quickjs-tart

quickjs-based runtime for wallet-core logic
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ares_parse_txt_reply.c (4526B)

      1 /* MIT License
      2  *
      3  * Copyright (c) 2023 Brad House
      4  *
      5  * Permission is hereby granted, free of charge, to any person obtaining a copy
      6  * of this software and associated documentation files (the "Software"), to deal
      7  * in the Software without restriction, including without limitation the rights
      8  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
      9  * copies of the Software, and to permit persons to whom the Software is
     10  * furnished to do so, subject to the following conditions:
     11  *
     12  * The above copyright notice and this permission notice (including the next
     13  * paragraph) shall be included in all copies or substantial portions of the
     14  * Software.
     15  *
     16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
     19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
     20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
     21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
     22  * SOFTWARE.
     23  *
     24  * SPDX-License-Identifier: MIT
     25  */
     26 
     27 #include "ares_private.h"
     28 #include "ares_data.h"
     29 
     30 static int ares_parse_txt_reply_int(const unsigned char *abuf, size_t alen,
     31                                     ares_bool_t ex, void **txt_out)
     32 {
     33   ares_status_t        status;
     34   struct ares_txt_ext *txt_head = NULL;
     35   struct ares_txt_ext *txt_last = NULL;
     36   struct ares_txt_ext *txt_curr;
     37   ares_dns_record_t   *dnsrec = NULL;
     38   size_t               i;
     39 
     40   *txt_out = NULL;
     41 
     42   status = ares_dns_parse(abuf, alen, 0, &dnsrec);
     43   if (status != ARES_SUCCESS) {
     44     goto done;
     45   }
     46 
     47   if (ares_dns_record_rr_cnt(dnsrec, ARES_SECTION_ANSWER) == 0) {
     48     status = ARES_ENODATA;
     49     goto done;
     50   }
     51 
     52   for (i = 0; i < ares_dns_record_rr_cnt(dnsrec, ARES_SECTION_ANSWER); i++) {
     53     const ares_dns_rr_t *rr =
     54       ares_dns_record_rr_get(dnsrec, ARES_SECTION_ANSWER, i);
     55     size_t j;
     56     size_t cnt;
     57 
     58 
     59     if (rr == NULL) {
     60       /* Shouldn't be possible */
     61       status = ARES_EBADRESP; /* LCOV_EXCL_LINE: DefensiveCoding */
     62       goto done;              /* LCOV_EXCL_LINE: DefensiveCoding */
     63     }
     64 
     65     /* XXX: Why Chaos? */
     66     if ((ares_dns_rr_get_class(rr) != ARES_CLASS_IN &&
     67          ares_dns_rr_get_class(rr) != ARES_CLASS_CHAOS) ||
     68         ares_dns_rr_get_type(rr) != ARES_REC_TYPE_TXT) {
     69       continue;
     70     }
     71 
     72     cnt = ares_dns_rr_get_abin_cnt(rr, ARES_RR_TXT_DATA);
     73 
     74     for (j = 0; j < cnt; j++) {
     75       const unsigned char *ptr;
     76       size_t               ptr_len;
     77 
     78       /* Allocate storage for this TXT answer appending it to the list */
     79       txt_curr =
     80         ares_malloc_data(ex ? ARES_DATATYPE_TXT_EXT : ARES_DATATYPE_TXT_REPLY);
     81       if (txt_curr == NULL) {
     82         status = ARES_ENOMEM; /* LCOV_EXCL_LINE: OutOfMemory */
     83         goto done;            /* LCOV_EXCL_LINE: OutOfMemory */
     84       }
     85 
     86       /* Link in the record */
     87       if (txt_last) {
     88         txt_last->next = txt_curr;
     89       } else {
     90         txt_head = txt_curr;
     91       }
     92       txt_last = txt_curr;
     93 
     94       /* Tag start on first for each TXT record */
     95       if (ex && j == 0) {
     96         txt_curr->record_start = 1;
     97       }
     98 
     99       ptr = ares_dns_rr_get_abin(rr, ARES_RR_TXT_DATA, j, &ptr_len);
    100 
    101       txt_curr->txt = ares_malloc(ptr_len + 1);
    102       if (txt_curr->txt == NULL) {
    103         status = ARES_ENOMEM; /* LCOV_EXCL_LINE: OutOfMemory */
    104         goto done;            /* LCOV_EXCL_LINE: OutOfMemory */
    105       }
    106       memcpy(txt_curr->txt, ptr, ptr_len);
    107       txt_curr->txt[ptr_len] = 0;
    108       txt_curr->length       = ptr_len;
    109     }
    110   }
    111 
    112 done:
    113   /* clean up on error */
    114   if (status != ARES_SUCCESS) {
    115     if (txt_head) {
    116       ares_free_data(txt_head);
    117     }
    118   } else {
    119     /* everything looks fine, return the data */
    120     *txt_out = txt_head;
    121   }
    122   ares_dns_record_destroy(dnsrec);
    123   return (int)status;
    124 }
    125 
    126 int ares_parse_txt_reply(const unsigned char *abuf, int alen,
    127                          struct ares_txt_reply **txt_out)
    128 {
    129   if (alen < 0) {
    130     return ARES_EBADRESP;
    131   }
    132   return ares_parse_txt_reply_int(abuf, (size_t)alen, ARES_FALSE,
    133                                   (void **)txt_out);
    134 }
    135 
    136 int ares_parse_txt_reply_ext(const unsigned char *abuf, int alen,
    137                              struct ares_txt_ext **txt_out)
    138 {
    139   if (alen < 0) {
    140     return ARES_EBADRESP;
    141   }
    142   return ares_parse_txt_reply_int(abuf, (size_t)alen, ARES_TRUE,
    143                                   (void **)txt_out);
    144 }