crypto/ocsp/ocsp_cl.c - third_party/openssl - Git at Google

 /* ocsp_cl.c */
 /*
  * Written by Tom Titchener <Tom_Titchener@groove.net> for the OpenSSL
  * project.
  */

 /*
  * History: This file was transfered to Richard Levitte from CertCo by Kathy
  * Weinhold in mid-spring 2000 to be included in OpenSSL or released as a
  * patch kit.
  */

 /* ====================================================================
  * Copyright (c) 1998-2000 The OpenSSL Project.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  *
  * 3. All advertising materials mentioning features or use of this
  *    software must display the following acknowledgment:
  *    "This product includes software developed by the OpenSSL Project
  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  *
  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  *    endorse or promote products derived from this software without
  *    prior written permission. For written permission, please contact
  *    openssl-core@openssl.org.
  *
  * 5. Products derived from this software may not be called "OpenSSL"
  *    nor may "OpenSSL" appear in their names without prior written
  *    permission of the OpenSSL Project.
  *
  * 6. Redistributions of any form whatsoever must retain the following
  *    acknowledgment:
  *    "This product includes software developed by the OpenSSL Project
  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  *
  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  * ====================================================================
  *
  * This product includes cryptographic software written by Eric Young
  * (eay@cryptsoft.com).  This product includes software written by Tim
  * Hudson (tjh@cryptsoft.com).
  *
  */

 #include <stdio.h>
 #include <time.h>
 #include <cryptlib.h>
 #include <openssl/objects.h>
 #include <openssl/rand.h>
 #include <openssl/x509.h>
 #include <openssl/pem.h>
 #include <openssl/x509v3.h>
 #include <openssl/ocsp.h>

 /*
  * Utility functions related to sending OCSP requests and extracting relevant
  * information from the response.
  */

 /*
  * Add an OCSP_CERTID to an OCSP request. Return new OCSP_ONEREQ pointer:
  * useful if we want to add extensions.
  */

 OCSP_ONEREQ *OCSP_request_add0_id(OCSP_REQUEST *req, OCSP_CERTID *cid)
 {
     OCSP_ONEREQ *one = NULL;

     if (!(one = OCSP_ONEREQ_new()))
         goto err;
     if (one->reqCert)
         OCSP_CERTID_free(one->reqCert);
     one->reqCert = cid;
     if (req && !sk_OCSP_ONEREQ_push(req->tbsRequest->requestList, one))
         goto err;
     return one;
  err:
     OCSP_ONEREQ_free(one);
     return NULL;
 }

 /* Set requestorName from an X509_NAME structure */

 int OCSP_request_set1_name(OCSP_REQUEST *req, X509_NAME *nm)
 {
     GENERAL_NAME *gen;
     gen = GENERAL_NAME_new();
     if (gen == NULL)
         return 0;
     if (!X509_NAME_set(&gen->d.directoryName, nm)) {
         GENERAL_NAME_free(gen);
         return 0;
     }
     gen->type = GEN_DIRNAME;
     if (req->tbsRequest->requestorName)
         GENERAL_NAME_free(req->tbsRequest->requestorName);
     req->tbsRequest->requestorName = gen;
     return 1;
 }

 /* Add a certificate to an OCSP request */

 int OCSP_request_add1_cert(OCSP_REQUEST *req, X509 *cert)
 {
     OCSP_SIGNATURE *sig;
     if (!req->optionalSignature)
         req->optionalSignature = OCSP_SIGNATURE_new();
     sig = req->optionalSignature;
     if (!sig)
         return 0;
     if (!cert)
         return 1;
     if (!sig->certs && !(sig->certs = sk_X509_new_null()))
         return 0;

     if (!sk_X509_push(sig->certs, cert))
         return 0;
     CRYPTO_add(&cert->references, 1, CRYPTO_LOCK_X509);
     return 1;
 }

