ocsp_cl.c

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/* ocsp_cl.c */
/* Written by Tom Titchener <[email protected]> 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
 *    [email protected].
 *
 * 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
 * ([email protected]).  This product includes software written by Tim
 * Hudson ([email protected]).
 *
 */

#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;
    OCSP_SIGNATURE *sig;
    X509 *x;

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

    if (!(req->optionalSignature = sig = 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;
    }