem_init( &pem );
/* If we get there, we know the string is null-terminated */
ret = mbedtls_pem_read_buffer( &pem,
"-----BEGIN CERTIFICATE-----",
"-----END CERTIFICATE-----",
buf, NULL, 0, &use_len );
if( ret == 0 )
{
/*
* Was PEM encoded
*/
buflen -= use_len;
buf += use_len;
}
else if( ret == MBEDTLS_ERR_PEM_BAD_INPUT_DATA )
{
return( ret );
}
else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
{
mbedtls_pem_free( &pem );
/*
* PEM header and footer were found
*/
buflen -= use_len;
buf += use_len;
if( first_error == 0 )
first_error = ret;
total_failed++;
continue;
}
else
break;
ret = mbedtls_x509_crt_parse_der( chain, pem.buf, pem.buflen );
mbedtls_pem_free( &pem );
if( ret != 0 )
{
/*
* Quit parsing on a memory error
*/
if( ret == MBEDTLS_ERR_X509_ALLOC_FAILED )
return( ret );
if( first_error == 0 )
first_error = ret;
total_failed++;
continue;
}
success = 1;
}
}
if( success )
return( total_failed );
else if( first_error )
return( first_error );
else
return( MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT );
#endif /* MBEDTLS_PEM_PARSE_C */
}
#if defined(MBEDTLS_FS_IO)
/*
* Load one or more certificates and add them to the chained list
*/
int mbedtls_x509_crt_parse_file( mbedtls_x509_crt *chain, const char *path )
{
int ret;
size_t n;
unsigned char *buf;
if( ( ret = mbedtls_pk_load_file( path, &buf, &n ) ) != 0 )
return( ret );
ret = mbedtls_x509_crt_parse( chain, buf, n );
mbedtls_platform_zeroize( buf, n );
mbedtls_free( buf );
return( ret );
}
int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
{
int ret = 0;
#if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
int w_ret;
WCHAR szDir[MAX_PATH];
char filename[MAX_PATH];
char *p;
size_t len = strlen( path );
WIN32_FIND_DATAW file_data;
HANDLE hFind;
if( len > MAX_PATH - 3 )
return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
mbedtls_platform_memset( szDir, 0, sizeof(szDir) );
mbedtls_platform_memset( filename, 0, MAX_PATH );
mbedtls_platform_memcpy( filename, path, len );
filename[len++] = '\\';
p = filename + len;
filename[len++] = '*';
w_ret = MultiByteToWideChar( CP_ACP, 0, filename, (int)len, szDir,
MAX_PATH - 3 );
if( w_ret == 0 )
return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
hFind = FindFirstFileW( szDir, &file_data );
if( hFind == INVALID_HANDLE_VALUE )
return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
len = MAX_PATH - len;
do
{
mbedtls_platform_memset( p, 0, len );
if( file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
continue;
w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
lstrlenW( file_data.cFileName ),
p, (int) len - 1,
NULL, NULL );
if( w_ret == 0 )
{
ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
goto cleanup;
}
w_ret = mbedtls_x509_crt_parse_file( chain, filename );
if( w_ret < 0 )
ret++;
else
ret += w_ret;
}
while( FindNextFileW( hFind, &file_data ) != 0 );
if( GetLastError() != ERROR_NO_MORE_FILES )
ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
cleanup:
FindClose( hFind );
#else /* _WIN32 */
int t_ret;
int snp_ret;
struct stat sb;
struct dirent *entry;
char entry_name[MBEDTLS_X509_MAX_FILE_PATH_LEN];
DIR *dir = opendir( path );
if( dir == NULL )
return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
#if defined(MBEDTLS_THREADING_C)
if( ( ret = mbedtls_mutex_lock( &mbedtls_threading_readdir_mutex ) ) != 0 )
{
closedir( dir );
return( ret );
}
#endif /* MBEDTLS_THREADING_C */
while( ( entry = readdir( dir ) ) != NULL )
{
snp_ret = mbedtls_snprintf( entry_name, sizeof entry_name,
"%s/%s", path, entry->d_name );
if( snp_ret < 0 || (size_t)snp_ret >= sizeof entry_name )
{
ret = MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
goto cleanup;
}
else if( stat( entry_name, &sb ) == -1 )
{
ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
goto cleanup;
}
if( !S_ISREG( sb.st_mode ) )
continue;
// Ignore parse errors
//
t_ret = mbedtls_x509_crt_parse_file( chain, entry_name );
if( t_ret < 0 )
ret++;
else
ret += t_ret;
}
cleanup:
closedir( dir );
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &mbedtls_threading_readdir_mutex ) != 0 )
ret = MBEDTLS_ERR_THREADING_MUTEX_ERROR;
#endif /* MBEDTLS_THREADING_C */
#endif /* _WIN32 */
return( ret );
}
#endif /* MBEDTLS_FS_IO */
typedef struct mbedtls_x509_crt_sig_info
{
mbedtls_md_type_t sig_md;
mbedtls_pk_type_t sig_pk;
void *sig_opts;
size_t crt_hash_len;
mbedtls_x509_buf_raw sig;
mbedtls_x509_buf_raw issuer_raw;
uint8_t crt_hash[MBEDTLS_MD_MAX_SIZE];
} mbedtls_x509_crt_sig_info;
static void x509_crt_free_sig_info( mbedtls_x509_crt_sig_info *info )
{
#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
mbedtls_free( info->sig_opts );
#else
((void) info);
#endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
}
static int x509_crt_get_sig_info( mbedtls_x509_crt_frame const *frame,
mbedtls_x509_crt_sig_info *info )
{
mbedtls_md_handle_t md_info;
md_info = mbedtls_md_info_from_type( frame->sig_md );
if( mbedtls_md( md_info, frame->tbs.p, frame->tbs.len,
info->crt_hash ) != 0 )
{
/* Note: this can't happen except after an internal error */
return( -1 );
}
info->crt_hash_len = mbedtls_md_get_size( md_info );
/* Make sure that this function leaves the target structure
* ready to be freed, regardless of success of failure. */
info->sig_opts = NULL;
#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
{
int ret;
unsigned char *alg_start = frame->sig_alg.p;
unsigned char *alg_end = alg_start + frame->sig_alg.len;
/* Get signature options -- currently only
* necessary for RSASSA-PSS. */
ret = mbedtls_x509_get_sig_alg_raw( &alg_start, alg_end, &info->sig_md,
&info->sig_pk, &info->sig_opts );
if( ret != 0 )
{
/* Note: this can't happen except after an internal error */
return( -1 );
}
}
#else /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
info->sig_md = frame->sig_md;
info->sig_pk = frame->sig_pk;
#endif /* !MBEDTLS_X509_RSASSA_PSS_SUPPORT */
info->issuer_raw = frame->issuer_raw;
info->sig = frame->sig;
return( 0 );
}
#if !defined(MBEDTLS_X509_REMOVE_INFO)
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
static int x509_info_subject_alt_name( char **buf, size_t *size,
const mbedtls_x509_sequence *subject_alt_name )
{
size_t i;
size_t n = *size;
char *p = *buf;
const mbedtls_x509_sequence *cur = subject_alt_name;
const char *sep = "";
size_t sep_len = 0;
while( cur != NULL )
{
if( cur->buf.len + sep_len >= n )
{
*p = '\0';
return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
}
n -= cur->buf.len + sep_len;
for( i = 0; i < sep_len; i++ )
*p++ = sep[i];
for( i = 0; i < cur->buf.len; i++ )
*p++ = cur->buf.p[i];
sep = ", ";
sep_len = 2;
cur = cur->next;
}
*p = '\0';
*size = n;
*buf = p;
return( 0 );
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
#define PRINT_ITEM(i) \
{ \
ret = mbedtls_snprintf( p, n, "%s" i, sep ); \
MBEDTLS_X509_SAFE_SNPRINTF; \
sep = ", "; \
}
#define CERT_TYPE(type,name) \
if( ns_cert_type & (type) ) \
PRINT_ITEM( name );
static int x509_info_cert_type( char **buf, size_t *size,
unsigned char ns_cert_type )
{
int ret;
size_t n = *size;
char *p = *buf;
const char *sep = "";
CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT, "SSL Client" );
CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER, "SSL Server" );
CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL, "Email" );
CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING, "Object Signing" );
CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_RESERVED, "Reserved" );
CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CA, "SSL CA" );
CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA, "Email CA" );
CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA, "Object Signing CA" );
*size = n;
*buf = p;
return( 0 );
}
#define KEY_USAGE(code,name) \
if( key_usage & (code) ) \
PRINT_ITEM( name );
static int x509_info_key_usage( char **buf, size_t *size,
unsigned int key_usage )
{
int ret;
size_t n = *size;
char *p = *buf;
const char *sep = "";
KEY_USAGE( MBEDTLS_X509_KU_DIGITAL_SIGNATURE, "Digital Signature" );
KEY_USAGE( MBEDTLS_X509_KU_NON_REPUDIATION, "Non Repudiation" );
KEY_USAGE( MBEDTLS_X509_KU_KEY_ENCIPHERMENT, "Key Encipherment" );
KEY_USAGE( MBEDTLS_X509_KU_DATA_ENCIPHERMENT, "Data Encipherment" );
KEY_USAGE( MBEDTLS_X509_KU_KEY_AGREEMENT, "Key Agreement" );
KEY_USAGE( MBEDTLS_X509_KU_KEY_CERT_SIGN, "Key Cert Sign" );
KEY_USAGE( MBEDTLS_X509_KU_CRL_SIGN, "CRL Sign" );
KEY_USAGE( MBEDTLS_X509_KU_ENCIPHER_ONLY, "Encipher Only" );
KEY_USAGE( MBEDTLS_X509_KU_DECIPHER_ONLY, "Decipher Only" );
*size = n;
*buf = p;
return( 0 );
}
static int x509_info_ext_key_usage( char **buf, size_t *size,
const mbedtls_x509_sequence *extended_key_usage )
{
int ret;
const char *desc;
size_t n = *size;
char *p = *buf;
const mbedtls_x509_sequence *cur = extended_key_usage;
const char *sep = "";
while( cur != NULL )
{
if( mbedtls_oid_get_extended_key_usage( &cur->buf, &desc ) != 0 )
desc = "???";
ret = mbedtls_snprintf( p, n, "%s%s", sep, desc );
MBEDTLS_X509_SAFE_SNPRINTF;
sep = ", ";
cur = cur->next;
}
*size = n;
*buf = p;
return( 0 );
}
/*
* Return an informational string about the certificate.