 /*
  * Sign an OCSP request set the requestorName to the subjec name of an
  * optional signers certificate and include one or more optional certificates
  * in the request. Behaves like PKCS7_sign().
  */

 int OCSP_request_sign(OCSP_REQUEST *req,
                       X509 *signer,
                       EVP_PKEY *key,
                       const EVP_MD *dgst,
                       STACK_OF(X509) *certs, unsigned long flags)
 {
     int i;
     X509 *x;

     if (!OCSP_request_set1_name(req, X509_get_subject_name(signer)))
         goto err;

     if (!(req->optionalSignature = OCSP_SIGNATURE_new()))
         goto err;
     if (key) {
         if (!X509_check_private_key(signer, key)) {
             OCSPerr(OCSP_F_OCSP_REQUEST_SIGN,
                     OCSP_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
             goto err;
         }
         if (!OCSP_REQUEST_sign(req, key, dgst))
             goto err;
     }

     if (!(flags & OCSP_NOCERTS)) {
         if (!OCSP_request_add1_cert(req, signer))
             goto err;
         for (i = 0; i < sk_X509_num(certs); i++) {
             x = sk_X509_value(certs, i);
             if (!OCSP_request_add1_cert(req, x))
                 goto err;
         }
     }

     return 1;
  err:
     OCSP_SIGNATURE_free(req->optionalSignature);
     req->optionalSignature = NULL;
     return 0;
 }

 /* Get response status */

 int OCSP_response_status(OCSP_RESPONSE *resp)
 {
     return ASN1_ENUMERATED_get(resp->responseStatus);
 }

 /*
  * Extract basic response from OCSP_RESPONSE or NULL if no basic response
  * present.
  */

 OCSP_BASICRESP *OCSP_response_get1_basic(OCSP_RESPONSE *resp)
 {
     OCSP_RESPBYTES *rb;
     rb = resp->responseBytes;
     if (!rb) {
         OCSPerr(OCSP_F_OCSP_RESPONSE_GET1_BASIC, OCSP_R_NO_RESPONSE_DATA);
         return NULL;
     }
     if (OBJ_obj2nid(rb->responseType) != NID_id_pkix_OCSP_basic) {
         OCSPerr(OCSP_F_OCSP_RESPONSE_GET1_BASIC, OCSP_R_NOT_BASIC_RESPONSE);
         return NULL;
     }

     return ASN1_item_unpack(rb->response, ASN1_ITEM_rptr(OCSP_BASICRESP));
 }

 /*
  * Return number of OCSP_SINGLERESP reponses present in a basic response.
  */

 int OCSP_resp_count(OCSP_BASICRESP *bs)
 {
     if (!bs)
         return -1;
     return sk_OCSP_SINGLERESP_num(bs->tbsResponseData->responses);
 }

 /* Extract an OCSP_SINGLERESP response with a given index */

 OCSP_SINGLERESP *OCSP_resp_get0(OCSP_BASICRESP *bs, int idx)
 {
     if (!bs)
         return NULL;
     return sk_OCSP_SINGLERESP_value(bs->tbsResponseData->responses, idx);
 }

 /* Look single response matching a given certificate ID */

 int OCSP_resp_find(OCSP_BASICRESP *bs, OCSP_CERTID *id, int last)
 {
     int i;
     STACK_OF(OCSP_SINGLERESP) *sresp;
     OCSP_SINGLERESP *single;
     if (!bs)
         return -1;
     if (last < 0)
         last = 0;
     else
         last++;
     sresp = bs->tbsResponseData->responses;
     for (i = last; i < sk_OCSP_SINGLERESP_num(sresp); i++) {
         single = sk_OCSP_SINGLERESP_value(sresp, i);
         if (!OCSP_id_cmp(id, single->certId))
             return i;
     }
     return -1;
 }

