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>
49 #include <avahi-common/malloc.h>
50 #include <avahi-common/timeval.h>
52 #include <avahi-daemon/setproctitle.h>
54 #include <libdaemon/dfork.h>
55 #include <libdaemon/dsignal.h>
56 #include <libdaemon/dlog.h>
57 #include <libdaemon/dpid.h>
58 #include <libdaemon/dexec.h>
64 #error "avahi-autoipd is only available on Linux for now"
67 /* An implementation of RFC 3927 */
69 /* Constants from the RFC */
74 #define ANNOUNCE_WAIT 2
75 #define ANNOUNCE_NUM 2
76 #define ANNOUNCE_INTERVAL 2
77 #define MAX_CONFLICTS 10
78 #define RATE_LIMIT_INTERVAL 60
79 #define DEFEND_INTERVAL 10
81 #define IPV4LL_NETWORK 0xA9FE0000L
82 #define IPV4LL_NETMASK 0xFFFF0000L
83 #define IPV4LL_HOSTMASK 0x0000FFFFL
84 #define IPV4LL_BROADCAST 0xA9FEFFFFL
86 #define ETHER_ADDRLEN 6
87 #define ARP_PACKET_SIZE (8+4+4+2*ETHER_ADDRLEN)
89 typedef enum ArpOperation {
94 typedef struct ArpPacketInfo {
95 ArpOperation operation;
97 uint32_t sender_ip_address, target_ip_address;
98 uint8_t sender_hw_address[ETHER_ADDRLEN], target_hw_address[ETHER_ADDRLEN];
101 static State state = STATE_START;
102 static int n_iteration = 0;
103 static int n_conflict = 0;
105 static char *interface_name = NULL;
106 static char *pid_file_name = NULL;
107 static uint32_t start_address = 0;
108 static char *argv0 = NULL;
109 static int daemonize = 0;
110 static int wait_for_address = 0;
111 static int use_syslog = 0;
112 static int debug = 0;
113 static int modify_proc_title = 1;
114 static int force_bind = 0;
116 static int no_chroot = 0;
118 static int no_drop_root = 0;
119 static int wrote_pid_file = 0;
128 } command = DAEMON_RUN;
130 typedef enum CalloutEvent {
138 static const char * const callout_event_table[CALLOUT_MAX] = {
139 [CALLOUT_BIND] = "BIND",
140 [CALLOUT_CONFLICT] = "CONFLICT",
141 [CALLOUT_UNBIND] = "UNBIND",
142 [CALLOUT_STOP] = "STOP"
145 typedef struct CalloutEventInfo {
151 #define RANDOM_DEVICE "/dev/urandom"
153 #define DEBUG(x) do {\
159 static void init_rand_seed(void) {
163 /* Try to initialize seed from /dev/urandom, to make it a little
164 * less predictable, and to make sure that multiple machines
165 * booted at the same time choose different random seeds. */
166 if ((fd = open(RANDOM_DEVICE, O_RDONLY)) >= 0) {
167 read(fd, &seed, sizeof(seed));
171 /* If the initialization failed by some reason, we add the time to the seed */
172 seed ^= (unsigned) time(NULL);
177 static uint32_t pick_addr(uint32_t old_addr) {
181 unsigned r = (unsigned) rand();
183 /* Reduce to 16 bits */
185 r = (r >> 16) ^ (r & 0xFFFF);
187 addr = htonl(IPV4LL_NETWORK | (uint32_t) r);
189 } while (addr == old_addr || !is_ll_address(addr));
194 static int load_address(const char *fn, uint32_t *addr) {
201 if (!(f = fopen(fn, "r"))) {
203 if (errno == ENOENT) {
208 daemon_log(LOG_ERR, "fopen() failed: %s", strerror(errno));
212 if (fscanf(f, "%u.%u.%u.%u\n", &a, &b, &c, &d) != 4) {
213 daemon_log(LOG_ERR, "Parse failure");
219 *addr = htonl((a << 24) | (b << 16) | (c << 8) | d);
229 static int save_address(const char *fn, uint32_t addr) {
235 if (!(f = fopen(fn, "w"))) {
236 daemon_log(LOG_ERR, "fopen() failed: %s", strerror(errno));
240 fprintf(f, "%s\n", inet_ntop(AF_INET, &addr, buf, sizeof (buf)));
