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_extensions(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 check_policy(X509_STORE_CTX *ctx);

    81 static int internal_verify(X509_STORE_CTX *ctx);

    82 const char X509_version[]="X.509" OPENSSL_VERSION_PTEXT;

    83 

    84 

    85 static int null_callback(int ok, X509_STORE_CTX *e)

    86 	{

    87 	return ok;

    88 	}

    89 

    90 #if 0

    91 static int x509_subject_cmp(X509 **a, X509 **b)

    92 	{

    93 	return X509_subject_name_cmp(*a,*b);

    94 	}

    95 #endif

    96 

    97 EXPORT_C int X509_verify_cert(X509_STORE_CTX *ctx)

    98 	{

    99 	X509 *x,*xtmp,*chain_ss=NULL;

   100 	X509_NAME *xn;

   101 	int bad_chain = 0;

   102 	X509_VERIFY_PARAM *param = ctx->param;

   103 	int depth,i,ok=0;

   104 	int num;

   105 	int (*cb)(int xok,X509_STORE_CTX *xctx);

   106 	STACK_OF(X509) *sktmp=NULL;

   107 	if (ctx->cert == NULL)

   108 		{

   109 		X509err(X509_F_X509_VERIFY_CERT,X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);

   110 		return -1;

   111 		}

   112 

   113 	cb=ctx->verify_cb;

   114 

   115 	/* first we make sure the chain we are going to build is

   116 	 * present and that the first entry is in place */

   117 	if (ctx->chain == NULL)

   118 		{

   119 		if (	((ctx->chain=sk_X509_new_null()) == NULL) ||

   120 			(!sk_X509_push(ctx->chain,ctx->cert)))

   121 			{

   122 			X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);

   123 			goto end;

   124 			}

   125 		CRYPTO_add(&ctx->cert->references,1,CRYPTO_LOCK_X509);

   126 		ctx->last_untrusted=1;

   127 		}

   128 

   129 	/* We use a temporary STACK so we can chop and hack at it */

   130 	if (ctx->untrusted != NULL

   131 	    && (sktmp=sk_X509_dup(ctx->untrusted)) == NULL)

   132 		{

   133 		X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);

   134 		goto end;

   135 		}

   136 

   137 	num=sk_X509_num(ctx->chain);

   138 	x=sk_X509_value(ctx->chain,num-1);

   139 	depth=param->depth;

   140 

   141 

   142 	for (;;)

   143 		{

   144 		/* If we have enough, we break */

   145 		if (depth < num) break; /* FIXME: If this happens, we should take

   146 		                         * note of it and, if appropriate, use the

   147 		                         * X509_V_ERR_CERT_CHAIN_TOO_LONG error

   148 		                         * code later.

   149 		                         */

   150 

   151 		/* If we are self signed, we break */

   152 		xn=X509_get_issuer_name(x);

   153 		if (ctx->check_issued(ctx, x,x)) break;

   154 

   155 		/* If we were passed a cert chain, use it first */

   156 		if (ctx->untrusted != NULL)

   157 			{

   158 			xtmp=find_issuer(ctx, sktmp,x);

   159 			if (xtmp != NULL)

   160 				{

   161 				if (!sk_X509_push(ctx->chain,xtmp))

   162 					{

   163 					X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);

   164 					goto end;

   165 					}

   166 				CRYPTO_add(&xtmp->references,1,CRYPTO_LOCK_X509);

   167 				(void)sk_X509_delete_ptr(sktmp,xtmp);

   168 				ctx->last_untrusted++;

   169 				x=xtmp;

   170 				num++;

   171 				/* reparse the full chain for

   172 				 * the next one */

   173 				continue;

   174 				}

   175 			}

   176 		break;

   177 		}

   178 

   179 	/* at this point, chain should contain a list of untrusted

   180 	 * certificates.  We now need to add at least one trusted one,

   181 	 * if possible, otherwise we complain. */

   182 

   183 	/* Examine last certificate in chain and see if it

   184  	 * is self signed.

   185  	 */

   186 

   187 	i=sk_X509_num(ctx->chain);

   188 	x=sk_X509_value(ctx->chain,i-1);

   189 	xn = X509_get_subject_name(x);

   190 	if (ctx->check_issued(ctx, x, x))

   191 		{

   192 		/* we have a self signed certificate */

   193 		if (sk_X509_num(ctx->chain) == 1)

   194 			{

   195 			/* We have a single self signed certificate: see if

   196 			 * we can find it in the store. We must have an exact

   197 			 * match to avoid possible impersonation.

   198 			 */

   199 			ok = ctx->get_issuer(&xtmp, ctx, x);

   200 			if ((ok <= 0) || X509_cmp(x, xtmp)) 

   201 				{

   202 				ctx->error=X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT;

   203 				ctx->current_cert=x;

   204 				ctx->error_depth=i-1;

   205 				if (ok == 1) X509_free(xtmp);

   206 				bad_chain = 1;

   207 				ok=cb(0,ctx);

   208 				if (!ok) goto end;

   209 				}

   210 			else 

   211 				{

   212 				/* We have a match: replace certificate with store version

   213 				 * so we get any trust settings.

