xref: /openbsd/lib/libcrypto/ocsp/ocsp_cl.c (revision a6445c1d)
1 /* $OpenBSD: ocsp_cl.c,v 1.8 2014/10/18 17:20:40 jsing Exp $ */
2 /* Written by Tom Titchener <Tom_Titchener@groove.net> for the OpenSSL
3  * project. */
4 
5 /* History:
6    This file was transfered to Richard Levitte from CertCo by Kathy
7    Weinhold in mid-spring 2000 to be included in OpenSSL or released
8    as a patch kit. */
9 
10 /* ====================================================================
11  * Copyright (c) 1998-2000 The OpenSSL Project.  All rights reserved.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  *
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  *
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in
22  *    the documentation and/or other materials provided with the
23  *    distribution.
24  *
25  * 3. All advertising materials mentioning features or use of this
26  *    software must display the following acknowledgment:
27  *    "This product includes software developed by the OpenSSL Project
28  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
29  *
30  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
31  *    endorse or promote products derived from this software without
32  *    prior written permission. For written permission, please contact
33  *    openssl-core@openssl.org.
34  *
35  * 5. Products derived from this software may not be called "OpenSSL"
36  *    nor may "OpenSSL" appear in their names without prior written
37  *    permission of the OpenSSL Project.
38  *
39  * 6. Redistributions of any form whatsoever must retain the following
40  *    acknowledgment:
41  *    "This product includes software developed by the OpenSSL Project
42  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
43  *
44  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
45  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
47  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
48  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
49  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
50  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
51  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
53  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
54  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
55  * OF THE POSSIBILITY OF SUCH DAMAGE.
56  * ====================================================================
57  *
58  * This product includes cryptographic software written by Eric Young
59  * (eay@cryptsoft.com).  This product includes software written by Tim
60  * Hudson (tjh@cryptsoft.com).
61  *
62  */
63 
64 #include <stdio.h>
65 #include <time.h>
66 
67 #include <openssl/err.h>
68 #include <openssl/ocsp.h>
69 #include <openssl/objects.h>
70 #include <openssl/pem.h>
71 #include <openssl/x509.h>
72 #include <openssl/x509v3.h>
73 
74 /* Utility functions related to sending OCSP requests and extracting
75  * relevant information from the response.
76  */
77 
78 /* Add an OCSP_CERTID to an OCSP request. Return new OCSP_ONEREQ
79  * pointer: useful if we want to add extensions.
80  */
81 OCSP_ONEREQ *
82 OCSP_request_add0_id(OCSP_REQUEST *req, OCSP_CERTID *cid)
83 {
84 	OCSP_ONEREQ *one = NULL;
85 
86 	if (!(one = OCSP_ONEREQ_new()))
87 		goto err;
88 	if (one->reqCert)
89 		OCSP_CERTID_free(one->reqCert);
90 	one->reqCert = cid;
91 	if (req && !sk_OCSP_ONEREQ_push(req->tbsRequest->requestList, one))
92 		goto err;
93 	return one;
94 
95 err:
96 	OCSP_ONEREQ_free(one);
97 	return NULL;
98 }
99 
100 /* Set requestorName from an X509_NAME structure */
101 int
102 OCSP_request_set1_name(OCSP_REQUEST *req, X509_NAME *nm)
103 {
104 	GENERAL_NAME *gen;
105 
106 	gen = GENERAL_NAME_new();
107 	if (gen == NULL)
108 		return 0;
109 	if (!X509_NAME_set(&gen->d.directoryName, nm)) {
110 		GENERAL_NAME_free(gen);
111 		return 0;
112 	}
113 	gen->type = GEN_DIRNAME;
114 	if (req->tbsRequest->requestorName)
115 		GENERAL_NAME_free(req->tbsRequest->requestorName);
116 	req->tbsRequest->requestorName = gen;
117 	return 1;
118 }
119 
120 /* Add a certificate to an OCSP request */
121 int
122 OCSP_request_add1_cert(OCSP_REQUEST *req, X509 *cert)
123 {
124 	OCSP_SIGNATURE *sig;
125 
126 	if (!req->optionalSignature)
127 		req->optionalSignature = OCSP_SIGNATURE_new();
128 	sig = req->optionalSignature;
129 	if (!sig)
130 		return 0;
131 	if (!cert)
132 		return 1;
133 	if (!sig->certs && !(sig->certs = sk_X509_new_null()))
134 		return 0;
135 
136 	if (!sk_X509_push(sig->certs, cert))
137 		return 0;
138 	CRYPTO_add(&cert->references, 1, CRYPTO_LOCK_X509);
139 	return 1;
140 }
141 
142 /* Sign an OCSP request set the requestorName to the subjec
143  * name of an optional signers certificate and include one
144  * or more optional certificates in the request. Behaves
145  * like PKCS7_sign().
