| 1 |
/* ocsp_vfy.c */ |
| 2 |
/* |
| 3 |
* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project |
| 4 |
* 2000. |
| 5 |
*/ |
| 6 |
/* ==================================================================== |
| 7 |
* Copyright (c) 2000-2004 The OpenSSL Project. All rights reserved. |
| 8 |
* |
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* Redistribution and use in source and binary forms, with or without |
| 10 |
* modification, are permitted provided that the following conditions |
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* are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
| 14 |
* notice, this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
| 17 |
* notice, this list of conditions and the following disclaimer in |
| 18 |
* the documentation and/or other materials provided with the |
| 19 |
* distribution. |
| 20 |
* |
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* 3. All advertising materials mentioning features or use of this |
| 22 |
* software must display the following acknowledgment: |
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* "This product includes software developed by the OpenSSL Project |
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* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" |
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* |
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* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to |
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* endorse or promote products derived from this software without |
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* prior written permission. For written permission, please contact |
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* licensing@OpenSSL.org. |
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* |
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* 5. Products derived from this software may not be called "OpenSSL" |
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* nor may "OpenSSL" appear in their names without prior written |
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* permission of the OpenSSL Project. |
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* |
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* 6. Redistributions of any form whatsoever must retain the following |
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* acknowledgment: |
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* "This product includes software developed by the OpenSSL Project |
| 38 |
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" |
| 39 |
* |
| 40 |
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY |
| 41 |
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 42 |
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 43 |
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR |
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* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
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* OF THE POSSIBILITY OF SUCH DAMAGE. |
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* ==================================================================== |
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* |
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* This product includes cryptographic software written by Eric Young |
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* (eay@cryptsoft.com). This product includes software written by Tim |
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* Hudson (tjh@cryptsoft.com). |
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* |
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*/ |
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|
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#include <openssl/ocsp.h> |
| 61 |
#include <openssl/err.h> |
| 62 |
#include <string.h> |
| 63 |
|
| 64 |
static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs, |
| 65 |
STACK_OF(X509) *certs, X509_STORE *st, |
| 66 |
unsigned long flags); |
| 67 |
static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id); |
| 68 |
static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain, |
| 69 |
unsigned long flags); |
| 70 |
static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, |
