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/*
* Check if an address belongs to the local system. Adapted from:
*
* @(#)pmap_svc.c 1.32 91/03/11 Copyright 1984,1990 Sun Microsystems, Inc.
* @(#)get_myaddress.c 2.1 88/07/29 4.0 RPCSRC.
*/
/*
* 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 or with the express written consent of
* Sun Microsystems, Inc.
*
* 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
*/
#ifndef lint
static char sccsid[] = "@(#) from_local.c 1.2 93/11/16 21:50:02";
#endif
#ifdef TEST
#undef perror
#endif
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <syslog.h>
#ifndef TRUE
#define TRUE 1
#define FALSE 0
#endif
/* How many interfaces could there be on a computer? */
#define MAX_LOCAL 16
static int num_local = -1;
static struct in_addr addrs[MAX_LOCAL];
/* find_local - find all IP addresses for this host */
find_local()
{
struct ifconf ifc;
struct ifreq ifreq;
struct ifreq *ifr;
struct ifreq *the_end;
int sock;
char buf[MAX_LOCAL * sizeof(struct ifreq)];
/* Get list of network interfaces. */
if ((sock = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
perror("socket");
return (0);
}
ifc.ifc_len = sizeof(buf);
ifc.ifc_buf = buf;
if (ioctl(sock, SIOCGIFCONF, (char *) &ifc) < 0) {
perror("SIOCGIFCONF");
(void) close(sock);
return (0);
}
/* Get IP address of each active IP network interface. */
the_end = (struct ifreq *) (ifc.ifc_buf + ifc.ifc_len);
num_local = 0;
for (ifr = ifc.ifc_req; ifr < the_end; ifr++) {
if (ifr->ifr_addr.sa_family == AF_INET) { /* IP net interface */
ifreq = *ifr;
if (ioctl(sock, SIOCGIFFLAGS, (char *) &ifreq) < 0) {
perror("SIOCGIFFLAGS");
} else if (ifreq.ifr_flags & IFF_UP) { /* active interface */
if (ioctl(sock, SIOCGIFADDR, (char *) &ifreq) < 0) {
perror("SIOCGIFADDR");
} else {
addrs[num_local++] = ((struct sockaddr_in *)
& ifreq.ifr_addr)->sin_addr;
}
}
}
if (num_local >= MAX_LOCAL)
break;
/* Support for variable-length addresses. */
ifr = (struct ifreq *) ((caddr_t) ifr
+ ifr->ifr_addr.sa_len - sizeof(struct sockaddr));
}
(void) close(sock);
return (num_local);
}
/* from_local - determine whether request comes from the local system */
from_local(addr)
struct sockaddr_in *addr;
{
int i;
if (num_local == -1 && find_local() == 0)
syslog(LOG_ERR, "cannot find any active local network interfaces");
for (i = 0; i < num_local; i++) {
if (memcmp((char *) &(addr->sin_addr), (char *) &(addrs[i]),
sizeof(struct in_addr)) == 0)
return (TRUE);
}
return (FALSE);
}
#ifdef TEST
main()
{
char *inet_ntoa();
int i;
find_local();
for (i = 0; i < num_local; i++)
printf("%s\n", inet_ntoa(addrs[i]));
}
#endif
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