/*

 * Copyright 2001-2021 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 <stdio.h>

#include <time.h>

#include "internal/cryptlib.h"

#include <openssl/asn1.h>

#include <openssl/objects.h>

#include <openssl/x509.h>

#include <openssl/pem.h>

#include <openssl/x509v3.h>

#include <openssl/ocsp.h>

#include "ocsp_local.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()) == NULL)

        return NULL;

    OCSP_CERTID_free(one->reqCert);

    one->reqCert = cid;

    if (req && !sk_OCSP_ONEREQ_push(req->tbsRequest.requestList, one)) {

        one->reqCert = NULL; /* do not free on error */

        OCSP_ONEREQ_free(one);

        return NULL;

    }

    return one;

}

/* Set requestorName from an X509_NAME structure */

int OCSP_request_set1_name(OCSP_REQUEST *req, const X509_NAME *nm)

{

    GENERAL_NAME *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;

    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)

{

    if (req->optionalSignature == NULL

            && (req->optionalSignature = OCSP_SIGNATURE_new()) == NULL)

        return 0;

    if (cert == NULL)

        return 1;

    return ossl_x509_add_cert_new(&req->optionalSignature->certs, cert,

                                  X509_ADD_FLAG_UP_REF);

}

/*

 * Sign an OCSP request set the requestorName to the subject 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)

{

    if (!OCSP_request_set1_name(req, X509_get_subject_name(signer)))

        goto err;

    if ((req->optionalSignature = OCSP_SIGNATURE_new()) == NULL)

        goto err;

    if (key != NULL) {

        if (!X509_check_private_key(signer, key)) {

            ERR_raise(ERR_LIB_OCSP,

                      OCSP_R_PRIVATE_KEY_DOES_NOT_MATCH_CERTIFICATE);

            goto err;

        }

        if (!OCSP_REQUEST_sign(req, key, dgst, signer->libctx, signer->propq))

            goto err;

    }

    if ((flags & OCSP_NOCERTS) == 0) {

        if (!OCSP_request_add1_cert(req, signer)

            || !X509_add_certs(req->optionalSignature->certs, certs,

                               X509_ADD_FLAG_UP_REF))

            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 = resp->responseBytes;

    if (rb == NULL) {

        ERR_raise(ERR_LIB_OCSP, OCSP_R_NO_RESPONSE_DATA);

        return NULL;

    }

    if (OBJ_obj2nid(rb->responseType) != NID_id_pkix_OCSP_basic) {

        ERR_raise(ERR_LIB_OCSP, OCSP_R_NOT_BASIC_RESPONSE);

        return NULL;

    }

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

}

const ASN1_OCTET_STRING *OCSP_resp_get0_signature(const OCSP_BASICRESP *bs)

{

    return bs->signature;

}

const X509_ALGOR *OCSP_resp_get0_tbs_sigalg(const OCSP_BASICRESP *bs)

{

    return &bs->signatureAlgorithm;

}

const OCSP_RESPDATA *OCSP_resp_get0_respdata(const OCSP_BASICRESP *bs)

{

    return &bs->tbsResponseData;

}

/* Return number of OCSP_SINGLERESP responses present in a basic response */

int OCSP_resp_count(OCSP_BASICRESP *bs)

{

    if (bs == NULL)

        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 == NULL)

        return NULL;

    return sk_OCSP_SINGLERESP_value(bs->tbsResponseData.responses, idx);

}

const ASN1_GENERALIZEDTIME *OCSP_resp_get0_produced_at(const OCSP_BASICRESP *bs)

{

    return bs->tbsResponseData.producedAt;

}

const STACK_OF(X509) *OCSP_resp_get0_certs(const OCSP_BASICRESP *bs)

{

    return bs->certs;

}

int OCSP_resp_get0_id(const OCSP_BASICRESP *bs,

                      const ASN1_OCTET_STRING **pid,

                      const X509_NAME **pname)

{

    const OCSP_RESPID *rid = &bs->tbsResponseData.responderId;

    if (rid->type == V_OCSP_RESPID_NAME) {

        *pname = rid->value.byName;

        *pid = NULL;

    } else if (rid->type == V_OCSP_RESPID_KEY) {

        *pid = rid->value.byKey;

        *pname = NULL;

    } else {

        return 0;

    }

    return 1;

}

int OCSP_resp_get1_id(const OCSP_BASICRESP *bs,

                      ASN1_OCTET_STRING **pid,

                      X509_NAME **pname)

{

    const OCSP_RESPID *rid = &bs->tbsResponseData.responderId;

    if (rid->type == V_OCSP_RESPID_NAME) {

        *pname = X509_NAME_dup(rid->value.byName);

        *pid = NULL;

    } else if (rid->type == V_OCSP_RESPID_KEY) {

        *pid = ASN1_OCTET_STRING_dup(rid->value.byKey);

        *pname = NULL;

    } else {

        return 0;

    }

    if (*pname == NULL && *pid == NULL)

        return 0;

    return 1;

}

/* 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 == NULL)

        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 == NULL)

        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 != NULL)

        *thisupd = single->thisUpdate;

    if (nextupd != NULL)

        *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_resp_find(bs, id, -1);

    OCSP_SINGLERESP *single;

    /* 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 != NULL)

        *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 won't 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)) {

        ERR_raise(ERR_LIB_OCSP, OCSP_R_ERROR_IN_THISUPDATE_FIELD);

        ret = 0;

    } else {

        t_tmp = t_now + nsec;

        if (X509_cmp_time(thisupd, &t_tmp) > 0) {

            ERR_raise(ERR_LIB_OCSP, 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) {

                ERR_raise(ERR_LIB_OCSP, OCSP_R_STATUS_TOO_OLD);

                ret = 0;

            }

        }

    }

    if (nextupd == NULL)

        return ret;

    /* Check nextUpdate is valid and not more than nsec in the past */

    if (!ASN1_GENERALIZEDTIME_check(nextupd)) {

        ERR_raise(ERR_LIB_OCSP, OCSP_R_ERROR_IN_NEXTUPDATE_FIELD);

        ret = 0;

    } else {

        t_tmp = t_now - nsec;

        if (X509_cmp_time(nextupd, &t_tmp) < 0) {

            ERR_raise(ERR_LIB_OCSP, OCSP_R_STATUS_EXPIRED);

            ret = 0;

        }

    }

    /* Also don't allow nextUpdate to precede thisUpdate */

    if (ASN1_STRING_cmp(nextupd, thisupd) < 0) {

        ERR_raise(ERR_LIB_OCSP, OCSP_R_NEXTUPDATE_BEFORE_THISUPDATE);

        ret = 0;

    }

    return ret;

}

const OCSP_CERTID *OCSP_SINGLERESP_get0_id(const OCSP_SINGLERESP *single)

{

    return single->certId;

}