xref: /openbsd-src/lib/libcrypto/x509/x509_vfy.c (revision 8500990981f885cbe5e6a4958549cacc238b5ae6)
1 /* crypto/x509/x509_vfy.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 
59 #include <stdio.h>
60 #include <time.h>
61 #include <errno.h>
62 
63 #include "cryptlib.h"
64 #include <openssl/crypto.h>
65 #include <openssl/lhash.h>
66 #include <openssl/buffer.h>
67 #include <openssl/evp.h>
68 #include <openssl/asn1.h>
69 #include <openssl/x509.h>
70 #include <openssl/x509v3.h>
71 #include <openssl/objects.h>
72 
73 static int null_callback(int ok,X509_STORE_CTX *e);
74 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer);
75 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x);
76 static int check_chain_purpose(X509_STORE_CTX *ctx);
77 static int check_trust(X509_STORE_CTX *ctx);
78 static int check_revocation(X509_STORE_CTX *ctx);
79 static int check_cert(X509_STORE_CTX *ctx);
80 static int internal_verify(X509_STORE_CTX *ctx);
81 const char *X509_version="X.509" OPENSSL_VERSION_PTEXT;
82 
83 
84 static int null_callback(int ok, X509_STORE_CTX *e)
85 	{
86 	return ok;
87 	}
88 
89 #if 0
90 static int x509_subject_cmp(X509 **a, X509 **b)
91 	{
92 	return X509_subject_name_cmp(*a,*b);
93 	}
94 #endif
95 
96 int X509_verify_cert(X509_STORE_CTX *ctx)
97 	{
98 	X509 *x,*xtmp,*chain_ss=NULL;
99 	X509_NAME *xn;
100 	int depth,i,ok=0;
101 	int num;
102 	int (*cb)();
103 	STACK_OF(X509) *sktmp=NULL;
104 
105 	if (ctx->cert == NULL)
106 		{
107 		X509err(X509_F_X509_VERIFY_CERT,X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
108 		return -1;
109 		}
110 
111 	cb=ctx->verify_cb;
112 
113 	/* first we make sure the chain we are going to build is
114 	 * present and that the first entry is in place */
115 	if (ctx->chain == NULL)
116 		{
117 		if (	((ctx->chain=sk_X509_new_null()) == NULL) ||
118 			(!sk_X509_push(ctx->chain,ctx->cert)))
119 			{
120 			X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
121 			goto end;
122 			}
123 		CRYPTO_add(&ctx->cert->references,1,CRYPTO_LOCK_X509);
124 		ctx->last_untrusted=1;
125 		}
126 
127 	/* We use a temporary STACK so we can chop and hack at it */
128 	if (ctx->untrusted != NULL
129 	    && (sktmp=sk_X509_dup(ctx->untrusted)) == NULL)
130 		{
131 		X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
132 		goto end;
133 		}
134 
135 	num=sk_X509_num(ctx->chain);
136 	x=sk_X509_value(ctx->chain,num-1);
137 	depth=ctx->depth;
138 
139 
140 	for (;;)
141 		{
142 		/* If we have enough, we break */
143 		if (depth < num) break; /* FIXME: If this happens, we should take
144 		                         * note of it and, if appropriate, use the
145 		                         * X509_V_ERR_CERT_CHAIN_TOO_LONG error
146 		                         * code later.
147 		                         */
148 
149 		/* If we are self signed, we break */
150 		xn=X509_get_issuer_name(x);
151 		if (ctx->check_issued(ctx, x,x)) break;
152 
153 		/* If we were passed a cert chain, use it first */
154 		if (ctx->untrusted != NULL)
155 			{
156 			xtmp=find_issuer(ctx, sktmp,x);
157 			if (xtmp != NULL)
158 				{
159 				if (!sk_X509_push(ctx->chain,xtmp))
160 					{
161 					X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
162 					goto end;
163 					}
164 				CRYPTO_add(&xtmp->references,1,CRYPTO_LOCK_X509);
165 				sk_X509_delete_ptr(sktmp,xtmp);
166 				ctx->last_untrusted++;
167 				x=xtmp;
168 				num++;
169 				/* reparse the full chain for
170 				 * the next one */
171 				continue;
172 				}
173 			}
174 		break;
175 		}
176 
177 	/* at this point, chain should contain a list of untrusted
178 	 * certificates.  We now need to add at least one trusted one,
179 	 * if possible, otherwise we complain. */
180 
181 	/* Examine last certificate in chain and see if it
182  	 * is self signed.
183  	 */
184 
185 	i=sk_X509_num(ctx->chain);
186 	x=sk_X509_value(ctx->chain,i-1);
187 	xn = X509_get_subject_name(x);
188 	if (ctx->check_issued(ctx, x, x))
189 		{
190 		/* we have a self signed certificate */
191 		if (sk_X509_num(ctx->chain) == 1)
192 			{
193 			/* We have a single self signed certificate: see if
194 			 * we can find it in the store. We must have an exact
195 			 * match to avoid possible impersonation.
