crypto/x509v3/v3_ncons.c

   1 /* v3_ncons.c */
   2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
   3  * project.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 2003 The OpenSSL Project.  All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in
  17  *    the documentation and/or other materials provided with the
  18  *    distribution.
  19  *
  20  * 3. All advertising materials mentioning features or use of this
  21  *    software must display the following acknowledgment:
  22  *    "This product includes software developed by the OpenSSL Project
  23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  24  *
  25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  26  *    endorse or promote products derived from this software without
  27  *    prior written permission. For written permission, please contact
  28  *    licensing@OpenSSL.org.
  29  *
  30  * 5. Products derived from this software may not be called "OpenSSL"
  31  *    nor may "OpenSSL" appear in their names without prior written
  32  *    permission of the OpenSSL Project.
  33  *
  34  * 6. Redistributions of any form whatsoever must retain the following
  35  *    acknowledgment:
  36  *    "This product includes software developed by the OpenSSL Project
  37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  38  *
  39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  50  * OF THE POSSIBILITY OF SUCH DAMAGE.
  51  * ====================================================================
  52  *
  53  * This product includes cryptographic software written by Eric Young
  54  * (eay@cryptsoft.com).  This product includes software written by Tim
  55  * Hudson (tjh@cryptsoft.com).
  56  *
  57  */
  58
  59
  60 #include <stdio.h>
  61 #include "cryptlib.h"
  62 #include <openssl/asn1t.h>
  63 #include <openssl/conf.h>
  64 #include <openssl/x509v3.h>
  65
  66 static void *v2i_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method,
  67                                   X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval);
  68 static int i2r_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method,
  69                                 void *a, BIO *bp, int ind);
  70 static int do_i2r_name_constraints(const X509V3_EXT_METHOD *method,
  71                                    STACK_OF(GENERAL_SUBTREE) *trees,
  72                                    BIO *bp, int ind, char *name);
  73 static int print_nc_ipadd(BIO *bp, ASN1_OCTET_STRING *ip);
  74
  75 static int nc_match(GENERAL_NAME *gen, NAME_CONSTRAINTS *nc);
  76 static int nc_match_single(GENERAL_NAME *sub, GENERAL_NAME *gen);
  77 static int nc_dn(X509_NAME *sub, X509_NAME *nm);
  78 static int nc_dns(ASN1_IA5STRING *sub, ASN1_IA5STRING *dns);
  79 static int nc_email(ASN1_IA5STRING *sub, ASN1_IA5STRING *eml);
  80 static int nc_uri(ASN1_IA5STRING *uri, ASN1_IA5STRING *base);
  81
  82 const X509V3_EXT_METHOD v3_name_constraints = {
  83         NID_name_constraints, 0,
  84         ASN1_ITEM_ref(NAME_CONSTRAINTS),
  85         0,0,0,0,
  86         0,0,
  87         0, v2i_NAME_CONSTRAINTS,
  88         i2r_NAME_CONSTRAINTS,0,
  89         NULL
  90 };
  91
  92 ASN1_SEQUENCE(GENERAL_SUBTREE) = {
  93         ASN1_SIMPLE(GENERAL_SUBTREE, base, GENERAL_NAME),
  94         ASN1_IMP_OPT(GENERAL_SUBTREE, minimum, ASN1_INTEGER, 0),
  95         ASN1_IMP_OPT(GENERAL_SUBTREE, maximum, ASN1_INTEGER, 1)
  96 } ASN1_SEQUENCE_END(GENERAL_SUBTREE)
  97
  98 ASN1_SEQUENCE(NAME_CONSTRAINTS) = {
  99         ASN1_IMP_SEQUENCE_OF_OPT(NAME_CONSTRAINTS, permittedSubtrees,
 100                                                         GENERAL_SUBTREE, 0),
 101         ASN1_IMP_SEQUENCE_OF_OPT(NAME_CONSTRAINTS, excludedSubtrees,
 102                                                         GENERAL_SUBTREE, 1),
 103 } ASN1_SEQUENCE_END(NAME_CONSTRAINTS)
 104
 105
 106 IMPLEMENT_ASN1_ALLOC_FUNCTIONS(GENERAL_SUBTREE)