*/
#define BEFORE_COLON_CRT 18
#define BC_CRT "18"
int mbedtls_x509_crt_info( char *buf, size_t size, const char *prefix,
const mbedtls_x509_crt *crt )
{
int ret;
size_t n;
char *p;
char key_size_str[BEFORE_COLON_CRT];
mbedtls_x509_crt_frame frame;
mbedtls_pk_context pk;
mbedtls_x509_name *issuer = NULL, *subject = NULL;
mbedtls_x509_sequence *ext_key_usage = NULL;
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
mbedtls_x509_sequence *subject_alt_names = NULL;
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
mbedtls_x509_crt_sig_info sig_info;
p = buf;
n = size;
memset( &sig_info, 0, sizeof( mbedtls_x509_crt_sig_info ) );
mbedtls_pk_init( &pk );
if( NULL == crt )
{
ret = mbedtls_snprintf( p, n, "\nCertificate is uninitialised!\n" );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
return( (int) ( size - n ) );
}
ret = mbedtls_x509_crt_get_frame( crt, &frame );
if( ret != 0 )
{
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto cleanup;
}
ret = mbedtls_x509_crt_get_subject( crt, &subject );
if( ret != 0 )
{
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto cleanup;
}
ret = mbedtls_x509_crt_get_issuer( crt, &issuer );
if( ret != 0 )
{
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto cleanup;
}
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
ret = mbedtls_x509_crt_get_subject_alt_names( crt, &subject_alt_names );
if( ret != 0 )
{
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto cleanup;
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
ret = mbedtls_x509_crt_get_ext_key_usage( crt, &ext_key_usage );
if( ret != 0 )
{
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto cleanup;
}
ret = mbedtls_x509_crt_get_pk( crt, &pk );
if( ret != 0 )
{
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto cleanup;
}
ret = x509_crt_get_sig_info( &frame, &sig_info );
if( ret != 0 )
{
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
goto cleanup;
}
ret = mbedtls_snprintf( p, n, "%scert. version : %d\n",
prefix, frame.version );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
{
mbedtls_x509_buf serial;
serial.p = frame.serial.p;
serial.len = frame.serial.len;
ret = mbedtls_snprintf( p, n, "%sserial number : ",
prefix );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
ret = mbedtls_x509_serial_gets( p, n, &serial );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
}
ret = mbedtls_snprintf( p, n, "\n%sissuer name : ", prefix );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
ret = mbedtls_x509_dn_gets( p, n, issuer );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
ret = mbedtls_snprintf( p, n, "\n%ssubject name : ", prefix );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
ret = mbedtls_x509_dn_gets( p, n, subject );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
#if !defined(MBEDTLS_X509_CRT_REMOVE_TIME)
ret = mbedtls_snprintf( p, n, "\n%sissued on : " \
"%04d-%02d-%02d %02d:%02d:%02d", prefix,
frame.valid_from.year, frame.valid_from.mon,
frame.valid_from.day, frame.valid_from.hour,
frame.valid_from.min, frame.valid_from.sec );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
ret = mbedtls_snprintf( p, n, "\n%sexpires on : " \
"%04d-%02d-%02d %02d:%02d:%02d", prefix,
frame.valid_to.year, frame.valid_to.mon,
frame.valid_to.day, frame.valid_to.hour,
frame.valid_to.min, frame.valid_to.sec );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
#endif /* MBEDTLS_X509_CRT_REMOVE_TIME */
ret = mbedtls_snprintf( p, n, "\n%ssigned using : ", prefix );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
ret = mbedtls_x509_sig_alg_gets( p, n, sig_info.sig_pk,
sig_info.sig_md, sig_info.sig_opts );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
/* Key size */
if( ( ret = mbedtls_x509_key_size_helper( key_size_str, BEFORE_COLON_CRT,
mbedtls_pk_get_name( &pk ) ) ) != 0 )
{
return( ret );
}
ret = mbedtls_snprintf( p, n, "\n%s%-" BC_CRT "s: %d bits", prefix, key_size_str,
(int) mbedtls_pk_get_bitlen( &pk ) );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
/*
* Optional extensions
*/
if( frame.ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS )
{
ret = mbedtls_snprintf( p, n, "\n%sbasic constraints : CA=%s", prefix,
frame.ca_istrue ? "true" : "false" );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
if( frame.max_pathlen > 0 )
{
ret = mbedtls_snprintf( p, n, ", max_pathlen=%d", frame.max_pathlen - 1 );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
}
}
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
if( frame.ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
{
ret = mbedtls_snprintf( p, n, "\n%ssubject alt name : ", prefix );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
if( ( ret = x509_info_subject_alt_name( &p, &n,
subject_alt_names ) ) != 0 )
return( ret );
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
if( frame.ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE )
{
ret = mbedtls_snprintf( p, n, "\n%scert. type : ", prefix );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
if( ( ret = x509_info_cert_type( &p, &n, frame.ns_cert_type ) ) != 0 )
return( ret );
}
if( frame.ext_types & MBEDTLS_X509_EXT_KEY_USAGE )
{
ret = mbedtls_snprintf( p, n, "\n%skey usage : ", prefix );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
if( ( ret = x509_info_key_usage( &p, &n, frame.key_usage ) ) != 0 )
return( ret );
}
if( frame.ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE )
{
ret = mbedtls_snprintf( p, n, "\n%sext key usage : ", prefix );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
if( ( ret = x509_info_ext_key_usage( &p, &n,
ext_key_usage ) ) != 0 )
return( ret );
}
ret = mbedtls_snprintf( p, n, "\n" );
MBEDTLS_X509_SAFE_SNPRINTF_WITH_CLEANUP;
ret = (int) ( size - n );
cleanup:
x509_crt_free_sig_info( &sig_info );
mbedtls_pk_free( &pk );
mbedtls_x509_name_free( issuer );
mbedtls_x509_name_free( subject );
mbedtls_x509_sequence_free( ext_key_usage );
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
mbedtls_x509_sequence_free( subject_alt_names );
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
