busybox/networking/udhcp/socket.c

112 lines
3.1 KiB
C

/* vi: set sw=4 ts=4: */
/*
* socket.c -- DHCP server client/server socket creation
*
* udhcp client/server
* Copyright (C) 1999 Matthew Ramsay <matthewr@moreton.com.au>
* Chris Trew <ctrew@moreton.com.au>
*
* Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <net/if.h>
#include <features.h>
#if (defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1) || defined _NEWLIB_VERSION
#include <netpacket/packet.h>
#include <net/ethernet.h>
#else
#include <asm/types.h>
#include <linux/if_packet.h>
#include <linux/if_ether.h>
#endif
#include "common.h"
int FAST_FUNC udhcp_read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t *arp)
{
int fd;
struct ifreq ifr;
struct sockaddr_in *our_ip;
memset(&ifr, 0, sizeof(ifr));
fd = xsocket(AF_INET, SOCK_RAW, IPPROTO_RAW);
ifr.ifr_addr.sa_family = AF_INET;
strncpy_IFNAMSIZ(ifr.ifr_name, interface);
if (addr) {
if (ioctl_or_perror(fd, SIOCGIFADDR, &ifr,
"is interface %s up and configured?", interface)
) {
close(fd);
return -1;
}
our_ip = (struct sockaddr_in *) &ifr.ifr_addr;
*addr = our_ip->sin_addr.s_addr;
DEBUG("%s (our ip) = %s", ifr.ifr_name, inet_ntoa(our_ip->sin_addr));
}
if (ifindex) {
if (ioctl_or_warn(fd, SIOCGIFINDEX, &ifr) != 0) {
close(fd);
return -1;
}
DEBUG("adapter index %d", ifr.ifr_ifindex);
*ifindex = ifr.ifr_ifindex;
}
if (arp) {
if (ioctl_or_warn(fd, SIOCGIFHWADDR, &ifr) != 0) {
close(fd);
return -1;
}
memcpy(arp, ifr.ifr_hwaddr.sa_data, 6);
DEBUG("adapter hardware address %02x:%02x:%02x:%02x:%02x:%02x",
arp[0], arp[1], arp[2], arp[3], arp[4], arp[5]);
}
close(fd);
return 0;
}
/* 1. None of the callers expects it to ever fail */
/* 2. ip was always INADDR_ANY */
int FAST_FUNC udhcp_listen_socket(/*uint32_t ip,*/ int port, const char *inf)
{
int fd;
struct sockaddr_in addr;
DEBUG("Opening listen socket on *:%d %s", port, inf);
fd = xsocket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
setsockopt_reuseaddr(fd);
if (setsockopt_broadcast(fd) == -1)
bb_perror_msg_and_die("SO_BROADCAST");
/* NB: bug 1032 says this doesn't work on ethernet aliases (ethN:M) */
if (setsockopt_bindtodevice(fd, inf))
xfunc_die(); /* warning is already printed */
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
/* addr.sin_addr.s_addr = ip; - all-zeros is INADDR_ANY */
xbind(fd, (struct sockaddr *)&addr, sizeof(addr));
return fd;
}