aboutsummaryrefslogtreecommitdiff
path: root/networking/udhcp/socket.c
blob: 21a0585452d1d66dee735048560aa80d51a9b34c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
/* 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 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 = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
	if (fd < 0) {
		bb_perror_msg("socket failed");
		return -1;
	}

	ifr.ifr_addr.sa_family = AF_INET;
	strncpy(ifr.ifr_name, interface, sizeof(ifr.ifr_name));
	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]);
	}

	return 0;
}


int listen_socket(uint32_t ip, int port, const char *inf)
{
	struct ifreq interface;
	int fd;
	struct sockaddr_in addr;

	DEBUG("Opening listen socket on 0x%08x:%d %s", ip, port, inf);
	fd = xsocket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);

	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, &interface, sizeof(interface)) < 0) {
		close(fd);
		return -1;
	}

	if (bind(fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
		close(fd);
		return -1;
	}

	return fd;
}