4 This file is part of avahi.
6 avahi is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as
8 published by the Free Software Foundation; either version 2.1 of the
9 License, or (at your option) any later version.
11 avahi is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
14 Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with avahi; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
28 #include <sys/socket.h>
29 #include <netpacket/packet.h>
30 #include <net/ethernet.h>
37 #include <sys/types.h>
38 #include <arpa/inet.h>
39 #include <sys/ioctl.h>
47 #include <avahi-common/malloc.h>
48 #include <avahi-common/timeval.h>
50 #include <avahi-daemon/setproctitle.h>
52 #include <libdaemon/dfork.h>
53 #include <libdaemon/dsignal.h>
54 #include <libdaemon/dlog.h>
55 #include <libdaemon/dpid.h>
56 #include <libdaemon/dexec.h>
62 #error "avahi-autoipd is only available on Linux for now"
65 /* An implementation of RFC 3927 */
67 /* Constants from the RFC */
72 #define ANNOUNCE_WAIT 2
73 #define ANNOUNCE_NUM 2
74 #define ANNOUNCE_INTERVAL 2
75 #define MAX_CONFLICTS 10
76 #define RATE_LIMIT_INTERVAL 60
77 #define DEFEND_INTERVAL 10
79 #define IPV4LL_NETWORK 0xA9FE0000L
80 #define IPV4LL_NETMASK 0xFFFF0000L
81 #define IPV4LL_HOSTMASK 0x0000FFFFL
83 #define ETHER_ADDRLEN 6
84 #define ARP_PACKET_SIZE (8+4+4+2*ETHER_ADDRLEN)
86 typedef enum ArpOperation {
91 typedef struct ArpPacketInfo {
92 ArpOperation operation;
94 uint32_t sender_ip_address, target_ip_address;
95 uint8_t sender_hw_address[ETHER_ADDRLEN], target_hw_address[ETHER_ADDRLEN];
98 static State state = STATE_START;
99 static int n_iteration = 0;
100 static int n_conflict = 0;
102 static char *interface_name = NULL;
103 static char *pid_file_name = NULL;
104 static uint32_t start_address = 0;
105 static char *argv0 = NULL;
106 static int daemonize = 0;
107 static int wait_for_address = 0;
108 static int use_syslog = 0;
109 static int debug = 0;
110 static int modify_proc_title = 1;
119 } command = DAEMON_RUN;
121 typedef enum CalloutEvent {
129 #define RANDOM_DEVICE "/dev/urandom"
131 #define DEBUG(x) do {\
137 static void init_rand_seed(void) {
141 /* Try to initialize seed from /dev/urandom, to make it a little
142 * less predictable, and to make sure that multiple machines
143 * booted at the same time choose different random seeds. */
144 if ((fd = open(RANDOM_DEVICE, O_RDONLY)) >= 0) {
145 read(fd, &seed, sizeof(seed));
149 /* If the initialization failed by some reason, we add the time to the seed */
150 seed ^= (unsigned) time(NULL);
155 static uint32_t pick_addr(uint32_t old_addr) {
159 unsigned r = (unsigned) rand();
161 /* Reduce to 16 bits */
163 r = (r >> 16) ^ (r & 0xFFFF);
165 addr = htonl(IPV4LL_NETWORK | (uint32_t) r);
167 } while (addr == old_addr);
172 static void* packet_new(const ArpPacketInfo *info, size_t *packet_len) {
177 assert(info->operation == ARP_REQUEST || info->operation == ARP_RESPONSE);
179 *packet_len = ARP_PACKET_SIZE;
180 r = avahi_new0(uint8_t, *packet_len);
182 r[1] = 1; /* HTYPE */
183 r[2] = 8; /* PTYPE */
184 r[4] = ETHER_ADDRLEN; /* HLEN */
186 r[7] = (uint8_t) info->operation;
188 memcpy(r+8, info->sender_hw_address, ETHER_ADDRLEN);
189 memcpy(r+14, &info->sender_ip_address, 4);
190 memcpy(r+18, info->target_hw_address, ETHER_ADDRLEN);
191 memcpy(r+24, &info->target_ip_address, 4);
