mbedtls/library/x509write.c
2013-09-12 11:57:02 +02:00

1200 lines
35 KiB
C

/*
* X509 buffer writing functionality
*
* Copyright (C) 2006-2013, Brainspark B.V.
*
* This file is part of PolarSSL (http://www.polarssl.org)
* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/*
* References:
* - certificates: RFC 5280, updated by RFC 6818
* - CSRs: PKCS#10 v1.7 aka RFC 2986
* - attributes: PKCS#9 v2.0 aka RFC 2985
*/
#include "polarssl/config.h"
#if defined(POLARSSL_X509_WRITE_C)
#include "polarssl/asn1write.h"
#include "polarssl/x509write.h"
#include "polarssl/x509.h"
#include "polarssl/md.h"
#include "polarssl/oid.h"
#include "polarssl/sha1.h"
#if defined(POLARSSL_BASE64_C)
#include "polarssl/base64.h"
#endif
#if defined(POLARSSL_MEMORY_C)
#include "polarssl/memory.h"
#else
#include <stdlib.h>
#define polarssl_malloc malloc
#define polarssl_free free
#endif
static int x509write_string_to_names( asn1_named_data **head, char *name )
{
int ret = 0;
char *s = name, *c = s;
char *end = s + strlen( s );
char *oid = NULL;
int in_tag = 1;
asn1_named_data *cur;
/* Clear existing chain if present */
asn1_free_named_data_list( head );
while( c <= end )
{
if( in_tag && *c == '=' )
{
if( memcmp( s, "CN", 2 ) == 0 && c - s == 2 )
oid = OID_AT_CN;
else if( memcmp( s, "C", 1 ) == 0 && c - s == 1 )
oid = OID_AT_COUNTRY;
else if( memcmp( s, "O", 1 ) == 0 && c - s == 1 )
oid = OID_AT_ORGANIZATION;
else if( memcmp( s, "L", 1 ) == 0 && c - s == 1 )
oid = OID_AT_LOCALITY;
else if( memcmp( s, "R", 1 ) == 0 && c - s == 1 )
oid = OID_PKCS9_EMAIL;
else if( memcmp( s, "OU", 2 ) == 0 && c - s == 2 )
oid = OID_AT_ORG_UNIT;
else if( memcmp( s, "ST", 2 ) == 0 && c - s == 2 )
oid = OID_AT_STATE;
else
{
ret = POLARSSL_ERR_X509WRITE_UNKNOWN_OID;
goto exit;
}
s = c + 1;
in_tag = 0;
}
if( !in_tag && ( *c == ',' || c == end ) )
{
if( ( cur = asn1_store_named_data( head, oid, strlen( oid ),
(unsigned char *) s,
c - s ) ) == NULL )
{
return( POLARSSL_ERR_X509WRITE_MALLOC_FAILED );
}
while( c < end && *(c + 1) == ' ' )
c++;
s = c + 1;
in_tag = 1;
}
c++;
}
exit:
return( ret );
}
#if defined(POLARSSL_RSA_C)
/*
* RSAPublicKey ::= SEQUENCE {
* modulus INTEGER, -- n
* publicExponent INTEGER -- e
* }
*/
static int x509_write_rsa_pubkey( unsigned char **p, unsigned char *start,
rsa_context *rsa )
{
int ret;
size_t len = 0;
ASN1_CHK_ADD( len, asn1_write_mpi( p, start, &rsa->E ) );
ASN1_CHK_ADD( len, asn1_write_mpi( p, start, &rsa->N ) );
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
return( len );
}
#endif /* POLARSSL_RSA_C */
#if defined(POLARSSL_ECP_C)
/*
* EC public key is an EC point
*/
static int x509_write_ec_pubkey( unsigned char **p, unsigned char *start,
ecp_keypair *ec )
{
int ret;
size_t len = 0;
unsigned char buf[POLARSSL_ECP_MAX_PT_LEN];
if( ( ret = ecp_point_write_binary( &ec->grp, &ec->Q,
POLARSSL_ECP_PF_UNCOMPRESSED,
&len, buf, sizeof( buf ) ) ) != 0 )
{
return( ret );
}
if( *p - start < (int) len )
return( POLARSSL_ERR_ASN1_BUF_TOO_SMALL );
*p -= len;
memcpy( *p, buf, len );
return( len );
}
/*
* ECParameters ::= CHOICE {
* namedCurve OBJECT IDENTIFIER
* }
*/
static int x509_write_ec_param( unsigned char **p, unsigned char *start,