196 			 */
197 			ok = ctx->get_issuer(&xtmp, ctx, x);
198 			if ((ok <= 0) || X509_cmp(x, xtmp))
199 				{
200 				ctx->error=X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT;
201 				ctx->current_cert=x;
202 				ctx->error_depth=i-1;
203 				if (ok == 1) X509_free(xtmp);
204 				ok=cb(0,ctx);
205 				if (!ok) goto end;
206 				}
207 			else
208 				{
209 				/* We have a match: replace certificate with store version
210 				 * so we get any trust settings.
211 				 */
212 				X509_free(x);
213 				x = xtmp;
214 				sk_X509_set(ctx->chain, i - 1, x);
215 				ctx->last_untrusted=0;
216 				}
217 			}
218 		else
219 			{
220 			/* extract and save self signed certificate for later use */
221 			chain_ss=sk_X509_pop(ctx->chain);
222 			ctx->last_untrusted--;
223 			num--;
224 			x=sk_X509_value(ctx->chain,num-1);
225 			}
226 		}
227 
228 	/* We now lookup certs from the certificate store */
229 	for (;;)
230 		{
231 		/* If we have enough, we break */
232 		if (depth < num) break;
233 
234 		/* If we are self signed, we break */
235 		xn=X509_get_issuer_name(x);
236 		if (ctx->check_issued(ctx,x,x)) break;
237 
238 		ok = ctx->get_issuer(&xtmp, ctx, x);
239 
240 		if (ok < 0) return ok;
241 		if (ok == 0) break;
242 
243 		x = xtmp;
244 		if (!sk_X509_push(ctx->chain,x))
245 			{
246 			X509_free(xtmp);
247 			X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
248 			return 0;
249 			}
250 		num++;
251 		}
252 
253 	/* we now have our chain, lets check it... */
254 	xn=X509_get_issuer_name(x);
255 
256 	/* Is last certificate looked up self signed? */
257 	if (!ctx->check_issued(ctx,x,x))
258 		{
259 		if ((chain_ss == NULL) || !ctx->check_issued(ctx, x, chain_ss))
260 			{
261 			if (ctx->last_untrusted >= num)
262 				ctx->error=X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY;
263 			else
264 				ctx->error=X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT;
265 			ctx->current_cert=x;
266 			}
267 		else
268 			{
269 
270 			sk_X509_push(ctx->chain,chain_ss);
271 			num++;
272 			ctx->last_untrusted=num;
273 			ctx->current_cert=chain_ss;
274 			ctx->error=X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN;
275 			chain_ss=NULL;
276 			}
277 
278 		ctx->error_depth=num-1;
279 		ok=cb(0,ctx);
280 		if (!ok) goto end;
281 		}
282 
283 	/* We have the chain complete: now we need to check its purpose */
284 	if (ctx->purpose > 0) ok = check_chain_purpose(ctx);
285 
286 	if (!ok) goto end;
287 
288 	/* The chain extensions are OK: check trust */
289 
290 	if (ctx->trust > 0) ok = check_trust(ctx);
291 
292 	if (!ok) goto end;
293 
294 	/* We may as well copy down any DSA parameters that are required */
295 	X509_get_pubkey_parameters(NULL,ctx->chain);
296 
297 	/* Check revocation status: we do this after copying parameters
298 	 * because they may be needed for CRL signature verification.
299 	 */
300 
301 	ok = ctx->check_revocation(ctx);
302 	if(!ok) goto end;
303 
304 	/* At this point, we have a chain and just need to verify it */
305 	if (ctx->verify != NULL)
306 		ok=ctx->verify(ctx);
307 	else
308 		ok=internal_verify(ctx);
309 	if (0)
310 		{
311 end:
312 		X509_get_pubkey_parameters(NULL,ctx->chain);
313 		}
314 	if (sktmp != NULL) sk_X509_free(sktmp);
315 	if (chain_ss != NULL) X509_free(chain_ss);
316 	return ok;
317 	}
318 
319 
320 /* Given a STACK_OF(X509) find the issuer of cert (if any)
321  */
322 
323 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)
324 {
325 	int i;
326 	X509 *issuer;
327 	for (i = 0; i < sk_X509_num(sk); i++)
328 		{
329 		issuer = sk_X509_value(sk, i);
330 		if (ctx->check_issued(ctx, x, issuer))
331 			return issuer;
332 		}
333 	return NULL;
334 }
335 
336 /* Given a possible certificate and issuer check them */
337 
338 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)
339 {
340 	int ret;
341 	ret = X509_check_issued(issuer, x);
342 	if (ret == X509_V_OK)
343 		return 1;
344 	/* If we haven't asked for issuer errors don't set ctx */