252 static void* packet_new(const ArpPacketInfo *info, size_t *packet_len) {
257 assert(info->operation == ARP_REQUEST || info->operation == ARP_RESPONSE);
259 *packet_len = ARP_PACKET_SIZE;
260 r = avahi_new0(uint8_t, *packet_len);
262 r[1] = 1; /* HTYPE */
263 r[2] = 8; /* PTYPE */
264 r[4] = ETHER_ADDRLEN; /* HLEN */
266 r[7] = (uint8_t) info->operation;
268 memcpy(r+8, info->sender_hw_address, ETHER_ADDRLEN);
269 memcpy(r+14, &info->sender_ip_address, 4);
270 memcpy(r+18, info->target_hw_address, ETHER_ADDRLEN);
271 memcpy(r+24, &info->target_ip_address, 4);
276 static void *packet_new_probe(uint32_t ip_address, const uint8_t*hw_address, size_t *packet_len) {
279 memset(&info, 0, sizeof(info));
280 info.operation = ARP_REQUEST;
281 memcpy(info.sender_hw_address, hw_address, ETHER_ADDRLEN);
282 info.target_ip_address = ip_address;
284 return packet_new(&info, packet_len);
287 static void *packet_new_announcement(uint32_t ip_address, const uint8_t* hw_address, size_t *packet_len) {
290 memset(&info, 0, sizeof(info));
291 info.operation = ARP_REQUEST;
292 memcpy(info.sender_hw_address, hw_address, ETHER_ADDRLEN);
293 info.target_ip_address = ip_address;
294 info.sender_ip_address = ip_address;
296 return packet_new(&info, packet_len);
299 static int packet_parse(const void *data, size_t packet_len, ArpPacketInfo *info) {
300 const uint8_t *p = data;
304 if (packet_len < ARP_PACKET_SIZE)
307 /* Check HTYPE and PTYPE */
308 if (p[0] != 0 || p[1] != 1 || p[2] != 8 || p[3] != 0)
311 /* Check HLEN, PLEN, OPERATION */
312 if (p[4] != ETHER_ADDRLEN || p[5] != 4 || p[6] != 0 || (p[7] != 1 && p[7] != 2))
315 info->operation = p[7];
316 memcpy(info->sender_hw_address, p+8, ETHER_ADDRLEN);
317 memcpy(&info->sender_ip_address, p+14, 4);
318 memcpy(info->target_hw_address, p+18, ETHER_ADDRLEN);
319 memcpy(&info->target_ip_address, p+24, 4);
324 static void set_state(State st, int reset_counter, uint32_t address) {
325 static const char* const state_table[] = {
326 [STATE_START] = "START",
327 [STATE_WAITING_PROBE] = "WAITING_PROBE",
328 [STATE_PROBING] = "PROBING",
329 [STATE_WAITING_ANNOUNCE] = "WAITING_ANNOUNCE",
330 [STATE_ANNOUNCING] = "ANNOUNCING",
331 [STATE_RUNNING] = "RUNNING",
332 [STATE_SLEEPING] = "SLEEPING"
336 assert(st < STATE_MAX);
338 if (st == state && !reset_counter) {
340 DEBUG(daemon_log(LOG_DEBUG, "State iteration %s-%i", state_table[state], n_iteration));
342 DEBUG(daemon_log(LOG_DEBUG, "State transition %s-%i -> %s-0", state_table[state], n_iteration, state_table[st]));
347 if (state == STATE_SLEEPING)
348 avahi_set_proc_title(argv0, "%s: [%s] sleeping", argv0, interface_name);
349 else if (state == STATE_ANNOUNCING)
350 avahi_set_proc_title(argv0, "%s: [%s] announcing %s", argv0, interface_name, inet_ntop(AF_INET, &address, buf, sizeof(buf)));
351 else if (state == STATE_RUNNING)
352 avahi_set_proc_title(argv0, "%s: [%s] bound %s", argv0, interface_name, inet_ntop(AF_INET, &address, buf, sizeof(buf)));
354 avahi_set_proc_title(argv0, "%s: [%s] probing %s", argv0, interface_name, inet_ntop(AF_INET, &address, buf, sizeof(buf)));
357 static int interface_up(int iface) {
361 if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
362 daemon_log(LOG_ERR, "socket() failed: %s", strerror(errno));
366 memset(&ifreq, 0, sizeof(ifreq));
