2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
5 /* ====================================================================
6 * Copyright (c) 2000-2004 The OpenSSL Project. All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
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
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/)"
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.
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.
34 * 6. Redistributions of any form whatsoever must retain the following
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
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 * ====================================================================
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).
59 #include <openssl/ocsp.h>
60 #include <openssl/err.h>
63 static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs, STACK_OF(X509) *certs,
64 X509_STORE *st, unsigned long flags);
65 static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id);
66 static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain, unsigned long flags);
67 static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, OCSP_CERTID **ret);
68 static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid, STACK_OF(OCSP_SINGLERESP) *sresp);
69 static int ocsp_check_delegated(X509 *x, int flags);
70 static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req, X509_NAME *nm, STACK_OF(X509) *certs,
71 X509_STORE *st, unsigned long flags);
73 /* Verify a basic response message */
75 int OCSP_basic_verify(OCSP_BASICRESP *bs, STACK_OF(X509) *certs,
76 X509_STORE *st, unsigned long flags)
79 STACK_OF(X509) *chain = NULL;
80 STACK_OF(X509) *tmpchain = NULL;
81 X509_STORE *tmpstore = NULL;
84 ret = ocsp_find_signer(&signer, bs, certs, st, flags);
87 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND);
90 if ((ret == 2) && (flags & OCSP_TRUSTOTHER))
92 if (!(flags & OCSP_NOSIGS))
95 skey = X509_get_pubkey(signer);
96 ret = OCSP_BASICRESP_verify(bs, skey, 0);
100 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_SIGNATURE_FAILURE);
104 if (!(flags & OCSP_NOVERIFY))
108 /* If we trust the signer, we don't need to build a chain.
109 * (If the signer is a root certificate, X509_verify_cert()
110 * would fail anyway!)
112 if (chain == certs) goto verified_chain;
114 /* If we trust some "other" certificates, allow partial
115 * chains (because some of them might be
116 * Intermediate CA Certificates), put them in a store and
117 * attempt to build a trusted chain.
119 if ((flags & OCSP_TRUSTOTHER) && (certs != NULL))
121 tmpstore = X509_STORE_new();
125 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, ERR_R_MALLOC_FAILURE);
128 for (i = 0; i < sk_X509_num(certs); i++)
130 X509 *xother = sk_X509_value(certs, i);
131 if (!X509_STORE_add_cert(tmpstore, xother))
138 init_res = X509_STORE_CTX_init(&ctx, tmpstore, signer, NULL);
142 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,ERR_R_X509_LIB);
145 X509_STORE_CTX_set_purpose(&ctx, X509_PURPOSE_OCSP_HELPER);
146 X509_STORE_CTX_set_flags(&ctx, X509_V_FLAG_PARTIAL_CHAIN);
147 ret = X509_verify_cert(&ctx);
150 chain = tmpchain = X509_STORE_CTX_get1_chain(&ctx);
151 X509_STORE_CTX_cleanup(&ctx);
154 X509_STORE_CTX_cleanup(&ctx);
157 /* Attempt to build a chain up to a Root Certificate in the
158 * trust store provided by the caller.
160 if(flags & OCSP_NOCHAIN)
161 init_res = X509_STORE_CTX_init(&ctx, st, signer, NULL);
163 init_res = X509_STORE_CTX_init(&ctx, st, signer, bs->certs);
167 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,ERR_R_X509_LIB);
171 X509_STORE_CTX_set_purpose(&ctx, X509_PURPOSE_OCSP_HELPER);
172 ret = X509_verify_cert(&ctx);
173 chain = tmpchain = X509_STORE_CTX_get1_chain(&ctx);
174 X509_STORE_CTX_cleanup(&ctx);
177 i = X509_STORE_CTX_get_error(&ctx);
178 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,OCSP_R_CERTIFICATE_VERIFY_ERROR);
179 ERR_add_error_data(2, "Verify error:",
180 X509_verify_cert_error_string(i));
185 if(flags & OCSP_NOCHECKS)
190 /* At this point we have a valid certificate chain
191 * need to verify it against the OCSP issuer criteria.