345 	if (!(ctx->flags & X509_V_FLAG_CB_ISSUER_CHECK))
346 		return 0;
347 
348 	ctx->error = ret;
349 	ctx->current_cert = x;
350 	ctx->current_issuer = issuer;
351 	return ctx->verify_cb(0, ctx);
352 	return 0;
353 }
354 
355 /* Alternative lookup method: look from a STACK stored in other_ctx */
356 
357 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)
358 {
359 	*issuer = find_issuer(ctx, ctx->other_ctx, x);
360 	if (*issuer)
361 		{
362 		CRYPTO_add(&(*issuer)->references,1,CRYPTO_LOCK_X509);
363 		return 1;
364 		}
365 	else
366 		return 0;
367 }
368 
369 
370 /* Check a certificate chains extensions for consistency
371  * with the supplied purpose
372  */
373 
374 static int check_chain_purpose(X509_STORE_CTX *ctx)
375 {
376 #ifdef OPENSSL_NO_CHAIN_VERIFY
377 	return 1;
378 #else
379 	int i, ok=0;
380 	X509 *x;
381 	int (*cb)();
382 	cb=ctx->verify_cb;
383 	/* Check all untrusted certificates */
384 	for (i = 0; i < ctx->last_untrusted; i++)
385 		{
386 		x = sk_X509_value(ctx->chain, i);
387 		if (!(ctx->flags & X509_V_FLAG_IGNORE_CRITICAL)
388 			&& (x->ex_flags & EXFLAG_CRITICAL))
389 			{
390 			ctx->error = X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION;
391 			ctx->error_depth = i;
392 			ctx->current_cert = x;
393 			ok=cb(0,ctx);
394 			if (!ok) goto end;
395 			}
396 		if (!X509_check_purpose(x, ctx->purpose, i))
397 			{
398 			if (i)
399 				ctx->error = X509_V_ERR_INVALID_CA;
400 			else
401 				ctx->error = X509_V_ERR_INVALID_PURPOSE;
402 			ctx->error_depth = i;
403 			ctx->current_cert = x;
404 			ok=cb(0,ctx);
405 			if (!ok) goto end;
406 			}
407 		/* Check pathlen */
408 		if ((i > 1) && (x->ex_pathlen != -1)
409 			   && (i > (x->ex_pathlen + 1)))
410 			{
411 			ctx->error = X509_V_ERR_PATH_LENGTH_EXCEEDED;
412 			ctx->error_depth = i;
413 			ctx->current_cert = x;
414 			ok=cb(0,ctx);
415 			if (!ok) goto end;
416 			}
417 		}
418 	ok = 1;
419  end:
420 	return ok;
421 #endif
422 }
423 
424 static int check_trust(X509_STORE_CTX *ctx)
425 {
426 #ifdef OPENSSL_NO_CHAIN_VERIFY
427 	return 1;
428 #else
429 	int i, ok;
430 	X509 *x;
431 	int (*cb)();
432 	cb=ctx->verify_cb;
433 /* For now just check the last certificate in the chain */
434 	i = sk_X509_num(ctx->chain) - 1;
435 	x = sk_X509_value(ctx->chain, i);
436 	ok = X509_check_trust(x, ctx->trust, 0);
437 	if (ok == X509_TRUST_TRUSTED)
438 		return 1;
439 	ctx->error_depth = i;
440 	ctx->current_cert = x;
441 	if (ok == X509_TRUST_REJECTED)
442 		ctx->error = X509_V_ERR_CERT_REJECTED;
443 	else
444 		ctx->error = X509_V_ERR_CERT_UNTRUSTED;
445 	ok = cb(0, ctx);
446 	return ok;
447 #endif
448 }
449 
450 static int check_revocation(X509_STORE_CTX *ctx)
451 	{
452 	int i, last, ok;
453 	if (!(ctx->flags & X509_V_FLAG_CRL_CHECK))
454 		return 1;
455 	if (ctx->flags & X509_V_FLAG_CRL_CHECK_ALL)
456 		last = sk_X509_num(ctx->chain) - 1;
457 	else
458 		last = 0;
459 	for(i = 0; i <= last; i++)
460 		{
461 		ctx->error_depth = i;
462 		ok = check_cert(ctx);
463 		if (!ok) return ok;
464 		}
465 	return 1;
466 	}
467 
468 static int check_cert(X509_STORE_CTX *ctx)
469 	{
470 	X509_CRL *crl = NULL;
471 	X509 *x;
472 	int ok, cnum;
473 	cnum = ctx->error_depth;
474 	x = sk_X509_value(ctx->chain, cnum);
475 	ctx->current_cert = x;
476 	/* Try to retrieve relevant CRL */
477 	ok = ctx->get_crl(ctx, &crl, x);
478 	/* If error looking up CRL, nothing we can do except
479 	 * notify callback
480 	 */
481 	if(!ok)
482 		{
483 		ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL;
484 		ok = ctx->verify_cb(0, ctx);
485 		goto err;
486 		}
487 	ctx->current_crl = crl;
488 	ok = ctx->check_crl(ctx, crl);
489 	if (!ok) goto err;
490 	ok = ctx->cert_crl(ctx, crl, x);
491 	err:
492 	ctx->current_crl = NULL;
493 	X509_CRL_free(crl);
494 	return ok;
495 
496 	}
497 
498 /* Retrieve CRL corresponding to certificate: currently just a
499  * subject lookup: maybe use AKID later...