367 if (!if_indextoname(iface, ifreq.ifr_name)) {
368 daemon_log(LOG_ERR, "if_indextoname() failed: %s", strerror(errno));
372 if (ioctl(fd, SIOCGIFFLAGS, &ifreq) < 0) {
373 daemon_log(LOG_ERR, "SIOCGIFFLAGS failed: %s", strerror(errno));
377 ifreq.ifr_flags |= IFF_UP;
379 if (ioctl(fd, SIOCSIFFLAGS, &ifreq) < 0) {
380 daemon_log(LOG_ERR, "SIOCSIFFLAGS failed: %s", strerror(errno));
395 static int open_socket(int iface, uint8_t *hw_address) {
397 struct sockaddr_ll sa;
400 if (interface_up(iface) < 0)
403 if ((fd = socket(PF_PACKET, SOCK_DGRAM, 0)) < 0) {
404 daemon_log(LOG_ERR, "socket() failed: %s", strerror(errno));
408 memset(&sa, 0, sizeof(sa));
409 sa.sll_family = AF_PACKET;
410 sa.sll_protocol = htons(ETH_P_ARP);
411 sa.sll_ifindex = iface;
413 if (bind(fd, (struct sockaddr*) &sa, sizeof(sa)) < 0) {
414 daemon_log(LOG_ERR, "bind() failed: %s", strerror(errno));
419 if (getsockname(fd, (struct sockaddr*) &sa, &sa_len) < 0) {
420 daemon_log(LOG_ERR, "getsockname() failed: %s", strerror(errno));
424 if (sa.sll_halen != ETHER_ADDRLEN) {
425 daemon_log(LOG_ERR, "getsockname() returned invalid hardware address.");
429 memcpy(hw_address, sa.sll_addr, ETHER_ADDRLEN);
440 static int send_packet(int fd, int iface, void *packet, size_t packet_len) {
441 struct sockaddr_ll sa;
445 assert(packet_len > 0);
447 memset(&sa, 0, sizeof(sa));
448 sa.sll_family = AF_PACKET;
449 sa.sll_protocol = htons(ETH_P_ARP);
450 sa.sll_ifindex = iface;
451 sa.sll_halen = ETHER_ADDRLEN;
452 memset(sa.sll_addr, 0xFF, ETHER_ADDRLEN);
454 if (sendto(fd, packet, packet_len, 0, (struct sockaddr*) &sa, sizeof(sa)) < 0) {
455 daemon_log(LOG_ERR, "sendto() failed: %s", strerror(errno));
462 static int recv_packet(int fd, void **packet, size_t *packet_len) {
464 struct sockaddr_ll sa;
474 if (ioctl(fd, FIONREAD, &s) < 0) {
475 daemon_log(LOG_ERR, "FIONREAD failed: %s", strerror(errno));
482 *packet = avahi_new(uint8_t, s);
485 if ((r = recvfrom(fd, *packet, s, 0, (struct sockaddr*) &sa, &sa_len)) < 0) {
486 daemon_log(LOG_ERR, "recvfrom() failed: %s", strerror(errno));
490 *packet_len = (size_t) r;
503 int is_ll_address(uint32_t addr) {
505 (ntohl(addr) & IPV4LL_NETMASK) == IPV4LL_NETWORK &&
506 ntohl(addr) != IPV4LL_NETWORK &&
507 ntohl(addr) != IPV4LL_BROADCAST;
510 static struct timeval *elapse_time(struct timeval *tv, unsigned msec, unsigned jitter) {
513 gettimeofday(tv, NULL);
516 avahi_timeval_add(tv, (AvahiUsec) msec*1000);
519 avahi_timeval_add(tv, (AvahiUsec) (jitter*1000.0*rand()/(RAND_MAX+1.0)));
524 static FILE* fork_dispatcher(void) {
530 daemon_log(LOG_ERR, "pipe() failed: %s", strerror(errno));
534 if ((pid = fork()) < 0)
540 /* Please note that the signal pipe is not closed at this
541 * point, signals will thus be dispatched in the main
544 daemon_retval_done();
548 avahi_set_proc_title(argv0, "%s: [%s] callout dispatcher", argv0, interface_name);
552 if (!(f = fdopen(fds[0], "r"))) {
553 daemon_log(LOG_ERR, "fdopen() failed: %s", strerror(errno));
554 goto dispatcher_fail;
558 CalloutEventInfo info;
559 char name[IFNAMSIZ], buf[64];
562 if (fread(&info, sizeof(info), 1, f) != 1) {
566 daemon_log(LOG_ERR, "fread() failed: %s", strerror(errno));
567 goto dispatcher_fail;
570 assert(info.event <= CALLOUT_MAX);
572 if (!if_indextoname(info.ifindex, name)) {
