glibc/sunrpc/get_myaddr.c
2011-04-16 21:59:36 -04:00

104 lines
3.2 KiB
C

/*
* get_myaddress.c
*
* Get client's IP address via ioctl. This avoids using the yellowpages.
* Copyright (c) 2010, Oracle America, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
* * Neither the name of the "Oracle America, Inc." nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <rpc/types.h>
#include <rpc/clnt.h>
#include <rpc/pmap_prot.h>
#include <sys/socket.h>
#include <stdio.h>
#include <unistd.h>
#include <libintl.h>
#include <net/if.h>
#include <ifaddrs.h>
#include <sys/ioctl.h>
/* Order of following two #includes reversed by roland@gnu */
#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.
*/
void
get_myaddress (struct sockaddr_in *addr)
{
struct ifaddrs *ifa;
if (getifaddrs (&ifa) != 0)
{
perror ("get_myaddress: getifaddrs");
exit (1);
}
int loopback = 0;
struct ifaddrs *run;
again:
run = ifa;
while (run != NULL)
{
if ((run->ifa_flags & IFF_UP)
&& run->ifa_addr != NULL
&& run->ifa_addr->sa_family == AF_INET
&& (!(run->ifa_flags & IFF_LOOPBACK)
|| (loopback == 1 && (run->ifa_flags & IFF_LOOPBACK))))
{
*addr = *((struct sockaddr_in *) run->ifa_addr);
addr->sin_port = htons (PMAPPORT);
goto out;
}
run = run->ifa_next;
}
if (loopback == 0)
{
loopback = 1;
goto again;
}
out:
freeifaddrs (ifa);
/* The function is horribly specified. It does not return any error
if no interface is up. Probably this won't happen (at least
loopback is there) but still... */
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (get_myaddress)
#else
libc_hidden_nolink (get_myaddress, GLIBC_2_0)
#endif