500  * Also might look up any included CRLs too (e.g PKCS#7 signedData).
501  */
502 static int get_crl(X509_STORE_CTX *ctx, X509_CRL **crl, X509 *x)
503 	{
504 	int ok;
505 	X509_OBJECT xobj;
506 	ok = X509_STORE_get_by_subject(ctx, X509_LU_CRL, X509_get_issuer_name(x), &xobj);
507 	if (!ok) return 0;
508 	*crl = xobj.data.crl;
509 	return 1;
510 	}
511 
512 /* Check CRL validity */
513 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)
514 	{
515 	X509 *issuer = NULL;
516 	EVP_PKEY *ikey = NULL;
517 	int ok = 0, chnum, cnum, i;
518 	time_t *ptime;
519 	cnum = ctx->error_depth;
520 	chnum = sk_X509_num(ctx->chain) - 1;
521 	/* Find CRL issuer: if not last certificate then issuer
522 	 * is next certificate in chain.
523 	 */
524 	if(cnum < chnum)
525 		issuer = sk_X509_value(ctx->chain, cnum + 1);
526 	else
527 		{
528 		issuer = sk_X509_value(ctx->chain, chnum);
529 		/* If not self signed, can't check signature */
530 		if(!ctx->check_issued(ctx, issuer, issuer))
531 			{
532 			ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER;
533 			ok = ctx->verify_cb(0, ctx);
534 			if(!ok) goto err;
535 			}
536 		}
537 
538 	if(issuer)
539 		{
540 
541 		/* Attempt to get issuer certificate public key */
542 		ikey = X509_get_pubkey(issuer);
543 
544 		if(!ikey)
545 			{
546 			ctx->error=X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
547 			ok = ctx->verify_cb(0, ctx);
548 			if (!ok) goto err;
549 			}
550 		else
551 			{
552 			/* Verify CRL signature */
553 			if(X509_CRL_verify(crl, ikey) <= 0)
554 				{
555 				ctx->error=X509_V_ERR_CRL_SIGNATURE_FAILURE;
556 				ok = ctx->verify_cb(0, ctx);
557 				if (!ok) goto err;
558 				}
559 			}
560 		}
561 
562 	/* OK, CRL signature valid check times */
563 	if (ctx->flags & X509_V_FLAG_USE_CHECK_TIME)
564 		ptime = &ctx->check_time;
565 	else
566 		ptime = NULL;
567 
568 	i=X509_cmp_time(X509_CRL_get_lastUpdate(crl), ptime);
569 	if (i == 0)
570 		{
571 		ctx->error=X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD;
572 		ok = ctx->verify_cb(0, ctx);
573 		if (!ok) goto err;
574 		}
575 
576 	if (i > 0)
577 		{
578 		ctx->error=X509_V_ERR_CRL_NOT_YET_VALID;
579 		ok = ctx->verify_cb(0, ctx);
580 		if (!ok) goto err;
581 		}
582 
583 	if(X509_CRL_get_nextUpdate(crl))
584 		{
585 		i=X509_cmp_time(X509_CRL_get_nextUpdate(crl), ptime);
586 
587 		if (i == 0)
588 			{
589 			ctx->error=X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD;
590 			ok = ctx->verify_cb(0, ctx);
591 			if (!ok) goto err;
592 			}
593 
594 		if (i < 0)
595 			{
596 			ctx->error=X509_V_ERR_CRL_HAS_EXPIRED;
597 			ok = ctx->verify_cb(0, ctx);
598 			if (!ok) goto err;
599 			}
600 		}
601 
602 	ok = 1;
603 
604 	err:
605 	EVP_PKEY_free(ikey);
606 	return ok;
607 	}
608 
609 /* Check certificate against CRL */
610 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)
611 	{
612 	int idx, ok;
613 	X509_REVOKED rtmp;
614 	/* Look for serial number of certificate in CRL */
615 	rtmp.serialNumber = X509_get_serialNumber(x);
616 	idx = sk_X509_REVOKED_find(crl->crl->revoked, &rtmp);
617 	/* Not found: OK */
618 	if(idx == -1) return 1;
619 	/* Otherwise revoked: want something cleverer than
620 	 * this to handle entry extensions in V2 CRLs.