 107 IMPLEMENT_ASN1_ALLOC_FUNCTIONS(NAME_CONSTRAINTS)
 108
 109 static void *v2i_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method,
 110                                   X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval)
 111         {
 112         int i;
 113         CONF_VALUE tval, *val;
 114         STACK_OF(GENERAL_SUBTREE) **ptree = NULL;
 115         NAME_CONSTRAINTS *ncons = NULL;
 116         GENERAL_SUBTREE *sub = NULL;
 117         ncons = NAME_CONSTRAINTS_new();
 118         if (!ncons)
 119                 goto memerr;
 120         for(i = 0; i < sk_CONF_VALUE_num(nval); i++)
 121                 {
 122                 val = sk_CONF_VALUE_value(nval, i);
 123                 if (!strncmp(val->name, "permitted", 9) && val->name[9])
 124                         {
 125                         ptree = &ncons->permittedSubtrees;
 126                         tval.name = val->name + 10;
 127                         }
 128                 else if (!strncmp(val->name, "excluded", 8) && val->name[8])
 129                         {
 130                         ptree = &ncons->excludedSubtrees;
 131                         tval.name = val->name + 9;
 132                         }
 133                 else
 134                         {
 135                         X509V3err(X509V3_F_V2I_NAME_CONSTRAINTS, X509V3_R_INVALID_SYNTAX);
 136                         goto err;
 137                         }
 138                 tval.value = val->value;
 139                 sub = GENERAL_SUBTREE_new();
 140                 if (!v2i_GENERAL_NAME_ex(sub->base, method, ctx, &tval, 1))
 141                         goto err;
 142                 if (!*ptree)
 143                         *ptree = sk_GENERAL_SUBTREE_new_null();
 144                 if (!*ptree || !sk_GENERAL_SUBTREE_push(*ptree, sub))
 145                         goto memerr;
 146                 sub = NULL;
 147                 }
 148
 149         return ncons;
 150
 151         memerr:
 152         X509V3err(X509V3_F_V2I_NAME_CONSTRAINTS, ERR_R_MALLOC_FAILURE);
 153         err:
 154         if (ncons)
 155                 NAME_CONSTRAINTS_free(ncons);
 156         if (sub)
 157                 GENERAL_SUBTREE_free(sub);
 158
 159         return NULL;
 160         }
 161
 162
 163
 164
 165 static int i2r_NAME_CONSTRAINTS(const X509V3_EXT_METHOD *method, void *a,
 166                                 BIO *bp, int ind)
 167         {
 168         NAME_CONSTRAINTS *ncons = a;
 169         do_i2r_name_constraints(method, ncons->permittedSubtrees,
 170                                         bp, ind, "Permitted");
 171         do_i2r_name_constraints(method, ncons->excludedSubtrees,
 172                                         bp, ind, "Excluded");
 173         return 1;
 174         }
 175
 176 static int do_i2r_name_constraints(const X509V3_EXT_METHOD *method,
 177                                    STACK_OF(GENERAL_SUBTREE) *trees,
 178                                    BIO *bp, int ind, char *name)
 179         {
 180         GENERAL_SUBTREE *tree;
 181         int i;
 182         if (sk_GENERAL_SUBTREE_num(trees) > 0)
 183                 BIO_printf(bp, "%*s%s:\n", ind, "", name);
 184         for(i = 0; i < sk_GENERAL_SUBTREE_num(trees); i++)
 185                 {
 186                 tree = sk_GENERAL_SUBTREE_value(trees, i);
 187                 BIO_printf(bp, "%*s", ind + 2, "");
 188                 if (tree->base->type == GEN_IPADD)
 189                         print_nc_ipadd(bp, tree->base->d.ip);
 190                 else
 191                         GENERAL_NAME_print(bp, tree->base);
 192                 tree = sk_GENERAL_SUBTREE_value(trees, i);
 193                 BIO_puts(bp, "\n");
 194                 }
 195         return 1;
 196         }
 197
 198 static int print_nc_ipadd(BIO *bp, ASN1_OCTET_STRING *ip)
 199         {
 200         int i, len;
