4 * Copyright (C) 1999 Matthew Ramsay <matthewr@moreton.com.au>
5 * Chris Trew <ctrew@moreton.com.au>
7 * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28 #include <arpa/inet.h>
30 #include <netinet/in.h>
31 #include <sys/socket.h>
35 #include <sys/ioctl.h>
44 #include "serverpacket.h"
49 struct dhcpOfferedAddr *leases;
50 struct server_config_t server_config;
53 int udhcpd_main(int argc, char *argv[])
57 int server_socket = -1;
59 struct dhcpMessage packet;
61 unsigned char *server_id, *requested;
62 u_int32_t server_id_align, requested_align;
63 unsigned long timeout_end;
64 struct option_set *option;
65 struct dhcpOfferedAddr *lease;
68 unsigned long num_ips;
72 memset(&server_config, 0, sizeof(struct server_config_t));
75 read_config(DHCPD_CONF_FILE);
76 else read_config(argv[1]);
78 if ((option = find_option(server_config.options, DHCP_LEASE_TIME))) {
79 memcpy(&server_config.lease, option->data + 2, 4);
80 server_config.lease = ntohl(server_config.lease);
82 else server_config.lease = LEASE_TIME;
85 num_ips = ntohl(server_config.end) - ntohl(server_config.start);
86 if (server_config.max_leases > num_ips) {
87 LOG(LOG_ERR, "max_leases value (%lu) not sane, "
88 "setting to %lu instead",
89 server_config.max_leases, num_ips);
90 server_config.max_leases = num_ips;
93 leases = xcalloc(sizeof(struct dhcpOfferedAddr), server_config.max_leases);
94 read_leases(server_config.lease_file);
96 if (read_interface(server_config.interface, &server_config.ifindex,
97 &server_config.server, server_config.arp) < 0)
100 #ifndef CONFIG_FEATURE_UDHCP_DEBUG
101 background(server_config.pidfile);
104 udhcp_set_signal_pipe(0);
106 timeout_end = time(0) + server_config.auto_time;
107 while(1) { /* loop until universe collapses */
109 if (server_socket < 0)
110 if ((server_socket = listen_socket(INADDR_ANY, SERVER_PORT, server_config.interface)) < 0) {
111 LOG(LOG_ERR, "FATAL: couldn't create server socket, %m");
116 FD_SET(server_socket, &rfds);
117 FD_SET(udhcp_signal_pipe[0], &rfds);
118 if (server_config.auto_time) {
119 tv.tv_sec = timeout_end - time(0);
122 if (!server_config.auto_time || tv.tv_sec > 0) {
123 max_sock = server_socket > udhcp_signal_pipe[0] ? server_socket : udhcp_signal_pipe[0];
124 retval = select(max_sock + 1, &rfds, NULL, NULL,
125 server_config.auto_time ? &tv : NULL);
126 } else retval = 0; /* If we already timed out, fall through */
130 timeout_end = time(0) + server_config.auto_time;
132 } else if (retval < 0 && errno != EINTR) {
133 DEBUG(LOG_INFO, "error on select");
137 if (FD_ISSET(udhcp_signal_pipe[0], &rfds)) {
138 if (read(udhcp_signal_pipe[0], &sig, sizeof(sig)) < 0)
139 continue; /* probably just EINTR */
142 LOG(LOG_INFO, "Received a SIGUSR1");
144 /* why not just reset the timeout, eh */
145 timeout_end = time(0) + server_config.auto_time;
148 LOG(LOG_INFO, "Received a SIGTERM");
153 if ((bytes = get_packet(&packet, server_socket)) < 0) { /* this waits for a packet - idle */
154 if (bytes == -1 && errno != EINTR) {
155 DEBUG(LOG_INFO, "error on read, %m, reopening socket");
156 close(server_socket);
162 if ((state = get_option(&packet, DHCP_MESSAGE_TYPE)) == NULL) {
163 DEBUG(LOG_ERR, "couldn't get option from packet, ignoring");
167 /* ADDME: look for a static lease */
168 lease = find_lease_by_chaddr(packet.chaddr);
171 DEBUG(LOG_INFO,"received DISCOVER");
173 if (sendOffer(&packet) < 0) {
174 LOG(LOG_ERR, "send OFFER failed");
178 DEBUG(LOG_INFO, "received REQUEST");
180 requested = get_option(&packet, DHCP_REQUESTED_IP);
181 server_id = get_option(&packet, DHCP_SERVER_ID);
183 if (requested) memcpy(&requested_align, requested, 4);
184 if (server_id) memcpy(&server_id_align, server_id, 4);
186 if (lease) { /*ADDME: or static lease */
188 /* SELECTING State */
189 DEBUG(LOG_INFO, "server_id = %08x", ntohl(server_id_align));
190 if (server_id_align == server_config.server && requested &&
191 requested_align == lease->yiaddr) {
192 sendACK(&packet, lease->yiaddr);
196 /* INIT-REBOOT State */
197 if (lease->yiaddr == requested_align)
198 sendACK(&packet, lease->yiaddr);
199 else sendNAK(&packet);
201 /* RENEWING or REBINDING State */
202 if (lease->yiaddr == packet.ciaddr)
203 sendACK(&packet, lease->yiaddr);
205 /* don't know what to do!!!! */
211 /* what to do if we have no record of the client */
212 } else if (server_id) {
213 /* SELECTING State */
215 } else if (requested) {
216 /* INIT-REBOOT State */
217 if ((lease = find_lease_by_yiaddr(requested_align))) {
218 if (lease_expired(lease)) {
219 /* probably best if we drop this lease */
220 memset(lease->chaddr, 0, 16);
221 /* make some contention for this address */
222 } else sendNAK(&packet);
223 } else if (requested_align < server_config.start ||
224 requested_align > server_config.end) {
226 } /* else remain silent */
229 /* RENEWING or REBINDING State */
233 DEBUG(LOG_INFO,"received DECLINE");
235 memset(lease->chaddr, 0, 16);
236 lease->expires = time(0) + server_config.decline_time;
240 DEBUG(LOG_INFO,"received RELEASE");
241 if (lease) lease->expires = time(0);
244 DEBUG(LOG_INFO,"received INFORM");
245 send_inform(&packet);
248 LOG(LOG_WARNING, "unsupported DHCP message (%02x) -- ignoring", state[0]);