ecp_keypair *ec )
{
int ret;
size_t len = 0;
const char *oid;
size_t oid_len;
if( ( ret = oid_get_oid_by_ec_grp( ec->grp.id, &oid, &oid_len ) ) != 0 )
return( ret );
ASN1_CHK_ADD( len, asn1_write_oid( p, start, oid, oid_len ) );
return( len );
}
#endif /* POLARSSL_ECP_C */
static int x509_write_pubkey( unsigned char **p, unsigned char *start,
const pk_context *key )
{
int ret;
size_t len = 0;
#if defined(POLARSSL_RSA_C)
if( pk_get_type( key ) == POLARSSL_PK_RSA )
ASN1_CHK_ADD( len, x509_write_rsa_pubkey( p, start, pk_rsa( *key ) ) );
else
#endif
#if defined(POLARSSL_ECP_C)
if( pk_get_type( key ) == POLARSSL_PK_ECKEY )
ASN1_CHK_ADD( len, x509_write_ec_pubkey( p, start, pk_ec( *key ) ) );
else
#endif
return( POLARSSL_ERR_X509_FEATURE_UNAVAILABLE );
return( len );
}
void x509write_csr_init( x509write_csr *ctx )
{
memset( ctx, 0, sizeof(x509write_csr) );
}
void x509write_csr_free( x509write_csr *ctx )
{
asn1_free_named_data_list( &ctx->subject );
asn1_free_named_data_list( &ctx->extensions );
memset( ctx, 0, sizeof(x509write_csr) );
}
void x509write_csr_set_md_alg( x509write_csr *ctx, md_type_t md_alg )
{
ctx->md_alg = md_alg;
}
void x509write_csr_set_key( x509write_csr *ctx, pk_context *key )
{
ctx->key = key;
}
int x509write_csr_set_subject_name( x509write_csr *ctx, char *subject_name )
{
return x509write_string_to_names( &ctx->subject, subject_name );
}
/* The first byte of the value in the asn1_named_data structure is reserved
* to store the critical boolean for us
*/
static int x509_set_extension( asn1_named_data **head,
const char *oid, size_t oid_len,
int critical,
const unsigned char *val, size_t val_len )
{
asn1_named_data *cur;
if( ( cur = asn1_store_named_data( head, oid, oid_len,
NULL, val_len + 1 ) ) == NULL )
{
return( POLARSSL_ERR_X509WRITE_MALLOC_FAILED );
}
cur->val.p[0] = critical;
memcpy( cur->val.p + 1, val, val_len );
return( 0 );
}
int x509write_csr_set_extension( x509write_csr *ctx,
const char *oid, size_t oid_len,
const unsigned char *val, size_t val_len )
{
return x509_set_extension( &ctx->extensions, oid, oid_len,
0, val, val_len );
}
int x509write_csr_set_key_usage( x509write_csr *ctx, unsigned char key_usage )
{
unsigned char buf[4];
unsigned char *c;
int ret;
c = buf + 4;
if( ( ret = asn1_write_bitstring( &c, buf, &key_usage, 7 ) ) != 4 )
return( ret );
ret = x509write_csr_set_extension( ctx, OID_KEY_USAGE,
OID_SIZE( OID_KEY_USAGE ),
buf, 4 );
if( ret != 0 )
return( ret );
return( 0 );
}
int x509write_csr_set_ns_cert_type( x509write_csr *ctx,
unsigned char ns_cert_type )
{
unsigned char buf[4];
unsigned char *c;
int ret;
c = buf + 4;
if( ( ret = asn1_write_bitstring( &c, buf, &ns_cert_type, 8 ) ) != 4 )
return( ret );
ret = x509write_csr_set_extension( ctx, OID_NS_CERT_TYPE,
OID_SIZE( OID_NS_CERT_TYPE ),
buf, 4 );
if( ret != 0 )
return( ret );
return( 0 );
}
void x509write_crt_init( x509write_cert *ctx )
{
memset( ctx, 0, sizeof(x509write_cert) );
mpi_init( &ctx->serial );
ctx->version = X509_CRT_VERSION_3;
}
void x509write_crt_free( x509write_cert *ctx )
{
mpi_free( &ctx->serial );
asn1_free_named_data_list( &ctx->subject );
asn1_free_named_data_list( &ctx->issuer );
