sunrpc/get_myaddr.c

   1 /* @(#)get_myaddress.c  2.1 88/07/29 4.0 RPCSRC */
   2 /*
   3  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   4  * unrestricted use provided that this legend is included on all tape
   5  * media and as a part of the software program in whole or part.  Users
   6  * may copy or modify Sun RPC without charge, but are not authorized
   7  * to license or distribute it to anyone else except as part of a product or
   8  * program developed by the user.
   9  *
  10  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  11  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  12  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  13  *
  14  * Sun RPC is provided with no support and without any obligation on the
  15  * part of Sun Microsystems, Inc. to assist in its use, correction,
  16  * modification or enhancement.
  17  *
  18  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  19  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  20  * OR ANY PART THEREOF.
  21  *
  22  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  23  * or profits or other special, indirect and consequential damages, even if
  24  * Sun has been advised of the possibility of such damages.
  25  *
  26  * Sun Microsystems, Inc.
  27  * 2550 Garcia Avenue
  28  * Mountain View, California  94043
  29  */
  30 #if !defined(lint) && defined(SCCSIDS)
  31 static char sccsid[] = "@(#)get_myaddress.c 1.4 87/08/11 Copyr 1984 Sun Micro";
  32 #endif
  33
  34 /*
  35  * get_myaddress.c
  36  *
  37  * Get client's IP address via ioctl.  This avoids using the yellowpages.
  38  * Copyright (C) 1984, Sun Microsystems, Inc.
  39  */
  40
  41 #include <rpc/types.h>
  42 #include <rpc/pmap_prot.h>
  43 #include <sys/socket.h>
  44 #include <stdio.h>
  45 #undef   _POSIX_SOURCE          /* Ultrix <sys/param.h> needs --roland@gnu */
  46 #include <sys/param.h>          /* Ultrix needs before net/if --roland@gnu */
  47 #include <net/if.h>
  48 #include <sys/ioctl.h>
  49 /* Order of following two #includes reversed by roland@gnu */
  50 #include <netinet/in.h>
  51 #include <arpa/inet.h>
  52
  53 /*
  54  * don't use gethostbyname, which would invoke yellow pages
  55  */
  56 get_myaddress(addr)
  57         struct sockaddr_in *addr;
  58 {
  59         int s;
  60         char buf[BUFSIZ];
  61         struct ifconf ifc;
  62         struct ifreq ifreq, *ifr;
  63         int len;
  64
  65         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
  66             perror("get_myaddress: socket");
  67             exit(1);
  68         }
  69         ifc.ifc_len = sizeof (buf);
  70         ifc.ifc_buf = buf;
  71         if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {
  72                 perror("get_myaddress: ioctl (get interface configuration)");
  73                 exit(1);
  74         }
  75         ifr = ifc.ifc_req;
  76         for (len = ifc.ifc_len; len; len -= sizeof ifreq) {
  77                 ifreq = *ifr;
  78                 if (ioctl(s, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
  79                         perror("get_myaddress: ioctl");
  80                         exit(1);
  81                 }
  82                 if ((ifreq.ifr_flags & IFF_UP) &&
  83                     ifr->ifr_addr.sa_family == AF_INET) {
  84                         *addr = *((struct sockaddr_in *)&ifr->ifr_addr);
  85                         addr->sin_port = htons(PMAPPORT);
  86                         break;
  87                 }
  88                 ifr++;
  89         }
  90         (void) close(s);
  91 }