Adam Langley | 95c29f3 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 1 | /* v3_purp.c */ |
| 2 | /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL |
| 3 | * project 2001. |
| 4 | */ |
| 5 | /* ==================================================================== |
| 6 | * Copyright (c) 1999-2004 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 | #include <stdio.h> |
| 58 | |
| 59 | #include <openssl/buf.h> |
| 60 | #include <openssl/err.h> |
| 61 | #include <openssl/digest.h> |
| 62 | #include <openssl/mem.h> |
| 63 | #include <openssl/obj.h> |
| 64 | #include <openssl/x509_vfy.h> |
| 65 | #include <openssl/x509v3.h> |
| 66 | |
| 67 | |
| 68 | static void x509v3_cache_extensions(X509 *x); |
| 69 | |
| 70 | static int check_ssl_ca(const X509 *x); |
| 71 | static int check_purpose_ssl_client(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 72 | static int check_purpose_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 73 | static int check_purpose_ns_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 74 | static int purpose_smime(const X509 *x, int ca); |
| 75 | static int check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 76 | static int check_purpose_smime_encrypt(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 77 | static int check_purpose_crl_sign(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 78 | static int check_purpose_timestamp_sign(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 79 | static int no_check(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 80 | static int ocsp_helper(const X509_PURPOSE *xp, const X509 *x, int ca); |
| 81 | |
| 82 | static int xp_cmp(const X509_PURPOSE **a, const X509_PURPOSE **b); |
| 83 | static void xptable_free(X509_PURPOSE *p); |
| 84 | |
| 85 | static X509_PURPOSE xstandard[] = { |
Adam Langley | 7351076 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 86 | {X509_PURPOSE_SSL_CLIENT, X509_TRUST_SSL_CLIENT, 0, check_purpose_ssl_client, (char *) "SSL client", (char *) "sslclient", NULL}, |
| 87 | {X509_PURPOSE_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ssl_server, (char *) "SSL server", (char *) "sslserver", NULL}, |
| 88 | {X509_PURPOSE_NS_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ns_ssl_server, (char *) "Netscape SSL server", (char *) "nssslserver", NULL}, |
| 89 | {X509_PURPOSE_SMIME_SIGN, X509_TRUST_EMAIL, 0, check_purpose_smime_sign, (char *) "S/MIME signing", (char *) "smimesign", NULL}, |
| 90 | {X509_PURPOSE_SMIME_ENCRYPT, X509_TRUST_EMAIL, 0, check_purpose_smime_encrypt, (char *) "S/MIME encryption", (char *) "smimeencrypt", NULL}, |
| 91 | {X509_PURPOSE_CRL_SIGN, X509_TRUST_COMPAT, 0, check_purpose_crl_sign, (char *) "CRL signing", (char *) "crlsign", NULL}, |
| 92 | {X509_PURPOSE_ANY, X509_TRUST_DEFAULT, 0, no_check, (char *) "Any Purpose", (char *) "any", NULL}, |
| 93 | {X509_PURPOSE_OCSP_HELPER, X509_TRUST_COMPAT, 0, ocsp_helper, (char *) "OCSP helper", (char *) "ocsphelper", NULL}, |
| 94 | {X509_PURPOSE_TIMESTAMP_SIGN, X509_TRUST_TSA, 0, check_purpose_timestamp_sign, (char *) "Time Stamp signing", (char *) "timestampsign", NULL}, |
Adam Langley | 95c29f3 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 95 | }; |
| 96 | |
| 97 | #define X509_PURPOSE_COUNT (sizeof(xstandard)/sizeof(X509_PURPOSE)) |
| 98 | |
| 99 | static STACK_OF(X509_PURPOSE) *xptable = NULL; |
| 100 | |
| 101 | static int xp_cmp(const X509_PURPOSE **a, const X509_PURPOSE **b) |
