1 /*
2 * Certificate request generation
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0
6 *
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
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
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.
18 */
19
20 #include "mbedtls/build_info.h"
21
22 #include "mbedtls/platform.h"
23
24 #if !defined(MBEDTLS_X509_CSR_WRITE_C) || !defined(MBEDTLS_FS_IO) || \
25 !defined(MBEDTLS_PK_PARSE_C) || !defined(MBEDTLS_SHA256_C) || \
26 !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C) || \
27 !defined(MBEDTLS_PEM_WRITE_C)
main(void)28 int main( void )
29 {
30 mbedtls_printf( "MBEDTLS_X509_CSR_WRITE_C and/or MBEDTLS_FS_IO and/or "
31 "MBEDTLS_PK_PARSE_C and/or MBEDTLS_SHA256_C and/or "
32 "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C "
33 "not defined.\n");
34 mbedtls_exit( 0 );
35 }
36 #else
37
38 #include "mbedtls/x509_csr.h"
39 #include "mbedtls/entropy.h"
40 #include "mbedtls/ctr_drbg.h"
41 #include "mbedtls/error.h"
42
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46
47 #define DFL_FILENAME "keyfile.key"
48 #define DFL_PASSWORD NULL
49 #define DFL_DEBUG_LEVEL 0
50 #define DFL_OUTPUT_FILENAME "cert.req"
51 #define DFL_SUBJECT_NAME "CN=Cert,O=mbed TLS,C=UK"
52 #define DFL_KEY_USAGE 0
53 #define DFL_FORCE_KEY_USAGE 0
54 #define DFL_NS_CERT_TYPE 0
55 #define DFL_FORCE_NS_CERT_TYPE 0
56 #define DFL_MD_ALG MBEDTLS_MD_SHA256
57
58 #define USAGE \
59 "\n usage: cert_req param=<>...\n" \
60 "\n acceptable parameters:\n" \
61 " filename=%%s default: keyfile.key\n" \
62 " password=%%s default: NULL\n" \
63 " debug_level=%%d default: 0 (disabled)\n" \
64 " output_file=%%s default: cert.req\n" \
65 " subject_name=%%s default: CN=Cert,O=mbed TLS,C=UK\n" \
66 " key_usage=%%s default: (empty)\n" \
67 " Comma-separated-list of values:\n" \
68 " digital_signature\n" \
69 " non_repudiation\n" \
70 " key_encipherment\n" \
71 " data_encipherment\n" \
72 " key_agreement\n" \
73 " key_cert_sign\n" \
74 " crl_sign\n" \
75 " force_key_usage=0/1 default: off\n" \
76 " Add KeyUsage even if it is empty\n" \
77 " ns_cert_type=%%s default: (empty)\n" \
78 " Comma-separated-list of values:\n" \
79 " ssl_client\n" \
80 " ssl_server\n" \
81 " email\n" \
82 " object_signing\n" \
83 " ssl_ca\n" \
84 " email_ca\n" \
85 " object_signing_ca\n" \
86 " force_ns_cert_type=0/1 default: off\n" \
87 " Add NsCertType even if it is empty\n" \
88 " md=%%s default: SHA256\n" \
89 " possible values:\n" \
90 " MD5, RIPEMD160, SHA1,\n" \
91 " SHA224, SHA256, SHA384, SHA512\n" \
92 "\n"
93
94
95 /*
96 * global options
97 */
98 struct options
99 {
100 const char *filename; /* filename of the key file */
101 const char *password; /* password for the key file */
102 int debug_level; /* level of debugging */
103 const char *output_file; /* where to store the constructed key file */
104 const char *subject_name; /* subject name for certificate request */
105 unsigned char key_usage; /* key usage flags */
106 int force_key_usage; /* Force adding the KeyUsage extension */
107 unsigned char ns_cert_type; /* NS cert type */
108 int force_ns_cert_type; /* Force adding NsCertType extension */
109 mbedtls_md_type_t md_alg; /* Hash algorithm used for signature. */
110 } opt;
111
write_certificate_request(mbedtls_x509write_csr * req,const char * output_file,int (* f_rng)(void *,unsigned char *,size_t),void * p_rng)112 int write_certificate_request( mbedtls_x509write_csr *req, const char *output_file,
113 int (*f_rng)(void *, unsigned char *, size_t),
114 void *p_rng )
115 {
116 int ret;
117 FILE *f;
118 unsigned char output_buf[4096];
119 size_t len = 0;
120