 /*
  * Extract status information from an OCSP_SINGLERESP structure. Note: the
  * revtime and reason values are only set if the certificate status is
  * revoked. Returns numerical value of status.
  */

 int OCSP_single_get0_status(OCSP_SINGLERESP *single, int *reason,
                             ASN1_GENERALIZEDTIME **revtime,
                             ASN1_GENERALIZEDTIME **thisupd,
                             ASN1_GENERALIZEDTIME **nextupd)
 {
     int ret;
     OCSP_CERTSTATUS *cst;
     if (!single)
         return -1;
     cst = single->certStatus;
     ret = cst->type;
     if (ret == V_OCSP_CERTSTATUS_REVOKED) {
         OCSP_REVOKEDINFO *rev = cst->value.revoked;
         if (revtime)
             *revtime = rev->revocationTime;
         if (reason) {
             if (rev->revocationReason)
                 *reason = ASN1_ENUMERATED_get(rev->revocationReason);
             else
                 *reason = -1;
         }
     }
     if (thisupd)
         *thisupd = single->thisUpdate;
     if (nextupd)
         *nextupd = single->nextUpdate;
     return ret;
 }

 /*
  * This function combines the previous ones: look up a certificate ID and if
  * found extract status information. Return 0 is successful.
  */

 int OCSP_resp_find_status(OCSP_BASICRESP *bs, OCSP_CERTID *id, int *status,
                           int *reason,
                           ASN1_GENERALIZEDTIME **revtime,
                           ASN1_GENERALIZEDTIME **thisupd,
                           ASN1_GENERALIZEDTIME **nextupd)
 {
     int i;
     OCSP_SINGLERESP *single;
     i = OCSP_resp_find(bs, id, -1);
     /* Maybe check for multiple responses and give an error? */
     if (i < 0)
         return 0;
     single = OCSP_resp_get0(bs, i);
     i = OCSP_single_get0_status(single, reason, revtime, thisupd, nextupd);
     if (status)
         *status = i;
     return 1;
 }

 /*
  * Check validity of thisUpdate and nextUpdate fields. It is possible that
  * the request will take a few seconds to process and/or the time wont be
  * totally accurate. Therefore to avoid rejecting otherwise valid time we
  * allow the times to be within 'nsec' of the current time. Also to avoid
  * accepting very old responses without a nextUpdate field an optional maxage
  * parameter specifies the maximum age the thisUpdate field can be.
  */

 int OCSP_check_validity(ASN1_GENERALIZEDTIME *thisupd,
                         ASN1_GENERALIZEDTIME *nextupd, long nsec, long maxsec)
 {
     int ret = 1;
     time_t t_now, t_tmp;
     time(&t_now);
     /* Check thisUpdate is valid and not more than nsec in the future */
     if (!ASN1_GENERALIZEDTIME_check(thisupd)) {
         OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_ERROR_IN_THISUPDATE_FIELD);
         ret = 0;
     } else {
         t_tmp = t_now + nsec;
         if (X509_cmp_time(thisupd, &t_tmp) > 0) {
             OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_STATUS_NOT_YET_VALID);
             ret = 0;
         }

         /*
          * If maxsec specified check thisUpdate is not more than maxsec in
          * the past
          */
         if (maxsec >= 0) {
             t_tmp = t_now - maxsec;
             if (X509_cmp_time(thisupd, &t_tmp) < 0) {
                 OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_STATUS_TOO_OLD);
                 ret = 0;
             }
         }
     }

     if (!nextupd)
         return ret;

     /* Check nextUpdate is valid and not more than nsec in the past */
     if (!ASN1_GENERALIZEDTIME_check(nextupd)) {
         OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_ERROR_IN_NEXTUPDATE_FIELD);
         ret = 0;
     } else {
         t_tmp = t_now - nsec;
         if (X509_cmp_time(nextupd, &t_tmp) < 0) {
             OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_STATUS_EXPIRED);
             ret = 0;
         }
     }

     /* Also don't allow nextUpdate to precede thisUpdate */
     if (ASN1_STRING_cmp(nextupd, thisupd) < 0) {
         OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY,
                 OCSP_R_NEXTUPDATE_BEFORE_THISUPDATE);
         ret = 0;
     }

     return ret;
 }
	/* ocsp_cl.c */
	/*
	* Written by Tom Titchener <Tom_Titchener@groove.net> for the OpenSSL
	* project.
	*/

