/*

 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project

 * 1999.

 */

/* ====================================================================

 * Copyright (c) 1999 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

 *    licensing@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 <string.h>

#include <openssl/asn1.h>

#include <openssl/asn1t.h>

#include <openssl/conf.h>

#include <openssl/err.h>

#include <openssl/mem.h>

#include <openssl/obj.h>

#include <openssl/x509v3.h>

#include "internal.h"

static STACK_OF(CONF_VALUE) *i2v_AUTHORITY_KEYID(

    const X509V3_EXT_METHOD *method, void *ext, STACK_OF(CONF_VALUE) *extlist);

static void *v2i_AUTHORITY_KEYID(const X509V3_EXT_METHOD *method,

                                 const X509V3_CTX *ctx,

                                 const STACK_OF(CONF_VALUE) *values);

const X509V3_EXT_METHOD v3_akey_id = {

    NID_authority_key_identifier,

    X509V3_EXT_MULTILINE,

    ASN1_ITEM_ref(AUTHORITY_KEYID),

    0,

    0,

    0,

    0,

    0,

    0,

    i2v_AUTHORITY_KEYID,

    v2i_AUTHORITY_KEYID,

    0,

    0,

    NULL,

};

static STACK_OF(CONF_VALUE) *i2v_AUTHORITY_KEYID(

    const X509V3_EXT_METHOD *method, void *ext, STACK_OF(CONF_VALUE) *extlist) {

  const AUTHORITY_KEYID *akeyid = ext;

  int extlist_was_null = extlist == NULL;

  if (akeyid->keyid) {

    char *tmp = x509v3_bytes_to_hex(akeyid->keyid->data, akeyid->keyid->length);

    int ok = tmp != NULL && X509V3_add_value("keyid", tmp, &extlist);

    OPENSSL_free(tmp);

    if (!ok) {

      goto err;

    }

  }

  if (akeyid->issuer) {

    STACK_OF(CONF_VALUE) *tmpextlist =

        i2v_GENERAL_NAMES(NULL, akeyid->issuer, extlist);

    if (tmpextlist == NULL) {

      goto err;

    }

    extlist = tmpextlist;

  }

  if (akeyid->serial) {

    if (!X509V3_add_value_int("serial", akeyid->serial, &extlist)) {

      goto err;

    }

  }

  return extlist;

err:

  if (extlist_was_null) {

    sk_CONF_VALUE_pop_free(extlist, X509V3_conf_free);

  }

  return NULL;

}

// Currently two options: keyid: use the issuers subject keyid, the value

// 'always' means its is an error if the issuer certificate doesn't have a

// key id. issuer: use the issuers cert issuer and serial number. The default

// is to only use this if keyid is not present. With the option 'always' this

// is always included.

static void *v2i_AUTHORITY_KEYID(const X509V3_EXT_METHOD *method,

                                 const X509V3_CTX *ctx,

                                 const STACK_OF(CONF_VALUE) *values) {

  char keyid = 0, issuer = 0;

  int j;

  ASN1_OCTET_STRING *ikeyid = NULL;

  X509_NAME *isname = NULL;

  GENERAL_NAMES *gens = NULL;

  GENERAL_NAME *gen = NULL;

  ASN1_INTEGER *serial = NULL;

  const X509 *cert;

  AUTHORITY_KEYID *akeyid;

  for (size_t i = 0; i < sk_CONF_VALUE_num(values); i++) {

    const CONF_VALUE *cnf = sk_CONF_VALUE_value(values, i);

    if (!strcmp(cnf->name, "keyid")) {

      keyid = 1;

      if (cnf->value && !strcmp(cnf->value, "always")) {

        keyid = 2;

      }

    } else if (!strcmp(cnf->name, "issuer")) {

      issuer = 1;

      if (cnf->value && !strcmp(cnf->value, "always")) {

        issuer = 2;

      }

    } else {

      OPENSSL_PUT_ERROR(X509V3, X509V3_R_UNKNOWN_OPTION);

      ERR_add_error_data(2, "name=", cnf->name);

      return NULL;

    }

  }

  if (!ctx || !ctx->issuer_cert) {

    if (ctx && (ctx->flags == X509V3_CTX_TEST)) {

      return AUTHORITY_KEYID_new();

    }

    OPENSSL_PUT_ERROR(X509V3, X509V3_R_NO_ISSUER_CERTIFICATE);

    return NULL;

  }

  cert = ctx->issuer_cert;

  if (keyid) {

    j = X509_get_ext_by_NID(cert, NID_subject_key_identifier, -1);

    const X509_EXTENSION *ext;

    if ((j >= 0) && (ext = X509_get_ext(cert, j))) {

      ikeyid = X509V3_EXT_d2i(ext);

    }

    if (keyid == 2 && !ikeyid) {

      OPENSSL_PUT_ERROR(X509V3, X509V3_R_UNABLE_TO_GET_ISSUER_KEYID);

      return NULL;

    }

  }

  if ((issuer && !ikeyid) || (issuer == 2)) {

    isname = X509_NAME_dup(X509_get_issuer_name(cert));

    serial = ASN1_INTEGER_dup(X509_get0_serialNumber(cert));

    if (!isname || !serial) {

      OPENSSL_PUT_ERROR(X509V3, X509V3_R_UNABLE_TO_GET_ISSUER_DETAILS);

      goto err;

    }

  }

  if (!(akeyid = AUTHORITY_KEYID_new())) {

    goto err;

  }

  if (isname) {

    if (!(gens = sk_GENERAL_NAME_new_null()) || !(gen = GENERAL_NAME_new()) ||

        !sk_GENERAL_NAME_push(gens, gen)) {

      goto err;

    }

    gen->type = GEN_DIRNAME;

    gen->d.dirn = isname;

  }

  akeyid->issuer = gens;

  akeyid->serial = serial;

  akeyid->keyid = ikeyid;

  return akeyid;

err:

  X509_NAME_free(isname);

  ASN1_INTEGER_free(serial);

  ASN1_OCTET_STRING_free(ikeyid);

  return NULL;

}