1 /* $OpenBSD: x509_trs.c,v 1.25 2021/11/01 20:53:08 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_lcl.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 {X509_TRUST_COMPAT, 0, trust_compat, "compatible", 0, NULL},
84 {X509_TRUST_SSL_CLIENT, 0, trust_1oidany, "SSL Client", NID_client_auth, NULL},
85 {X509_TRUST_SSL_SERVER, 0, trust_1oidany, "SSL Server", NID_server_auth, NULL},
86 {X509_TRUST_EMAIL, 0, trust_1oidany, "S/MIME email", NID_email_protect, NULL},
87 {X509_TRUST_OBJECT_SIGN, 0, trust_1oidany, "Object Signer", NID_code_sign, NULL},
88 {X509_TRUST_OCSP_SIGN, 0, trust_1oid, "OCSP responder", NID_OCSP_sign, NULL},
89 {X509_TRUST_OCSP_REQUEST, 0, trust_1oid, "OCSP request", NID_ad_OCSP, NULL},
90 {X509_TRUST_TSA, 0, trust_1oidany, "TSA server", NID_time_stamp, NULL}
91 };
92
93 #define X509_TRUST_COUNT (sizeof(trstandard)/sizeof(X509_TRUST))
94
95 static STACK_OF(X509_TRUST) *trtable = NULL;
96
97 static int
tr_cmp(const X509_TRUST * const * a,const X509_TRUST * const * b)98 tr_cmp(const X509_TRUST * const *a, const X509_TRUST * const *b)
99 {
100 return (*a)->trust - (*b)->trust;
101 }
102
103 int
X509_TRUST_set_default(int (* trust)(int,X509 *,int))104 (*X509_TRUST_set_default(int (*trust)(int , X509 *, int)))(int, X509 *, int)
105 {
106 int (*oldtrust)(int , X509 *, int);
107
108 oldtrust = default_trust;
109 default_trust = trust;
110 return oldtrust;
111 }
112
113 int
X509_check_trust(X509 * x,int id,int flags)114 X509_check_trust(X509 *x, int id, int flags)
115 {
116 X509_TRUST *pt;
117 int idx;
118
119 if (id == -1)
120 return 1;
121 /*
122 * XXX beck/jsing This enables self signed certs to be trusted for
123 * an unspecified id/trust flag value (this is NOT the
124 * X509_TRUST_DEFAULT), which was the longstanding
125 * openssl behaviour. boringssl does not have this behaviour.
126 *
127 * This should be revisited, but changing the default "not default"
128 * may break things.
129 */
130 if (id == 0) {
131 int rv;
132 rv = obj_trust(NID_anyExtendedKeyUsage, x, 0);
133 if (rv != X509_TRUST_UNTRUSTED)
134 return rv;
135 return trust_compat(NULL, x, 0);
136 }
137 idx = X509_TRUST_get_by_id(id);
138 if (idx == -1)
139 return default_trust(id, x, flags);
140 pt = X509_TRUST_get0(idx);
141 return pt->check_trust(pt, x, flags);
142 }
143
144 int
X509_TRUST_get_count(void)145 X509_TRUST_get_count(void)
146 {
147 if (!trtable)
148 return X509_TRUST_COUNT;
149 return sk_X509_TRUST_num(trtable) + X509_TRUST_COUNT;
150 }
151
152 X509_TRUST *
X509_TRUST_get0(int idx)153 X509_TRUST_get0(int idx)
154 {
155 if (idx < 0)
156 return NULL;
157 if (idx < (int)X509_TRUST_COUNT)
158 return trstandard + idx;
159 return sk_X509_TRUST_value(trtable, idx - X509_TRUST_COUNT);
160 }
161
162 int
X509_TRUST_get_by_id(int id)163 X509_TRUST_get_by_id(int id)
164 {
165 X509_TRUST tmp;
166 int idx;
167
168 if ((id >= X509_TRUST_MIN) && (id <= X509_TRUST_MAX))
169 return id - X509_TRUST_MIN;
170 tmp.trust = id;
171 if (!trtable)
172 return -1;
173 idx = sk_X509_TRUST_find(trtable, &tmp);
174 if (idx == -1)
175 return -1;
176 return idx + X509_TRUST_COUNT;
177 }
178
179 int
X509_TRUST_set(int * t,int trust)180 X509_TRUST_set(int *t, int trust)
181 {
182 if (X509_TRUST_get_by_id(trust) == -1) {
183 X509error(X509_R_INVALID_TRUST);
184 return 0;
185 }
186 *t = trust;
187 return 1;
188 }
189
190 int
X509_TRUST_add(int id,int flags,int (* ck)(X509_TRUST *,X509 *,int),const char * name,int arg1,void * arg2)191 X509_TRUST_add(int id, int flags, int (*ck)(X509_TRUST *, X509 *, int),
192 const char *name, int arg1, void *arg2)
193 {
194 int idx;
195 X509_TRUST *trtmp;
196 char *name_dup;
197
198 /* This is set according to what we change: application can't set it */
199 flags &= ~X509_TRUST_DYNAMIC;
