1 /*
2 * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <stdio.h>
11 #include "internal/cryptlib.h"
12 #include <openssl/asn1.h>
13 #include <openssl/objects.h>
14 #include <openssl/x509.h>
15 #include <openssl/x509v3.h>
16 #include <openssl/core_names.h>
17 #include "crypto/x509.h"
18
X509_issuer_and_serial_cmp(const X509 * a,const X509 * b)19 int X509_issuer_and_serial_cmp(const X509 *a, const X509 *b)
20 {
21 int i;
22 const X509_CINF *ai, *bi;
23
24 if (b == NULL)
25 return a != NULL;
26 if (a == NULL)
27 return -1;
28 ai = &a->cert_info;
29 bi = &b->cert_info;
30 i = ASN1_INTEGER_cmp(&ai->serialNumber, &bi->serialNumber);
31 if (i != 0)
32 return i < 0 ? -1 : 1;
33 return X509_NAME_cmp(ai->issuer, bi->issuer);
34 }
35
36 #ifndef OPENSSL_NO_MD5
X509_issuer_and_serial_hash(X509 * a)37 unsigned long X509_issuer_and_serial_hash(X509 *a)
38 {
39 unsigned long ret = 0;
40 EVP_MD_CTX *ctx = EVP_MD_CTX_new();
41 unsigned char md[16];
42 char *f = NULL;
43 EVP_MD *digest = NULL;
44
45 if (ctx == NULL)
46 goto err;
47 f = X509_NAME_oneline(a->cert_info.issuer, NULL, 0);
48 if (f == NULL)
49 goto err;
50 digest = EVP_MD_fetch(a->libctx, SN_md5, a->propq);
51 if (digest == NULL)
52 goto err;
53
54 if (!EVP_DigestInit_ex(ctx, digest, NULL))
55 goto err;
56 if (!EVP_DigestUpdate(ctx, (unsigned char *)f, strlen(f)))
57 goto err;
58 if (!EVP_DigestUpdate
59 (ctx, (unsigned char *)a->cert_info.serialNumber.data,
60 (unsigned long)a->cert_info.serialNumber.length))
61 goto err;
62 if (!EVP_DigestFinal_ex(ctx, &(md[0]), NULL))
63 goto err;
64 ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
65 ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
66 ) & 0xffffffffL;
67 err:
68 OPENSSL_free(f);
69 EVP_MD_free(digest);
70 EVP_MD_CTX_free(ctx);
71 return ret;
72 }
73 #endif
74
X509_issuer_name_cmp(const X509 * a,const X509 * b)75 int X509_issuer_name_cmp(const X509 *a, const X509 *b)
76 {
77 return X509_NAME_cmp(a->cert_info.issuer, b->cert_info.issuer);
78 }
79
X509_subject_name_cmp(const X509 * a,const X509 * b)80 int X509_subject_name_cmp(const X509 *a, const X509 *b)
81 {
82 return X509_NAME_cmp(a->cert_info.subject, b->cert_info.subject);
83 }
84
X509_CRL_cmp(const X509_CRL * a,const X509_CRL * b)85 int X509_CRL_cmp(const X509_CRL *a, const X509_CRL *b)
86 {
87 return X509_NAME_cmp(a->crl.issuer, b->crl.issuer);
88 }
89
X509_CRL_match(const X509_CRL * a,const X509_CRL * b)90 int X509_CRL_match(const X509_CRL *a, const X509_CRL *b)
91 {
92 int rv;
93
94 if ((a->flags & EXFLAG_NO_FINGERPRINT) == 0
95 && (b->flags & EXFLAG_NO_FINGERPRINT) == 0)
96 rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
97 else
98 return -2;
99
100 return rv < 0 ? -1 : rv > 0;
101 }
102
X509_get_issuer_name(const X509 * a)103 X509_NAME *X509_get_issuer_name(const X509 *a)
104 {
105 return a->cert_info.issuer;
106 }
107
X509_issuer_name_hash(X509 * x)108 unsigned long X509_issuer_name_hash(X509 *x)
109 {
110 return X509_NAME_hash_ex(x->cert_info.issuer, NULL, NULL, NULL);
111 }
112
113 #ifndef OPENSSL_NO_MD5
X509_issuer_name_hash_old(X509 * x)114 unsigned long X509_issuer_name_hash_old(X509 *x)
115 {
116 return X509_NAME_hash_old(x->cert_info.issuer);
117 }
118 #endif
119
X509_get_subject_name(const X509 * a)120 X509_NAME *X509_get_subject_name(const X509 *a)
121 {
122 return a->cert_info.subject;
123 }
124
X509_get_serialNumber(X509 * a)125 ASN1_INTEGER *X509_get_serialNumber(X509 *a)
126 {
127 return &a->cert_info.serialNumber;
128 }
129
X509_get0_serialNumber(const X509 * a)130 const ASN1_INTEGER *X509_get0_serialNumber(const X509 *a)
131 {
132 return &a->cert_info.serialNumber;
133 }
134
X509_subject_name_hash(X509 * x)135 unsigned long X509_subject_name_hash(X509 *x)
136 {
137 return X509_NAME_hash_ex(x->cert_info.subject, NULL, NULL, NULL);
138 }
139
140 #ifndef OPENSSL_NO_MD5
X509_subject_name_hash_old(X509 * x)141 unsigned long X509_subject_name_hash_old(X509 *x)
142 {
143 return X509_NAME_hash_old(x->cert_info.subject);
144 }
145 #endif
146
147 /*
148 * Compare two certificates: they must be identical for this to work. NB:
149 * Although "cmp" operations are generally prototyped to take "const"
150 * arguments (eg. for use in STACKs), the way X509 handling is - these
151 * operations may involve ensuring the hashes are up-to-date and ensuring
152 * certain cert information is cached. So this is the point where the
153 * "depth-first" constification tree has to halt with an evil cast.