   214 				 */

   215 				X509_free(x);

   216 				x = xtmp;

   217 				(void)sk_X509_set(ctx->chain, i - 1, x);

   218 				ctx->last_untrusted=0;

   219 				}

   220 			}

   221 		else

   222 			{

   223 			/* extract and save self signed certificate for later use */

   224 			chain_ss=sk_X509_pop(ctx->chain);

   225 			ctx->last_untrusted--;

   226 			num--;

   227 			x=sk_X509_value(ctx->chain,num-1);

   228 			}

   229 		}

   230 

   231 	/* We now lookup certs from the certificate store */

   232 	for (;;)

   233 		{

   234 		/* If we have enough, we break */

   235 		if (depth < num) break;

   236 

   237 		/* If we are self signed, we break */

   238 		xn=X509_get_issuer_name(x);

   239 		if (ctx->check_issued(ctx,x,x)) break;

   240 

   241 		ok = ctx->get_issuer(&xtmp, ctx, x);

   242 

   243 		if (ok < 0) return ok;

   244 		if (ok == 0) break;

   245 

   246 		x = xtmp;

   247 		if (!sk_X509_push(ctx->chain,x))

   248 			{

   249 			X509_free(xtmp);

   250 			X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);

   251 			return 0;

   252 			}

   253 		num++;

   254 		}

   255 

   256 	/* we now have our chain, lets check it... */

   257 	xn=X509_get_issuer_name(x);

   258 

   259 	/* Is last certificate looked up self signed? */

   260 	if (!ctx->check_issued(ctx,x,x))

   261 		{

   262 		if ((chain_ss == NULL) || !ctx->check_issued(ctx, x, chain_ss))

   263 			{

   264 			if (ctx->last_untrusted >= num)

   265 				ctx->error=X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY;

   266 			else

   267 				ctx->error=X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT;

   268 			ctx->current_cert=x;

   269 			}

   270 		else

   271 			{

   272 

   273 			sk_X509_push(ctx->chain,chain_ss);

   274 			num++;

   275 			ctx->last_untrusted=num;

   276 			ctx->current_cert=chain_ss;

   277 			ctx->error=X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN;

   278 			chain_ss=NULL;

   279 			}

   280 

   281 		ctx->error_depth=num-1;

   282 		bad_chain = 1;

   283 		ok=cb(0,ctx);

   284 		if (!ok) goto end;

   285 		}

   286 

   287 	/* We have the chain complete: now we need to check its purpose */

   288 	ok = check_chain_extensions(ctx);

   289 

   290 	if (!ok) goto end;

   291 

   292 	/* The chain extensions are OK: check trust */

   293 

   294 	if (param->trust > 0) ok = check_trust(ctx);

   295 

   296 	if (!ok) goto end;

   297 

   298 	/* We may as well copy down any DSA parameters that are required */

   299 	X509_get_pubkey_parameters(NULL,ctx->chain);

   300 

   301 	/* Check revocation status: we do this after copying parameters

   302 	 * because they may be needed for CRL signature verification.

   303 	 */

   304 

   305 	ok = ctx->check_revocation(ctx);

   306 	if(!ok) goto end;

   307 

   308 	/* At this point, we have a chain and need to verify it */

   309 	if (ctx->verify != NULL)

   310 		ok=ctx->verify(ctx);

   311 	else

   312 		ok=internal_verify(ctx);

   313 	if(!ok) goto end;

   314 

   315 

   316 	/* If we get this far evaluate policies */

   317 	if (!bad_chain && (ctx->param->flags & X509_V_FLAG_POLICY_CHECK))

   318 		ok = ctx->check_policy(ctx);

   319 	if(!ok) goto end;

   320 	if (0)

   321 		{

   322 end:

   323 		X509_get_pubkey_parameters(NULL,ctx->chain);

   324 		}

   325 	if (sktmp != NULL) sk_X509_free(sktmp);

   326 	if (chain_ss != NULL) X509_free(chain_ss);

   327 	return ok;

   328 	}

   329 

   330 

   331 /* Given a STACK_OF(X509) find the issuer of cert (if any)

   332  */

   333 

   334 static X509 *find_issuer(X509_STORE_CTX *ctx, STACK_OF(X509) *sk, X509 *x)

   335 {

   336 	int i;

   337 	X509 *issuer;

   338 	for (i = 0; i < sk_X509_num(sk); i++)

   339 		{

   340 		issuer = sk_X509_value(sk, i);

   341 		if (ctx->check_issued(ctx, x, issuer))

   342 			return issuer;

   343 		}

   344 	return NULL;

   345 }

   346 

   347 /* Given a possible certificate and issuer check them */

   348 

   349 static int check_issued(X509_STORE_CTX *ctx, X509 *x, X509 *issuer)