asn1_free_named_data_list( &ctx->extensions );
memset( ctx, 0, sizeof(x509write_csr) );
}
void x509write_crt_set_md_alg( x509write_cert *ctx, md_type_t md_alg )
{
ctx->md_alg = md_alg;
}
void x509write_crt_set_subject_key( x509write_cert *ctx, pk_context *key )
{
ctx->subject_key = key;
}
void x509write_crt_set_issuer_key( x509write_cert *ctx, pk_context *key )
{
ctx->issuer_key = key;
}
int x509write_crt_set_subject_name( x509write_cert *ctx, char *subject_name )
{
return x509write_string_to_names( &ctx->subject, subject_name );
}
int x509write_crt_set_issuer_name( x509write_cert *ctx, char *issuer_name )
{
return x509write_string_to_names( &ctx->issuer, issuer_name );
}
int x509write_crt_set_serial( x509write_cert *ctx, const mpi *serial )
{
int ret;
if( ( ret = mpi_copy( &ctx->serial, serial ) ) != 0 )
return( ret );
return( 0 );
}
int x509write_crt_set_validity( x509write_cert *ctx, char *not_before,
char *not_after )
{
if( strlen(not_before) != X509_RFC5280_UTC_TIME_LEN - 1 ||
strlen(not_after) != X509_RFC5280_UTC_TIME_LEN - 1 )
{
return( POLARSSL_ERR_X509WRITE_BAD_INPUT_DATA );
}
strncpy( ctx->not_before, not_before, X509_RFC5280_UTC_TIME_LEN );
strncpy( ctx->not_after , not_after , X509_RFC5280_UTC_TIME_LEN );
ctx->not_before[X509_RFC5280_UTC_TIME_LEN - 1] = 'Z';
ctx->not_after[X509_RFC5280_UTC_TIME_LEN - 1] = 'Z';
return( 0 );
}
int x509write_crt_set_extension( x509write_cert *ctx,
const char *oid, size_t oid_len,
int critical,
const unsigned char *val, size_t val_len )
{
return x509_set_extension( &ctx->extensions, oid, oid_len,
critical, val, val_len );
}
int x509write_crt_set_basic_constraints( x509write_cert *ctx,
int is_ca, int max_pathlen )
{
int ret;
unsigned char buf[9];
unsigned char *c = buf + sizeof(buf);
size_t len = 0;
memset( buf, 0, sizeof(buf) );
if( is_ca && max_pathlen > 127 )
return( POLARSSL_ERR_X509WRITE_BAD_INPUT_DATA );
if( is_ca )
{
if( max_pathlen >= 0 )
{
ASN1_CHK_ADD( len, asn1_write_int( &c, buf, max_pathlen ) );
}
ASN1_CHK_ADD( len, asn1_write_bool( &c, buf, 1 ) );
}
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
return x509write_crt_set_extension( ctx, OID_BASIC_CONSTRAINTS,
OID_SIZE( OID_BASIC_CONSTRAINTS ),
0, buf + sizeof(buf) - len, len );
}
int x509write_crt_set_subject_key_identifier( x509write_cert *ctx )
{
int ret;
unsigned char buf[POLARSSL_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */
unsigned char *c = buf + sizeof(buf);
size_t len = 0;
memset( buf, 0, sizeof(buf));
ASN1_CHK_ADD( len, x509_write_pubkey( &c, buf, ctx->subject_key ) );
sha1( buf + sizeof(buf) - len, len, buf + sizeof(buf) - 20 );
c = buf + sizeof(buf) - 20;
len = 20;
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_OCTET_STRING ) );
return x509write_crt_set_extension( ctx, OID_SUBJECT_KEY_IDENTIFIER,
OID_SIZE( OID_SUBJECT_KEY_IDENTIFIER ),
0, buf + sizeof(buf) - len, len );
}
int x509write_crt_set_authority_key_identifier( x509write_cert *ctx )
{
int ret;
unsigned char buf[POLARSSL_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */
unsigned char *c = buf + sizeof(buf);
size_t len = 0;
memset( buf, 0, sizeof(buf));
ASN1_CHK_ADD( len, x509_write_pubkey( &c, buf, ctx->issuer_key ) );