154 */
X509_cmp(const X509 * a,const X509 * b)155 int X509_cmp(const X509 *a, const X509 *b)
156 {
157 int rv = 0;
158
159 if (a == b) /* for efficiency */
160 return 0;
161
162 /* attempt to compute cert hash */
163 (void)X509_check_purpose((X509 *)a, -1, 0);
164 (void)X509_check_purpose((X509 *)b, -1, 0);
165
166 if ((a->ex_flags & EXFLAG_NO_FINGERPRINT) == 0
167 && (b->ex_flags & EXFLAG_NO_FINGERPRINT) == 0)
168 rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
169 if (rv != 0)
170 return rv < 0 ? -1 : 1;
171
172 /* Check for match against stored encoding too */
173 if (!a->cert_info.enc.modified && !b->cert_info.enc.modified) {
174 if (a->cert_info.enc.len < b->cert_info.enc.len)
175 return -1;
176 if (a->cert_info.enc.len > b->cert_info.enc.len)
177 return 1;
178 rv = memcmp(a->cert_info.enc.enc,
179 b->cert_info.enc.enc, a->cert_info.enc.len);
180 }
181 return rv < 0 ? -1 : rv > 0;
182 }
183
ossl_x509_add_cert_new(STACK_OF (X509)** p_sk,X509 * cert,int flags)184 int ossl_x509_add_cert_new(STACK_OF(X509) **p_sk, X509 *cert, int flags)
185 {
186 if (*p_sk == NULL && (*p_sk = sk_X509_new_null()) == NULL) {
187 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
188 return 0;
189 }
190 return X509_add_cert(*p_sk, cert, flags);
191 }
192
X509_add_cert(STACK_OF (X509)* sk,X509 * cert,int flags)193 int X509_add_cert(STACK_OF(X509) *sk, X509 *cert, int flags)
194 {
195 if (sk == NULL) {
196 ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
197 return 0;
198 }
199 if ((flags & X509_ADD_FLAG_NO_DUP) != 0) {
200 /*
201 * not using sk_X509_set_cmp_func() and sk_X509_find()
202 * because this re-orders the certs on the stack
203 */
204 int i;
205
206 for (i = 0; i < sk_X509_num(sk); i++) {
207 if (X509_cmp(sk_X509_value(sk, i), cert) == 0)
208 return 1;
209 }
210 }
211 if ((flags & X509_ADD_FLAG_NO_SS) != 0) {
212 int ret = X509_self_signed(cert, 0);
213
214 if (ret != 0)
215 return ret > 0 ? 1 : 0;
216 }
217 if (!sk_X509_insert(sk, cert,
218 (flags & X509_ADD_FLAG_PREPEND) != 0 ? 0 : -1)) {
219 ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
220 return 0;
221 }
222 if ((flags & X509_ADD_FLAG_UP_REF) != 0)
223 (void)X509_up_ref(cert);
224 return 1;
225 }
226
X509_add_certs(STACK_OF (X509)* sk,STACK_OF (X509)* certs,int flags)227 int X509_add_certs(STACK_OF(X509) *sk, STACK_OF(X509) *certs, int flags)
228 /* compiler would allow 'const' for the certs, yet they may get up-ref'ed */
229 {
230 if (sk == NULL) {
231 ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