	/*
	* History: This file was transfered to Richard Levitte from CertCo by Kathy
	* Weinhold in mid-spring 2000 to be included in OpenSSL or released as a
	* patch kit.
	*/

	/* ====================================================================
	* Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	*
	* 3. All advertising materials mentioning features or use of this
	* software must display the following acknowledgment:
	* "This product includes software developed by the OpenSSL Project
	* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
	*
	* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
	* endorse or promote products derived from this software without
	* prior written permission. For written permission, please contact
	* openssl-core@openssl.org.
	*
	* 5. Products derived from this software may not be called "OpenSSL"
	* nor may "OpenSSL" appear in their names without prior written
	* permission of the OpenSSL Project.
	*
	* 6. Redistributions of any form whatsoever must retain the following
	* acknowledgment:
	* "This product includes software developed by the OpenSSL Project
	* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
	*
	* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
	* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
	* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
	* OF THE POSSIBILITY OF SUCH DAMAGE.
	* ====================================================================
	*
	* This product includes cryptographic software written by Eric Young
	* (eay@cryptsoft.com). This product includes software written by Tim
	* Hudson (tjh@cryptsoft.com).
	*
	*/

	#include <stdio.h>
	#include <time.h>
	#include <cryptlib.h>
	#include <openssl/objects.h>
	#include <openssl/rand.h>
	#include <openssl/x509.h>
	#include <openssl/pem.h>
	#include <openssl/x509v3.h>
	#include <openssl/ocsp.h>

	/*
	* Utility functions related to sending OCSP requests and extracting relevant
	* information from the response.
	*/

	/*
	* Add an OCSP_CERTID to an OCSP request. Return new OCSP_ONEREQ pointer:
	* useful if we want to add extensions.
	*/

	OCSP_ONEREQ OCSP_request_add0_id(OCSP_REQUEST req, OCSP_CERTID *cid)
	{
	OCSP_ONEREQ *one = NULL;

	if (!(one = OCSP_ONEREQ_new()))
	goto err;
	if (one->reqCert)
	OCSP_CERTID_free(one->reqCert);
	one->reqCert = cid;
	if (req && !sk_OCSP_ONEREQ_push(req->tbsRequest->requestList, one))
	goto err;
	return one;
	err:
	OCSP_ONEREQ_free(one);
	return NULL;
	}

	/* Set requestorName from an X509_NAME structure */

	int OCSP_request_set1_name(OCSP_REQUEST req, X509_NAME nm)
	{
	GENERAL_NAME *gen;
	gen = GENERAL_NAME_new();
	if (gen == NULL)
	return 0;
	if (!X509_NAME_set(&gen->d.directoryName, nm)) {
	GENERAL_NAME_free(gen);
	return 0;
	}
	gen->type = GEN_DIRNAME;
	if (req->tbsRequest->requestorName)
	GENERAL_NAME_free(req->tbsRequest->requestorName);
	req->tbsRequest->requestorName = gen;
	return 1;
	}

	/* Add a certificate to an OCSP request */

	int OCSP_request_add1_cert(OCSP_REQUEST req, X509 cert)
	{
	OCSP_SIGNATURE *sig;
	if (!req->optionalSignature)
	req->optionalSignature = OCSP_SIGNATURE_new();
	sig = req->optionalSignature;
	if (!sig)
	return 0;
	if (!cert)
	return 1;
	if (!sig->certs && !(sig->certs = sk_X509_new_null()))
	return 0;

	if (!sk_X509_push(sig->certs, cert))
	return 0;
	CRYPTO_add(&cert->references, 1, CRYPTO_LOCK_X509);
	return 1;
	}

