sandbox
mbedtls ported to mbed-classic
Fork of
mbedtls
by 
Christopher Haster
Diff: source/x509write_crt.c
- Revision:
- 1:24750b9ad5ef
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/source/x509write_crt.c Fri Jan 22 16:44:49 2016 -0600
@@ -0,0 +1,456 @@
+/*
+ * X.509 certificate writing
+ *
+ * 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)
+ */
+/*
+ * References:
+ * - certificates: RFC 5280, updated by RFC 6818
+ * - CSRs: PKCS#10 v1.7 aka RFC 2986
+ * - attributes: PKCS#9 v2.0 aka RFC 2985
+ */
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#if defined(MBEDTLS_X509_CRT_WRITE_C)
+
+#include "mbedtls/x509_crt.h"
+#include "mbedtls/oid.h"
+#include "mbedtls/asn1write.h"
+#include "mbedtls/sha1.h"
+
+#include <string.h>
+
+#if defined(MBEDTLS_PEM_WRITE_C)
+#include "mbedtls/pem.h"
+#endif /* MBEDTLS_PEM_WRITE_C */
+
+/* Implementation that should never be optimized out by the compiler */
+static void mbedtls_zeroize( void *v, size_t n ) {
+ volatile unsigned char *p = v; while( n-- ) *p++ = 0;
+}
+
+void mbedtls_x509write_crt_init( mbedtls_x509write_cert *ctx )
+{
+ memset( ctx, 0, sizeof(mbedtls_x509write_cert) );
+
+ mbedtls_mpi_init( &ctx->serial );
+ ctx->version = MBEDTLS_X509_CRT_VERSION_3;
+}
+
+void mbedtls_x509write_crt_free( mbedtls_x509write_cert *ctx )
+{
+ mbedtls_mpi_free( &ctx->serial );
+
+ mbedtls_asn1_free_named_data_list( &ctx->subject );
+ mbedtls_asn1_free_named_data_list( &ctx->issuer );
+ mbedtls_asn1_free_named_data_list( &ctx->extensions );
+
+ mbedtls_zeroize( ctx, sizeof(mbedtls_x509write_cert) );
+}
+
+void mbedtls_x509write_crt_set_version( mbedtls_x509write_cert *ctx, int version )
+{
+ ctx->version = version;
+}
+
+void mbedtls_x509write_crt_set_md_alg( mbedtls_x509write_cert *ctx, mbedtls_md_type_t md_alg )
+{
+ ctx->md_alg = md_alg;
+}
+
+void mbedtls_x509write_crt_set_subject_key( mbedtls_x509write_cert *ctx, mbedtls_pk_context *key )
+{
+ ctx->subject_key = key;
+}
+
+void mbedtls_x509write_crt_set_issuer_key( mbedtls_x509write_cert *ctx, mbedtls_pk_context *key )
+{
+ ctx->issuer_key = key;
+}
+
+int mbedtls_x509write_crt_set_subject_name( mbedtls_x509write_cert *ctx,
+ const char *subject_name )
+{
+ return mbedtls_x509_string_to_names( &ctx->subject, subject_name );
+}
+
+int mbedtls_x509write_crt_set_issuer_name( mbedtls_x509write_cert *ctx,
+ const char *issuer_name )
+{
+ return mbedtls_x509_string_to_names( &ctx->issuer, issuer_name );
+}
+
+int mbedtls_x509write_crt_set_serial( mbedtls_x509write_cert *ctx, const mbedtls_mpi *serial )
+{
+ int ret;
+
+ if( ( ret = mbedtls_mpi_copy( &ctx->serial, serial ) ) != 0 )
+ return( ret );
+
+ return( 0 );
+}
+
+int mbedtls_x509write_crt_set_validity( mbedtls_x509write_cert *ctx, const char *not_before,
+ const char *not_after )
+{
+ if( strlen( not_before ) != MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1 ||
+ strlen( not_after ) != MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1 )
+ {
+ return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+ }
+ strncpy( ctx->not_before, not_before, MBEDTLS_X509_RFC5280_UTC_TIME_LEN );
+ strncpy( ctx->not_after , not_after , MBEDTLS_X509_RFC5280_UTC_TIME_LEN );
+ ctx->not_before[MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1] = 'Z';
+ ctx->not_after[MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1] = 'Z';
+
+ return( 0 );
+}
+
+int mbedtls_x509write_crt_set_extension( mbedtls_x509write_cert *ctx,
+ const char *oid, size_t oid_len,
+ int critical,
+ const unsigned char *val, size_t val_len )
+{
+ return mbedtls_x509_set_extension( &ctx->extensions, oid, oid_len,
+ critical, val, val_len );
+}
+
+int mbedtls_x509write_crt_set_basic_constraints( mbedtls_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( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+
+ if( is_ca )
+ {