196 static void *packet_new_probe(uint32_t ip_address, const uint8_t*hw_address, size_t *packet_len) {
199 memset(&info, 0, sizeof(info));
200 info.operation = ARP_REQUEST;
201 memcpy(info.sender_hw_address, hw_address, ETHER_ADDRLEN);
202 info.target_ip_address = ip_address;
204 return packet_new(&info, packet_len);
207 static void *packet_new_announcement(uint32_t ip_address, const uint8_t* hw_address, size_t *packet_len) {
210 memset(&info, 0, sizeof(info));
211 info.operation = ARP_REQUEST;
212 memcpy(info.sender_hw_address, hw_address, ETHER_ADDRLEN);
213 info.target_ip_address = ip_address;
214 info.sender_ip_address = ip_address;
216 return packet_new(&info, packet_len);
219 static int packet_parse(const void *data, size_t packet_len, ArpPacketInfo *info) {
220 const uint8_t *p = data;
224 if (packet_len < ARP_PACKET_SIZE)
227 /* Check HTYPE and PTYPE */
228 if (p[0] != 0 || p[1] != 1 || p[2] != 8 || p[3] != 0)
231 /* Check HLEN, PLEN, OPERATION */
232 if (p[4] != ETHER_ADDRLEN || p[5] != 4 || p[6] != 0 || (p[7] != 1 && p[7] != 2))
235 info->operation = p[7];
236 memcpy(info->sender_hw_address, p+8, ETHER_ADDRLEN);
237 memcpy(&info->sender_ip_address, p+14, 4);
238 memcpy(info->target_hw_address, p+18, ETHER_ADDRLEN);
239 memcpy(&info->target_ip_address, p+24, 4);
244 static void set_state(State st, int reset_counter, uint32_t address) {
245 const char* const state_table[] = {
246 [STATE_START] = "START",
247 [STATE_WAITING_PROBE] = "WAITING_PROBE",
248 [STATE_PROBING] = "PROBING",
249 [STATE_WAITING_ANNOUNCE] = "WAITING_ANNOUNCE",
250 [STATE_ANNOUNCING] = "ANNOUNCING",
251 [STATE_RUNNING] = "RUNNING",
252 [STATE_SLEEPING] = "SLEEPING"
256 assert(st < STATE_MAX);
258 if (st == state && !reset_counter) {
260 DEBUG(daemon_log(LOG_DEBUG, "State iteration %s-%i", state_table[state], n_iteration));
262 DEBUG(daemon_log(LOG_DEBUG, "State transition %s-%i -> %s-0", state_table[state], n_iteration, state_table[st]));
267 if (modify_proc_title) {
268 if (state == STATE_SLEEPING)
269 avahi_set_proc_title("%s: sleeping", argv0);
270 else if (state == STATE_ANNOUNCING)
271 avahi_set_proc_title("%s: announcing %s", argv0, inet_ntop(AF_INET, &address, buf, sizeof(buf)));
272 else if (state == STATE_RUNNING)
273 avahi_set_proc_title("%s: bound %s", argv0, inet_ntop(AF_INET, &address, buf, sizeof(buf)));
275 avahi_set_proc_title("%s: probing %s", argv0, inet_ntop(AF_INET, &address, buf, sizeof(buf)));
279 static int interface_up(int iface) {
283 if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
284 daemon_log(LOG_ERR, "socket() failed: %s", strerror(errno));
288 memset(&ifreq, 0, sizeof(ifreq));
289 if (!if_indextoname(iface, ifreq.ifr_name)) {
290 daemon_log(LOG_ERR, "if_indextoname() failed: %s", strerror(errno));
294 if (ioctl(fd, SIOCGIFFLAGS, &ifreq) < 0) {
295 daemon_log(LOG_ERR, "SIOCGIFFLAGS failed: %s", strerror(errno));
299 ifreq.ifr_flags |= IFF_UP;
301 if (ioctl(fd, SIOCSIFFLAGS, &ifreq) < 0) {
302 daemon_log(LOG_ERR, "SIOCSIFFLAGS failed: %s", strerror(errno));
317 static int do_callout(CalloutEvent event, int iface, uint32_t addr) {
318 char buf[64], ifname[IFNAMSIZ];
319 const char * const event_table[CALLOUT_MAX] = {
320 [CALLOUT_BIND] = "BIND",
321 [CALLOUT_CONFLICT] = "CONFLICT",
322 [CALLOUT_UNBIND] = "UNBIND",
323 [CALLOUT_STOP] = "STOP"
326 daemon_log(LOG_INFO, "Callout %s, address %s on interface %s",