 201         unsigned char *p;
 202         p = ip->data;
 203         len = ip->length;
 204         BIO_puts(bp, "IP:");
 205         if(len == 8)
 206                 {
 207                 BIO_printf(bp, "%d.%d.%d.%d/%d.%d.%d.%d",
 208                                 p[0], p[1], p[2], p[3],
 209                                 p[4], p[5], p[6], p[7]);
 210                 }
 211         else if(len == 32)
 212                 {
 213                 for (i = 0; i < 16; i++)
 214                         {
 215                         BIO_printf(bp, "%X", p[0] << 8 | p[1]);
 216                         p += 2;
 217                         if (i == 7)
 218                                 BIO_puts(bp, "/");
 219                         else if (i != 15)
 220                                 BIO_puts(bp, ":");
 221                         }
 222                 }
 223         else
 224                 BIO_printf(bp, "IP Address:<invalid>");
 225         return 1;
 226         }
 227
 228 /* Check a certificate conforms to a specified set of constraints.
 229  * Return values:
 230  *  X509_V_OK: All constraints obeyed.
 231  *  X509_V_ERR_PERMITTED_VIOLATION: Permitted subtree violation.
 232  *  X509_V_ERR_EXCLUDED_VIOLATION: Excluded subtree violation.
 233  *  X509_V_ERR_SUBTREE_MINMAX: Min or max values present and matching type.
 234  *  X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE:  Unsupported constraint type.
 235  *  X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX: bad unsupported constraint syntax.
 236  *  X509_V_ERR_UNSUPPORTED_NAME_SYNTAX: bad or unsupported syntax of name
 237
 238  */
 239
 240 int NAME_CONSTRAINTS_check(X509 *x, NAME_CONSTRAINTS *nc)
 241         {
 242         int r, i;
 243         X509_NAME *nm;
 244
 245         nm = X509_get_subject_name(x);
 246
 247         if (X509_NAME_entry_count(nm) > 0)
 248                 {
 249                 GENERAL_NAME gntmp;
 250                 gntmp.type = GEN_DIRNAME;
 251                 gntmp.d.directoryName = nm;
 252
 253                 r = nc_match(&gntmp, nc);
 254
 255                 if (r != X509_V_OK)
 256                         return r;
 257
 258                 gntmp.type = GEN_EMAIL;
 259
 260
 261                 /* Process any email address attributes in subject name */
 262
 263                 for (i = -1;;)
 264                         {
 265                         X509_NAME_ENTRY *ne;
 266                         i = X509_NAME_get_index_by_NID(nm,
 267                                                        NID_pkcs9_emailAddress,
 268                                                        i);
 269                         if (i == -1)
 270                                 break;
 271                         ne = X509_NAME_get_entry(nm, i);
 272                         gntmp.d.rfc822Name = X509_NAME_ENTRY_get_data(ne);
 273                         if (gntmp.d.rfc822Name->type != V_ASN1_IA5STRING)
 274                                 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
 275
 276                         r = nc_match(&gntmp, nc);
 277
 278                         if (r != X509_V_OK)
 279                                 return r;
 280                         }
 281
 282                 }
 283
 284         for (i = 0; i < sk_GENERAL_NAME_num(x->altname); i++)
 285                 {
 286                 GENERAL_NAME *gen = sk_GENERAL_NAME_value(x->altname, i);
 287                 r = nc_match(gen, nc);
 288                 if (r != X509_V_OK)
 289                         return r;
 290                 }
 291
 292         return X509_V_OK;
 293
 294         }
 295
 296 static int nc_match(GENERAL_NAME *gen, NAME_CONSTRAINTS *nc)
 297         {
 298         GENERAL_SUBTREE *sub;
 299         int i, r, match = 0;
 300
 301         /* Permitted subtrees: if any subtrees exist of matching the type
 302          * at least one subtree must match.