return( ret );
}
struct x509_crt_verify_string {
int code;
const char *string;
};
static const struct x509_crt_verify_string x509_crt_verify_strings[] = {
{ MBEDTLS_X509_BADCERT_EXPIRED, "The certificate validity has expired" },
{ MBEDTLS_X509_BADCERT_REVOKED, "The certificate has been revoked (is on a CRL)" },
{ MBEDTLS_X509_BADCERT_CN_MISMATCH, "The certificate Common Name (CN) does not match with the expected CN" },
{ MBEDTLS_X509_BADCERT_NOT_TRUSTED, "The certificate is not correctly signed by the trusted CA" },
{ MBEDTLS_X509_BADCRL_NOT_TRUSTED, "The CRL is not correctly signed by the trusted CA" },
{ MBEDTLS_X509_BADCRL_EXPIRED, "The CRL is expired" },
{ MBEDTLS_X509_BADCERT_MISSING, "Certificate was missing" },
{ MBEDTLS_X509_BADCERT_SKIP_VERIFY, "Certificate verification was skipped" },
{ MBEDTLS_X509_BADCERT_OTHER, "Other reason (can be used by verify callback)" },
{ MBEDTLS_X509_BADCERT_FUTURE, "The certificate validity starts in the future" },
{ MBEDTLS_X509_BADCRL_FUTURE, "The CRL is from the future" },
{ MBEDTLS_X509_BADCERT_KEY_USAGE, "Usage does not match the keyUsage extension" },
{ MBEDTLS_X509_BADCERT_EXT_KEY_USAGE, "Usage does not match the extendedKeyUsage extension" },
{ MBEDTLS_X509_BADCERT_NS_CERT_TYPE, "Usage does not match the nsCertType extension" },
{ MBEDTLS_X509_BADCERT_BAD_MD, "The certificate is signed with an unacceptable hash." },
{ MBEDTLS_X509_BADCERT_BAD_PK, "The certificate is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
{ MBEDTLS_X509_BADCERT_BAD_KEY, "The certificate is signed with an unacceptable key (eg bad curve, RSA too short)." },
{ MBEDTLS_X509_BADCRL_BAD_MD, "The CRL is signed with an unacceptable hash." },
{ MBEDTLS_X509_BADCRL_BAD_PK, "The CRL is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
{ MBEDTLS_X509_BADCRL_BAD_KEY, "The CRL is signed with an unacceptable key (eg bad curve, RSA too short)." },
{ 0, NULL }
};
int mbedtls_x509_crt_verify_info( char *buf, size_t size, const char *prefix,
uint32_t flags )
{
int ret;
const struct x509_crt_verify_string *cur;
char *p = buf;
size_t n = size;
for( cur = x509_crt_verify_strings; cur->string != NULL ; cur++ )
{
if( ( flags & cur->code ) == 0 )
continue;
ret = mbedtls_snprintf( p, n, "%s%s\n", prefix, cur->string );
MBEDTLS_X509_SAFE_SNPRINTF;
flags ^= cur->code;
}
if( flags != 0 )
{
ret = mbedtls_snprintf( p, n, "%sUnknown reason "
"(this should not happen)\n", prefix );
MBEDTLS_X509_SAFE_SNPRINTF;
}
return( (int) ( size - n ) );
}
#endif /* !MBEDTLS_X509_REMOVE_INFO */
#if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
static int x509_crt_check_key_usage_frame( const mbedtls_x509_crt_frame *crt,
unsigned int usage )
{
unsigned int usage_must, usage_may;
unsigned int may_mask = MBEDTLS_X509_KU_ENCIPHER_ONLY
| MBEDTLS_X509_KU_DECIPHER_ONLY;
if( ( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE ) == 0 )
return( 0 );
usage_must = usage & ~may_mask;
if( ( ( crt->key_usage & ~may_mask ) & usage_must ) != usage_must )
return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
usage_may = usage & may_mask;
if( ( ( crt->key_usage & may_mask ) | usage_may ) != usage_may )
return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
return( 0 );
}
int mbedtls_x509_crt_check_key_usage( const mbedtls_x509_crt *crt,
unsigned int usage )
{
int ret;
mbedtls_x509_crt_frame const *frame;
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
ret = x509_crt_check_key_usage_frame( frame, usage );
mbedtls_x509_crt_frame_release( crt );
return( ret );
}
#endif
#if defined(MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE)
typedef struct
{
const char *oid;
size_t oid_len;
} x509_crt_check_ext_key_usage_cb_ctx_t;
static int x509_crt_check_ext_key_usage_cb( void *ctx,
int tag,
unsigned char *data,
size_t data_len )
{
x509_crt_check_ext_key_usage_cb_ctx_t *cb_ctx =
(x509_crt_check_ext_key_usage_cb_ctx_t *) ctx;
((void) tag);
if( MBEDTLS_OID_CMP_RAW( MBEDTLS_OID_ANY_EXTENDED_KEY_USAGE,
data, data_len ) == 0 )
{
return( 1 );
}
if( data_len == cb_ctx->oid_len && mbedtls_platform_memcmp( data, cb_ctx->oid,
data_len ) == 0 )
{
return( 1 );
}
return( 0 );
}
int mbedtls_x509_crt_check_extended_key_usage( const mbedtls_x509_crt *crt,
const char *usage_oid,
size_t usage_len )
{
int ret;
mbedtls_x509_crt_frame const *frame;
unsigned ext_types;
unsigned char *p, *end;
x509_crt_check_ext_key_usage_cb_ctx_t cb_ctx = { usage_oid, usage_len };
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
/* Extension is not mandatory, absent means no restriction */
ext_types = frame->ext_types;
if( ( ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE ) != 0 )
{
p = frame->ext_key_usage_raw.p;
end = p + frame->ext_key_usage_raw.len;
ret = mbedtls_asn1_traverse_sequence_of( &p, end,
0xFF, MBEDTLS_ASN1_OID, 0, 0,
x509_crt_check_ext_key_usage_cb,
&cb_ctx );
if( ret == 1 )
ret = 0;
else
ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
}
mbedtls_x509_crt_frame_release( crt );
return( ret );
}
#endif /* MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE */
#if defined(MBEDTLS_X509_CRL_PARSE_C)
/*
* Return 1 if the certificate is revoked, or 0 otherwise.
*/
static int x509_serial_is_revoked( unsigned char const *serial,
size_t serial_len,
const mbedtls_x509_crl *crl )
{
const mbedtls_x509_crl_entry *cur = &crl->entry;
while( cur != NULL && cur->serial.len != 0 )
{
if( serial_len == cur->serial.len &&
mbedtls_platform_memcmp( serial, cur->serial.p, serial_len ) == 0 )
{
if( mbedtls_x509_time_is_past( &cur->revocation_date ) )
return( 1 );
}
cur = cur->next;
}
return( 0 );
}
int mbedtls_x509_crt_is_revoked( const mbedtls_x509_crt *crt,
const mbedtls_x509_crl *crl )
{
int ret;
mbedtls_x509_crt_frame const *frame;
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
ret = x509_serial_is_revoked( frame->serial.p,
frame->serial.len,
crl );
mbedtls_x509_crt_frame_release( crt );
return( ret );
}
/*
* Check that the given certificate is not revoked according to the CRL.
* Skip validation if no CRL for the given CA is present.
