+/* vi: set sw=4 ts=4: */
/* dhcpd.c
*
* udhcp Server
*
* 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.
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
-#include <fcntl.h>
-#include <string.h>
-#include <stdlib.h>
-#include <sys/wait.h>
-#include <sys/stat.h>
-#include <arpa/inet.h>
-#include <netdb.h>
-#include <netinet/in.h>
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <unistd.h>
-#include <signal.h>
-#include <errno.h>
-#include <sys/ioctl.h>
-#include <time.h>
-#include <sys/time.h>
-
-#include "debug.h"
+#include <syslog.h>
+#include "common.h"
#include "dhcpd.h"
-#include "arpping.h"
-#include "socket.h"
#include "options.h"
-#include "files.h"
-#include "leases.h"
-#include "packet.h"
-#include "serverpacket.h"
-#include "pidfile.h"
/* globals */
struct dhcpOfferedAddr *leases;
-struct server_config_t server_config;
-static int signal_pipe[2];
+/* struct server_config_t server_config is in bb_common_bufsiz1 */
-/* Exit and cleanup */
-static void exit_server(int retval)
-{
- pidfile_delete(server_config.pidfile);
- CLOSE_LOG();
- exit(retval);
-}
-
-/* Signal handler */
-static void signal_handler(int sig)
+int udhcpd_main(int argc, char **argv);
+int udhcpd_main(int argc, char **argv)
{
- if (send(signal_pipe[1], &sig, sizeof(sig), MSG_DONTWAIT) < 0) {
- LOG(LOG_ERR, "Could not send signal: %s",
- strerror(errno));
- }
-}
-
-
-#ifdef COMBINED_BINARY
-int udhcpd_main(int argc, char *argv[])
-#else
-int main(int argc, char *argv[])
-#endif
-{
fd_set rfds;
struct timeval tv;
- int server_socket = -1;
- int bytes, retval;
+ int server_socket = -1, bytes, retval, max_sock;
struct dhcpMessage packet;
- unsigned char *state;
- unsigned char *server_id, *requested;
- u_int32_t server_id_align, requested_align;
- unsigned long timeout_end;
+ uint8_t *state, *server_id, *requested;
+ uint32_t server_id_align, requested_align, static_lease_ip;
+ unsigned timeout_end;
+ unsigned num_ips;
+ unsigned opt;
struct option_set *option;
- struct dhcpOfferedAddr *lease;
- int pid_fd;
- int max_sock;
- int sig;
- unsigned long num_ips;
-
- OPEN_LOG("udhcpd");
- LOG(LOG_INFO, "udhcp server (v%s) started", VERSION);
-
- memset(&server_config, 0, sizeof(struct server_config_t));
-
- if (argc < 2)
- read_config(DHCPD_CONF_FILE);
- else read_config(argv[1]);
-
- pid_fd = pidfile_acquire(server_config.pidfile);
- pidfile_write_release(pid_fd);
-
- if ((option = find_option(server_config.options, DHCP_LEASE_TIME))) {
+ struct dhcpOfferedAddr *lease, static_lease;
+
+ opt = getopt32(argv, "fS");
+ argv += optind;
+
+ if (!(opt & 1)) { /* no -f */
+ bb_daemonize_or_rexec(0, argv);
+ logmode &= ~LOGMODE_STDIO;
+ }
+
+ if (opt & 2) { /* -S */
+ openlog(applet_name, LOG_PID, LOG_LOCAL0);
+ logmode |= LOGMODE_SYSLOG;
+ }
+
+ /* Would rather not do read_config before daemonization -
+ * otherwise NOMMU machines will parse config twice */
+ read_config(argv[0] ? argv[0] : DHCPD_CONF_FILE);
+
+ /* Make sure fd 0,1,2 are open */
+ bb_sanitize_stdio();
+ /* Equivalent of doing a fflush after every \n */
+ setlinebuf(stdout);
+
+ /* Create pidfile */
+ write_pidfile(server_config.pidfile);
+ /* if (!..) bb_perror_msg("cannot create pidfile %s", pidfile); */
+
+ bb_info_msg("%s (v%s) started", applet_name, BB_VER);
+
+ option = find_option(server_config.options, DHCP_LEASE_TIME);
+ server_config.lease = LEASE_TIME;
+ if (option) {
memcpy(&server_config.lease, option->data + 2, 4);
server_config.lease = ntohl(server_config.lease);
}
- else server_config.lease = LEASE_TIME;
-
+
/* Sanity check */
- num_ips = ntohl(server_config.end) - ntohl(server_config.start);
+ num_ips = server_config.end_ip - server_config.start_ip + 1;
if (server_config.max_leases > num_ips) {
- LOG(LOG_ERR, "max_leases value (%lu) not sane, setting to %lu instead",
- server_config.max_leases, num_ips);
+ bb_error_msg("max_leases=%u is too big, setting to %u",