328 inet_ntop(AF_INET, &addr, buf, sizeof(buf)),
329 if_indextoname(iface, ifname));
334 static int open_socket(int iface, uint8_t *hw_address) {
336 struct sockaddr_ll sa;
339 if (interface_up(iface) < 0)
342 if ((fd = socket(PF_PACKET, SOCK_DGRAM, 0)) < 0) {
343 daemon_log(LOG_ERR, "socket() failed: %s", strerror(errno));
347 memset(&sa, 0, sizeof(sa));
348 sa.sll_family = AF_PACKET;
349 sa.sll_protocol = htons(ETH_P_ARP);
350 sa.sll_ifindex = iface;
352 if (bind(fd, (struct sockaddr*) &sa, sizeof(sa)) < 0) {
353 daemon_log(LOG_ERR, "bind() failed: %s", strerror(errno));
358 if (getsockname(fd, (struct sockaddr*) &sa, &sa_len) < 0) {
359 daemon_log(LOG_ERR, "getsockname() failed: %s", strerror(errno));
363 if (sa.sll_halen != ETHER_ADDRLEN) {
364 daemon_log(LOG_ERR, "getsockname() returned invalid hardware address.");
368 memcpy(hw_address, sa.sll_addr, ETHER_ADDRLEN);
379 static int send_packet(int fd, int iface, void *packet, size_t packet_len) {
380 struct sockaddr_ll sa;
384 assert(packet_len > 0);
386 memset(&sa, 0, sizeof(sa));
387 sa.sll_family = AF_PACKET;
388 sa.sll_protocol = htons(ETH_P_ARP);
389 sa.sll_ifindex = iface;
390 sa.sll_halen = ETHER_ADDRLEN;
391 memset(sa.sll_addr, 0xFF, ETHER_ADDRLEN);
393 if (sendto(fd, packet, packet_len, 0, (struct sockaddr*) &sa, sizeof(sa)) < 0) {
394 daemon_log(LOG_ERR, "sendto() failed: %s", strerror(errno));
401 static int recv_packet(int fd, void **packet, size_t *packet_len) {
403 struct sockaddr_ll sa;
413 if (ioctl(fd, FIONREAD, &s) < 0) {
414 daemon_log(LOG_ERR, "FIONREAD failed: %s", strerror(errno));
421 *packet = avahi_new(uint8_t, s);
424 if ((r = recvfrom(fd, *packet, s, 0, (struct sockaddr*) &sa, &sa_len)) < 0) {
425 daemon_log(LOG_ERR, "recvfrom() failed: %s", strerror(errno));
429 *packet_len = (size_t) r;
442 int is_ll_address(uint32_t addr) {
443 return (ntohl(addr) & IPV4LL_NETMASK) == IPV4LL_NETWORK;
446 static struct timeval *elapse_time(struct timeval *tv, unsigned msec, unsigned jitter) {
449 gettimeofday(tv, NULL);
452 avahi_timeval_add(tv, (AvahiUsec) msec*1000);
455 avahi_timeval_add(tv, (AvahiUsec) (jitter*1000.0*rand()/(RAND_MAX+1.0)));
460 static int loop(int iface, uint32_t addr) {
468 int fd = -1, ret = -1;
469 struct timeval next_wakeup;
470 int next_wakeup_valid = 0;
472 void *in_packet = NULL;
473 size_t in_packet_len;
474 void *out_packet = NULL;
475 size_t out_packet_len;
476 uint8_t hw_address[ETHER_ADDRLEN];
477 struct pollfd pollfds[FD_MAX];
479 Event event = EVENT_NULL;
480 int retval_sent = !daemonize;
483 daemon_signal_init(SIGINT, SIGTERM, SIGCHLD, SIGHUP,0);
485 if ((fd = open_socket(iface, hw_address)) < 0)
488 if ((iface_fd = iface_init(iface)) < 0)
491 if (iface_get_initial_state(&st) < 0)
494 if (addr && !is_ll_address(addr)) {
495 daemon_log(LOG_WARNING, "Requested address %s is not from IPv4LL range 169.254/16, ignoring.", inet_ntop(AF_INET, &addr, buf, sizeof(buf)));
503 for (i = 0; i < ETHER_ADDRLEN; i++)
504 a += hw_address[i]*i;
506 addr = htonl(IPV4LL_NETWORK | (uint32_t) a);
509 set_state(st, 1, addr);
511 daemon_log(LOG_INFO, "Starting with address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf)));
513 if (state == STATE_SLEEPING)
514 daemon_log(LOG_INFO, "Routable address already assigned, sleeping.");
516 if (!retval_sent && (!wait_for_address || state == STATE_SLEEPING)) {