146  */
147 int
148 OCSP_request_sign(OCSP_REQUEST *req, X509 *signer, EVP_PKEY *key,
149     const EVP_MD *dgst, STACK_OF(X509) *certs, unsigned long flags)
150 {
151 	int i;
152 	OCSP_SIGNATURE *sig;
153 	X509 *x;
154 
155 	if (!OCSP_request_set1_name(req, X509_get_subject_name(signer)))
156 		goto err;
157 
158 	if (!(req->optionalSignature = sig = OCSP_SIGNATURE_new()))
159 		goto err;
160 	if (key) {
161 		if (!X509_check_private_key(signer, key)) {
162 			OCSPerr(OCSP_F_OCSP_REQUEST_SIGN,
163 			    OCSP_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
164 			goto err;
165 		}
166 		if (!OCSP_REQUEST_sign(req, key, dgst))
167 			goto err;
168 	}
169 
170 	if (!(flags & OCSP_NOCERTS)) {
171 		if (!OCSP_request_add1_cert(req, signer))
172 			goto err;
173 		for (i = 0; i < sk_X509_num(certs); i++) {
174 			x = sk_X509_value(certs, i);
175 			if (!OCSP_request_add1_cert(req, x))
176 				goto err;
177 		}
178 	}
179 
180 	return 1;
181 
182 err:
183 	OCSP_SIGNATURE_free(req->optionalSignature);
184 	req->optionalSignature = NULL;
185 	return 0;
186 }
187 
188 /* Get response status */
189 int
190 OCSP_response_status(OCSP_RESPONSE *resp)
191 {
192 	return ASN1_ENUMERATED_get(resp->responseStatus);
193 }
194 
195 /* Extract basic response from OCSP_RESPONSE or NULL if
196  * no basic response present.
197  */
198 OCSP_BASICRESP *
199 OCSP_response_get1_basic(OCSP_RESPONSE *resp)
200 {
201 	OCSP_RESPBYTES *rb;
202 
203 	rb = resp->responseBytes;
204 	if (!rb) {
205 		OCSPerr(OCSP_F_OCSP_RESPONSE_GET1_BASIC,
206 		    OCSP_R_NO_RESPONSE_DATA);
207 		return NULL;
208 	}
209 	if (OBJ_obj2nid(rb->responseType) != NID_id_pkix_OCSP_basic) {
210 		OCSPerr(OCSP_F_OCSP_RESPONSE_GET1_BASIC,
211 		    OCSP_R_NOT_BASIC_RESPONSE);
212 		return NULL;
213 	}
214 
215 	return ASN1_item_unpack(rb->response, ASN1_ITEM_rptr(OCSP_BASICRESP));
216 }
217 
218 /* Return number of OCSP_SINGLERESP reponses present in
219  * a basic response.
220  */
221 int
222 OCSP_resp_count(OCSP_BASICRESP *bs)
223 {
224 	if (!bs)
225 		return -1;
226 	return sk_OCSP_SINGLERESP_num(bs->tbsResponseData->responses);
227 }
228 
229 /* Extract an OCSP_SINGLERESP response with a given index */
230 OCSP_SINGLERESP *
231 OCSP_resp_get0(OCSP_BASICRESP *bs, int idx)
232 {
233 	if (!bs)
234 		return NULL;
235 	return sk_OCSP_SINGLERESP_value(bs->tbsResponseData->responses, idx);
236 }
237 
238 /* Look single response matching a given certificate ID */
239 int
240 OCSP_resp_find(OCSP_BASICRESP *bs, OCSP_CERTID *id, int last)
241 {
242 	int i;
243 	STACK_OF(OCSP_SINGLERESP) *sresp;
244 	OCSP_SINGLERESP *single;
245 
246 	if (!bs)
247 		return -1;
248 	if (last < 0)
249 		last = 0;
250 	else
251 		last++;
252 	sresp = bs->tbsResponseData->responses;
253 	for (i = last; i < sk_OCSP_SINGLERESP_num(sresp); i++) {
254 		single = sk_OCSP_SINGLERESP_value(sresp, i);
255 		if (!OCSP_id_cmp(id, single->certId))
256 			return i;
257 	}
258 	return -1;
259 }
260 
261 /* Extract status information from an OCSP_SINGLERESP structure.
262  * Note: the revtime and reason values are only set if the
263  * certificate status is revoked. Returns numerical value of
264  * status.
