/*

 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")

 *

 * SPDX-License-Identifier: MPL-2.0

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, you can obtain one at https://mozilla.org/MPL/2.0/.

 *

 * See the COPYRIGHT file distributed with this work for additional

 * information regarding copyright ownership.

 */

/*! \file */

#include <stddef.h>

#include <string.h>

#include <isc/util.h>

#include <dns/name.h>

#include <dns/nsec3.h>

#include <dns/rdata.h>

#include <dns/rdatalist.h>

#include <dns/rdataset.h>

static dns_rdatasetmethods_t methods = {

  .disassociate = dns_rdatalist_disassociate,

  .first = dns__rdatalist_first,

  .next = dns__rdatalist_next,

  .current = dns__rdatalist_current,

  .clone = dns__rdatalist_clone,

  .count = dns__rdatalist_count,

  .addnoqname = dns__rdatalist_addnoqname,

  .getnoqname = dns__rdatalist_getnoqname,

  .setownercase = dns__rdatalist_setownercase,

  .getownercase = dns__rdatalist_getownercase,

};

void

dns_rdatalist_init(dns_rdatalist_t *rdatalist) {

  REQUIRE(rdatalist != NULL);

  /*

   * Initialize rdatalist.

   */

  *rdatalist = (dns_rdatalist_t){

    .rdata = ISC_LIST_INITIALIZER,

    .link = ISC_LINK_INITIALIZER,

  };

  memset(rdatalist->upper, 0xeb, sizeof(rdatalist->upper));

  /*

   * Clear upper set bit.

   */

  rdatalist->upper[0] &= ~0x01;

}

void

dns_rdatalist_tordataset(dns_rdatalist_t *rdatalist, dns_rdataset_t *rdataset) {

  /*

   * Make 'rdataset' refer to the rdata in 'rdatalist'.

   */

  REQUIRE(rdatalist != NULL);

  REQUIRE(DNS_RDATASET_VALID(rdataset));

  REQUIRE(!dns_rdataset_isassociated(rdataset));

  /* Check if dns_rdatalist_init has was called. */

  REQUIRE(rdatalist->upper[0] == 0xea);

  *rdataset = (dns_rdataset_t){

    .methods = &methods,

    .rdclass = rdatalist->rdclass,

    .type = rdatalist->type,

    .covers = rdatalist->covers,

    .ttl = rdatalist->ttl,

    .rdlist.list = rdatalist,

    .link = rdataset->link,

    .attributes = rdataset->attributes,

    .magic = rdataset->magic,

  };

}

void

dns_rdatalist_fromrdataset(dns_rdataset_t *rdataset,

         dns_rdatalist_t **rdatalist) {

  REQUIRE(rdatalist != NULL && rdataset != NULL);

  REQUIRE(rdataset->methods == &methods);

  *rdatalist = rdataset->rdlist.list;

}

void

dns_rdatalist_disassociate(dns_rdataset_t *rdataset DNS__DB_FLARG) {

  UNUSED(rdataset);

}

isc_result_t

dns__rdatalist_first(dns_rdataset_t *rdataset) {

  dns_rdatalist_t *rdatalist = NULL;

  rdatalist = rdataset->rdlist.list;

  rdataset->rdlist.iter = ISC_LIST_HEAD(rdatalist->rdata);

  if (rdataset->rdlist.iter == NULL) {

    return ISC_R_NOMORE;

  }

  return ISC_R_SUCCESS;

}

isc_result_t

dns__rdatalist_next(dns_rdataset_t *rdataset) {

  dns_rdata_t *rdata;

  rdata = rdataset->rdlist.iter;

  if (rdata == NULL) {

    return ISC_R_NOMORE;

  }

  rdataset->rdlist.iter = ISC_LIST_NEXT(rdata, link);

  if (rdataset->rdlist.iter == NULL) {

    return ISC_R_NOMORE;

  }

  return ISC_R_SUCCESS;

}

void

dns__rdatalist_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) {

  dns_rdata_t *list_rdata;

  list_rdata = rdataset->rdlist.iter;

  INSIST(list_rdata != NULL);

  dns_rdata_clone(list_rdata, rdata);

}

void

dns__rdatalist_clone(const dns_rdataset_t *source,

         dns_rdataset_t *target DNS__DB_FLARG) {

  REQUIRE(source != NULL);

  REQUIRE(target != NULL);

  *target = *source;

  target->rdlist.iter = NULL;

}

unsigned int

dns__rdatalist_count(dns_rdataset_t *rdataset) {

  dns_rdatalist_t *rdatalist = NULL;

  unsigned int count;

  REQUIRE(rdataset != NULL);

  rdatalist = rdataset->rdlist.list;

  count = 0;

