1 /***************************************************************************
2  *                                  _   _ ____  _
3  *  Project                     ___| | | |  _ \| |
4  *                             / __| | | | |_) | |
5  *                            | (__| |_| |  _ <| |___
6  *                             \___|\___/|_| \_\_____|
7  *
8  * Copyright (C) 1998 - 2017, 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 #ifdef HAVE_NETINET_IN_H
26 #  include <netinet/in.h>
27 #endif
28 #ifdef HAVE_ARPA_INET_H
29 #  include <arpa/inet.h>
30 #endif
31 #ifdef HAVE_NET_IF_H
32 #  include <net/if.h>
33 #endif
34 #ifdef HAVE_SYS_IOCTL_H
35 #  include <sys/ioctl.h>
36 #endif
37 #ifdef HAVE_NETDB_H
38 #  include <netdb.h>
39 #endif
40 #ifdef HAVE_SYS_SOCKIO_H
41 #  include <sys/sockio.h>
42 #endif
43 #ifdef HAVE_IFADDRS_H
44 #  include <ifaddrs.h>
45 #endif
46 #ifdef HAVE_STROPTS_H
47 #  include <stropts.h>
48 #endif
49 #ifdef __VMS
50 #  include <inet.h>
51 #endif
52 
53 #include "inet_ntop.h"
54 #include "strcase.h"
55 #include "if2ip.h"
56 /* The last 3 #include files should be in this order */
57 #include "curl_printf.h"
58 #include "curl_memory.h"
59 #include "memdebug.h"
60 
61 /* ------------------------------------------------------------------ */
62 
63 /* Return the scope of the given address. */
Curl_ipv6_scope(const struct sockaddr * sa)64 unsigned int Curl_ipv6_scope(const struct sockaddr *sa)
65 {
66 #ifndef ENABLE_IPV6
67   (void) sa;
68 #else
69   if(sa->sa_family == AF_INET6) {
70     const struct sockaddr_in6 * sa6 = (const struct sockaddr_in6 *)(void *) sa;
71     const unsigned char *b = sa6->sin6_addr.s6_addr;
72     unsigned short w = (unsigned short) ((b[0] << 8) | b[1]);
73 
74     if((b[0] & 0xFE) == 0xFC) /* Handle ULAs */
75       return IPV6_SCOPE_UNIQUELOCAL;
76     switch(w & 0xFFC0) {
77     case 0xFE80:
78       return IPV6_SCOPE_LINKLOCAL;
79     case 0xFEC0:
80       return IPV6_SCOPE_SITELOCAL;
81     case 0x0000:
82       w = b[1] | b[2] | b[3] | b[4] | b[5] | b[6] | b[7] | b[8] | b[9] |
83           b[10] | b[11] | b[12] | b[13] | b[14];
84       if(w || b[15] != 0x01)
85         break;
86       return IPV6_SCOPE_NODELOCAL;
87     default:
88       break;
89     }
90   }
91 #endif
92 
93   return IPV6_SCOPE_GLOBAL;
94 }
95 
96 
97 #if defined(HAVE_GETIFADDRS)
98 
Curl_if_is_interface_name(const char * interf)99 bool Curl_if_is_interface_name(const char *interf)
100 {
101   bool result = FALSE;
102 
103   struct ifaddrs *iface, *head;
104 
105   if(getifaddrs(&head) >= 0) {
106     for(iface = head; iface != NULL; iface = iface->ifa_next) {
107       if(strcasecompare(iface->ifa_name, interf)) {
108         result = TRUE;
109         break;
110       }
111     }
112     freeifaddrs(head);
113   }
114   return result;
115 }
116 
Curl_if2ip(int af,unsigned int remote_scope,unsigned int remote_scope_id,const char * interf,char * buf,int buf_size)117 if2ip_result_t Curl_if2ip(int af, unsigned int remote_scope,
118                           unsigned int remote_scope_id, const char *interf,
119                           char *buf, int buf_size)
120 {
121   struct ifaddrs *iface, *head;
122   if2ip_result_t res = IF2IP_NOT_FOUND;
123 
124 #ifndef ENABLE_IPV6
125   (void) remote_scope;
126 #endif
127 
128 #if !defined(HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID) || \
129     !defined(ENABLE_IPV6)
130   (void) remote_scope_id;
131 #endif
132 
133   if(getifaddrs(&head) >= 0) {
134     for(iface = head; iface != NULL; iface = iface->ifa_next) {
135       if(iface->ifa_addr != NULL) {
136         if(iface->ifa_addr->sa_family == af) {
137           if(strcasecompare(iface->ifa_name, interf)) {
138             void *addr;
139             char *ip;
140             char scope[12] = "";
141             char ipstr[64];
142 #ifdef ENABLE_IPV6
143             if(af == AF_INET6) {
144               unsigned int scopeid = 0;
145               unsigned int ifscope = Curl_ipv6_scope(iface->ifa_addr);
146 
147               if(ifscope != remote_scope) {
148                 /* We are interested only in interface addresses whose
149                    scope matches the remote address we want to
