rpc.subproj/get_myaddress.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
  26  * unrestricted use provided that this legend is included on all tape
  27  * media and as a part of the software program in whole or part.  Users
  28  * may copy or modify Sun RPC without charge, but are not authorized
  29  * to license or distribute it to anyone else except as part of a product or
  30  * program developed by the user.
  31  *
  32  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  33  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  34  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  35  *
  36  * Sun RPC is provided with no support and without any obligation on the
  37  * part of Sun Microsystems, Inc. to assist in its use, correction,
  38  * modification or enhancement.
  39  *
  40  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  41  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  42  * OR ANY PART THEREOF.
  43  *
  44  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  45  * or profits or other special, indirect and consequential damages, even if
  46  * Sun has been advised of the possibility of such damages.
  47  *
  48  * Sun Microsystems, Inc.
  49  * 2550 Garcia Avenue
  50  * Mountain View, California  94043
  51  */
  52
  53 #if defined(LIBC_SCCS) && !defined(lint)
  54 /*static char *sccsid = "from: @(#)get_myaddress.c 1.4 87/08/11 Copyr 1984 Sun Micro";*/
  55 /*static char *sccsid = "from: @(#)get_myaddress.c      2.1 88/07/29 4.0 RPCSRC";*/
  56 static char *rcsid = "$Id: get_myaddress.c,v 1.3 2000/08/03 20:25:14 ajn Exp $";
  57 #endif
  58
  59 /*
  60  * get_myaddress.c
  61  *
  62  * Get client's IP address via ioctl.  This avoids using the yellowpages.
  63  * Copyright (C) 1984, Sun Microsystems, Inc.
  64  *
  65  * Re-worked for 4.4BSD by Marc Majka at Apple.
  66  */
  67
  68 #include <rpc/types.h>
  69 #include <rpc/xdr.h>
  70 #include <rpc/pmap_prot.h>
  71 #include <sys/socket.h>
  72 #include <stdio.h>
  73 #include <unistd.h>
  74 #include <net/if.h>
  75 #include <sys/ioctl.h>
  76 #include <netinet/in.h>
  77 #include <arpa/inet.h>
  78
  79 int
  80 get_myaddress(struct sockaddr_in *addr)
  81 {
  82         struct ifconf ifc;
  83         struct ifreq *ifr;
  84         char buf[BUFSIZ];
  85         int offset, x, addrlen, s;
  86
  87         bzero(addr, sizeof(struct sockaddr_in));
  88         addr->sin_family = AF_INET;
  89
  90         s = socket(AF_INET, SOCK_DGRAM, 0);
  91
  92         if (s < 0)
  93         {
  94                 addr->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
  95                 return 0;
  96         }
  97
  98         ifc.ifc_len = sizeof(buf);
  99         ifc.ifc_buf = buf;
 100
 101         if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0)
 102         {
 103                 addr->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 104                 close(s);
 105                 return 0;
 106         }
 107
 108         addrlen = sizeof(struct ifreq) - IFNAMSIZ;
 109         offset = 0;
 110
 111         while (offset <= ifc.ifc_len)
 112         {
 113                 ifr = (struct ifreq *)(ifc.ifc_buf + offset);
 114                 offset += IFNAMSIZ;
 115                 if (ifr->ifr_addr.sa_len > addrlen) offset += ifr->ifr_addr.sa_len;
 116                 else offset += addrlen;
 117
 118                 if (ifr->ifr_addr.sa_family != AF_INET) continue;
 119                 if (ioctl(s, SIOCGIFFLAGS, ifr) < 0) continue;
 120
 121                 x = ((struct sockaddr_in *)&(ifr->ifr_addr))->sin_addr.s_addr;
 122                 if
 123                 (
 124                         (ifr->ifr_flags & IFF_UP) &&
 125                         (!(ifr->ifr_flags & IFF_LOOPBACK)) &&
 126                         (x != 0) &&
 127                         (x != -1)
 128                 )
 129                 {
 130                         addr->sin_addr.s_addr = x;
 131                         close(s);
 132                         return 0;
 133                 }
 134         }
 135
 136         close(s);
 137         addr->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 138         return 0;
 139 }