/* MIT License

 *

 * Copyright (c) 2023 Brad House

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice (including the next

 * paragraph) shall be included in all copies or substantial portions of the

 * Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

 * SOFTWARE.

 *

 * SPDX-License-Identifier: MIT

 */

#include "ares_setup.h"

#include "ares.h"

#include "ares_data.h"

#include "ares_private.h"

static int ares__parse_txt_reply(const unsigned char *abuf, size_t alen,

                                 ares_bool_t ex, void **txt_out)

{

  ares_status_t        status;

  struct ares_txt_ext *txt_head = NULL;

  struct ares_txt_ext *txt_last = NULL;

  struct ares_txt_ext *txt_curr;

  ares_dns_record_t   *dnsrec = NULL;

  size_t               i;

  *txt_out = NULL;

  status = ares_dns_parse(abuf, alen, 0, &dnsrec);

  if (status != ARES_SUCCESS) {

    goto done;

  }

  if (ares_dns_record_rr_cnt(dnsrec, ARES_SECTION_ANSWER) == 0) {

    status = ARES_ENODATA;

    goto done;

  }

  for (i = 0; i < ares_dns_record_rr_cnt(dnsrec, ARES_SECTION_ANSWER); i++) {

    const ares_dns_rr_t *rr =

      ares_dns_record_rr_get(dnsrec, ARES_SECTION_ANSWER, i);

    const unsigned char *ptr;

    size_t               ptr_len;

    if (rr == NULL) {

      /* Shouldn't be possible */

      status = ARES_EBADRESP;

      goto done;

    }

    /* XXX: Why Chaos? */

    if ((ares_dns_rr_get_class(rr) != ARES_CLASS_IN &&

         ares_dns_rr_get_class(rr) != ARES_CLASS_CHAOS) ||

        ares_dns_rr_get_type(rr) != ARES_REC_TYPE_TXT) {

      continue;

    }

    /* Allocate storage for this TXT answer appending it to the list */

    txt_curr =

      ares_malloc_data(ex ? ARES_DATATYPE_TXT_EXT : ARES_DATATYPE_TXT_REPLY);

    if (txt_curr == NULL) {

      status = ARES_ENOMEM;

      goto done;

    }

    /* Link in the record */

    if (txt_last) {

      txt_last->next = txt_curr;

    } else {

      txt_head = txt_curr;

    }

    txt_last = txt_curr;

    /* These days, records are joined, always tag as start */

    if (ex) {

      txt_curr->record_start = 1;

    }

    ptr = ares_dns_rr_get_bin(rr, ARES_RR_TXT_DATA, &ptr_len);

    txt_curr->txt = ares_malloc(ptr_len + 1);

    if (txt_curr->txt == NULL) {

      status = ARES_ENOMEM;

      goto done;

    }

    memcpy(txt_curr->txt, ptr, ptr_len);

    txt_curr->txt[ptr_len] = 0;

    txt_curr->length       = ptr_len;

  }

done:

  /* clean up on error */

  if (status != ARES_SUCCESS) {

    if (txt_head) {

      ares_free_data(txt_head);

    }

  } else {

    /* everything looks fine, return the data */

    *txt_out = txt_head;

  }

  ares_dns_record_destroy(dnsrec);

  return (int)status;

}

int ares_parse_txt_reply(const unsigned char *abuf, int alen,

                         struct ares_txt_reply **txt_out)

{

  if (alen < 0) {

    return ARES_EBADRESP;

  }

  return ares__parse_txt_reply(abuf, (size_t)alen, ARES_FALSE,

                               (void **)txt_out);

}

int ares_parse_txt_reply_ext(const unsigned char *abuf, int alen,

                             struct ares_txt_ext **txt_out)

{

  if (alen < 0) {

    return ARES_EBADRESP;

  }

  return ares__parse_txt_reply(abuf, (size_t)alen, ARES_TRUE, (void **)txt_out);

}