573 daemon_log(LOG_ERR, "if_indextoname() failed: %s", strerror(errno));
577 if (daemon_exec("/", &k,
578 AVAHI_IPCONF_SCRIPT, AVAHI_IPCONF_SCRIPT,
579 callout_event_table[info.event],
581 inet_ntop(AF_INET, &info.address, buf, sizeof(buf)), NULL) < 0) {
583 daemon_log(LOG_ERR, "Failed to run script: %s", strerror(errno));
588 daemon_log(LOG_WARNING, "Script execution failed with return value %i", k);
599 /* If the main process is trapped inside a chroot() we have to
600 * remove the PID file for it */
602 if (!no_chroot && wrote_pid_file)
603 daemon_pid_file_remove();
614 if (!(ret = fdopen(fds[1], "w"))) {
615 daemon_log(LOG_ERR, "fdopen() failed: %s", strerror(errno));
630 static int do_callout(FILE *f, CalloutEvent event, int iface, uint32_t addr) {
631 CalloutEventInfo info;
632 char buf[64], ifname[IFNAMSIZ];
634 daemon_log(LOG_INFO, "Callout %s, address %s on interface %s",
635 callout_event_table[event],
636 inet_ntop(AF_INET, &addr, buf, sizeof(buf)),
637 if_indextoname(iface, ifname));
640 info.ifindex = iface;
643 if (fwrite(&info, sizeof(info), 1, f) != 1 || fflush(f) != 0) {
644 daemon_log(LOG_ERR, "Failed to write callout event: %s", strerror(errno));
651 #define set_env(key, value) putenv(avahi_strdup_printf("%s=%s", (key), (value)))
653 static int drop_privs(void) {
659 /* Get user/group ID */
663 if (!(pw = getpwnam(AVAHI_AUTOIPD_USER))) {
664 daemon_log(LOG_ERR, "Failed to find user '"AVAHI_AUTOIPD_USER"'.");
668 if (!(gr = getgrnam(AVAHI_AUTOIPD_GROUP))) {
669 daemon_log(LOG_ERR, "Failed to find group '"AVAHI_AUTOIPD_GROUP"'.");
673 daemon_log(LOG_INFO, "Found user '"AVAHI_AUTOIPD_USER"' (UID %lu) and group '"AVAHI_AUTOIPD_GROUP"' (GID %lu).", (unsigned long) pw->pw_uid, (unsigned long) gr->gr_gid);
676 /* Create directory */
678 r = mkdir(AVAHI_IPDATA_DIR, 0755);
681 if (r < 0 && errno != EEXIST) {
682 daemon_log(LOG_ERR, "mkdir(\""AVAHI_IPDATA_DIR"\"): %s", strerror(errno));
686 /* Convey working directory */
691 chown(AVAHI_IPDATA_DIR, pw->pw_uid, gr->gr_gid);
693 if (stat(AVAHI_IPDATA_DIR, &st) < 0) {
694 daemon_log(LOG_ERR, "stat(): %s\n", strerror(errno));
698 if (!S_ISDIR(st.st_mode) || st.st_uid != pw->pw_uid || st.st_gid != gr->gr_gid) {
699 daemon_log(LOG_ERR, "Failed to create runtime directory "AVAHI_IPDATA_DIR".");
707 if (chroot(AVAHI_IPDATA_DIR) < 0) {
708 daemon_log(LOG_ERR, "Failed to chroot(): %s", strerror(errno));
712 daemon_log(LOG_INFO, "Successfully called chroot().");
715 /* Since we are now trapped inside a chroot we cannot remove
716 * the pid file anymore, the helper process will do that for us. */
724 if (initgroups(AVAHI_AUTOIPD_USER, gr->gr_gid) != 0) {
725 daemon_log(LOG_ERR, "Failed to change group list: %s", strerror(errno));
729 #if defined(HAVE_SETRESGID)
730 r = setresgid(gr->gr_gid, gr->gr_gid, gr->gr_gid);
731 #elif defined(HAVE_SETEGID)
732 if ((r = setgid(gr->gr_gid)) >= 0)
733 r = setegid(gr->gr_gid);
734 #elif defined(HAVE_SETREGID)
735 r = setregid(gr->gr_gid, gr->gr_gid);
737 #error "No API to drop priviliges"
741 daemon_log(LOG_ERR, "Failed to change GID: %s", strerror(errno));
745 #if defined(HAVE_SETRESUID)
746 r = setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid);
747 #elif defined(HAVE_SETEUID)
748 if ((r = setuid(pw->pw_uid)) >= 0)
749 r = seteuid(pw->pw_uid);
