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/*
* X.509 base functions for creating certificates / CSRs
*
* Copyright The Mbed TLS Contributors
* 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.
*/
#include "common.h"
#if defined(MBEDTLS_X509_CREATE_C)
#include "mbedtls/x509.h"
#include "mbedtls/asn1write.h"
#include "mbedtls/error.h"
#include "mbedtls/oid.h"
#include <string.h>
/* Structure linking OIDs for X.509 DN AttributeTypes to their
* string representations and default string encodings used by Mbed TLS. */
typedef struct {
const char *name; /* String representation of AttributeType, e.g.
* "CN" or "emailAddress". */
size_t name_len; /* Length of 'name', without trailing 0 byte. */
const char *oid; /* String representation of OID of AttributeType,
* as per RFC 5280, Appendix A.1. */
int default_tag; /* The default character encoding used for the
* given attribute type, e.g.
* MBEDTLS_ASN1_UTF8_STRING for UTF-8. */
} x509_attr_descriptor_t;
#define ADD_STRLEN( s ) s, sizeof( s ) - 1
/* X.509 DN attributes from RFC 5280, Appendix A.1. */
static const x509_attr_descriptor_t x509_attrs[] =
{
{ ADD_STRLEN( "CN" ),
MBEDTLS_OID_AT_CN, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "commonName" ),
MBEDTLS_OID_AT_CN, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "C" ),
MBEDTLS_OID_AT_COUNTRY, MBEDTLS_ASN1_PRINTABLE_STRING },
{ ADD_STRLEN( "countryName" ),
MBEDTLS_OID_AT_COUNTRY, MBEDTLS_ASN1_PRINTABLE_STRING },
{ ADD_STRLEN( "O" ),
MBEDTLS_OID_AT_ORGANIZATION, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "organizationName" ),
MBEDTLS_OID_AT_ORGANIZATION, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "L" ),
MBEDTLS_OID_AT_LOCALITY, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "locality" ),
MBEDTLS_OID_AT_LOCALITY, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "R" ),
MBEDTLS_OID_PKCS9_EMAIL, MBEDTLS_ASN1_IA5_STRING },
{ ADD_STRLEN( "OU" ),
MBEDTLS_OID_AT_ORG_UNIT, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "organizationalUnitName" ),
MBEDTLS_OID_AT_ORG_UNIT, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "ST" ),
MBEDTLS_OID_AT_STATE, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "stateOrProvinceName" ),
MBEDTLS_OID_AT_STATE, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "emailAddress" ),
MBEDTLS_OID_PKCS9_EMAIL, MBEDTLS_ASN1_IA5_STRING },
{ ADD_STRLEN( "serialNumber" ),
MBEDTLS_OID_AT_SERIAL_NUMBER, MBEDTLS_ASN1_PRINTABLE_STRING },
{ ADD_STRLEN( "postalAddress" ),
MBEDTLS_OID_AT_POSTAL_ADDRESS, MBEDTLS_ASN1_PRINTABLE_STRING },
{ ADD_STRLEN( "postalCode" ),
MBEDTLS_OID_AT_POSTAL_CODE, MBEDTLS_ASN1_PRINTABLE_STRING },
{ ADD_STRLEN( "dnQualifier" ),
MBEDTLS_OID_AT_DN_QUALIFIER, MBEDTLS_ASN1_PRINTABLE_STRING },
{ ADD_STRLEN( "title" ),
MBEDTLS_OID_AT_TITLE, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "surName" ),
MBEDTLS_OID_AT_SUR_NAME, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "SN" ),
MBEDTLS_OID_AT_SUR_NAME, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "givenName" ),
MBEDTLS_OID_AT_GIVEN_NAME, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "GN" ),
MBEDTLS_OID_AT_GIVEN_NAME, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "initials" ),
MBEDTLS_OID_AT_INITIALS, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "pseudonym" ),
MBEDTLS_OID_AT_PSEUDONYM, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "generationQualifier" ),
MBEDTLS_OID_AT_GENERATION_QUALIFIER, MBEDTLS_ASN1_UTF8_STRING },
{ ADD_STRLEN( "domainComponent" ),
MBEDTLS_OID_DOMAIN_COMPONENT, MBEDTLS_ASN1_IA5_STRING },
{ ADD_STRLEN( "DC" ),
MBEDTLS_OID_DOMAIN_COMPONENT, MBEDTLS_ASN1_IA5_STRING },
{ NULL, 0, NULL, MBEDTLS_ASN1_NULL }
};
static const x509_attr_descriptor_t *x509_attr_descr_from_name( const char *name, size_t name_len )
{
const x509_attr_descriptor_t *cur;
for( cur = x509_attrs; cur->name != NULL; cur++ )
if( cur->name_len == name_len &&
strncmp( cur->name, name, name_len ) == 0 )
break;
if ( cur->name == NULL )
return( NULL );
return( cur );
}
int mbedtls_x509_string_to_names( mbedtls_asn1_named_data **head, const char *name )
{
int ret = 0;
const char *s = name, *c = s;
const char *end = s + strlen( s );
const char *oid = NULL;
const x509_attr_descriptor_t* attr_descr = NULL;
int in_tag = 1;
char data[MBEDTLS_X509_MAX_DN_NAME_SIZE];
char *d = data;
/* Clear existing chain if present */
mbedtls_asn1_free_named_data_list( head );
while( c <= end )
{
if( in_tag && *c == '=' )
{
if( ( attr_descr = x509_attr_descr_from_name( s, c - s ) ) == NULL )
{
ret = MBEDTLS_ERR_X509_UNKNOWN_OID;
goto exit;
}
oid = attr_descr->oid;
s = c + 1;
in_tag = 0;
d = data;
}
if( !in_tag && *c == '\\' && c != end )
{
c++;
/* Check for valid escaped characters */
if( c == end || *c != ',' )
{
ret = MBEDTLS_ERR_X509_INVALID_NAME;
