1 /*
2 * X.509 certificate writing
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 */
7 /*
8 * References:
9 * - certificates: RFC 5280, updated by RFC 6818
10 * - CSRs: PKCS#10 v1.7 aka RFC 2986
11 * - attributes: PKCS#9 v2.0 aka RFC 2985
12 */
13
14 #include "common.h"
15
16 #if defined(MBEDTLS_X509_CRT_WRITE_C)
17
18 #include "mbedtls/x509_crt.h"
19 #include "mbedtls/asn1write.h"
20 #include "mbedtls/error.h"
21 #include "mbedtls/oid.h"
22 #include "mbedtls/platform_util.h"
23 #include "mbedtls/sha1.h"
24
25 #include <string.h>
26
27 #if defined(MBEDTLS_PEM_WRITE_C)
28 #include "mbedtls/pem.h"
29 #endif /* MBEDTLS_PEM_WRITE_C */
30
mbedtls_x509write_crt_init(mbedtls_x509write_cert * ctx)31 void mbedtls_x509write_crt_init(mbedtls_x509write_cert *ctx)
32 {
33 memset(ctx, 0, sizeof(mbedtls_x509write_cert));
34
35 mbedtls_mpi_init(&ctx->serial);
36 ctx->version = MBEDTLS_X509_CRT_VERSION_3;
37 }
38
mbedtls_x509write_crt_free(mbedtls_x509write_cert * ctx)39 void mbedtls_x509write_crt_free(mbedtls_x509write_cert *ctx)
40 {
41 mbedtls_mpi_free(&ctx->serial);
42
43 mbedtls_asn1_free_named_data_list(&ctx->subject);
44 mbedtls_asn1_free_named_data_list(&ctx->issuer);
45 mbedtls_asn1_free_named_data_list(&ctx->extensions);
46
47 mbedtls_platform_zeroize(ctx, sizeof(mbedtls_x509write_cert));
48 }
49
mbedtls_x509write_crt_set_version(mbedtls_x509write_cert * ctx,int version)50 void mbedtls_x509write_crt_set_version(mbedtls_x509write_cert *ctx,
51 int version)
52 {
53 ctx->version = version;
54 }
55
mbedtls_x509write_crt_set_md_alg(mbedtls_x509write_cert * ctx,mbedtls_md_type_t md_alg)56 void mbedtls_x509write_crt_set_md_alg(mbedtls_x509write_cert *ctx,
57 mbedtls_md_type_t md_alg)
58 {
59 ctx->md_alg = md_alg;
60 }
61
mbedtls_x509write_crt_set_subject_key(mbedtls_x509write_cert * ctx,mbedtls_pk_context * key)62 void mbedtls_x509write_crt_set_subject_key(mbedtls_x509write_cert *ctx,
63 mbedtls_pk_context *key)
64 {
65 ctx->subject_key = key;
66 }
67
mbedtls_x509write_crt_set_issuer_key(mbedtls_x509write_cert * ctx,mbedtls_pk_context * key)68 void mbedtls_x509write_crt_set_issuer_key(mbedtls_x509write_cert *ctx,
69 mbedtls_pk_context *key)
70 {
71 ctx->issuer_key = key;
72 }
73
mbedtls_x509write_crt_set_subject_name(mbedtls_x509write_cert * ctx,const char * subject_name)74 int mbedtls_x509write_crt_set_subject_name(mbedtls_x509write_cert *ctx,
75 const char *subject_name)
76 {
77 return mbedtls_x509_string_to_names(&ctx->subject, subject_name);
78 }
79
mbedtls_x509write_crt_set_issuer_name(mbedtls_x509write_cert * ctx,const char * issuer_name)80 int mbedtls_x509write_crt_set_issuer_name(mbedtls_x509write_cert *ctx,
81 const char *issuer_name)
82 {
83 return mbedtls_x509_string_to_names(&ctx->issuer, issuer_name);
84 }
85
mbedtls_x509write_crt_set_serial(mbedtls_x509write_cert * ctx,const mbedtls_mpi * serial)86 int mbedtls_x509write_crt_set_serial(mbedtls_x509write_cert *ctx,
87 const mbedtls_mpi *serial)
88 {
89 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
90
91 if (mbedtls_mpi_size(serial) > MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN) {
92 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
93 }
94
95 if ((ret = mbedtls_mpi_copy(&ctx->serial, serial)) != 0) {
96 return ret;
97 }
98
99 return 0;
100 }
101
mbedtls_x509write_crt_set_validity(mbedtls_x509write_cert * ctx,const char * not_before,const char * not_after)102 int mbedtls_x509write_crt_set_validity(mbedtls_x509write_cert *ctx,
103 const char *not_before,
104 const char *not_after)
105 {
106 if (strlen(not_before) != MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1 ||
