/*

 * 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.

 */

/*

 * Copyright (C) 2004  Nominet, Ltd.

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND NOMINET DISCLAIMS ALL WARRANTIES WITH

 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY

 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,

 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM

 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE

 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR

 * PERFORMANCE OF THIS SOFTWARE.

 */

/* RFC 5155 */

#ifndef RDATA_GENERIC_NSEC3_50_C

#define RDATA_GENERIC_NSEC3_50_C

#include <isc/base32.h>

#include <isc/iterated_hash.h>

#include <dns/nsec3.h>

#define RRTYPE_NSEC3_ATTRIBUTES DNS_RDATATYPEATTR_DNSSEC

static isc_result_t

fromtext_nsec3(ARGS_FROMTEXT) {

  isc_token_t token;

  unsigned int flags;

  unsigned char hashalg;

  isc_buffer_t b;

  unsigned char buf[256];

  REQUIRE(type == dns_rdatatype_nsec3);

  UNUSED(type);

  UNUSED(rdclass);

  UNUSED(callbacks);

  UNUSED(origin);

  UNUSED(options);

  /* Hash. */

  RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,

              false));

  RETTOK(dns_hashalg_fromtext(&hashalg, &token.value.as_textregion));

  RETERR(uint8_tobuffer(hashalg, target));

  /* Flags. */

  RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_number,

              false));

  flags = token.value.as_ulong;

  if (flags > 255U) {

    RETTOK(ISC_R_RANGE);

  }

  RETERR(uint8_tobuffer(flags, target));

  /* Iterations. */

  RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_number,

              false));

  if (token.value.as_ulong > 0xffffU) {

    RETTOK(ISC_R_RANGE);

  }

  RETERR(uint16_tobuffer(token.value.as_ulong, target));

  /* salt */

  RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,

              false));

  if (token.value.as_textregion.length > (255 * 2)) {

    RETTOK(DNS_R_TEXTTOOLONG);

  }

  if (strcmp(DNS_AS_STR(token), "-") == 0) {

    RETERR(uint8_tobuffer(0, target));

  } else {

    RETERR(uint8_tobuffer(strlen(DNS_AS_STR(token)) / 2, target));

    RETERR(isc_hex_decodestring(DNS_AS_STR(token), target));

  }

  /*

   * Next hash a single base32hex word.

   */

  RETERR(isc_lex_getmastertoken(lexer, &token, isc_tokentype_string,

              false));

  isc_buffer_init(&b, buf, sizeof(buf));

  RETTOK(isc_base32hexnp_decodestring(DNS_AS_STR(token), &b));

  switch (hashalg) {

  case dns_hash_sha1:

    if (isc_buffer_usedlength(&b) != ISC_SHA1_DIGESTLENGTH) {

      RETTOK(ISC_R_RANGE);

    }

    break;

  default:

    if (isc_buffer_usedlength(&b) > NSEC3_MAX_HASH_LENGTH) {

      RETTOK(ISC_R_RANGE);

    }

    break;

  }

  RETERR(uint8_tobuffer(isc_buffer_usedlength(&b), target));

  RETERR(mem_tobuffer(target, &buf, isc_buffer_usedlength(&b)));

  return typemap_fromtext(lexer, target, true);

}

static isc_result_t

totext_nsec3(ARGS_TOTEXT) {

  isc_region_t sr;

  unsigned int i, j;

  unsigned char hash;

  unsigned char flags;

  char buf[sizeof("TYPE65535")];

  uint32_t iterations;

  REQUIRE(rdata->type == dns_rdatatype_nsec3);

  REQUIRE(rdata->length != 0);

  dns_rdata_toregion(rdata, &sr);

  /* Hash */

  hash = uint8_fromregion(&sr);

  isc_region_consume(&sr, 1);

  snprintf(buf, sizeof(buf), "%u ", hash);

  RETERR(str_totext(buf, target));

  /* Flags */

  flags = uint8_fromregion(&sr);

  isc_region_consume(&sr, 1);

  snprintf(buf, sizeof(buf), "%u ", flags);

  RETERR(str_totext(buf, target));

  /* Iterations */

  iterations = uint16_fromregion(&sr);

  isc_region_consume(&sr, 2);

  snprintf(buf, sizeof(buf), "%u ", iterations);

  RETERR(str_totext(buf, target));

  /* Salt */

  j = uint8_fromregion(&sr);

  isc_region_consume(&sr, 1);

  INSIST(j <= sr.length);

  if (j != 0) {

    i = sr.length;

    sr.length = j;

