crypto/x509/x509_vfy.c

   1 /* crypto/x509/x509_vfy.c */
   2 /* Copyright (C) 1995-1997 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 #include <sys/types.h>
  63 #include <sys/stat.h>
  64
  65 #include "cryptlib.h"
  66 #include "lhash.h"
  67 #include "buffer.h"
  68 #include "evp.h"
  69 #include "asn1.h"
  70 #include "x509.h"
  71 #include "objects.h"
  72 #include "pem.h"
  73
  74 #ifndef NOPROTO
  75 static int null_callback(int ok,X509_STORE_CTX *e);
  76 static int internal_verify(X509_STORE_CTX *ctx);
  77 #else
  78 static int null_callback();
  79 static int internal_verify();
  80 #endif
  81
  82 char *X509_version="X509 part of SSLeay 0.8.1b 29-Jun-1998";
  83
  84 static int null_callback(ok,e)
  85 int ok;
  86 X509_STORE_CTX *e;
  87         {
  88         return(ok);
  89         }
  90
  91 #if 0
  92 static int x509_subject_cmp(a,b)
  93 X509 **a,**b;
  94         {
  95         return(X509_subject_name_cmp(*a,*b));
  96         }
  97 #endif
  98
  99 int X509_verify_cert(ctx)
 100 X509_STORE_CTX *ctx;
 101         {
 102         X509 *x,*xtmp,*chain_ss=NULL;
 103         X509_NAME *xn;
 104         X509_OBJECT obj;
 105         int depth,i,ok=0;
 106         int num;
 107         int (*cb)();
 108         STACK *sktmp=NULL;
 109
 110         if (ctx->cert == NULL)
 111                 {
 112                 X509err(X509_F_X509_VERIFY_CERT,X509_R_NO_CERT_SET_FOR_US_TO_VERIFY);
 113                 return(-1);
 114                 }
 115
 116         cb=ctx->ctx->verify_cb;
 117         if (cb == NULL) cb=null_callback;
 118
 119         /* first we make sure the chain we are going to build is
 120          * present and that the first entry is in place */
 121         if (ctx->chain == NULL)
 122                 {
 123                 if (    ((ctx->chain=sk_new_null()) == NULL) ||
 124                         (!sk_push(ctx->chain,(char *)ctx->cert)))
 125                         {
 126                         X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
 127                         goto end;
 128                         }
 129                 CRYPTO_add(&ctx->cert->references,1,CRYPTO_LOCK_X509);
 130                 ctx->last_untrusted=1;
 131                 }
 132
 133         /* We use a temporary so we can chop and hack at it */
 134         if ((ctx->untrusted != NULL) && (sktmp=sk_dup(ctx->untrusted)) == NULL)
 135                 {
 136                 X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
 137                 goto end;
 138                 }
 139
 140         num=sk_num(ctx->chain);
 141         x=(X509 *)sk_value(ctx->chain,num-1);
 142         depth=ctx->depth;
 143
 144
 145         for (;;)
 146                 {
 147                 /* If we have enough, we break */
 148                 if (depth <= num) break;
 149
 150                 /* If we are self signed, we break */
 151                 xn=X509_get_issuer_name(x);
 152                 if (X509_NAME_cmp(X509_get_subject_name(x),xn) == 0)
 153                         break;
 154
 155                 /* If we were passed a cert chain, use it first */
 156                 if (ctx->untrusted != NULL)
 157                         {
 158                         xtmp=X509_find_by_subject(sktmp,xn);
 159                         if (xtmp != NULL)
 160                                 {
 161                                 if (!sk_push(ctx->chain,(char *)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                                 sk_delete_ptr(sktmp,(char *)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         i=sk_num(ctx->chain);
 184         x=(X509 *)sk_value(ctx->chain,i-1);
 185         if (X509_NAME_cmp(X509_get_subject_name(x),X509_get_issuer_name(x))
 186                 == 0)
 187                 {
 188                 /* we have a self signed certificate */
 189                 if (sk_num(ctx->chain) == 1)
 190                         {
 191                         ctx->error=X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT;
 192                         ctx->current_cert=x;
 193                         ctx->error_depth=i-1;
 194                         ok=cb(0,ctx);
 195                         if (!ok) goto end;
 196                         }
 197                 else
 198                         {
 199                         /* worry more about this one elsewhere */
 200                         chain_ss=(X509 *)sk_pop(ctx->chain);
 201                         ctx->last_untrusted--;
 202                         num--;
 203                         x=(X509 *)sk_value(ctx->chain,num-1);