   350 {

   351 	int ret;

   352 	ret = X509_check_issued(issuer, x);

   353 	if (ret == X509_V_OK)

   354 		return 1;

   355 	/* If we haven't asked for issuer errors don't set ctx */

   356 	if (!(ctx->param->flags & X509_V_FLAG_CB_ISSUER_CHECK))

   357 		return 0;

   358 

   359 	ctx->error = ret;

   360 	ctx->current_cert = x;

   361 	ctx->current_issuer = issuer;

   362 	return ctx->verify_cb(0, ctx);

   363 	return 0;

   364 }

   365 

   366 /* Alternative lookup method: look from a STACK stored in other_ctx */

   367 

   368 static int get_issuer_sk(X509 **issuer, X509_STORE_CTX *ctx, X509 *x)

   369 {

   370 	*issuer = find_issuer(ctx, ctx->other_ctx, x);

   371 	if (*issuer)

   372 		{

   373 		CRYPTO_add(&(*issuer)->references,1,CRYPTO_LOCK_X509);

   374 		return 1;

   375 		}

   376 	else

   377 		return 0;

   378 }

   379 	

   380 

   381 /* Check a certificate chains extensions for consistency

   382  * with the supplied purpose

   383  */

   384 

   385 static int check_chain_extensions(X509_STORE_CTX *ctx)

   386 {

   387 #ifdef OPENSSL_NO_CHAIN_VERIFY

   388 	return 1;

   389 #else

   390 	int i, ok=0, must_be_ca;

   391 	X509 *x;

   392 	int (*cb)(int xok,X509_STORE_CTX *xctx);

   393 	int proxy_path_length = 0;

   394 	int allow_proxy_certs =

   395 		!!(ctx->param->flags & X509_V_FLAG_ALLOW_PROXY_CERTS);

   396 	cb=ctx->verify_cb;

   397 

   398 	/* must_be_ca can have 1 of 3 values:

   399 	   -1: we accept both CA and non-CA certificates, to allow direct

   400 	       use of self-signed certificates (which are marked as CA).

   401 	   0:  we only accept non-CA certificates.  This is currently not

   402 	       used, but the possibility is present for future extensions.

   403 	   1:  we only accept CA certificates.  This is currently used for

   404 	       all certificates in the chain except the leaf certificate.

   405 	*/

   406 	must_be_ca = -1;

   407 

   408 	/* A hack to keep people who don't want to modify their software

   409 	   happy */

   410 	if (getenv("OPENSSL_ALLOW_PROXY_CERTS"))

   411 		allow_proxy_certs = 1;

   412 

   413 	/* Check all untrusted certificates */

   414 	for (i = 0; i < ctx->last_untrusted; i++)

   415 		{

   416 		int ret;

   417 		x = sk_X509_value(ctx->chain, i);

   418 		if (!(ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)

   419 			&& (x->ex_flags & EXFLAG_CRITICAL))

   420 			{

   421 			ctx->error = X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION;

   422 			ctx->error_depth = i;

   423 			ctx->current_cert = x;

   424 			ok=cb(0,ctx);

   425 			if (!ok) goto end;

   426 			}

   427 		if (!allow_proxy_certs && (x->ex_flags & EXFLAG_PROXY))

   428 			{

   429 			ctx->error = X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED;

   430 			ctx->error_depth = i;

   431 			ctx->current_cert = x;

   432 			ok=cb(0,ctx);

   433 			if (!ok) goto end;

   434 			}

   435 		ret = X509_check_ca(x);

   436 		switch(must_be_ca)

   437 			{

   438 		case -1:

   439 			if ((ctx->param->flags & X509_V_FLAG_X509_STRICT)

   440 				&& (ret != 1) && (ret != 0))

   441 				{

   442 				ret = 0;

   443 				ctx->error = X509_V_ERR_INVALID_CA;

   444 				}

   445 			else

   446 				ret = 1;

   447 			break;

   448 		case 0:

   449 			if (ret != 0)

   450 				{

   451 				ret = 0;

   452 				ctx->error = X509_V_ERR_INVALID_NON_CA;

   453 				}

   454 			else

   455 				ret = 1;

   456 			break;

   457 		default:

   458 			if ((ret == 0)

   459 				|| ((ctx->param->flags & X509_V_FLAG_X509_STRICT)

   460 					&& (ret != 1)))

   461 				{

   462 				ret = 0;

   463 				ctx->error = X509_V_ERR_INVALID_CA;

   464 				}

   465 			else

   466 				ret = 1;

   467 			break;

   468 			}

   469 		if (ret == 0)

   470 			{

   471 			ctx->error_depth = i;

   472 			ctx->current_cert = x;

   473 			ok=cb(0,ctx);

   474 			if (!ok) goto end;

   475 			}

   476 		if (ctx->param->purpose > 0)

   477 			{

   478 			ret = X509_check_purpose(x, ctx->param->purpose,

   479 				must_be_ca > 0);

