1#ifndef HEADER_CURL_HOSTIP_H
2#define HEADER_CURL_HOSTIP_H
3/***************************************************************************
4 * _ _ ____ _
5 * Project ___| | | | _ \| |
6 * / __| | | | |_) | |
7 * | (__| |_| | _ <| |___
8 * \___|\___/|_| \_\_____|
9 *
10 * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
11 *
12 * This software is licensed as described in the file COPYING, which
13 * you should have received as part of this distribution. The terms
14 * are also available at https://curl.haxx.se/docs/copyright.html.
15 *
16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
17 * copies of the Software, and permit persons to whom the Software is
18 * furnished to do so, under the terms of the COPYING file.
19 *
20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
21 * KIND, either express or implied.
22 *
23 ***************************************************************************/
24
25#include "curl_setup.h"
26#include "hash.h"
27#include "curl_addrinfo.h"
28#include "timeval.h" /* for timediff_t */
29#include "asyn.h"
30
31#ifdef HAVE_SETJMP_H
32#include <setjmp.h>
33#endif
34
35#ifdef NETWARE
36#undef in_addr_t
37#define in_addr_t unsigned long
38#endif
39
40/* Allocate enough memory to hold the full name information structs and
41 * everything. OSF1 is known to require at least 8872 bytes. The buffer
42 * required for storing all possible aliases and IP numbers is according to
43 * Stevens' Unix Network Programming 2nd edition, p. 304: 8192 bytes!
44 */
45#define CURL_HOSTENT_SIZE 9000
46
47#define CURL_TIMEOUT_RESOLVE 300 /* when using asynch methods, we allow this
48 many seconds for a name resolve */
49
50#define CURL_ASYNC_SUCCESS CURLE_OK
51
52struct addrinfo;
53struct hostent;
54struct Curl_easy;
55struct connectdata;
56
57/*
58 * Curl_global_host_cache_init() initializes and sets up a global DNS cache.
59 * Global DNS cache is general badness. Do not use. This will be removed in
60 * a future version. Use the share interface instead!
61 *
62 * Returns a struct curl_hash pointer on success, NULL on failure.
63 */
64struct curl_hash *Curl_global_host_cache_init(void);
65
66struct Curl_dns_entry {
67 Curl_addrinfo *addr;
68 /* timestamp == 0 -- CURLOPT_RESOLVE entry, doesn't timeout */
69 time_t timestamp;
70 /* use-counter, use Curl_resolv_unlock to release reference */
71 long inuse;
72};
73
74/*
75 * Curl_resolv() returns an entry with the info for the specified host
76 * and port.
77 *
78 * The returned data *MUST* be "unlocked" with Curl_resolv_unlock() after
79 * use, or we'll leak memory!
80 */
81/* return codes */
82#define CURLRESOLV_TIMEDOUT -2
83#define CURLRESOLV_ERROR -1
84#define CURLRESOLV_RESOLVED 0
85#define CURLRESOLV_PENDING 1
86int Curl_resolv(struct connectdata *conn,
87 const char *hostname,
88 int port,
89 bool allowDOH,
90 struct Curl_dns_entry **dnsentry);
91int Curl_resolv_timeout(struct connectdata *conn, const char *hostname,
92 int port, struct Curl_dns_entry **dnsentry,
93 timediff_t timeoutms);
94
95#ifdef CURLRES_IPV6
96/*
97 * Curl_ipv6works() returns TRUE if IPv6 seems to work.
98 */
99bool Curl_ipv6works(void);
100#else
101#define Curl_ipv6works() FALSE
102#endif
103
104/*
105 * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've
106 * been set and returns TRUE if they are OK.
