summaryrefslogtreecommitdiff
path: root/lib/hostip.h
blob: 1bda524be49e0a634ac3acbb889015de39b1c9e0 (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
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
#ifndef HEADER_CURL_HOSTIP_H
#define HEADER_CURL_HOSTIP_H
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2019, 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.haxx.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.
 *
 ***************************************************************************/

#include "curl_setup.h"
#include "hash.h"
#include "curl_addrinfo.h"
#include "asyn.h"

#ifdef HAVE_SETJMP_H
#include <setjmp.h>
#endif

#ifdef NETWARE
#undef in_addr_t
#define in_addr_t unsigned long
#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;

/*
 * Curl_global_host_cache_init() initializes and sets up a global DNS cache.
 * Global DNS cache is general badness. Do not use. This will be removed in
 * a future version. Use the share interface instead!
 *
 * Returns a struct curl_hash pointer on success, NULL on failure.
 */
struct curl_hash *Curl_global_host_cache_init(void);

struct Curl_dns_entry {
  Curl_addrinfo *addr;
  /* timestamp == 0 -- CURLOPT_RESOLVE entry, doesn't timeout */
  time_t timestamp;
  /* use-counter, use Curl_resolv_unlock to release reference */
  long inuse;
};

/*
 * Curl_resolv() returns an entry with the info for the specified host
 * and port.
 *
 * The returned data *MUST* be "unlocked" with Curl_resolv_unlock() after
 * use, or we'll leak memory!
 */
/* return codes */
#define CURLRESOLV_TIMEDOUT -2
#define CURLRESOLV_ERROR    -1
#define CURLRESOLV_RESOLVED  0
#define CURLRESOLV_PENDING   1
int Curl_resolv(struct connectdata *conn,
                const char *hostname,
                int port,
                bool allowDOH,
                struct Curl_dns_entry **dnsentry);
int Curl_resolv_timeout(struct connectdata *conn, const char *hostname,
                        int port, struct Curl_dns_entry **dnsentry,
                        time_t timeoutms);

#ifdef CURLRES_IPV6
/*
 * Curl_ipv6works() returns TRUE if IPv6 seems to work.
 */
bool Curl_ipv6works(void);
#else
#define Curl_ipv6works() FALSE
#endif

/*
 * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've
 * been set and returns TRUE if they are OK.
 */
bool Curl_ipvalid(struct connectdata *conn);


/*
 * Curl_getaddrinfo() is the generic low-level name resolve API within this
 * source file. There are several versions of this function - for different
 * name resolve layers (selected at build-time). They all take this same set
 * of arguments
 */
Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn,
                                const char *hostname,
                                int port,
                                int *waitp);


/* unlock a previously resolved dns entry */
void Curl_resolv_unlock(struct Curl_easy *data,
                        struct Curl_dns_entry *dns);

/* init a new dns cache and return success */
int Curl_mk_dnscache(struct curl_hash *hash);

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

/* Return # of addresses in a Curl_addrinfo struct */
int Curl_num_addresses(const Curl_addrinfo *addr);

#if defined(CURLDEBUG) && defined(HAVE_GETNAMEINFO)
int curl_dogetnameinfo(GETNAMEINFO_QUAL_ARG1 GETNAMEINFO_TYPE_ARG1 sa,
                       GETNAMEINFO_TYPE_ARG2 salen,
                       char *host, GETNAMEINFO_TYPE_ARG46 hostlen,
                       char *serv, GETNAMEINFO_TYPE_ARG46 servlen,
                       GETNAMEINFO_TYPE_ARG7 flags,
                       int line, const char *source);
#endif

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

CURLcode Curl_once_resolved(struct connectdata *conn, bool *protocol_connect);

/*
 * Curl_addrinfo_callback() is used when we build with any asynch specialty.
 * Handles end of async request processing. Inserts ai into hostcache when
 * status is CURL_ASYNC_SUCCESS. Twiddles fields in conn to indicate async
 * request completed whether successful or failed.
 */
CURLcode Curl_addrinfo_callback(struct connectdata *conn,
                                int status,
                                Curl_addrinfo *ai);

/*
 * 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.
 */
const char *Curl_printable_address(const Curl_addrinfo *ip,
                                   char *buf, size_t bufsize);

/*
 * Curl_fetch_addr() 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 "unlocked" with Curl_resolv_unlock() after
 * use, or we'll leak memory!
 */
struct Curl_dns_entry *
Curl_fetch_addr(struct connectdata *conn,
                const char *hostname,
                int port);

/*
 * Curl_cache_addr() stores a 'Curl_addrinfo' struct in the DNS cache.
 *
 * Returns the Curl_dns_entry entry pointer or NULL if the storage failed.
 */
struct Curl_dns_entry *
Curl_cache_addr(struct Curl_easy *data, Curl_addrinfo *addr,
                const char *hostname, int port);

#ifndef INADDR_NONE
#define CURL_INADDR_NONE (in_addr_t) ~0
#else
#define CURL_INADDR_NONE INADDR_NONE
#endif

#ifdef HAVE_SIGSETJMP
/* Forward-declaration of variable defined in hostip.c. Beware this
 * is a global and unique instance. This is used to store the return
 * address that we can jump back to from inside a signal handler.
 * This is not thread-safe stuff.
 */
extern sigjmp_buf curl_jmpenv;
#endif

/*
 * Function provided by the resolver backend to set DNS servers to use.
 */
CURLcode Curl_set_dns_servers(struct Curl_easy *data, char *servers);

/*
 * Function provided by the resolver backend to set
 * outgoing interface to use for DNS requests
 */
CURLcode Curl_set_dns_interface(struct Curl_easy *data,
                                const char *interf);

/*
 * Function provided by the resolver backend to set
 * local IPv4 address to use as source address for DNS requests
 */
CURLcode Curl_set_dns_local_ip4(struct Curl_easy *data,
                                const char *local_ip4);

/*
 * Function provided by the resolver backend to set
 * local IPv6 address to use as source address for DNS requests
 */
CURLcode Curl_set_dns_local_ip6(struct Curl_easy *data,
                                const char *local_ip6);

/*
 * Clean off entries from the cache
 */
void Curl_hostcache_clean(struct Curl_easy *data, struct curl_hash *hash);

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

CURLcode Curl_resolv_check(struct connectdata *conn,
                           struct Curl_dns_entry **dns);
int Curl_resolv_getsock(struct connectdata *conn,
                        curl_socket_t *socks,
                        int numsocks);

#endif /* HEADER_CURL_HOSTIP_H */