*/
static int x509_crt_verifycrl( unsigned char *crt_serial,
size_t crt_serial_len,
mbedtls_x509_crt *ca_crt,
mbedtls_x509_crl *crl_list,
const mbedtls_x509_crt_profile *profile )
{
int ret;
int flags = 0;
unsigned char hash[MBEDTLS_MD_MAX_SIZE];
mbedtls_md_handle_t md_info;
mbedtls_x509_buf_raw ca_subject;
mbedtls_pk_context *pk;
int can_sign;
if( ca_crt == NULL )
return( flags );
{
mbedtls_x509_crt_frame const *ca;
ret = mbedtls_x509_crt_frame_acquire( ca_crt, &ca );
if( ret != 0 )
return( MBEDTLS_X509_BADCRL_NOT_TRUSTED );
ca_subject = ca->subject_raw;
can_sign = 0;
if( x509_crt_check_key_usage_frame( ca,
MBEDTLS_X509_KU_CRL_SIGN ) == 0 )
{
can_sign = 1;
}
mbedtls_x509_crt_frame_release( ca_crt );
}
ret = mbedtls_x509_crt_pk_acquire( ca_crt, &pk );
if( ret != 0 )
return( MBEDTLS_X509_BADCRL_NOT_TRUSTED );
while( crl_list != NULL )
{
if( crl_list->version == 0 ||
mbedtls_x509_name_cmp_raw( &crl_list->issuer_raw,
&ca_subject, NULL, NULL ) != 0 )
{
crl_list = crl_list->next;
continue;
}
/*
* Check if the CA is configured to sign CRLs
*/
#if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
if( !can_sign )
{
flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
break;
}
#endif
/*
* Check if CRL is correctly signed by the trusted CA
*/
if( x509_profile_check_md_alg( profile, crl_list->sig_md ) != 0 )
flags |= MBEDTLS_X509_BADCRL_BAD_MD;
if( x509_profile_check_pk_alg( profile, crl_list->sig_pk ) != 0 )
flags |= MBEDTLS_X509_BADCRL_BAD_PK;
md_info = mbedtls_md_info_from_type( crl_list->sig_md );
if( mbedtls_md( md_info, crl_list->tbs.p, crl_list->tbs.len, hash ) != 0 )
{
/* Note: this can't happen except after an internal error */
flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
break;
}
if( x509_profile_check_key( profile, pk ) != 0 )
flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
if( mbedtls_pk_verify_ext( crl_list->sig_pk, crl_list->sig_opts, pk,
crl_list->sig_md, hash, mbedtls_md_get_size( md_info ),
crl_list->sig.p, crl_list->sig.len ) != 0 )
{
flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
break;
}
/*
* Check for validity of CRL (Do not drop out)
*/
if( mbedtls_x509_time_is_past( &crl_list->next_update ) )
flags |= MBEDTLS_X509_BADCRL_EXPIRED;
if( mbedtls_x509_time_is_future( &crl_list->this_update ) )
flags |= MBEDTLS_X509_BADCRL_FUTURE;
/*
* Check if certificate is revoked
*/
if( x509_serial_is_revoked( crt_serial, crt_serial_len,
crl_list ) )
{
flags |= MBEDTLS_X509_BADCERT_REVOKED;
break;
}
crl_list = crl_list->next;
}
mbedtls_x509_crt_pk_release( ca_crt );
return( flags );
}
#endif /* MBEDTLS_X509_CRL_PARSE_C */
/*
* Check the signature of a certificate by its parent
*/
static int x509_crt_check_signature( const mbedtls_x509_crt_sig_info *sig_info,
mbedtls_x509_crt *parent,
mbedtls_x509_crt_restart_ctx *rs_ctx )
{
int ret;
mbedtls_pk_context *pk;
ret = mbedtls_x509_crt_pk_acquire( parent, &pk );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
/* Skip expensive computation on obvious mismatch */
if( ! mbedtls_pk_can_do( pk, sig_info->sig_pk ) )
{
ret = -1;
goto exit;
}
#if !( defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE) )
((void) rs_ctx);
#else
if( rs_ctx != NULL && sig_info->sig_pk == MBEDTLS_PK_ECDSA )
{
ret = mbedtls_pk_verify_restartable( pk,
sig_info->sig_md,
sig_info->crt_hash, sig_info->crt_hash_len,
sig_info->sig.p, sig_info->sig.len,
&rs_ctx->pk );
}
else
#endif
{
ret = mbedtls_pk_verify_ext( sig_info->sig_pk,
sig_info->sig_opts,
pk,
sig_info->sig_md,
sig_info->crt_hash, sig_info->crt_hash_len,
sig_info->sig.p, sig_info->sig.len );
}
exit:
mbedtls_x509_crt_pk_release( parent );
return( ret );
}
/*
* Check if 'parent' is a suitable parent (signing CA) for 'child'.
* Return 0 if yes, -1 if not.
*
* top means parent is a locally-trusted certificate
*/
static int x509_crt_check_parent( const mbedtls_x509_crt_sig_info *sig_info,
const mbedtls_x509_crt_frame *parent,
int top )
{
int need_ca_bit;
/* Parent must be the issuer */
if( mbedtls_x509_name_cmp_raw( &sig_info->issuer_raw,
&parent->subject_raw,
NULL, NULL ) != 0 )
{
return( -1 );
}
/* Parent must have the basicConstraints CA bit set as a general rule */
need_ca_bit = 1;
/* Exception: v1/v2 certificates that are locally trusted. */
if( top && parent->version < 3 )
need_ca_bit = 0;
if( need_ca_bit && ! parent->ca_istrue )
return( -1 );
#if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
if( need_ca_bit &&
x509_crt_check_key_usage_frame( parent,
MBEDTLS_X509_KU_KEY_CERT_SIGN ) != 0 )
{
return( -1 );
}
#endif
return( 0 );
}
/* This value is different enough from 0 that it's hard for an active physical
* attacker to reach it just by flipping a few bits. */
#define X509_SIGNATURE_IS_GOOD 0x7f5a5a5a
/*
* Find a suitable parent for child in candidates, or return NULL.
*
* Here suitable is defined as:
* 1. subject name matches child's issuer
* 2. if necessary, the CA bit is set and key usage allows signing certs
* 3. for trusted roots, the signature is correct
* (for intermediates, the signature is checked and the result reported)
* 4. pathlen constraints are satisfied
*
* If there's a suitable candidate which is also time-valid, return the first
* such. Otherwise, return the first suitable candidate (or NULL if there is
* none).
*
* The rationale for this rule is that someone could have a list of trusted
* roots with two versions on the same root with different validity periods.
* (At least one user reported having such a list and wanted it to just work.)
* The reason we don't just require time-validity is that generally there is
* only one version, and if it's expired we want the flags to state that
* rather than NOT_TRUSTED, as would be the case if we required it here.
*
* The rationale for rule 3 (signature for trusted roots) is that users might
* have two versions of the same CA with different keys in their list, and the
* way we select the correct one is by checking the signature (as we don't
* rely on key identifier extensions). (This is one way users might choose to
* handle key rollover, another relies on self-issued certs, see [SIRO].)
