1 /* $OpenBSD: x509_trs.c,v 1.19 2014/12/06 19:26:37 doug 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 static int tr_cmp(const X509_TRUST * const *a, const X509_TRUST * const *b);
66 static void trtable_free(X509_TRUST *p);
67 
68 static int trust_1oidany(X509_TRUST *trust, X509 *x, int flags);
69 static int trust_1oid(X509_TRUST *trust, X509 *x, int flags);
70 static int trust_compat(X509_TRUST *trust, X509 *x, int flags);
71 
72 static int obj_trust(int id, X509 *x, int flags);
73 static int (*default_trust)(int id, X509 *x, int flags) = obj_trust;
74 
75 /* WARNING: the following table should be kept in order of trust
76  * and without any gaps so we can just subtract the minimum trust
77  * value to get an index into the table
78  */
79 
80 static X509_TRUST trstandard[] = {
81 	{X509_TRUST_COMPAT, 0, trust_compat, "compatible", 0, NULL},
82 	{X509_TRUST_SSL_CLIENT, 0, trust_1oidany, "SSL Client", NID_client_auth, NULL},
83 	{X509_TRUST_SSL_SERVER, 0, trust_1oidany, "SSL Server", NID_server_auth, NULL},
84 	{X509_TRUST_EMAIL, 0, trust_1oidany, "S/MIME email", NID_email_protect, NULL},
85 	{X509_TRUST_OBJECT_SIGN, 0, trust_1oidany, "Object Signer", NID_code_sign, NULL},
86 	{X509_TRUST_OCSP_SIGN, 0, trust_1oid, "OCSP responder", NID_OCSP_sign, NULL},
87 	{X509_TRUST_OCSP_REQUEST, 0, trust_1oid, "OCSP request", NID_ad_OCSP, NULL},
88 	{X509_TRUST_TSA, 0, trust_1oidany, "TSA server", NID_time_stamp, NULL}
89 };
90 
91 #define X509_TRUST_COUNT	(sizeof(trstandard)/sizeof(X509_TRUST))
92 
93 static STACK_OF(X509_TRUST) *trtable = NULL;
94 
95 static int
96 tr_cmp(const X509_TRUST * const *a, const X509_TRUST * const *b)
97 {
98 	return (*a)->trust - (*b)->trust;
99 }
100 
101 int
102 (*X509_TRUST_set_default(int (*trust)(int , X509 *, int)))(int, X509 *, int)
103 {
104 	int (*oldtrust)(int , X509 *, int);
105 
106 	oldtrust = default_trust;
107 	default_trust = trust;
108 	return oldtrust;
109 }
110 
111 int
112 X509_check_trust(X509 *x, int id, int flags)
113 {
114 	X509_TRUST *pt;
115 	int idx;
116 
117 	if (id == -1)
118 		return 1;
119 	idx = X509_TRUST_get_by_id(id);
120 	if (idx == -1)
121 		return default_trust(id, x, flags);
122 	pt = X509_TRUST_get0(idx);
123 	return pt->check_trust(pt, x, flags);
124 }
125 
126 int
127 X509_TRUST_get_count(void)
128 {
129 	if (!trtable)
130 		return X509_TRUST_COUNT;
131 	return sk_X509_TRUST_num(trtable) + X509_TRUST_COUNT;
132 }
133 
134 X509_TRUST *
135 X509_TRUST_get0(int idx)
136 {
137 	if (idx < 0)
138 		return NULL;
139 	if (idx < (int)X509_TRUST_COUNT)
140 		return trstandard + idx;
141 	return sk_X509_TRUST_value(trtable, idx - X509_TRUST_COUNT);
142 }
143 
144 int
145 X509_TRUST_get_by_id(int id)
146 {
147 	X509_TRUST tmp;
148 	int idx;
149 
150 	if ((id >= X509_TRUST_MIN) && (id <= X509_TRUST_MAX))
151 		return id - X509_TRUST_MIN;
152 	tmp.trust = id;
153 	if (!trtable)
154 		return -1;
155 	idx = sk_X509_TRUST_find(trtable, &tmp);
156 	if (idx == -1)
157 		return -1;
158 	return idx + X509_TRUST_COUNT;
159 }
160 
161 int
162 X509_TRUST_set(int *t, int trust)
163 {
164 	if (X509_TRUST_get_by_id(trust) == -1) {
165 		X509err(X509_F_X509_TRUST_SET, X509_R_INVALID_TRUST);
166 		return 0;
167 	}
168 	*t = trust;
169 	return 1;
170 }
171 
172 int
173 X509_TRUST_add(int id, int flags, int (*ck)(X509_TRUST *, X509 *, int),
174     char *name, int arg1, void *arg2)
175 {
176 	int idx;
177 	X509_TRUST *trtmp;
178 	char *name_dup;
179 
180 	/* This is set according to what we change: application can't set it */
181 	flags &= ~X509_TRUST_DYNAMIC;
182 	/* This will always be set for application modified trust entries */