| 102 | { |
| 103 | return (*a)->purpose - (*b)->purpose; |
| 104 | } |
| 105 | |
| 106 | /* As much as I'd like to make X509_check_purpose use a "const" X509* |
| 107 | * I really can't because it does recalculate hashes and do other non-const |
| 108 | * things. */ |
| 109 | int X509_check_purpose(X509 *x, int id, int ca) |
| 110 | { |
| 111 | int idx; |
| 112 | const X509_PURPOSE *pt; |
| 113 | if(!(x->ex_flags & EXFLAG_SET)) { |
| 114 | CRYPTO_w_lock(CRYPTO_LOCK_X509); |
| 115 | x509v3_cache_extensions(x); |
| 116 | CRYPTO_w_unlock(CRYPTO_LOCK_X509); |
| 117 | } |
| 118 | if(id == -1) return 1; |
| 119 | idx = X509_PURPOSE_get_by_id(id); |
| 120 | if(idx == -1) return -1; |
| 121 | pt = X509_PURPOSE_get0(idx); |
| 122 | return pt->check_purpose(pt, x, ca); |
| 123 | } |
| 124 | |
| 125 | int X509_PURPOSE_set(int *p, int purpose) |
| 126 | { |
| 127 | if(X509_PURPOSE_get_by_id(purpose) == -1) { |
| 128 | OPENSSL_PUT_ERROR(X509V3, X509_PURPOSE_set, X509V3_R_INVALID_PURPOSE); |
| 129 | return 0; |
| 130 | } |
| 131 | *p = purpose; |
| 132 | return 1; |
| 133 | } |
| 134 | |
| 135 | int X509_PURPOSE_get_count(void) |
| 136 | { |
| 137 | if(!xptable) return X509_PURPOSE_COUNT; |
| 138 | return sk_X509_PURPOSE_num(xptable) + X509_PURPOSE_COUNT; |
| 139 | } |
| 140 | |
| 141 | X509_PURPOSE * X509_PURPOSE_get0(int idx) |
| 142 | { |
| 143 | if(idx < 0) return NULL; |
| 144 | if(idx < (int)X509_PURPOSE_COUNT) return xstandard + idx; |
| 145 | return sk_X509_PURPOSE_value(xptable, idx - X509_PURPOSE_COUNT); |
| 146 | } |
| 147 | |
| 148 | int X509_PURPOSE_get_by_sname(char *sname) |
| 149 | { |
| 150 | int i; |
| 151 | X509_PURPOSE *xptmp; |
| 152 | for(i = 0; i < X509_PURPOSE_get_count(); i++) { |
| 153 | xptmp = X509_PURPOSE_get0(i); |
| 154 | if(!strcmp(xptmp->sname, sname)) return i; |
| 155 | } |
| 156 | return -1; |
| 157 | } |
| 158 | |
| 159 | int X509_PURPOSE_get_by_id(int purpose) |
| 160 | { |
| 161 | X509_PURPOSE tmp; |
| 162 | size_t idx; |
| 163 | |
| 164 | if((purpose >= X509_PURPOSE_MIN) && (purpose <= X509_PURPOSE_MAX)) |
| 165 | return purpose - X509_PURPOSE_MIN; |
| 166 | tmp.purpose = purpose; |
| 167 | if(!xptable) return -1; |
| 168 | |
| 169 | if (!sk_X509_PURPOSE_find(xptable, &idx, &tmp)) |
| 170 | return -1; |
| 171 | return idx + X509_PURPOSE_COUNT; |
| 172 | } |
| 173 | |
| 174 | int X509_PURPOSE_add(int id, int trust, int flags, |
| 175 | int (*ck)(const X509_PURPOSE *, const X509 *, int), |
| 176 | char *name, char *sname, void *arg) |
| 177 | { |
| 178 | int idx; |
| 179 | X509_PURPOSE *ptmp; |
| 180 | /* This is set according to what we change: application can't set it */ |
| 181 | flags &= ~X509_PURPOSE_DYNAMIC; |
| 182 | /* This will always be set for application modified trust entries */ |
| 183 | flags |= X509_PURPOSE_DYNAMIC_NAME; |
| 184 | /* Get existing entry if any */ |
| 185 | idx = X509_PURPOSE_get_by_id(id); |
| 186 | /* Need a new entry */ |
| 187 | if(idx == -1) { |
| 188 | if(!(ptmp = OPENSSL_malloc(sizeof(X509_PURPOSE)))) { |
| 189 | OPENSSL_PUT_ERROR(X509V3, X509_PURPOSE_add, ERR_R_MALLOC_FAILURE); |
| 190 | return 0; |
| 191 | } |
| 192 | ptmp->flags = X509_PURPOSE_DYNAMIC; |
| 193 | } else ptmp = X509_PURPOSE_get0(idx); |
| 194 | |
| 195 | /* OPENSSL_free existing name if dynamic */ |
| 196 | if(ptmp->flags & X509_PURPOSE_DYNAMIC_NAME) { |
| 197 | OPENSSL_free(ptmp->name); |
| 198 | OPENSSL_free(ptmp->sname); |
| 199 | } |
| 200 | /* dup supplied name */ |
