1 /* MIT License
2 *
3 * Copyright (c) 2009 Daniel Stenberg
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
28 #include "ares_setup.h"
29
30 #include <stddef.h>
31
32 #include "ares.h"
33 #include "ares_data.h"
34 #include "ares_private.h"
35
36 /*
37 ** ares_free_data() - c-ares external API function.
38 **
39 ** This function must be used by the application to free data memory that
40 ** has been internally allocated by some c-ares function and for which a
41 ** pointer has already been returned to the calling application. The list
42 ** of c-ares functions returning pointers that must be free'ed using this
43 ** function is:
44 **
45 ** ares_get_servers()
46 ** ares_parse_srv_reply()
47 ** ares_parse_txt_reply()
48 */
49
ares_free_data(void * dataptr)50 void ares_free_data(void *dataptr)
51 {
52 while (dataptr != NULL) {
53 struct ares_data *ptr;
54 void *next_data = NULL;
55
56 #ifdef __INTEL_COMPILER
57 # pragma warning(push)
58 # pragma warning(disable : 1684)
59 /* 1684: conversion from pointer to same-sized integral type */
60 #endif
61
62 ptr = (void *)((char *)dataptr - offsetof(struct ares_data, data));
63
64 #ifdef __INTEL_COMPILER
65 # pragma warning(pop)
66 #endif
67
68 if (ptr->mark != ARES_DATATYPE_MARK) {
69 return;
70 }
71
72 switch (ptr->type) {
73 case ARES_DATATYPE_MX_REPLY:
74 next_data = ptr->data.mx_reply.next;
75 ares_free(ptr->data.mx_reply.host);
76 break;
77
78 case ARES_DATATYPE_SRV_REPLY:
79 next_data = ptr->data.srv_reply.next;
80 ares_free(ptr->data.srv_reply.host);
81 break;
82
83 case ARES_DATATYPE_URI_REPLY:
84 next_data = ptr->data.uri_reply.next;
85 ares_free(ptr->data.uri_reply.uri);
86 break;
87
88 case ARES_DATATYPE_TXT_REPLY:
89 case ARES_DATATYPE_TXT_EXT:
90 next_data = ptr->data.txt_reply.next;
91 ares_free(ptr->data.txt_reply.txt);
92 break;
93
94 case ARES_DATATYPE_ADDR_NODE:
95 next_data = ptr->data.addr_node.next;
96 break;
97
98 case ARES_DATATYPE_ADDR_PORT_NODE:
99 next_data = ptr->data.addr_port_node.next;
100 break;
101
102 case ARES_DATATYPE_NAPTR_REPLY:
103 next_data = ptr->data.naptr_reply.next;
104 ares_free(ptr->data.naptr_reply.flags);
105 ares_free(ptr->data.naptr_reply.service);
106 ares_free(ptr->data.naptr_reply.regexp);
107 ares_free(ptr->data.naptr_reply.replacement);
108 break;
109
110 case ARES_DATATYPE_SOA_REPLY:
111 ares_free(ptr->data.soa_reply.nsname);
112 ares_free(ptr->data.soa_reply.hostmaster);
113 break;
114
115 case ARES_DATATYPE_CAA_REPLY:
116 next_data = ptr->data.caa_reply.next;
117 ares_free(ptr->data.caa_reply.property);
118 ares_free(ptr->data.caa_reply.value);
119 break;
120
121 default:
122 return;
123 }
124
125 ares_free(ptr);
126 dataptr = next_data;
127 }
128 }
129
130 /*
131 ** ares_malloc_data() - c-ares internal helper function.
132 **
133 ** This function allocates memory for a c-ares private ares_data struct
134 ** for the specified ares_datatype, initializes c-ares private fields
135 ** and zero initializes those which later might be used from the public
136 ** API. It returns an interior pointer which can be passed by c-ares
137 ** functions to the calling application, and that must be free'ed using
138 ** c-ares external API function ares_free_data().
139 */
140
ares_malloc_data(ares_datatype type)141 void *ares_malloc_data(ares_datatype type)
142 {
143 struct ares_data *ptr;
144
145 ptr = ares_malloc_zero(sizeof(*ptr));
146 if (!ptr) {
147 return NULL;
148 }
149
150 switch (type) {
151 case ARES_DATATYPE_MX_REPLY:
152 case ARES_DATATYPE_SRV_REPLY:
153 case ARES_DATATYPE_URI_REPLY:
154 case ARES_DATATYPE_TXT_EXT:
155 case ARES_DATATYPE_TXT_REPLY:
156 case ARES_DATATYPE_CAA_REPLY:
157 case ARES_DATATYPE_ADDR_NODE:
158 case ARES_DATATYPE_ADDR_PORT_NODE:
159 case ARES_DATATYPE_NAPTR_REPLY:
160 case ARES_DATATYPE_SOA_REPLY:
161 break;
162
163 default:
164 ares_free(ptr);
165 return NULL;
166 }
167
168 ptr->mark = ARES_DATATYPE_MARK;
169 ptr->type = type;
170
171 return &ptr->data;
172 }
173