107 strlen(not_after) != MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1) {
108 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
109 }
110 strncpy(ctx->not_before, not_before, MBEDTLS_X509_RFC5280_UTC_TIME_LEN);
111 strncpy(ctx->not_after, not_after, MBEDTLS_X509_RFC5280_UTC_TIME_LEN);
112 ctx->not_before[MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1] = 'Z';
113 ctx->not_after[MBEDTLS_X509_RFC5280_UTC_TIME_LEN - 1] = 'Z';
114
115 return 0;
116 }
117
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)118 int mbedtls_x509write_crt_set_extension(mbedtls_x509write_cert *ctx,
119 const char *oid, size_t oid_len,
120 int critical,
121 const unsigned char *val, size_t val_len)
122 {
123 return mbedtls_x509_set_extension(&ctx->extensions, oid, oid_len,
124 critical, val, val_len);
125 }
126
mbedtls_x509write_crt_set_basic_constraints(mbedtls_x509write_cert * ctx,int is_ca,int max_pathlen)127 int mbedtls_x509write_crt_set_basic_constraints(mbedtls_x509write_cert *ctx,
128 int is_ca, int max_pathlen)
129 {
130 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
131 unsigned char buf[9];
132 unsigned char *c = buf + sizeof(buf);
133 size_t len = 0;
134
135 memset(buf, 0, sizeof(buf));
136
137 if (is_ca && max_pathlen > 127) {
138 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
139 }
140
141 if (is_ca) {
142 if (max_pathlen >= 0) {
143 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_int(&c, buf,
144 max_pathlen));
145 }
146 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_bool(&c, buf, 1));
147 }
148
149 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
150 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf,
151 MBEDTLS_ASN1_CONSTRUCTED |
152 MBEDTLS_ASN1_SEQUENCE));
153
154 return
155 mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_BASIC_CONSTRAINTS,
156 MBEDTLS_OID_SIZE(MBEDTLS_OID_BASIC_CONSTRAINTS),
157 is_ca, buf + sizeof(buf) - len, len);
158 }
159
160 #if defined(MBEDTLS_SHA1_C)
mbedtls_x509write_crt_set_subject_key_identifier(mbedtls_x509write_cert * ctx)161 int mbedtls_x509write_crt_set_subject_key_identifier(mbedtls_x509write_cert *ctx)
162 {
163 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
164 unsigned char buf[MBEDTLS_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */
165 unsigned char *c = buf + sizeof(buf);
166 size_t len = 0;
167
168 memset(buf, 0, sizeof(buf));
169 MBEDTLS_ASN1_CHK_ADD(len,
170 mbedtls_pk_write_pubkey(&c, buf, ctx->subject_key));
171
172 ret = mbedtls_sha1_ret(buf + sizeof(buf) - len, len,
173 buf + sizeof(buf) - 20);
174 if (ret != 0) {
175 return ret;
176 }
177 c = buf + sizeof(buf) - 20;
178 len = 20;
179
180 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
181 MBEDTLS_ASN1_CHK_ADD(len,
182 mbedtls_asn1_write_tag(&c, buf, MBEDTLS_ASN1_OCTET_STRING));
183
184 return mbedtls_x509write_crt_set_extension(ctx,
185 MBEDTLS_OID_SUBJECT_KEY_IDENTIFIER,
186 MBEDTLS_OID_SIZE(MBEDTLS_OID_SUBJECT_KEY_IDENTIFIER),
187 0, buf + sizeof(buf) - len, len);
188 }
189
mbedtls_x509write_crt_set_authority_key_identifier(mbedtls_x509write_cert * ctx)190 int mbedtls_x509write_crt_set_authority_key_identifier(mbedtls_x509write_cert *ctx)
191 {
192 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
193 unsigned char buf[MBEDTLS_MPI_MAX_SIZE * 2 + 20]; /* tag, length + 2xMPI */
194 unsigned char *c = buf + sizeof(buf);
195 size_t len = 0;
196
197 memset(buf, 0, sizeof(buf));
198 MBEDTLS_ASN1_CHK_ADD(len,
199 mbedtls_pk_write_pubkey(&c, buf, ctx->issuer_key));
200
201 ret = mbedtls_sha1_ret(buf + sizeof(buf) - len, len,