| 201 | ptmp->name = BUF_strdup(name); |
| 202 | ptmp->sname = BUF_strdup(sname); |
| 203 | if(!ptmp->name || !ptmp->sname) { |
| 204 | OPENSSL_PUT_ERROR(X509V3, X509_PURPOSE_add, ERR_R_MALLOC_FAILURE); |
| 205 | return 0; |
| 206 | } |
| 207 | /* Keep the dynamic flag of existing entry */ |
| 208 | ptmp->flags &= X509_PURPOSE_DYNAMIC; |
| 209 | /* Set all other flags */ |
| 210 | ptmp->flags |= flags; |
| 211 | |
| 212 | ptmp->purpose = id; |
| 213 | ptmp->trust = trust; |
| 214 | ptmp->check_purpose = ck; |
| 215 | ptmp->usr_data = arg; |
| 216 | |
| 217 | /* If its a new entry manage the dynamic table */ |
| 218 | if(idx == -1) { |
| 219 | if(!xptable && !(xptable = sk_X509_PURPOSE_new(xp_cmp))) { |
| 220 | OPENSSL_PUT_ERROR(X509V3, X509_PURPOSE_add, ERR_R_MALLOC_FAILURE); |
| 221 | return 0; |
| 222 | } |
| 223 | if (!sk_X509_PURPOSE_push(xptable, ptmp)) { |
| 224 | OPENSSL_PUT_ERROR(X509V3, X509_PURPOSE_add, ERR_R_MALLOC_FAILURE); |
| 225 | return 0; |
| 226 | } |
| 227 | } |
| 228 | return 1; |
| 229 | } |
| 230 | |
| 231 | static void xptable_free(X509_PURPOSE *p) |
| 232 | { |
| 233 | if(!p) return; |
| 234 | if (p->flags & X509_PURPOSE_DYNAMIC) |
| 235 | { |
| 236 | if (p->flags & X509_PURPOSE_DYNAMIC_NAME) { |
| 237 | OPENSSL_free(p->name); |
| 238 | OPENSSL_free(p->sname); |
| 239 | } |
| 240 | OPENSSL_free(p); |
| 241 | } |
| 242 | } |
| 243 | |
| 244 | void X509_PURPOSE_cleanup(void) |
| 245 | { |
| 246 | unsigned int i; |
| 247 | sk_X509_PURPOSE_pop_free(xptable, xptable_free); |
| 248 | for(i = 0; i < X509_PURPOSE_COUNT; i++) xptable_free(xstandard + i); |
| 249 | xptable = NULL; |
| 250 | } |
| 251 | |
| 252 | int X509_PURPOSE_get_id(X509_PURPOSE *xp) |
| 253 | { |
| 254 | return xp->purpose; |
| 255 | } |
| 256 | |
| 257 | char *X509_PURPOSE_get0_name(X509_PURPOSE *xp) |
| 258 | { |
| 259 | return xp->name; |
| 260 | } |
| 261 | |
| 262 | char *X509_PURPOSE_get0_sname(X509_PURPOSE *xp) |
| 263 | { |
| 264 | return xp->sname; |
| 265 | } |
| 266 | |
| 267 | int X509_PURPOSE_get_trust(X509_PURPOSE *xp) |
| 268 | { |
| 269 | return xp->trust; |
| 270 | } |
| 271 | |
| 272 | static int nid_cmp(const void *void_a, const void *void_b) |
| 273 | { |
| 274 | const int *a = void_a, *b = void_b; |
| 275 | |
| 276 | return *a - *b; |
| 277 | } |
| 278 | |
| 279 | int X509_supported_extension(X509_EXTENSION *ex) |
| 280 | { |
| 281 | /* This table is a list of the NIDs of supported extensions: |
| 282 | * that is those which are used by the verify process. If |
| 283 | * an extension is critical and doesn't appear in this list |
| 284 | * then the verify process will normally reject the certificate. |
| 285 | * The list must be kept in numerical order because it will be |
| 286 | * searched using bsearch. |
| 287 | */ |
| 288 | |
| 289 | static const int supported_nids[] = { |
| 290 | NID_netscape_cert_type, /* 71 */ |
| 291 | NID_key_usage, /* 83 */ |
| 292 | NID_subject_alt_name, /* 85 */ |
| 293 | NID_basic_constraints, /* 87 */ |
| 294 | NID_certificate_policies, /* 89 */ |
| 295 | NID_ext_key_usage, /* 126 */ |
| 296 | NID_policy_constraints, /* 401 */ |
| 297 | NID_proxyCertInfo, /* 663 */ |
| 298 | NID_name_constraints, /* 666 */ |
| 299 | NID_policy_mappings, /* 747 */ |
| 300 | NID_inhibit_any_policy /* 748 */ |
| 301 | }; |
| 302 | |
| 303 | int ex_nid = OBJ_obj2nid(X509_EXTENSION_get_object(ex)); |
| 304 | |
| 305 | if (ex_nid == NID_undef) |
| 306 | return 0; |
| 307 | |