sha1( buf + sizeof(buf) - len, len, buf + sizeof(buf) - 20 );
c = buf + sizeof(buf) - 20;
len = 20;
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONTEXT_SPECIFIC | 0 ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
return x509write_crt_set_extension( ctx, OID_AUTHORITY_KEY_IDENTIFIER,
OID_SIZE( OID_AUTHORITY_KEY_IDENTIFIER ),
0, buf + sizeof(buf) - len, len );
}
int x509write_crt_set_key_usage( x509write_cert *ctx, unsigned char key_usage )
{
unsigned char buf[4];
unsigned char *c;
int ret;
c = buf + 4;
if( ( ret = asn1_write_bitstring( &c, buf, &key_usage, 7 ) ) != 4 )
return( ret );
ret = x509write_crt_set_extension( ctx, OID_KEY_USAGE,
OID_SIZE( OID_KEY_USAGE ),
1, buf, 4 );
if( ret != 0 )
return( ret );
return( 0 );
}
int x509write_crt_set_ns_cert_type( x509write_cert *ctx,
unsigned char ns_cert_type )
{
unsigned char buf[4];
unsigned char *c;
int ret;
c = buf + 4;
if( ( ret = asn1_write_bitstring( &c, buf, &ns_cert_type, 8 ) ) != 4 )
return( ret );
ret = x509write_crt_set_extension( ctx, OID_NS_CERT_TYPE,
OID_SIZE( OID_NS_CERT_TYPE ),
0, buf, 4 );
if( ret != 0 )
return( ret );
return( 0 );
}
int x509write_pubkey_der( pk_context *key, unsigned char *buf, size_t size )
{
int ret;
unsigned char *c;
size_t len = 0, par_len = 0, oid_len;
const char *oid;
c = buf + size;
ASN1_CHK_ADD( len, x509_write_pubkey( &c, buf, key ) );
if( c - buf < 1 )
return( POLARSSL_ERR_ASN1_BUF_TOO_SMALL );
/*
* SubjectPublicKeyInfo ::= SEQUENCE {
* algorithm AlgorithmIdentifier,
* subjectPublicKey BIT STRING }
*/
*--c = 0;
len += 1;
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_BIT_STRING ) );
if( ( ret = oid_get_oid_by_pk_alg( pk_get_type( key ),
&oid, &oid_len ) ) != 0 )
{
return( ret );
}
#if defined(POLARSSL_ECP_C)
if( pk_get_type( key ) == POLARSSL_PK_ECKEY )
{
ASN1_CHK_ADD( par_len, x509_write_ec_param( &c, buf, pk_ec( *key ) ) );
}
#endif
ASN1_CHK_ADD( len, asn1_write_algorithm_identifier( &c, buf, oid, oid_len,
par_len ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
return( len );
}
int x509write_key_der( pk_context *key, unsigned char *buf, size_t size )
{
int ret;
unsigned char *c = buf + size;
size_t len = 0;
#if defined(POLARSSL_RSA_C)
if( pk_get_type( key ) == POLARSSL_PK_RSA )
{
rsa_context *rsa = pk_rsa( *key );
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->QP ) );
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->DQ ) );
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->DP ) );
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->Q ) );
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->P ) );
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->D ) );
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->E ) );
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->N ) );
ASN1_CHK_ADD( len, asn1_write_int( &c, buf, 0 ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
}
else
#endif
#if defined(POLARSSL_ECP_C)
if( pk_get_type( key ) == POLARSSL_PK_ECKEY )
{
ecp_keypair *ec = pk_ec( *key );
size_t pub_len = 0, par_len = 0;
/*
* RFC 5915, or SEC1 Appendix C.4
*
* ECPrivateKey ::= SEQUENCE {
* version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
