dhcpcd/ipv4ll.c
2008-01-21 21:19:53 +00:00

71 lines
2.2 KiB
C

/*
* dhcpcd - DHCP client daemon
* Copyright 2006-2008 Roy Marples <roy@marples.name>
* All rights reserved
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 <errno.h>
#include <stdlib.h>
#include "config.h"
#include "arp.h"
#include "ipv4ll.h"
#ifdef ENABLE_IPV4LL
#ifndef ENABLE_ARP
# error IPV4LL requires ARP
#endif
#define IPV4LL_LEASETIME 20
int ipv4ll_get_address (interface_t *iface, dhcp_t *dhcp) {
struct in_addr addr;
for (;;) {
addr.s_addr = htonl (LINKLOCAL_ADDR |
(((uint32_t) abs ((int) random ())
% 0xFD00) + 0x0100));
errno = 0;
if (! arp_claim (iface, addr))
break;
/* Our ARP may have been interrupted */
if (errno)
return (-1);
}
dhcp->address.s_addr = addr.s_addr;
dhcp->netmask.s_addr = htonl (LINKLOCAL_MASK);
dhcp->broadcast.s_addr = htonl (LINKLOCAL_BRDC);
/* Finally configure some DHCP like lease times */
dhcp->leasetime = IPV4LL_LEASETIME;
dhcp->renewaltime = (dhcp->leasetime * 0.5);
dhcp->rebindtime = (dhcp->leasetime * 0.875);
return (0);
}
#endif