200 /* This will always be set for application modified trust entries */
201 flags |= X509_TRUST_DYNAMIC_NAME;
202 /* Get existing entry if any */
203 idx = X509_TRUST_get_by_id(id);
204 /* Need a new entry */
205 if (idx == -1) {
206 if (!(trtmp = malloc(sizeof(X509_TRUST)))) {
207 X509error(ERR_R_MALLOC_FAILURE);
208 return 0;
209 }
210 trtmp->flags = X509_TRUST_DYNAMIC;
211 } else {
212 trtmp = X509_TRUST_get0(idx);
213 if (trtmp == NULL) {
214 X509error(X509_R_INVALID_TRUST);
215 return 0;
216 }
217 }
218
219 if ((name_dup = strdup(name)) == NULL)
220 goto err;
221
222 /* free existing name if dynamic */
223 if (trtmp->flags & X509_TRUST_DYNAMIC_NAME)
224 free(trtmp->name);
225 /* dup supplied name */
226 trtmp->name = name_dup;
227 /* Keep the dynamic flag of existing entry */
228 trtmp->flags &= X509_TRUST_DYNAMIC;
229 /* Set all other flags */
230 trtmp->flags |= flags;
231
232 trtmp->trust = id;
233 trtmp->check_trust = ck;
234 trtmp->arg1 = arg1;
235 trtmp->arg2 = arg2;
236
237 /* If it's a new entry, manage the dynamic table */
238 if (idx == -1) {
239 if (trtable == NULL &&
240 (trtable = sk_X509_TRUST_new(tr_cmp)) == NULL)
241 goto err;
242 if (sk_X509_TRUST_push(trtable, trtmp) == 0)
243 goto err;
244 }
245 return 1;
246
247 err:
248 free(name_dup);
249 if (idx == -1)
250 free(trtmp);
251 X509error(ERR_R_MALLOC_FAILURE);
252 return 0;
253 }
254
255 static void
trtable_free(X509_TRUST * p)256 trtable_free(X509_TRUST *p)
257 {
258 if (!p)
259 return;
260 if (p->flags & X509_TRUST_DYNAMIC) {
261 if (p->flags & X509_TRUST_DYNAMIC_NAME)
262 free(p->name);
263 free(p);
264 }
265 }
266
267 void
X509_TRUST_cleanup(void)268 X509_TRUST_cleanup(void)
269 {
270 sk_X509_TRUST_pop_free(trtable, trtable_free);
271 trtable = NULL;
272 }
273
274 int
X509_TRUST_get_flags(const X509_TRUST * xp)275 X509_TRUST_get_flags(const X509_TRUST *xp)
276 {
277 return xp->flags;
278 }
279
280 char *
X509_TRUST_get0_name(const X509_TRUST * xp)281 X509_TRUST_get0_name(const X509_TRUST *xp)
282 {
283 return xp->name;
284 }
285
286 int
X509_TRUST_get_trust(const X509_TRUST * xp)287 X509_TRUST_get_trust(const X509_TRUST *xp)
288 {
289 return xp->trust;
290 }
291
292 static int
trust_1oidany(X509_TRUST * trust,X509 * x,int flags)293 trust_1oidany(X509_TRUST *trust, X509 *x, int flags)
294 {
295 if (x->aux && (x->aux->trust || x->aux->reject))
296 return obj_trust(trust->arg1, x, flags);
297 /* we don't have any trust settings: for compatibility
298 * we return trusted if it is self signed
299 */
300 return trust_compat(trust, x, flags);
301 }
302
303 static int
trust_1oid(X509_TRUST * trust,X509 * x,int flags)304 trust_1oid(X509_TRUST *trust, X509 *x, int flags)
305 {
306 if (x->aux)
307 return obj_trust(trust->arg1, x, flags);
308 return X509_TRUST_UNTRUSTED;
309 }
310
311 static int
trust_compat(X509_TRUST * trust,X509 * x,int flags)312 trust_compat(X509_TRUST *trust, X509 *x, int flags)
313 {
314 X509_check_purpose(x, -1, 0);
315 if (x->ex_flags & EXFLAG_SS)
316 return X509_TRUST_TRUSTED;
317 else
318 return X509_TRUST_UNTRUSTED;
319 }
320
321 static int
obj_trust(int id,X509 * x,int flags)322 obj_trust(int id, X509 *x, int flags)
323 {
324 ASN1_OBJECT *obj;
325 int i;
326 X509_CERT_AUX *ax;
327
328 ax = x->aux;
329 if (!ax)
330 return X509_TRUST_UNTRUSTED;
331 if (ax->reject) {
332 for (i = 0; i < sk_ASN1_OBJECT_num(ax->reject); i++) {
333 obj = sk_ASN1_OBJECT_value(ax->reject, i);
334 if (OBJ_obj2nid(obj) == id)
335 return X509_TRUST_REJECTED;
336 }
337 }
338 if (ax->trust) {
339 for (i = 0; i < sk_ASN1_OBJECT_num(ax->trust); i++) {
340 obj = sk_ASN1_OBJECT_value(ax->trust, i);
341 if (OBJ_obj2nid(obj) == id)
342 return X509_TRUST_TRUSTED;
343 }
344 }
345 return X509_TRUST_UNTRUSTED;
346 }
347