* privateKey OCTET STRING,
* parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
* publicKey [1] BIT STRING OPTIONAL
* }
*/
/* publicKey */
ASN1_CHK_ADD( pub_len, x509_write_ec_pubkey( &c, buf, ec ) );
if( c - buf < 1 )
return( POLARSSL_ERR_ASN1_BUF_TOO_SMALL );
*--c = 0;
pub_len += 1;
ASN1_CHK_ADD( pub_len, asn1_write_len( &c, buf, pub_len ) );
ASN1_CHK_ADD( pub_len, asn1_write_tag( &c, buf, ASN1_BIT_STRING ) );
ASN1_CHK_ADD( pub_len, asn1_write_len( &c, buf, pub_len ) );
ASN1_CHK_ADD( pub_len, asn1_write_tag( &c, buf,
ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 1 ) );
len += pub_len;
/* parameters */
ASN1_CHK_ADD( par_len, x509_write_ec_param( &c, buf, ec ) );
ASN1_CHK_ADD( par_len, asn1_write_len( &c, buf, par_len ) );
ASN1_CHK_ADD( par_len, asn1_write_tag( &c, buf,
ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 0 ) );
len += par_len;
/* privateKey: write as MPI then fix tag */
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &ec->d ) );
*c = ASN1_OCTET_STRING;
/* version */
ASN1_CHK_ADD( len, asn1_write_int( &c, buf, 1 ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
}
else
#endif
return( POLARSSL_ERR_X509_FEATURE_UNAVAILABLE );
return( len );
}
/*
* 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,
const char *oid, size_t oid_len,
const unsigned char *name, size_t name_len )
{
int ret;
size_t len = 0;
// Write PrintableString for all except OID_PKCS9_EMAIL
//
if( OID_SIZE( OID_PKCS9_EMAIL ) == oid_len &&
memcmp( oid, OID_PKCS9_EMAIL, oid_len ) == 0 )
{
ASN1_CHK_ADD( len, asn1_write_ia5_string( p, start,
(const char *) name,
name_len ) );
}
else
{
ASN1_CHK_ADD( len, asn1_write_printable_string( p, start,
(const char *) name,
name_len ) );
}
// Write OID
//
ASN1_CHK_ADD( len, asn1_write_oid( p, start, oid, oid_len ) );
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_CONSTRUCTED | ASN1_SET ) );
return( len );
}
static int x509_write_names( unsigned char **p, unsigned char *start,
asn1_named_data *first )
{
int ret;
size_t len = 0;
asn1_named_data *cur = first;
while( cur != NULL )
{
ASN1_CHK_ADD( len, x509_write_name( p, start, (char *) cur->oid.p,
cur->oid.len,
cur->val.p, cur->val.len ) );
cur = cur->next;
}
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
return( len );
}
static int x509_write_sig( unsigned char **p, unsigned char *start,
const char *oid, size_t oid_len,
unsigned char *sig, size_t size )
{
int ret;
size_t len = 0;
if( *p - start < (int) size + 1 )
return( POLARSSL_ERR_ASN1_BUF_TOO_SMALL );
len = size;
(*p) -= len;
memcpy( *p, sig, len );
*--(*p) = 0;
len += 1;
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_BIT_STRING ) );
// Write OID
//
ASN1_CHK_ADD( len, asn1_write_algorithm_identifier( p, start, oid,
oid_len, 0 ) );
return( len );
}
static int x509_write_time( unsigned char **p, unsigned char *start,
const char *time, size_t size )
{
int ret;
size_t len = 0;
/*
* write ASN1_UTC_TIME if year < 2050 (2 bytes shorter)
*/
if( time[0] == '2' && time[1] == '0' && time [2] < '5' )
{
ASN1_CHK_ADD( len, asn1_write_raw_buffer( p, start,
(const unsigned char *) time + 2,
size - 2 ) );
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_UTC_TIME ) );