750 #elif defined(HAVE_SETREUID)
751 r = setreuid(pw->pw_uid, pw->pw_uid);
753 #error "No API to drop priviliges"
757 daemon_log(LOG_ERR, "Failed to change UID: %s", strerror(errno));
761 set_env("USER", pw->pw_name);
762 set_env("LOGNAME", pw->pw_name);
763 set_env("HOME", pw->pw_dir);
765 daemon_log(LOG_ERR, "Successfully dropped root privileges.");
771 static int loop(int iface, uint32_t addr) {
779 int fd = -1, ret = -1;
780 struct timeval next_wakeup;
781 int next_wakeup_valid = 0;
783 void *in_packet = NULL;
784 size_t in_packet_len;
785 void *out_packet = NULL;
786 size_t out_packet_len;
787 uint8_t hw_address[ETHER_ADDRLEN];
788 struct pollfd pollfds[FD_MAX];
790 Event event = EVENT_NULL;
791 int retval_sent = !daemonize;
793 FILE *dispatcher = NULL;
794 char *address_fn = NULL;
797 daemon_signal_init(SIGINT, SIGTERM, SIGCHLD, SIGHUP,0);
799 if (!(dispatcher = fork_dispatcher()))
802 if ((fd = open_socket(iface, hw_address)) < 0)
805 if ((iface_fd = iface_init(iface)) < 0)
808 if (drop_privs() < 0)
813 else if (iface_get_initial_state(&st) < 0)
821 p = AVAHI_IPDATA_DIR;
823 address_fn = avahi_strdup_printf(
824 "%s/%02x:%02x:%02x:%02x:%02x:%02x", p,
825 hw_address[0], hw_address[1],
826 hw_address[2], hw_address[3],
827 hw_address[4], hw_address[5]);
830 load_address(address_fn, &addr);
832 if (addr && !is_ll_address(addr)) {
833 daemon_log(LOG_WARNING, "Requested address %s is not from IPv4LL range 169.254/16, ignoring.", inet_ntop(AF_INET, &addr, buf, sizeof(buf)));
841 for (i = 0; i < ETHER_ADDRLEN; i++)
842 a += hw_address[i]*i;
844 addr = htonl(IPV4LL_NETWORK | (uint32_t) a);
847 set_state(st, 1, addr);
849 daemon_log(LOG_INFO, "Starting with address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf)));
851 if (state == STATE_SLEEPING)
852 daemon_log(LOG_INFO, "Routable address already assigned, sleeping.");
854 if (!retval_sent && (!wait_for_address || state == STATE_SLEEPING)) {
855 daemon_retval_send(0);
859 memset(pollfds, 0, sizeof(pollfds));
860 pollfds[FD_ARP].fd = fd;
861 pollfds[FD_ARP].events = POLLIN;
862 pollfds[FD_IFACE].fd = iface_fd;
863 pollfds[FD_IFACE].events = POLLIN;
864 pollfds[FD_SIGNAL].fd = daemon_signal_fd();
865 pollfds[FD_SIGNAL].events = POLLIN;
871 if (state == STATE_START) {
873 /* First, wait a random time */
874 set_state(STATE_WAITING_PROBE, 1, addr);
876 elapse_time(&next_wakeup, 0, PROBE_WAIT*1000);
877 next_wakeup_valid = 1;
879 } else if ((state == STATE_WAITING_PROBE && event == EVENT_TIMEOUT) ||
880 (state == STATE_PROBING && event == EVENT_TIMEOUT && n_iteration < PROBE_NUM-2)) {
883 out_packet = packet_new_probe(addr, hw_address, &out_packet_len);
884 set_state(STATE_PROBING, 0, addr);
886 elapse_time(&next_wakeup, PROBE_MIN*1000, (PROBE_MAX-PROBE_MIN)*1000);
887 next_wakeup_valid = 1;
889 } else if (state == STATE_PROBING && event == EVENT_TIMEOUT && n_iteration >= PROBE_NUM-2) {
891 /* Send the last probe */
892 out_packet = packet_new_probe(addr, hw_address, &out_packet_len);
893 set_state(STATE_WAITING_ANNOUNCE, 1, addr);
895 elapse_time(&next_wakeup, ANNOUNCE_WAIT*1000, 0);
896 next_wakeup_valid = 1;
898 } else if ((state == STATE_WAITING_ANNOUNCE && event == EVENT_TIMEOUT) ||
899 (state == STATE_ANNOUNCING && event == EVENT_TIMEOUT && n_iteration < ANNOUNCE_NUM-1)) {
