1 /* $OpenBSD: x509_trs.c,v 1.32 2023/07/02 17:12:17 tb Exp $ */ 2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL 3 * project 1999. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 1999 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 #include <stdio.h> 60 #include <string.h> 61 62 #include <openssl/err.h> 63 #include <openssl/x509v3.h> 64 65 #include "x509_local.h" 66 67 static int tr_cmp(const X509_TRUST * const *a, const X509_TRUST * const *b); 68 static void trtable_free(X509_TRUST *p); 69 70 static int trust_1oidany(X509_TRUST *trust, X509 *x, int flags); 71 static int trust_1oid(X509_TRUST *trust, X509 *x, int flags); 72 static int trust_compat(X509_TRUST *trust, X509 *x, int flags); 73 74 static int obj_trust(int id, X509 *x, int flags); 75 static int (*default_trust)(int id, X509 *x, int flags) = obj_trust; 76 77 /* WARNING: the following table should be kept in order of trust 78 * and without any gaps so we can just subtract the minimum trust 79 * value to get an index into the table 80 */ 81 82 static X509_TRUST trstandard[] = { 83 { 84 .trust = X509_TRUST_COMPAT, 85 .check_trust = trust_compat, 86 .name = "compatible", 87 }, 88 { 89 .trust = X509_TRUST_SSL_CLIENT, 90 .check_trust = trust_1oidany, 91 .name = "SSL Client", 92 .arg1 = NID_client_auth, 93 }, 94 { 95 .trust = X509_TRUST_SSL_SERVER, 96 .check_trust = trust_1oidany, 97 .name = "SSL Server", 98 .arg1 = NID_server_auth, 99 }, 100 { 101 .trust = X509_TRUST_EMAIL, 102 .check_trust = trust_1oidany, 103 .name = "S/MIME email", 104 .arg1 = NID_email_protect, 105 }, 106 { 107 .trust = X509_TRUST_OBJECT_SIGN, 108 .check_trust = trust_1oidany, 109 .name = "Object Signer", 110 .arg1 = NID_code_sign, 111 }, 112 { 113 .trust = X509_TRUST_OCSP_SIGN, 114 .check_trust = trust_1oid, 115 .name = "OCSP responder", 116 .arg1 = NID_OCSP_sign, 117 }, 118 { 119 .trust = X509_TRUST_OCSP_REQUEST, 120 .check_trust = trust_1oid, 121 .name = "OCSP request", 122 .arg1 = NID_ad_OCSP, 123 }, 124 { 125 .trust = X509_TRUST_TSA, 126 .check_trust = trust_1oidany, 127 .name = "TSA server", 128 .arg1 = NID_time_stamp, 129 }, 130 }; 131 132 #define X509_TRUST_COUNT (sizeof(trstandard) / sizeof(trstandard[0])) 133 134 static STACK_OF(X509_TRUST) *trtable = NULL; 135 136 static int 137 tr_cmp(const X509_TRUST * const *a, const X509_TRUST * const *b) 138 { 139 return (*a)->trust - (*b)->trust; 140 } 141 142 int 143 (*X509_TRUST_set_default(int (*trust)(int , X509 *, int)))(int, X509 *, int) 144 { 145 int (*oldtrust)(int , X509 *, int); 146 147 oldtrust = default_trust; 148 default_trust = trust; 149 return oldtrust; 150 } 151 LCRYPTO_ALIAS(X509_TRUST_set_default); 152 153 int 154 X509_check_trust(X509 *x, int id, int flags) 155 { 156 X509_TRUST *pt; 157 int idx; 158 159 if (id == -1) 160 return 1; 161 /* 162 * XXX beck/jsing This enables self signed certs to be trusted for 163 * an unspecified id/trust flag value (this is NOT the 164 * X509_TRUST_DEFAULT), which was the longstanding 165 * openssl behaviour. boringssl does not have this behaviour. 