1/***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22
23#include "curl_setup.h"
24
25/***********************************************************************
26 * Only for IPv6-enabled builds
27 **********************************************************************/
28#ifdef CURLRES_IPV6
29
30#ifdef HAVE_NETINET_IN_H
31#include <netinet/in.h>
32#endif
33#ifdef HAVE_NETDB_H
34#include <netdb.h>
35#endif
36#ifdef HAVE_ARPA_INET_H
37#include <arpa/inet.h>
38#endif
39#ifdef __VMS
40#include <in.h>
41#include <inet.h>
42#endif
43
44#ifdef HAVE_PROCESS_H
45#include <process.h>
46#endif
47
48#include "urldata.h"
49#include "sendf.h"
50#include "hostip.h"
51#include "hash.h"
52#include "share.h"
53#include "strerror.h"
54#include "url.h"
55#include "inet_pton.h"
56#include "connect.h"
57/* The last 3 #include files should be in this order */
58#include "curl_printf.h"
59#include "curl_memory.h"
60#include "memdebug.h"
61
62/*
63 * Curl_ipv6works() returns TRUE if IPv6 seems to work.
64 */
65bool Curl_ipv6works(void)
66{
67 /* the nature of most system is that IPv6 status doesn't come and go
68 during a program's lifetime so we only probe the first time and then we
69 have the info kept for fast re-use */
70 static int ipv6_works = -1;
71 if(-1 == ipv6_works) {
72 /* probe to see if we have a working IPv6 stack */
73 curl_socket_t s = socket(PF_INET6, SOCK_DGRAM, 0);
74 if(s == CURL_SOCKET_BAD)
75 /* an IPv6 address was requested but we can't get/use one */
76 ipv6_works = 0;
77 else {
78 ipv6_works = 1;
79 Curl_closesocket(NULL, s);
80 }
81 }
82 return (ipv6_works>0)?TRUE:FALSE;
83}
84
85/*
86 * Curl_ipvalid() checks what CURL_IPRESOLVE_* requirements that might've
87 * been set and returns TRUE if they are OK.
88 */
89bool Curl_ipvalid(struct connectdata *conn)
90{
91 if(conn->ip_version == CURL_IPRESOLVE_V6)
92 return Curl_ipv6works();
93
94 return TRUE;
95}
96
97#if defined(CURLRES_SYNCH)
98
99#ifdef DEBUG_ADDRINFO
100static void dump_addrinfo(struct connectdata *conn, const Curl_addrinfo *ai)
101{
102 printf("dump_addrinfo:\n");
103 for(; ai; ai = ai->ai_next) {
104 char buf[INET6_ADDRSTRLEN];
105 printf(" fam %2d, CNAME %s, ",
106 ai->ai_family, ai->ai_canonname ? ai->ai_canonname : "<none>");
107 if(Curl_printable_address(ai, buf, sizeof(buf)))
108 printf("%s\n", buf);
109 else {
110 char buffer[STRERROR_LEN];
111 printf("failed; %s\n",
112 Curl_strerror(SOCKERRNO, buffer, sizeof(buffer)));
113 }
114 }
115}
116#else
117#define dump_addrinfo(x,y) Curl_nop_stmt
118#endif
119
120/*
121 * Curl_getaddrinfo() when built IPv6-enabled (non-threading and
122 * non-ares version).
123 *
124 * Returns name information about the given hostname and port number. If
125 * successful, the 'addrinfo' is returned and the forth argument will point to
126 * memory we need to free after use. That memory *MUST* be freed with
127 * Curl_freeaddrinfo(), nothing else.
128 */
129Curl_addrinfo *Curl_getaddrinfo(struct connectdata *conn,
130 const char *hostname,
131 int port,
132 int *waitp)
133{
134 struct addrinfo hints;
135 Curl_addrinfo *res;
136 int error;
137 char sbuf[12];
138 char *sbufptr = NULL;
139#ifndef USE_RESOLVE_ON_IPS
140 char addrbuf[128];
141#endif
142 int pf;
143#if !defined(CURL_DISABLE_VERBOSE_STRINGS)
144 struct Curl_easy *data = conn->data;
145#endif
146
147 *waitp = 0; /* synchronous response only */
148
149 /* Check if a limited name resolve has been requested */
150 switch(conn->ip_version) {
151 case CURL_IPRESOLVE_V4:
152 pf = PF_INET;
153 break;
154 case CURL_IPRESOLVE_V6:
155 pf = PF_INET6;
156 break;
157 default:
158 pf = PF_UNSPEC;
159 break;
160 }
161
162 if((pf != PF_INET) && !Curl_ipv6works())
163 /* The stack seems to be a non-IPv6 one */
164 pf = PF_INET;
165
166 memset(&hints, 0, sizeof(hints));
167 hints.ai_family = pf;
168 hints.ai_socktype = (conn->transport == TRNSPRT_TCP) ?
169 SOCK_STREAM : SOCK_DGRAM;
170
171#ifndef USE_RESOLVE_ON_IPS
172 /*
173 * The AI_NUMERICHOST must not be set to get synthesized IPv6 address from
174 * an IPv4 address on iOS and Mac OS X.
175 */
176 if((1 == Curl_inet_pton(AF_INET, hostname, addrbuf)) ||
177 (1 == Curl_inet_pton(AF_INET6, hostname, addrbuf))) {
178 /* the given address is numerical only, prevent a reverse lookup */
179 hints.ai_flags = AI_NUMERICHOST;
180 }
181#endif
182
183 if(port) {
184 msnprintf(sbuf, sizeof(sbuf), "%d", port);
185 sbufptr = sbuf;
186 }
187
188 error = Curl_getaddrinfo_ex(hostname, sbufptr, &hints, &res);
189 if(error) {
190 infof(data, "getaddrinfo(3) failed for %s:%d\n", hostname, port);
191 return NULL;
192 }
193
194 if(port) {
195 Curl_addrinfo_set_port(res, port);
196 }
197
198 dump_addrinfo(conn, res);
199
200 return res;
201}
202#endif /* CURLRES_SYNCH */
203
204#endif /* CURLRES_IPV6 */
205