*
* Arguments:
* - [in] child: certificate for which we're looking for a parent
* - [in] candidates: chained list of potential parents
* - [out] r_parent: parent found (or NULL)
* - [out] r_signature_is_good: set to X509_SIGNATURE_IS_GOOD if
* child signature by parent is valid, or to 0
* - [in] top: 1 if candidates consists of trusted roots, ie we're at the top
* of the chain, 0 otherwise
* - [in] path_cnt: number of intermediates seen so far
* - [in] self_cnt: number of self-signed intermediates seen so far
* (will never be greater than path_cnt)
* - [in-out] rs_ctx: context for restarting operations
*
* Return value:
* - 0 on success
* - MBEDTLS_ERR_ECP_IN_PROGRESS or MBEDTLS_ERR_PLATFORM_FAULT_DETECTED otherwise
*/
static int x509_crt_find_parent_in(
mbedtls_x509_crt_sig_info const *child_sig,
mbedtls_x509_crt *candidates,
mbedtls_x509_crt **r_parent,
int *r_signature_is_good,
int top,
unsigned path_cnt,
unsigned self_cnt,
mbedtls_x509_crt_restart_ctx *rs_ctx )
{
int ret;
volatile int ret_fi = MBEDTLS_ERR_PLATFORM_FAULT_DETECTED;
mbedtls_x509_crt *parent_crt;
int signature_is_good = 0;
#if defined(MBEDTLS_HAVE_TIME_DATE)
mbedtls_x509_crt *fallback_parent;
int fallback_signature_is_good;
#endif /* MBEDTLS_HAVE_TIME_DATE */
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/* did we have something in progress? */
if( rs_ctx != NULL && rs_ctx->parent != NULL )
{
/* restore saved state */
parent_crt = rs_ctx->parent;
#if defined(MBEDTLS_HAVE_TIME_DATE)
fallback_parent = rs_ctx->fallback_parent;
fallback_signature_is_good = rs_ctx->fallback_signature_is_good;
#endif /* MBEDTLS_HAVE_TIME_DATE */
/* clear saved state */
rs_ctx->parent = NULL;
#if defined(MBEDTLS_HAVE_TIME_DATE)
rs_ctx->fallback_parent = NULL;
rs_ctx->fallback_signature_is_good = 0;
#endif /* MBEDTLS_HAVE_TIME_DATE */
/* resume where we left */
goto check_signature;
}
#endif
#if defined(MBEDTLS_HAVE_TIME_DATE)
fallback_parent = NULL;
fallback_signature_is_good = 0;
#endif /* MBEDTLS_HAVE_TIME_DATE */
for( parent_crt = candidates; parent_crt != NULL;
parent_crt = parent_crt->next )
{
int parent_valid, parent_match, path_len_ok;
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
check_signature:
#endif
parent_valid = parent_match = path_len_ok = 0;
{
mbedtls_x509_crt_frame const *parent;
ret = mbedtls_x509_crt_frame_acquire( parent_crt, &parent );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
#if !defined(MBEDTLS_X509_CRT_REMOVE_TIME)
if( !mbedtls_x509_time_is_past( &parent->valid_to ) &&
!mbedtls_x509_time_is_future( &parent->valid_from ) )
#endif /* !MBEDTLS_X509_CRT_REMOVE_TIME */
{
parent_valid = 1;
}
/* basic parenting skills (name, CA bit, key usage) */
if( x509_crt_check_parent( child_sig, parent, top ) == 0 )
parent_match = 1;
/* +1 because the stored max_pathlen is 1 higher
* than the actual value */
if( !( parent->max_pathlen > 0 &&
(size_t) parent->max_pathlen < 1 + path_cnt - self_cnt ) )
{
path_len_ok = 1;
}
mbedtls_x509_crt_frame_release( parent_crt );
}
if( parent_match == 0 || path_len_ok == 0 )
continue;
/* Signature */
ret_fi = x509_crt_check_signature( child_sig, parent_crt, rs_ctx );
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
if( rs_ctx != NULL && ret_fi == MBEDTLS_ERR_ECP_IN_PROGRESS )
{
/* save state */
rs_ctx->parent = parent_crt;
#if defined(MBEDTLS_HAVE_TIME_DATE)
rs_ctx->fallback_parent = fallback_parent;
rs_ctx->fallback_signature_is_good = fallback_signature_is_good;
#endif /* MBEDTLS_HAVE_TIME_DATE */
return( ret_fi );
}
#endif
if( ret_fi == 0 )
{
mbedtls_platform_random_delay();
if( ret_fi == 0 )
signature_is_good = X509_SIGNATURE_IS_GOOD;
else
return( MBEDTLS_ERR_PLATFORM_FAULT_DETECTED );
}
if( top && ! signature_is_good )
continue;
/* optional time check */
if( !parent_valid )
{
#if defined(MBEDTLS_HAVE_TIME_DATE)
if( fallback_parent == NULL )
{
fallback_parent = parent_crt;
fallback_signature_is_good = signature_is_good;
}
#endif /* MBEDTLS_HAVE_TIME_DATE */
continue;
}
*r_parent = parent_crt;
*r_signature_is_good = signature_is_good;
break;
}
if( parent_crt == NULL )
{
#if defined(MBEDTLS_HAVE_TIME_DATE)
*r_parent = fallback_parent;
*r_signature_is_good = fallback_signature_is_good;
#else /* MBEDTLS_HAVE_TIME_DATE */
*r_parent = NULL;
#endif /* !MBEDTLS_HAVE_TIME_DATE */
}
return( 0 );
}
/*
* Find a parent in trusted CAs or the provided chain, or return NULL.
*
* Searches in trusted CAs first, and return the first suitable parent found
* (see find_parent_in() for definition of suitable).
*
* Arguments:
* - [in] child: certificate for which we're looking for a parent, followed
* by a chain of possible intermediates
* - [in] trust_ca: list of locally trusted certificates
* - [out] parent: parent found (or NULL)
* - [out] parent_is_trusted: 1 if returned `parent` is trusted, or 0
* - [out] signature_is_good: 1 if child signature by parent is valid, or 0
* - [in] path_cnt: number of links in the chain so far (EE -> ... -> child)
* - [in] self_cnt: number of self-signed certs in the chain so far
* (will always be no greater than path_cnt)
* - [in-out] rs_ctx: context for restarting operations
*
* Return value:
* - 0 on success
* - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
*/
static int x509_crt_find_parent(
mbedtls_x509_crt_sig_info const *child_sig,
mbedtls_x509_crt *rest,
mbedtls_x509_crt *trust_ca,
mbedtls_x509_crt **parent,
int *parent_is_trusted,
int *signature_is_good,
unsigned path_cnt,
unsigned self_cnt,
mbedtls_x509_crt_restart_ctx *rs_ctx )
{
int ret;
mbedtls_x509_crt *search_list;
*parent_is_trusted = 1;
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/* restore then clear saved state if we have some stored */
if( rs_ctx != NULL && rs_ctx->parent_is_trusted != -1 )
{
*parent_is_trusted = rs_ctx->parent_is_trusted;
rs_ctx->parent_is_trusted = -1;
}
#endif
while( 1 ) {
search_list = *parent_is_trusted ? trust_ca : rest;
ret = x509_crt_find_parent_in( child_sig, search_list,
parent, signature_is_good,
*parent_is_trusted,
path_cnt, self_cnt, rs_ctx );
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
{
/* save state */
rs_ctx->parent_is_trusted = *parent_is_trusted;
return( ret );
}
#else
(void) ret;
#endif
/* stop here if found or already in second iteration */
if( *parent != NULL || *parent_is_trusted == 0 )
break;
/* prepare second iteration */
*parent_is_trusted = 0;
}
/* extra precaution against mistakes in the caller */
if( *parent == NULL )
{
*parent_is_trusted = 0;
*signature_is_good = 0;
}
return( 0 );
}
/*
* Check if an end-entity certificate is locally trusted
*
* Currently we require such certificates to be self-signed (actually only
* check for self-issued as self-signatures are not checked)
*/
static int x509_crt_check_ee_locally_trusted(
mbedtls_x509_crt_frame const *crt,
mbedtls_x509_crt const *trust_ca )
{
mbedtls_x509_crt const *cur;
/* look for an exact match with trusted cert */
for( cur = trust_ca; cur != NULL; cur = cur->next )
{
if( crt->raw.len == cur->raw.len &&
mbedtls_platform_memcmp( crt->raw.p, cur->raw.p, crt->raw.len ) == 0 )
{
return( 0 );
}
}
/* too bad */
return( -1 );
}
#if !defined(MBEDTLS_X509_REMOVE_VERIFY_CALLBACK)
/*
* Reset (init or clear) a verify_chain
*/
static void x509_crt_verify_chain_reset(
mbedtls_x509_crt_verify_chain *ver_chain )
{
size_t i;
for( i = 0; i < MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE; i++ )
{
ver_chain->items[i].crt = NULL;
ver_chain->items[i].flags = (uint32_t) -1;
}
ver_chain->len = 0;
}
/*
* Merge the flags for all certs in the chain, after calling callback
*/
static int x509_crt_verify_chain_get_flags(
const mbedtls_x509_crt_verify_chain *ver_chain,
uint32_t *flags,
int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
void *p_vrfy )
{
int ret;
unsigned i;
uint32_t cur_flags;
const mbedtls_x509_crt_verify_chain_item *cur;
for( i = ver_chain->len; i != 0; --i )
{
cur = &ver_chain->items[i-1];
cur_flags = cur->flags;
if( NULL != f_vrfy )
if( ( ret = f_vrfy( p_vrfy, cur->crt, (int) i-1, &cur_flags ) ) != 0 )
return( ret );
*flags |= cur_flags;
}
return( 0 );
}
static void x509_crt_verify_chain_add_ee_flags(
mbedtls_x509_crt_verify_chain *chain,
uint32_t ee_flags )
{
chain->items[0].flags |= ee_flags;
}
static void x509_crt_verify_chain_add_crt(
mbedtls_x509_crt_verify_chain *chain,
mbedtls_x509_crt *crt )
{
mbedtls_x509_crt_verify_chain_item *cur;
cur = &chain->items[chain->len];
cur->crt = crt;
cur->flags = 0;
chain->len++;
}
static uint32_t* x509_crt_verify_chain_get_cur_flags(
mbedtls_x509_crt_verify_chain *chain )
{
return( &chain->items[chain->len - 1].flags );
}
static unsigned x509_crt_verify_chain_len(
mbedtls_x509_crt_verify_chain const *chain )
{
return( chain->len );
}
#else /* !MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
/*
* Reset (init or clear) a verify_chain
*/
static void x509_crt_verify_chain_reset(
mbedtls_x509_crt_verify_chain *ver_chain )
{
ver_chain->len = 0;
ver_chain->flags = 0;
}
/*
* Merge the flags for all certs in the chain, after calling callback
*/
static int x509_crt_verify_chain_get_flags(
const mbedtls_x509_crt_verify_chain *ver_chain,
uint32_t *flags,
int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
void *p_vrfy )
{
((void) f_vrfy);
((void) p_vrfy);
*flags = ver_chain->flags;
return( 0 );
}
static void x509_crt_verify_chain_add_ee_flags(
mbedtls_x509_crt_verify_chain *chain,
uint32_t ee_flags )
{
chain->flags |= ee_flags;
}
static void x509_crt_verify_chain_add_crt(
mbedtls_x509_crt_verify_chain *chain,
mbedtls_x509_crt *crt )
{
((void) crt);
chain->len++;
}
static uint32_t* x509_crt_verify_chain_get_cur_flags(
mbedtls_x509_crt_verify_chain *chain )
{
return( &chain->flags );
}
static unsigned x509_crt_verify_chain_len(
mbedtls_x509_crt_verify_chain const *chain )
{
return( chain->len );
}
#endif /* MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
/*
* This is used in addition to the flag for a specific issue, to ensure that
* it is not possible for an active physical attacker to entirely clear the
* flags just by flipping a single bit. Take advantage of the fact that all
* values defined in include/mbedtls/x509.h so far are 24-bit or less, so the
* top byte is free.