+ if( max_pathlen >= 0 )
+ {
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_int( &c, buf, max_pathlen ) );
+ }
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_bool( &c, buf, 1 ) );
+ }
+
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_CONSTRUCTED |
+ MBEDTLS_ASN1_SEQUENCE ) );
+
+ return mbedtls_x509write_crt_set_extension( ctx, MBEDTLS_OID_BASIC_CONSTRAINTS,
+ MBEDTLS_OID_SIZE( MBEDTLS_OID_BASIC_CONSTRAINTS ),
+ 0, buf + sizeof(buf) - len, len );
+}
+
+#if defined(MBEDTLS_SHA1_C)
+int mbedtls_x509write_crt_set_subject_key_identifier( mbedtls_x509write_cert *ctx )
+{
+ int ret;
+ unsigned char buf[MBEDTLS_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */
+ unsigned char *c = buf + sizeof(buf);
+ size_t len = 0;
+
+ memset( buf, 0, sizeof(buf) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_pk_write_pubkey( &c, buf, ctx->subject_key ) );
+
+ mbedtls_sha1( buf + sizeof(buf) - len, len, buf + sizeof(buf) - 20 );
+ c = buf + sizeof(buf) - 20;
+ len = 20;
+
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_OCTET_STRING ) );
+
+ return mbedtls_x509write_crt_set_extension( ctx, MBEDTLS_OID_SUBJECT_KEY_IDENTIFIER,
+ MBEDTLS_OID_SIZE( MBEDTLS_OID_SUBJECT_KEY_IDENTIFIER ),
+ 0, buf + sizeof(buf) - len, len );
+}
+
+int mbedtls_x509write_crt_set_authority_key_identifier( mbedtls_x509write_cert *ctx )
+{
+ int ret;
+ unsigned char buf[MBEDTLS_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */
+ unsigned char *c = buf + sizeof(buf);
+ size_t len = 0;
+
+ memset( buf, 0, sizeof(buf) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_pk_write_pubkey( &c, buf, ctx->issuer_key ) );
+
+ mbedtls_sha1( buf + sizeof(buf) - len, len, buf + sizeof(buf) - 20 );
+ c = buf + sizeof(buf) - 20;
+ len = 20;
+
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_CONTEXT_SPECIFIC | 0 ) );
+
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_CONSTRUCTED |
+ MBEDTLS_ASN1_SEQUENCE ) );
+
+ return mbedtls_x509write_crt_set_extension( ctx, MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER,
+ MBEDTLS_OID_SIZE( MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER ),
+ 0, buf + sizeof(buf) - len, len );
+}
+#endif /* MBEDTLS_SHA1_C */
+
+int mbedtls_x509write_crt_set_key_usage( mbedtls_x509write_cert *ctx,
+ unsigned int key_usage )
+{
+ unsigned char buf[4], ku;
+ unsigned char *c;
+ int ret;
+
+ /* We currently only support 7 bits, from 0x80 to 0x02 */
+ if( ( key_usage & ~0xfe ) != 0 )
+ return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
+
+ c = buf + 4;
+ ku = (unsigned char) key_usage;
+
+ if( ( ret = mbedtls_asn1_write_bitstring( &c, buf, &ku, 7 ) ) != 4 )
+ return( ret );
+
+ ret = mbedtls_x509write_crt_set_extension( ctx, MBEDTLS_OID_KEY_USAGE,
+ MBEDTLS_OID_SIZE( MBEDTLS_OID_KEY_USAGE ),
+ 1, buf, 4 );
+ if( ret != 0 )
+ return( ret );
+
+ return( 0 );
+}
+
+int mbedtls_x509write_crt_set_ns_cert_type( mbedtls_x509write_cert *ctx,
+ unsigned char ns_cert_type )
+{
+ unsigned char buf[4];
+ unsigned char *c;
+ int ret;
+
+ c = buf + 4;
+
+ if( ( ret = mbedtls_asn1_write_bitstring( &c, buf, &ns_cert_type, 8 ) ) != 4 )
+ return( ret );
+
+ ret = mbedtls_x509write_crt_set_extension( ctx, MBEDTLS_OID_NS_CERT_TYPE,
+ MBEDTLS_OID_SIZE( MBEDTLS_OID_NS_CERT_TYPE ),
+ 0, buf, 4 );
+ if( ret != 0 )
+ return( ret );
+
+ return( 0 );
+}
+
+static int x509_write_time( unsigned char **p, unsigned char *start,
+ const char *time, size_t size )
+{
+ int ret;
+ size_t len = 0;
+
+ /*
+ * write MBEDTLS_ASN1_UTC_TIME if year < 2050 (2 bytes shorter)
+ */
+ if( time[0] == '2' && time[1] == '0' && time [2] < '5' )
+ {
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start,
+ (const unsigned char *) time + 2,
+ size - 2 ) );
+ 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_UTC_TIME ) );
+ }
+ else
+ {