621 	 */
622 	ctx->error = X509_V_ERR_CERT_REVOKED;
623 	ok = ctx->verify_cb(0, ctx);
624 	return ok;
625 	}
626 
627 static int internal_verify(X509_STORE_CTX *ctx)
628 	{
629 	int i,ok=0,n;
630 	X509 *xs,*xi;
631 	EVP_PKEY *pkey=NULL;
632 	time_t *ptime;
633 	int (*cb)();
634 
635 	cb=ctx->verify_cb;
636 
637 	n=sk_X509_num(ctx->chain);
638 	ctx->error_depth=n-1;
639 	n--;
640 	xi=sk_X509_value(ctx->chain,n);
641 	if (ctx->flags & X509_V_FLAG_USE_CHECK_TIME)
642 		ptime = &ctx->check_time;
643 	else
644 		ptime = NULL;
645 	if (ctx->check_issued(ctx, xi, xi))
646 		xs=xi;
647 	else
648 		{
649 		if (n <= 0)
650 			{
651 			ctx->error=X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE;
652 			ctx->current_cert=xi;
653 			ok=cb(0,ctx);
654 			goto end;
655 			}
656 		else
657 			{
658 			n--;
659 			ctx->error_depth=n;
660 			xs=sk_X509_value(ctx->chain,n);
661 			}
662 		}
663 
664 /*	ctx->error=0;  not needed */
665 	while (n >= 0)
666 		{
667 		ctx->error_depth=n;
668 		if (!xs->valid)
669 			{
670 			if ((pkey=X509_get_pubkey(xi)) == NULL)
671 				{
672 				ctx->error=X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
673 				ctx->current_cert=xi;
674 				ok=(*cb)(0,ctx);
675 				if (!ok) goto end;
676 				}
677 			else if (X509_verify(xs,pkey) <= 0)
678 				/* XXX  For the final trusted self-signed cert,
679 				 * this is a waste of time.  That check should
680 				 * optional so that e.g. 'openssl x509' can be
681 				 * used to detect invalid self-signatures, but
682 				 * we don't verify again and again in SSL
683 				 * handshakes and the like once the cert has
684 				 * been declared trusted. */
685 				{
686 				ctx->error=X509_V_ERR_CERT_SIGNATURE_FAILURE;
687 				ctx->current_cert=xs;
688 				ok=(*cb)(0,ctx);
689 				if (!ok)
690 					{
691 					EVP_PKEY_free(pkey);
692 					goto end;
693 					}
694 				}
695 			EVP_PKEY_free(pkey);
696 			pkey=NULL;
697 
698 			i=X509_cmp_time(X509_get_notBefore(xs), ptime);
699 			if (i == 0)
700 				{
701 				ctx->error=X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD;
702 				ctx->current_cert=xs;
703 				ok=(*cb)(0,ctx);
704 				if (!ok) goto end;
705 				}
706 			if (i > 0)
707 				{
708 				ctx->error=X509_V_ERR_CERT_NOT_YET_VALID;
709 				ctx->current_cert=xs;
710 				ok=(*cb)(0,ctx);
711 				if (!ok) goto end;
712 				}
713 			xs->valid=1;
714 			}
715 
716 		i=X509_cmp_time(X509_get_notAfter(xs), ptime);
717 		if (i == 0)
718 			{
719 			ctx->error=X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD;
720 			ctx->current_cert=xs;
721 			ok=(*cb)(0,ctx);
722 			if (!ok) goto end;
723 			}
724 
725 		if (i < 0)
726 			{
727 			ctx->error=X509_V_ERR_CERT_HAS_EXPIRED;
728 			ctx->current_cert=xs;
729 			ok=(*cb)(0,ctx);
730 			if (!ok) goto end;
731 			}
732 
733 		/* The last error (if any) is still in the error value */
734 		ctx->current_cert=xs;
735 		ok=(*cb)(1,ctx);
736 		if (!ok) goto end;
737 
738 		n--;
739 		if (n >= 0)
740 			{
741 			xi=xs;
742 			xs=sk_X509_value(ctx->chain,n);
743 			}
744 		}
745 	ok=1;
746 end:
747 	return ok;
748 	}
749 
750 int X509_cmp_current_time(ASN1_TIME *ctm)
751 {
752 	return X509_cmp_time(ctm, NULL);
753 }
754 
755 int X509_cmp_time(ASN1_TIME *ctm, time_t *cmp_time)
756 	{
757 	char *str;
758 	ASN1_TIME atm;
759 	long offset;
760 	char buff1[24],buff2[24],*p;
761 	int i,j;
762 
763 	p=buff1;
764 	i=ctm->length;
765 	str=(char *)ctm->data;
766 	if (ctm->type == V_ASN1_UTCTIME)
767 		{
768 		if ((i < 11) || (i > 17)) return 0;
769 		memcpy(p,str,10);
770 		p+=10;
771 		str+=10;
772 		}
773 	else
774 		{
775 		if (i < 13) return 0;
776 		memcpy(p,str,12);
777 		p+=12;
778 		str+=12;
779 		}
780 
781 	if ((*str == 'Z') || (*str == '-') || (*str == '+'))
782 		{ *(p++)='0'; *(p++)='0'; }
783 	else
784 		{
785 		*(p++)= *(str++);
786 		*(p++)= *(str++);
787 		/* Skip any fractional seconds... */
788 		if (*str == '.')
