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"
46 #include "signalpipe.h"
50 struct dhcpOfferedAddr *leases;
51 struct server_config_t server_config;
54 #ifdef COMBINED_BINARY
55 int udhcpd_main(int argc, char *argv[])
57 int main(int argc, char *argv[])
62 int server_socket = -1;
64 struct dhcpMessage packet;
66 uint8_t *server_id, *requested;
67 uint32_t server_id_align, requested_align;
68 unsigned long timeout_end;
69 struct option_set *option;
70 struct dhcpOfferedAddr *lease;
72 unsigned long num_ips;
74 memset(&server_config, 0, sizeof(struct server_config_t));
75 read_config(argc < 2 ? DHCPD_CONF_FILE : argv[1]);
77 /* Start the log, sanitize fd's, and write a pid file */
78 start_log_and_pid("udhcpd", server_config.pidfile);
80 if ((option = find_option(server_config.options, DHCP_LEASE_TIME))) {
81 memcpy(&server_config.lease, option->data + 2, 4);
82 server_config.lease = ntohl(server_config.lease);
84 else server_config.lease = LEASE_TIME;
87 num_ips = ntohl(server_config.end) - ntohl(server_config.start);
88 if (server_config.max_leases > num_ips) {
89 LOG(LOG_ERR, "max_leases value (%lu) not sane, "
90 "setting to %lu instead",
91 server_config.max_leases, num_ips);
92 server_config.max_leases = num_ips;
95 leases = xcalloc(server_config.max_leases, sizeof(struct dhcpOfferedAddr));
96 read_leases(server_config.lease_file);
98 if (read_interface(server_config.interface, &server_config.ifindex,
99 &server_config.server, server_config.arp) < 0)
103 background(server_config.pidfile); /* hold lock during fork. */
106 /* Setup the signal pipe */
109 timeout_end = time(0) + server_config.auto_time;
110 while(1) { /* loop until universe collapses */
112 if (server_socket < 0)
113 if ((server_socket = listen_socket(INADDR_ANY, SERVER_PORT, server_config.interface)) < 0) {
114 LOG(LOG_ERR, "FATAL: couldn't create server socket, %m");
118 max_sock = udhcp_sp_fd_set(&rfds, server_socket);
119 if (server_config.auto_time) {
120 tv.tv_sec = timeout_end - time(0);
123 if (!server_config.auto_time || tv.tv_sec > 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 switch (udhcp_sp_read(&rfds)) {
139 LOG(LOG_INFO, "Received a SIGUSR1");
141 /* why not just reset the timeout, eh */
142 timeout_end = time(0) + server_config.auto_time;
145 LOG(LOG_INFO, "Received a SIGTERM");
147 case 0: break; /* no signal */
148 default: continue; /* signal or error (probably EINTR) */
151 if ((bytes = get_packet(&packet, server_socket)) < 0) { /* this waits for a packet - idle */
152 if (bytes == -1 && errno != EINTR) {
153 DEBUG(LOG_INFO, "error on read, %m, reopening socket");
154 close(server_socket);
160 if ((state = get_option(&packet, DHCP_MESSAGE_TYPE)) == NULL) {
161 DEBUG(LOG_ERR, "couldn't get option from packet, ignoring");
165 /* ADDME: look for a static lease */
166 lease = find_lease_by_chaddr(packet.chaddr);
169 DEBUG(LOG_INFO,"received DISCOVER");
171 if (sendOffer(&packet) < 0) {
172 LOG(LOG_ERR, "send OFFER failed");
176 DEBUG(LOG_INFO, "received REQUEST");
178 requested = get_option(&packet, DHCP_REQUESTED_IP);
179 server_id = get_option(&packet, DHCP_SERVER_ID);
181 if (requested) memcpy(&requested_align, requested, 4);
182 if (server_id) memcpy(&server_id_align, server_id, 4);
184 if (lease) { /*ADDME: or static lease */
186 /* SELECTING State */
187 DEBUG(LOG_INFO, "server_id = %08x", ntohl(server_id_align));
188 if (server_id_align == server_config.server && requested &&
189 requested_align == lease->yiaddr) {
190 sendACK(&packet, lease->yiaddr);
194 /* INIT-REBOOT State */
195 if (lease->yiaddr == requested_align)
196 sendACK(&packet, lease->yiaddr);
197 else sendNAK(&packet);
199 /* RENEWING or REBINDING State */
200 if (lease->yiaddr == packet.ciaddr)
201 sendACK(&packet, lease->yiaddr);
203 /* don't know what to do!!!! */
209 /* what to do if we have no record of the client */
210 } else if (server_id) {
211 /* SELECTING State */
213 } else if (requested) {
214 /* INIT-REBOOT State */
215 if ((lease = find_lease_by_yiaddr(requested_align))) {
216 if (lease_expired(lease)) {
217 /* probably best if we drop this lease */
218 memset(lease->chaddr, 0, 16);
219 /* make some contention for this address */
220 } else sendNAK(&packet);
221 } else if (requested_align < server_config.start ||
222 requested_align > server_config.end) {
224 } /* else remain silent */
227 /* RENEWING or REBINDING State */
231 DEBUG(LOG_INFO,"received DECLINE");
233 memset(lease->chaddr, 0, 16);
234 lease->expires = time(0) + server_config.decline_time;
238 DEBUG(LOG_INFO,"received RELEASE");
239 if (lease) lease->expires = time(0);
242 DEBUG(LOG_INFO,"received INFORM");
243 send_inform(&packet);
246 LOG(LOG_WARNING, "unsupported DHCP message (%02x) -- ignoring", state[0]);