1 /***************************************************************************
2  *                                  _   _ ____  _
3  *  Project                     ___| | | |  _ \| |
4  *                             / __| | | | |_) | |
5  *                            | (__| |_| |  _ <| |___
6  *                             \___|\___/|_| \_\_____|
7  *
8  * Copyright (C) 1998 - 2020, 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.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_if2ip(int af,unsigned int remote_scope,unsigned int local_scope_id,const char * interf,char * buf,int buf_size)99 if2ip_result_t Curl_if2ip(int af, unsigned int remote_scope,
100                           unsigned int local_scope_id, const char *interf,
101                           char *buf, int buf_size)
102 {
103   struct ifaddrs *iface, *head;
104   if2ip_result_t res = IF2IP_NOT_FOUND;
105 
106 #ifndef ENABLE_IPV6
107   (void) remote_scope;
108 #endif
109 
110 #if !defined(HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID) || \
111     !defined(ENABLE_IPV6)
112   (void) local_scope_id;
113 #endif
114 
115   if(getifaddrs(&head) >= 0) {
116     for(iface = head; iface != NULL; iface = iface->ifa_next) {
117       if(iface->ifa_addr != NULL) {
118         if(iface->ifa_addr->sa_family == af) {
119           if(strcasecompare(iface->ifa_name, interf)) {
120             void *addr;
121             const char *ip;
122             char scope[12] = "";
123             char ipstr[64];
124 #ifdef ENABLE_IPV6
125             if(af == AF_INET6) {
126 #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID
127               unsigned int scopeid = 0;
128 #endif
129               unsigned int ifscope = Curl_ipv6_scope(iface->ifa_addr);
130 
131               if(ifscope != remote_scope) {
132                 /* We are interested only in interface addresses whose scope
133                    matches the remote address we want to connect to: global
134                    for global, link-local for link-local, etc... */
135                 if(res == IF2IP_NOT_FOUND)
136                   res = IF2IP_AF_NOT_SUPPORTED;
137                 continue;
138               }
139 
140               addr =
141                 &((struct sockaddr_in6 *)(void *)iface->ifa_addr)->sin6_addr;
142 #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID
143               /* Include the scope of this interface as part of the address */
144               scopeid = ((struct sockaddr_in6 *)(void *)iface->ifa_addr)
145                             ->sin6_scope_id;
146 
147               /* If given, scope id should match. */
148               if(local_scope_id && scopeid != local_scope_id) {
149                 if(res == IF2IP_NOT_FOUND)
150                   res = IF2IP_AF_NOT_SUPPORTED;
151 
152                 continue;
153               }
154 
155               if(scopeid)
156                 msnprintf(scope, sizeof(scope), "%%%u", scopeid);
157 #endif
158             }
159             else
160 #endif
161               addr =
162                 &((struct sockaddr_in *)(void *)iface->ifa_addr)->sin_addr;
163             res = IF2IP_FOUND;
164             ip = Curl_inet_ntop(af, addr, ipstr, sizeof(ipstr));
165             msnprintf(buf, buf_size, "%s%s", ip, scope);
166             break;
167           }
168         }
169         else if((res == IF2IP_NOT_FOUND) &&
170                 strcasecompare(iface->ifa_name, interf)) {
171           res = IF2IP_AF_NOT_SUPPORTED;
172         }
173       }
174     }
175 
176     freeifaddrs(head);
177   }
178 
179   return res;
180 }
181 
182 #elif defined(HAVE_IOCTL_SIOCGIFADDR)
183 
Curl_if2ip(int af,unsigned int remote_scope,unsigned int local_scope_id,const char * interf,char * buf,int buf_size)184 if2ip_result_t Curl_if2ip(int af, unsigned int remote_scope,
185                           unsigned int local_scope_id, const char *interf,
186                           char *buf, int buf_size)
187 {
188   struct ifreq req;
189   struct in_addr in;
190   struct sockaddr_in *s;
191   curl_socket_t dummy;
192   size_t len;
193   const char *r;
194 
195   (void)remote_scope;
196   (void)local_scope_id;
197 
198   if(!interf || (af != AF_INET))
199     return IF2IP_NOT_FOUND;
200 
201   len = strlen(interf);
202   if(len >= sizeof(req.ifr_name))
203     return IF2IP_NOT_FOUND;
204 
205   dummy = socket(AF_INET, SOCK_STREAM, 0);
206   if(CURL_SOCKET_BAD == dummy)
207     return IF2IP_NOT_FOUND;
208 
209   memset(&req, 0, sizeof(req));
210   memcpy(req.ifr_name, interf, len + 1);
211   req.ifr_addr.sa_family = AF_INET;
212 
213   if(ioctl(dummy, SIOCGIFADDR, &req) < 0) {
214     sclose(dummy);
215     /* With SIOCGIFADDR, we cannot tell the difference between an interface
216        that does not exist and an interface that has no address of the
217        correct family. Assume the interface does not exist */
218     return IF2IP_NOT_FOUND;
219   }
220 
221   s = (struct sockaddr_in *)(void *)&req.ifr_addr;
222   memcpy(&in, &s->sin_addr, sizeof(in));
223   r = Curl_inet_ntop(s->sin_family, &in, buf, buf_size);
224 
225   sclose(dummy);
226   if(!r)
227     return IF2IP_NOT_FOUND;
228   return IF2IP_FOUND;
229 }
230 
231 #else
232 
Curl_if2ip(int af,unsigned int remote_scope,unsigned int local_scope_id,const char * interf,char * buf,int buf_size)233 if2ip_result_t Curl_if2ip(int af, unsigned int remote_scope,
234                           unsigned int local_scope_id, const char *interf,
235                           char *buf, int buf_size)
236 {
237     (void) af;
238     (void) remote_scope;
239     (void) local_scope_id;
240     (void) interf;
241     (void) buf;
242     (void) buf_size;
243     return IF2IP_NOT_FOUND;
244 }
245 
246 #endif
247