+ (unsigned)server_config.max_leases, num_ips);
server_config.max_leases = num_ips;
}
- leases = xmalloc(sizeof(struct dhcpOfferedAddr) * server_config.max_leases);
- memset(leases, 0, sizeof(struct dhcpOfferedAddr) * server_config.max_leases);
+ leases = xzalloc(server_config.max_leases * sizeof(*leases));
read_leases(server_config.lease_file);
if (read_interface(server_config.interface, &server_config.ifindex,
- &server_config.server, server_config.arp) < 0)
- exit_server(1);
-
-#ifndef DEBUGGING
- pid_fd = pidfile_acquire(server_config.pidfile); /* hold lock during fork. */
- if (daemon(0, 0) == -1) {
- perror("fork");
- exit_server(1);
+ &server_config.server, server_config.arp)) {
+ retval = 1;
+ goto ret;
}
- pidfile_write_release(pid_fd);
-#endif
-
- socketpair(AF_UNIX, SOCK_STREAM, 0, signal_pipe);
- signal(SIGUSR1, signal_handler);
- signal(SIGTERM, signal_handler);
+ /* Setup the signal pipe */
+ udhcp_sp_setup();
- timeout_end = time(0) + server_config.auto_time;
- while(1) { /* loop until universe collapses */
+ timeout_end = monotonic_sec() + server_config.auto_time;
+ while (1) { /* loop until universe collapses */
- if (server_socket < 0)
- if ((server_socket = listen_socket(INADDR_ANY, SERVER_PORT, server_config.interface)) < 0) {
- LOG(LOG_ERR, "FATAL: couldn't create server socket, %s", strerror(errno));
- exit_server(0);
- }
+ if (server_socket < 0) {
+ server_socket = listen_socket(/*INADDR_ANY,*/ SERVER_PORT,
+ server_config.interface);
+ }
- FD_ZERO(&rfds);
- FD_SET(server_socket, &rfds);
- FD_SET(signal_pipe[0], &rfds);
+ max_sock = udhcp_sp_fd_set(&rfds, server_socket);
if (server_config.auto_time) {
- tv.tv_sec = timeout_end - time(0);
+ tv.tv_sec = timeout_end - monotonic_sec();
tv.tv_usec = 0;
}
+ retval = 0;
if (!server_config.auto_time || tv.tv_sec > 0) {
- max_sock = server_socket > signal_pipe[0] ? server_socket : signal_pipe[0];
- retval = select(max_sock + 1, &rfds, NULL, NULL,
+ retval = select(max_sock + 1, &rfds, NULL, NULL,
server_config.auto_time ? &tv : NULL);
- } else retval = 0; /* If we already timed out, fall through */
-
+ }
if (retval == 0) {
write_leases();
- timeout_end = time(0) + server_config.auto_time;
+ timeout_end = monotonic_sec() + server_config.auto_time;
continue;
- } else if (retval < 0 && errno != EINTR) {
- DEBUG(LOG_INFO, "error on select");
+ }
+ if (retval < 0 && errno != EINTR) {
+ DEBUG("error on select");
continue;
}
-
- if (FD_ISSET(signal_pipe[0], &rfds)) {
- if (read(signal_pipe[0], &sig, sizeof(sig)) < 0)
- continue; /* probably just EINTR */
- switch (sig) {
- case SIGUSR1:
- LOG(LOG_INFO, "Received a SIGUSR1");
- write_leases();
- /* why not just reset the timeout, eh */
- timeout_end = time(0) + server_config.auto_time;
- continue;
- case SIGTERM:
- LOG(LOG_INFO, "Received a SIGTERM");
- exit_server(0);
- }
+
+ switch (udhcp_sp_read(&rfds)) {
+ case SIGUSR1:
+ bb_info_msg("Received a SIGUSR1");
+ write_leases();
+ /* why not just reset the timeout, eh */
+ timeout_end = monotonic_sec() + server_config.auto_time;
+ continue;
+ case SIGTERM:
+ bb_info_msg("Received a SIGTERM");
+ goto ret0;
+ case 0: break; /* no signal */
+ default: continue; /* signal or error (probably EINTR) */
}
- if ((bytes = get_packet(&packet, server_socket)) < 0) { /* this waits for a packet - idle */
+ bytes = udhcp_get_packet(&packet, server_socket); /* this waits for a packet - idle */
+ if (bytes < 0) {
if (bytes == -1 && errno != EINTR) {
- DEBUG(LOG_INFO, "error on read, %s, reopening socket", strerror(errno));
+ DEBUG("error on read, %s, reopening socket", strerror(errno));
close(server_socket);
server_socket = -1;
}
continue;
}
- if ((state = get_option(&packet, DHCP_MESSAGE_TYPE)) == NULL) {
- DEBUG(LOG_ERR, "couldn't get option from packet, ignoring");
+ state = get_option(&packet, DHCP_MESSAGE_TYPE);
+ if (state == NULL) {
+ bb_error_msg("cannot get option from packet, ignoring");
