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/*
* Sun RPC is a product of Sun Microsystems, Inc. and is provided for
* unrestricted use provided that this legend is included on all tape
* media and as a part of the software program in whole or part. Users
* may copy or modify Sun RPC without charge, but are not authorized
* to license or distribute it to anyone else except as part of a product or
* program developed by the user.
*
* SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
* WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
* PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
*
* Sun RPC is provided with no support and without any obligation on the
* part of Sun Microsystems, Inc. to assist in its use, correction,
* modification or enhancement.
*
* SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
* INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
* OR ANY PART THEREOF.
*
* In no event will Sun Microsystems, Inc. be liable for any lost revenue
* or profits or other special, indirect and consequential damages, even if
* Sun has been advised of the possibility of such damages.
*
* Sun Microsystems, Inc.
* 2550 Garcia Avenue
* Mountain View, California 94043
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: get_myaddress.c,v 1.7 1997/01/22 18:50:40 deraadt Exp $";
#endif /* LIBC_SCCS and not lint */
/*
* get_myaddress.c
*
* Get client's IP address via ioctl. This avoids using the yellowpages.
* Copyright (C) 1984, Sun Microsystems, Inc.
*/
#include <rpc/types.h>
#include <rpc/xdr.h>
#include <rpc/pmap_prot.h>
#include <sys/socket.h>
#include <stdio.h>
#include <stdlib.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <arpa/inet.h>
/*
* don't use gethostbyname, which would invoke yellow pages
*
* Avoid loopback interfaces. We return information from a loopback
* interface only if there are no other possible interfaces.
*/
int
get_myaddress(addr)
struct sockaddr_in *addr;
{
int s;
char *inbuf = NULL;
struct ifconf ifc;
struct ifreq ifreq, *ifr;
int len, inbuflen = 8192, slop;
int loopback = 0, gotit = 0;
if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
return (-1);
}
while (1) {
ifc.ifc_len = inbuflen;
ifc.ifc_buf = inbuf = realloc(inbuf, inbuflen);
if (inbuf == NULL) {
close(s);
return (-1);
}
if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {
(void) close(s);
free(inbuf);
return (-1);
}
if (ifc.ifc_len + sizeof(ifreq) < inbuflen)
break;
inbuflen *= 2;
}
again:
ifr = ifc.ifc_req;
for (len = ifc.ifc_len; len; len -= sizeof ifreq) {
ifreq = *ifr;
if (ioctl(s, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
(void) close(s);
free(inbuf);
return (-1);
}
if ((ifreq.ifr_flags & IFF_UP) &&
ifr->ifr_addr.sa_family == AF_INET &&
(loopback == 1 && (ifreq.ifr_flags & IFF_LOOPBACK))) {
*addr = *((struct sockaddr_in *)&ifr->ifr_addr);
addr->sin_port = htons(PMAPPORT);
gotit = 1;
break;
}
/*
* Deal with variable length addresses
*/
slop = ifr->ifr_addr.sa_len - sizeof (struct sockaddr);
if (slop > 0) {
ifr = (struct ifreq *) ((caddr_t)ifr + slop);
len -= slop;
}
ifr++;
}
if (gotit == 0 && loopback == 0) {
loopback = 1;
goto again;
}
(void) close(s);
free (inbuf);
return (0);
}
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