    RETERR(isc_hex_totext(&sr, 1, "", target));

    sr.length = i - j;

  } else {

    RETERR(str_totext("-", target));

  }

  if ((tctx->flags & DNS_STYLEFLAG_MULTILINE) != 0) {

    RETERR(str_totext(" (", target));

  }

  RETERR(str_totext(tctx->linebreak, target));

  /* Next hash */

  j = uint8_fromregion(&sr);

  isc_region_consume(&sr, 1);

  INSIST(j <= sr.length);

  i = sr.length;

  sr.length = j;

  RETERR(isc_base32hexnp_totext(&sr, 1, "", target));

  sr.length = i - j;

  /*

   * Don't leave a trailing space when there's no typemap present.

   */

  if (((tctx->flags & DNS_STYLEFLAG_MULTILINE) == 0) && (sr.length > 0)) {

    RETERR(str_totext(" ", target));

  }

  RETERR(typemap_totext(&sr, tctx, target));

  if ((tctx->flags & DNS_STYLEFLAG_MULTILINE) != 0) {

    RETERR(str_totext(" )", target));

  }

  return ISC_R_SUCCESS;

}

static isc_result_t

fromwire_nsec3(ARGS_FROMWIRE) {

  isc_region_t sr, rr;

  unsigned int hash, saltlen, hashlen;

  REQUIRE(type == dns_rdatatype_nsec3);

  UNUSED(type);

  UNUSED(rdclass);

  UNUSED(dctx);

  isc_buffer_activeregion(source, &sr);

  rr = sr;

  /* hash(1), flags(1), iteration(2), saltlen(1) */

  if (sr.length < 5U) {

    RETERR(DNS_R_FORMERR);

  }

  hash = sr.base[0];

  saltlen = sr.base[4];

  isc_region_consume(&sr, 5);

  if (sr.length < saltlen) {

    RETERR(DNS_R_FORMERR);

  }

  isc_region_consume(&sr, saltlen);

  if (sr.length < 1U) {

    RETERR(DNS_R_FORMERR);

  }

  hashlen = sr.base[0];

  isc_region_consume(&sr, 1);

  switch (hash) {

  case dns_hash_sha1:

    if (hashlen != ISC_SHA1_DIGESTLENGTH || sr.length < hashlen) {

      RETERR(DNS_R_FORMERR);

    }

    break;

  default:

    if (hashlen < 1 || hashlen > NSEC3_MAX_HASH_LENGTH ||

        sr.length < hashlen)

    {

      RETERR(DNS_R_FORMERR);

    }

    break;

  }

  isc_region_consume(&sr, hashlen);

  RETERR(typemap_test(&sr, true));

  RETERR(mem_tobuffer(target, rr.base, rr.length));

  isc_buffer_forward(source, rr.length);

  return ISC_R_SUCCESS;

}

static isc_result_t

towire_nsec3(ARGS_TOWIRE) {

  isc_region_t sr;

  REQUIRE(rdata->type == dns_rdatatype_nsec3);

  REQUIRE(rdata->length != 0);

  UNUSED(cctx);

  dns_rdata_toregion(rdata, &sr);

  return mem_tobuffer(target, sr.base, sr.length);

}

static int

compare_nsec3(ARGS_COMPARE) {

  isc_region_t r1;

  isc_region_t r2;

  REQUIRE(rdata1->type == rdata2->type);

  REQUIRE(rdata1->rdclass == rdata2->rdclass);

  REQUIRE(rdata1->type == dns_rdatatype_nsec3);

  REQUIRE(rdata1->length != 0);

  REQUIRE(rdata2->length != 0);

  dns_rdata_toregion(rdata1, &r1);

  dns_rdata_toregion(rdata2, &r2);

  return isc_region_compare(&r1, &r2);

}

static isc_result_t

fromstruct_nsec3(ARGS_FROMSTRUCT) {

  dns_rdata_nsec3_t *nsec3 = source;

  isc_region_t region;

  REQUIRE(type == dns_rdatatype_nsec3);

  REQUIRE(nsec3 != NULL);

  REQUIRE(nsec3->common.rdtype == type);

  REQUIRE(nsec3->common.rdclass == rdclass);

  REQUIRE(nsec3->typebits != NULL || nsec3->len == 0);

  UNUSED(type);

  UNUSED(rdclass);

  RETERR(uint8_tobuffer(nsec3->hash, target));

  RETERR(uint8_tobuffer(nsec3->flags, target));