517 daemon_retval_send(0);
521 memset(pollfds, 0, sizeof(pollfds));
522 pollfds[FD_ARP].fd = fd;
523 pollfds[FD_ARP].events = POLLIN;
524 pollfds[FD_IFACE].fd = iface_fd;
525 pollfds[FD_IFACE].events = POLLIN;
526 pollfds[FD_SIGNAL].fd = daemon_signal_fd();
527 pollfds[FD_SIGNAL].events = POLLIN;
533 if (state == STATE_START) {
535 /* First, wait a random time */
536 set_state(STATE_WAITING_PROBE, 1, addr);
538 elapse_time(&next_wakeup, 0, PROBE_WAIT*1000);
539 next_wakeup_valid = 1;
541 } else if ((state == STATE_WAITING_PROBE && event == EVENT_TIMEOUT) ||
542 (state == STATE_PROBING && event == EVENT_TIMEOUT && n_iteration < PROBE_NUM-2)) {
545 out_packet = packet_new_probe(addr, hw_address, &out_packet_len);
546 set_state(STATE_PROBING, 0, addr);
548 elapse_time(&next_wakeup, PROBE_MIN*1000, (PROBE_MAX-PROBE_MIN)*1000);
549 next_wakeup_valid = 1;
551 } else if (state == STATE_PROBING && event == EVENT_TIMEOUT && n_iteration >= PROBE_NUM-2) {
553 /* Send the last probe */
554 out_packet = packet_new_probe(addr, hw_address, &out_packet_len);
555 set_state(STATE_WAITING_ANNOUNCE, 1, addr);
557 elapse_time(&next_wakeup, ANNOUNCE_WAIT*1000, 0);
558 next_wakeup_valid = 1;
560 } else if ((state == STATE_WAITING_ANNOUNCE && event == EVENT_TIMEOUT) ||
561 (state == STATE_ANNOUNCING && event == EVENT_TIMEOUT && n_iteration < ANNOUNCE_NUM-1)) {
563 /* Send announcement packet */
564 out_packet = packet_new_announcement(addr, hw_address, &out_packet_len);
565 set_state(STATE_ANNOUNCING, 0, addr);
567 elapse_time(&next_wakeup, ANNOUNCE_INTERVAL*1000, 0);
568 next_wakeup_valid = 1;
570 if (n_iteration == 0) {
571 do_callout(CALLOUT_BIND, iface, addr);
575 daemon_retval_send(0);
580 } else if ((state == STATE_ANNOUNCING && event == EVENT_TIMEOUT && n_iteration >= ANNOUNCE_NUM-1)) {
582 daemon_log(LOG_INFO, "Successfully claimed IP address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf)));
583 set_state(STATE_RUNNING, 0, addr);
585 next_wakeup_valid = 0;
587 } else if (event == EVENT_PACKET) {
592 if (packet_parse(in_packet, in_packet_len, &info) < 0)
593 daemon_log(LOG_WARNING, "Failed to parse incoming ARP packet.");
597 if (info.sender_ip_address == addr) {
598 /* Normal conflict */
600 daemon_log(LOG_INFO, "Recieved conflicting normal ARP packet.");
601 } else if (state == STATE_WAITING_PROBE || state == STATE_PROBING || state == STATE_WAITING_ANNOUNCE) {
603 conflict = info.target_ip_address == addr && memcmp(hw_address, info.sender_hw_address, ETHER_ADDRLEN);
604 daemon_log(LOG_INFO, "Recieved conflicting probe ARP packet.");
609 if (state == STATE_RUNNING || state == STATE_ANNOUNCING)
610 do_callout(CALLOUT_CONFLICT, iface, addr);
612 /* Pick a new address */
613 addr = pick_addr(addr);
615 daemon_log(LOG_INFO, "Trying address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf)));
619 set_state(STATE_WAITING_PROBE, 1, addr);
621 if (n_conflict >= MAX_CONFLICTS) {
622 daemon_log(LOG_WARNING, "Got too many conflicts, rate limiting new probes.");
623 elapse_time(&next_wakeup, RATE_LIMIT_INTERVAL*1000, PROBE_WAIT*1000);
625 elapse_time(&next_wakeup, 0, PROBE_WAIT*1000);
627 next_wakeup_valid = 1;
629 DEBUG(daemon_log(LOG_DEBUG, "Ignoring irrelevant ARP packet."));
632 } else if (event == EVENT_ROUTABLE_ADDR_CONFIGURED) {
634 daemon_log(LOG_INFO, "A routable address has been configured.");