789 			{
790 			str++;
791 			while ((*str >= '0') && (*str <= '9')) str++;
792 			}
793 
794 		}
795 	*(p++)='Z';
796 	*(p++)='\0';
797 
798 	if (*str == 'Z')
799 		offset=0;
800 	else
801 		{
802 		if ((*str != '+') && (str[5] != '-'))
803 			return 0;
804 		offset=((str[1]-'0')*10+(str[2]-'0'))*60;
805 		offset+=(str[3]-'0')*10+(str[4]-'0');
806 		if (*str == '-')
807 			offset= -offset;
808 		}
809 	atm.type=ctm->type;
810 	atm.length=sizeof(buff2);
811 	atm.data=(unsigned char *)buff2;
812 
813 	X509_time_adj(&atm,-offset*60, cmp_time);
814 
815 	if (ctm->type == V_ASN1_UTCTIME)
816 		{
817 		i=(buff1[0]-'0')*10+(buff1[1]-'0');
818 		if (i < 50) i+=100; /* cf. RFC 2459 */
819 		j=(buff2[0]-'0')*10+(buff2[1]-'0');
820 		if (j < 50) j+=100;
821 
822 		if (i < j) return -1;
823 		if (i > j) return 1;
824 		}
825 	i=strcmp(buff1,buff2);
826 	if (i == 0) /* wait a second then return younger :-) */
827 		return -1;
828 	else
829 		return i;
830 	}
831 
832 ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)
833 {
834 	return X509_time_adj(s, adj, NULL);
835 }
836 
837 ASN1_TIME *X509_time_adj(ASN1_TIME *s, long adj, time_t *in_tm)
838 	{
839 	time_t t;
840 	int type = -1;
841 
842 	if (in_tm) t = *in_tm;
843 	else time(&t);
844 
845 	t+=adj;
846 	if (s) type = s->type;
847 	if (type == V_ASN1_UTCTIME) return ASN1_UTCTIME_set(s,t);
848 	if (type == V_ASN1_GENERALIZEDTIME) return ASN1_GENERALIZEDTIME_set(s, t);
849 	return ASN1_TIME_set(s, t);
850 	}
851 
852 int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
853 	{
854 	EVP_PKEY *ktmp=NULL,*ktmp2;
855 	int i,j;
856 
857 	if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey)) return 1;
858 
859 	for (i=0; i<sk_X509_num(chain); i++)
860 		{
861 		ktmp=X509_get_pubkey(sk_X509_value(chain,i));
862 		if (ktmp == NULL)
863 			{
864 			X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
865 			return 0;
866 			}
867 		if (!EVP_PKEY_missing_parameters(ktmp))
868 			break;
869 		else
870 			{
871 			EVP_PKEY_free(ktmp);
872 			ktmp=NULL;
873 			}
874 		}
875 	if (ktmp == NULL)
876 		{
877 		X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
878 		return 0;
879 		}
880 
881 	/* first, populate the other certs */
882 	for (j=i-1; j >= 0; j--)
883 		{
884 		ktmp2=X509_get_pubkey(sk_X509_value(chain,j));
885 		EVP_PKEY_copy_parameters(ktmp2,ktmp);
886 		EVP_PKEY_free(ktmp2);
887 		}
888 
889 	if (pkey != NULL) EVP_PKEY_copy_parameters(pkey,ktmp);
890 	EVP_PKEY_free(ktmp);
891 	return 1;
892 	}
893 
894 int X509_STORE_CTX_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
895 	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
896 	{
897 	/* This function is (usually) called only once, by
898 	 * SSL_get_ex_data_X509_STORE_CTX_idx (ssl/ssl_cert.c). */
899 	return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_X509_STORE_CTX, argl, argp,
900 			new_func, dup_func, free_func);
901 	}
902 
903 int X509_STORE_CTX_set_ex_data(X509_STORE_CTX *ctx, int idx, void *data)
904 	{
905 	return CRYPTO_set_ex_data(&ctx->ex_data,idx,data);
906 	}
907 
908 void *X509_STORE_CTX_get_ex_data(X509_STORE_CTX *ctx, int idx)
909 	{
910 	return CRYPTO_get_ex_data(&ctx->ex_data,idx);
911 	}
912 
913 int X509_STORE_CTX_get_error(X509_STORE_CTX *ctx)
914 	{
915 	return ctx->error;
916 	}
917 
918 void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int err)
919 	{
920 	ctx->error=err;
921 	}
922 
923 int X509_STORE_CTX_get_error_depth(X509_STORE_CTX *ctx)
924 	{
925 	return ctx->error_depth;
926 	}
927 
928 X509 *X509_STORE_CTX_get_current_cert(X509_STORE_CTX *ctx)
929 	{
930 	return ctx->current_cert;
931 	}
932 
933 STACK_OF(X509) *X509_STORE_CTX_get_chain(X509_STORE_CTX *ctx)
934 	{
935 	return ctx->chain;
936 	}
937 
938 STACK_OF(X509) *X509_STORE_CTX_get1_chain(X509_STORE_CTX *ctx)
939 	{
940 	int i;