| 71 |
OCSP_CERTID **ret); |
| 72 |
static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid, |
| 73 |
STACK_OF(OCSP_SINGLERESP) *sresp); |
| 74 |
static int ocsp_check_delegated(X509 *x, int flags); |
| 75 |
static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req, |
| 76 |
X509_NAME *nm, STACK_OF(X509) *certs, |
| 77 |
X509_STORE *st, unsigned long flags); |
| 78 |
|
| 79 |
/* Verify a basic response message */ |
| 80 |
|
| 81 |
int OCSP_basic_verify(OCSP_BASICRESP *bs, STACK_OF(X509) *certs, |
| 82 |
X509_STORE *st, unsigned long flags) |
| 83 |
{ |
| 84 |
X509 *signer, *x; |
| 85 |
STACK_OF(X509) *chain = NULL; |
| 86 |
STACK_OF(X509) *untrusted = NULL; |
| 87 |
X509_STORE_CTX ctx; |
| 88 |
int i, ret = 0; |
| 89 |
ret = ocsp_find_signer(&signer, bs, certs, st, flags); |
| 90 |
if (!ret) { |
| 91 |
OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, |
| 92 |
OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND); |
| 93 |
goto end; |
| 94 |
} |
| 95 |
if ((ret == 2) && (flags & OCSP_TRUSTOTHER)) |
| 96 |
flags |= OCSP_NOVERIFY; |
| 97 |
if (!(flags & OCSP_NOSIGS)) { |
| 98 |
EVP_PKEY *skey; |
| 99 |
skey = X509_get_pubkey(signer); |
| 100 |
if (skey) { |
| 101 |
ret = OCSP_BASICRESP_verify(bs, skey, 0); |
| 102 |
EVP_PKEY_free(skey); |
| 103 |
} |
| 104 |
if (!skey || ret <= 0) { |
| 105 |
OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_SIGNATURE_FAILURE); |
| 106 |
goto end; |
| 107 |
} |
| 108 |
} |
| 109 |
if (!(flags & OCSP_NOVERIFY)) { |
| 110 |
int init_res; |
| 111 |
if (flags & OCSP_NOCHAIN) { |
| 112 |
untrusted = NULL; |
| 113 |
} else if (bs->certs && certs) { |
| 114 |
untrusted = sk_X509_dup(bs->certs); |
| 115 |
for (i = 0; i < sk_X509_num(certs); i++) { |
| 116 |
if (!sk_X509_push(untrusted, sk_X509_value(certs, i))) { |
| 117 |
OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, ERR_R_MALLOC_FAILURE); |
| 118 |
goto end; |
| 119 |
} |
| 120 |
} |
| 121 |
} else { |
| 122 |
untrusted = bs->certs; |
| 123 |
} |
| 124 |
init_res = X509_STORE_CTX_init(&ctx, st, signer, untrusted); |
| 125 |
if (!init_res) { |
| 126 |
ret = -1; |
| 127 |
OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, ERR_R_X509_LIB); |
| 128 |
goto end; |
| 129 |
} |
| 130 |
|
| 131 |
X509_STORE_CTX_set_purpose(&ctx, X509_PURPOSE_OCSP_HELPER); |
| 132 |
ret = X509_verify_cert(&ctx); |
| 133 |
chain = X509_STORE_CTX_get1_chain(&ctx); |
| 134 |
X509_STORE_CTX_cleanup(&ctx); |
| 135 |
if (ret <= 0) { |
| 136 |
i = X509_STORE_CTX_get_error(&ctx); |
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OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, |
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OCSP_R_CERTIFICATE_VERIFY_ERROR); |
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ERR_add_error_data(2, "Verify error:", |
| 140 |
X509_verify_cert_error_string(i)); |
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goto end; |
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} |
| 143 |
if (flags & OCSP_NOCHECKS) { |
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ret = 1; |
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goto end; |
| 146 |
} |
| 147 |
/* |
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* At this point we have a valid certificate chain need to verify it |
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* against the OCSP issuer criteria. |
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*/ |
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ret = ocsp_check_issuer(bs, chain, flags); |
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|
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/* If fatal error or valid match then finish */ |
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if (ret != 0) |
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goto end; |
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|
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/* |
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* Easy case: explicitly trusted. Get root CA and check for explicit |
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* trust |
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*/ |
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if (flags & OCSP_NOEXPLICIT) |