  ISC_LIST_FOREACH(rdatalist->rdata, rdata, link) {

    count++;

  }

  return count;

}

isc_result_t

dns__rdatalist_addnoqname(dns_rdataset_t *rdataset, dns_name_t *name) {

  dns_rdataset_t *neg = NULL;

  dns_rdataset_t *negsig = NULL;

  dns_ttl_t ttl;

  REQUIRE(rdataset != NULL);

  ISC_LIST_FOREACH(name->list, rdset, link) {

    if (rdset->rdclass != rdataset->rdclass ||

        !dns_rdatatype_isnsec(rdset->type))

    {

      continue;

    }

    ISC_LIST_FOREACH(name->list, sigset, link) {

      if (sigset->type == dns_rdatatype_rrsig &&

          sigset->covers == rdset->type)

      {

        neg = rdset;

        negsig = sigset;

        break;

      }

    }

  }

  if (neg == NULL || negsig == NULL) {

    return ISC_R_NOTFOUND;

  }

  /*

   * Minimise ttl.

   */

  ttl = rdataset->ttl;

  if (neg->ttl < ttl) {

    ttl = neg->ttl;

  }

  if (negsig->ttl < ttl) {

    ttl = negsig->ttl;

  }

  rdataset->ttl = neg->ttl = negsig->ttl = ttl;

  rdataset->attributes.noqname = true;

  rdataset->rdlist.noqname = name;

  return ISC_R_SUCCESS;

}

isc_result_t

dns__rdatalist_getnoqname(dns_rdataset_t *rdataset, dns_name_t *name,

        dns_rdataset_t *neg,

        dns_rdataset_t *negsig DNS__DB_FLARG) {

  dns_rdataclass_t rdclass;

  dns_rdataset_t *tneg = NULL;

  dns_rdataset_t *tnegsig = NULL;

  dns_name_t *noqname = NULL;

  REQUIRE(rdataset != NULL);

  REQUIRE(rdataset->attributes.noqname);

  rdclass = rdataset->rdclass;

  noqname = rdataset->rdlist.noqname;

  (void)dns_name_dynamic(noqname); /* Sanity Check. */

  ISC_LIST_FOREACH(noqname->list, rdset, link) {

    if (rdset->rdclass != rdclass) {

      continue;

    }

    if (dns_rdatatype_isnsec(rdset->type)) {

      tneg = rdset;

    }

  }

  if (tneg == NULL) {

    return ISC_R_NOTFOUND;

  }

  ISC_LIST_FOREACH(noqname->list, rdset, link) {

    if (rdset->type == dns_rdatatype_rrsig &&

        rdset->covers == tneg->type)

    {

      tnegsig = rdset;

    }

  }

  if (tnegsig == NULL) {

    return ISC_R_NOTFOUND;

  }

  dns_name_clone(noqname, name);

  dns_rdataset_clone(tneg, neg);

  dns_rdataset_clone(tnegsig, negsig);

  return ISC_R_SUCCESS;

}

void

dns__rdatalist_setownercase(dns_rdataset_t *rdataset, const dns_name_t *name) {

  dns_rdatalist_t *rdatalist;

  unsigned int i;

  /*

   * We do not need to worry about label lengths as they are all

   * less than or equal to 63.

   */

  rdatalist = rdataset->rdlist.list;

  memset(rdatalist->upper, 0, sizeof(rdatalist->upper));

  for (i = 1; i < name->length; i++) {

    if (name->ndata[i] >= 0x41 && name->ndata[i] <= 0x5a) {

      rdatalist->upper[i / 8] |= 1 << (i % 8);

    }

  }

  /*

   * Record that upper has been set.

   */

  rdatalist->upper[0] |= 0x01;

}

void

dns__rdatalist_getownercase(const dns_rdataset_t *rdataset, dns_name_t *name) {

  dns_rdatalist_t *rdatalist;

  unsigned int i;

  rdatalist = rdataset->rdlist.list;

  if ((rdatalist->upper[0] & 0x01) == 0) {

    return;

  }

  for (i = 0; i < name->length; i++) {

    /*

     * Set the case bit if it does not match the recorded bit.

     */

    if (name->ndata[i] >= 0x61 && name->ndata[i] <= 0x7a &&

        (rdatalist->upper[i / 8] & (1 << (i % 8))) != 0)

    {

      name->ndata[i] &= ~0x20; /* clear the lower case bit */

    } else if (name->ndata[i] >= 0x41 && name->ndata[i] <= 0x5a &&

         (rdatalist->upper[i / 8] & (1 << (i % 8))) == 0)

    {

      name->ndata[i] |= 0x20; /* set the lower case bit */

    }

  }

}