 204                         }
 205                 }
 206
 207         /* We now lookup certs from the certificate store */
 208         for (;;)
 209                 {
 210                 /* If we have enough, we break */
 211                 if (depth <= num) break;
 212
 213                 /* If we are self signed, we break */
 214                 xn=X509_get_issuer_name(x);
 215                 if (X509_NAME_cmp(X509_get_subject_name(x),xn) == 0)
 216                         break;
 217
 218                 ok=X509_STORE_get_by_subject(ctx,X509_LU_X509,xn,&obj);
 219                 if (ok != X509_LU_X509)
 220                         {
 221                         if (ok == X509_LU_RETRY)
 222                                 {
 223                                 X509_OBJECT_free_contents(&obj);
 224                                 X509err(X509_F_X509_VERIFY_CERT,X509_R_SHOULD_RETRY);
 225                                 return(ok);
 226                                 }
 227                         else if (ok != X509_LU_FAIL)
 228                                 {
 229                                 X509_OBJECT_free_contents(&obj);
 230                                 /* not good :-(, break anyway */
 231                                 return(ok);
 232                                 }
 233                         break;
 234                         }
 235                 x=obj.data.x509;
 236                 if (!sk_push(ctx->chain,(char *)obj.data.x509))
 237                         {
 238                         X509_OBJECT_free_contents(&obj);
 239                         X509err(X509_F_X509_VERIFY_CERT,ERR_R_MALLOC_FAILURE);
 240                         return(0);
 241                         }
 242                 num++;
 243                 }
 244
 245         /* we now have our chain, lets check it... */
 246         xn=X509_get_issuer_name(x);
 247         if (X509_NAME_cmp(X509_get_subject_name(x),xn) != 0)
 248                 {
 249                 if ((chain_ss == NULL) || (X509_NAME_cmp(X509_get_subject_name(chain_ss),xn) != 0))
 250                         {
 251                         if (ctx->last_untrusted >= num)
 252                                 ctx->error=X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY;
 253                         else
 254                                 ctx->error=X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT;
 255                         ctx->current_cert=x;
 256                         }
 257                 else
 258                         {
 259
 260                         sk_push(ctx->chain,(char *)chain_ss);
 261                         num++;
 262                         ctx->last_untrusted=num;
 263                         ctx->current_cert=chain_ss;
 264                         ctx->error=X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN;
 265                         chain_ss=NULL;
 266                         }
 267
 268                 ctx->error_depth=num-1;
 269                 ok=cb(0,ctx);
 270                 if (!ok) goto end;
 271                 }
 272
 273         /* We may as well copy down any DSA parameters that are required */
 274         X509_get_pubkey_parameters(NULL,ctx->chain);
 275
 276         /* At this point, we have a chain and just need to verify it */
 277         if (ctx->ctx->verify != NULL)
 278                 ok=ctx->ctx->verify(ctx);
 279         else
 280                 ok=internal_verify(ctx);
 281 end:
 282         if (sktmp != NULL) sk_free(sktmp);
 283         if (chain_ss != NULL) X509_free(chain_ss);
 284         return(ok);
 285         }
 286
 287 static int internal_verify(ctx)
 288 X509_STORE_CTX *ctx;
 289         {
 290         int i,ok=0,n;
 291         X509 *xs,*xi;
 292         EVP_PKEY *pkey=NULL;
 293         int (*cb)();
 294
 295         cb=ctx->ctx->verify_cb;
 296         if (cb == NULL) cb=null_callback;
 297
 298         n=sk_num(ctx->chain);
 299         ctx->error_depth=n-1;
 300         n--;
 301         xi=(X509 *)sk_value(ctx->chain,n);
 302         if (X509_NAME_cmp(X509_get_subject_name(xi),
 303                 X509_get_issuer_name(xi)) == 0)
 304                 xs=xi;
 305         else
 306                 {
 307                 if (n <= 0)
 308                         {
 309                         ctx->error=X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE;
 310                         ctx->current_cert=xi;
 311                         ok=cb(0,ctx);
 312                         goto end;
 313                         }
 314                 else
 315                         {
 316                         n--;