| 308 | if (bsearch(&ex_nid, supported_nids, sizeof(supported_nids)/sizeof(int), sizeof(int), nid_cmp) != NULL) |
| 309 | return 1; |
| 310 | return 0; |
| 311 | } |
| 312 | |
| 313 | static void setup_dp(X509 *x, DIST_POINT *dp) |
| 314 | { |
| 315 | X509_NAME *iname = NULL; |
| 316 | size_t i; |
| 317 | if (dp->reasons) |
| 318 | { |
| 319 | if (dp->reasons->length > 0) |
| 320 | dp->dp_reasons = dp->reasons->data[0]; |
| 321 | if (dp->reasons->length > 1) |
| 322 | dp->dp_reasons |= (dp->reasons->data[1] << 8); |
| 323 | dp->dp_reasons &= CRLDP_ALL_REASONS; |
| 324 | } |
| 325 | else |
| 326 | dp->dp_reasons = CRLDP_ALL_REASONS; |
| 327 | if (!dp->distpoint || (dp->distpoint->type != 1)) |
| 328 | return; |
| 329 | for (i = 0; i < sk_GENERAL_NAME_num(dp->CRLissuer); i++) |
| 330 | { |
| 331 | GENERAL_NAME *gen = sk_GENERAL_NAME_value(dp->CRLissuer, i); |
| 332 | if (gen->type == GEN_DIRNAME) |
| 333 | { |
| 334 | iname = gen->d.directoryName; |
| 335 | break; |
| 336 | } |
| 337 | } |
| 338 | if (!iname) |
| 339 | iname = X509_get_issuer_name(x); |
| 340 | |
| 341 | DIST_POINT_set_dpname(dp->distpoint, iname); |
| 342 | |
| 343 | } |
| 344 | |
| 345 | static void setup_crldp(X509 *x) |
| 346 | { |
| 347 | size_t i; |
| 348 | x->crldp = X509_get_ext_d2i(x, NID_crl_distribution_points, NULL, NULL); |
| 349 | for (i = 0; i < sk_DIST_POINT_num(x->crldp); i++) |
| 350 | setup_dp(x, sk_DIST_POINT_value(x->crldp, i)); |
| 351 | } |
| 352 | |
| 353 | static void x509v3_cache_extensions(X509 *x) |
| 354 | { |
| 355 | BASIC_CONSTRAINTS *bs; |
| 356 | PROXY_CERT_INFO_EXTENSION *pci; |
| 357 | ASN1_BIT_STRING *usage; |
| 358 | ASN1_BIT_STRING *ns; |
| 359 | EXTENDED_KEY_USAGE *extusage; |
| 360 | X509_EXTENSION *ex; |
| 361 | size_t i; |
| 362 | int j; |
| 363 | if(x->ex_flags & EXFLAG_SET) return; |
Adam Langley | 95c29f3 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 364 | X509_digest(x, EVP_sha1(), x->sha1_hash, NULL); |
Adam Langley | 95c29f3 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 365 | /* V1 should mean no extensions ... */ |
| 366 | if(!X509_get_version(x)) x->ex_flags |= EXFLAG_V1; |
| 367 | /* Handle basic constraints */ |
| 368 | if((bs=X509_get_ext_d2i(x, NID_basic_constraints, NULL, NULL))) { |
| 369 | if(bs->ca) x->ex_flags |= EXFLAG_CA; |
| 370 | if(bs->pathlen) { |
| 371 | if((bs->pathlen->type == V_ASN1_NEG_INTEGER) |
| 372 | || !bs->ca) { |
| 373 | x->ex_flags |= EXFLAG_INVALID; |
| 374 | x->ex_pathlen = 0; |
| 375 | } else x->ex_pathlen = ASN1_INTEGER_get(bs->pathlen); |
| 376 | } else x->ex_pathlen = -1; |
| 377 | BASIC_CONSTRAINTS_free(bs); |
| 378 | x->ex_flags |= EXFLAG_BCONS; |
| 379 | } |
| 380 | /* Handle proxy certificates */ |
| 381 | if((pci=X509_get_ext_d2i(x, NID_proxyCertInfo, NULL, NULL))) { |
| 382 | if (x->ex_flags & EXFLAG_CA |
Adam Langley | 548523f | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 383 | || X509_get_ext_by_NID(x, NID_subject_alt_name, -1) >= 0 |
| 384 | || X509_get_ext_by_NID(x, NID_issuer_alt_name, -1) >= 0) { |
Adam Langley | 95c29f3 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 385 | x->ex_flags |= EXFLAG_INVALID; |
| 386 | } |
| 387 | if (pci->pcPathLengthConstraint) { |
| 388 | x->ex_pcpathlen = |
| 389 | ASN1_INTEGER_get(pci->pcPathLengthConstraint); |
| 390 | } else x->ex_pcpathlen = -1; |
| 391 | PROXY_CERT_INFO_EXTENSION_free(pci); |
| 392 | x->ex_flags |= EXFLAG_PROXY; |
| 393 | } |
| 394 | /* Handle key usage */ |
