2 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
5 /* ====================================================================
6 * Copyright (c) 2000 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>
62 static X509 *ocsp_find_signer(OCSP_BASICRESP *bs, STACK_OF(X509) *certs,
63 X509_STORE *st, unsigned long flags);
64 static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id);
65 static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain, unsigned long flags);
66 static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, OCSP_CERTID **ret);
67 static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid, STACK_OF(OCSP_SINGLERESP) *sresp);
68 static int ocsp_check_delegated(X509 *x, int flags);
70 /* Verify a basic response message */
72 int OCSP_basic_verify(OCSP_BASICRESP *bs, STACK_OF(X509) *certs,
73 X509_STORE *st, unsigned long flags)
76 STACK_OF(X509) *chain = NULL;
79 signer = ocsp_find_signer(bs, certs, st, flags);
82 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND);
85 if (!(flags & OCSP_NOSIGS))
88 skey = X509_get_pubkey(signer);
89 ret = OCSP_BASICRESP_verify(bs, skey, 0);
93 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_SIGNATURE_FAILURE);
97 if (!(flags & OCSP_NOVERIFY))
99 if(flags & OCSP_NOCHAIN)
100 X509_STORE_CTX_init(&ctx, st, signer, NULL);
102 X509_STORE_CTX_init(&ctx, st, signer, bs->certs);
104 X509_STORE_CTX_set_purpose(&ctx, X509_PURPOSE_OCSP_HELPER);
105 ret = X509_verify_cert(&ctx);
106 chain = X509_STORE_CTX_get1_chain(&ctx);
107 X509_STORE_CTX_cleanup(&ctx);
110 i = X509_STORE_CTX_get_error(&ctx);
111 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,OCSP_R_CERTIFICATE_VERIFY_ERROR);
112 ERR_add_error_data(2, "Verify error:",
113 X509_verify_cert_error_string(i));
116 if(flags & OCSP_NOCHECKS)
121 /* At this point we have a valid certificate chain
122 * need to verify it against the OCSP issuer criteria.
124 ret = ocsp_check_issuer(bs, chain, flags);
126 /* If fatal error or valid match then finish */
127 if (ret != 0) goto end;
129 /* Easy case: explicitly trusted. Get root CA and
130 * check for explicit trust
132 if(flags & OCSP_NOEXPLICIT) goto end;
134 x = sk_X509_value(chain, sk_X509_num(chain) - 1);
135 if(X509_check_trust(x, NID_OCSP_sign, 0) != X509_TRUST_TRUSTED)
137 OCSPerr(OCSP_F_OCSP_BASIC_VERIFY,OCSP_R_ROOT_CA_NOT_TRUSTED);
146 if(chain) sk_X509_pop_free(chain, X509_free);
151 static X509 *ocsp_find_signer(OCSP_BASICRESP *bs, STACK_OF(X509) *certs,
152 X509_STORE *st, unsigned long flags)
155 OCSP_RESPID *rid = bs->tbsResponseData->responderId;
156 if ((signer = ocsp_find_signer_sk(certs, rid)))
158 if(!(flags & OCSP_NOINTERN) &&
159 (signer = ocsp_find_signer_sk(bs->certs, rid)))
161 /* Maybe lookup from store if by subject name */
167 static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id)
170 unsigned char tmphash[SHA_DIGEST_LENGTH], *keyhash;
171 ASN1_BIT_STRING *key;
175 /* Easy if lookup by name */
176 if (id->type == V_OCSP_RESPID_NAME)
177 return X509_find_by_subject(certs, id->value.byName);
179 /* Lookup by key hash */
181 /* If key hash isn't SHA1 length then forget it */
182 if (id->value.byKey->length != SHA_DIGEST_LENGTH) return NULL;
183 keyhash = id->value.byKey->data;
184 /* Calculate hash of each key and compare */
185 for (i = 0; i < sk_X509_num(certs); i++)
187 x = sk_X509_value(certs, i);