901 /* Send announcement packet */
902 out_packet = packet_new_announcement(addr, hw_address, &out_packet_len);
903 set_state(STATE_ANNOUNCING, 0, addr);
905 elapse_time(&next_wakeup, ANNOUNCE_INTERVAL*1000, 0);
906 next_wakeup_valid = 1;
908 if (n_iteration == 0) {
909 if (do_callout(dispatcher, CALLOUT_BIND, iface, addr) < 0)
915 } else if ((state == STATE_ANNOUNCING && event == EVENT_TIMEOUT && n_iteration >= ANNOUNCE_NUM-1)) {
917 daemon_log(LOG_INFO, "Successfully claimed IP address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf)));
918 set_state(STATE_RUNNING, 0, addr);
920 next_wakeup_valid = 0;
922 save_address(address_fn, addr);
925 daemon_retval_send(0);
929 } else if (event == EVENT_PACKET) {
934 if (packet_parse(in_packet, in_packet_len, &info) < 0)
935 daemon_log(LOG_WARNING, "Failed to parse incoming ARP packet.");
939 if (info.sender_ip_address == addr) {
940 /* Normal conflict */
942 daemon_log(LOG_INFO, "Recieved conflicting normal ARP packet.");
943 } else if (state == STATE_WAITING_PROBE || state == STATE_PROBING || state == STATE_WAITING_ANNOUNCE) {
945 conflict = info.target_ip_address == addr && memcmp(hw_address, info.sender_hw_address, ETHER_ADDRLEN);
948 daemon_log(LOG_INFO, "Recieved conflicting probe ARP packet.");
953 if (state == STATE_RUNNING || state == STATE_ANNOUNCING)
954 if (do_callout(dispatcher, CALLOUT_CONFLICT, iface, addr) < 0)
957 /* Pick a new address */
958 addr = pick_addr(addr);
960 daemon_log(LOG_INFO, "Trying address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf)));
964 set_state(STATE_WAITING_PROBE, 1, addr);
966 if (n_conflict >= MAX_CONFLICTS) {
967 daemon_log(LOG_WARNING, "Got too many conflicts, rate limiting new probes.");
968 elapse_time(&next_wakeup, RATE_LIMIT_INTERVAL*1000, PROBE_WAIT*1000);
970 elapse_time(&next_wakeup, 0, PROBE_WAIT*1000);
972 next_wakeup_valid = 1;
974 DEBUG(daemon_log(LOG_DEBUG, "Ignoring irrelevant ARP packet."));
977 } else if (event == EVENT_ROUTABLE_ADDR_CONFIGURED) {
979 daemon_log(LOG_INFO, "A routable address has been configured.");
981 if (state == STATE_RUNNING || state == STATE_ANNOUNCING)
982 if (do_callout(dispatcher, CALLOUT_UNBIND, iface, addr) < 0)
986 daemon_retval_send(0);
990 set_state(STATE_SLEEPING, 1, addr);
991 next_wakeup_valid = 0;
993 } else if (event == EVENT_ROUTABLE_ADDR_UNCONFIGURED && state == STATE_SLEEPING && !force_bind) {
995 daemon_log(LOG_INFO, "No longer a routable address configured, restarting probe process.");
997 set_state(STATE_WAITING_PROBE, 1, addr);
999 elapse_time(&next_wakeup, 0, PROBE_WAIT*1000);
1000 next_wakeup_valid = 1;
1002 } else if (event == EVENT_REFRESH_REQUEST && state == STATE_RUNNING && !force_bind) {
1004 /* The user requested a reannouncing of the address by a SIGHUP */
1005 daemon_log(LOG_INFO, "Reannouncing address.");
1007 /* Send announcement packet */
1008 out_packet = packet_new_announcement(addr, hw_address, &out_packet_len);
1009 set_state(STATE_ANNOUNCING, 1, addr);
1011 elapse_time(&next_wakeup, ANNOUNCE_INTERVAL*1000, 0);
1012 next_wakeup_valid = 1;
1016 DEBUG(daemon_log(LOG_DEBUG, "sending..."));
1018 if (send_packet(fd, iface, out_packet, out_packet_len) < 0)
1021 avahi_free(out_packet);
1026 avahi_free(in_packet);
1033 if (next_wakeup_valid) {
1034 usec = avahi_age(&next_wakeup);