   480 			if ((ret == 0)

   481 				|| ((ctx->param->flags & X509_V_FLAG_X509_STRICT)

   482 					&& (ret != 1)))

   483 				{

   484 				ctx->error = X509_V_ERR_INVALID_PURPOSE;

   485 				ctx->error_depth = i;

   486 				ctx->current_cert = x;

   487 				ok=cb(0,ctx);

   488 				if (!ok) goto end;

   489 				}

   490 			}

   491 		/* Check pathlen */

   492 		if ((i > 1) && (x->ex_pathlen != -1)

   493 			   && (i > (x->ex_pathlen + proxy_path_length + 1)))

   494 			{

   495 			ctx->error = X509_V_ERR_PATH_LENGTH_EXCEEDED;

   496 			ctx->error_depth = i;

   497 			ctx->current_cert = x;

   498 			ok=cb(0,ctx);

   499 			if (!ok) goto end;

   500 			}

   501 		/* If this certificate is a proxy certificate, the next

   502 		   certificate must be another proxy certificate or a EE

   503 		   certificate.  If not, the next certificate must be a

   504 		   CA certificate.  */

   505 		if (x->ex_flags & EXFLAG_PROXY)

   506 			{

   507 			if (x->ex_pcpathlen != -1 && i > x->ex_pcpathlen)

   508 				{

   509 				ctx->error =

   510 					X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED;

   511 				ctx->error_depth = i;

   512 				ctx->current_cert = x;

   513 				ok=cb(0,ctx);

   514 				if (!ok) goto end;

   515 				}

   516 			proxy_path_length++;

   517 			must_be_ca = 0;

   518 			}

   519 		else

   520 			must_be_ca = 1;

   521 		}

   522 	ok = 1;

   523  end:

   524 	return ok;

   525 #endif

   526 }

   527 

   528 static int check_trust(X509_STORE_CTX *ctx)

   529 {

   530 #ifdef OPENSSL_NO_CHAIN_VERIFY

   531 	return 1;

   532 #else

   533 	int i, ok;

   534 	X509 *x;

   535 	int (*cb)(int xok,X509_STORE_CTX *xctx);

   536 	cb=ctx->verify_cb;

   537 /* For now just check the last certificate in the chain */

   538 	i = sk_X509_num(ctx->chain) - 1;

   539 	x = sk_X509_value(ctx->chain, i);

   540 	ok = X509_check_trust(x, ctx->param->trust, 0);

   541 	if (ok == X509_TRUST_TRUSTED)

   542 		return 1;

   543 	ctx->error_depth = i;

   544 	ctx->current_cert = x;

   545 	if (ok == X509_TRUST_REJECTED)

   546 		ctx->error = X509_V_ERR_CERT_REJECTED;

   547 	else

   548 		ctx->error = X509_V_ERR_CERT_UNTRUSTED;

   549 	ok = cb(0, ctx);

   550 	return ok;

   551 #endif

   552 }

   553 

   554 static int check_revocation(X509_STORE_CTX *ctx)

   555 	{

   556 	int i, last, ok;

   557 	if (!(ctx->param->flags & X509_V_FLAG_CRL_CHECK))

   558 		return 1;

   559 	if (ctx->param->flags & X509_V_FLAG_CRL_CHECK_ALL)

   560 		last = sk_X509_num(ctx->chain) - 1;

   561 	else

   562 		last = 0;

   563 	for(i = 0; i <= last; i++)

   564 		{

   565 		ctx->error_depth = i;

   566 		ok = check_cert(ctx);

   567 		if (!ok) return ok;

   568 		}

   569 	return 1;

   570 	}

   571 

   572 static int check_cert(X509_STORE_CTX *ctx)

   573 	{

   574 	X509_CRL *crl = NULL;

   575 	X509 *x;

   576 	int ok, cnum;

   577 	cnum = ctx->error_depth;

   578 	x = sk_X509_value(ctx->chain, cnum);

   579 	ctx->current_cert = x;

   580 	/* Try to retrieve relevant CRL */

   581 	ok = ctx->get_crl(ctx, &crl, x);

   582 	/* If error looking up CRL, nothing we can do except

   583 	 * notify callback

   584 	 */

   585 	if(!ok)

   586 		{

   587 		ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL;

   588 		ok = ctx->verify_cb(0, ctx);

   589 		goto err;

   590 		}

   591 	ctx->current_crl = crl;

   592 	ok = ctx->check_crl(ctx, crl);

   593 	if (!ok) goto err;

   594 	ok = ctx->cert_crl(ctx, crl, x);

   595 	err:

   596 	ctx->current_crl = NULL;

   597 	X509_CRL_free(crl);

   598 	return ok;

   599 

   600 	}

   601 

   602 /* Check CRL times against values in X509_STORE_CTX */

   603 

   604 static int check_crl_time(X509_STORE_CTX *ctx, X509_CRL *crl, int notify)

   605 	{

   606 	time_t *ptime;

   607 	int i;