202 buf + sizeof(buf) - 20);
203 if (ret != 0) {
204 return ret;
205 }
206 c = buf + sizeof(buf) - 20;
207 len = 20;
208
209 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
210 MBEDTLS_ASN1_CHK_ADD(len,
211 mbedtls_asn1_write_tag(&c, buf, MBEDTLS_ASN1_CONTEXT_SPECIFIC | 0));
212
213 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
214 MBEDTLS_ASN1_CHK_ADD(len,
215 mbedtls_asn1_write_tag(&c, buf,
216 MBEDTLS_ASN1_CONSTRUCTED |
217 MBEDTLS_ASN1_SEQUENCE));
218
219 return mbedtls_x509write_crt_set_extension(
220 ctx, MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER,
221 MBEDTLS_OID_SIZE(MBEDTLS_OID_AUTHORITY_KEY_IDENTIFIER),
222 0, buf + sizeof(buf) - len, len);
223 }
224 #endif /* MBEDTLS_SHA1_C */
225
mbedtls_x509write_crt_set_key_usage(mbedtls_x509write_cert * ctx,unsigned int key_usage)226 int mbedtls_x509write_crt_set_key_usage(mbedtls_x509write_cert *ctx,
227 unsigned int key_usage)
228 {
229 unsigned char buf[5] = { 0 }, ku[2] = { 0 };
230 unsigned char *c;
231 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
232 const unsigned int allowed_bits = MBEDTLS_X509_KU_DIGITAL_SIGNATURE |
233 MBEDTLS_X509_KU_NON_REPUDIATION |
234 MBEDTLS_X509_KU_KEY_ENCIPHERMENT |
235 MBEDTLS_X509_KU_DATA_ENCIPHERMENT |
236 MBEDTLS_X509_KU_KEY_AGREEMENT |
237 MBEDTLS_X509_KU_KEY_CERT_SIGN |
238 MBEDTLS_X509_KU_CRL_SIGN |
239 MBEDTLS_X509_KU_ENCIPHER_ONLY |
240 MBEDTLS_X509_KU_DECIPHER_ONLY;
241
242 /* Check that nothing other than the allowed flags is set */
243 if ((key_usage & ~allowed_bits) != 0) {
244 return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
245 }
246
247 c = buf + 5;
248 MBEDTLS_PUT_UINT16_LE(key_usage, ku, 0);
249 ret = mbedtls_asn1_write_named_bitstring(&c, buf, ku, 9);
250
251 if (ret < 0) {
252 return ret;
253 } else if (ret < 3 || ret > 5) {
254 return MBEDTLS_ERR_X509_INVALID_FORMAT;
255 }
256
257 ret = mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_KEY_USAGE,
258 MBEDTLS_OID_SIZE(MBEDTLS_OID_KEY_USAGE),
259 1, c, (size_t) ret);
260 if (ret != 0) {
261 return ret;
262 }
263
264 return 0;
265 }
266
mbedtls_x509write_crt_set_ns_cert_type(mbedtls_x509write_cert * ctx,unsigned char ns_cert_type)267 int mbedtls_x509write_crt_set_ns_cert_type(mbedtls_x509write_cert *ctx,
268 unsigned char ns_cert_type)
269 {
270 unsigned char buf[4] = { 0 };
271 unsigned char *c;
272 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
273
274 c = buf + 4;
275
276 ret = mbedtls_asn1_write_named_bitstring(&c, buf, &ns_cert_type, 8);
277 if (ret < 3 || ret > 4) {
278 return ret;
279 }
280
281 ret = mbedtls_x509write_crt_set_extension(ctx, MBEDTLS_OID_NS_CERT_TYPE,
282 MBEDTLS_OID_SIZE(MBEDTLS_OID_NS_CERT_TYPE),
283 0, c, (size_t) ret);
284 if (ret != 0) {
285 return ret;
286 }
287
288 return 0;
289 }
290
x509_write_time(unsigned char ** p,unsigned char * start,const char * t,size_t size)291 static int x509_write_time(unsigned char **p, unsigned char *start,
292 const char *t, size_t size)
293 {
294 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
295 size_t len = 0;
296
297 /*
298 * write MBEDTLS_ASN1_UTC_TIME if year < 2050 (2 bytes shorter)
299 */
300 if (t[0] < '2' || (t[0] == '2' && t[1] == '0' && t[2] < '5')) {
301 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(p, start,
302 (const unsigned char *) t + 2,
303 size - 2));
304 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, start, len));
305 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, start,
306 MBEDTLS_ASN1_UTC_TIME));
307 } else {
308 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_raw_buffer(p, start,
