441 lines
14 KiB
C
441 lines
14 KiB
C
/*
|
|
* Copyright 2001-2022 The OpenSSL Project Authors. All Rights Reserved.
|
|
*
|
|
* Licensed under the Apache License 2.0 (the "License"). You may not use
|
|
* this file except in compliance with the License. You can obtain a copy
|
|
* in the file LICENSE in the source distribution or at
|
|
* https://www.openssl.org/source/license.html
|
|
*/
|
|
|
|
#include <string.h>
|
|
#include <openssl/ocsp.h>
|
|
#include <openssl/err.h>
|
|
#include "internal/sizes.h"
|
|
#include "ocsp_local.h"
|
|
|
|
static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs,
|
|
STACK_OF(X509) *certs, unsigned long flags);
|
|
static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id);
|
|
static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain);
|
|
static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp,
|
|
OCSP_CERTID **ret);
|
|
static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid,
|
|
STACK_OF(OCSP_SINGLERESP) *sresp);
|
|
static int ocsp_check_delegated(X509 *x);
|
|
static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req,
|
|
const X509_NAME *nm, STACK_OF(X509) *certs,
|
|
unsigned long flags);
|
|
|
|
/* Returns 1 on success, 0 on failure, or -1 on fatal error */
|
|
static int ocsp_verify_signer(X509 *signer, int response,
|
|
X509_STORE *st, unsigned long flags,
|
|
STACK_OF(X509) *untrusted, STACK_OF(X509) **chain)
|
|
{
|
|
X509_STORE_CTX *ctx = X509_STORE_CTX_new();
|
|
X509_VERIFY_PARAM *vp;
|
|
int ret = -1;
|
|
|
|
if (ctx == NULL) {
|
|
ERR_raise(ERR_LIB_OCSP, ERR_R_X509_LIB);
|
|
goto end;
|
|
}
|
|
if (!X509_STORE_CTX_init(ctx, st, signer, untrusted)) {
|
|
ERR_raise(ERR_LIB_OCSP, ERR_R_X509_LIB);
|
|
goto end;
|
|
}
|
|
if ((vp = X509_STORE_CTX_get0_param(ctx)) == NULL)
|
|
goto end;
|
|
if ((flags & OCSP_PARTIAL_CHAIN) != 0)
|
|
X509_VERIFY_PARAM_set_flags(vp, X509_V_FLAG_PARTIAL_CHAIN);
|
|
if (response
|
|
&& X509_get_ext_by_NID(signer, NID_id_pkix_OCSP_noCheck, -1) >= 0)
|
|
/*
|
|
* Locally disable revocation status checking for OCSP responder cert.
|
|
* Done here for CRLs; should be done also for OCSP-based checks.
|
|
*/
|
|
X509_VERIFY_PARAM_clear_flags(vp, X509_V_FLAG_CRL_CHECK);
|
|
X509_STORE_CTX_set_purpose(ctx, X509_PURPOSE_OCSP_HELPER);
|
|
X509_STORE_CTX_set_trust(ctx, X509_TRUST_OCSP_REQUEST);
|
|
|
|
ret = X509_verify_cert(ctx);
|
|
if (ret <= 0) {
|
|
int err = X509_STORE_CTX_get_error(ctx);
|
|
|
|
ERR_raise_data(ERR_LIB_OCSP, OCSP_R_CERTIFICATE_VERIFY_ERROR,
|
|
"Verify error: %s", X509_verify_cert_error_string(err));
|
|
goto end;
|
|
}
|
|
if (chain != NULL)
|
|
*chain = X509_STORE_CTX_get1_chain(ctx);
|
|
|
|
end:
|
|
X509_STORE_CTX_free(ctx);
|
|
return ret;
|
|
}
|
|
|
|
static int ocsp_verify(OCSP_REQUEST *req, OCSP_BASICRESP *bs,
|
|
X509 *signer, unsigned long flags)
|
|
{
|
|
EVP_PKEY *skey;
|
|
int ret = 1;
|
|
|
|
if ((flags & OCSP_NOSIGS) == 0) {
|
|
if ((skey = X509_get0_pubkey(signer)) == NULL) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_NO_SIGNER_KEY);
|
|
return -1;
|
|
}
|
|
if (req != NULL)