1035 timeout = usec < 0 ? (int) (-usec/1000) : 0;
1038 DEBUG(daemon_log(LOG_DEBUG, "sleeping %ims", timeout));
1040 while ((r = poll(pollfds, FD_MAX, timeout)) < 0 && errno == EINTR)
1044 daemon_log(LOG_ERR, "poll() failed: %s", strerror(r));
1046 } else if (r == 0) {
1047 event = EVENT_TIMEOUT;
1048 next_wakeup_valid = 0;
1052 if (pollfds[FD_ARP].revents) {
1054 if (pollfds[FD_ARP].revents == POLLERR) {
1055 /* The interface is probably down, let's recreate our socket */
1059 if ((fd = open_socket(iface, hw_address)) < 0)
1062 pollfds[FD_ARP].fd = fd;
1066 assert(pollfds[FD_ARP].revents == POLLIN);
1068 if (recv_packet(fd, &in_packet, &in_packet_len) < 0)
1072 event = EVENT_PACKET;
1076 if (event == EVENT_NULL &&
1077 pollfds[FD_IFACE].revents) {
1079 assert(pollfds[FD_IFACE].revents == POLLIN);
1081 if (iface_process(&event) < 0)
1085 if (event == EVENT_NULL &&
1086 pollfds[FD_SIGNAL].revents) {
1089 assert(pollfds[FD_SIGNAL].revents == POLLIN);
1091 if ((sig = daemon_signal_next()) <= 0) {
1092 daemon_log(LOG_ERR, "daemon_signal_next() failed");
1099 daemon_log(LOG_INFO, "Got %s, quitting.", sig == SIGINT ? "SIGINT" : "SIGTERM");
1104 waitpid(-1, NULL, WNOHANG);
1108 event = EVENT_REFRESH_REQUEST;
1120 if (state == STATE_RUNNING || state == STATE_ANNOUNCING)
1121 do_callout(dispatcher, CALLOUT_STOP, iface, addr);
1123 avahi_free(out_packet);
1124 avahi_free(in_packet);
1132 if (daemonize && !retval_sent)
1133 daemon_retval_send(ret);
1139 avahi_free(address_fn);
1145 static void help(FILE *f, const char *a0) {
1147 "%s [options] INTERFACE\n"
1148 " -h --help Show this help\n"
1149 " -D --daemonize Daemonize after startup\n"
1150 " -s --syslog Write log messages to syslog(3) instead of STDERR\n"
1151 " -k --kill Kill a running daemon\n"
1152 " -r --refresh Request a running daemon to refresh it's IP address\n"
1153 " -c --check Return 0 if a daemon is already running\n"
1154 " -V --version Show version\n"
1155 " -S --start=ADDRESS Start with this address from the IPv4LL range\n"
1157 " -w --wait Wait until an address has been acquired before\n"
1159 " --force-bind Assign an IPv4LL address even if routable address\n"
1160 " is already assigned\n"
1161 " --no-drop-root Don't drop privileges\n"
1163 " --no-chroot Don't chroot()\n"
1165 " --no-proc-title Don't modify process title\n"
1166 " --debug Increase verbosity\n",
1170 static int parse_command_line(int argc, char *argv[]) {
1174 OPTION_NO_PROC_TITLE = 256,
1177 OPTION_NO_DROP_ROOT,
1183 static const struct option long_options[] = {
1184 { "help", no_argument, NULL, 'h' },
1185 { "daemonize", no_argument, NULL, 'D' },
1186 { "syslog", no_argument, NULL, 's' },
1187 { "kill", no_argument, NULL, 'k' },
1188 { "refresh", no_argument, NULL, 'r' },
1189 { "check", no_argument, NULL, 'c' },
1190 { "version", no_argument, NULL, 'V' },
1191 { "start", required_argument, NULL, 'S' },
1192 { "wait", no_argument, NULL, 'w' },
1193 { "force-bind", no_argument, NULL, OPTION_FORCE_BIND },
1194 { "no-drop-root", no_argument, NULL, OPTION_NO_DROP_ROOT },
1196 { "no-chroot", no_argument, NULL, OPTION_NO_CHROOT },
1198 { "no-proc-title", no_argument, NULL, OPTION_NO_PROC_TITLE },
1199 { "debug", no_argument, NULL, OPTION_DEBUG },
1200 { NULL, 0, NULL, 0 }