}
else
{
ASN1_CHK_ADD( len, asn1_write_raw_buffer( p, start,
(const unsigned char *) time,
size ) );
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_GENERALIZED_TIME ) );
}
return( len );
}
static int x509_write_extension( unsigned char **p, unsigned char *start,
asn1_named_data *ext )
{
int ret;
size_t len = 0;
ASN1_CHK_ADD( len, asn1_write_raw_buffer( p, start, ext->val.p + 1,
ext->val.len - 1 ) );
ASN1_CHK_ADD( len, asn1_write_len( p, start, ext->val.len - 1 ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_OCTET_STRING ) );
if( ext->val.p[0] != 0 )
{
ASN1_CHK_ADD( len, asn1_write_bool( p, start, 1 ) );
}
ASN1_CHK_ADD( len, asn1_write_raw_buffer( p, start, ext->oid.p,
ext->oid.len ) );
ASN1_CHK_ADD( len, asn1_write_len( p, start, ext->oid.len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_OID ) );
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
return( 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
* }
*/
static int x509_write_extensions( unsigned char **p, unsigned char *start,
asn1_named_data *first )
{
int ret;
size_t len = 0;
asn1_named_data *cur_ext = first;
while( cur_ext != NULL )
{
ASN1_CHK_ADD( len, x509_write_extension( p, start, cur_ext ) );
cur_ext = cur_ext->next;
}
return( len );
}
int x509write_csr_der( x509write_csr *ctx, unsigned char *buf, size_t size,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
const char *sig_oid;
size_t sig_oid_len = 0;
unsigned char *c, *c2;
unsigned char hash[64];
unsigned char sig[POLARSSL_MPI_MAX_SIZE];
unsigned char tmp_buf[2048];
size_t pub_len = 0, sig_and_oid_len = 0, sig_len;
size_t len = 0;
pk_type_t pk_alg;
/*
* Prepare data to be signed in tmp_buf
*/
c = tmp_buf + sizeof( tmp_buf );
ASN1_CHK_ADD( len, x509_write_extensions( &c, tmp_buf, ctx->extensions ) );
if( len )
{
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SET ) );
ASN1_CHK_ADD( len, asn1_write_oid( &c, tmp_buf, OID_PKCS9_CSR_EXT_REQ,
OID_SIZE( OID_PKCS9_CSR_EXT_REQ ) ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
}
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_CONTEXT_SPECIFIC ) );
ASN1_CHK_ADD( pub_len, x509write_pubkey_der( ctx->key,
tmp_buf, c - tmp_buf ) );
c -= pub_len;
len += pub_len;
/*
* Subject ::= Name
*/
ASN1_CHK_ADD( len, x509_write_names( &c, tmp_buf, ctx->subject ) );
/*
* Version ::= INTEGER { v1(0), v2(1), v3(2) }
*/
ASN1_CHK_ADD( len, asn1_write_int( &c, tmp_buf, 0 ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
/*
* Prepare signature
*/
md( md_info_from_type( ctx->md_alg ), c, len, hash );
pk_alg = pk_get_type( ctx->key );
if( pk_alg == POLARSSL_PK_ECKEY )
pk_alg = POLARSSL_PK_ECDSA;
if( ( ret = pk_sign( ctx->key, ctx->md_alg, hash, 0, sig, &sig_len,
f_rng, p_rng ) ) != 0 ||
( ret = oid_get_oid_by_sig_alg( pk_alg, ctx->md_alg,
&sig_oid, &sig_oid_len ) ) != 0 )
{
return( ret );
}
/*
* Write data to output buffer
*/
c2 = buf + size;
ASN1_CHK_ADD( sig_and_oid_len, x509_write_sig( &c2, buf,
sig_oid, sig_oid_len, sig, sig_len ) );
c2 -= len;
memcpy( c2, c, len );
len += sig_and_oid_len;
ASN1_CHK_ADD( len, asn1_write_len( &c2, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c2, buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
