Utilities/cmcurl/lib/if2ip.c

   1 /***************************************************************************
   2  *                                  _   _ ____  _
   3  *  Project                     ___| | | |  _ \| |
   4  *                             / __| | | | |_) | |
   5  *                            | (__| |_| |  _ <| |___
   6  *                             \___|\___/|_| \_\_____|
   7  *
   8  * Copyright (C) 1998 - 2022, 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 #ifdef ENABLE_IPV6
  64 /* Return the scope of the given address. */
  65 unsigned int Curl_ipv6_scope(const struct sockaddr *sa)
  66 {
  67   if(sa->sa_family == AF_INET6) {
  68     const struct sockaddr_in6 * sa6 = (const struct sockaddr_in6 *)(void *) sa;
  69     const unsigned char *b = sa6->sin6_addr.s6_addr;
  70     unsigned short w = (unsigned short) ((b[0] << 8) | b[1]);
  71
  72     if((b[0] & 0xFE) == 0xFC) /* Handle ULAs */
  73       return IPV6_SCOPE_UNIQUELOCAL;
  74     switch(w & 0xFFC0) {
  75     case 0xFE80:
  76       return IPV6_SCOPE_LINKLOCAL;
  77     case 0xFEC0:
  78       return IPV6_SCOPE_SITELOCAL;
  79     case 0x0000:
  80       w = b[1] | b[2] | b[3] | b[4] | b[5] | b[6] | b[7] | b[8] | b[9] |
  81           b[10] | b[11] | b[12] | b[13] | b[14];
  82       if(w || b[15] != 0x01)
  83         break;
  84       return IPV6_SCOPE_NODELOCAL;
  85     default:
  86       break;
  87     }
  88   }
  89   return IPV6_SCOPE_GLOBAL;
  90 }
  91 #endif
  92
  93 #if defined(HAVE_GETIFADDRS)
  94
  95 if2ip_result_t Curl_if2ip(int af,
  96 #ifdef ENABLE_IPV6
  97                           unsigned int remote_scope,
  98                           unsigned int local_scope_id,
  99 #endif
 100                           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 #if defined(ENABLE_IPV6) && \
 107     !defined(HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID)
 108   (void) local_scope_id;
 109 #endif
 110
 111   if(getifaddrs(&head) >= 0) {
 112     for(iface = head; iface != NULL; iface = iface->ifa_next) {
 113       if(iface->ifa_addr) {
 114         if(iface->ifa_addr->sa_family == af) {
 115           if(strcasecompare(iface->ifa_name, interf)) {
 116             void *addr;
 117             const char *ip;
 118             char scope[12] = "";
 119             char ipstr[64];
 120 #ifdef ENABLE_IPV6
 121             if(af == AF_INET6) {
 122 #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID
 123               unsigned int scopeid = 0;
 124 #endif
 125               unsigned int ifscope = Curl_ipv6_scope(iface->ifa_addr);
 126
 127               if(ifscope != remote_scope) {
 128                 /* We are interested only in interface addresses whose scope
 129                    matches the remote address we want to connect to: global
 130                    for global, link-local for link-local, etc... */
 131                 if(res == IF2IP_NOT_FOUND)
 132                   res = IF2IP_AF_NOT_SUPPORTED;
 133                 continue;
 134               }
 135
 136               addr =
 137                 &((struct sockaddr_in6 *)(void *)iface->ifa_addr)->sin6_addr;
 138 #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID
 139               /* Include the scope of this interface as part of the address */
 140               scopeid = ((struct sockaddr_in6 *)(void *)iface->ifa_addr)
 141                             ->sin6_scope_id;
 142
 143               /* If given, scope id should match. */
 144               if(local_scope_id && scopeid != local_scope_id) {
 145                 if(res == IF2IP_NOT_FOUND)
 146                   res = IF2IP_AF_NOT_SUPPORTED;
 147
 148                 continue;
 149               }
 150
 151               if(scopeid)
 152                 msnprintf(scope, sizeof(scope), "%%%u", scopeid);
 153 #endif
 154             }
 155             else
 156 #endif
 157               addr =
 158                 &((struct sockaddr_in *)(void *)iface->ifa_addr)->sin_addr;
 159             res = IF2IP_FOUND;
 160             ip = Curl_inet_ntop(af, addr, ipstr, sizeof(ipstr));
 161             msnprintf(buf, buf_size, "%s%s", ip, scope);
 162             break;
 163           }
 164         }
 165         else if((res == IF2IP_NOT_FOUND) &&
 166                 strcasecompare(iface->ifa_name, interf)) {
 167           res = IF2IP_AF_NOT_SUPPORTED;
 168         }
 169       }
 170     }
 171
 172     freeifaddrs(head);
 173   }
 174
 175   return res;
 176 }
 177
 178 #elif defined(HAVE_IOCTL_SIOCGIFADDR)
 179
 180 if2ip_result_t Curl_if2ip(int af,
 181 #ifdef ENABLE_IPV6
 182                           unsigned int remote_scope,
 183                           unsigned int local_scope_id,
 184 #endif
 185                           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 #ifdef ENABLE_IPV6
 196   (void)remote_scope;
 197   (void)local_scope_id;
 198 #endif
 199
 200   if(!interf || (af != AF_INET))
 201     return IF2IP_NOT_FOUND;
 202
 203   len = strlen(interf);
 204   if(len >= sizeof(req.ifr_name))
 205     return IF2IP_NOT_FOUND;
 206
 207   dummy = socket(AF_INET, SOCK_STREAM, 0);
 208   if(CURL_SOCKET_BAD == dummy)
 209     return IF2IP_NOT_FOUND;
 210
 211   memset(&req, 0, sizeof(req));
 212   memcpy(req.ifr_name, interf, len + 1);
 213   req.ifr_addr.sa_family = AF_INET;
 214
 215   if(ioctl(dummy, SIOCGIFADDR, &req) < 0) {
 216     sclose(dummy);
 217     /* With SIOCGIFADDR, we cannot tell the difference between an interface
 218        that does not exist and an interface that has no address of the
 219        correct family. Assume the interface does not exist */
 220     return IF2IP_NOT_FOUND;
 221   }
 222
 223   s = (struct sockaddr_in *)(void *)&req.ifr_addr;
 224   memcpy(&in, &s->sin_addr, sizeof(in));
 225   r = Curl_inet_ntop(s->sin_family, &in, buf, buf_size);
 226
 227   sclose(dummy);
 228   if(!r)
 229     return IF2IP_NOT_FOUND;
 230   return IF2IP_FOUND;
 231 }
 232
 233 #else
 234
 235 if2ip_result_t Curl_if2ip(int af,
 236 #ifdef ENABLE_IPV6
 237                           unsigned int remote_scope,
 238                           unsigned int local_scope_id,
 239 #endif
 240                           const char *interf,
 241                           char *buf, int buf_size)
 242 {
 243     (void) af;
 244 #ifdef ENABLE_IPV6
 245     (void) remote_scope;
 246     (void) local_scope_id;
 247 #endif
 248     (void) interf;
 249     (void) buf;
 250     (void) buf_size;
 251     return IF2IP_NOT_FOUND;
 252 }
 253
 254 #endif