hush/networking/udhcp/socket.c
Denis Vlasenko 48237b0c88 introduce setsockopt_reuseaddr(int fd), setsockopt_broadcast(int fd),
use them where appropriate. 200 bytes saved
2006-11-22 23:22:06 +00:00

131 lines
3.2 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 (__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 read_interface(char *interface, int *ifindex, uint32_t *addr, uint8_t *arp)
{
int fd;
struct ifreq ifr;
struct sockaddr_in *our_ip;
memset(&ifr, 0, sizeof(struct ifreq));
fd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
if (fd < 0) {
bb_perror_msg("socket failed");
return -1;
}
ifr.ifr_addr.sa_family = AF_INET;
strcpy(ifr.ifr_name, interface);
if (addr) {
if (ioctl(fd, SIOCGIFADDR, &ifr) == 0) {
bb_perror_msg("SIOCGIFADDR failed, is the interface up and configured?");
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(fd, SIOCGIFINDEX, &ifr) == 0) {
bb_perror_msg("SIOCGIFINDEX failed");
close(fd);
return -1;
}
DEBUG("adapter index %d", ifr.ifr_ifindex);
*ifindex = ifr.ifr_ifindex;
}
if (arp) {
if (ioctl(fd, SIOCGIFHWADDR, &ifr) != 0) {
bb_perror_msg("SIOCGIFHWADDR failed");
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]);
}
return 0;
}
int listen_socket(uint32_t ip, int port, char *inf)
{
struct ifreq interface;
int fd;
struct sockaddr_in addr;
DEBUG("Opening listen socket on 0x%08x:%d %s", ip, port, inf);
fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (fd < 0) {
bb_perror_msg("socket");
return -1;
}
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
addr.sin_addr.s_addr = ip;
if (setsockopt_reuseaddr(fd) == -1) {
close(fd);
return -1;
}
if (setsockopt_broadcast(fd) == -1) {
close(fd);
return -1;
}
strncpy(interface.ifr_name, inf, IFNAMSIZ);
if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, (char *)&interface, sizeof(interface)) < 0) {
close(fd);
return -1;
}
if (bind(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr)) == -1) {
close(fd);
return -1;
}
return fd;
}