mbedtls/library/x509write.c

638 lines
18 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.
*/
#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"
#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
void x509write_csr_init( x509_csr *ctx )
{
memset( ctx, 0, sizeof(x509_csr) );
}
void x509write_csr_free( x509_csr *ctx )
{
x509_req_name *cur;
asn1_named_data *cur_ext;
while( ( cur = ctx->subject ) != NULL )
{
ctx->subject = cur->next;
polarssl_free( cur );
}
while( ( cur_ext = ctx->extensions ) != NULL )
{
ctx->extensions = cur_ext->next;
asn1_free_named_data( cur_ext );
polarssl_free( cur_ext );
}
memset( ctx, 0, sizeof(x509_csr) );
}
void x509write_csr_set_md_alg( x509_csr *ctx, md_type_t md_alg )
{
ctx->md_alg = md_alg;
}
void x509write_csr_set_rsa_key( x509_csr *ctx, rsa_context *rsa )
{
ctx->rsa = rsa;
}
int x509write_csr_set_subject_name( x509_csr *ctx, char *subject_name )
{
int ret = 0;
char *s = subject_name, *c = s;
char *end = s + strlen( s );
char *oid = NULL;
int in_tag = 1;
x509_req_name *cur;
while( ctx->subject )
{
cur = ctx->subject;
ctx->subject = ctx->subject->next;
polarssl_free( cur );
}
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( c - s > 127 )
{
ret = POLARSSL_ERR_X509WRITE_BAD_INPUT_DATA;
goto exit;
}
cur = polarssl_malloc( sizeof(x509_req_name) );
if( cur == NULL )
{
ret = POLARSSL_ERR_X509WRITE_MALLOC_FAILED;
goto exit;
}
memset( cur, 0, sizeof(x509_req_name) );
cur->next = ctx->subject;
ctx->subject = cur;
strncpy( cur->oid, oid, strlen( oid ) );
strncpy( cur->name, s, c - s );
s = c + 1;
in_tag = 1;
}
c++;
}
exit:
return( ret );
}
int x509write_csr_set_extension( x509_csr *ctx,
const char *oid, size_t oid_len,
const unsigned char *val, size_t val_len )
{
asn1_named_data *cur;
if( ( cur = asn1_find_named_data( ctx->extensions, oid,
oid_len ) ) == NULL )
{
cur = polarssl_malloc( sizeof(asn1_named_data) );
if( cur == NULL )
return( POLARSSL_ERR_X509WRITE_MALLOC_FAILED );
memset( cur, 0, sizeof(asn1_named_data) );
cur->oid.len = oid_len;
cur->oid.p = polarssl_malloc( oid_len );
if( cur->oid.p == NULL )
{
polarssl_free( cur );
return( POLARSSL_ERR_X509WRITE_MALLOC_FAILED );
}
cur->val.len = val_len;
cur->val.p = polarssl_malloc( val_len );
if( cur->val.p == NULL )
{
polarssl_free( cur->oid.p );
polarssl_free( cur );
return( POLARSSL_ERR_X509WRITE_MALLOC_FAILED );
}
memcpy( cur->oid.p, oid, oid_len );
cur->next = ctx->extensions;
ctx->extensions = cur;
}
if( cur->val.len != val_len )
{
polarssl_free( cur->val.p );
cur->val.len = val_len;
cur->val.p = polarssl_malloc( val_len );
if( cur->val.p == NULL )
{
polarssl_free( cur->oid.p );
polarssl_free( cur );
return( POLARSSL_ERR_X509WRITE_MALLOC_FAILED );
}
}
memcpy( cur->val.p, val, val_len );
return( 0 );
}
int x509write_csr_set_key_usage( x509_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( x509_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 );
}
int x509write_pubkey_der( rsa_context *rsa, unsigned char *buf, size_t size )
{
int ret;
unsigned char *c;
size_t len = 0;
c = buf + size - 1;
/*
* RSAPublicKey ::= SEQUENCE {
* modulus INTEGER, -- n
* publicExponent INTEGER -- e
* }
*/
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_len( &c, buf, len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
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 ) );
ASN1_CHK_ADD( len, asn1_write_algorithm_identifier( &c, buf, OID_PKCS1_RSA ) );
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( rsa_context *rsa, unsigned char *buf, size_t size )
{
int ret;
unsigned char *c;
size_t len = 0;
c = buf + size - 1;
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 ) );
// TODO: Make NON RSA Specific variant later on
/* *--c = 0;
len += 1;
len += asn1_write_len( &c, len);
len += asn1_write_tag( &c, ASN1_BIT_STRING );
len += asn1_write_oid( &c, OID_PKCS1_RSA );
len += asn1_write_int( &c, 0 );
len += asn1_write_len( &c, len);
len += asn1_write_tag( &c, ASN1_CONSTRUCTED | ASN1_SEQUENCE );*/
/* for(i = 0; i < len; ++i)
{
if (i % 16 == 0 ) printf("\n");
printf("%02x ", c[i]);
}
printf("\n");*/
return( len );
}
static int x509_write_name( unsigned char **p, unsigned char *start, char *oid,
char *name )
{
int ret;
size_t string_len = 0;
size_t oid_len = 0;
size_t len = 0;
// Write PrintableString for all except OID_PKCS9_EMAIL
//
if( OID_SIZE( OID_PKCS9_EMAIL ) == strlen( oid ) &&
memcmp( oid, OID_PKCS9_EMAIL, strlen( oid ) ) == 0 )
{