| 395 | if((usage=X509_get_ext_d2i(x, NID_key_usage, NULL, NULL))) { |
| 396 | if(usage->length > 0) { |
| 397 | x->ex_kusage = usage->data[0]; |
| 398 | if(usage->length > 1) |
| 399 | x->ex_kusage |= usage->data[1] << 8; |
| 400 | } else x->ex_kusage = 0; |
| 401 | x->ex_flags |= EXFLAG_KUSAGE; |
| 402 | ASN1_BIT_STRING_free(usage); |
| 403 | } |
| 404 | x->ex_xkusage = 0; |
| 405 | if((extusage=X509_get_ext_d2i(x, NID_ext_key_usage, NULL, NULL))) { |
| 406 | x->ex_flags |= EXFLAG_XKUSAGE; |
| 407 | for(i = 0; i < sk_ASN1_OBJECT_num(extusage); i++) { |
| 408 | switch(OBJ_obj2nid(sk_ASN1_OBJECT_value(extusage,i))) { |
| 409 | case NID_server_auth: |
| 410 | x->ex_xkusage |= XKU_SSL_SERVER; |
| 411 | break; |
| 412 | |
| 413 | case NID_client_auth: |
| 414 | x->ex_xkusage |= XKU_SSL_CLIENT; |
| 415 | break; |
| 416 | |
| 417 | case NID_email_protect: |
| 418 | x->ex_xkusage |= XKU_SMIME; |
| 419 | break; |
| 420 | |
| 421 | case NID_code_sign: |
| 422 | x->ex_xkusage |= XKU_CODE_SIGN; |
| 423 | break; |
| 424 | |
| 425 | case NID_ms_sgc: |
| 426 | case NID_ns_sgc: |
| 427 | x->ex_xkusage |= XKU_SGC; |
| 428 | break; |
| 429 | |
| 430 | case NID_OCSP_sign: |
| 431 | x->ex_xkusage |= XKU_OCSP_SIGN; |
| 432 | break; |
| 433 | |
| 434 | case NID_time_stamp: |
| 435 | x->ex_xkusage |= XKU_TIMESTAMP; |
| 436 | break; |
| 437 | |
| 438 | case NID_dvcs: |
| 439 | x->ex_xkusage |= XKU_DVCS; |
| 440 | break; |
| 441 | |
| 442 | case NID_anyExtendedKeyUsage: |
| 443 | x->ex_xkusage |= XKU_ANYEKU; |
| 444 | break; |
| 445 | } |
| 446 | } |
| 447 | sk_ASN1_OBJECT_pop_free(extusage, ASN1_OBJECT_free); |
| 448 | } |
| 449 | |
| 450 | if((ns=X509_get_ext_d2i(x, NID_netscape_cert_type, NULL, NULL))) { |
| 451 | if(ns->length > 0) x->ex_nscert = ns->data[0]; |
| 452 | else x->ex_nscert = 0; |
| 453 | x->ex_flags |= EXFLAG_NSCERT; |
| 454 | ASN1_BIT_STRING_free(ns); |
| 455 | } |
| 456 | x->skid =X509_get_ext_d2i(x, NID_subject_key_identifier, NULL, NULL); |
| 457 | x->akid =X509_get_ext_d2i(x, NID_authority_key_identifier, NULL, NULL); |
Adam Langley | a993a70 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 458 | /* Does subject name match issuer ? */ |
| 459 | if(!X509_NAME_cmp(X509_get_subject_name(x), X509_get_issuer_name(x))) |
| 460 | { |
| 461 | x->ex_flags |= EXFLAG_SI; |
| 462 | /* If SKID matches AKID also indicate self signed */ |
| 463 | if (X509_check_akid(x, x->akid) == X509_V_OK) |
| 464 | x->ex_flags |= EXFLAG_SS; |
| 465 | } |
Adam Langley | 95c29f3 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 466 | x->altname = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL); |
| 467 | x->nc = X509_get_ext_d2i(x, NID_name_constraints, &j, NULL); |
| 468 | if (!x->nc && (j != -1)) |
| 469 | x->ex_flags |= EXFLAG_INVALID; |
| 470 | setup_crldp(x); |
| 471 | |
| 472 | for (j = 0; j < X509_get_ext_count(x); j++) |
| 473 | { |
| 474 | ex = X509_get_ext(x, j); |
| 475 | if (OBJ_obj2nid(X509_EXTENSION_get_object(ex)) |
| 476 | == NID_freshest_crl) |
| 477 | x->ex_flags |= EXFLAG_FRESHEST; |
| 478 | if (!X509_EXTENSION_get_critical(ex)) |
| 479 | continue; |
| 480 | if (!X509_supported_extension(ex)) |
| 481 | { |
| 482 | x->ex_flags |= EXFLAG_CRITICAL; |
| 483 | break; |
| 484 | } |
| 485 | } |
| 486 | x->ex_flags |= EXFLAG_SET; |
| 487 | } |
| 488 | |
| 489 | /* CA checks common to all purposes |
| 490 | * return codes: |
| 491 | * 0 not a CA |
| 492 | * 1 is a CA |
| 493 | * 2 basicConstraints absent so "maybe" a CA |