|
|
ret = OCSP_REQUEST_verify(req, skey, signer->libctx, signer->propq);
|
|
else
|
|
ret = OCSP_BASICRESP_verify(bs, skey, signer->libctx, signer->propq);
|
|
if (ret <= 0)
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_SIGNATURE_FAILURE);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/* Verify a basic response message */
|
|
int OCSP_basic_verify(OCSP_BASICRESP *bs, STACK_OF(X509) *certs,
|
|
X509_STORE *st, unsigned long flags)
|
|
{
|
|
X509 *signer, *x;
|
|
STACK_OF(X509) *chain = NULL;
|
|
STACK_OF(X509) *untrusted = NULL;
|
|
int ret = ocsp_find_signer(&signer, bs, certs, flags);
|
|
|
|
if (ret == 0) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND);
|
|
goto end;
|
|
}
|
|
if ((ret == 2) && (flags & OCSP_TRUSTOTHER) != 0)
|
|
flags |= OCSP_NOVERIFY;
|
|
|
|
if ((ret = ocsp_verify(NULL, bs, signer, flags)) <= 0)
|
|
goto end;
|
|
if ((flags & OCSP_NOVERIFY) == 0) {
|
|
ret = -1;
|
|
if ((flags & OCSP_NOCHAIN) == 0) {
|
|
if ((untrusted = sk_X509_dup(bs->certs)) == NULL)
|
|
goto end;
|
|
if (!X509_add_certs(untrusted, certs, X509_ADD_FLAG_DEFAULT))
|
|
goto end;
|
|
}
|
|
ret = ocsp_verify_signer(signer, 1, st, flags, untrusted, &chain);
|
|
if (ret <= 0)
|
|
goto end;
|
|
if ((flags & OCSP_NOCHECKS) != 0) {
|
|
ret = 1;
|
|
goto end;
|
|
}
|
|
/*
|
|
* At this point we have a valid certificate chain need to verify it
|
|
* against the OCSP issuer criteria.
|
|
*/
|
|
ret = ocsp_check_issuer(bs, chain);
|
|
|
|
/* If fatal error or valid match then finish */
|
|
if (ret != 0)
|
|
goto end;
|
|
|
|
/*
|
|
* Easy case: explicitly trusted. Get root CA and check for explicit
|
|
* trust
|
|
*/
|
|
if ((flags & OCSP_NOEXPLICIT) != 0)
|
|
goto end;
|
|
|
|
x = sk_X509_value(chain, sk_X509_num(chain) - 1);
|
|
if (X509_check_trust(x, NID_OCSP_sign, 0) != X509_TRUST_TRUSTED) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_ROOT_CA_NOT_TRUSTED);
|
|
ret = 0;
|
|
goto end;
|
|
}
|
|
ret = 1;
|
|
}
|
|
|
|
end:
|
|
OSSL_STACK_OF_X509_free(chain);
|
|
sk_X509_free(untrusted);
|
|
return ret;
|
|
}
|
|
|
|
int OCSP_resp_get0_signer(OCSP_BASICRESP *bs, X509 **signer,
|
|
STACK_OF(X509) *extra_certs)
|
|
{
|
|
return ocsp_find_signer(signer, bs, extra_certs, 0) > 0;
|
|
}
|
|
|
|
static int ocsp_find_signer(X509 **psigner, OCSP_BASICRESP *bs,
|
|
STACK_OF(X509) *certs, unsigned long flags)
|
|
{
|
|
X509 *signer;
|
|
OCSP_RESPID *rid = &bs->tbsResponseData.responderId;
|
|
|
|
if ((signer = ocsp_find_signer_sk(certs, rid)) != NULL) {
|
|
*psigner = signer;
|
|
return 2;
|
|
}
|
|
if ((flags & OCSP_NOINTERN) == 0 &&
|
|
(signer = ocsp_find_signer_sk(bs->certs, rid))) {
|
|
*psigner = signer;
|
|
return 1;
|
|
}
|
|
/* Maybe lookup from store if by subject name */
|
|
|
|
*psigner = NULL;
|
|
return 0;
|
|
}
|
|
|
|
static X509 *ocsp_find_signer_sk(STACK_OF(X509) *certs, OCSP_RESPID *id)
|
|
{
|
|
int i, r;
|
|
unsigned char tmphash[SHA_DIGEST_LENGTH], *keyhash;
|
|
EVP_MD *md;
|
|
X509 *x;
|
|
|
|
/* Easy if lookup by name */
|
|
if (id->type == V_OCSP_RESPID_NAME)
|
|
return X509_find_by_subject(certs, id->value.byName);