ASN1_CHK_ADD( string_len, asn1_write_ia5_string( p, start, name ) );
}
else
ASN1_CHK_ADD( string_len, asn1_write_printable_string( p, start, name ) );
// Write OID
//
ASN1_CHK_ADD( oid_len, asn1_write_oid( p, start, oid ) );
len = oid_len + string_len;
ASN1_CHK_ADD( len, asn1_write_len( p, start, oid_len + string_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_sig( unsigned char **p, unsigned char *start,
const char *oid, 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 ) );
return( len );
}
int x509write_csr_der( x509_csr *ctx, unsigned char *buf, size_t size )
{
int ret;
const char *sig_oid;
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_len = 0;
size_t len = 0;
x509_req_name *cur = ctx->subject;
asn1_named_data *cur_ext = ctx->extensions;
c = tmp_buf + 2048 - 1;
while( cur_ext != NULL )
{
size_t ext_len = 0;
ASN1_CHK_ADD( ext_len, asn1_write_raw_buffer( &c, tmp_buf, cur_ext->val.p,
cur_ext->val.len ) );
ASN1_CHK_ADD( ext_len, asn1_write_len( &c, tmp_buf, cur_ext->val.len ) );
ASN1_CHK_ADD( ext_len, asn1_write_tag( &c, tmp_buf, ASN1_OCTET_STRING ) );
ASN1_CHK_ADD( ext_len, asn1_write_raw_buffer( &c, tmp_buf, cur_ext->oid.p,
cur_ext->oid.len ) );
ASN1_CHK_ADD( ext_len, asn1_write_len( &c, tmp_buf, cur_ext->oid.len ) );
ASN1_CHK_ADD( ext_len, asn1_write_tag( &c, tmp_buf, ASN1_OID ) );
ASN1_CHK_ADD( ext_len, asn1_write_len( &c, tmp_buf, ext_len ) );
ASN1_CHK_ADD( ext_len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
cur_ext = cur_ext->next;
len += ext_len;
}
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 ) );
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, asn1_write_mpi( &c, tmp_buf, &ctx->rsa->E ) );
ASN1_CHK_ADD( pub_len, asn1_write_mpi( &c, tmp_buf, &ctx->rsa->N ) );
ASN1_CHK_ADD( pub_len, asn1_write_len( &c, tmp_buf, pub_len ) );
ASN1_CHK_ADD( pub_len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
if( c - tmp_buf < 1 )
return( POLARSSL_ERR_ASN1_BUF_TOO_SMALL );
/*
* AlgorithmIdentifier ::= SEQUENCE {
* algorithm OBJECT IDENTIFIER,
* parameters ANY DEFINED BY algorithm OPTIONAL }
*/
*--c = 0;
pub_len += 1;
ASN1_CHK_ADD( pub_len, asn1_write_len( &c, tmp_buf, pub_len ) );
ASN1_CHK_ADD( pub_len, asn1_write_tag( &c, tmp_buf, ASN1_BIT_STRING ) );
ASN1_CHK_ADD( pub_len, asn1_write_algorithm_identifier( &c, tmp_buf, OID_PKCS1_RSA ) );
len += pub_len;
ASN1_CHK_ADD( len, asn1_write_len( &c, tmp_buf, pub_len ) );
ASN1_CHK_ADD( len, asn1_write_tag( &c, tmp_buf, ASN1_CONSTRUCTED | ASN1_SEQUENCE ) );
while( cur != NULL )
{
ASN1_CHK_ADD( sub_len, x509_write_name( &c, tmp_buf, cur->oid, cur->name ) );
cur = cur->next;
}
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 ) );
/*
* 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 ) );
md( md_info_from_type( ctx->md_alg ), c, len, hash );
rsa_pkcs1_sign( ctx->rsa, NULL, NULL, RSA_PRIVATE, ctx->md_alg, 0, hash, sig );
// Generate correct OID
//
ret = oid_get_oid_by_sig_alg( POLARSSL_PK_RSA, ctx->md_alg, &sig_oid );
c2 = buf + size - 1;
ASN1_CHK_ADD( sig_len, x509_write_sig( &c2, buf, sig_oid, sig, ctx->rsa->len ) );
c2 -= len;
memcpy( c2, c, len );
len += sig_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_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 "-----BEGIN RSA PRIVATE KEY-----\n"
#define PEM_END_PRIVATE_KEY "-----END RSA 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_pubkey_pem( rsa_context *rsa, unsigned char *buf, size_t size )
{
int ret;
unsigned char output_buf[4096];
if( ( ret = x509write_pubkey_der( rsa, 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) - 1 - ret,
ret, buf, size ) ) != 0 )
{
return( ret );
}
return( 0 );
}
int x509write_key_pem( rsa_context *rsa, unsigned char *buf, size_t size )
{
int ret;
unsigned char output_buf[4096];
if( ( ret = x509write_key_der( rsa, output_buf,
sizeof(output_buf) ) ) < 0 )
{
return( ret );
}
if( ( ret = x509write_pemify( PEM_BEGIN_PRIVATE_KEY, PEM_END_PRIVATE_KEY,
output_buf + sizeof(output_buf) - 1 - ret,
ret, buf, size ) ) != 0 )
{
return( ret );
}
return( 0 );
}
int x509write_csr_pem( x509_csr *ctx, unsigned char *buf, size_t size )
{
int ret;
unsigned char output_buf[4096];
if( ( ret = x509write_csr_der( ctx, output_buf,
sizeof(output_buf) ) ) < 0 )
{
return( ret );
}
if( ( ret = x509write_pemify( PEM_BEGIN_CSR, PEM_END_CSR,
output_buf + sizeof(output_buf) - 1 - ret,
ret, buf, size ) ) != 0 )
{
return( ret );
}
return( 0 );
}
#endif /* POLARSSL_BASE64_C */
#endif