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goto end; |
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|
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x = sk_X509_value(chain, sk_X509_num(chain) - 1); |
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if (X509_check_trust(x, NID_OCSP_sign, 0) != X509_TRUST_TRUSTED) { |
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OCSPerr(OCSP_F_OCSP_BASIC_VERIFY, OCSP_R_ROOT_CA_NOT_TRUSTED); |
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goto end; |
| 168 |
} |
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ret = 1; |
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} |
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|
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end: |
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if (chain) |
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sk_X509_pop_free(chain, X509_free); |
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if (bs->certs && certs) |
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sk_X509_free(untrusted); |
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return ret; |
| 178 |
} |
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|
| 180 |
static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs, |
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STACK_OF(X509) *certs, X509_STORE *st, |
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unsigned long flags) |
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{ |
| 184 |
X509 *signer; |
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OCSP_RESPID *rid = bs->tbsResponseData->responderId; |
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if ((signer = ocsp_find_signer_sk(certs, rid))) { |
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*psigner = signer; |
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return 2; |
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} |
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if (!(flags & OCSP_NOINTERN) && |
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(signer = ocsp_find_signer_sk(bs->certs, rid))) { |
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*psigner = signer; |
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return 1; |
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} |
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/* Maybe lookup from store if by subject name */ |
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|
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*psigner = NULL; |
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return 0; |
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} |
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|
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static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id) |
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{ |
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int i; |
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unsigned char tmphash[SHA_DIGEST_LENGTH], *keyhash; |
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X509 *x; |
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|
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/* Easy if lookup by name */ |
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if (id->type == V_OCSP_RESPID_NAME) |
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return X509_find_by_subject(certs, id->value.byName); |
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|
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/* Lookup by key hash */ |
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|
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/* If key hash isn't SHA1 length then forget it */ |
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if (id->value.byKey->length != SHA_DIGEST_LENGTH) |
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return NULL; |
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keyhash = id->value.byKey->data; |
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/* Calculate hash of each key and compare */ |
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for (i = 0; i < sk_X509_num(certs); i++) { |
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x = sk_X509_value(certs, i); |
