summaryrefslogtreecommitdiff
path: root/lib/hostip.h
blob: 3743b73961e1842867b0f1ebf94d449eddeca2c7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
#ifndef HEADER_CURL_HOSTIP_H
#define HEADER_CURL_HOSTIP_H
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at https://curl.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * SPDX-License-Identifier: curl
 *
 ***************************************************************************/

#include "curl_setup.h"
#include "hash.h"
#include "curl_addrinfo.h"
#include "curlx/timeval.h" /* for timediff_t */
#include "asyn.h"
#include "httpsrr.h"

#include <setjmp.h>

#ifdef USE_HTTPSRR
# include <stdint.h>
#endif

/* Allocate enough memory to hold the full name information structs and
 * everything. OSF1 is known to require at least 8872 bytes. The buffer
 * required for storing all possible aliases and IP numbers is according to
 * Stevens' Unix Network Programming 2nd edition, p. 304: 8192 bytes!
 */
#define CURL_HOSTENT_SIZE 9000

#define CURL_TIMEOUT_RESOLVE 300 /* when using asynch methods, we allow this
                                    many seconds for a name resolve */

#define CURL_ASYNC_SUCCESS CURLE_OK

struct addrinfo;
struct hostent;
struct Curl_easy;
struct connectdata;
struct easy_pollset;

enum alpnid {
  ALPN_none = 0,
  ALPN_h1 = CURLALTSVC_H1,
  ALPN_h2 = CURLALTSVC_H2,
  ALPN_h3 = CURLALTSVC_H3
};

struct Curl_dns_entry {
  struct Curl_addrinfo *addr;
#ifdef USE_HTTPSRR
  struct Curl_https_rrinfo *hinfo;
#endif
  /* timestamp == 0 -- permanent CURLOPT_RESOLVE entry (does not time out) */
  struct curltime timestamp;
  /* reference counter, entry is freed on reaching 0 */
  size_t refcount;
  /* hostname port number that resolved to addr. */
  int hostport;
  /* hostname that resolved to addr. may be NULL (Unix domain sockets). */
  char hostname[1];
};

struct Curl_dnscache {
  struct Curl_hash entries;
};

bool Curl_host_is_ipnum(const char *hostname);

/*
 * Curl_resolv() returns an entry with the info for the specified host
 * and port.
 *
 * The returned data *MUST* be "released" with Curl_resolv_unlink() after
 * use, or we will leak memory!
 */
CURLcode Curl_resolv(struct Curl_easy *data,
                     const char *hostname,
                     int port,
                     int ip_version,
                     bool allowDOH,
                     struct Curl_dns_entry **dnsentry);

CURLcode Curl_resolv_blocking(struct Curl_easy *data,
                              const char *hostname,
                              int port,
                              int ip_version,
                              struct Curl_dns_entry **dnsentry);

CURLcode Curl_resolv_timeout(struct Curl_easy *data,
                             const char *hostname, int port,
                             int ip_version,
                             struct Curl_dns_entry **dnsentry,
                             timediff_t timeoutms);

#ifdef USE_IPV6
/*
 * Curl_ipv6works() returns TRUE if IPv6 seems to work.
 */
bool Curl_ipv6works(struct Curl_easy *data);
#else
#define Curl_ipv6works(x) FALSE
#endif


/* unlink a dns entry, potentially shared with a cache */
void Curl_resolv_unlink(struct Curl_easy *data,
                        struct Curl_dns_entry **pdns);

/* init a new dns cache */
void Curl_dnscache_init(struct Curl_dnscache *dns, size_t hashsize);

void Curl_dnscache_destroy(struct Curl_dnscache *dns);

/* prune old entries from the DNS cache */
void Curl_dnscache_prune(struct Curl_easy *data);

/* clear the DNS cache */
void Curl_dnscache_clear(struct Curl_easy *data);

/* IPv4 threadsafe resolve function used for synch and asynch builds */
struct Curl_addrinfo *Curl_ipv4_resolve_r(const char *hostname, int port);

CURLcode Curl_once_resolved(struct Curl_easy *data,
                            struct Curl_dns_entry *dns,
                            bool *protocol_connect);

/*
 * Curl_printable_address() returns a printable version of the 1st address
 * given in the 'ip' argument. The result will be stored in the buf that is
 * bufsize bytes big.
 */
void Curl_printable_address(const struct Curl_addrinfo *ip,
                            char *buf, size_t bufsize);

/*
 * Make a `Curl_dns_entry`.
 * Creates a dnscache entry *without* adding it to a dnscache. This allows
 * further modifications of the entry *before* then adding it to a cache.
 *
 * The entry is created with a reference count of 1.
 * Use `Curl_resolv_unlink()` to release your hold on it.
 *
 * The call takes ownership of `addr`and makes a copy of `hostname`.
 *
 * Returns entry or NULL on OOM.
 */
struct Curl_dns_entry *
Curl_dnscache_mk_entry(struct Curl_easy *data,
                       struct Curl_addrinfo *addr,
                       const char *hostname,
                       size_t hostlen, /* length or zero */
                       int port,
                       bool permanent);

/*
 * Curl_dnscache_get() fetches a 'Curl_dns_entry' already in the DNS cache.
 *
 * Returns the Curl_dns_entry entry pointer or NULL if not in the cache.
 *
 * The returned data *MUST* be "released" with Curl_resolv_unlink() after
 * use, or we will leak memory!
 */
struct Curl_dns_entry *
Curl_dnscache_get(struct Curl_easy *data,
                  const char *hostname,
                  int port, int ip_version);

/*
 * Curl_dnscache_addr() adds `entry` to the cache, increasing its
 * reference count on success.
 */
CURLcode Curl_dnscache_add(struct Curl_easy *data,
                           struct Curl_dns_entry *entry);

/*
 * Populate the cache with specified entries from CURLOPT_RESOLVE.
 */
CURLcode Curl_loadhostpairs(struct Curl_easy *data);

#ifdef USE_CURL_ASYNC
CURLcode Curl_resolv_check(struct Curl_easy *data,
                           struct Curl_dns_entry **dns);
#else
#define Curl_resolv_check(x,y) CURLE_NOT_BUILT_IN
#endif
CURLcode Curl_resolv_pollset(struct Curl_easy *data,
                             struct easy_pollset *ps);

CURLcode Curl_resolver_error(struct Curl_easy *data);

#ifdef CURLRES_SYNCH
/*
 * Curl_sync_getaddrinfo() is the non-async low-level name resolve API.
 * There are several versions of this function - depending on IPV6
 * support and platform.
 */
struct Curl_addrinfo *Curl_sync_getaddrinfo(struct Curl_easy *data,
                                            const char *hostname,
                                            int port,
                                            int ip_version);

#endif

#endif /* HEADER_CURL_HOSTIP_H */