   608 	ctx->current_crl = crl;

   609 	if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)

   610 		ptime = &ctx->param->check_time;

   611 	else

   612 		ptime = NULL;

   613 

   614 	i=X509_cmp_time(X509_CRL_get_lastUpdate(crl), ptime);

   615 	if (i == 0)

   616 		{

   617 		ctx->error=X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD;

   618 		if (!notify || !ctx->verify_cb(0, ctx))

   619 			return 0;

   620 		}

   621 

   622 	if (i > 0)

   623 		{

   624 		ctx->error=X509_V_ERR_CRL_NOT_YET_VALID;

   625 		if (!notify || !ctx->verify_cb(0, ctx))

   626 			return 0;

   627 		}

   628 

   629 	if(X509_CRL_get_nextUpdate(crl))

   630 		{

   631 		i=X509_cmp_time(X509_CRL_get_nextUpdate(crl), ptime);

   632 

   633 		if (i == 0)

   634 			{

   635 			ctx->error=X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD;

   636 			if (!notify || !ctx->verify_cb(0, ctx))

   637 				return 0;

   638 			}

   639 

   640 		if (i < 0)

   641 			{

   642 			ctx->error=X509_V_ERR_CRL_HAS_EXPIRED;

   643 			if (!notify || !ctx->verify_cb(0, ctx))

   644 				return 0;

   645 			}

   646 		}

   647 

   648 	ctx->current_crl = NULL;

   649 

   650 	return 1;

   651 	}

   652 

   653 /* Lookup CRLs from the supplied list. Look for matching isser name

   654  * and validity. If we can't find a valid CRL return the last one

   655  * with matching name. This gives more meaningful error codes. Otherwise

   656  * we'd get a CRL not found error if a CRL existed with matching name but

   657  * was invalid.

   658  */

   659 

   660 static int get_crl_sk(X509_STORE_CTX *ctx, X509_CRL **pcrl,

   661 			X509_NAME *nm, STACK_OF(X509_CRL) *crls)

   662 	{

   663 	int i;

   664 	X509_CRL *crl, *best_crl = NULL;

   665 	for (i = 0; i < sk_X509_CRL_num(crls); i++)

   666 		{

   667 		crl = sk_X509_CRL_value(crls, i);

   668 		if (X509_NAME_cmp(nm, X509_CRL_get_issuer(crl)))

   669 			continue;

   670 		if (check_crl_time(ctx, crl, 0))

   671 			{

   672 			*pcrl = crl;

   673 			CRYPTO_add(&crl->references, 1, CRYPTO_LOCK_X509);

   674 			return 1;

   675 			}

   676 		best_crl = crl;

   677 		}

   678 	if (best_crl)

   679 		{

   680 		*pcrl = best_crl;

   681 		CRYPTO_add(&best_crl->references, 1, CRYPTO_LOCK_X509);

   682 		}

   683 		

   684 	return 0;

   685 	}

   686 

   687 /* Retrieve CRL corresponding to certificate: currently just a

   688  * subject lookup: maybe use AKID later...

   689  */

   690 static int get_crl(X509_STORE_CTX *ctx, X509_CRL **pcrl, X509 *x)

   691 	{

   692 	int ok;

   693 	X509_CRL *crl = NULL;

   694 	X509_OBJECT xobj;

   695 	X509_NAME *nm;

   696 	nm = X509_get_issuer_name(x);

   697 	ok = get_crl_sk(ctx, &crl, nm, ctx->crls);

   698 	if (ok)

   699 		{

   700 		*pcrl = crl;

   701 		return 1;

   702 		}

   703 

   704 	ok = X509_STORE_get_by_subject(ctx, X509_LU_CRL, nm, &xobj);

   705 

   706 	if (!ok)

   707 		{

   708 		/* If we got a near match from get_crl_sk use that */

   709 		if (crl)

   710 			{

   711 			*pcrl = crl;

   712 			return 1;

   713 			}

   714 		return 0;

   715 		}

   716 

   717 	*pcrl = xobj.data.crl;

   718 	if (crl)

   719 		X509_CRL_free(crl);

   720 	return 1;

   721 	}

   722 

   723 /* Check CRL validity */

   724 static int check_crl(X509_STORE_CTX *ctx, X509_CRL *crl)

   725 	{

   726 	X509 *issuer = NULL;

   727 	EVP_PKEY *ikey = NULL;

   728 	int ok = 0, chnum, cnum;

   729 	cnum = ctx->error_depth;

   730 	chnum = sk_X509_num(ctx->chain) - 1;

   731 	/* Find CRL issuer: if not last certificate then issuer

   732 	 * is next certificate in chain.