1204 while ((c = getopt_long(argc, argv, "hDskrcVS:w", long_options, NULL)) >= 0) {
1211 command = DAEMON_HELP;
1217 command = DAEMON_KILL;
1220 command = DAEMON_VERSION;
1223 command = DAEMON_REFRESH;
1226 command = DAEMON_CHECK;
1230 if ((start_address = inet_addr(optarg)) == (uint32_t) -1) {
1231 fprintf(stderr, "Failed to parse IP address '%s'.", optarg);
1236 wait_for_address = 1;
1239 case OPTION_NO_PROC_TITLE:
1240 modify_proc_title = 0;
1247 case OPTION_FORCE_BIND:
1251 case OPTION_NO_DROP_ROOT:
1256 case OPTION_NO_CHROOT:
1262 fprintf(stderr, "Invalid command line argument: %c\n", c);
1267 if (command == DAEMON_RUN ||
1268 command == DAEMON_KILL ||
1269 command == DAEMON_REFRESH ||
1270 command == DAEMON_CHECK) {
1272 if (optind >= argc) {
1273 fprintf(stderr, "Missing interface name.\n");
1277 interface_name = avahi_strdup(argv[optind++]);
1280 if (optind != argc) {
1281 fprintf(stderr, "Too many arguments\n");
1288 static const char* pid_file_proc(void) {
1289 return pid_file_name;
1292 int main(int argc, char*argv[]) {
1294 char *log_ident = NULL;
1296 signal(SIGPIPE, SIG_IGN);
1298 if ((argv0 = strrchr(argv[0], '/')))
1299 argv0 = avahi_strdup(argv0 + 1);
1301 argv0 = avahi_strdup(argv[0]);
1303 daemon_log_ident = argv0;
1305 if (parse_command_line(argc, argv) < 0)
1308 if (modify_proc_title)
1309 avahi_init_proc_title(argc, argv);
1311 daemon_log_ident = log_ident = avahi_strdup_printf("%s(%s)", argv0, interface_name);
1312 daemon_pid_file_proc = pid_file_proc;
1313 pid_file_name = avahi_strdup_printf(AVAHI_RUNTIME_DIR"/avahi-autoipd.%s.pid", interface_name);
1315 if (command == DAEMON_RUN) {
1321 if ((ifindex = if_nametoindex(interface_name)) <= 0) {
1322 daemon_log(LOG_ERR, "Failed to get index for interface name '%s': %s", interface_name, strerror(errno));
1326 if (getuid() != 0) {
1327 daemon_log(LOG_ERR, "This program is intended to be run as root.");
1331 if ((pid = daemon_pid_file_is_running()) >= 0) {
1332 daemon_log(LOG_ERR, "Daemon already running on PID %u", pid);
1337 daemon_retval_init();
1339 if ((pid = daemon_fork()) < 0)
1341 else if (pid != 0) {
1345 if ((ret = daemon_retval_wait(20)) < 0) {
1346 daemon_log(LOG_ERR, "Could not receive return value from daemon process.");
1357 if (use_syslog || daemonize)
1358 daemon_log_use = DAEMON_LOG_SYSLOG;
1362 if (daemon_pid_file_create() < 0) {
1363 daemon_log(LOG_ERR, "Failed to create PID file: %s", strerror(errno));
1366 daemon_retval_send(1);
1371 avahi_set_proc_title(argv0, "%s: [%s] starting up", argv0, interface_name);
1373 if (loop(ifindex, start_address) < 0)
1377 } else if (command == DAEMON_HELP) {
1378 help(stdout, argv0);
1381 } else if (command == DAEMON_VERSION) {
1382 printf("%s "PACKAGE_VERSION"\n", argv0);
1385 } else if (command == DAEMON_KILL) {
1386 if (daemon_pid_file_kill_wait(SIGTERM, 5) < 0) {
1387 daemon_log(LOG_WARNING, "Failed to kill daemon: %s", strerror(errno));
1392 } else if (command == DAEMON_REFRESH) {
1393 if (daemon_pid_file_kill(SIGHUP) < 0) {
1394 daemon_log(LOG_WARNING, "Failed to kill daemon: %s", strerror(errno));
1399 } else if (command == DAEMON_CHECK)
1400 r = (daemon_pid_file_is_running() >= 0) ? 0 : 1;
1406 daemon_retval_done();
1409 daemon_pid_file_remove();
1411 avahi_free(log_ident);
1412 avahi_free(pid_file_name);
1414 avahi_free(interface_name);