*
* Currently this protection is not compatible with the vrfy callback (as it
* can observ and modify flags freely), so it's only enabled when the callback
* is disabled.
*/
#if defined(MBEDTLS_X509_REMOVE_VERIFY_CALLBACK)
#define X509_BADCERT_FI_EXTRA 0xff000000u
#else
#define X509_BADCERT_FI_EXTRA 0u
#endif
/*
* Build and verify a certificate chain
*
* Given a peer-provided list of certificates EE, C1, ..., Cn and
* a list of trusted certs R1, ... Rp, try to build and verify a chain
* EE, Ci1, ... Ciq [, Rj]
* such that every cert in the chain is a child of the next one,
* jumping to a trusted root as early as possible.
*
* Verify that chain and return it with flags for all issues found.
*
* Special cases:
* - EE == Rj -> return a one-element list containing it
* - EE, Ci1, ..., Ciq cannot be continued with a trusted root
* -> return that chain with NOT_TRUSTED set on Ciq
*
* Tests for (aspects of) this function should include at least:
* - trusted EE
* - EE -> trusted root
* - EE -> intermediate CA -> trusted root
* - if relevant: EE untrusted
* - if relevant: EE -> intermediate, untrusted
* with the aspect under test checked at each relevant level (EE, int, root).
* For some aspects longer chains are required, but usually length 2 is
* enough (but length 1 is not in general).
*
* Arguments:
* - [in] crt: the cert list EE, C1, ..., Cn
* - [in] trust_ca: the trusted list R1, ..., Rp
* - [in] ca_crl, profile: as in verify_with_profile()
* - [out] ver_chain: the built and verified chain
* Only valid when return value is 0, may contain garbage otherwise!
* Restart note: need not be the same when calling again to resume.
* - [in-out] rs_ctx: context for restarting operations
*
* Return value:
* - non-zero if the chain could not be fully built and examined
* - 0 is the chain was successfully built and examined,
* even if it was found to be invalid
*/
static int x509_crt_verify_chain(
mbedtls_x509_crt *crt,
mbedtls_x509_crt *trust_ca,
mbedtls_x509_crl *ca_crl,
const mbedtls_x509_crt_profile *profile,
mbedtls_x509_crt_verify_chain *ver_chain,
mbedtls_x509_crt_restart_ctx *rs_ctx )
{
/* Don't initialize any of those variables here, so that the compiler can
* catch potential issues with jumping ahead when restarting */
int ret;
uint32_t *flags;
mbedtls_x509_crt *child_crt;
mbedtls_x509_crt *parent_crt;
int parent_is_trusted;
int child_is_trusted;
int signature_is_good;
volatile int signature_is_good_fi;
unsigned self_cnt;
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/* resume if we had an operation in progress */
if( rs_ctx != NULL && rs_ctx->in_progress == x509_crt_rs_find_parent )
{
/* restore saved state */
*ver_chain = rs_ctx->ver_chain; /* struct copy */
self_cnt = rs_ctx->self_cnt;
child_crt = rs_ctx->cur_crt;
child_is_trusted = 0;
goto find_parent;
}
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
child_crt = crt;
self_cnt = 0;
parent_is_trusted = 0;
child_is_trusted = 0;
while( 1 ) {
#if defined(MBEDTLS_X509_CRL_PARSE_C)
mbedtls_x509_buf_raw child_serial;
#endif /* MBEDTLS_X509_CRL_PARSE_C */
int self_issued;
/* Add certificate to the verification chain */
x509_crt_verify_chain_add_crt( ver_chain, child_crt );
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
find_parent:
#endif
flags = x509_crt_verify_chain_get_cur_flags( ver_chain );
{
mbedtls_x509_crt_sig_info child_sig;
{
mbedtls_x509_crt_frame const *child;
ret = mbedtls_x509_crt_frame_acquire( child_crt, &child );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
#if !defined(MBEDTLS_X509_CRT_REMOVE_TIME)
/* Check time-validity (all certificates) */
if( mbedtls_x509_time_is_past( &child->valid_to ) )
*flags |= MBEDTLS_X509_BADCERT_EXPIRED | X509_BADCERT_FI_EXTRA;
if( mbedtls_x509_time_is_future( &child->valid_from ) )
*flags |= MBEDTLS_X509_BADCERT_FUTURE | X509_BADCERT_FI_EXTRA;
#endif /* !MBEDTLS_X509_CRT_REMOVE_TIME */
/* Stop here for trusted roots (but not for trusted EE certs) */
if( child_is_trusted )
{
mbedtls_x509_crt_frame_release( child_crt );
return( 0 );
}
self_issued = 0;
if( mbedtls_x509_name_cmp_raw( &child->issuer_raw,
&child->subject_raw,
NULL, NULL ) == 0 )
{
self_issued = 1;
}
/* Check signature algorithm: MD & PK algs */
if( x509_profile_check_md_alg( profile, child->sig_md ) != 0 )
*flags |= MBEDTLS_X509_BADCERT_BAD_MD | X509_BADCERT_FI_EXTRA;
if( x509_profile_check_pk_alg( profile, child->sig_pk ) != 0 )
*flags |= MBEDTLS_X509_BADCERT_BAD_PK | X509_BADCERT_FI_EXTRA;
/* Special case: EE certs that are locally trusted */
if( x509_crt_verify_chain_len( ver_chain ) == 1 && self_issued &&
x509_crt_check_ee_locally_trusted( child, trust_ca ) == 0 )
{
mbedtls_x509_crt_frame_release( child_crt );
return( 0 );
}
#if defined(MBEDTLS_X509_CRL_PARSE_C)
child_serial = child->serial;
#endif /* MBEDTLS_X509_CRL_PARSE_C */
ret = x509_crt_get_sig_info( child, &child_sig );
mbedtls_x509_crt_frame_release( child_crt );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
}
/* Look for a parent in trusted CAs or up the chain */
ret = x509_crt_find_parent( &child_sig, child_crt->next,
trust_ca, &parent_crt,
&parent_is_trusted, &signature_is_good,
x509_crt_verify_chain_len( ver_chain ) - 1,
self_cnt, rs_ctx );
x509_crt_free_sig_info( &child_sig );
}
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
{
/* save state */
rs_ctx->in_progress = x509_crt_rs_find_parent;
rs_ctx->self_cnt = self_cnt;
rs_ctx->ver_chain = *ver_chain; /* struct copy */
rs_ctx->cur_crt = child_crt;
return( ret );
}
#else
(void) ret;
#endif
/* No parent? We're done here */
if( parent_crt == NULL )
{
*flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED | X509_BADCERT_FI_EXTRA;
return( 0 );
}
/* Count intermediate self-issued (not necessarily self-signed) certs.