941 	X509 *x;
942 	STACK_OF(X509) *chain;
943 	if (!ctx->chain || !(chain = sk_X509_dup(ctx->chain))) return NULL;
944 	for (i = 0; i < sk_X509_num(chain); i++)
945 		{
946 		x = sk_X509_value(chain, i);
947 		CRYPTO_add(&x->references, 1, CRYPTO_LOCK_X509);
948 		}
949 	return chain;
950 	}
951 
952 void X509_STORE_CTX_set_cert(X509_STORE_CTX *ctx, X509 *x)
953 	{
954 	ctx->cert=x;
955 	}
956 
957 void X509_STORE_CTX_set_chain(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
958 	{
959 	ctx->untrusted=sk;
960 	}
961 
962 int X509_STORE_CTX_set_purpose(X509_STORE_CTX *ctx, int purpose)
963 	{
964 	return X509_STORE_CTX_purpose_inherit(ctx, 0, purpose, 0);
965 	}
966 
967 int X509_STORE_CTX_set_trust(X509_STORE_CTX *ctx, int trust)
968 	{
969 	return X509_STORE_CTX_purpose_inherit(ctx, 0, 0, trust);
970 	}
971 
972 /* This function is used to set the X509_STORE_CTX purpose and trust
973  * values. This is intended to be used when another structure has its
974  * own trust and purpose values which (if set) will be inherited by
975  * the ctx. If they aren't set then we will usually have a default
976  * purpose in mind which should then be used to set the trust value.
977  * An example of this is SSL use: an SSL structure will have its own
978  * purpose and trust settings which the application can set: if they
979  * aren't set then we use the default of SSL client/server.
980  */
981 
982 int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
983 				int purpose, int trust)
984 {
985 	int idx;
986 	/* If purpose not set use default */
987 	if (!purpose) purpose = def_purpose;
988 	/* If we have a purpose then check it is valid */
989 	if (purpose)
990 		{
991 		X509_PURPOSE *ptmp;
992 		idx = X509_PURPOSE_get_by_id(purpose);
993 		if (idx == -1)
994 			{
995 			X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
996 						X509_R_UNKNOWN_PURPOSE_ID);
997 			return 0;
998 			}
999 		ptmp = X509_PURPOSE_get0(idx);
1000 		if (ptmp->trust == X509_TRUST_DEFAULT)
1001 			{
1002 			idx = X509_PURPOSE_get_by_id(def_purpose);
1003 			if (idx == -1)
1004 				{
1005 				X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
1006 						X509_R_UNKNOWN_PURPOSE_ID);
1007 				return 0;
1008 				}
1009 			ptmp = X509_PURPOSE_get0(idx);
1010 			}
1011 		/* If trust not set then get from purpose default */
1012 		if (!trust) trust = ptmp->trust;
1013 		}
1014 	if (trust)
1015 		{
1016 		idx = X509_TRUST_get_by_id(trust);
1017 		if (idx == -1)
1018 			{
1019 			X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
1020 						X509_R_UNKNOWN_TRUST_ID);
1021 			return 0;
1022 			}
1023 		}
1024 
1025 	if (purpose && !ctx->purpose) ctx->purpose = purpose;
1026 	if (trust && !ctx->trust) ctx->trust = trust;
1027 	return 1;
1028 }
1029 
1030 X509_STORE_CTX *X509_STORE_CTX_new(void)
1031 {
1032 	X509_STORE_CTX *ctx;
1033 	ctx = (X509_STORE_CTX *)OPENSSL_malloc(sizeof(X509_STORE_CTX));
1034 	if (!ctx)
1035 		{
1036 		X509err(X509_F_X509_STORE_CTX_NEW,ERR_R_MALLOC_FAILURE);
1037 		return NULL;
1038 		}
1039 	memset(ctx, 0, sizeof(X509_STORE_CTX));
1040 	return ctx;
1041 }
1042 
1043 void X509_STORE_CTX_free(X509_STORE_CTX *ctx)
1044 {
1045 	X509_STORE_CTX_cleanup(ctx);
1046 	OPENSSL_free(ctx);
1047 }
1048 
1049 int X509_STORE_CTX_init(X509_STORE_CTX *ctx, X509_STORE *store, X509 *x509,
1050 	     STACK_OF(X509) *chain)
1051 	{
1052 	ctx->ctx=store;
1053 	ctx->current_method=0;
1054 	ctx->cert=x509;
1055 	ctx->untrusted=chain;
1056 	ctx->last_untrusted=0;
1057 	ctx->check_time=0;
1058 	ctx->other_ctx=NULL;
1059 	ctx->valid=0;
1060 	ctx->chain=NULL;
1061 	ctx->depth=9;
1062 	ctx->error=0;
1063 	ctx->error_depth=0;
1064 	ctx->current_cert=NULL;
1065 	ctx->current_issuer=NULL;
1066 
1067 	/* Inherit callbacks and flags from X509_STORE if not set
1068 	 * use defaults.