| 494 | * 3 basicConstraints absent but self signed V1. |
| 495 | * 4 basicConstraints absent but keyUsage present and keyCertSign asserted. |
| 496 | */ |
| 497 | |
| 498 | #define V1_ROOT (EXFLAG_V1|EXFLAG_SS) |
| 499 | #define ku_reject(x, usage) \ |
| 500 | (((x)->ex_flags & EXFLAG_KUSAGE) && !((x)->ex_kusage & (usage))) |
| 501 | #define xku_reject(x, usage) \ |
| 502 | (((x)->ex_flags & EXFLAG_XKUSAGE) && !((x)->ex_xkusage & (usage))) |
| 503 | #define ns_reject(x, usage) \ |
| 504 | (((x)->ex_flags & EXFLAG_NSCERT) && !((x)->ex_nscert & (usage))) |
| 505 | |
| 506 | static int check_ca(const X509 *x) |
| 507 | { |
| 508 | /* keyUsage if present should allow cert signing */ |
| 509 | if(ku_reject(x, KU_KEY_CERT_SIGN)) return 0; |
| 510 | if(x->ex_flags & EXFLAG_BCONS) { |
| 511 | if(x->ex_flags & EXFLAG_CA) return 1; |
| 512 | /* If basicConstraints says not a CA then say so */ |
| 513 | else return 0; |
| 514 | } else { |
| 515 | /* we support V1 roots for... uh, I don't really know why. */ |
| 516 | if((x->ex_flags & V1_ROOT) == V1_ROOT) return 3; |
| 517 | /* If key usage present it must have certSign so tolerate it */ |
| 518 | else if (x->ex_flags & EXFLAG_KUSAGE) return 4; |
| 519 | /* Older certificates could have Netscape-specific CA types */ |
| 520 | else if (x->ex_flags & EXFLAG_NSCERT |
| 521 | && x->ex_nscert & NS_ANY_CA) return 5; |
| 522 | /* can this still be regarded a CA certificate? I doubt it */ |
| 523 | return 0; |
| 524 | } |
| 525 | } |
| 526 | |
| 527 | int X509_check_ca(X509 *x) |
| 528 | { |
| 529 | if(!(x->ex_flags & EXFLAG_SET)) { |
| 530 | CRYPTO_w_lock(CRYPTO_LOCK_X509); |
| 531 | x509v3_cache_extensions(x); |
| 532 | CRYPTO_w_unlock(CRYPTO_LOCK_X509); |
| 533 | } |
| 534 | |
| 535 | return check_ca(x); |
| 536 | } |
| 537 | |
| 538 | /* Check SSL CA: common checks for SSL client and server */ |
| 539 | static int check_ssl_ca(const X509 *x) |
| 540 | { |
| 541 | int ca_ret; |
| 542 | ca_ret = check_ca(x); |
| 543 | if(!ca_ret) return 0; |
| 544 | /* check nsCertType if present */ |
| 545 | if(ca_ret != 5 || x->ex_nscert & NS_SSL_CA) return ca_ret; |
| 546 | else return 0; |
| 547 | } |
| 548 | |
| 549 | |
| 550 | static int check_purpose_ssl_client(const X509_PURPOSE *xp, const X509 *x, int ca) |
| 551 | { |
| 552 | if(xku_reject(x,XKU_SSL_CLIENT)) return 0; |
| 553 | if(ca) return check_ssl_ca(x); |
| 554 | /* We need to do digital signatures or key agreement */ |
| 555 | if(ku_reject(x,KU_DIGITAL_SIGNATURE|KU_KEY_AGREEMENT)) return 0; |
| 556 | /* nsCertType if present should allow SSL client use */ |
| 557 | if(ns_reject(x, NS_SSL_CLIENT)) return 0; |
| 558 | return 1; |
| 559 | } |
| 560 | /* Key usage needed for TLS/SSL server: digital signature, encipherment or |
| 561 | * key agreement. The ssl code can check this more thoroughly for individual |
| 562 | * key types. |
| 563 | */ |
| 564 | #define KU_TLS \ |
| 565 | KU_DIGITAL_SIGNATURE|KU_KEY_ENCIPHERMENT|KU_KEY_AGREEMENT |
| 566 | |
| 567 | static int check_purpose_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca) |
| 568 | { |
| 569 | if(xku_reject(x,XKU_SSL_SERVER|XKU_SGC)) return 0; |
| 570 | if(ca) return check_ssl_ca(x); |
| 571 | |
| 572 | if(ns_reject(x, NS_SSL_SERVER)) return 0; |
| 573 | if(ku_reject(x, KU_TLS)) return 0; |
| 574 | |
| 575 | return 1; |
| 576 | |
| 577 | } |
| 578 | |
| 579 | static int check_purpose_ns_ssl_server(const X509_PURPOSE *xp, const X509 *x, int ca) |