107 */
108bool Curl_ipvalid(struct connectdata *conn);
109
110
111/*
112 * Curl_getaddrinfo() is the generic low-level name resolve API within this
113 * source file. There are several versions of this function - for different
114 * name resolve layers (selected at build-time). They all take this same set
115 * of arguments
116 */
117Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn,
118 const char *hostname,
119 int port,
120 int *waitp);
121
122
123/* unlock a previously resolved dns entry */
124void Curl_resolv_unlock(struct Curl_easy *data,
125 struct Curl_dns_entry *dns);
126
127/* init a new dns cache and return success */
128int Curl_mk_dnscache(struct curl_hash *hash);
129
130/* prune old entries from the DNS cache */
131void Curl_hostcache_prune(struct Curl_easy *data);
132
133/* Return # of addresses in a Curl_addrinfo struct */
134int Curl_num_addresses(const Curl_addrinfo *addr);
135
136#if defined(CURLDEBUG) && defined(HAVE_GETNAMEINFO)
137int curl_dogetnameinfo(GETNAMEINFO_QUAL_ARG1 GETNAMEINFO_TYPE_ARG1 sa,
138 GETNAMEINFO_TYPE_ARG2 salen,
139 char *host, GETNAMEINFO_TYPE_ARG46 hostlen,
140 char *serv, GETNAMEINFO_TYPE_ARG46 servlen,
141 GETNAMEINFO_TYPE_ARG7 flags,
142 int line, const char *source);
143#endif
144
145/* IPv4 threadsafe resolve function used for synch and asynch builds */
146Curl_addrinfo *Curl_ipv4_resolve_r(const char *hostname, int port);
147
148CURLcode Curl_once_resolved(struct connectdata *conn, bool *protocol_connect);
149
150/*
151 * Curl_addrinfo_callback() is used when we build with any asynch specialty.
152 * Handles end of async request processing. Inserts ai into hostcache when
153 * status is CURL_ASYNC_SUCCESS. Twiddles fields in conn to indicate async
154 * request completed whether successful or failed.
155 */
156CURLcode Curl_addrinfo_callback(struct connectdata *conn,
157 int status,
158 Curl_addrinfo *ai);
159
160/*
161 * Curl_printable_address() returns a printable version of the 1st address
162 * given in the 'ip' argument. The result will be stored in the buf that is
163 * bufsize bytes big.
164 */
165const char *Curl_printable_address(const Curl_addrinfo *ip,
166 char *buf, size_t bufsize);
167
168/*
169 * Curl_fetch_addr() fetches a 'Curl_dns_entry' already in the DNS cache.
170 *
171 * Returns the Curl_dns_entry entry pointer or NULL if not in the cache.
172 *
173 * The returned data *MUST* be "unlocked" with Curl_resolv_unlock() after
174 * use, or we'll leak memory!
175 */
176struct Curl_dns_entry *
177Curl_fetch_addr(struct connectdata *conn,
178 const char *hostname,
179 int port);
180
181/*
182 * Curl_cache_addr() stores a 'Curl_addrinfo' struct in the DNS cache.
183 *
184 * Returns the Curl_dns_entry entry pointer or NULL if the storage failed.
185 */
186struct Curl_dns_entry *
187Curl_cache_addr(struct Curl_easy *data, Curl_addrinfo *addr,
188 const char *hostname, int port);
189
190#ifndef INADDR_NONE
191#define CURL_INADDR_NONE (in_addr_t) ~0
192#else
193#define CURL_INADDR_NONE INADDR_NONE
194#endif
195
196#ifdef HAVE_SIGSETJMP
197/* Forward-declaration of variable defined in hostip.c. Beware this
198 * is a global and unique instance. This is used to store the return
199 * address that we can jump back to from inside a signal handler.
200 * This is not thread-safe stuff.
201 */
202extern sigjmp_buf curl_jmpenv;
203#endif
204
205/*
206 * Function provided by the resolver backend to set DNS servers to use.
207 */
208CURLcode Curl_set_dns_servers(struct Curl_easy *data, char *servers);
209
210/*
211 * Function provided by the resolver backend to set
212 * outgoing interface to use for DNS requests
213 */
214CURLcode Curl_set_dns_interface(struct Curl_easy *data,
215 const char *interf);
216
217/*
218 * Function provided by the resolver backend to set
219 * local IPv4 address to use as source address for DNS requests
220 */
221CURLcode Curl_set_dns_local_ip4(struct Curl_easy *data,
222 const char *local_ip4);
223
224/*
225 * Function provided by the resolver backend to set
226 * local IPv6 address to use as source address for DNS requests
227 */
228CURLcode Curl_set_dns_local_ip6(struct Curl_easy *data,
229 const char *local_ip6);
230
231/*
232 * Clean off entries from the cache
233 */
234void Curl_hostcache_clean(struct Curl_easy *data, struct curl_hash *hash);
235
236/*
237 * Populate the cache with specified entries from CURLOPT_RESOLVE.
238 */
239CURLcode Curl_loadhostpairs(struct Curl_easy *data);
240
241CURLcode Curl_resolv_check(struct connectdata *conn,
242 struct Curl_dns_entry **dns);
243int Curl_resolv_getsock(struct connectdata *conn,
244 curl_socket_t *socks);
245
246#endif /* HEADER_CURL_HOSTIP_H */
247