|
|
|
|
/* Lookup by key hash */
|
|
|
|
/* If key hash isn't SHA1 length then forget it */
|
|
if (id->value.byKey->length != SHA_DIGEST_LENGTH)
|
|
return NULL;
|
|
keyhash = id->value.byKey->data;
|
|
/* Calculate hash of each key and compare */
|
|
for (i = 0; i < sk_X509_num(certs); i++) {
|
|
if ((x = sk_X509_value(certs, i)) != NULL) {
|
|
if ((md = EVP_MD_fetch(x->libctx, SN_sha1, x->propq)) == NULL)
|
|
break;
|
|
r = X509_pubkey_digest(x, md, tmphash, NULL);
|
|
EVP_MD_free(md);
|
|
if (!r)
|
|
break;
|
|
if (memcmp(keyhash, tmphash, SHA_DIGEST_LENGTH) == 0)
|
|
return x;
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static int ocsp_check_issuer(OCSP_BASICRESP *bs, STACK_OF(X509) *chain)
|
|
{
|
|
STACK_OF(OCSP_SINGLERESP) *sresp = bs->tbsResponseData.responses;
|
|
X509 *signer, *sca;
|
|
OCSP_CERTID *caid = NULL;
|
|
int ret;
|
|
|
|
if (sk_X509_num(chain) <= 0) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_NO_CERTIFICATES_IN_CHAIN);
|
|
return -1;
|
|
}
|
|
|
|
/* See if the issuer IDs match. */
|
|
ret = ocsp_check_ids(sresp, &caid);
|
|
|
|
/* If ID mismatch or other error then return */
|
|
if (ret <= 0)
|
|
return ret;
|
|
|
|
signer = sk_X509_value(chain, 0);
|
|
/* Check to see if OCSP responder CA matches request CA */
|
|
if (sk_X509_num(chain) > 1) {
|
|
sca = sk_X509_value(chain, 1);
|
|
ret = ocsp_match_issuerid(sca, caid, sresp);
|
|
if (ret < 0)
|
|
return ret;
|
|
if (ret != 0) {
|
|
/* We have a match, if extensions OK then success */
|
|
if (ocsp_check_delegated(signer))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* Otherwise check if OCSP request signed directly by request CA */
|
|
return ocsp_match_issuerid(signer, caid, sresp);
|
|
}
|
|
|
|
/*
|
|
* Check the issuer certificate IDs for equality. If there is a mismatch with
|
|
* the same algorithm then there's no point trying to match any certificates
|
|
* against the issuer. If the issuer IDs all match then we just need to check
|
|
* equality against one of them.
|
|
*/
|
|
|
|
static int ocsp_check_ids(STACK_OF(OCSP_SINGLERESP) *sresp, OCSP_CERTID **ret)
|
|
{
|
|
OCSP_CERTID *tmpid, *cid;
|
|
int i, idcount;
|
|
|
|
idcount = sk_OCSP_SINGLERESP_num(sresp);
|
|
if (idcount <= 0) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_RESPONSE_CONTAINS_NO_REVOCATION_DATA);
|
|
return -1;
|
|
}
|
|
|
|
cid = sk_OCSP_SINGLERESP_value(sresp, 0)->certId;
|
|
|
|
*ret = NULL;
|
|
for (i = 1; i < idcount; i++) {
|
|
tmpid = sk_OCSP_SINGLERESP_value(sresp, i)->certId;
|
|
/* Check to see if IDs match */
|
|
if (OCSP_id_issuer_cmp(cid, tmpid)) {
|
|
/* If algorithm mismatch let caller deal with it */
|
|
if (OBJ_cmp(tmpid->hashAlgorithm.algorithm,
|
|
cid->hashAlgorithm.algorithm))
|
|
return 2;
|
|
/* Else mismatch */
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* All IDs match: only need to check one ID */
|
|
*ret = cid;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Match the certificate issuer ID.
|
|
* Returns -1 on fatal error, 0 if there is no match and 1 if there is a match.