232 return 0;
233 }
234 return ossl_x509_add_certs_new(&sk, certs, flags);
235 }
236
ossl_x509_add_certs_new(STACK_OF (X509)** p_sk,STACK_OF (X509)* certs,int flags)237 int ossl_x509_add_certs_new(STACK_OF(X509) **p_sk, STACK_OF(X509) *certs,
238 int flags)
239 /* compiler would allow 'const' for the certs, yet they may get up-ref'ed */
240 {
241 int n = sk_X509_num(certs /* may be NULL */);
242 int i;
243
244 for (i = 0; i < n; i++) {
245 int j = (flags & X509_ADD_FLAG_PREPEND) == 0 ? i : n - 1 - i;
246 /* if prepend, add certs in reverse order to keep original order */
247
248 if (!ossl_x509_add_cert_new(p_sk, sk_X509_value(certs, j), flags))
249 return 0;
250 }
251 return 1;
252 }
253
X509_NAME_cmp(const X509_NAME * a,const X509_NAME * b)254 int X509_NAME_cmp(const X509_NAME *a, const X509_NAME *b)
255 {
256 int ret;
257
258 if (b == NULL)
259 return a != NULL;
260 if (a == NULL)
261 return -1;
262
263 /* Ensure canonical encoding is present and up to date */
264 if (a->canon_enc == NULL || a->modified) {
265 ret = i2d_X509_NAME((X509_NAME *)a, NULL);
266 if (ret < 0)
267 return -2;
268 }
269
270 if (b->canon_enc == NULL || b->modified) {
271 ret = i2d_X509_NAME((X509_NAME *)b, NULL);
272 if (ret < 0)
273 return -2;
274 }
275
276 ret = a->canon_enclen - b->canon_enclen;
277 if (ret == 0 && a->canon_enclen == 0)
278 return 0;
279
280 if (a->canon_enc == NULL || b->canon_enc == NULL)
281 return -2;
282
283 if (ret == 0)
284 ret = memcmp(a->canon_enc, b->canon_enc, a->canon_enclen);
285
286 return ret < 0 ? -1 : ret > 0;
287 }
288
X509_NAME_hash_ex(const X509_NAME * x,OSSL_LIB_CTX * libctx,const char * propq,int * ok)289 unsigned long X509_NAME_hash_ex(const X509_NAME *x, OSSL_LIB_CTX *libctx,
290 const char *propq, int *ok)
291 {
292 unsigned long ret = 0;
293 unsigned char md[SHA_DIGEST_LENGTH];
294 EVP_MD *sha1 = EVP_MD_fetch(libctx, "SHA1", propq);
295
296 /* Make sure X509_NAME structure contains valid cached encoding */
297 i2d_X509_NAME(x, NULL);
298 if (ok != NULL)
299 *ok = 0;
300 if (sha1 != NULL
301 && EVP_Digest(x->canon_enc, x->canon_enclen, md, NULL, sha1, NULL)) {
302 ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
303 ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
304 ) & 0xffffffffL;
305 if (ok != NULL)
306 *ok = 1;
307 }
308 EVP_MD_free(sha1);
309 return ret;
310 }
311
312 #ifndef OPENSSL_NO_MD5
313 /*
314 * I now DER encode the name and hash it. Since I cache the DER encoding,
315 * this is reasonably efficient.