| 580 | { |
| 581 | int ret; |
| 582 | ret = check_purpose_ssl_server(xp, x, ca); |
| 583 | if(!ret || ca) return ret; |
| 584 | /* We need to encipher or Netscape complains */ |
| 585 | if(ku_reject(x, KU_KEY_ENCIPHERMENT)) return 0; |
| 586 | return ret; |
| 587 | } |
| 588 | |
| 589 | /* common S/MIME checks */ |
| 590 | static int purpose_smime(const X509 *x, int ca) |
| 591 | { |
| 592 | if(xku_reject(x,XKU_SMIME)) return 0; |
| 593 | if(ca) { |
| 594 | int ca_ret; |
| 595 | ca_ret = check_ca(x); |
| 596 | if(!ca_ret) return 0; |
| 597 | /* check nsCertType if present */ |
| 598 | if(ca_ret != 5 || x->ex_nscert & NS_SMIME_CA) return ca_ret; |
| 599 | else return 0; |
| 600 | } |
| 601 | if(x->ex_flags & EXFLAG_NSCERT) { |
| 602 | if(x->ex_nscert & NS_SMIME) return 1; |
| 603 | /* Workaround for some buggy certificates */ |
| 604 | if(x->ex_nscert & NS_SSL_CLIENT) return 2; |
| 605 | return 0; |
| 606 | } |
| 607 | return 1; |
| 608 | } |
| 609 | |
| 610 | static int check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x, int ca) |
| 611 | { |
| 612 | int ret; |
| 613 | ret = purpose_smime(x, ca); |
| 614 | if(!ret || ca) return ret; |
| 615 | if(ku_reject(x, KU_DIGITAL_SIGNATURE|KU_NON_REPUDIATION)) return 0; |
| 616 | return ret; |
| 617 | } |
| 618 | |
| 619 | static int check_purpose_smime_encrypt(const X509_PURPOSE *xp, const X509 *x, int ca) |
| 620 | { |
| 621 | int ret; |
| 622 | ret = purpose_smime(x, ca); |
| 623 | if(!ret || ca) return ret; |
| 624 | if(ku_reject(x, KU_KEY_ENCIPHERMENT)) return 0; |
| 625 | return ret; |
| 626 | } |
| 627 | |
| 628 | static int check_purpose_crl_sign(const X509_PURPOSE *xp, const X509 *x, int ca) |
| 629 | { |
| 630 | if(ca) { |
| 631 | int ca_ret; |
| 632 | if((ca_ret = check_ca(x)) != 2) return ca_ret; |
| 633 | else return 0; |
| 634 | } |
| 635 | if(ku_reject(x, KU_CRL_SIGN)) return 0; |
| 636 | return 1; |
| 637 | } |
| 638 | |
| 639 | /* OCSP helper: this is *not* a full OCSP check. It just checks that |
| 640 | * each CA is valid. Additional checks must be made on the chain. |
| 641 | */ |
| 642 | |
| 643 | static int ocsp_helper(const X509_PURPOSE *xp, const X509 *x, int ca) |
| 644 | { |
| 645 | /* Must be a valid CA. Should we really support the "I don't know" |
| 646 | value (2)? */ |
| 647 | if(ca) return check_ca(x); |
| 648 | /* leaf certificate is checked in OCSP_verify() */ |
| 649 | return 1; |
| 650 | } |
| 651 | |
| 652 | static int check_purpose_timestamp_sign(const X509_PURPOSE *xp, const X509 *x, |
| 653 | int ca) |
| 654 | { |
| 655 | int i_ext; |
| 656 | |
| 657 | /* If ca is true we must return if this is a valid CA certificate. */ |
| 658 | if (ca) return check_ca(x); |
| 659 | |
| 660 | /* |
| 661 | * Check the optional key usage field: |
| 662 | * if Key Usage is present, it must be one of digitalSignature |
| 663 | * and/or nonRepudiation (other values are not consistent and shall |
| 664 | * be rejected). |
| 665 | */ |
| 666 | if ((x->ex_flags & EXFLAG_KUSAGE) |
| 667 | && ((x->ex_kusage & ~(KU_NON_REPUDIATION | KU_DIGITAL_SIGNATURE)) || |
| 668 | !(x->ex_kusage & (KU_NON_REPUDIATION | KU_DIGITAL_SIGNATURE)))) |
| 669 | return 0; |
| 670 | |
| 671 | /* Only time stamp key usage is permitted and it's required. */ |
| 672 | if (!(x->ex_flags & EXFLAG_XKUSAGE) || x->ex_xkusage != XKU_TIMESTAMP) |
| 673 | return 0; |
| 674 | |
| 675 | /* Extended Key Usage MUST be critical */ |