 317                         ctx->error_depth=n;
 318                         xs=(X509 *)sk_value(ctx->chain,n);
 319                         }
 320                 }
 321
 322 /*      ctx->error=0;  not needed */
 323         while (n >= 0)
 324                 {
 325                 ctx->error_depth=n;
 326                 if (!xs->valid)
 327                         {
 328                         if ((pkey=X509_get_pubkey(xi)) == NULL)
 329                                 {
 330                                 ctx->error=X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY;
 331                                 ctx->current_cert=xi;
 332                                 ok=(*cb)(0,ctx);
 333                                 if (!ok) goto end;
 334                                 }
 335                         if (X509_verify(xs,pkey) <= 0)
 336                                 {
 337                                 ctx->error=X509_V_ERR_CERT_SIGNATURE_FAILURE;
 338                                 ctx->current_cert=xs;
 339                                 ok=(*cb)(0,ctx);
 340                                 if (!ok) goto end;
 341                                 }
 342                         pkey=NULL;
 343
 344                         i=X509_cmp_current_time(X509_get_notBefore(xs));
 345                         if (i == 0)
 346                                 {
 347                                 ctx->error=X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD;
 348                                 ctx->current_cert=xs;
 349                                 ok=(*cb)(0,ctx);
 350                                 if (!ok) goto end;
 351                                 }
 352                         if (i > 0)
 353                                 {
 354                                 ctx->error=X509_V_ERR_CERT_NOT_YET_VALID;
 355                                 ctx->current_cert=xs;
 356                                 ok=(*cb)(0,ctx);
 357                                 if (!ok) goto end;
 358                                 }
 359                         xs->valid=1;
 360                         }
 361
 362                 i=X509_cmp_current_time(X509_get_notAfter(xs));
 363                 if (i == 0)
 364                         {
 365                         ctx->error=X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD;
 366                         ctx->current_cert=xs;
 367                         ok=(*cb)(0,ctx);
 368                         if (!ok) goto end;
 369                         }
 370
 371                 if (i < 0)
 372                         {
 373                         ctx->error=X509_V_ERR_CERT_HAS_EXPIRED;
 374                         ctx->current_cert=xs;
 375                         ok=(*cb)(0,ctx);
 376                         if (!ok) goto end;
 377                         }
 378
 379                 /* CRL CHECK */
 380
 381                 /* The last error (if any) is still in the error value */
 382                 ctx->current_cert=xs;
 383                 ok=(*cb)(1,ctx);
 384                 if (!ok) goto end;
 385
 386                 n--;
 387                 if (n >= 0)
 388                         {
 389                         xi=xs;
 390                         xs=(X509 *)sk_value(ctx->chain,n);
 391                         }
 392                 }
 393         ok=1;
 394 end:
 395         return(ok);
 396         }
 397
 398 int X509_cmp_current_time(ctm)
 399 ASN1_UTCTIME *ctm;
 400         {
 401         char *str;
 402         ASN1_UTCTIME atm;
 403         time_t offset;
 404         char buff1[24],buff2[24],*p;
 405         int i,j;
 406
 407         p=buff1;
 408         i=ctm->length;
 409         str=(char *)ctm->data;
 410         if ((i < 11) || (i > 17)) return(0);
 411         memcpy(p,str,10);
 412         p+=10;
 413         str+=10;
 414
 415         if ((*str == 'Z') || (*str == '-') || (*str == '+'))
 416                 { *(p++)='0'; *(p++)='0'; }
 417         else    { *(p++)= *(str++); *(p++)= *(str++); }
 418         *(p++)='Z';
 419         *(p++)='\0';
 420
 421         if (*str == 'Z')
 422                 offset=0;
 423         else
 424                 {
 425                 if ((*str != '+') && (str[5] != '-'))
 426                         return(0);
 427                 offset=((str[1]-'0')*10+(str[2]-'0'))*60;
 428                 offset+=(str[3]-'0')*10+(str[4]-'0');
 429                 if (*str == '-')
 430                         offset-=offset;
 431                 }
 432         atm.type=V_ASN1_UTCTIME;
 433         atm.length=sizeof(buff2);