* These can occur with some strategies for key rollover, see [SIRO],
* and should be excluded from max_pathlen checks. */
if( x509_crt_verify_chain_len( ver_chain ) != 1 && self_issued )
self_cnt++;
/* path_cnt is 0 for the first intermediate CA,
* and if parent is trusted it's not an intermediate CA */
if( ! parent_is_trusted &&
x509_crt_verify_chain_len( ver_chain ) >
MBEDTLS_X509_MAX_INTERMEDIATE_CA )
{
/* return immediately to avoid overflow the chain array */
return( MBEDTLS_ERR_X509_FATAL_ERROR );
}
/* signature was checked while searching parent */
signature_is_good_fi = signature_is_good;
if( signature_is_good_fi != X509_SIGNATURE_IS_GOOD )
*flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED | X509_BADCERT_FI_EXTRA;
mbedtls_platform_random_delay();
if( signature_is_good_fi != X509_SIGNATURE_IS_GOOD )
*flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED | X509_BADCERT_FI_EXTRA;
{
mbedtls_pk_context *parent_pk;
ret = mbedtls_x509_crt_pk_acquire( parent_crt, &parent_pk );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
/* check size of signing key */
if( x509_profile_check_key( profile, parent_pk ) != 0 )
*flags |= MBEDTLS_X509_BADCERT_BAD_KEY | X509_BADCERT_FI_EXTRA;
mbedtls_x509_crt_pk_release( parent_crt );
}
#if defined(MBEDTLS_X509_CRL_PARSE_C)
/* Check trusted CA's CRL for the given crt */
*flags |= x509_crt_verifycrl( child_serial.p,
child_serial.len,
parent_crt, ca_crl, profile );
#else
(void) ca_crl;
#endif
/* prepare for next iteration */
child_crt = parent_crt;
parent_crt = NULL;
child_is_trusted = parent_is_trusted;
signature_is_good = 0;
}
}
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
/*
* Check for CN match
*/
static int x509_crt_check_cn( unsigned char const *buf,
size_t buflen,
const char *cn,
size_t cn_len )
{
/* Try exact match */
if( mbedtls_x509_memcasecmp( cn, buf, buflen, cn_len ) == 0 )
return( 0 );
/* try wildcard match */
if( x509_check_wildcard( cn, cn_len, buf, buflen ) == 0 )
{
return( 0 );
}
return( -1 );
}
/* Returns 1 on a match and 0 on a mismatch.
* This is because this function is used as a callback for
* mbedtls_x509_name_cmp_raw(), which continues the name
* traversal as long as the callback returns 0. */
static int x509_crt_check_name( void *ctx,
mbedtls_x509_buf *oid,
mbedtls_x509_buf *val,
int next_merged )
{
char const *cn = (char const*) ctx;
size_t cn_len = strlen( cn );
((void) next_merged);
if( MBEDTLS_OID_CMP( MBEDTLS_OID_AT_CN, oid ) == 0 &&
x509_crt_check_cn( val->p, val->len, cn, cn_len ) == 0 )
{
return( 1 );
}
return( 0 );
}
/* Returns 1 on a match and 0 on a mismatch.
* This is because this function is used as a callback for
* mbedtls_asn1_traverse_sequence_of(), which continues the
* traversal as long as the callback returns 0. */
static int x509_crt_subject_alt_check_name( void *ctx,
int tag,
unsigned char *data,
size_t data_len )
{
char const *cn = (char const*) ctx;
size_t cn_len = strlen( cn );
((void) tag);
if( x509_crt_check_cn( data, data_len, cn, cn_len ) == 0 )
return( 1 );
return( 0 );
}
/*
* Verify the requested CN - only call this if cn is not NULL!
*/
static int x509_crt_verify_name( const mbedtls_x509_crt *crt,
const char *cn,
uint32_t *flags )
{
int ret;
mbedtls_x509_crt_frame const *frame;
ret = mbedtls_x509_crt_frame_acquire( crt, &frame );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
if( frame->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
{
unsigned char *p =
frame->subject_alt_raw.p;
const unsigned char *end =
frame->subject_alt_raw.p + frame->subject_alt_raw.len;
ret = mbedtls_asn1_traverse_sequence_of( &p, end,
MBEDTLS_ASN1_TAG_CLASS_MASK,
MBEDTLS_ASN1_CONTEXT_SPECIFIC,
MBEDTLS_ASN1_TAG_VALUE_MASK,
2 /* SubjectAlt DNS */,
x509_crt_subject_alt_check_name,
(void *) cn );
}
else
{
ret = mbedtls_x509_name_cmp_raw( &frame->subject_raw,
&frame->subject_raw,
x509_crt_check_name, (void *) cn );
}
mbedtls_x509_crt_frame_release( crt );
/* x509_crt_check_name() and x509_crt_subject_alt_check_name()
* return 1 when finding a name component matching `cn`. */
if( ret == 1 )
return( 0 );
if( ret != 0 )
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
*flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH | X509_BADCERT_FI_EXTRA;
return( ret );
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
/*
* Verify the certificate validity (default profile, not restartable)
*/
int mbedtls_x509_crt_verify( mbedtls_x509_crt *crt,
mbedtls_x509_crt *trust_ca,
mbedtls_x509_crl *ca_crl,
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
const char *cn,
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
uint32_t *flags
#if !defined(MBEDTLS_X509_REMOVE_VERIFY_CALLBACK)
, int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *)
, void *p_vrfy
#endif /* MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
)
{
return( mbedtls_x509_crt_verify_restartable( crt, trust_ca, ca_crl,
&mbedtls_x509_crt_profile_default,
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
cn,
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
flags,
#if !defined(MBEDTLS_X509_REMOVE_VERIFY_CALLBACK)
f_vrfy, p_vrfy,
#endif /* !MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
NULL ) );
}
/*
* Verify the certificate validity (user-chosen profile, not restartable)
*/
int mbedtls_x509_crt_verify_with_profile( mbedtls_x509_crt *crt,
mbedtls_x509_crt *trust_ca,
mbedtls_x509_crl *ca_crl,
const mbedtls_x509_crt_profile *profile,
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
const char *cn,
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
uint32_t *flags
#if !defined(MBEDTLS_X509_REMOVE_VERIFY_CALLBACK)
, int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *)
, void *p_vrfy
#endif /* MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
)
{
return( mbedtls_x509_crt_verify_restartable( crt, trust_ca, ca_crl,
profile,
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
cn,
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
flags,
#if !defined(MBEDTLS_X509_REMOVE_VERIFY_CALLBACK)
f_vrfy, p_vrfy,
#endif /* !MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
NULL ) );
}
/*
* Verify the certificate validity, with profile, restartable version
*
* This function:
* - checks the requested CN (if any)
* - checks the type and size of the EE cert's key,
* as that isn't done as part of chain building/verification currently
* - builds and verifies the chain
* - then calls the callback and merges the flags
*/
int mbedtls_x509_crt_verify_restartable( mbedtls_x509_crt *crt,
mbedtls_x509_crt *trust_ca,
mbedtls_x509_crl *ca_crl,
const mbedtls_x509_crt_profile *profile,
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
const char *cn,
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
uint32_t *flags,
#if !defined(MBEDTLS_X509_REMOVE_VERIFY_CALLBACK)
int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
void *p_vrfy,
#endif /* !MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
mbedtls_x509_crt_restart_ctx *rs_ctx )
{
int ret;
mbedtls_x509_crt_verify_chain ver_chain;
uint32_t ee_flags;
volatile uint32_t flags_fi = (uint32_t) -1;
*flags = 0;
ee_flags = 0;
x509_crt_verify_chain_reset( &ver_chain );
if( profile == NULL )
{
ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
goto exit;
}
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
/* check name if requested */
if( cn != NULL )
{
ret = x509_crt_verify_name( crt, cn, &ee_flags );
if( ret != 0 )
return( ret );
}
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
{
mbedtls_pk_context *pk;
mbedtls_pk_type_t pk_type;