121 memset( output_buf, 0, 4096 );
122 if( ( ret = mbedtls_x509write_csr_pem( req, output_buf, 4096, f_rng, p_rng ) ) < 0 )
123 return( ret );
124
125 len = strlen( (char *) output_buf );
126
127 if( ( f = fopen( output_file, "w" ) ) == NULL )
128 return( -1 );
129
130 if( fwrite( output_buf, 1, len, f ) != len )
131 {
132 fclose( f );
133 return( -1 );
134 }
135
136 fclose( f );
137
138 return( 0 );
139 }
140
main(int argc,char * argv[])141 int main( int argc, char *argv[] )
142 {
143 int ret = 1;
144 int exit_code = MBEDTLS_EXIT_FAILURE;
145 mbedtls_pk_context key;
146 char buf[1024];
147 int i;
148 char *p, *q, *r;
149 mbedtls_x509write_csr req;
150 mbedtls_entropy_context entropy;
151 mbedtls_ctr_drbg_context ctr_drbg;
152 const char *pers = "csr example app";
153
154 /*
155 * Set to sane values
156 */
157 mbedtls_x509write_csr_init( &req );
158 mbedtls_pk_init( &key );
159 mbedtls_ctr_drbg_init( &ctr_drbg );
160 memset( buf, 0, sizeof( buf ) );
161
162 if( argc == 0 )
163 {
164 usage:
165 mbedtls_printf( USAGE );
166 goto exit;
167 }
168
169 opt.filename = DFL_FILENAME;
170 opt.password = DFL_PASSWORD;
171 opt.debug_level = DFL_DEBUG_LEVEL;
172 opt.output_file = DFL_OUTPUT_FILENAME;
173 opt.subject_name = DFL_SUBJECT_NAME;
174 opt.key_usage = DFL_KEY_USAGE;
175 opt.force_key_usage = DFL_FORCE_KEY_USAGE;
176 opt.ns_cert_type = DFL_NS_CERT_TYPE;
177 opt.force_ns_cert_type = DFL_FORCE_NS_CERT_TYPE;
178 opt.md_alg = DFL_MD_ALG;
179
180 for( i = 1; i < argc; i++ )
181 {
182
183 p = argv[i];
184 if( ( q = strchr( p, '=' ) ) == NULL )
185 goto usage;
186 *q++ = '\0';
187
188 if( strcmp( p, "filename" ) == 0 )
189 opt.filename = q;
190 else if( strcmp( p, "password" ) == 0 )
191 opt.password = q;
192 else if( strcmp( p, "output_file" ) == 0 )
193 opt.output_file = q;
194 else if( strcmp( p, "debug_level" ) == 0 )
195 {
196 opt.debug_level = atoi( q );
197 if( opt.debug_level < 0 || opt.debug_level > 65535 )
198 goto usage;
199 }
200 else if( strcmp( p, "subject_name" ) == 0 )
201 {
202 opt.subject_name = q;
203 }
204 else if( strcmp( p, "md" ) == 0 )
205 {
206 const mbedtls_md_info_t *md_info =
207 mbedtls_md_info_from_string( q );
208 if( md_info == NULL )
209 {
210 mbedtls_printf( "Invalid argument for option %s\n", p );
211 goto usage;
212 }
213 opt.md_alg = mbedtls_md_get_type( md_info );
214 }
215 else if( strcmp( p, "key_usage" ) == 0 )
216 {
217 while( q != NULL )
218 {
219 if( ( r = strchr( q, ',' ) ) != NULL )
220 *r++ = '\0';
221
222 if( strcmp( q, "digital_signature" ) == 0 )
223 opt.key_usage |= MBEDTLS_X509_KU_DIGITAL_SIGNATURE;
224 else if( strcmp( q, "non_repudiation" ) == 0 )
225 opt.key_usage |= MBEDTLS_X509_KU_NON_REPUDIATION;
226 else if( strcmp( q, "key_encipherment" ) == 0 )
227 opt.key_usage |= MBEDTLS_X509_KU_KEY_ENCIPHERMENT;
228 else if( strcmp( q, "data_encipherment" ) == 0 )
229 opt.key_usage |= MBEDTLS_X509_KU_DATA_ENCIPHERMENT;
230 else if( strcmp( q, "key_agreement" ) == 0 )
231 opt.key_usage |= MBEDTLS_X509_KU_KEY_AGREEMENT;
232 else if( strcmp( q, "key_cert_sign" ) == 0 )
233 opt.key_usage |= MBEDTLS_X509_KU_KEY_CERT_SIGN;
234 else if( strcmp( q, "crl_sign" ) == 0 )
235 opt.key_usage |= MBEDTLS_X509_KU_CRL_SIGN;
236 else
237 goto usage;
238
239 q = r;
240 }
241 }
242 else if( strcmp( p, "force_key_usage" ) == 0 )
243 {
244 switch( atoi( q ) )
245 {
246 case 0: opt.force_key_usage = 0; break;
247 case 1: opt.force_key_usage = 1; break;
248 default: goto usage;
249 }
250 }
251 else if( strcmp( p, "ns_cert_type" ) == 0 )
252 {
253 while( q != NULL )
254 {
255 if( ( r = strchr( q, ',' ) ) != NULL )
256 *r++ = '\0';
257
258 if( strcmp( q, "ssl_client" ) == 0 )