636 if (state == STATE_RUNNING || state == STATE_ANNOUNCING)
637 do_callout(CALLOUT_UNBIND, iface, addr);
640 daemon_retval_send(0);
644 set_state(STATE_SLEEPING, 1, addr);
645 next_wakeup_valid = 0;
647 } else if (event == EVENT_ROUTABLE_ADDR_UNCONFIGURED && state == STATE_SLEEPING) {
649 daemon_log(LOG_INFO, "No longer a routable address configured, restarting probe process.");
651 set_state(STATE_WAITING_PROBE, 1, addr);
653 elapse_time(&next_wakeup, 0, PROBE_WAIT*1000);
654 next_wakeup_valid = 1;
656 } else if (event == EVENT_REFRESH_REQUEST && state == STATE_RUNNING) {
658 /* The user requested a reannouncing of the address by a SIGHUP */
659 daemon_log(LOG_INFO, "Reannouncing address.");
661 /* Send announcement packet */
662 out_packet = packet_new_announcement(addr, hw_address, &out_packet_len);
663 set_state(STATE_ANNOUNCING, 1, addr);
665 elapse_time(&next_wakeup, ANNOUNCE_INTERVAL*1000, 0);
666 next_wakeup_valid = 1;
670 DEBUG(daemon_log(LOG_DEBUG, "sending..."));
672 if (send_packet(fd, iface, out_packet, out_packet_len) < 0)
675 avahi_free(out_packet);
680 avahi_free(in_packet);
687 if (next_wakeup_valid) {
688 usec = avahi_age(&next_wakeup);
689 timeout = usec < 0 ? (int) (-usec/1000) : 0;
692 DEBUG(daemon_log(LOG_DEBUG, "sleeping %ims", timeout));
694 while ((r = poll(pollfds, FD_MAX, timeout)) < 0 && errno == EINTR)
698 daemon_log(LOG_ERR, "poll() failed: %s", strerror(r));
701 event = EVENT_TIMEOUT;
702 next_wakeup_valid = 0;
706 if (pollfds[FD_ARP].revents) {
708 if (pollfds[FD_ARP].revents == POLLERR) {
709 /* The interface is probably down, let's recreate our socket */
713 if ((fd = open_socket(iface, hw_address)) < 0)
716 pollfds[FD_ARP].fd = fd;
720 assert(pollfds[FD_ARP].revents == POLLIN);
722 if (recv_packet(fd, &in_packet, &in_packet_len) < 0)
726 event = EVENT_PACKET;
730 if (event == EVENT_NULL &&
731 pollfds[FD_IFACE].revents) {
733 assert(pollfds[FD_IFACE].revents == POLLIN);
735 if (iface_process(&event) < 0)
739 if (event == EVENT_NULL &&
740 pollfds[FD_SIGNAL].revents) {
743 assert(pollfds[FD_SIGNAL].revents == POLLIN);
745 if ((sig = daemon_signal_next()) <= 0) {
746 daemon_log(LOG_ERR, "daemon_signal_next() failed");
753 daemon_log(LOG_INFO, "Got %s, quitting.", sig == SIGINT ? "SIGINT" : "SIGTERM");
758 waitpid(-1, NULL, WNOHANG);
762 event = EVENT_REFRESH_REQUEST;
774 if (state == STATE_RUNNING || state == STATE_ANNOUNCING)
775 do_callout(CALLOUT_STOP, iface, addr);
777 avahi_free(out_packet);
778 avahi_free(in_packet);
786 if (daemonize && !retval_sent)
787 daemon_retval_send(ret);
793 static void help(FILE *f, const char *a0) {
795 "%s [options] INTERFACE\n"
796 " -h --help Show this help\n"
797 " -D --daemonize Daemonize after startup\n"
798 " -s --syslog Write log messages to syslog(3) instead of STDERR\n"
799 " -k --kill Kill a running daemon\n"
800 " -r --refresh Request a running daemon to refresh it's IP address\n"
801 " -c --check Return 0 if a daemon is already running\n"
802 " -V --version Show version\n"
803 " -S --start=ADDRESS Start with this address from the IPv4LL range 169.254.0.0/16\n"
804 " -w --wait Wait until an address has been acquired before daemonizing\n"
805 " --no-proc-title Don't modify process title\n"
806 " --debug Increase verbosity\n",
810 static int parse_command_line(int argc, char *argv[]) {