ret = mbedtls_x509_crt_pk_acquire( crt, &pk );
if( ret != 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
/* Check the type and size of the key */
pk_type = mbedtls_pk_get_type( pk );
if( x509_profile_check_pk_alg( profile, pk_type ) != 0 )
ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK | X509_BADCERT_FI_EXTRA;
if( x509_profile_check_key( profile, pk ) != 0 )
ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY | X509_BADCERT_FI_EXTRA;
mbedtls_x509_crt_pk_release( crt );
}
/* Check the chain */
ret = x509_crt_verify_chain( crt, trust_ca, ca_crl, profile,
&ver_chain, rs_ctx );
if( ret != 0 )
goto exit;
/* Merge end-entity flags */
x509_crt_verify_chain_add_ee_flags( &ver_chain, ee_flags );
/* Build final flags, calling callback on the way if any */
#if !defined(MBEDTLS_X509_REMOVE_VERIFY_CALLBACK)
ret = x509_crt_verify_chain_get_flags( &ver_chain, flags, f_vrfy, p_vrfy );
#else
ret = x509_crt_verify_chain_get_flags( &ver_chain, flags, NULL, NULL );
#endif /* MBEDTLS_X509_REMOVE_VERIFY_CALLBACK */
exit:
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
if( rs_ctx != NULL && ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
mbedtls_x509_crt_restart_free( rs_ctx );
#endif
/* prevent misuse of the vrfy callback - VERIFY_FAILED would be ignored by
* the SSL module for authmode optional, but non-zero return from the
* callback means a fatal error so it shouldn't be ignored */
if( ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED )
ret = MBEDTLS_ERR_X509_FATAL_ERROR;
if( ret != 0 )
{
*flags = (uint32_t) -1;
return( ret );
}
flags_fi = *flags;
if( flags_fi == 0 )
{
mbedtls_platform_random_delay();
if( flags_fi == 0 )
return( 0 );
else
return( MBEDTLS_ERR_PLATFORM_FAULT_DETECTED );
}
/* Preserve the API by removing internal extra bits - from now on the
* fact that flags is non-zero is also redundantly encoded by the
* non-zero return value from this function. */
*flags &= ~ X509_BADCERT_FI_EXTRA;
return( MBEDTLS_ERR_X509_CERT_VERIFY_FAILED );
}
/*
* Initialize a certificate chain
*/
void mbedtls_x509_crt_init( mbedtls_x509_crt *crt )
{
memset( crt, 0, sizeof(mbedtls_x509_crt) );
}
/*
* Unallocate all certificate data
*/
void mbedtls_x509_crt_free( mbedtls_x509_crt *crt )
{
mbedtls_x509_crt *cert_cur = crt;
mbedtls_x509_crt *cert_prv;
if( crt == NULL )
return;
do
{
x509_crt_cache_free( cert_cur->cache );
mbedtls_free( cert_cur->cache );
#if !defined(MBEDTLS_X509_ON_DEMAND_PARSING)
mbedtls_pk_free( &cert_cur->pk );
#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
mbedtls_free( cert_cur->sig_opts );
#endif
mbedtls_x509_name_free( cert_cur->issuer.next );
mbedtls_x509_name_free( cert_cur->subject.next );
mbedtls_x509_sequence_free( cert_cur->ext_key_usage.next );
#if !defined(MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION)
mbedtls_x509_sequence_free( cert_cur->subject_alt_names.next );
#endif /* !MBEDTLS_X509_REMOVE_HOSTNAME_VERIFICATION */
#endif /* !MBEDTLS_X509_ON_DEMAND_PARSING */
if( cert_cur->raw.p != NULL && cert_cur->own_buffer )
{
mbedtls_platform_zeroize( cert_cur->raw.p, cert_cur->raw.len );
mbedtls_free( cert_cur->raw.p );
}
cert_cur = cert_cur->next;
}
while( cert_cur != NULL );
cert_cur = crt;
do
{
cert_prv = cert_cur;
cert_cur = cert_cur->next;
mbedtls_platform_zeroize( cert_prv, sizeof( mbedtls_x509_crt ) );
if( cert_prv != crt )
mbedtls_free( cert_prv );
}
while( cert_cur != NULL );
}
#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
/*
* Initialize a restart context
*/
void mbedtls_x509_crt_restart_init( mbedtls_x509_crt_restart_ctx *ctx )
{
mbedtls_pk_restart_init( &ctx->pk );
ctx->parent = NULL;
#if defined(MBEDTLS_HAVE_TIME_DATE)
ctx->fallback_parent = NULL;
ctx->fallback_signature_is_good = 0;
#endif /* MBEDTLS_HAVE_TIME_DATE */
ctx->parent_is_trusted = -1;
ctx->in_progress = x509_crt_rs_none;
ctx->self_cnt = 0;
x509_crt_verify_chain_reset( &ctx->ver_chain );
}
/*
* Free the components of a restart context
*/
void mbedtls_x509_crt_restart_free( mbedtls_x509_crt_restart_ctx *ctx )
{
if( ctx == NULL )
return;
mbedtls_pk_restart_free( &ctx->pk );
mbedtls_x509_crt_restart_init( ctx );
}
#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
int mbedtls_x509_crt_frame_acquire( mbedtls_x509_crt const *crt,
mbedtls_x509_crt_frame const **dst )
{
int ret = 0;
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_lock( &crt->cache->frame_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif /* MBEDTLS_THREADING_C */
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
if( crt->cache->frame_readers == 0 )
#endif
ret = mbedtls_x509_crt_cache_provide_frame( crt );
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
if( crt->cache->frame_readers == MBEDTLS_X509_CACHE_FRAME_READERS_MAX )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
crt->cache->frame_readers++;
#endif
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &crt->cache->frame_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif /* MBEDTLS_THREADING_C */
*dst = crt->cache->frame;
return( ret );
}
int mbedtls_x509_crt_frame_release( mbedtls_x509_crt const *crt )
{
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_lock( &crt->cache->frame_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif /* MBEDTLS_THREADING_C */
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
if( crt->cache->frame_readers == 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
crt->cache->frame_readers--;
#endif
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_unlock( &crt->cache->frame_mutex );
#endif /* MBEDTLS_THREADING_C */
#if defined(MBEDTLS_X509_ALWAYS_FLUSH)
(void) mbedtls_x509_crt_flush_cache_frame( crt );
#endif /* MBEDTLS_X509_ALWAYS_FLUSH */
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) && \
!defined(MBEDTLS_THREADING_C)
((void) crt);
#endif
return( 0 );
}
int mbedtls_x509_crt_pk_acquire( mbedtls_x509_crt const *crt,
mbedtls_pk_context **dst )
{
int ret = 0;
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_lock( &crt->cache->pk_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif /* MBEDTLS_THREADING_C */
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
if( crt->cache->pk_readers == 0 )
#endif
ret = mbedtls_x509_crt_cache_provide_pk( crt );
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
if( crt->cache->pk_readers == MBEDTLS_X509_CACHE_PK_READERS_MAX )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
crt->cache->pk_readers++;
#endif
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_unlock( &crt->cache->pk_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif /* MBEDTLS_THREADING_C */
*dst = crt->cache->pk;
return( ret );
}
int mbedtls_x509_crt_pk_release( mbedtls_x509_crt const *crt )
{
#if defined(MBEDTLS_THREADING_C)
if( mbedtls_mutex_lock( &crt->cache->pk_mutex ) != 0 )
return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
#endif /* MBEDTLS_THREADING_C */
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) || \
defined(MBEDTLS_THREADING_C)
if( crt->cache->pk_readers == 0 )
return( MBEDTLS_ERR_X509_FATAL_ERROR );
crt->cache->pk_readers--;
#endif
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_unlock( &crt->cache->pk_mutex );
#endif /* MBEDTLS_THREADING_C */
#if defined(MBEDTLS_X509_ALWAYS_FLUSH)
(void) mbedtls_x509_crt_flush_cache_pk( crt );
#endif /* MBEDTLS_X509_ALWAYS_FLUSH */
#if !defined(MBEDTLS_X509_ALWAYS_FLUSH) && \
!defined(MBEDTLS_THREADING_C)
((void) crt);
#endif
return( 0 );
}
#endif /* MBEDTLS_X509_CRT_PARSE_C */
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