	/*
	* Sign an OCSP request set the requestorName to the subjec name of an
	* optional signers certificate and include one or more optional certificates
	* in the request. Behaves like PKCS7_sign().
	*/

	int OCSP_request_sign(OCSP_REQUEST *req,
	X509 *signer,
	EVP_PKEY *key,
	const EVP_MD *dgst,
	STACK_OF(X509) *certs, unsigned long flags)
	{
	int i;
	X509 *x;

	if (!OCSP_request_set1_name(req, X509_get_subject_name(signer)))
	goto err;

	if (!(req->optionalSignature = OCSP_SIGNATURE_new()))
	goto err;
	if (key) {
	if (!X509_check_private_key(signer, key)) {
	OCSPerr(OCSP_F_OCSP_REQUEST_SIGN,
	OCSP_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);
	goto err;
	}
	if (!OCSP_REQUEST_sign(req, key, dgst))
	goto err;
	}

	if (!(flags & OCSP_NOCERTS)) {
	if (!OCSP_request_add1_cert(req, signer))
	goto err;
	for (i = 0; i < sk_X509_num(certs); i++) {
	x = sk_X509_value(certs, i);
	if (!OCSP_request_add1_cert(req, x))
	goto err;
	}
	}

	return 1;
	err:
	OCSP_SIGNATURE_free(req->optionalSignature);
	req->optionalSignature = NULL;
	return 0;
	}

	/* Get response status */

	int OCSP_response_status(OCSP_RESPONSE *resp)
	{
	return ASN1_ENUMERATED_get(resp->responseStatus);
	}

	/*
	* Extract basic response from OCSP_RESPONSE or NULL if no basic response
	* present.
	*/

	OCSP_BASICRESP OCSP_response_get1_basic(OCSP_RESPONSE resp)
	{
	OCSP_RESPBYTES *rb;
	rb = resp->responseBytes;
	if (!rb) {
	OCSPerr(OCSP_F_OCSP_RESPONSE_GET1_BASIC, OCSP_R_NO_RESPONSE_DATA);
	return NULL;
	}
	if (OBJ_obj2nid(rb->responseType) != NID_id_pkix_OCSP_basic) {
	OCSPerr(OCSP_F_OCSP_RESPONSE_GET1_BASIC, OCSP_R_NOT_BASIC_RESPONSE);
	return NULL;
	}

	return ASN1_item_unpack(rb->response, ASN1_ITEM_rptr(OCSP_BASICRESP));
	}

	/*
	* Return number of OCSP_SINGLERESP reponses present in a basic response.
	*/

	int OCSP_resp_count(OCSP_BASICRESP *bs)
	{
	if (!bs)
	return -1;
	return sk_OCSP_SINGLERESP_num(bs->tbsResponseData->responses);
	}

	/* Extract an OCSP_SINGLERESP response with a given index */

	OCSP_SINGLERESP OCSP_resp_get0(OCSP_BASICRESP bs, int idx)
	{
	if (!bs)
	return NULL;
	return sk_OCSP_SINGLERESP_value(bs->tbsResponseData->responses, idx);
	}

	/* Look single response matching a given certificate ID */

	int OCSP_resp_find(OCSP_BASICRESP bs, OCSP_CERTID id, int last)
	{
	int i;
	STACK_OF(OCSP_SINGLERESP) *sresp;
	OCSP_SINGLERESP *single;
	if (!bs)
	return -1;
	if (last < 0)
	last = 0;
	else
	last++;
	sresp = bs->tbsResponseData->responses;
	for (i = last; i < sk_OCSP_SINGLERESP_num(sresp); i++) {
	single = sk_OCSP_SINGLERESP_value(sresp, i);
	if (!OCSP_id_cmp(id, single->certId))
	return i;
	}
	return -1;
	}