return( len );
}
int x509write_crt_der( x509write_cert *ctx, unsigned char *buf, size_t size,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
const char *sig_oid;
size_t sig_oid_len = 0;
unsigned char *c, *c2;
unsigned char hash[64];
unsigned char sig[POLARSSL_MPI_MAX_SIZE];
unsigned char tmp_buf[2048];
size_t sub_len = 0, pub_len = 0, sig_and_oid_len = 0, sig_len;
size_t len = 0;
pk_type_t pk_alg;
/*
* Prepare data to be signed in tmp_buf
*/
c = tmp_buf + sizeof( tmp_buf );
/* Signature algorithm needed in TBS, and later for actual signature */
pk_alg = pk_get_type( ctx->issuer_key );
if( pk_alg == POLARSSL_PK_ECKEY )
pk_alg = POLARSSL_PK_ECDSA;
if( ( ret = oid_get_oid_by_sig_alg( pk_alg, ctx->md_alg,
&sig_oid, &sig_oid_len ) ) != 0 )
{
return( ret );
}
/*
* Extensions ::= SEQUENCE SIZE (1..MAX) OF Extension
*/
ASN1_CHK_ADD( len, x509_write_extensions( &c, tmp_buf, ctx->extensions ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 3 ) );
/*
* SubjectPublicKeyInfo
*/
ASN1_CHK_ADD( pub_len, x509write_pubkey_der( ctx->subject_key,
tmp_buf, c - tmp_buf ) );
c -= pub_len;
len += pub_len;
/*
* Subject ::= Name
*/
ASN1_CHK_ADD( len, x509_write_names( &c, tmp_buf, ctx->subject ) );
/*
* Validity ::= SEQUENCE {
* notBefore Time,
* notAfter Time }
*/
sub_len = 0;
ASN1_CHK_ADD( sub_len, x509_write_time( &c, tmp_buf, ctx->not_after,
X509_RFC5280_UTC_TIME_LEN ) );
ASN1_CHK_ADD( sub_len, x509_write_time( &c, tmp_buf, ctx->not_before,
X509_RFC5280_UTC_TIME_LEN ) );
len += sub_len;
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, sub_len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
/*
* Issuer ::= Name
*/
ASN1_CHK_ADD( len, x509_write_names( &c, tmp_buf, ctx->issuer ) );
/*
* Signature ::= AlgorithmIdentifier
*/
ASN1_CHK_ADD( len, asn1_write_algorithm_identifier( &c, tmp_buf,
sig_oid, strlen( sig_oid ), 0 ) );
/*
* Serial ::= INTEGER
*/
ASN1_CHK_ADD( len, asn1_write_mpi( &c, tmp_buf, &ctx->serial ) );
/*
* Version ::= INTEGER { v1(0), v2(1), v3(2) }
*/
sub_len = 0;
ASN1_CHK_ADD( sub_len, asn1_write_int( &c, tmp_buf, ctx->version ) );
len += sub_len;
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, sub_len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 0 ) );
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
/*
* Make signature
*/
md( md_info_from_type( ctx->md_alg ), c, len, hash );
if( ( ret = pk_sign( ctx->issuer_key, ctx->md_alg, hash, 0, sig, &sig_len,
f_rng, p_rng ) ) != 0 )
{
return( ret );
}
/*
* Write data to output buffer
*/
c2 = buf + size;
ASN1_CHK_ADD( sig_and_oid_len, x509_write_sig( &c2, buf,
sig_oid, sig_oid_len, sig, sig_len ) );
c2 -= len;
memcpy( c2, c, len );
len += sig_and_oid_len;
ASN1_CHK_ADD( len, asn1_write_len( &c2, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c2, buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
return( len );
}
#define PEM_BEGIN_CRT "-----BEGIN CERTIFICATE-----\n"
#define PEM_END_CRT "-----END CERTIFICATE-----\n"
#define PEM_BEGIN_CSR "-----BEGIN CERTIFICATE REQUEST-----\n"
#define PEM_END_CSR "-----END CERTIFICATE REQUEST-----\n"
#define PEM_BEGIN_PUBLIC_KEY "-----BEGIN PUBLIC KEY-----\n"