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X509_pubkey_digest(x, EVP_sha1(), tmphash, NULL); |
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if (!memcmp(keyhash, tmphash, SHA_DIGEST_LENGTH)) |
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return x; |
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} |
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return NULL; |
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} |
| 226 |
|
| 227 |
static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain, |
| 228 |
unsigned long flags) |
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{ |
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STACK_OF(OCSP_SINGLERESP) *sresp; |
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X509 *signer, *sca; |
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OCSP_CERTID *caid = NULL; |
| 233 |
int i; |
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sresp = bs->tbsResponseData->responses; |
| 235 |
|
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if (sk_X509_num(chain) <= 0) { |
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OCSPerr(OCSP_F_OCSP_CHECK_ISSUER, OCSP_R_NO_CERTIFICATES_IN_CHAIN); |
| 238 |
return -1; |
| 239 |
} |
| 240 |
|
| 241 |
/* See if the issuer IDs match. */ |
| 242 |
i = ocsp_check_ids(sresp, &caid); |
| 243 |
|
| 244 |
/* If ID mismatch or other error then return */ |
| 245 |
if (i <= 0) |
| 246 |
return i; |
| 247 |
|
| 248 |
signer = sk_X509_value(chain, 0); |
| 249 |
/* Check to see if OCSP responder CA matches request CA */ |
| 250 |
if (sk_X509_num(chain) > 1) { |
| 251 |
sca = sk_X509_value(chain, 1); |
| 252 |
i = ocsp_match_issuerid(sca, caid, sresp); |
| 253 |
if (i < 0) |
| 254 |
return i; |
| 255 |
if (i) { |
| 256 |
/* We have a match, if extensions OK then success */ |
| 257 |
if (ocsp_check_delegated(signer, flags)) |
| 258 |
return 1; |
| 259 |
return 0; |
| 260 |
} |
| 261 |
} |
| 262 |
|
| 263 |
/* Otherwise check if OCSP request signed directly by request CA */ |
| 264 |
return ocsp_match_issuerid(signer, caid, sresp); |
| 265 |
} |
| 266 |
|
| 267 |
/* |
| 268 |
* Check the issuer certificate IDs for equality. If there is a mismatch with |
| 269 |
* the same algorithm then there's no point trying to match any certificates |
| 270 |
* against the issuer. If the issuer IDs all match then we just need to check |
| 271 |
* equality against one of them. |
| 272 |
*/ |
| 273 |
|
| 274 |
static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, OCSP_CERTID **ret) |
| 275 |
{ |
| 276 |
OCSP_CERTID *tmpid, *cid; |
| 277 |
int i, idcount; |
| 278 |
|
| 279 |
idcount = sk_OCSP_SINGLERESP_num(sresp); |
| 280 |
if (idcount <= 0) { |
| 281 |
OCSPerr(OCSP_F_OCSP_CHECK_IDS, |
| 282 |
OCSP_R_RESPONSE_CONTAINS_NO_REVOCATION_DATA); |
| 283 |
return -1; |
| 284 |
} |
| 285 |
|
| 286 |
cid = sk_OCSP_SINGLERESP_value(sresp, 0)->certId; |
| 287 |
|
| 288 |
*ret = NULL; |
| 289 |
|
| 290 |
for (i = 1; i < idcount; i++) { |
| 291 |
tmpid = sk_OCSP_SINGLERESP_value(sresp, i)->certId; |
| 292 |
/* Check to see if IDs match */ |
| 293 |
if (OCSP_id_issuer_cmp(cid, tmpid)) { |
| 294 |
/* If algoritm mismatch let caller deal with it */ |
| 295 |
if (OBJ_cmp(tmpid->hashAlgorithm->algorithm, |
| 296 |
cid->hashAlgorithm->algorithm)) |
| 297 |
return 2; |
| 298 |
/* Else mismatch */ |
| 299 |
return 0; |
| 300 |
} |
| 301 |
} |
| 302 |
|
| 303 |
/* All IDs match: only need to check one ID */ |
| 304 |
*ret = cid; |
| 305 |
return 1; |
| 306 |
} |
| 307 |
|
| 308 |
static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid, |
| 309 |
STACK_OF(OCSP_SINGLERESP) *sresp) |
| 310 |
{ |
| 311 |
/* If only one ID to match then do it */ |
| 312 |
if (cid) { |
| 313 |
const EVP_MD *dgst; |
| 314 |
X509_NAME *iname; |
| 315 |
int mdlen; |
| 316 |
unsigned char md[EVP_MAX_MD_SIZE]; |
| 317 |
if (!(dgst = EVP_get_digestbyobj(cid->hashAlgorithm->algorithm))) { |
| 318 |
OCSPerr(OCSP_F_OCSP_MATCH_ISSUERID, |
| 319 |
OCSP_R_UNKNOWN_MESSAGE_DIGEST); |
| 320 |
return -1; |
| 321 |
} |
| 322 |
|
| 323 |
mdlen = EVP_MD_size(dgst); |
| 324 |
if ((cid->issuerNameHash->length != mdlen) || |
| 325 |
(cid->issuerKeyHash->length != mdlen)) |
| 326 |
return 0; |
| 327 |
iname = X509_get_subject_name(cert); |
| 328 |