   733 	 */

   734 	if(cnum < chnum)

   735 		issuer = sk_X509_value(ctx->chain, cnum + 1);

   736 	else

   737 		{

   738 		issuer = sk_X509_value(ctx->chain, chnum);

   739 		/* If not self signed, can't check signature */

   740 		if(!ctx->check_issued(ctx, issuer, issuer))

   741 			{

   742 			ctx->error = X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER;

   743 			ok = ctx->verify_cb(0, ctx);

   744 			if(!ok) goto err;

   745 			}

   746 		}

   747 

   748 	if(issuer)

   749 		{

   750 		/* Check for cRLSign bit if keyUsage present */

   751 		if ((issuer->ex_flags & EXFLAG_KUSAGE) &&

   752 			!(issuer->ex_kusage & KU_CRL_SIGN))

   753 			{

   754 			ctx->error = X509_V_ERR_KEYUSAGE_NO_CRL_SIGN;

   755 			ok = ctx->verify_cb(0, ctx);

   756 			if(!ok) goto err;

   757 			}

   758 

   759 		/* Attempt to get issuer certificate public key */

   760 		ikey = X509_get_pubkey(issuer);

   761 

   762 		if(!ikey)

   763 			{

   764 			ctx->error=X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;

   765 			ok = ctx->verify_cb(0, ctx);

   766 			if (!ok) goto err;

   767 			}

   768 		else

   769 			{

   770 			/* Verify CRL signature */

   771 			if(X509_CRL_verify(crl, ikey) <= 0)

   772 				{

   773 				ctx->error=X509_V_ERR_CRL_SIGNATURE_FAILURE;

   774 				ok = ctx->verify_cb(0, ctx);

   775 				if (!ok) goto err;

   776 				}

   777 			}

   778 		}

   779 

   780 	ok = check_crl_time(ctx, crl, 1);

   781 	if (!ok)

   782 		goto err;

   783 

   784 	ok = 1;

   785 

   786 	err:

   787 	EVP_PKEY_free(ikey);

   788 	return ok;

   789 	}

   790 

   791 /* Check certificate against CRL */

   792 static int cert_crl(X509_STORE_CTX *ctx, X509_CRL *crl, X509 *x)

   793 	{

   794 	int idx, ok;

   795 	X509_REVOKED rtmp;

   796 	STACK_OF(X509_EXTENSION) *exts;

   797 	X509_EXTENSION *ext;

   798 	/* Look for serial number of certificate in CRL */

   799 	rtmp.serialNumber = X509_get_serialNumber(x);

   800 	/* Sort revoked into serial number order if not already sorted.

   801 	 * Do this under a lock to avoid race condition.

   802  	 */

   803 	if (!sk_X509_REVOKED_is_sorted(crl->crl->revoked))

   804 		{

   805 		CRYPTO_w_lock(CRYPTO_LOCK_X509_CRL);

   806 		sk_X509_REVOKED_sort(crl->crl->revoked);

   807 		CRYPTO_w_unlock(CRYPTO_LOCK_X509_CRL);

   808 		}

   809 	idx = sk_X509_REVOKED_find(crl->crl->revoked, &rtmp);

   810 	/* If found assume revoked: want something cleverer than

   811 	 * this to handle entry extensions in V2 CRLs.

   812 	 */

   813 	if(idx >= 0)

   814 		{

   815 		ctx->error = X509_V_ERR_CERT_REVOKED;

   816 		ok = ctx->verify_cb(0, ctx);

   817 		if (!ok) return 0;

   818 		}

   819 

   820 	if (ctx->param->flags & X509_V_FLAG_IGNORE_CRITICAL)

   821 		return 1;

   822 

   823 	/* See if we have any critical CRL extensions: since we

   824 	 * currently don't handle any CRL extensions the CRL must be

   825 	 * rejected. 

   826 	 * This code accesses the X509_CRL structure directly: applications

   827 	 * shouldn't do this.

   828 	 */

   829 

   830 	exts = crl->crl->extensions;

   831 

   832 	for (idx = 0; idx < sk_X509_EXTENSION_num(exts); idx++)

   833 		{

   834 		ext = sk_X509_EXTENSION_value(exts, idx);

   835 		if (ext->critical > 0)

   836 			{

   837 			ctx->error =

   838 				X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION;

   839 			ok = ctx->verify_cb(0, ctx);

   840 			if(!ok) return 0;

   841 			break;

   842 			}

   843 		}

   844 	return 1;

   845 	}

   846 

   847 static int check_policy(X509_STORE_CTX *ctx)

   848 	{

   849 	int ret;

   850 	ret = X509_policy_check(&ctx->tree, &ctx->explicit_policy, ctx->chain,

   851 				ctx->param->policies, ctx->param->flags);

   852 	if (ret == 0)

   853 		{

   854 		X509err(X509_F_CHECK_POLICY,ERR_R_MALLOC_FAILURE);

   855 		return 0;

   856 		}

   857 	/* Invalid or inconsistent extensions */

   858 	if (ret == -1)

   859 		{

   860 		/* Locate certificates with bad extensions and notify

   861 		 * callback.