265  */
266 int
267 OCSP_single_get0_status(OCSP_SINGLERESP *single, int *reason,
268     ASN1_GENERALIZEDTIME **revtime, ASN1_GENERALIZEDTIME **thisupd,
269     ASN1_GENERALIZEDTIME **nextupd)
270 {
271 	int ret;
272 	OCSP_CERTSTATUS *cst;
273 
274 	if (!single)
275 		return -1;
276 	cst = single->certStatus;
277 	ret = cst->type;
278 	if (ret == V_OCSP_CERTSTATUS_REVOKED) {
279 		OCSP_REVOKEDINFO *rev = cst->value.revoked;
280 
281 		if (revtime)
282 			*revtime = rev->revocationTime;
283 		if (reason) {
284 			if (rev->revocationReason)
285 				*reason = ASN1_ENUMERATED_get(
286 				    rev->revocationReason);
287 			else
288 				*reason = -1;
289 		}
290 	}
291 	if (thisupd)
292 		*thisupd = single->thisUpdate;
293 	if (nextupd)
294 		*nextupd = single->nextUpdate;
295 	return ret;
296 }
297 
298 /* This function combines the previous ones: look up a certificate ID and
299  * if found extract status information. Return 0 is successful.
300  */
301 int
302 OCSP_resp_find_status(OCSP_BASICRESP *bs, OCSP_CERTID *id, int *status,
303     int *reason, ASN1_GENERALIZEDTIME **revtime, ASN1_GENERALIZEDTIME **thisupd,
304     ASN1_GENERALIZEDTIME **nextupd)
305 {
306 	int i;
307 	OCSP_SINGLERESP *single;
308 
309 	i = OCSP_resp_find(bs, id, -1);
310 	/* Maybe check for multiple responses and give an error? */
311 	if (i < 0)
312 		return 0;
313 	single = OCSP_resp_get0(bs, i);
314 	i = OCSP_single_get0_status(single, reason, revtime, thisupd, nextupd);
315 	if (status)
316 		*status = i;
317 	return 1;
318 }
319 
320 /* Check validity of thisUpdate and nextUpdate fields. It is possible that the request will
321  * take a few seconds to process and/or the time wont be totally accurate. Therefore to avoid
322  * rejecting otherwise valid time we allow the times to be within 'nsec' of the current time.
323  * Also to avoid accepting very old responses without a nextUpdate field an optional maxage
324  * parameter specifies the maximum age the thisUpdate field can be.
325  */
326 int
327 OCSP_check_validity(ASN1_GENERALIZEDTIME *thisupd,
328     ASN1_GENERALIZEDTIME *nextupd, long nsec, long maxsec)
329 {
330 	int ret = 1;
331 	time_t t_now, t_tmp;
332 
333 	time(&t_now);
334 	/* Check thisUpdate is valid and not more than nsec in the future */
335 	if (!ASN1_GENERALIZEDTIME_check(thisupd)) {
336 		OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY,
337 		    OCSP_R_ERROR_IN_THISUPDATE_FIELD);
338 		ret = 0;
339 	} else {
340 		t_tmp = t_now + nsec;
341 		if (X509_cmp_time(thisupd, &t_tmp) > 0) {
342 			OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY,
343 			    OCSP_R_STATUS_NOT_YET_VALID);
344 			ret = 0;
345 		}
346 
347 		/* If maxsec specified check thisUpdate is not more than maxsec in the past */
348 		if (maxsec >= 0) {
349 			t_tmp = t_now - maxsec;
350 			if (X509_cmp_time(thisupd, &t_tmp) < 0) {
351 				OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY,
352 				    OCSP_R_STATUS_TOO_OLD);
353 				ret = 0;
354 			}
355 		}
356 	}
357 
358 	if (!nextupd)
359 		return ret;
360 
361 	/* Check nextUpdate is valid and not more than nsec in the past */
362 	if (!ASN1_GENERALIZEDTIME_check(nextupd)) {
363 		OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY,
364 		    OCSP_R_ERROR_IN_NEXTUPDATE_FIELD);
365 		ret = 0;
366 	} else {
367 		t_tmp = t_now - nsec;
368 		if (X509_cmp_time(nextupd, &t_tmp) < 0) {
369 			OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY,
370 			    OCSP_R_STATUS_EXPIRED);
371 			ret = 0;
372 		}
373 	}
374 
375 	/* Also don't allow nextUpdate to precede thisUpdate */
376 	if (ASN1_STRING_cmp(nextupd, thisupd) < 0) {
377 		OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY,
378 		    OCSP_R_NEXTUPDATE_BEFORE_THISUPDATE);
379 		ret = 0;
380 	}
381 
382 	return ret;
383 }
384