2 * X.509 Certificate Signing Request writing
4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5 * SPDX-License-Identifier: Apache-2.0
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
19 * This file is part of mbed TLS (https://tls.mbed.org)
23 * - CSRs: PKCS#10 v1.7 aka RFC 2986
24 * - attributes: PKCS#9 v2.0 aka RFC 2985
27 #if !defined(MBEDTLS_CONFIG_FILE)
28 #include "mbedtls/config.h"
30 #include MBEDTLS_CONFIG_FILE
33 #if defined(MBEDTLS_X509_CSR_WRITE_C)
35 #include "mbedtls/x509_csr.h"
36 #include "mbedtls/oid.h"
37 #include "mbedtls/asn1write.h"
38 #include "mbedtls/platform_util.h"
40 #if defined(MBEDTLS_USE_PSA_CRYPTO)
41 #include "psa/crypto.h"
42 #include "mbedtls/psa_util.h"
48 #if defined(MBEDTLS_PEM_WRITE_C)
49 #include "mbedtls/pem.h"
52 void mbedtls_x509write_csr_init( mbedtls_x509write_csr *ctx )
54 memset( ctx, 0, sizeof( mbedtls_x509write_csr ) );
57 void mbedtls_x509write_csr_free( mbedtls_x509write_csr *ctx )
59 mbedtls_asn1_free_named_data_list( &ctx->subject );
60 mbedtls_asn1_free_named_data_list( &ctx->extensions );
62 mbedtls_platform_zeroize( ctx, sizeof( mbedtls_x509write_csr ) );
65 void mbedtls_x509write_csr_set_md_alg( mbedtls_x509write_csr *ctx, mbedtls_md_type_t md_alg )
70 void mbedtls_x509write_csr_set_key( mbedtls_x509write_csr *ctx, mbedtls_pk_context *key )
75 int mbedtls_x509write_csr_set_subject_name( mbedtls_x509write_csr *ctx,
76 const char *subject_name )
78 return mbedtls_x509_string_to_names( &ctx->subject, subject_name );
81 int mbedtls_x509write_csr_set_extension( mbedtls_x509write_csr *ctx,
82 const char *oid, size_t oid_len,
83 const unsigned char *val, size_t val_len )
85 return mbedtls_x509_set_extension( &ctx->extensions, oid, oid_len,
89 int mbedtls_x509write_csr_set_key_usage( mbedtls_x509write_csr *ctx, unsigned char key_usage )
97 ret = mbedtls_asn1_write_named_bitstring( &c, buf, &key_usage, 8 );
98 if( ret < 3 || ret > 4 )
101 ret = mbedtls_x509write_csr_set_extension( ctx, MBEDTLS_OID_KEY_USAGE,
102 MBEDTLS_OID_SIZE( MBEDTLS_OID_KEY_USAGE ),
110 int mbedtls_x509write_csr_set_ns_cert_type( mbedtls_x509write_csr *ctx,
111 unsigned char ns_cert_type )
113 unsigned char buf[4];
119 ret = mbedtls_asn1_write_named_bitstring( &c, buf, &ns_cert_type, 8 );
120 if( ret < 3 || ret > 4 )
123 ret = mbedtls_x509write_csr_set_extension( ctx, MBEDTLS_OID_NS_CERT_TYPE,
124 MBEDTLS_OID_SIZE( MBEDTLS_OID_NS_CERT_TYPE ),
132 int mbedtls_x509write_csr_der( mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size,
133 int (*f_rng)(void *, unsigned char *, size_t),
138 size_t sig_oid_len = 0;
139 unsigned char *c, *c2;
140 unsigned char hash[64];
141 unsigned char sig[MBEDTLS_MPI_MAX_SIZE];
142 unsigned char tmp_buf[2048];
143 size_t pub_len = 0, sig_and_oid_len = 0, sig_len;
145 mbedtls_pk_type_t pk_alg;
146 #if defined(MBEDTLS_USE_PSA_CRYPTO)
147 psa_hash_operation_t hash_operation = PSA_HASH_OPERATION_INIT;
149 psa_algorithm_t hash_alg = mbedtls_psa_translate_md( ctx->md_alg );
150 #endif /* MBEDTLS_USE_PSA_CRYPTO */
152 * Prepare data to be signed in tmp_buf
154 c = tmp_buf + sizeof( tmp_buf );
156 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_x509_write_extensions( &c, tmp_buf, ctx->extensions ) );
160 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
161 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
162 MBEDTLS_ASN1_SEQUENCE ) );