   862 		 */

   863 		X509 *x;

   864 		int i;

   865 		for (i = 1; i < sk_X509_num(ctx->chain); i++)

   866 			{

   867 			x = sk_X509_value(ctx->chain, i);

   868 			if (!(x->ex_flags & EXFLAG_INVALID_POLICY))

   869 				continue;

   870 			ctx->current_cert = x;

   871 			ctx->error = X509_V_ERR_INVALID_POLICY_EXTENSION;

   872 			ret = ctx->verify_cb(0, ctx);

   873 			}

   874 		return 1;

   875 		}

   876 	if (ret == -2)

   877 		{

   878 		ctx->current_cert = NULL;

   879 		ctx->error = X509_V_ERR_NO_EXPLICIT_POLICY;

   880 		return ctx->verify_cb(0, ctx);

   881 		}

   882 

   883 	if (ctx->param->flags & X509_V_FLAG_NOTIFY_POLICY)

   884 		{

   885 		ctx->current_cert = NULL;

   886 		ctx->error = X509_V_OK;

   887 		if (!ctx->verify_cb(2, ctx))

   888 			return 0;

   889 		}

   890 

   891 	return 1;

   892 	}

   893 

   894 static int check_cert_time(X509_STORE_CTX *ctx, X509 *x)

   895 	{

   896 	time_t *ptime;

   897 	int i;

   898 

   899 	if (ctx->param->flags & X509_V_FLAG_USE_CHECK_TIME)

   900 		ptime = &ctx->param->check_time;

   901 	else

   902 		ptime = NULL;

   903 

   904 	i=X509_cmp_time(X509_get_notBefore(x), ptime);

   905 	if (i == 0)

   906 		{

   907 		ctx->error=X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD;

   908 		ctx->current_cert=x;

   909 		if (!ctx->verify_cb(0, ctx))

   910 			return 0;

   911 		}

   912 

   913 	if (i > 0)

   914 		{

   915 		ctx->error=X509_V_ERR_CERT_NOT_YET_VALID;

   916 		ctx->current_cert=x;

   917 		if (!ctx->verify_cb(0, ctx))

   918 			return 0;

   919 		}

   920 

   921 	i=X509_cmp_time(X509_get_notAfter(x), ptime);

   922 	if (i == 0)

   923 		{

   924 		ctx->error=X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD;

   925 		ctx->current_cert=x;

   926 		if (!ctx->verify_cb(0, ctx))

   927 			return 0;

   928 		}

   929 

   930 	if (i < 0)

   931 		{

   932 		ctx->error=X509_V_ERR_CERT_HAS_EXPIRED;

   933 		ctx->current_cert=x;

   934 		if (!ctx->verify_cb(0, ctx))

   935 			return 0;

   936 		}

   937 

   938 	return 1;

   939 	}

   940 

   941 static int internal_verify(X509_STORE_CTX *ctx)

   942 	{

   943 	int ok=0,n;

   944 	X509 *xs,*xi;

   945 	EVP_PKEY *pkey=NULL;

   946 	int (*cb)(int xok,X509_STORE_CTX *xctx);

   947 

   948 	cb=ctx->verify_cb;

   949 

   950 	n=sk_X509_num(ctx->chain);

   951 	ctx->error_depth=n-1;

   952 	n--;

   953 	xi=sk_X509_value(ctx->chain,n);

   954 

   955 	if (ctx->check_issued(ctx, xi, xi))

   956 		xs=xi;

   957 	else

   958 		{

   959 		if (n <= 0)

   960 			{

   961 			ctx->error=X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE;

   962 			ctx->current_cert=xi;

   963 			ok=cb(0,ctx);

   964 			goto end;

   965 			}

   966 		else

   967 			{

   968 			n--;

   969 			ctx->error_depth=n;

   970 			xs=sk_X509_value(ctx->chain,n);

   971 			}

   972 		}

   973 

   974 /*	ctx->error=0;  not needed */

   975 	while (n >= 0)

   976 		{

   977 		ctx->error_depth=n;

   978 		if (!xs->valid)

   979 			{

   980 			if ((pkey=X509_get_pubkey(xi)) == NULL)

   981 				{

   982 				ctx->error=X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;

   983 				ctx->current_cert=xi;

   984 				ok=(*cb)(0,ctx);

   985 				if (!ok) goto end;

   986 				}

   987 			else if (X509_verify(xs,pkey) <= 0)

   988 				/* XXX  For the final trusted self-signed cert,

   989 				 * this is a waste of time.  That check should

   990 				 * optional so that e.g. 'openssl x509' can be

   991 				 * used to detect invalid self-signatures, but

   992 				 * we don't verify again and again in SSL

   993 				 * handshakes and the like once the cert has

   994 				 * been declared trusted. */

   995 				{

   996 				ctx->error=X509_V_ERR_CERT_SIGNATURE_FAILURE;

   997 				ctx->current_cert=xs;

   998 				ok=(*cb)(0,ctx);

   999 				if (!ok)

  1000 					{

  1001 					EVP_PKEY_free(pkey);

  1002 					goto end;