 303          */
 304
 305         for (i = 0; i < sk_GENERAL_SUBTREE_num(nc->permittedSubtrees); i++)
 306                 {
 307                 sub = sk_GENERAL_SUBTREE_value(nc->permittedSubtrees, i);
 308                 if (gen->type != sub->base->type)
 309                         continue;
 310                 if (sub->minimum || sub->maximum)
 311                         return X509_V_ERR_SUBTREE_MINMAX;
 312                 /* If we already have a match don't bother trying any more */
 313                 if (match == 2)
 314                         continue;
 315                 if (match == 0)
 316                         match = 1;
 317                 r = nc_match_single(gen, sub->base);
 318                 if (r == X509_V_OK)
 319                         match = 2;
 320                 else if (r != X509_V_ERR_PERMITTED_VIOLATION)
 321                         return r;
 322                 }
 323
 324         if (match == 1)
 325                 return X509_V_ERR_PERMITTED_VIOLATION;
 326
 327         /* Excluded subtrees: must not match any of these */
 328
 329         for (i = 0; i < sk_GENERAL_SUBTREE_num(nc->excludedSubtrees); i++)
 330                 {
 331                 sub = sk_GENERAL_SUBTREE_value(nc->excludedSubtrees, i);
 332                 if (gen->type != sub->base->type)
 333                         continue;
 334                 if (sub->minimum || sub->maximum)
 335                         return X509_V_ERR_SUBTREE_MINMAX;
 336
 337                 r = nc_match_single(gen, sub->base);
 338                 if (r == X509_V_OK)
 339                         return X509_V_ERR_EXCLUDED_VIOLATION;
 340                 else if (r != X509_V_ERR_PERMITTED_VIOLATION)
 341                         return r;
 342
 343                 }
 344
 345         return X509_V_OK;
 346
 347         }
 348
 349 static int nc_match_single(GENERAL_NAME *gen, GENERAL_NAME *base)
 350         {
 351         switch(base->type)
 352                 {
 353                 case GEN_DIRNAME:
 354                 return nc_dn(gen->d.directoryName, base->d.directoryName);
 355
 356                 case GEN_DNS:
 357                 return nc_dns(gen->d.dNSName, base->d.dNSName);
 358
 359                 case GEN_EMAIL:
 360                 return nc_email(gen->d.rfc822Name, base->d.rfc822Name);
 361
 362                 case GEN_URI:
 363                 return nc_uri(gen->d.uniformResourceIdentifier,
 364                                         base->d.uniformResourceIdentifier);
 365
 366                 default:
 367                 return X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE;
 368                 }
 369
 370         }
 371
 372 /* directoryName name constraint matching.
 373  * The canonical encoding of X509_NAME makes this comparison easy. It is
 374  * matched if the subtree is a subset of the name.
 375  */
 376
 377 static int nc_dn(X509_NAME *nm, X509_NAME *base)
 378         {
 379         /* Ensure canonical encodings are up to date.  */
 380         if (nm->modified && i2d_X509_NAME(nm, NULL) < 0)
 381                 return X509_V_ERR_OUT_OF_MEM;
 382         if (base->modified && i2d_X509_NAME(base, NULL) < 0)
 383                 return X509_V_ERR_OUT_OF_MEM;
 384         if (base->canon_enclen > nm->canon_enclen)
 385                 return X509_V_ERR_PERMITTED_VIOLATION;
 386         if (memcmp(base->canon_enc, nm->canon_enc, base->canon_enclen))
 387                 return X509_V_ERR_PERMITTED_VIOLATION;
 388         return X509_V_OK;
 389         }
 390
 391 static int nc_dns(ASN1_IA5STRING *dns, ASN1_IA5STRING *base)
 392         {
 393         char *baseptr = (char *)base->data;
 394         char *dnsptr = (char *)dns->data;
 395         /* Empty matches everything */
 396         if (!*baseptr)
 397                 return X509_V_OK;
 398         /* Otherwise can add zero or more components on the left so
 399          * compare RHS and if dns is longer and expect '.' as preceding
 400          * character.