188 key = x->cert_info->key->public_key;
189 EVP_DigestInit(&ctx,EVP_sha1());
190 EVP_DigestUpdate(&ctx,key->data, key->length);
191 EVP_DigestFinal(&ctx,tmphash,NULL);
192 if(!memcmp(keyhash, tmphash, SHA_DIGEST_LENGTH))
199 static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain, unsigned long flags)
201 STACK_OF(OCSP_SINGLERESP) *sresp;
203 OCSP_CERTID *caid = NULL;
205 sresp = bs->tbsResponseData->responses;
207 if (sk_X509_num(chain) <= 0)
209 OCSPerr(OCSP_F_OCSP_CHECK_ISSUER, OCSP_R_NO_CERTIFICATES_IN_CHAIN);
213 /* See if the issuer IDs match. */
214 i = ocsp_check_ids(sresp, &caid);
216 /* If ID mismatch or other error then return */
217 if (i <= 0) return i;
219 signer = sk_X509_value(chain, 0);
220 /* Check to see if OCSP responder CA matches request CA */
221 if (sk_X509_num(chain) > 1)
223 sca = sk_X509_value(chain, 1);
224 i = ocsp_match_issuerid(sca, caid, sresp);
228 /* We have a match, if extensions OK then success */
229 if (ocsp_check_delegated(signer, flags)) return 1;
234 /* Otherwise check if OCSP request signed directly by request CA */
235 return ocsp_match_issuerid(signer, caid, sresp);
239 /* Check the issuer certificate IDs for equality. If there is a mismatch with the same
240 * algorithm then there's no point trying to match any certificates against the issuer.
241 * If the issuer IDs all match then we just need to check equality against one of them.
244 static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, OCSP_CERTID **ret)
246 OCSP_CERTID *tmpid, *cid;
249 idcount = sk_OCSP_SINGLERESP_num(sresp);
252 OCSPerr(OCSP_F_OCSP_CHECK_IDS, OCSP_R_RESPONSE_CONTAINS_NO_REVOCATION_DATA);
256 cid = sk_OCSP_SINGLERESP_value(sresp, 0)->certId;
260 for (i = 1; i < idcount; i++)
262 tmpid = sk_OCSP_SINGLERESP_value(sresp, 0)->certId;
263 /* Check to see if IDs match */
264 if (OCSP_id_issuer_cmp(cid, tmpid))
266 /* If algoritm mismatch let caller deal with it */
267 if (OBJ_cmp(tmpid->hashAlgorithm->algorithm,
268 cid->hashAlgorithm->algorithm))
275 /* All IDs match: only need to check one ID */
281 static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid,
282 STACK_OF(OCSP_SINGLERESP) *sresp)
284 /* If only one ID to match then do it */
290 ASN1_BIT_STRING *ikey;
292 unsigned char md[EVP_MAX_MD_SIZE];
293 if (!(dgst = EVP_get_digestbyobj(cid->hashAlgorithm->algorithm)))
295 OCSPerr(OCSP_F_OCSP_MATCH_ISSUERID, OCSP_R_UNKNOWN_MESSAGE_DIGEST);
299 mdlen = EVP_MD_size(dgst);
300 if ((cid->issuerNameHash->length != mdlen) ||
301 (cid->issuerKeyHash->length != mdlen))
303 iname = X509_get_issuer_name(cert);
304 if (!X509_NAME_digest(iname, dgst, md, NULL))
306 if (memcmp(md, cid->issuerNameHash->data, mdlen))
308 ikey = cert->cert_info->key->public_key;
310 EVP_DigestInit(&ctx,dgst);
311 EVP_DigestUpdate(&ctx,ikey->data, ikey->length);
312 EVP_DigestFinal(&ctx,md,NULL);
313 if (memcmp(md, cid->issuerKeyHash->data, mdlen))
321 /* We have to match the whole lot */
324 for (i = 0; i < sk_OCSP_SINGLERESP_num(sresp); i++)
326 tmpid = sk_OCSP_SINGLERESP_value(sresp, 0)->certId;
327 ret = ocsp_match_issuerid(cert, tmpid, NULL);
328 if (ret <= 0) return ret;
335 static int ocsp_check_delegated(X509 *x, int flags)
337 X509_check_purpose(x, -1, 0);
338 if ((x->ex_flags & EXFLAG_XKUSAGE) &&
339 (x->ex_xkusage & XKU_OCSP_SIGN))
341 OCSPerr(OCSP_F_OCSP_CHECK_DELEGATED, OCSP_R_MISSING_OCSPSIGNING_USAGE);