309 (const unsigned char *) t,
310 size));
311 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(p, start, len));
312 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(p, start,
313 MBEDTLS_ASN1_GENERALIZED_TIME));
314 }
315
316 return (int) len;
317 }
318
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)319 int mbedtls_x509write_crt_der(mbedtls_x509write_cert *ctx,
320 unsigned char *buf, size_t size,
321 int (*f_rng)(void *, unsigned char *, size_t),
322 void *p_rng)
323 {
324 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
325 const char *sig_oid;
326 size_t sig_oid_len = 0;
327 unsigned char *c, *c2;
328 unsigned char hash[64];
329 unsigned char sig[MBEDTLS_PK_SIGNATURE_MAX_SIZE];
330 size_t sub_len = 0, pub_len = 0, sig_and_oid_len = 0, sig_len;
331 size_t len = 0;
332 mbedtls_pk_type_t pk_alg;
333 int write_sig_null_par;
334
335 /*
336 * Prepare data to be signed at the end of the target buffer
337 */
338 c = buf + size;
339
340 /* Signature algorithm needed in TBS, and later for actual signature */
341
342 /* There's no direct way of extracting a signature algorithm
343 * (represented as an element of mbedtls_pk_type_t) from a PK instance. */
344 if (mbedtls_pk_can_do(ctx->issuer_key, MBEDTLS_PK_RSA)) {
345 pk_alg = MBEDTLS_PK_RSA;
346 } else if (mbedtls_pk_can_do(ctx->issuer_key, MBEDTLS_PK_ECDSA)) {
347 pk_alg = MBEDTLS_PK_ECDSA;
348 } else {
349 return MBEDTLS_ERR_X509_INVALID_ALG;
350 }
351
352 if ((ret = mbedtls_oid_get_oid_by_sig_alg(pk_alg, ctx->md_alg,
353 &sig_oid, &sig_oid_len)) != 0) {
354 return ret;
355 }
356
357 /*
358 * Extensions ::= SEQUENCE SIZE (1..MAX) OF Extension
359 */
360
361 /* Only for v3 */
362 if (ctx->version == MBEDTLS_X509_CRT_VERSION_3) {
363 MBEDTLS_ASN1_CHK_ADD(len,
364 mbedtls_x509_write_extensions(&c,
365 buf, ctx->extensions));
366 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
367 MBEDTLS_ASN1_CHK_ADD(len,
368 mbedtls_asn1_write_tag(&c, buf,
369 MBEDTLS_ASN1_CONSTRUCTED |
370 MBEDTLS_ASN1_SEQUENCE));
371 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
372 MBEDTLS_ASN1_CHK_ADD(len,
373 mbedtls_asn1_write_tag(&c, buf,
374 MBEDTLS_ASN1_CONTEXT_SPECIFIC |
375 MBEDTLS_ASN1_CONSTRUCTED | 3));
376 }
377
378 /*
379 * SubjectPublicKeyInfo
380 */
381 MBEDTLS_ASN1_CHK_ADD(pub_len,
382 mbedtls_pk_write_pubkey_der(ctx->subject_key,
383 buf, c - buf));
384 c -= pub_len;
385 len += pub_len;
386
387 /*
388 * Subject ::= Name
389 */
390 MBEDTLS_ASN1_CHK_ADD(len,
391 mbedtls_x509_write_names(&c, buf,
392 ctx->subject));
393
394 /*
395 * Validity ::= SEQUENCE {
396 * notBefore Time,
397 * notAfter Time }
398 */
399 sub_len = 0;
400
401 MBEDTLS_ASN1_CHK_ADD(sub_len,
402 x509_write_time(&c, buf, ctx->not_after,
403 MBEDTLS_X509_RFC5280_UTC_TIME_LEN));
404
405 MBEDTLS_ASN1_CHK_ADD(sub_len,
406 x509_write_time(&c, buf, ctx->not_before,
407 MBEDTLS_X509_RFC5280_UTC_TIME_LEN));
408
409 len += sub_len;
410 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, sub_len));
411 MBEDTLS_ASN1_CHK_ADD(len,
412 mbedtls_asn1_write_tag(&c, buf,
413 MBEDTLS_ASN1_CONSTRUCTED |
414 MBEDTLS_ASN1_SEQUENCE));
415
416 /*
417 * Issuer ::= Name
418 */
419 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_x509_write_names(&c, buf,
420 ctx->issuer));
421
422 /*
423 * Signature ::= AlgorithmIdentifier
424 */
425 if (pk_alg == MBEDTLS_PK_ECDSA) {
426 /*
427 * The AlgorithmIdentifier's parameters field must be absent for DSA/ECDSA signature
428 * algorithms, see https://www.rfc-editor.org/rfc/rfc5480#page-17 and
429 * https://www.rfc-editor.org/rfc/rfc5758#section-3.