814 OPTION_NO_PROC_TITLE = 256,
818 static const struct option long_options[] = {
819 { "help", no_argument, NULL, 'h' },
820 { "daemonize", no_argument, NULL, 'D' },
821 { "syslog", no_argument, NULL, 's' },
822 { "kill", no_argument, NULL, 'k' },
823 { "refresh", no_argument, NULL, 'r' },
824 { "check", no_argument, NULL, 'c' },
825 { "version", no_argument, NULL, 'V' },
826 { "start", required_argument, NULL, 'S' },
827 { "wait", no_argument, NULL, 'w' },
828 { "no-proc-title", no_argument, NULL, OPTION_NO_PROC_TITLE },
829 { "debug", no_argument, NULL, OPTION_DEBUG },
834 while ((c = getopt_long(argc, argv, "hDkVrcS:", long_options, NULL)) >= 0) {
841 command = DAEMON_HELP;
847 command = DAEMON_KILL;
850 command = DAEMON_VERSION;
853 command = DAEMON_REFRESH;
856 command = DAEMON_CHECK;
860 if ((start_address = inet_addr(optarg)) == (uint32_t) -1) {
861 fprintf(stderr, "Failed to parse IP address '%s'.", optarg);
866 wait_for_address = 1;
869 case OPTION_NO_PROC_TITLE:
870 modify_proc_title = 0;
878 fprintf(stderr, "Invalid command line argument: %c\n", c);
883 if (command == DAEMON_RUN ||
884 command == DAEMON_KILL ||
885 command == DAEMON_REFRESH ||
886 command == DAEMON_CHECK) {
888 if (optind >= argc) {
889 fprintf(stderr, "Missing interface name.\n");
893 interface_name = argv[optind++];
896 if (optind != argc) {
897 fprintf(stderr, "Too many arguments\n");
904 static const char* pid_file_proc(void) {
905 return pid_file_name;
908 int main(int argc, char*argv[]) {
910 int wrote_pid_file = 0;
912 avahi_init_proc_title(argc, argv);
914 if ((argv0 = strrchr(argv[0], '/')))
919 daemon_pid_file_ident = daemon_log_ident = argv0;
920 daemon_pid_file_proc = pid_file_proc;
922 if (parse_command_line(argc, argv) < 0)
925 pid_file_name = avahi_strdup_printf(AVAHI_RUNTIME_DIR"/avahi-autoipd.%s.pid", interface_name);
927 if (command == DAEMON_RUN) {
933 if ((ifindex = if_nametoindex(interface_name)) <= 0) {
934 daemon_log(LOG_ERR, "Failed to get index for interface name '%s': %s", interface_name, strerror(errno));
939 daemon_log(LOG_ERR, "This program is intended to be run as root.");
943 if ((pid = daemon_pid_file_is_running()) >= 0) {
944 daemon_log(LOG_ERR, "Daemon already running on PID %u", pid);
949 daemon_retval_init();
951 if ((pid = daemon_fork()) < 0)
957 if ((ret = daemon_retval_wait(20)) < 0) {
958 daemon_log(LOG_ERR, "Could not receive return value from daemon process.");
969 if (use_syslog || daemonize)
970 daemon_log_use = DAEMON_LOG_SYSLOG;
974 if (daemon_pid_file_create() < 0) {
975 daemon_log(LOG_ERR, "Failed to create PID file: %s", strerror(errno));
978 daemon_retval_send(1);
983 if (loop(ifindex, start_address) < 0)
987 } else if (command == DAEMON_HELP) {
991 } else if (command == DAEMON_VERSION) {
992 printf("%s "PACKAGE_VERSION"\n", argv0);
995 } else if (command == DAEMON_KILL) {
996 if (daemon_pid_file_kill_wait(SIGTERM, 5) < 0) {
997 daemon_log(LOG_WARNING, "Failed to kill daemon: %s", strerror(errno));
1002 } else if (command == DAEMON_REFRESH) {
1003 if (daemon_pid_file_kill(SIGHUP) < 0) {
1004 daemon_log(LOG_WARNING, "Failed to kill daemon: %s", strerror(errno));
1009 } else if (command == DAEMON_CHECK)
1010 r = (daemon_pid_file_is_running() >= 0) ? 0 : 1;
1016 daemon_retval_done();
1019 daemon_pid_file_remove();
1026 - chroot/drop privs/caps
1028 - store last used address