	/*
	* Extract status information from an OCSP_SINGLERESP structure. Note: the
	* revtime and reason values are only set if the certificate status is
	* revoked. Returns numerical value of status.
	*/

	int OCSP_single_get0_status(OCSP_SINGLERESP single, int reason,
	ASN1_GENERALIZEDTIME **revtime,
	ASN1_GENERALIZEDTIME **thisupd,
	ASN1_GENERALIZEDTIME **nextupd)
	{
	int ret;
	OCSP_CERTSTATUS *cst;
	if (!single)
	return -1;
	cst = single->certStatus;
	ret = cst->type;
	if (ret == V_OCSP_CERTSTATUS_REVOKED) {
	OCSP_REVOKEDINFO *rev = cst->value.revoked;
	if (revtime)
	*revtime = rev->revocationTime;
	if (reason) {
	if (rev->revocationReason)
	*reason = ASN1_ENUMERATED_get(rev->revocationReason);
	else
	*reason = -1;
	}
	}
	if (thisupd)
	*thisupd = single->thisUpdate;
	if (nextupd)
	*nextupd = single->nextUpdate;
	return ret;
	}

	/*
	* This function combines the previous ones: look up a certificate ID and if
	* found extract status information. Return 0 is successful.
	*/

	int OCSP_resp_find_status(OCSP_BASICRESP bs, OCSP_CERTID id, int *status,
	int *reason,
	ASN1_GENERALIZEDTIME **revtime,
	ASN1_GENERALIZEDTIME **thisupd,
	ASN1_GENERALIZEDTIME **nextupd)
	{
	int i;
	OCSP_SINGLERESP *single;
	i = OCSP_resp_find(bs, id, -1);
	/* Maybe check for multiple responses and give an error? */
	if (i < 0)
	return 0;
	single = OCSP_resp_get0(bs, i);
	i = OCSP_single_get0_status(single, reason, revtime, thisupd, nextupd);
	if (status)
	*status = i;
	return 1;
	}

	/*
	* Check validity of thisUpdate and nextUpdate fields. It is possible that
	* the request will take a few seconds to process and/or the time wont be
	* totally accurate. Therefore to avoid rejecting otherwise valid time we
	* allow the times to be within 'nsec' of the current time. Also to avoid
	* accepting very old responses without a nextUpdate field an optional maxage
	* parameter specifies the maximum age the thisUpdate field can be.
	*/

	int OCSP_check_validity(ASN1_GENERALIZEDTIME *thisupd,
	ASN1_GENERALIZEDTIME *nextupd, long nsec, long maxsec)
	{
	int ret = 1;
	time_t t_now, t_tmp;
	time(&t_now);
	/* Check thisUpdate is valid and not more than nsec in the future */
	if (!ASN1_GENERALIZEDTIME_check(thisupd)) {
	OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_ERROR_IN_THISUPDATE_FIELD);
	ret = 0;
	} else {
	t_tmp = t_now + nsec;
	if (X509_cmp_time(thisupd, &t_tmp) > 0) {
	OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_STATUS_NOT_YET_VALID);
	ret = 0;
	}

	/*
	* If maxsec specified check thisUpdate is not more than maxsec in
	* the past
	*/
	if (maxsec >= 0) {
	t_tmp = t_now - maxsec;
	if (X509_cmp_time(thisupd, &t_tmp) < 0) {
	OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_STATUS_TOO_OLD);
	ret = 0;
	}
	}
	}

	if (!nextupd)
	return ret;

	/* Check nextUpdate is valid and not more than nsec in the past */
	if (!ASN1_GENERALIZEDTIME_check(nextupd)) {
	OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_ERROR_IN_NEXTUPDATE_FIELD);
	ret = 0;
	} else {
	t_tmp = t_now - nsec;
	if (X509_cmp_time(nextupd, &t_tmp) < 0) {
	OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY, OCSP_R_STATUS_EXPIRED);
	ret = 0;
	}
	}

	/* Also don't allow nextUpdate to precede thisUpdate */
	if (ASN1_STRING_cmp(nextupd, thisupd) < 0) {
	OCSPerr(OCSP_F_OCSP_CHECK_VALIDITY,
	OCSP_R_NEXTUPDATE_BEFORE_THISUPDATE);
	ret = 0;
	}

	return ret;
	}