430 */
431 write_sig_null_par = 0;
432 } else {
433 write_sig_null_par = 1;
434 }
435 MBEDTLS_ASN1_CHK_ADD(len,
436 mbedtls_asn1_write_algorithm_identifier_ext(&c, buf,
437 sig_oid, strlen(sig_oid),
438 0, write_sig_null_par));
439
440 /*
441 * Serial ::= INTEGER
442 */
443 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_mpi(&c, buf,
444 &ctx->serial));
445
446 /*
447 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
448 */
449
450 /* Can be omitted for v1 */
451 if (ctx->version != MBEDTLS_X509_CRT_VERSION_1) {
452 sub_len = 0;
453 MBEDTLS_ASN1_CHK_ADD(sub_len,
454 mbedtls_asn1_write_int(&c, buf, ctx->version));
455 len += sub_len;
456 MBEDTLS_ASN1_CHK_ADD(len,
457 mbedtls_asn1_write_len(&c, buf, sub_len));
458 MBEDTLS_ASN1_CHK_ADD(len,
459 mbedtls_asn1_write_tag(&c, buf,
460 MBEDTLS_ASN1_CONTEXT_SPECIFIC |
461 MBEDTLS_ASN1_CONSTRUCTED | 0));
462 }
463
464 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
465 MBEDTLS_ASN1_CHK_ADD(len,
466 mbedtls_asn1_write_tag(&c, buf, MBEDTLS_ASN1_CONSTRUCTED |
467 MBEDTLS_ASN1_SEQUENCE));
468
469 /*
470 * Make signature
471 */
472
473 /* Compute hash of CRT. */
474 if ((ret = mbedtls_md(mbedtls_md_info_from_type(ctx->md_alg), c,
475 len, hash)) != 0) {
476 return ret;
477 }
478
479 if ((ret = mbedtls_pk_sign(ctx->issuer_key, ctx->md_alg,
480 hash, 0, sig, &sig_len,
481 f_rng, p_rng)) != 0) {
482 return ret;
483 }
484
485 /* Move CRT to the front of the buffer to have space
486 * for the signature. */
487 memmove(buf, c, len);
488 c = buf + len;
489
490 /* Add signature at the end of the buffer,
491 * making sure that it doesn't underflow
492 * into the CRT buffer. */
493 c2 = buf + size;
494 MBEDTLS_ASN1_CHK_ADD(sig_and_oid_len, mbedtls_x509_write_sig(&c2, c,
495 sig_oid, sig_oid_len,
496 sig, sig_len, pk_alg));
497
498 /*
499 * Memory layout after this step:
500 *
501 * buf c=buf+len c2 buf+size
502 * [CRT0,...,CRTn, UNUSED, ..., UNUSED, SIG0, ..., SIGm]
503 */
504
505 /* Move raw CRT to just before the signature. */
506 c = c2 - len;
507 memmove(c, buf, len);
508
509 len += sig_and_oid_len;
510 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_len(&c, buf, len));
511 MBEDTLS_ASN1_CHK_ADD(len, mbedtls_asn1_write_tag(&c, buf,
512 MBEDTLS_ASN1_CONSTRUCTED |
513 MBEDTLS_ASN1_SEQUENCE));
514
515 return (int) len;
516 }
517
518 #define PEM_BEGIN_CRT "-----BEGIN CERTIFICATE-----\n"
519 #define PEM_END_CRT "-----END CERTIFICATE-----\n"
520
521 #if defined(MBEDTLS_PEM_WRITE_C)
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)522 int mbedtls_x509write_crt_pem(mbedtls_x509write_cert *crt,
523 unsigned char *buf, size_t size,
524 int (*f_rng)(void *, unsigned char *, size_t),
525 void *p_rng)
526 {
527 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
528 size_t olen;
529
530 if ((ret = mbedtls_x509write_crt_der(crt, buf, size,
531 f_rng, p_rng)) < 0) {
532 return ret;
533 }
534
535 if ((ret = mbedtls_pem_write_buffer(PEM_BEGIN_CRT, PEM_END_CRT,
536 buf + size - ret, ret,
537 buf, size, &olen)) != 0) {
538 return ret;
539 }
540
541 return 0;
542 }
543 #endif /* MBEDTLS_PEM_WRITE_C */
544
545 #endif /* MBEDTLS_X509_CRT_WRITE_C */
546