Adam Langley | 548523f | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 676 | i_ext = X509_get_ext_by_NID((X509 *) x, NID_ext_key_usage, -1); |
Adam Langley | 95c29f3 | 2014-06-20 12:00:00 -0700 | [diff] [blame] | 677 | if (i_ext >= 0) |
| 678 | { |
| 679 | X509_EXTENSION *ext = X509_get_ext((X509 *) x, i_ext); |
| 680 | if (!X509_EXTENSION_get_critical(ext)) |
| 681 | return 0; |
| 682 | } |
| 683 | |
| 684 | return 1; |
| 685 | } |
| 686 | |
| 687 | static int no_check(const X509_PURPOSE *xp, const X509 *x, int ca) |
| 688 | { |
| 689 | return 1; |
| 690 | } |
| 691 | |
| 692 | /* Various checks to see if one certificate issued the second. |
| 693 | * This can be used to prune a set of possible issuer certificates |
| 694 | * which have been looked up using some simple method such as by |
| 695 | * subject name. |
| 696 | * These are: |
| 697 | * 1. Check issuer_name(subject) == subject_name(issuer) |
| 698 | * 2. If akid(subject) exists check it matches issuer |
| 699 | * 3. If key_usage(issuer) exists check it supports certificate signing |
| 700 | * returns 0 for OK, positive for reason for mismatch, reasons match |
| 701 | * codes for X509_verify_cert() |
| 702 | */ |
| 703 | |
| 704 | int X509_check_issued(X509 *issuer, X509 *subject) |
| 705 | { |
| 706 | if(X509_NAME_cmp(X509_get_subject_name(issuer), |
| 707 | X509_get_issuer_name(subject))) |
| 708 | return X509_V_ERR_SUBJECT_ISSUER_MISMATCH; |
| 709 | x509v3_cache_extensions(issuer); |
| 710 | x509v3_cache_extensions(subject); |
| 711 | |
| 712 | if(subject->akid) |
| 713 | { |
| 714 | int ret = X509_check_akid(issuer, subject->akid); |
| 715 | if (ret != X509_V_OK) |
| 716 | return ret; |
| 717 | } |
| 718 | |
| 719 | if(subject->ex_flags & EXFLAG_PROXY) |
| 720 | { |
| 721 | if(ku_reject(issuer, KU_DIGITAL_SIGNATURE)) |
| 722 | return X509_V_ERR_KEYUSAGE_NO_DIGITAL_SIGNATURE; |
| 723 | } |
| 724 | else if(ku_reject(issuer, KU_KEY_CERT_SIGN)) |
| 725 | return X509_V_ERR_KEYUSAGE_NO_CERTSIGN; |
| 726 | return X509_V_OK; |
| 727 | } |
| 728 | |
| 729 | int X509_check_akid(X509 *issuer, AUTHORITY_KEYID *akid) |
| 730 | { |
| 731 | |
| 732 | if(!akid) |
| 733 | return X509_V_OK; |
| 734 | |
| 735 | /* Check key ids (if present) */ |
| 736 | if(akid->keyid && issuer->skid && |
| 737 | ASN1_OCTET_STRING_cmp(akid->keyid, issuer->skid) ) |
| 738 | return X509_V_ERR_AKID_SKID_MISMATCH; |
| 739 | /* Check serial number */ |
| 740 | if(akid->serial && |
| 741 | ASN1_INTEGER_cmp(X509_get_serialNumber(issuer), akid->serial)) |
| 742 | return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH; |
| 743 | /* Check issuer name */ |
| 744 | if(akid->issuer) |
| 745 | { |
| 746 | /* Ugh, for some peculiar reason AKID includes |
| 747 | * SEQUENCE OF GeneralName. So look for a DirName. |
| 748 | * There may be more than one but we only take any |
| 749 | * notice of the first. |
| 750 | */ |
| 751 | GENERAL_NAMES *gens; |
| 752 | GENERAL_NAME *gen; |
| 753 | X509_NAME *nm = NULL; |
| 754 | size_t i; |
| 755 | gens = akid->issuer; |
| 756 | for(i = 0; i < sk_GENERAL_NAME_num(gens); i++) |
| 757 | { |
| 758 | gen = sk_GENERAL_NAME_value(gens, i); |
| 759 | if(gen->type == GEN_DIRNAME) |
| 760 | { |
| 761 | nm = gen->d.dirn; |
| 762 | break; |
| 763 | } |
| 764 | } |
| 765 | if(nm && X509_NAME_cmp(nm, X509_get_issuer_name(issuer))) |
| 766 | return X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH; |
| 767 | } |
| 768 | return X509_V_OK; |
| 769 | } |
| 770 | |