193 ret = ocsp_check_issuer(bs, chain, flags);
195 /* If fatal error or valid match then finish */
196 if (ret != 0) goto end;
198 /* Easy case: explicitly trusted. Get root CA and
199 * check for explicit trust
201 if(flags & OCSP_NOEXPLICIT) goto end;
203 x = sk_X509_value(chain, sk_X509_num(chain) - 1);
204 if(X509_check_trust(x, NID_OCSP_sign, 0) != X509_TRUST_TRUSTED)
206 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,OCSP_R_ROOT_CA_NOT_TRUSTED);
215 if(tmpchain) sk_X509_pop_free(tmpchain, X509_free);
216 if(tmpstore) X509_STORE_free(tmpstore);
221 static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs, STACK_OF(X509) *certs,
222 X509_STORE *st, unsigned long flags)
225 OCSP_RESPID *rid = bs->tbsResponseData->responderId;
226 if ((signer = ocsp_find_signer_sk(certs, rid)))
231 if(!(flags & OCSP_NOINTERN) &&
232 (signer = ocsp_find_signer_sk(bs->certs, rid)))
237 /* Maybe lookup from store if by subject name */
244 static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id)
247 unsigned char tmphash[SHA_DIGEST_LENGTH], *keyhash;
250 /* Easy if lookup by name */
251 if (id->type == V_OCSP_RESPID_NAME)
252 return X509_find_by_subject(certs, id->value.byName);
254 /* Lookup by key hash */
256 /* If key hash isn't SHA1 length then forget it */
257 if (id->value.byKey->length != SHA_DIGEST_LENGTH) return NULL;
258 keyhash = id->value.byKey->data;
259 /* Calculate hash of each key and compare */
260 for (i = 0; i < sk_X509_num(certs); i++)
262 x = sk_X509_value(certs, i);
263 X509_pubkey_digest(x, EVP_sha1(), tmphash, NULL);
264 if(!memcmp(keyhash, tmphash, SHA_DIGEST_LENGTH))
271 static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain, unsigned long flags)
273 STACK_OF(OCSP_SINGLERESP) *sresp;
275 OCSP_CERTID *caid = NULL;
277 sresp = bs->tbsResponseData->responses;
279 if (sk_X509_num(chain) <= 0)
281 OCSPerr(OCSP_F_OCSP_CHECK_ISSUER, OCSP_R_NO_CERTIFICATES_IN_CHAIN);
285 /* See if the issuer IDs match. */
286 i = ocsp_check_ids(sresp, &caid);
288 /* If ID mismatch or other error then return */
289 if (i <= 0) return i;
291 signer = sk_X509_value(chain, 0);
292 /* Check to see if OCSP responder CA matches request CA */
293 if (sk_X509_num(chain) > 1)
295 sca = sk_X509_value(chain, 1);
296 i = ocsp_match_issuerid(sca, caid, sresp);
300 /* We have a match, if extensions OK then success */
301 if (ocsp_check_delegated(signer, flags)) return 1;
306 /* Otherwise check if OCSP request signed directly by request CA */
307 return ocsp_match_issuerid(signer, caid, sresp);
311 /* Check the issuer certificate IDs for equality. If there is a mismatch with the same
312 * algorithm then there's no point trying to match any certificates against the issuer.
313 * If the issuer IDs all match then we just need to check equality against one of them.