 401          */
 402         if (dns->length > base->length)
 403                 {
 404                 dnsptr += dns->length - base->length;
 405                 if (dnsptr[-1] != '.')
 406                         return X509_V_ERR_PERMITTED_VIOLATION;
 407                 }
 408
 409         if (strcasecmp(baseptr, dnsptr))
 410                         return X509_V_ERR_PERMITTED_VIOLATION;
 411
 412         return X509_V_OK;
 413
 414         }
 415
 416 static int nc_email(ASN1_IA5STRING *eml, ASN1_IA5STRING *base)
 417         {
 418         const char *baseptr = (char *)base->data;
 419         const char *emlptr = (char *)eml->data;
 420
 421         const char *baseat = strchr(baseptr, '@');
 422         const char *emlat = strchr(emlptr, '@');
 423         if (!emlat)
 424                 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
 425         /* Special case: inital '.' is RHS match */
 426         if (!baseat && (*baseptr == '.'))
 427                 {
 428                 if (eml->length > base->length)
 429                         {
 430                         emlptr += eml->length - base->length;
 431                         if (!strcasecmp(baseptr, emlptr))
 432                                 return X509_V_OK;
 433                         }
 434                 return X509_V_ERR_PERMITTED_VIOLATION;
 435                 }
 436
 437         /* If we have anything before '@' match local part */
 438
 439         if (baseat)
 440                 {
 441                 if (baseat != baseptr)
 442                         {
 443                         if ((baseat - baseptr) != (emlat - emlptr))
 444                                 return X509_V_ERR_PERMITTED_VIOLATION;
 445                         /* Case sensitive match of local part */
 446                         if (strncmp(baseptr, emlptr, emlat - emlptr))
 447                                 return X509_V_ERR_PERMITTED_VIOLATION;
 448                         }
 449                 /* Position base after '@' */
 450                 baseptr = baseat + 1;
 451                 }
 452         emlptr = emlat + 1;
 453         /* Just have hostname left to match: case insensitive */
 454         if (strcasecmp(baseptr, emlptr))
 455                 return X509_V_ERR_PERMITTED_VIOLATION;
 456
 457         return X509_V_OK;
 458
 459         }
 460
 461 static int nc_uri(ASN1_IA5STRING *uri, ASN1_IA5STRING *base)
 462         {
 463         const char *baseptr = (char *)base->data;
 464         const char *hostptr = (char *)uri->data;
 465         const char *p = strchr(hostptr, ':');
 466         int hostlen;
 467         /* Check for foo:// and skip past it */
 468         if (!p || (p[1] != '/') || (p[2] != '/'))
 469                 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
 470         hostptr = p + 3;
 471
 472         /* Determine length of hostname part of URI */
 473
 474         /* Look for a port indicator as end of hostname first */
 475
 476         p = strchr(hostptr, ':');
 477         /* Otherwise look for trailing slash */
 478         if (!p)
 479                 p = strchr(hostptr, '/');
 480
 481         if (!p)
 482                 hostlen = strlen(hostptr);
 483         else
 484                 hostlen = p - hostptr;
 485
 486         if (hostlen == 0)
 487                 return X509_V_ERR_UNSUPPORTED_NAME_SYNTAX;
 488
 489         /* Special case: inital '.' is RHS match */
 490         if (*baseptr == '.')
 491                 {
 492                 if (hostlen > base->length)
 493                         {
 494                         p = hostptr + hostlen - base->length;
 495                         if (!strncasecmp(p, baseptr, base->length))
 496                                 return X509_V_OK;
 497                         }
 498                 return X509_V_ERR_PERMITTED_VIOLATION;
 499                 }
 500
 501         if ((base->length != (int)hostlen) || strncasecmp(hostptr, baseptr, hostlen))
 502                 return X509_V_ERR_PERMITTED_VIOLATION;
 503
 504         return X509_V_OK;
 505
 506         }