1/*
2 * socket.c -- DHCP server client/server socket creation
3 *
4 * udhcp client/server
5 * Copyright (C) 1999 Matthew Ramsay <matthewr@moreton.com.au>
6 *			Chris Trew <ctrew@moreton.com.au>
7 *
8 * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25#include <sys/types.h>
26#include <sys/socket.h>
27#include <sys/ioctl.h>
28#include <netinet/in.h>
29#include <unistd.h>
30#include <string.h>
31#include <arpa/inet.h>
32#include <net/if.h>
33#include <errno.h>
34#include <features.h>
35#if __GLIBC__ >=2 && __GLIBC_MINOR >= 1
36#include <netpacket/packet.h>
37#include <net/ethernet.h>
38#else
39#include <asm/types.h>
40#include <linux/if_packet.h>
41#include <linux/if_ether.h>
42#endif
43
44#include "debug.h"
45
46int read_interface(char *interface, int *ifindex, u_int32_t *addr, unsigned char *arp)
47{
48	int fd;
49	struct ifreq ifr;
50	struct sockaddr_in *our_ip;
51
52	memset(&ifr, 0, sizeof(struct ifreq));
53	if((fd = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)) >= 0) {
54		ifr.ifr_addr.sa_family = AF_INET;
55		strcpy(ifr.ifr_name, interface);
56
57		if (addr) {
58			if (ioctl(fd, SIOCGIFADDR, &ifr) == 0) {
59				our_ip = (struct sockaddr_in *) &ifr.ifr_addr;
60				*addr = our_ip->sin_addr.s_addr;
61				DEBUG(LOG_INFO, "%s (our ip) = %s", ifr.ifr_name, inet_ntoa(our_ip->sin_addr));
62			} else {
63				LOG(LOG_ERR, "SIOCGIFADDR failed, is the interface up and configured?: %s",
64						strerror(errno));
65				return -1;
66			}
67		}
68
69		if (ioctl(fd, SIOCGIFINDEX, &ifr) == 0) {
70			DEBUG(LOG_INFO, "adapter index %d", ifr.ifr_ifindex);
71			*ifindex = ifr.ifr_ifindex;
72		} else {
73			LOG(LOG_ERR, "SIOCGIFINDEX failed!: %s", strerror(errno));
74			return -1;
75		}
76		if (ioctl(fd, SIOCGIFHWADDR, &ifr) == 0) {
77			memcpy(arp, ifr.ifr_hwaddr.sa_data, 6);
78			DEBUG(LOG_INFO, "adapter hardware address %02x:%02x:%02x:%02x:%02x:%02x",
79				arp[0], arp[1], arp[2], arp[3], arp[4], arp[5]);
80		} else {
81			LOG(LOG_ERR, "SIOCGIFHWADDR failed!: %s", strerror(errno));
82			return -1;
83		}
84	} else {
85		LOG(LOG_ERR, "socket failed!: %s", strerror(errno));
86		return -1;
87	}
88	close(fd);
89	return 0;
90}
91
92
93int listen_socket(unsigned int ip, int port, char *inf)
94{
95	struct ifreq interface;
96	int fd;
97	struct sockaddr_in addr;
98	int n = 1;
99
100	DEBUG(LOG_INFO, "Opening listen socket on 0x%08x:%d %s\n", ip, port, inf);
101	if ((fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
102		DEBUG(LOG_ERR, "socket call failed: %s", strerror(errno));
103		return -1;
104	}
105
106	memset(&addr, 0, sizeof(addr));
107	addr.sin_family = AF_INET;
108	addr.sin_port = htons(port);
109	addr.sin_addr.s_addr = ip;
110
111	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *) &n, sizeof(n)) == -1) {
112		close(fd);
113		return -1;
114	}
115	if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, (char *) &n, sizeof(n)) == -1) {
116		close(fd);
117		return -1;
118	}
119
120	strncpy(interface.ifr_ifrn.ifrn_name, inf, IFNAMSIZ);
121	if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,(char *)&interface, sizeof(interface)) < 0) {
122		close(fd);
123		return -1;
124	}
125
126	if (bind(fd, (struct sockaddr *)&addr, sizeof(struct sockaddr)) == -1) {
127		close(fd);
128		return -1;
129	}
130
131	return fd;
132}
133
134
135int raw_socket(int ifindex)
136{
137	int fd;
138	struct sockaddr_ll sock;
139
140	DEBUG(LOG_INFO, "Opening raw socket on ifindex %d\n", ifindex);
141	if ((fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP))) < 0) {
142		DEBUG(LOG_ERR, "socket call failed: %s", strerror(errno));
143		return -1;
144	}
145
146	sock.sll_family = AF_PACKET;
147	sock.sll_protocol = htons(ETH_P_IP);
148	sock.sll_ifindex = ifindex;
149	if (bind(fd, (struct sockaddr *) &sock, sizeof(sock)) < 0) {
150		DEBUG(LOG_ERR, "bind call failed: %s", strerror(errno));
151		close(fd);
152		return -1;
153	}
154
155	return fd;
156}
157
158