316 static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, OCSP_CERTID **ret)
318 OCSP_CERTID *tmpid, *cid;
321 idcount = sk_OCSP_SINGLERESP_num(sresp);
324 OCSPerr(OCSP_F_OCSP_CHECK_IDS, OCSP_R_RESPONSE_CONTAINS_NO_REVOCATION_DATA);
328 cid = sk_OCSP_SINGLERESP_value(sresp, 0)->certId;
332 for (i = 1; i < idcount; i++)
334 tmpid = sk_OCSP_SINGLERESP_value(sresp, i)->certId;
335 /* Check to see if IDs match */
336 if (OCSP_id_issuer_cmp(cid, tmpid))
338 /* If algoritm mismatch let caller deal with it */
339 if (OBJ_cmp(tmpid->hashAlgorithm->algorithm,
340 cid->hashAlgorithm->algorithm))
347 /* All IDs match: only need to check one ID */
353 static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid,
354 STACK_OF(OCSP_SINGLERESP) *sresp)
356 /* If only one ID to match then do it */
362 unsigned char md[EVP_MAX_MD_SIZE];
363 if (!(dgst = EVP_get_digestbyobj(cid->hashAlgorithm->algorithm)))
365 OCSPerr(OCSP_F_OCSP_MATCH_ISSUERID, OCSP_R_UNKNOWN_MESSAGE_DIGEST);
369 mdlen = EVP_MD_size(dgst);
372 if ((cid->issuerNameHash->length != mdlen) ||
373 (cid->issuerKeyHash->length != mdlen))
375 iname = X509_get_subject_name(cert);
376 if (!X509_NAME_digest(iname, dgst, md, NULL))
378 if (memcmp(md, cid->issuerNameHash->data, mdlen))
380 X509_pubkey_digest(cert, dgst, md, NULL);
381 if (memcmp(md, cid->issuerKeyHash->data, mdlen))
389 /* We have to match the whole lot */
392 for (i = 0; i < sk_OCSP_SINGLERESP_num(sresp); i++)
394 tmpid = sk_OCSP_SINGLERESP_value(sresp, i)->certId;
395 ret = ocsp_match_issuerid(cert, tmpid, NULL);
396 if (ret <= 0) return ret;
403 static int ocsp_check_delegated(X509 *x, int flags)
405 X509_check_purpose(x, -1, 0);
406 if ((x->ex_flags & EXFLAG_XKUSAGE) &&
407 (x->ex_xkusage & XKU_OCSP_SIGN))
409 OCSPerr(OCSP_F_OCSP_CHECK_DELEGATED, OCSP_R_MISSING_OCSPSIGNING_USAGE);
413 /* Verify an OCSP request. This is fortunately much easier than OCSP
414 * response verify. Just find the signers certificate and verify it
415 * against a given trust value.
418 int OCSP_request_verify(OCSP_REQUEST *req, STACK_OF(X509) *certs, X509_STORE *store, unsigned long flags)
425 if (!req->optionalSignature)
427 OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_REQUEST_NOT_SIGNED);
430 gen = req->tbsRequest->requestorName;
431 if (!gen || gen->type != GEN_DIRNAME)
433 OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_UNSUPPORTED_REQUESTORNAME_TYPE);
436 nm = gen->d.directoryName;
437 ret = ocsp_req_find_signer(&signer, req, nm, certs, store, flags);
440 OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND);
443 if ((ret == 2) && (flags & OCSP_TRUSTOTHER))
444 flags |= OCSP_NOVERIFY;
445 if (!(flags & OCSP_NOSIGS))
448 skey = X509_get_pubkey(signer);
449 ret = OCSP_REQUEST_verify(req, skey);
453 OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_SIGNATURE_FAILURE);
457 if (!(flags & OCSP_NOVERIFY))
460 if(flags & OCSP_NOCHAIN)
461 init_res = X509_STORE_CTX_init(&ctx, store, signer, NULL);
463 init_res = X509_STORE_CTX_init(&ctx, store, signer,
464 req->optionalSignature->certs);
467 OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY,ERR_R_X509_LIB);
471 X509_STORE_CTX_set_purpose(&ctx, X509_PURPOSE_OCSP_HELPER);
472 X509_STORE_CTX_set_trust(&ctx, X509_TRUST_OCSP_REQUEST);
473 ret = X509_verify_cert(&ctx);
474 X509_STORE_CTX_cleanup(&ctx);
477 ret = X509_STORE_CTX_get_error(&ctx);
478 OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY,OCSP_R_CERTIFICATE_VERIFY_ERROR);
479 ERR_add_error_data(2, "Verify error:",
480 X509_verify_cert_error_string(ret));
487 static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req, X509_NAME *nm, STACK_OF(X509) *certs,
488 X509_STORE *st, unsigned long flags)
491 if(!(flags & OCSP_NOINTERN))
493 signer = X509_find_by_subject(req->optionalSignature->certs, nm);
498 signer = X509_find_by_subject(certs, nm);