|
|
*/
|
|
static int ocsp_match_issuerid(X509 *cert, OCSP_CERTID *cid,
|
|
STACK_OF(OCSP_SINGLERESP) *sresp)
|
|
{
|
|
int ret = -1;
|
|
EVP_MD *dgst = NULL;
|
|
|
|
/* If only one ID to match then do it */
|
|
if (cid != NULL) {
|
|
char name[OSSL_MAX_NAME_SIZE];
|
|
const X509_NAME *iname;
|
|
int mdlen;
|
|
unsigned char md[EVP_MAX_MD_SIZE];
|
|
|
|
OBJ_obj2txt(name, sizeof(name), cid->hashAlgorithm.algorithm, 0);
|
|
|
|
(void)ERR_set_mark();
|
|
dgst = EVP_MD_fetch(NULL, name, NULL);
|
|
if (dgst == NULL)
|
|
dgst = (EVP_MD *)EVP_get_digestbyname(name);
|
|
|
|
if (dgst == NULL) {
|
|
(void)ERR_clear_last_mark();
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_UNKNOWN_MESSAGE_DIGEST);
|
|
goto end;
|
|
}
|
|
(void)ERR_pop_to_mark();
|
|
|
|
mdlen = EVP_MD_get_size(dgst);
|
|
if (mdlen < 0) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_DIGEST_SIZE_ERR);
|
|
goto end;
|
|
}
|
|
if (cid->issuerNameHash.length != mdlen ||
|
|
cid->issuerKeyHash.length != mdlen) {
|
|
ret = 0;
|
|
goto end;
|
|
}
|
|
iname = X509_get_subject_name(cert);
|
|
if (!X509_NAME_digest(iname, dgst, md, NULL))
|
|
goto end;
|
|
if (memcmp(md, cid->issuerNameHash.data, mdlen) != 0) {
|
|
ret = 0;
|
|
goto end;
|
|
}
|
|
if (!X509_pubkey_digest(cert, dgst, md, NULL)) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_DIGEST_ERR);
|
|
goto end;
|
|
}
|
|
ret = memcmp(md, cid->issuerKeyHash.data, mdlen) == 0;
|
|
goto end;
|
|
} else {
|
|
/* We have to match the whole lot */
|
|
int i;
|
|
OCSP_CERTID *tmpid;
|
|
|
|
for (i = 0; i < sk_OCSP_SINGLERESP_num(sresp); i++) {
|
|
tmpid = sk_OCSP_SINGLERESP_value(sresp, i)->certId;
|
|
ret = ocsp_match_issuerid(cert, tmpid, NULL);
|
|
if (ret <= 0)
|
|
return ret;
|
|
}
|
|
}
|
|
return 1;
|
|
end:
|
|
EVP_MD_free(dgst);
|
|
return ret;
|
|
}
|
|
|
|
static int ocsp_check_delegated(X509 *x)
|
|
{
|
|
if ((X509_get_extension_flags(x) & EXFLAG_XKUSAGE)
|
|
&& (X509_get_extended_key_usage(x) & XKU_OCSP_SIGN))
|
|
return 1;
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_MISSING_OCSPSIGNING_USAGE);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Verify an OCSP request. This is much easier than OCSP response verify.
|
|
* Just find the signer's certificate and verify it against a given trust value.
|
|
* Returns 1 on success, 0 on failure and on fatal error.
|
|
*/
|
|
int OCSP_request_verify(OCSP_REQUEST *req, STACK_OF(X509) *certs,
|
|
X509_STORE *store, unsigned long flags)
|
|
{
|
|
X509 *signer;
|
|
const X509_NAME *nm;
|
|
GENERAL_NAME *gen;
|
|
int ret;
|
|
|
|
if (!req->optionalSignature) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_REQUEST_NOT_SIGNED);
|
|
return 0;
|
|
}
|
|
gen = req->tbsRequest.requestorName;
|
|
if (!gen || gen->type != GEN_DIRNAME) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_UNSUPPORTED_REQUESTORNAME_TYPE);
|
|
return 0; /* not returning -1 here for backward compatibility*/
|
|
}
|
|
nm = gen->d.directoryName;
|
|
ret = ocsp_req_find_signer(&signer, req, nm, certs, flags);
|
|
if (ret <= 0) {
|
|
ERR_raise(ERR_LIB_OCSP, OCSP_R_SIGNER_CERTIFICATE_NOT_FOUND);
|
|
return 0; /* not returning -1 here for backward compatibility*/
|
|
}
|
|
if ((ret == 2) && (flags & OCSP_TRUSTOTHER) != 0)
|
|
flags |= OCSP_NOVERIFY;
|
|
|
|
if ((ret = ocsp_verify(req, NULL, signer, flags)) <= 0)
|
|
return 0; /* not returning 'ret' here for backward compatibility*/
|
|
if ((flags & OCSP_NOVERIFY) != 0)
|
|
return 1;
|
|
return ocsp_verify_signer(signer, 0, store, flags,
|
|
(flags & OCSP_NOCHAIN) != 0 ?
|
|
NULL : req->optionalSignature->certs, NULL) > 0;
|
|
/* using '> 0' here to avoid breaking backward compatibility returning -1 */
|
|
}
|
|
|
|
static int ocsp_req_find_signer(X509 **psigner, OCSP_REQUEST *req,
|
|
const X509_NAME *nm, STACK_OF(X509) *certs,
|
|
unsigned long flags)
|
|
{
|
|
X509 *signer;
|
|
|
|
if ((flags & OCSP_NOINTERN) == 0) {
|
|
signer = X509_find_by_subject(req->optionalSignature->certs, nm);
|
|
if (signer != NULL) {
|
|
*psigner = signer;
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
if ((signer = X509_find_by_subject(certs, nm)) != NULL) {
|
|
*psigner = signer;
|
|
return 2;
|
|
}
|
|
return 0;
|
|
}
|