continue;
}
-
- /* ADDME: look for a static lease */
- lease = find_lease_by_chaddr(packet.chaddr);
+
+ /* Look for a static lease */
+ static_lease_ip = getIpByMac(server_config.static_leases, &packet.chaddr);
+
+ if (static_lease_ip) {
+ bb_info_msg("Found static lease: %x", static_lease_ip);
+
+ memcpy(&static_lease.chaddr, &packet.chaddr, 16);
+ static_lease.yiaddr = static_lease_ip;
+ static_lease.expires = 0;
+
+ lease = &static_lease;
+ } else {
+ lease = find_lease_by_chaddr(packet.chaddr);
+ }
+
switch (state[0]) {
case DHCPDISCOVER:
- DEBUG(LOG_INFO,"received DISCOVER");
-
+ DEBUG("Received DISCOVER");
+
if (sendOffer(&packet) < 0) {
- LOG(LOG_ERR, "send OFFER failed");
+ bb_error_msg("send OFFER failed");
}
- break;
- case DHCPREQUEST:
- DEBUG(LOG_INFO, "received REQUEST");
+ break;
+ case DHCPREQUEST:
+ DEBUG("received REQUEST");
requested = get_option(&packet, DHCP_REQUESTED_IP);
server_id = get_option(&packet, DHCP_SERVER_ID);
if (requested) memcpy(&requested_align, requested, 4);
if (server_id) memcpy(&server_id_align, server_id, 4);
-
- if (lease) { /*ADDME: or static lease */
+
+ if (lease) {
if (server_id) {
/* SELECTING State */
- DEBUG(LOG_INFO, "server_id = %08x", ntohl(server_id_align));
- if (server_id_align == server_config.server && requested &&
- requested_align == lease->yiaddr) {
+ DEBUG("server_id = %08x", ntohl(server_id_align));
+ if (server_id_align == server_config.server && requested
+ && requested_align == lease->yiaddr
+ ) {
sendACK(&packet, lease->yiaddr);
}
+ } else if (requested) {
+ /* INIT-REBOOT State */
+ if (lease->yiaddr == requested_align)
+ sendACK(&packet, lease->yiaddr);
+ else
+ sendNAK(&packet);
+ } else if (lease->yiaddr == packet.ciaddr) {
+ /* RENEWING or REBINDING State */
+ sendACK(&packet, lease->yiaddr);
} else {
- if (requested) {
- /* INIT-REBOOT State */
- if (lease->yiaddr == requested_align)
- sendACK(&packet, lease->yiaddr);
- else sendNAK(&packet);
- } else {
- /* RENEWING or REBINDING State */
- if (lease->yiaddr == packet.ciaddr)
- sendACK(&packet, lease->yiaddr);
- else {
- /* don't know what to do!!!! */
- sendNAK(&packet);
- }
- }
+ /* don't know what to do!!!! */
+ sendNAK(&packet);
}
-
+
/* what to do if we have no record of the client */
} else if (server_id) {
/* SELECTING State */
} else if (requested) {
/* INIT-REBOOT State */
- if ((lease = find_lease_by_yiaddr(requested_align))) {
+ lease = find_lease_by_yiaddr(requested_align);
+ if (lease) {
if (lease_expired(lease)) {
/* probably best if we drop this lease */
memset(lease->chaddr, 0, 16);
/* make some contention for this address */
- } else sendNAK(&packet);
- } else if (requested_align < server_config.start ||
- requested_align > server_config.end) {
- sendNAK(&packet);
- } /* else remain silent */
+ } else
+ sendNAK(&packet);
+ } else {
+ uint32_t r = ntohl(requested_align);
+ if (r < server_config.start_ip
+ || r > server_config.end_ip
+ ) {
+ sendNAK(&packet);
+ }
+ /* else remain silent */
+ }
} else {
- /* RENEWING or REBINDING State */
+ /* RENEWING or REBINDING State */
}
break;
case DHCPDECLINE:
- DEBUG(LOG_INFO,"received DECLINE");
+ DEBUG("Received DECLINE");
if (lease) {
memset(lease->chaddr, 0, 16);
lease->expires = time(0) + server_config.decline_time;
- }
+ }
break;
case DHCPRELEASE:
- DEBUG(LOG_INFO,"received RELEASE");
- if (lease) lease->expires = time(0);
+ DEBUG("Received RELEASE");
+ if (lease)
+ lease->expires = time(0);
break;
case DHCPINFORM:
- DEBUG(LOG_INFO,"received INFORM");
+ DEBUG("Received INFORM");
send_inform(&packet);
- break;
+ break;
default:
- LOG(LOG_WARNING, "unsupported DHCP message (%02x) -- ignoring", state[0]);
+ bb_info_msg("Unsupported DHCP message (%02x) - ignoring", state[0]);
}
}
-
- return 0;
+ ret0:
+ retval = 0;
+ ret:
+ /*if (server_config.pidfile) - server_config.pidfile is never NULL */
+ remove_pidfile(server_config.pidfile);
+ return retval;
}
-