  1003 					}

  1004 				}

  1005 			EVP_PKEY_free(pkey);

  1006 			pkey=NULL;

  1007 			}

  1008 

  1009 		xs->valid = 1;

  1010 

  1011 		ok = check_cert_time(ctx, xs);

  1012 		if (!ok)

  1013 			goto end;

  1014 

  1015 		/* The last error (if any) is still in the error value */

  1016 		ctx->current_issuer=xi;

  1017 		ctx->current_cert=xs;

  1018 		ok=(*cb)(1,ctx);

  1019 		if (!ok) goto end;

  1020 

  1021 		n--;

  1022 		if (n >= 0)

  1023 			{

  1024 			xi=xs;

  1025 			xs=sk_X509_value(ctx->chain,n);

  1026 			}

  1027 		}

  1028 	ok=1;

  1029 end:

  1030 	return ok;

  1031 	}

  1032 

  1033 EXPORT_C int X509_cmp_current_time(ASN1_TIME *ctm)

  1034 {

  1035 	return X509_cmp_time(ctm, NULL);

  1036 }

  1037 

  1038 EXPORT_C int X509_cmp_time(ASN1_TIME *ctm, time_t *cmp_time)

  1039 	{

  1040 	char *str;

  1041 	ASN1_TIME atm;

  1042 	long offset;

  1043 	char buff1[24],buff2[24],*p;

  1044 	int i,j;

  1045 

  1046 	p=buff1;

  1047 	i=ctm->length;

  1048 	str=(char *)ctm->data;

  1049 	if (ctm->type == V_ASN1_UTCTIME)

  1050 		{

  1051 		if ((i < 11) || (i > 17)) return 0;

  1052 		memcpy(p,str,10);

  1053 		p+=10;

  1054 		str+=10;

  1055 		}

  1056 	else

  1057 		{

  1058 		if (i < 13) return 0;

  1059 		memcpy(p,str,12);

  1060 		p+=12;

  1061 		str+=12;

  1062 		}

  1063 

  1064 	if ((*str == 'Z') || (*str == '-') || (*str == '+'))

  1065 		{ *(p++)='0'; *(p++)='0'; }

  1066 	else

  1067 		{ 

  1068 		*(p++)= *(str++);

  1069 		*(p++)= *(str++);

  1070 		/* Skip any fractional seconds... */

  1071 		if (*str == '.')

  1072 			{

  1073 			str++;

  1074 			while ((*str >= '0') && (*str <= '9')) str++;

  1075 			}

  1076 		

  1077 		}

  1078 	*(p++)='Z';

  1079 	*(p++)='\0';

  1080 

  1081 	if (*str == 'Z')

  1082 		offset=0;

  1083 	else

  1084 		{

  1085 		if ((*str != '+') && (*str != '-'))

  1086 			return 0;

  1087 		offset=((str[1]-'0')*10+(str[2]-'0'))*60;

  1088 		offset+=(str[3]-'0')*10+(str[4]-'0');

  1089 		if (*str == '-')

  1090 			offset= -offset;

  1091 		}

  1092 	atm.type=ctm->type;

  1093 	atm.length=sizeof(buff2);

  1094 	atm.data=(unsigned char *)buff2;

  1095 

  1096 	if (X509_time_adj(&atm,-offset*60, cmp_time) == NULL)

  1097 		return 0;

  1098 

  1099 	if (ctm->type == V_ASN1_UTCTIME)

  1100 		{

  1101 		i=(buff1[0]-'0')*10+(buff1[1]-'0');

  1102 		if (i < 50) i+=100; /* cf. RFC 2459 */

  1103 		j=(buff2[0]-'0')*10+(buff2[1]-'0');

  1104 		if (j < 50) j+=100;

  1105 

  1106 		if (i < j) return -1;

  1107 		if (i > j) return 1;

  1108 		}

  1109 	i=strcmp(buff1,buff2);

  1110 	if (i == 0) /* wait a second then return younger :-) */

  1111 		return -1;

  1112 	else

  1113 		return i;

  1114 	}

  1115 

  1116 EXPORT_C ASN1_TIME *X509_gmtime_adj(ASN1_TIME *s, long adj)

  1117 {

  1118 	return X509_time_adj(s, adj, NULL);

  1119 }

  1120 

  1121 EXPORT_C ASN1_TIME *X509_time_adj(ASN1_TIME *s, long adj, time_t *in_tm)

  1122 	{

  1123 	time_t t;

  1124 	int type = -1;

  1125 

  1126 	if (in_tm) t = *in_tm;

  1127 	else time(&t);

  1128 

  1129 	t+=adj;

  1130 	if (s) type = s->type;

  1131 	if (type == V_ASN1_UTCTIME) return ASN1_UTCTIME_set(s,t);

  1132 	if (type == V_ASN1_GENERALIZEDTIME) return ASN1_GENERALIZEDTIME_set(s, t);

  1133 	return ASN1_TIME_set(s, t);

  1134 	}

  1135