150                    connect to: global for global, link-local for
151                    link-local, etc... */
152                 if(res == IF2IP_NOT_FOUND) res = IF2IP_AF_NOT_SUPPORTED;
153                 continue;
154               }
155 
156               addr =
157                 &((struct sockaddr_in6 *)(void *)iface->ifa_addr)->sin6_addr;
158 #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID
159               /* Include the scope of this interface as part of the address */
160               scopeid = ((struct sockaddr_in6 *)(void *)iface->ifa_addr)
161                             ->sin6_scope_id;
162 
163               /* If given, scope id should match. */
164               if(remote_scope_id && scopeid != remote_scope_id) {
165                 if(res == IF2IP_NOT_FOUND)
166                   res = IF2IP_AF_NOT_SUPPORTED;
167 
168                 continue;
169               }
170 #endif
171               if(scopeid)
172                 snprintf(scope, sizeof(scope), "%%%u", scopeid);
173             }
174             else
175 #endif
176               addr =
177                   &((struct sockaddr_in *)(void *)iface->ifa_addr)->sin_addr;
178             res = IF2IP_FOUND;
179             ip = (char *) Curl_inet_ntop(af, addr, ipstr, sizeof(ipstr));
180             snprintf(buf, buf_size, "%s%s", ip, scope);
181             break;
182           }
183         }
184         else if((res == IF2IP_NOT_FOUND) &&
185                 strcasecompare(iface->ifa_name, interf)) {
186           res = IF2IP_AF_NOT_SUPPORTED;
187         }
188       }
189     }
190 
191     freeifaddrs(head);
192   }
193 
194   return res;
195 }
196 
197 #elif defined(HAVE_IOCTL_SIOCGIFADDR)
198 
Curl_if_is_interface_name(const char * interf)199 bool Curl_if_is_interface_name(const char *interf)
200 {
201   /* This is here just to support the old interfaces */
202   char buf[256];
203 
204   return (Curl_if2ip(AF_INET, 0 /* unused */, 0, interf, buf, sizeof(buf)) ==
205           IF2IP_NOT_FOUND) ? FALSE : TRUE;
206 }
207 
Curl_if2ip(int af,unsigned int remote_scope,unsigned int remote_scope_id,const char * interf,char * buf,int buf_size)208 if2ip_result_t Curl_if2ip(int af, unsigned int remote_scope,
209                           unsigned int remote_scope_id, const char *interf,
210                           char *buf, int buf_size)
211 {
212   struct ifreq req;
213   struct in_addr in;
214   struct sockaddr_in *s;
215   curl_socket_t dummy;
216   size_t len;
217 
218   (void)remote_scope;
219   (void)remote_scope_id;
220 
221   if(!interf || (af != AF_INET))
222     return IF2IP_NOT_FOUND;
223 
224   len = strlen(interf);
225   if(len >= sizeof(req.ifr_name))
226     return IF2IP_NOT_FOUND;
227 
228   dummy = socket(AF_INET, SOCK_STREAM, 0);
229   if(CURL_SOCKET_BAD == dummy)
230     return IF2IP_NOT_FOUND;
231 
232   memset(&req, 0, sizeof(req));
233   memcpy(req.ifr_name, interf, len + 1);
234   req.ifr_addr.sa_family = AF_INET;
235 
236   if(ioctl(dummy, SIOCGIFADDR, &req) < 0) {
237     sclose(dummy);
238     /* With SIOCGIFADDR, we cannot tell the difference between an interface
239        that does not exist and an interface that has no address of the
240        correct family. Assume the interface does not exist */
241     return IF2IP_NOT_FOUND;
242   }
243 
244   s = (struct sockaddr_in *)(void *)&req.ifr_addr;
245   memcpy(&in, &s->sin_addr, sizeof(in));
246   Curl_inet_ntop(s->sin_family, &in, buf, buf_size);
247 
248   sclose(dummy);
249   return IF2IP_FOUND;
250 }
251 
252 #else
253 
Curl_if_is_interface_name(const char * interf)254 bool Curl_if_is_interface_name(const char *interf)
255 {
256   (void) interf;
257 
258   return FALSE;
259 }
260 
Curl_if2ip(int af,unsigned int remote_scope,unsigned int remote_scope_id,const char * interf,char * buf,int buf_size)261 if2ip_result_t Curl_if2ip(int af, unsigned int remote_scope,
262                           unsigned int remote_scope_id, const char *interf,
263                           char *buf, int buf_size)
264 {
265     (void) af;
266     (void) remote_scope;
267     (void) remote_scope_id;
268     (void) interf;
269     (void) buf;
270     (void) buf_size;
271     return IF2IP_NOT_FOUND;
272 }
273 
274 #endif
275