316 */
X509_NAME_hash_old(const X509_NAME * x)317 unsigned long X509_NAME_hash_old(const X509_NAME *x)
318 {
319 EVP_MD *md5 = EVP_MD_fetch(NULL, OSSL_DIGEST_NAME_MD5, "-fips");
320 EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
321 unsigned long ret = 0;
322 unsigned char md[16];
323
324 if (md5 == NULL || md_ctx == NULL)
325 goto end;
326
327 /* Make sure X509_NAME structure contains valid cached encoding */
328 i2d_X509_NAME(x, NULL);
329 if (EVP_DigestInit_ex(md_ctx, md5, NULL)
330 && EVP_DigestUpdate(md_ctx, x->bytes->data, x->bytes->length)
331 && EVP_DigestFinal_ex(md_ctx, md, NULL))
332 ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
333 ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
334 ) & 0xffffffffL;
335
336 end:
337 EVP_MD_CTX_free(md_ctx);
338 EVP_MD_free(md5);
339
340 return ret;
341 }
342 #endif
343
344 /* Search a stack of X509 for a match */
X509_find_by_issuer_and_serial(STACK_OF (X509)* sk,const X509_NAME * name,const ASN1_INTEGER * serial)345 X509 *X509_find_by_issuer_and_serial(STACK_OF(X509) *sk, const X509_NAME *name,
346 const ASN1_INTEGER *serial)
347 {
348 int i;
349 X509 x, *x509 = NULL;
350
351 if (!sk)
352 return NULL;
353
354 x.cert_info.serialNumber = *serial;
355 x.cert_info.issuer = (X509_NAME *)name; /* won't modify it */
356
357 for (i = 0; i < sk_X509_num(sk); i++) {
358 x509 = sk_X509_value(sk, i);
359 if (X509_issuer_and_serial_cmp(x509, &x) == 0)
360 return x509;
361 }
362 return NULL;
363 }
364
X509_find_by_subject(STACK_OF (X509)* sk,const X509_NAME * name)365 X509 *X509_find_by_subject(STACK_OF(X509) *sk, const X509_NAME *name)
366 {
367 X509 *x509;
368 int i;
369
370 for (i = 0; i < sk_X509_num(sk); i++) {
371 x509 = sk_X509_value(sk, i);
372 if (X509_NAME_cmp(X509_get_subject_name(x509), name) == 0)
373 return x509;
374 }
375 return NULL;
376 }
377
X509_get0_pubkey(const X509 * x)378 EVP_PKEY *X509_get0_pubkey(const X509 *x)
379 {
380 if (x == NULL)
381 return NULL;
382 return X509_PUBKEY_get0(x->cert_info.key);
383 }
384
X509_get_pubkey(X509 * x)385 EVP_PKEY *X509_get_pubkey(X509 *x)
386 {
387 if (x == NULL)
388 return NULL;
389 return X509_PUBKEY_get(x->cert_info.key);
390 }
391
X509_check_private_key(const X509 * cert,const EVP_PKEY * pkey)392 int X509_check_private_key(const X509 *cert, const EVP_PKEY *pkey)
393 {
394 const EVP_PKEY *xk = X509_get0_pubkey(cert);
395
396 if (xk == NULL) {
397 ERR_raise(ERR_LIB_X509, X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
398 return 0;
399 }
400 return ossl_x509_check_private_key(xk, pkey);
401 }
402
ossl_x509_check_private_key(const EVP_PKEY * x,const EVP_PKEY * pkey)403 int ossl_x509_check_private_key(const EVP_PKEY *x, const EVP_PKEY *pkey)
404 {
405 if (x == NULL) {
406 ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
407 return 0;
408 }
409 switch (EVP_PKEY_eq(x, pkey)) {
410 case 1:
411 return 1;
412 case 0:
413 ERR_raise(ERR_LIB_X509, X509_R_KEY_VALUES_MISMATCH);
414 return 0;
415 case -1:
416 ERR_raise(ERR_LIB_X509, X509_R_KEY_TYPE_MISMATCH);
417 return 0;
418 case -2:
419 ERR_raise(ERR_LIB_X509, X509_R_UNKNOWN_KEY_TYPE);
420 /* fall thru */
421 default:
422 return 0;
423 }
424 }
425
426 /*
427 * Check a suite B algorithm is permitted: pass in a public key and the NID
428 * of its signature (or 0 if no signature). The pflags is a pointer to a
429 * flags field which must contain the suite B verification flags.
430 */
431
432 #ifndef OPENSSL_NO_EC
433
check_suite_b(EVP_PKEY * pkey,int sign_nid,unsigned long * pflags)434 static int check_suite_b(EVP_PKEY *pkey, int sign_nid, unsigned long *pflags)
435 {
436 char curve_name[80];
437 size_t curve_name_len;
438 int curve_nid;
439
440 if (pkey == NULL || !EVP_PKEY_is_a(pkey, "EC"))
441 return X509_V_ERR_SUITE_B_INVALID_ALGORITHM;
442
443 if (!EVP_PKEY_get_group_name(pkey, curve_name, sizeof(curve_name),
444 &curve_name_len))
445 return X509_V_ERR_SUITE_B_INVALID_CURVE;
446
447 curve_nid = OBJ_txt2nid(curve_name);
448 /* Check curve is consistent with LOS */
449 if (curve_nid == NID_secp384r1) { /* P-384 */
450 /*
451 * Check signature algorithm is consistent with curve.