166 * 167 * This should be revisited, but changing the default "not default" 168 * may break things. 169 */ 170 if (id == 0) { 171 int rv; 172 rv = obj_trust(NID_anyExtendedKeyUsage, x, 0); 173 if (rv != X509_TRUST_UNTRUSTED) 174 return rv; 175 return trust_compat(NULL, x, 0); 176 } 177 idx = X509_TRUST_get_by_id(id); 178 if (idx == -1) 179 return default_trust(id, x, flags); 180 pt = X509_TRUST_get0(idx); 181 return pt->check_trust(pt, x, flags); 182 } 183 LCRYPTO_ALIAS(X509_check_trust); 184 185 int 186 X509_TRUST_get_count(void) 187 { 188 if (!trtable) 189 return X509_TRUST_COUNT; 190 return sk_X509_TRUST_num(trtable) + X509_TRUST_COUNT; 191 } 192 LCRYPTO_ALIAS(X509_TRUST_get_count); 193 194 X509_TRUST * 195 X509_TRUST_get0(int idx) 196 { 197 if (idx < 0) 198 return NULL; 199 if (idx < (int)X509_TRUST_COUNT) 200 return trstandard + idx; 201 return sk_X509_TRUST_value(trtable, idx - X509_TRUST_COUNT); 202 } 203 LCRYPTO_ALIAS(X509_TRUST_get0); 204 205 int 206 X509_TRUST_get_by_id(int id) 207 { 208 X509_TRUST tmp; 209 int idx; 210 211 if ((id >= X509_TRUST_MIN) && (id <= X509_TRUST_MAX)) 212 return id - X509_TRUST_MIN; 213 tmp.trust = id; 214 if (!trtable) 215 return -1; 216 idx = sk_X509_TRUST_find(trtable, &tmp); 217 if (idx == -1) 218 return -1; 219 return idx + X509_TRUST_COUNT; 220 } 221 LCRYPTO_ALIAS(X509_TRUST_get_by_id); 222 223 int 224 X509_TRUST_set(int *t, int trust) 225 { 226 if (X509_TRUST_get_by_id(trust) == -1) { 227 X509error(X509_R_INVALID_TRUST); 228 return 0; 229 } 230 *t = trust; 231 return 1; 232 } 233 LCRYPTO_ALIAS(X509_TRUST_set); 234 235 int 236 X509_TRUST_add(int id, int flags, int (*ck)(X509_TRUST *, X509 *, int), 237 const char *name, int arg1, void *arg2) 238 { 239 int idx; 240 X509_TRUST *trtmp; 241 char *name_dup; 242 243 /* This is set according to what we change: application can't set it */ 244 flags &= ~X509_TRUST_DYNAMIC; 245 /* This will always be set for application modified trust entries */ 246 flags |= X509_TRUST_DYNAMIC_NAME; 247 /* Get existing entry if any */ 248 idx = X509_TRUST_get_by_id(id); 249 /* Need a new entry */ 250 if (idx == -1) { 251 if (!(trtmp = malloc(sizeof(X509_TRUST)))) { 252 X509error(ERR_R_MALLOC_FAILURE); 253 return 0; 254 } 255 trtmp->flags = X509_TRUST_DYNAMIC; 256 } else { 257 trtmp = X509_TRUST_get0(idx); 258 if (trtmp == NULL) { 259 X509error(X509_R_INVALID_TRUST); 260 return 0; 261 } 262 } 263 264 if ((name_dup = strdup(name)) == NULL) 265 goto err; 266 267 /* free existing name if dynamic */ 268 if (trtmp->flags & X509_TRUST_DYNAMIC_NAME) 269 free(trtmp->name); 270 /* dup supplied name */ 271 trtmp->name = name_dup; 272 /* Keep the dynamic flag of existing entry */ 273 trtmp->flags &= X509_TRUST_DYNAMIC; 274 /* Set all other flags */ 275 trtmp->flags |= flags; 276 277 trtmp->trust = id; 278 trtmp->check_trust = ck; 279 trtmp->arg1 = arg1; 280 trtmp->arg2 = arg2; 281 282 /* If it's a new entry, manage the dynamic table */ 283 if (idx == -1) { 284 if (trtable == NULL && 285 (trtable = sk_X509_TRUST_new(tr_cmp)) == NULL) 286 goto err; 287 if (sk_X509_TRUST_push(trtable, trtmp) == 0) 288 goto err; 289 } 290 return 1; 291 292 err: 293 free(name_dup); 294 if (idx == -1) 295 free(trtmp); 296 X509error(ERR_R_MALLOC_FAILURE); 297 return 0; 298 } 299 LCRYPTO_ALIAS(X509_TRUST_add); 300 301 static void 302 trtable_free(X509_TRUST *p) 303 { 304 if (!p) 305 return; 306 if (p->flags & X509_TRUST_DYNAMIC) { 307 if (p->flags & X509_TRUST_DYNAMIC_NAME) 308 free(p->name); 309 free(p); 310 } 311 } 312 313 void 314 X509_TRUST_cleanup(void) 315 { 316 sk_X509_TRUST_pop_free(trtable, trtable_free); 317 trtable = NULL; 318 } 319 LCRYPTO_ALIAS(X509_TRUST_cleanup); 320 321 int 322 X509_TRUST_get_flags(const X509_TRUST *xp) 323 { 324 return xp->flags; 325 } 326 LCRYPTO_ALIAS(X509_TRUST_get_flags); 327 328 char * 329 X509_TRUST_get0_name(const X509_TRUST *xp) 330 { 331 return xp->name; 332 } 333 LCRYPTO_ALIAS(X509_TRUST_get0_name); 334 335 int 336 X509_TRUST_get_trust(const X509_TRUST *xp) 337 { 338 return xp->trust; 339 } 340 LCRYPTO_ALIAS(X509_TRUST_get_trust); 341 342 static int 343 trust_1oidany(X509_TRUST *trust, X509 *x, int flags) 344 { 345 if (x->aux && (x->aux->trust || x->aux->reject)) 346 return obj_trust(trust->arg1, x, flags); 347 /* we don't have any trust settings: for compatibility 348 * we return trusted if it is self signed 349 */ 350 return trust_compat(trust, x, flags); 351 } 352 353 static int 354 trust_1oid(X509_TRUST *trust, X509 *x, int flags) 355 { 356 if (x->aux) 357 return obj_trust(trust->arg1, x, flags); 358 return X509_TRUST_UNTRUSTED; 359 } 360 361 static int 362 trust_compat(X509_TRUST *trust, X509 *x, int flags) 363 { 364 X509_check_purpose(x, -1, 0); 365 if (x->ex_flags & EXFLAG_SS) 366 return X509_TRUST_TRUSTED; 367 else 368 return X509_TRUST_UNTRUSTED; 369 } 370 371 static int 372 obj_trust(int id, X509 *x, int flags) 373 { 374 ASN1_OBJECT *obj; 375 int i, nid; 376 X509_CERT_AUX *ax; 377 378 ax = x->aux; 379 if (!ax) 380 return X509_TRUST_UNTRUSTED; 381 if (ax->reject) { 382 for (i = 0; i < sk_ASN1_OBJECT_num(ax->reject); i++) { 383 obj = sk_ASN1_OBJECT_value(ax->reject, i); 384 nid = OBJ_obj2nid(obj); 385 if (nid == id || nid == NID_anyExtendedKeyUsage) 386 return X509_TRUST_REJECTED; 387 } 388 } 389 if (ax->trust) { 390 for (i = 0; i < sk_ASN1_OBJECT_num(ax->trust); i++) { 391 obj = sk_ASN1_OBJECT_value(ax->trust, i); 392 nid = OBJ_obj2nid(obj); 393 if (nid == id || nid == NID_anyExtendedKeyUsage) 394 return X509_TRUST_TRUSTED; 395 } 396 } 397 return X509_TRUST_UNTRUSTED; 398 } 399