if (!X509_NAME_digest(iname, dgst, md, NULL)) |
| 329 |
return -1; |
| 330 |
if (memcmp(md, cid->issuerNameHash->data, mdlen)) |
| 331 |
return 0; |
| 332 |
X509_pubkey_digest(cert, EVP_sha1(), md, NULL); |
| 333 |
if (memcmp(md, cid->issuerKeyHash->data, mdlen)) |
| 334 |
return 0; |
| 335 |
|
| 336 |
return 1; |
| 337 |
|
| 338 |
} else { |
| 339 |
/* We have to match the whole lot */ |
| 340 |
int i, ret; |
| 341 |
OCSP_CERTID *tmpid; |
| 342 |
for (i = 0; i < sk_OCSP_SINGLERESP_num(sresp); i++) { |
| 343 |
tmpid = sk_OCSP_SINGLERESP_value(sresp, i)->certId; |
| 344 |
ret = ocsp_match_issuerid(cert, tmpid, NULL); |
| 345 |
if (ret <= 0) |
| 346 |
return ret; |
| 347 |
} |
| 348 |
return 1; |
| 349 |
} |
| 350 |
|
| 351 |
} |
| 352 |
|
| 353 |
static int ocsp_check_delegated(X509 *x, int flags) |
| 354 |
{ |
| 355 |
X509_check_purpose(x, -1, 0); |
| 356 |
if ((x->ex_flags & EXFLAG_XKUSAGE) && (x->ex_xkusage & XKU_OCSP_SIGN)) |
| 357 |
return 1; |
| 358 |
OCSPerr(OCSP_F_OCSP_CHECK_DELEGATED, OCSP_R_MISSING_OCSPSIGNING_USAGE); |
| 359 |
return 0; |
| 360 |
} |
| 361 |
|
| 362 |
/* |
| 363 |
* Verify an OCSP request. This is fortunately much easier than OCSP response |
| 364 |
* verify. Just find the signers certificate and verify it against a given |
| 365 |
* trust value. |
| 366 |
*/ |
| 367 |
|
| 368 |
int OCSP_request_verify(OCSP_REQUEST *req, STACK_OF(X509) *certs, |
| 369 |
X509_STORE *store, unsigned long flags) |
| 370 |
{ |
| 371 |
X509 *signer; |
| 372 |
X509_NAME *nm; |
| 373 |
GENERAL_NAME *gen; |
| 374 |
int ret; |
| 375 |
X509_STORE_CTX ctx; |
| 376 |
if (!req->optionalSignature) { |
| 377 |
OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_REQUEST_NOT_SIGNED); |
| 378 |
return 0; |
| 379 |
} |
| 380 |
gen = req->tbsRequest->requestorName; |
| 381 |
if (!gen || gen->type != GEN_DIRNAME) { |
| 382 |
OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, |
| 383 |
OCSP_R_UNSUPPORTED_REQUESTORNAME_TYPE); |
| 384 |
return 0; |
| 385 |
} |
| 386 |
nm = gen->d.directoryName; |
| 387 |
ret = ocsp_req_find_signer(&signer, req, nm, certs, store, flags); |
| 388 |
if (ret <= 0) { |
| 389 |
OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, |
| 390 |
OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND); |
| 391 |
return 0; |
| 392 |
} |
| 393 |
if ((ret == 2) && (flags & OCSP_TRUSTOTHER)) |
| 394 |
flags |= OCSP_NOVERIFY; |
| 395 |
if (!(flags & OCSP_NOSIGS)) { |
| 396 |
EVP_PKEY *skey; |
| 397 |
skey = X509_get_pubkey(signer); |
| 398 |
ret = OCSP_REQUEST_verify(req, skey); |
| 399 |
EVP_PKEY_free(skey); |
| 400 |
if (ret <= 0) { |
| 401 |
OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, OCSP_R_SIGNATURE_FAILURE); |
| 402 |
return 0; |
| 403 |
} |
| 404 |
} |
| 405 |
if (!(flags & OCSP_NOVERIFY)) { |
| 406 |
int init_res; |
| 407 |
if (flags & OCSP_NOCHAIN) |
| 408 |
init_res = X509_STORE_CTX_init(&ctx, store, signer, NULL); |
| 409 |
else |
| 410 |
init_res = X509_STORE_CTX_init(&ctx, store, signer, |
| 411 |
req->optionalSignature->certs); |
| 412 |
if (!init_res) { |
| 413 |
OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, ERR_R_X509_LIB); |
| 414 |
return 0; |
| 415 |
} |
| 416 |
|
| 417 |
X509_STORE_CTX_set_purpose(&ctx, X509_PURPOSE_OCSP_HELPER); |
| 418 |
X509_STORE_CTX_set_trust(&ctx, X509_TRUST_OCSP_REQUEST); |
| 419 |
ret = X509_verify_cert(&ctx); |
| 420 |
X509_STORE_CTX_cleanup(&ctx); |
| 421 |
if (ret <= 0) { |
| 422 |
ret = X509_STORE_CTX_get_error(&ctx); |
| 423 |
OCSPerr(OCSP_F_OCSP_REQUEST_VERIFY, |
| 424 |
OCSP_R_CERTIFICATE_VERIFY_ERROR); |
| 425 |
ERR_add_error_data(2, "Verify error:", |
| 426 |
X509_verify_cert_error_string(ret)); |
| 427 |
return 0; |
| 428 |
} |
| 429 |
} |
| 430 |
return 1; |
| 431 |
} |
| 432 |
|
| 433 |
static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req, |
| 434 |
X509_NAME *nm, STACK_OF(X509) *certs, |
| 435 |
X509_STORE *st, unsigned long flags) |
| 436 |
{ |
| 437 |
X509 *signer; |
| 438 |
if (!(flags & OCSP_NOINTERN)) { |
| 439 |
signer = X509_find_by_subject(req->optionalSignature->certs, nm); |
| 440 |
*psigner = signer; |
| 441 |
return 1; |
| 442 |
} |
| 443 |
|
| 444 |
signer = X509_find_by_subject(certs, nm); |
| 445 |
if (signer) { |
| 446 |
*psigner = signer; |
| 447 |
return 2; |
| 448 |
} |
| 449 |
return 0; |
| 450 |
} |
