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
ares_parse_soa_reply(const unsigned char * abuf,int alen_int,struct ares_soa_reply ** soa_out)30 int ares_parse_soa_reply(const unsigned char *abuf, int alen_int,
31 struct ares_soa_reply **soa_out)
32 {
33 ares_status_t status;
34 size_t alen;
35 struct ares_soa_reply *soa = NULL;
36 ares_dns_record_t *dnsrec = NULL;
37 size_t i;
38
39 *soa_out = NULL;
40
41 if (alen_int < 0) {
42 return ARES_EBADRESP;
43 }
44
45 alen = (size_t)alen_int;
46
47 status = ares_dns_parse(abuf, alen, 0, &dnsrec);
48 if (status != ARES_SUCCESS) {
49 goto done;
50 }
51
52 if (ares_dns_record_rr_cnt(dnsrec, ARES_SECTION_ANSWER) == 0) {
53 status = ARES_EBADRESP; /* ENODATA might make more sense */
54 goto done;
55 }
56
57 for (i = 0; i < ares_dns_record_rr_cnt(dnsrec, ARES_SECTION_ANSWER); i++) {
58 const ares_dns_rr_t *rr =
59 ares_dns_record_rr_get(dnsrec, ARES_SECTION_ANSWER, i);
60
61 if (rr == NULL) {
62 /* Shouldn't be possible */
63 status = ARES_EBADRESP; /* LCOV_EXCL_LINE: DefensiveCoding */
64 goto done; /* LCOV_EXCL_LINE: DefensiveCoding */
65 }
66
67 if (ares_dns_rr_get_class(rr) != ARES_CLASS_IN ||
68 ares_dns_rr_get_type(rr) != ARES_REC_TYPE_SOA) {
69 continue;
70 }
71
72 /* allocate result struct */
73 soa = ares_malloc_data(ARES_DATATYPE_SOA_REPLY);
74 if (soa == NULL) {
75 status = ARES_ENOMEM; /* LCOV_EXCL_LINE: OutOfMemory */
76 goto done; /* LCOV_EXCL_LINE: OutOfMemory */
77 }
78
79 soa->serial = ares_dns_rr_get_u32(rr, ARES_RR_SOA_SERIAL);
80 soa->refresh = ares_dns_rr_get_u32(rr, ARES_RR_SOA_REFRESH);
81 soa->retry = ares_dns_rr_get_u32(rr, ARES_RR_SOA_RETRY);
82 soa->expire = ares_dns_rr_get_u32(rr, ARES_RR_SOA_EXPIRE);
83 soa->minttl = ares_dns_rr_get_u32(rr, ARES_RR_SOA_MINIMUM);
84 soa->nsname = ares_strdup(ares_dns_rr_get_str(rr, ARES_RR_SOA_MNAME));
85 if (soa->nsname == NULL) {
86 status = ARES_ENOMEM; /* LCOV_EXCL_LINE: OutOfMemory */
87 goto done; /* LCOV_EXCL_LINE: OutOfMemory */
88 }
89 soa->hostmaster = ares_strdup(ares_dns_rr_get_str(rr, ARES_RR_SOA_RNAME));
90 if (soa->hostmaster == NULL) {
91 status = ARES_ENOMEM; /* LCOV_EXCL_LINE: OutOfMemory */
92 goto done; /* LCOV_EXCL_LINE: OutOfMemory */
93 }
94 break;
95 }
96
97 if (soa == NULL) {
98 status = ARES_EBADRESP;
99 }
100
101 done:
102 /* clean up on error */
103 if (status != ARES_SUCCESS) {
104 ares_free_data(soa);
105 /* Compatibility */
106 if (status == ARES_EBADNAME) {
107 status = ARES_EBADRESP;
108 }
109 } else {
110 /* everything looks fine, return the data */
111 *soa_out = soa;
112 }
113 ares_dns_record_destroy(dnsrec);
114 return (int)status;
115 }
116