  RETERR(uint16_tobuffer(nsec3->iterations, target));

  RETERR(uint8_tobuffer(nsec3->salt_length, target));

  RETERR(mem_tobuffer(target, nsec3->salt, nsec3->salt_length));

  RETERR(uint8_tobuffer(nsec3->next_length, target));

  RETERR(mem_tobuffer(target, nsec3->next, nsec3->next_length));

  region.base = nsec3->typebits;

  region.length = nsec3->len;

  RETERR(typemap_test(&region, true));

  return mem_tobuffer(target, nsec3->typebits, nsec3->len);

}

static isc_result_t

tostruct_nsec3(ARGS_TOSTRUCT) {

  isc_region_t region;

  dns_rdata_nsec3_t *nsec3 = target;

  REQUIRE(rdata->type == dns_rdatatype_nsec3);

  REQUIRE(nsec3 != NULL);

  REQUIRE(rdata->length != 0);

  DNS_RDATACOMMON_INIT(nsec3, rdata->type, rdata->rdclass);

  region.base = rdata->data;

  region.length = rdata->length;

  nsec3->hash = uint8_consume_fromregion(&region);

  nsec3->flags = uint8_consume_fromregion(&region);

  nsec3->iterations = uint16_consume_fromregion(&region);

  nsec3->salt_length = uint8_consume_fromregion(&region);

  INSIST(nsec3->salt_length <= region.length);

  nsec3->salt = mem_maybedup(mctx, region.base, nsec3->salt_length);

  isc_region_consume(&region, nsec3->salt_length);

  nsec3->next_length = uint8_consume_fromregion(&region);

  INSIST(nsec3->next_length <= region.length);

  nsec3->next = mem_maybedup(mctx, region.base, nsec3->next_length);

  isc_region_consume(&region, nsec3->next_length);

  nsec3->len = region.length;

  nsec3->typebits = mem_maybedup(mctx, region.base, region.length);

  nsec3->mctx = mctx;

  return ISC_R_SUCCESS;

}

static void

freestruct_nsec3(ARGS_FREESTRUCT) {

  dns_rdata_nsec3_t *nsec3 = source;

  REQUIRE(nsec3 != NULL);

  REQUIRE(nsec3->common.rdtype == dns_rdatatype_nsec3);

  if (nsec3->mctx == NULL) {

    return;

  }

  if (nsec3->salt != NULL) {

    isc_mem_free(nsec3->mctx, nsec3->salt);

  }

  if (nsec3->next != NULL) {

    isc_mem_free(nsec3->mctx, nsec3->next);

  }

  if (nsec3->typebits != NULL) {

    isc_mem_free(nsec3->mctx, nsec3->typebits);

  }

  nsec3->mctx = NULL;

}

static isc_result_t

additionaldata_nsec3(ARGS_ADDLDATA) {

  REQUIRE(rdata->type == dns_rdatatype_nsec3);

  UNUSED(rdata);

  UNUSED(owner);

  UNUSED(add);

  UNUSED(arg);

  return ISC_R_SUCCESS;

}

static isc_result_t

digest_nsec3(ARGS_DIGEST) {

  isc_region_t r;

  REQUIRE(rdata->type == dns_rdatatype_nsec3);

  dns_rdata_toregion(rdata, &r);

  return (digest)(arg, &r);

}

static bool

checkowner_nsec3(ARGS_CHECKOWNER) {

  unsigned char owner[NSEC3_MAX_HASH_LENGTH];

  isc_buffer_t buffer;

  dns_label_t label;

  REQUIRE(type == dns_rdatatype_nsec3);

  UNUSED(type);

  UNUSED(rdclass);

  UNUSED(wildcard);

  /*

   * First label is a base32hex string without padding.

   */

  dns_name_getlabel(name, 0, &label);

  isc_region_consume(&label, 1);

  isc_buffer_init(&buffer, owner, sizeof(owner));

  if (isc_base32hexnp_decoderegion(&label, &buffer) == ISC_R_SUCCESS) {

    return true;

  }

  return false;

}

static bool

checknames_nsec3(ARGS_CHECKNAMES) {

  REQUIRE(rdata->type == dns_rdatatype_nsec3);

  UNUSED(rdata);

  UNUSED(owner);

  UNUSED(bad);

  return true;

}

static int

casecompare_nsec3(ARGS_COMPARE) {

  return compare_nsec3(rdata1, rdata2);

}

#endif /* RDATA_GENERIC_NSEC3_50_C */