164 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
165 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
166 MBEDTLS_ASN1_SET ) );
168 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_oid( &c, tmp_buf, MBEDTLS_OID_PKCS9_CSR_EXT_REQ,
169 MBEDTLS_OID_SIZE( MBEDTLS_OID_PKCS9_CSR_EXT_REQ ) ) );
171 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
172 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
173 MBEDTLS_ASN1_SEQUENCE ) );
176 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
177 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
178 MBEDTLS_ASN1_CONTEXT_SPECIFIC ) );
180 MBEDTLS_ASN1_CHK_ADD( pub_len, mbedtls_pk_write_pubkey_der( ctx->key,
181 tmp_buf, c - tmp_buf ) );
188 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_x509_write_names( &c, tmp_buf, ctx->subject ) );
191 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
193 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_int( &c, tmp_buf, 0 ) );
195 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, tmp_buf, len ) );
196 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, tmp_buf, MBEDTLS_ASN1_CONSTRUCTED |
197 MBEDTLS_ASN1_SEQUENCE ) );
201 * Note: hash errors can happen only after an internal error
203 #if defined(MBEDTLS_USE_PSA_CRYPTO)
204 if( psa_hash_setup( &hash_operation, hash_alg ) != PSA_SUCCESS )
205 return( MBEDTLS_ERR_X509_FATAL_ERROR );
207 if( psa_hash_update( &hash_operation, c, len ) != PSA_SUCCESS )
208 return( MBEDTLS_ERR_X509_FATAL_ERROR );
210 if( psa_hash_finish( &hash_operation, hash, sizeof( hash ), &hash_len )
213 return( MBEDTLS_ERR_X509_FATAL_ERROR );
215 #else /* MBEDTLS_USE_PSA_CRYPTO */
216 mbedtls_md( mbedtls_md_info_from_type( ctx->md_alg ), c, len, hash );
218 if( ( ret = mbedtls_pk_sign( ctx->key, ctx->md_alg, hash, 0, sig, &sig_len,
219 f_rng, p_rng ) ) != 0 )
224 if( mbedtls_pk_can_do( ctx->key, MBEDTLS_PK_RSA ) )
225 pk_alg = MBEDTLS_PK_RSA;
226 else if( mbedtls_pk_can_do( ctx->key, MBEDTLS_PK_ECDSA ) )
227 pk_alg = MBEDTLS_PK_ECDSA;
229 return( MBEDTLS_ERR_X509_INVALID_ALG );
231 if( ( ret = mbedtls_oid_get_oid_by_sig_alg( pk_alg, ctx->md_alg,
232 &sig_oid, &sig_oid_len ) ) != 0 )
238 * Write data to output buffer
241 MBEDTLS_ASN1_CHK_ADD( sig_and_oid_len, mbedtls_x509_write_sig( &c2, buf,
242 sig_oid, sig_oid_len, sig, sig_len ) );
244 if( len > (size_t)( c2 - buf ) )
245 return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL );
248 memcpy( c2, c, len );
250 len += sig_and_oid_len;
251 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c2, buf, len ) );
252 MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c2, buf, MBEDTLS_ASN1_CONSTRUCTED |
253 MBEDTLS_ASN1_SEQUENCE ) );
258 #define PEM_BEGIN_CSR "-----BEGIN CERTIFICATE REQUEST-----\n"
259 #define PEM_END_CSR "-----END CERTIFICATE REQUEST-----\n"
261 #if defined(MBEDTLS_PEM_WRITE_C)
262 int mbedtls_x509write_csr_pem( mbedtls_x509write_csr *ctx, unsigned char *buf, size_t size,
263 int (*f_rng)(void *, unsigned char *, size_t),
267 unsigned char output_buf[4096];
270 if( ( ret = mbedtls_x509write_csr_der( ctx, output_buf, sizeof(output_buf),
271 f_rng, p_rng ) ) < 0 )
276 if( ( ret = mbedtls_pem_write_buffer( PEM_BEGIN_CSR, PEM_END_CSR,
277 output_buf + sizeof(output_buf) - ret,
278 ret, buf, size, &olen ) ) != 0 )
285 #endif /* MBEDTLS_PEM_WRITE_C */
287 #endif /* MBEDTLS_X509_CSR_WRITE_C */