452 */
453 if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA384)
454 return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
455 if (!(*pflags & X509_V_FLAG_SUITEB_192_LOS))
456 return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
457 /* If we encounter P-384 we cannot use P-256 later */
458 *pflags &= ~X509_V_FLAG_SUITEB_128_LOS_ONLY;
459 } else if (curve_nid == NID_X9_62_prime256v1) { /* P-256 */
460 if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA256)
461 return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
462 if (!(*pflags & X509_V_FLAG_SUITEB_128_LOS_ONLY))
463 return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
464 } else {
465 return X509_V_ERR_SUITE_B_INVALID_CURVE;
466 }
467 return X509_V_OK;
468 }
469
X509_chain_check_suiteb(int * perror_depth,X509 * x,STACK_OF (X509)* chain,unsigned long flags)470 int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
471 unsigned long flags)
472 {
473 int rv, i, sign_nid;
474 EVP_PKEY *pk;
475 unsigned long tflags = flags;
476
477 if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
478 return X509_V_OK;
479
480 /* If no EE certificate passed in must be first in chain */
481 if (x == NULL) {
482 x = sk_X509_value(chain, 0);
483 i = 1;
484 } else {
485 i = 0;
486 }
487 pk = X509_get0_pubkey(x);
488
489 /*
490 * With DANE-EE(3) success, or DANE-EE(3)/PKIX-EE(1) failure we don't build
491 * a chain all, just report trust success or failure, but must also report
492 * Suite-B errors if applicable. This is indicated via a NULL chain
493 * pointer. All we need to do is check the leaf key algorithm.
494 */
495 if (chain == NULL)
496 return check_suite_b(pk, -1, &tflags);
497
498 if (X509_get_version(x) != X509_VERSION_3) {
499 rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
500 /* Correct error depth */
501 i = 0;
502 goto end;
503 }
504
505 /* Check EE key only */
506 rv = check_suite_b(pk, -1, &tflags);
507 if (rv != X509_V_OK) {
508 /* Correct error depth */
509 i = 0;
510 goto end;
511 }
512 for (; i < sk_X509_num(chain); i++) {
513 sign_nid = X509_get_signature_nid(x);
514 x = sk_X509_value(chain, i);
515 if (X509_get_version(x) != X509_VERSION_3) {
516 rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
517 goto end;
518 }
519 pk = X509_get0_pubkey(x);
520 rv = check_suite_b(pk, sign_nid, &tflags);
521 if (rv != X509_V_OK)
522 goto end;
523 }
524
525 /* Final check: root CA signature */
526 rv = check_suite_b(pk, X509_get_signature_nid(x), &tflags);
527 end:
528 if (rv != X509_V_OK) {
529 /* Invalid signature or LOS errors are for previous cert */
530 if ((rv == X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM
531 || rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED) && i)
532 i--;
533 /*
534 * If we have LOS error and flags changed then we are signing P-384
535 * with P-256. Use more meaningful error.
536 */
537 if (rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED && flags != tflags)
538 rv = X509_V_ERR_SUITE_B_CANNOT_SIGN_P_384_WITH_P_256;
539 if (perror_depth)
540 *perror_depth = i;
541 }
542 return rv;
543 }
544
X509_CRL_check_suiteb(X509_CRL * crl,EVP_PKEY * pk,unsigned long flags)545 int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
546 {
547 int sign_nid;
548 if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
549 return X509_V_OK;
550 sign_nid = OBJ_obj2nid(crl->crl.sig_alg.algorithm);
551 return check_suite_b(pk, sign_nid, &flags);
552 }
553
554 #else
X509_chain_check_suiteb(int * perror_depth,X509 * x,STACK_OF (X509)* chain,unsigned long flags)555 int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
556 unsigned long flags)
557 {
558 return 0;
559 }
560
X509_CRL_check_suiteb(X509_CRL * crl,EVP_PKEY * pk,unsigned long flags)561 int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
562 {
563 return 0;
564 }
565
566 #endif
567
568 /*
569 * Not strictly speaking an "up_ref" as a STACK doesn't have a reference
570 * count but it has the same effect by duping the STACK and upping the ref of
571 * each X509 structure.
572 */
STACK_OF(X509)573 STACK_OF(X509) *X509_chain_up_ref(STACK_OF(X509) *chain)
574 {
575 STACK_OF(X509) *ret = sk_X509_dup(chain);
576 int i;
577
578 if (ret == NULL)
579 return NULL;
580 for (i = 0; i < sk_X509_num(ret); i++) {
581 X509 *x = sk_X509_value(ret, i);
582
583 if (!X509_up_ref(x))
584 goto err;
585 }
586 return ret;
587
588 err:
589 while (i-- > 0)
590 X509_free(sk_X509_value(ret, i));
591 sk_X509_free(ret);
592 return NULL;
593 }
594