 434         atm.data=(unsigned char *)buff2;
 435
 436         X509_gmtime_adj(&atm,offset);
 437
 438         i=(buff1[0]-'0')*10+(buff1[1]-'0');
 439         if (i < 70) i+=100;
 440         j=(buff2[0]-'0')*10+(buff2[1]-'0');
 441         if (j < 70) j+=100;
 442
 443         if (i < j) return (-1);
 444         if (i > j) return (1);
 445         i=strcmp(buff1,buff2);
 446         if (i == 0) /* wait a second then return younger :-) */
 447                 return(-1);
 448         else
 449                 return(i);
 450         }
 451
 452 ASN1_UTCTIME *X509_gmtime_adj(s, adj)
 453 ASN1_UTCTIME *s;
 454 long adj;
 455         {
 456         time_t t;
 457
 458         time(&t);
 459         t+=adj;
 460         return(ASN1_UTCTIME_set(s,t));
 461         }
 462
 463 int X509_get_pubkey_parameters(pkey,chain)
 464 EVP_PKEY *pkey;
 465 STACK *chain;
 466         {
 467         EVP_PKEY *ktmp=NULL,*ktmp2;
 468         int i,j;
 469
 470         if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey)) return(1);
 471
 472         for (i=0; i<sk_num(chain); i++)
 473                 {
 474                 ktmp=X509_get_pubkey((X509 *)sk_value(chain,i));
 475                 if (ktmp == NULL)
 476                         {
 477                         X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
 478                         return(0);
 479                         }
 480                 if (!EVP_PKEY_missing_parameters(ktmp))
 481                         break;
 482                 else
 483                         {
 484                         ktmp=NULL;
 485                         }
 486                 }
 487         if (ktmp == NULL)
 488                 {
 489                 X509err(X509_F_X509_GET_PUBKEY_PARAMETERS,X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
 490                 return(0);
 491                 }
 492
 493         /* first, populate the other certs */
 494         for (j=i-1; j >= 0; j--)
 495                 {
 496                 ktmp2=X509_get_pubkey((X509 *)sk_value(chain,j));
 497                 EVP_PKEY_copy_parameters(ktmp2,ktmp);
 498                 }
 499
 500         if (pkey != NULL)
 501                 EVP_PKEY_copy_parameters(pkey,ktmp);
 502         return(1);
 503         }
 504
 505 EVP_PKEY *X509_get_pubkey(x)
 506 X509 *x;
 507         {
 508         return(X509_PUBKEY_get(x->cert_info->key));
 509         }
 510
 511 int X509_check_private_key(x,k)
 512 X509 *x;
 513 EVP_PKEY *k;
 514         {
 515         EVP_PKEY *xk=NULL;
 516         int ok=0;
 517
 518         xk=X509_get_pubkey(x);
 519         if (xk->type != k->type) goto err;
 520         switch (k->type)
 521                 {
 522 #ifndef NO_RSA
 523         case EVP_PKEY_RSA:
 524                 if (BN_cmp(xk->pkey.rsa->n,k->pkey.rsa->n) != 0) goto err;
 525                 if (BN_cmp(xk->pkey.rsa->e,k->pkey.rsa->e) != 0) goto err;
 526                 break;
 527 #endif
 528 #ifndef NO_DSA
 529         case EVP_PKEY_DSA:
 530                 if (BN_cmp(xk->pkey.dsa->pub_key,k->pkey.dsa->pub_key) != 0)
 531                         goto err;
 532                 break;
 533 #endif
 534 #ifndef NO_DH
 535         case EVP_PKEY_DH:
 536                 /* No idea */
 537                 goto err;
 538 #endif
 539         default:
 540                 goto err;
 541                 }
 542
 543         ok=1;
 544 err:
 545         return(ok);
 546         }
 547
 548 int X509_STORE_add_cert(ctx,x)
 549 X509_STORE *ctx;
 550 X509 *x;
 551         {
 552         X509_OBJECT *obj,*r;
 553         int ret=1;
 554
 555         if (x == NULL) return(0);
 556         obj=(X509_OBJECT *)Malloc(sizeof(X509_OBJECT));
 557         if (obj == NULL)
 558                 {
 559                 X509err(X509_F_X509_STORE_ADD_CERT,ERR_R_MALLOC_FAILURE);
 560                 return(0);
 561                 }
 562         obj->type=X509_LU_X509;
 563         obj->data.x509=x;
 564
 565         CRYPTO_w_lock(CRYPTO_LOCK_X509_STORE);
 566
 567         X509_OBJECT_up_ref_count(obj);
 568
 569         r=(X509_OBJECT *)lh_insert(ctx->certs,(char *)obj);
 570         if (r != NULL)
 571                 { /* oops, put it back */
 572                 lh_delete(ctx->certs,(char *)obj);
 573                 X509_OBJECT_free_contents(obj);
 574                 Free(obj);
 575                 lh_insert(ctx->certs,(char *)r);
 576                 X509err(X509_F_X509_STORE_ADD_CERT,X509_R_CERT_ALREADY_IN_HASH_TABLE);
 577                 ret=0;
 578                 }
 579
 580         CRYPTO_w_unlock(CRYPTO_LOCK_X509_STORE);
 581
 582         return(ret);
 583         }
 584
 585