259 opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT;
260 else if( strcmp( q, "ssl_server" ) == 0 )
261 opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER;
262 else if( strcmp( q, "email" ) == 0 )
263 opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_EMAIL;
264 else if( strcmp( q, "object_signing" ) == 0 )
265 opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING;
266 else if( strcmp( q, "ssl_ca" ) == 0 )
267 opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_SSL_CA;
268 else if( strcmp( q, "email_ca" ) == 0 )
269 opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA;
270 else if( strcmp( q, "object_signing_ca" ) == 0 )
271 opt.ns_cert_type |= MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA;
272 else
273 goto usage;
274
275 q = r;
276 }
277 }
278 else if( strcmp( p, "force_ns_cert_type" ) == 0 )
279 {
280 switch( atoi( q ) )
281 {
282 case 0: opt.force_ns_cert_type = 0; break;
283 case 1: opt.force_ns_cert_type = 1; break;
284 default: goto usage;
285 }
286 }
287 else
288 goto usage;
289 }
290
291 mbedtls_x509write_csr_set_md_alg( &req, opt.md_alg );
292
293 if( opt.key_usage || opt.force_key_usage == 1 )
294 mbedtls_x509write_csr_set_key_usage( &req, opt.key_usage );
295
296 if( opt.ns_cert_type || opt.force_ns_cert_type == 1 )
297 mbedtls_x509write_csr_set_ns_cert_type( &req, opt.ns_cert_type );
298
299 /*
300 * 0. Seed the PRNG
301 */
302 mbedtls_printf( " . Seeding the random number generator..." );
303 fflush( stdout );
304
305 mbedtls_entropy_init( &entropy );
306 if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
307 (const unsigned char *) pers,
308 strlen( pers ) ) ) != 0 )
309 {
310 mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d", ret );
311 goto exit;
312 }
313
314 mbedtls_printf( " ok\n" );
315
316 /*
317 * 1.0. Check the subject name for validity
318 */
319 mbedtls_printf( " . Checking subject name..." );
320 fflush( stdout );
321
322 if( ( ret = mbedtls_x509write_csr_set_subject_name( &req, opt.subject_name ) ) != 0 )
323 {
324 mbedtls_printf( " failed\n ! mbedtls_x509write_csr_set_subject_name returned %d", ret );
325 goto exit;
326 }
327
328 mbedtls_printf( " ok\n" );
329
330 /*
331 * 1.1. Load the key
332 */
333 mbedtls_printf( " . Loading the private key ..." );
334 fflush( stdout );
335
336 ret = mbedtls_pk_parse_keyfile( &key, opt.filename, opt.password,
337 mbedtls_ctr_drbg_random, &ctr_drbg );
338
339 if( ret != 0 )
340 {
341 mbedtls_printf( " failed\n ! mbedtls_pk_parse_keyfile returned %d", ret );
342 goto exit;
343 }
344
345 mbedtls_x509write_csr_set_key( &req, &key );
346
347 mbedtls_printf( " ok\n" );
348
349 /*
350 * 1.2. Writing the request
351 */
352 mbedtls_printf( " . Writing the certificate request ..." );
353 fflush( stdout );
354
355 if( ( ret = write_certificate_request( &req, opt.output_file,
356 mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )
357 {
358 mbedtls_printf( " failed\n ! write_certificate_request %d", ret );
359 goto exit;
360 }
361
362 mbedtls_printf( " ok\n" );
363
364 exit_code = MBEDTLS_EXIT_SUCCESS;
365
366 exit:
367
368 if( exit_code != MBEDTLS_EXIT_SUCCESS )
369 {
370 #ifdef MBEDTLS_ERROR_C
371 mbedtls_strerror( ret, buf, sizeof( buf ) );
372 mbedtls_printf( " - %s\n", buf );
373 #else
374 mbedtls_printf("\n");
375 #endif
376 }
377
378 mbedtls_x509write_csr_free( &req );
379 mbedtls_pk_free( &key );
380 mbedtls_ctr_drbg_free( &ctr_drbg );
381 mbedtls_entropy_free( &entropy );
382
383 mbedtls_exit( exit_code );
384 }
385 #endif /* MBEDTLS_X509_CSR_WRITE_C && MBEDTLS_PK_PARSE_C && MBEDTLS_FS_IO &&
386 MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C && MBEDTLS_PEM_WRITE_C */
387