goto exit;
}
}
else if( !in_tag && ( *c == ',' || c == end ) )
{
mbedtls_asn1_named_data* cur =
mbedtls_asn1_store_named_data( head, oid, strlen( oid ),
(unsigned char *) data,
d - data );
if(cur == NULL )
{
return( MBEDTLS_ERR_X509_ALLOC_FAILED );
}
// set tagType
cur->val.tag = attr_descr->default_tag;
while( c < end && *(c + 1) == ' ' )
c++;
s = c + 1;
in_tag = 1;
}
if( !in_tag && s != c + 1 )
{
*(d++) = *c;
if( d - data == MBEDTLS_X509_MAX_DN_NAME_SIZE )
{
ret = MBEDTLS_ERR_X509_INVALID_NAME;
goto exit;
}
}
c++;
}
exit:
return( ret );
}
/* The first byte of the value in the mbedtls_asn1_named_data structure is reserved
* to store the critical boolean for us
*/
int mbedtls_x509_set_extension( mbedtls_asn1_named_data **head, const char *oid, size_t oid_len,
int critical, const unsigned char *val, size_t val_len )
{
mbedtls_asn1_named_data *cur;
if( ( cur = mbedtls_asn1_store_named_data( head, oid, oid_len,
NULL, val_len + 1 ) ) == NULL )
{
return( MBEDTLS_ERR_X509_ALLOC_FAILED );
}
cur->val.p[0] = critical;
memcpy( cur->val.p + 1, val, val_len );
return( 0 );
}
/*
* RelativeDistinguishedName ::=
* SET OF AttributeTypeAndValue
*
* AttributeTypeAndValue ::= SEQUENCE {
* type AttributeType,
* value AttributeValue }
*
* AttributeType ::= OBJECT IDENTIFIER
*
* AttributeValue ::= ANY DEFINED BY AttributeType
*/
static int x509_write_name( unsigned char **p, unsigned char *start, mbedtls_asn1_named_data* cur_name)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len = 0;
const char *oid = (const char*)cur_name->oid.p;
size_t oid_len = cur_name->oid.len;
const unsigned char *name = cur_name->val.p;
size_t name_len = cur_name->val.len;
// Write correct string tag and value
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tagged_string( p, start,
cur_name->val.tag,
(const char *) name,
name_len ) );
// Write OID
//
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_oid( p, start, oid,
oid_len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start,
MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SEQUENCE ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start,
MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SET ) );
return( (int) len );
}
int mbedtls_x509_write_names( unsigned char **p, unsigned char *start,
mbedtls_asn1_named_data *first )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len = 0;
mbedtls_asn1_named_data *cur = first;
while( cur != NULL )
{
MBEDTLS_ASN1_CHK_ADD( len, x509_write_name( p, start, cur ) );
cur = cur->next;
}
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SEQUENCE ) );
return( (int) len );
}
int mbedtls_x509_write_sig( unsigned char **p, unsigned char *start,
const char *oid, size_t oid_len,
unsigned char *sig, size_t size )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len = 0;
if( *p < start || (size_t)( *p - start ) < size )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
len = size;
(*p) -= len;
memcpy( *p, sig, len );
if( *p - start < 1 )
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
*--(*p) = 0;
len += 1;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_BIT_STRING ) );
// Write OID
//
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_algorithm_identifier( p, start, oid,
oid_len, 0 ) );
return( (int) len );
}
static int x509_write_extension( unsigned char **p, unsigned char *start,
mbedtls_asn1_named_data *ext )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len = 0;
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start, ext->val.p + 1,
ext->val.len - 1 ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, ext->val.len - 1 ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_OCTET_STRING ) );
if( ext->val.p[0] != 0 )
{
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_bool( p, start, 1 ) );
}
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start, ext->oid.p,
ext->oid.len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, ext->oid.len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_OID ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) );
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED |
MBEDTLS_ASN1_SEQUENCE ) );
return( (int) len );
}
/*
* Extension ::= SEQUENCE {
* extnID OBJECT IDENTIFIER,
* critical BOOLEAN DEFAULT FALSE,
* extnValue OCTET STRING
* -- contains the DER encoding of an ASN.1 value
* -- corresponding to the extension type identified
* -- by extnID
* }
*/
int mbedtls_x509_write_extensions( unsigned char **p, unsigned char *start,
mbedtls_asn1_named_data *first )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len = 0;
mbedtls_asn1_named_data *cur_ext = first;
while( cur_ext != NULL )
{
MBEDTLS_ASN1_CHK_ADD( len, x509_write_extension( p, start, cur_ext ) );
cur_ext = cur_ext->next;
}
return( (int) len );
}
#endif /* MBEDTLS_X509_CREATE_C */
|