183 	flags |= X509_TRUST_DYNAMIC_NAME;
184 	/* Get existing entry if any */
185 	idx = X509_TRUST_get_by_id(id);
186 	/* Need a new entry */
187 	if (idx == -1) {
188 		if (!(trtmp = malloc(sizeof(X509_TRUST)))) {
189 			X509err(X509_F_X509_TRUST_ADD, ERR_R_MALLOC_FAILURE);
190 			return 0;
191 		}
192 		trtmp->flags = X509_TRUST_DYNAMIC;
193 	} else {
194 		trtmp = X509_TRUST_get0(idx);
195 		if (trtmp == NULL) {
196 			X509err(X509_F_X509_TRUST_ADD, X509_R_INVALID_TRUST);
197 			return 0;
198 		}
199 	}
200 
201 	if ((name_dup = strdup(name)) == NULL)
202 		goto err;
203 
204 	/* free existing name if dynamic */
205 	if (trtmp->flags & X509_TRUST_DYNAMIC_NAME)
206 		free(trtmp->name);
207 	/* dup supplied name */
208 	trtmp->name = name_dup;
209 	/* Keep the dynamic flag of existing entry */
210 	trtmp->flags &= X509_TRUST_DYNAMIC;
211 	/* Set all other flags */
212 	trtmp->flags |= flags;
213 
214 	trtmp->trust = id;
215 	trtmp->check_trust = ck;
216 	trtmp->arg1 = arg1;
217 	trtmp->arg2 = arg2;
218 
219 	/* If it's a new entry, manage the dynamic table */
220 	if (idx == -1) {
221 		if (trtable == NULL &&
222 		    (trtable = sk_X509_TRUST_new(tr_cmp)) == NULL)
223 			goto err;
224 		if (sk_X509_TRUST_push(trtable, trtmp) == 0)
225 			goto err;
226 	}
227 	return 1;
228 
229 err:
230 	free(name_dup);
231 	if (idx == -1)
232 		free(trtmp);
233 	X509err(X509_F_X509_TRUST_ADD, ERR_R_MALLOC_FAILURE);
234 	return 0;
235 }
236 
237 static void
238 trtable_free(X509_TRUST *p)
239 {
240 	if (!p)
241 		return;
242 	if (p->flags & X509_TRUST_DYNAMIC) {
243 		if (p->flags & X509_TRUST_DYNAMIC_NAME)
244 			free(p->name);
245 		free(p);
246 	}
247 }
248 
249 void
250 X509_TRUST_cleanup(void)
251 {
252 	unsigned int i;
253 
254 	for (i = 0; i < X509_TRUST_COUNT; i++)
255 		trtable_free(trstandard + i);
256 	sk_X509_TRUST_pop_free(trtable, trtable_free);
257 	trtable = NULL;
258 }
259 
260 int
261 X509_TRUST_get_flags(X509_TRUST *xp)
262 {
263 	return xp->flags;
264 }
265 
266 char *
267 X509_TRUST_get0_name(X509_TRUST *xp)
268 {
269 	return xp->name;
270 }
271 
272 int
273 X509_TRUST_get_trust(X509_TRUST *xp)
274 {
275 	return xp->trust;
276 }
277 
278 static int
279 trust_1oidany(X509_TRUST *trust, X509 *x, int flags)
280 {
281 	if (x->aux && (x->aux->trust || x->aux->reject))
282 		return obj_trust(trust->arg1, x, flags);
283 	/* we don't have any trust settings: for compatibility
284 	 * we return trusted if it is self signed
285 	 */
286 	return trust_compat(trust, x, flags);
287 }
288 
289 static int
290 trust_1oid(X509_TRUST *trust, X509 *x, int flags)
291 {
292 	if (x->aux)
293 		return obj_trust(trust->arg1, x, flags);
294 	return X509_TRUST_UNTRUSTED;
295 }
296 
297 static int
298 trust_compat(X509_TRUST *trust, X509 *x, int flags)
299 {
300 	X509_check_purpose(x, -1, 0);
301 	if (x->ex_flags & EXFLAG_SS)
302 		return X509_TRUST_TRUSTED;
303 	else
304 		return X509_TRUST_UNTRUSTED;
305 }
306 
307 static int
308 obj_trust(int id, X509 *x, int flags)
309 {
310 	ASN1_OBJECT *obj;
311 	int i;
312 	X509_CERT_AUX *ax;
313 
314 	ax = x->aux;
315 	if (!ax)
316 		return X509_TRUST_UNTRUSTED;
317 	if (ax->reject) {
318 		for (i = 0; i < sk_ASN1_OBJECT_num(ax->reject); i++) {
319 			obj = sk_ASN1_OBJECT_value(ax->reject, i);
320 			if (OBJ_obj2nid(obj) == id)
321 				return X509_TRUST_REJECTED;
322 		}
323 	}
324 	if (ax->trust) {
325 		for (i = 0; i < sk_ASN1_OBJECT_num(ax->trust); i++) {
326 			obj = sk_ASN1_OBJECT_value(ax->trust, i);
327 			if (OBJ_obj2nid(obj) == id)
328 				return X509_TRUST_TRUSTED;
329 		}
330 	}
331 	return X509_TRUST_UNTRUSTED;
332 }
333