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_raw_buffer( p, start,
+ (const unsigned char *) time,
+ size ) );
+ 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_GENERALIZED_TIME ) );
+ }
+
+ return( (int) len );
+}
+
+int mbedtls_x509write_crt_der( mbedtls_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[MBEDTLS_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;
+ mbedtls_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 = mbedtls_pk_get_type( ctx->issuer_key );
+ if( pk_alg == MBEDTLS_PK_ECKEY )
+ pk_alg = MBEDTLS_PK_ECDSA;
+
+ if( ( ret = mbedtls_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
+ */
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_x509_write_extensions( &c, tmp_buf, ctx->extensions ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
+ MBEDTLS_ASN1_SEQUENCE ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONTEXT_SPECIFIC |
+ MBEDTLS_ASN1_CONSTRUCTED | 3 ) );
+
+ /*
+ * SubjectPublicKeyInfo
+ */
+ MBEDTLS_ASN1_CHK_ADD( pub_len, mbedtls_pk_write_pubkey_der( ctx->subject_key,
+ tmp_buf, c - tmp_buf ) );
+ c -= pub_len;
+ len += pub_len;
+
+ /*
+ * Subject ::= Name
+ */
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_x509_write_names( &c, tmp_buf, ctx->subject ) );
+
+ /*
+ * Validity ::= SEQUENCE {
+ * notBefore Time,
+ * notAfter Time }
+ */
+ sub_len = 0;
+
+ MBEDTLS_ASN1_CHK_ADD( sub_len, x509_write_time( &c, tmp_buf, ctx->not_after,
+ MBEDTLS_X509_RFC5280_UTC_TIME_LEN ) );
+
+ MBEDTLS_ASN1_CHK_ADD( sub_len, x509_write_time( &c, tmp_buf, ctx->not_before,
+ MBEDTLS_X509_RFC5280_UTC_TIME_LEN ) );
+
+ len += sub_len;
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, sub_len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
+ MBEDTLS_ASN1_SEQUENCE ) );
+
+ /*
+ * Issuer ::= Name
+ */
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_x509_write_names( &c, tmp_buf, ctx->issuer ) );
+
+ /*
+ * Signature ::= AlgorithmIdentifier
+ */
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_algorithm_identifier( &c, tmp_buf,
+ sig_oid, strlen( sig_oid ), 0 ) );
+
+ /*
+ * Serial ::= INTEGER
+ */
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_mpi( &c, tmp_buf, &ctx->serial ) );
+
+ /*
+ * Version ::= INTEGER { v1(0), v2(1), v3(2) }
+ */
+ sub_len = 0;
+ MBEDTLS_ASN1_CHK_ADD( sub_len, mbedtls_asn1_write_int( &c, tmp_buf, ctx->version ) );
+ len += sub_len;
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, sub_len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONTEXT_SPECIFIC |
+ MBEDTLS_ASN1_CONSTRUCTED | 0 ) );
+
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
+ MBEDTLS_ASN1_SEQUENCE ) );
+
+ /*
+ * Make signature
+ */
+ mbedtls_md( mbedtls_md_info_from_type( ctx->md_alg ), c, len, hash );
+
+ if( ( ret = mbedtls_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;
+ MBEDTLS_ASN1_CHK_ADD( sig_and_oid_len, mbedtls_x509_write_sig( &c2, buf,
+ sig_oid, sig_oid_len, sig, sig_len ) );
+
+ c2 -= len;
+ memcpy( c2, c, len );
+
+ len += sig_and_oid_len;
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c2, buf, len ) );
+ MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c2, buf, MBEDTLS_ASN1_CONSTRUCTED |
+ MBEDTLS_ASN1_SEQUENCE ) );
+
+ return( (int) len );
+}
+
+#define PEM_BEGIN_CRT "-----BEGIN CERTIFICATE-----\n"
+#define PEM_END_CRT "-----END CERTIFICATE-----\n"
+
+#if defined(MBEDTLS_PEM_WRITE_C)
+int mbedtls_x509write_crt_pem( mbedtls_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];
+ size_t olen = 0;
+
+ if( ( ret = mbedtls_x509write_crt_der( crt, output_buf, sizeof(output_buf),
+ f_rng, p_rng ) ) < 0 )
+ {
+ return( ret );
+ }
+
+ if( ( ret = mbedtls_pem_write_buffer( PEM_BEGIN_CRT, PEM_END_CRT,
+ output_buf + sizeof(output_buf) - ret,
+ ret, buf, size, &olen ) ) != 0 )
+ {
+ return( ret );
+ }
+
+ return( 0 );
+}
+#endif /* MBEDTLS_PEM_WRITE_C */
+
+#endif /* MBEDTLS_X509_CRT_WRITE_C */