1069 	 */
1070 
1071 
1072 	if (store)
1073 		{
1074 		ctx->purpose=store->purpose;
1075 		ctx->trust=store->trust;
1076 		ctx->flags = store->flags;
1077 		ctx->cleanup = store->cleanup;
1078 		}
1079 	else
1080 		{
1081 		ctx->purpose = 0;
1082 		ctx->trust = 0;
1083 		ctx->flags = 0;
1084 		ctx->cleanup = 0;
1085 		}
1086 
1087 	if (store && store->check_issued)
1088 		ctx->check_issued = store->check_issued;
1089 	else
1090 		ctx->check_issued = check_issued;
1091 
1092 	if (store && store->get_issuer)
1093 		ctx->get_issuer = store->get_issuer;
1094 	else
1095 		ctx->get_issuer = X509_STORE_CTX_get1_issuer;
1096 
1097 	if (store && store->verify_cb)
1098 		ctx->verify_cb = store->verify_cb;
1099 	else
1100 		ctx->verify_cb = null_callback;
1101 
1102 	if (store && store->verify)
1103 		ctx->verify = store->verify;
1104 	else
1105 		ctx->verify = internal_verify;
1106 
1107 	if (store && store->check_revocation)
1108 		ctx->check_revocation = store->check_revocation;
1109 	else
1110 		ctx->check_revocation = check_revocation;
1111 
1112 	if (store && store->get_crl)
1113 		ctx->get_crl = store->get_crl;
1114 	else
1115 		ctx->get_crl = get_crl;
1116 
1117 	if (store && store->check_crl)
1118 		ctx->check_crl = store->check_crl;
1119 	else
1120 		ctx->check_crl = check_crl;
1121 
1122 	if (store && store->cert_crl)
1123 		ctx->cert_crl = store->cert_crl;
1124 	else
1125 		ctx->cert_crl = cert_crl;
1126 
1127 
1128 	/* This memset() can't make any sense anyway, so it's removed. As
1129 	 * X509_STORE_CTX_cleanup does a proper "free" on the ex_data, we put a
1130 	 * corresponding "new" here and remove this bogus initialisation. */
1131 	/* memset(&(ctx->ex_data),0,sizeof(CRYPTO_EX_DATA)); */
1132 	if(!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx,
1133 				&(ctx->ex_data)))
1134 		{
1135 		OPENSSL_free(ctx);
1136 		X509err(X509_F_X509_STORE_CTX_INIT,ERR_R_MALLOC_FAILURE);
1137 		return 0;
1138 		}
1139 	return 1;
1140 	}
1141 
1142 /* Set alternative lookup method: just a STACK of trusted certificates.
1143  * This avoids X509_STORE nastiness where it isn't needed.
1144  */
1145 
1146 void X509_STORE_CTX_trusted_stack(X509_STORE_CTX *ctx, STACK_OF(X509) *sk)
1147 {
1148 	ctx->other_ctx = sk;
1149 	ctx->get_issuer = get_issuer_sk;
1150 }
1151 
1152 void X509_STORE_CTX_cleanup(X509_STORE_CTX *ctx)
1153 	{
1154 	if (ctx->cleanup) ctx->cleanup(ctx);
1155 	if (ctx->chain != NULL)
1156 		{
1157 		sk_X509_pop_free(ctx->chain,X509_free);
1158 		ctx->chain=NULL;
1159 		}
1160 	CRYPTO_free_ex_data(CRYPTO_EX_INDEX_X509_STORE_CTX, ctx, &(ctx->ex_data));
1161 	memset(&ctx->ex_data,0,sizeof(CRYPTO_EX_DATA));
1162 	}
1163 
1164 void X509_STORE_CTX_set_flags(X509_STORE_CTX *ctx, long flags)
1165 	{
1166 	ctx->flags |= flags;
1167 	}
1168 
1169 void X509_STORE_CTX_set_time(X509_STORE_CTX *ctx, long flags, time_t t)
1170 	{
1171 	ctx->check_time = t;
1172 	ctx->flags |= X509_V_FLAG_USE_CHECK_TIME;
1173 	}
1174 
1175 void X509_STORE_CTX_set_verify_cb(X509_STORE_CTX *ctx,
1176 				  int (*verify_cb)(int, X509_STORE_CTX *))
1177 	{
1178 	ctx->verify_cb=verify_cb;
1179 	}
1180 
1181 IMPLEMENT_STACK_OF(X509)
1182 IMPLEMENT_ASN1_SET_OF(X509)
1183 
1184 IMPLEMENT_STACK_OF(X509_NAME)
1185 
1186 IMPLEMENT_STACK_OF(X509_ATTRIBUTE)
1187 IMPLEMENT_ASN1_SET_OF(X509_ATTRIBUTE)
1188