#define PEM_END_PUBLIC_KEY "-----END PUBLIC KEY-----\n"
#define PEM_BEGIN_PRIVATE_KEY_RSA "-----BEGIN RSA PRIVATE KEY-----\n"
#define PEM_END_PRIVATE_KEY_RSA "-----END RSA PRIVATE KEY-----\n"
#define PEM_BEGIN_PRIVATE_KEY_EC "-----BEGIN EC PRIVATE KEY-----\n"
#define PEM_END_PRIVATE_KEY_EC "-----END EC PRIVATE KEY-----\n"
#if defined(POLARSSL_BASE64_C)
static int x509write_pemify( const char *begin_str, const char *end_str,
const unsigned char *der_data, size_t der_len,
unsigned char *buf, size_t size )
{
int ret;
unsigned char base_buf[4096];
unsigned char *c = base_buf, *p = buf;
size_t len = 0, olen = sizeof(base_buf);
if( ( ret = base64_encode( base_buf, &olen, der_data, der_len ) ) != 0 )
return( ret );
if( olen + strlen( begin_str ) + strlen( end_str ) +
olen / 64 > size )
{
return( POLARSSL_ERR_BASE64_BUFFER_TOO_SMALL );
}
memcpy( p, begin_str, strlen( begin_str ) );
p += strlen( begin_str );
while( olen )
{
len = ( olen > 64 ) ? 64 : olen;
memcpy( p, c, len );
olen -= len;
p += len;
c += len;
*p++ = '\n';
}
memcpy( p, end_str, strlen( end_str ) );
p += strlen( end_str );
*p = '\0';
return( 0 );
}
int x509write_crt_pem( x509write_cert *crt, unsigned char *buf, size_t size,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
unsigned char output_buf[4096];
if( ( ret = x509write_crt_der( crt, output_buf, sizeof(output_buf),
f_rng, p_rng ) ) < 0 )
{
return( ret );
}
if( ( ret = x509write_pemify( PEM_BEGIN_CRT, PEM_END_CRT,
output_buf + sizeof(output_buf) - ret,
ret, buf, size ) ) != 0 )
{
return( ret );
}
return( 0 );
}
int x509write_pubkey_pem( pk_context *key, unsigned char *buf, size_t size )
{
int ret;
unsigned char output_buf[4096];
if( ( ret = x509write_pubkey_der( key, output_buf,
sizeof(output_buf) ) ) < 0 )
{
return( ret );
}
if( ( ret = x509write_pemify( PEM_BEGIN_PUBLIC_KEY, PEM_END_PUBLIC_KEY,
output_buf + sizeof(output_buf) - ret,
ret, buf, size ) ) != 0 )
{
return( ret );
}
return( 0 );
}
int x509write_key_pem( pk_context *key, unsigned char *buf, size_t size )
{
int ret;
unsigned char output_buf[4096];
char *begin, *end;
if( ( ret = x509write_key_der( key, output_buf,
sizeof(output_buf) ) ) < 0 )
{
return( ret );
}
#if defined(POLARSSL_RSA_C)
if( pk_get_type( key ) == POLARSSL_PK_RSA )
{
begin = PEM_BEGIN_PRIVATE_KEY_RSA;
end = PEM_END_PRIVATE_KEY_RSA;
}
else
#endif
#if defined(POLARSSL_ECP_C)
if( pk_get_type( key ) == POLARSSL_PK_ECKEY )
{
begin = PEM_BEGIN_PRIVATE_KEY_EC;
end = PEM_END_PRIVATE_KEY_EC;
}
else
#endif
return( POLARSSL_ERR_X509_FEATURE_UNAVAILABLE );
if( ( ret = x509write_pemify( begin, end,
output_buf + sizeof(output_buf) - ret,
ret, buf, size ) ) != 0 )
{
return( ret );
}
return( 0 );
}
int x509write_csr_pem( x509write_csr *ctx, unsigned char *buf, size_t size,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng )
{
int ret;
unsigned char output_buf[4096];
if( ( ret = x509write_csr_der( ctx, output_buf, sizeof(output_buf),
f_rng, p_rng ) ) < 0 )
{
return( ret );
}
if( ( ret = x509write_pemify( PEM_BEGIN_CSR, PEM_END_CSR,
output_buf + sizeof(output_buf) - ret,
ret, buf, size ) ) != 0 )
{
return( ret );
}
return( 0 );
}
#endif /* POLARSSL_BASE64_C */
#endif