From: Lennart Poettering Date: Thu, 31 Aug 2006 00:16:27 +0000 (+0000) Subject: implement command line parsing, signal handling, daemonization X-Git-Url: https://git.meshlink.io/?a=commitdiff_plain;h=5ea98f8caf0e163ad1f51039b8a2d13e3fe0e86c;p=catta implement command line parsing, signal handling, daemonization git-svn-id: file:///home/lennart/svn/public/avahi/trunk@1290 941a03a8-eaeb-0310-b9a0-b1bbd8fe43fe --- diff --git a/avahi-autoipd/Makefile.am b/avahi-autoipd/Makefile.am index adfe70d..c553470 100644 --- a/avahi-autoipd/Makefile.am +++ b/avahi-autoipd/Makefile.am @@ -24,7 +24,9 @@ AM_CFLAGS= \ -I$(top_srcdir) # This cool debug trap works on i386/gcc only -AM_CFLAGS+='-DDEBUG_TRAP=__asm__("int $$3")' +AM_CFLAGS+='-DDEBUG_TRAP=__asm__("int $$3")' \ + -DAVAHI_RUNTIME_DIR=\"$(avahi_runtime_dir)/\" \ + -DAVAHI_DNSCONF_SCRIPT=\"$(pkgsysconfdir)/avahi-autoipd.action\" sbin_PROGRAMS = avahi-autoipd diff --git a/avahi-autoipd/main.c b/avahi-autoipd/main.c index feb88ee..04c3111 100644 --- a/avahi-autoipd/main.c +++ b/avahi-autoipd/main.c @@ -39,6 +39,10 @@ #include #include #include +#include +#include +#include +#include #include #include @@ -95,8 +99,41 @@ static State state = STATE_START; static int n_iteration = 0; static int n_conflict = 0; +static char *interface_name = NULL; +static char *pid_file_name = NULL; +static uint32_t start_address = 0; +static char *argv0 = NULL; +static int daemonize = 0; +static int wait_for_address = 0; +static int use_syslog = 0; +static int debug = 0; +static int modify_proc_title = 1; + +static enum { + DAEMON_RUN, + DAEMON_KILL, + DAEMON_REFRESH, + DAEMON_VERSION, + DAEMON_HELP, + DAEMON_CHECK +} command = DAEMON_RUN; + +typedef enum CalloutEvent { + CALLOUT_BIND, + CALLOUT_CONFLICT, + CALLOUT_UNBIND, + CALLOUT_STOP, + CALLOUT_MAX +} CalloutEvent; + #define RANDOM_DEVICE "/dev/urandom" +#define DEBUG(x) do {\ +if (debug) { \ + x; \ +} \ +} while (0) + static void init_rand_seed(void) { int fd; unsigned seed = 0; @@ -204,7 +241,7 @@ static int packet_parse(const void *data, size_t packet_len, ArpPacketInfo *info return 0; } -static void set_state(State st, int reset_counter) { +static void set_state(State st, int reset_counter, uint32_t address) { const char* const state_table[] = { [STATE_START] = "START", [STATE_WAITING_PROBE] = "WAITING_PROBE", @@ -214,30 +251,45 @@ static void set_state(State st, int reset_counter) { [STATE_RUNNING] = "RUNNING", [STATE_SLEEPING] = "SLEEPING" }; + char buf[64]; assert(st < STATE_MAX); if (st == state && !reset_counter) { n_iteration++; - daemon_log(LOG_DEBUG, "State iteration %s-%i", state_table[state], n_iteration); + DEBUG(daemon_log(LOG_DEBUG, "State iteration %s-%i", state_table[state], n_iteration)); } else { - daemon_log(LOG_DEBUG, "State transition %s-%i -> %s-0", state_table[state], n_iteration, state_table[st]); + DEBUG(daemon_log(LOG_DEBUG, "State transition %s-%i -> %s-0", state_table[state], n_iteration, state_table[st])); state = st; n_iteration = 0; } -} -static int add_address(int iface, uint32_t addr) { - char buf[64]; - - daemon_log(LOG_INFO, "Configuring address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf))); - return 0; + if (modify_proc_title) { + if (state == STATE_SLEEPING) + avahi_set_proc_title("%s: sleeping", argv0); + else if (state == STATE_ANNOUNCING) + avahi_set_proc_title("%s: announcing %s", argv0, inet_ntop(AF_INET, &address, buf, sizeof(buf))); + else if (state == STATE_RUNNING) + avahi_set_proc_title("%s: bound %s", argv0, inet_ntop(AF_INET, &address, buf, sizeof(buf))); + else + avahi_set_proc_title("%s: probing %s", argv0, inet_ntop(AF_INET, &address, buf, sizeof(buf))); + } } -static int remove_address(int iface, uint32_t addr) { - char buf[64]; +static int do_callout(CalloutEvent event, int iface, uint32_t addr) { + char buf[64], ifname[IFNAMSIZ]; + const char * const event_table[CALLOUT_MAX] = { + [CALLOUT_BIND] = "BIND", + [CALLOUT_CONFLICT] = "CONFLICT", + [CALLOUT_UNBIND] = "UNBIND", + [CALLOUT_STOP] = "STOP" + }; + + daemon_log(LOG_INFO, "Callout %s, address %s on interface %s", + event_table[event], + inet_ntop(AF_INET, &addr, buf, sizeof(buf)), + if_indextoname(iface, ifname)); - daemon_log(LOG_INFO, "Unconfiguring address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf))); return 0; } @@ -363,7 +415,8 @@ static int loop(int iface, uint32_t addr) { enum { FD_ARP, FD_IFACE, - FD_MAX + FD_SIGNAL, + FD_MAX, }; int fd = -1, ret = -1; @@ -378,6 +431,10 @@ static int loop(int iface, uint32_t addr) { struct pollfd pollfds[FD_MAX]; int iface_fd; Event event = EVENT_NULL; + int retval_sent = !daemonize; + State st; + + daemon_signal_init(SIGINT, SIGTERM, SIGCHLD, SIGHUP,0); if ((fd = open_socket(iface, hw_address)) < 0) goto fail; @@ -385,9 +442,9 @@ static int loop(int iface, uint32_t addr) { if ((iface_fd = iface_init(iface)) < 0) goto fail; - if (iface_get_initial_state(&state) < 0) + if (iface_get_initial_state(&st) < 0) goto fail; - + if (addr && !is_ll_address(addr)) { daemon_log(LOG_WARNING, "Requested address %s is not from IPv4LL range 169.254/16, ignoring.", inet_ntop(AF_INET, &addr, buf, sizeof(buf))); addr = 0; @@ -403,16 +460,25 @@ static int loop(int iface, uint32_t addr) { addr = htonl(IPV4LL_NETWORK | (uint32_t) a); } + set_state(st, 1, addr); + daemon_log(LOG_INFO, "Starting with address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf))); if (state == STATE_SLEEPING) daemon_log(LOG_INFO, "Routable address already assigned, sleeping."); + if (!retval_sent && (!wait_for_address || state == STATE_SLEEPING)) { + daemon_retval_send(0); + retval_sent = 1; + } + memset(pollfds, 0, sizeof(pollfds)); pollfds[FD_ARP].fd = fd; pollfds[FD_ARP].events = POLLIN; pollfds[FD_IFACE].fd = iface_fd; pollfds[FD_IFACE].events = POLLIN; + pollfds[FD_SIGNAL].fd = daemon_signal_fd(); + pollfds[FD_SIGNAL].events = POLLIN; for (;;) { int r, timeout; @@ -421,7 +487,7 @@ static int loop(int iface, uint32_t addr) { if (state == STATE_START) { /* First, wait a random time */ - set_state(STATE_WAITING_PROBE, 1); + set_state(STATE_WAITING_PROBE, 1, addr); elapse_time(&next_wakeup, 0, PROBE_WAIT*1000); next_wakeup_valid = 1; @@ -431,7 +497,7 @@ static int loop(int iface, uint32_t addr) { /* Send a probe */ out_packet = packet_new_probe(addr, hw_address, &out_packet_len); - set_state(STATE_PROBING, 0); + set_state(STATE_PROBING, 0, addr); elapse_time(&next_wakeup, PROBE_MIN*1000, (PROBE_MAX-PROBE_MIN)*1000); next_wakeup_valid = 1; @@ -440,7 +506,7 @@ static int loop(int iface, uint32_t addr) { /* Send the last probe */ out_packet = packet_new_probe(addr, hw_address, &out_packet_len); - set_state(STATE_WAITING_ANNOUNCE, 1); + set_state(STATE_WAITING_ANNOUNCE, 1, addr); elapse_time(&next_wakeup, ANNOUNCE_WAIT*1000, 0); next_wakeup_valid = 1; @@ -450,20 +516,25 @@ static int loop(int iface, uint32_t addr) { /* Send announcement packet */ out_packet = packet_new_announcement(addr, hw_address, &out_packet_len); - set_state(STATE_ANNOUNCING, 0); + set_state(STATE_ANNOUNCING, 0, addr); elapse_time(&next_wakeup, ANNOUNCE_INTERVAL*1000, 0); next_wakeup_valid = 1; if (n_iteration == 0) { - add_address(iface, addr); + do_callout(CALLOUT_BIND, iface, addr); n_conflict = 0; + + if (!retval_sent) { + daemon_retval_send(0); + retval_sent = 1; + } } } else if ((state == STATE_ANNOUNCING && event == EVENT_TIMEOUT && n_iteration >= ANNOUNCE_NUM-1)) { daemon_log(LOG_INFO, "Successfully claimed IP address %s", inet_ntop(AF_INET, &addr, buf, sizeof(buf))); - set_state(STATE_RUNNING, 0); + set_state(STATE_RUNNING, 0, addr); next_wakeup_valid = 0; @@ -490,7 +561,7 @@ static int loop(int iface, uint32_t addr) { if (conflict) { if (state == STATE_RUNNING || state == STATE_ANNOUNCING) - remove_address(iface, addr); + do_callout(CALLOUT_CONFLICT, iface, addr); /* Pick a new address */ addr = pick_addr(addr); @@ -499,7 +570,7 @@ static int loop(int iface, uint32_t addr) { n_conflict++; - set_state(STATE_WAITING_PROBE, 1); + set_state(STATE_WAITING_PROBE, 1, addr); if (n_conflict >= MAX_CONFLICTS) { daemon_log(LOG_WARNING, "Got too many conflicts, rate limiting new probes."); @@ -509,7 +580,7 @@ static int loop(int iface, uint32_t addr) { next_wakeup_valid = 1; } else - daemon_log(LOG_DEBUG, "Ignoring ARP packet."); + DEBUG(daemon_log(LOG_DEBUG, "Ignoring irrelevant ARP packet.")); } } else if (event == EVENT_ROUTABLE_ADDR_CONFIGURED) { @@ -517,24 +588,40 @@ static int loop(int iface, uint32_t addr) { daemon_log(LOG_INFO, "A routable address has been configured."); if (state == STATE_RUNNING || state == STATE_ANNOUNCING) - remove_address(iface, addr); + do_callout(CALLOUT_UNBIND, iface, addr); - set_state(STATE_SLEEPING, 1); + if (!retval_sent) { + daemon_retval_send(0); + retval_sent = 1; + } + + set_state(STATE_SLEEPING, 1, addr); next_wakeup_valid = 0; } else if (event == EVENT_ROUTABLE_ADDR_UNCONFIGURED && state == STATE_SLEEPING) { daemon_log(LOG_INFO, "No longer a routable address configured, restarting probe process."); - set_state(STATE_WAITING_PROBE, 1); + set_state(STATE_WAITING_PROBE, 1, addr); elapse_time(&next_wakeup, 0, PROBE_WAIT*1000); next_wakeup_valid = 1; + + } else if (event == EVENT_REFRESH_REQUEST && state == STATE_RUNNING) { + + /* The user requested a reannouncing of the address by a SIGHUP */ + daemon_log(LOG_INFO, "Reannouncing address."); + /* Send announcement packet */ + out_packet = packet_new_announcement(addr, hw_address, &out_packet_len); + set_state(STATE_ANNOUNCING, 1, addr); + + elapse_time(&next_wakeup, ANNOUNCE_INTERVAL*1000, 0); + next_wakeup_valid = 1; } if (out_packet) { - daemon_log(LOG_DEBUG, "sending..."); + DEBUG(daemon_log(LOG_DEBUG, "sending...")); if (send_packet(fd, iface, out_packet, out_packet_len) < 0) goto fail; @@ -556,14 +643,14 @@ static int loop(int iface, uint32_t addr) { timeout = usec < 0 ? (int) (-usec/1000) : 0; } - daemon_log(LOG_DEBUG, "sleeping %ims", timeout); + DEBUG(daemon_log(LOG_DEBUG, "sleeping %ims", timeout)); while ((r = poll(pollfds, FD_MAX, timeout)) < 0 && errno == EINTR) ; if (r < 0) { daemon_log(LOG_ERR, "poll() failed: %s", strerror(r)); - break; + goto fail; } else if (r == 0) { event = EVENT_TIMEOUT; next_wakeup_valid = 0; @@ -583,6 +670,34 @@ static int loop(int iface, uint32_t addr) { if (iface_process(&event) < 0) goto fail; } + + if (event == EVENT_NULL && + pollfds[FD_SIGNAL].revents == POLLIN) { + + int sig; + + if ((sig = daemon_signal_next()) <= 0) { + daemon_log(LOG_ERR, "daemon_signal_next() failed"); + goto fail; + } + + switch(sig) { + case SIGINT: + case SIGTERM: + daemon_log(LOG_INFO, "Got %s, quitting.", sig == SIGINT ? "SIGINT" : "SIGTERM"); + ret = 0; + goto fail; + + case SIGCHLD: + waitpid(-1, NULL, WNOHANG); + break; + + case SIGHUP: + event = EVENT_REFRESH_REQUEST; + break; + } + + } } } @@ -590,6 +705,9 @@ static int loop(int iface, uint32_t addr) { fail: + if (state == STATE_RUNNING || state == STATE_ANNOUNCING) + do_callout(CALLOUT_STOP, iface, addr); + avahi_free(out_packet); avahi_free(in_packet); @@ -598,74 +716,250 @@ fail: if (iface_fd >= 0) iface_done(); + + if (daemonize && !retval_sent) + daemon_retval_send(ret); return ret; } -static int get_ifindex(const char *name) { - int fd = -1; - struct ifreq ifreq; - if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) { - daemon_log(LOG_ERR, "socket() failed: %s", strerror(errno)); - goto fail; - } +static void help(FILE *f, const char *a0) { + fprintf(f, + "%s [options] INTERFACE\n" + " -h --help Show this help\n" + " -D --daemonize Daemonize after startup\n" + " -s --syslog Write log messages to syslog(3) instead of STDERR\n" + " -k --kill Kill a running daemon\n" + " -r --refresh Request a running daemon to refresh it's IP address\n" + " -c --check Return 0 if a daemon is already running\n" + " -V --version Show version\n" + " -S --start=ADDRESS Start with this address from the IPv4LL range 169.254.0.0/16\n" + " -w --wait Wait until an address has been acquired before daemonizing\n" + " --no-proc-title Don't modify process title\n" + " --debug Increase verbosity\n", + a0); +} + +static int parse_command_line(int argc, char *argv[]) { + int c; + + enum { + OPTION_NO_PROC_TITLE = 256, + OPTION_DEBUG + }; + + static const struct option long_options[] = { + { "help", no_argument, NULL, 'h' }, + { "daemonize", no_argument, NULL, 'D' }, + { "syslog", no_argument, NULL, 's' }, + { "kill", no_argument, NULL, 'k' }, + { "refresh", no_argument, NULL, 'r' }, + { "check", no_argument, NULL, 'c' }, + { "version", no_argument, NULL, 'V' }, + { "start", required_argument, NULL, 'S' }, + { "wait", no_argument, NULL, 'w' }, + { "no-proc-title", no_argument, NULL, OPTION_NO_PROC_TITLE }, + { "debug", no_argument, NULL, OPTION_DEBUG }, + { NULL, 0, NULL, 0 } + }; - memset(&ifreq, 0, sizeof(ifreq)); - strncpy(ifreq.ifr_name, name, IFNAMSIZ-1); - ifreq.ifr_name[IFNAMSIZ-1] = 0; + opterr = 0; + while ((c = getopt_long(argc, argv, "hDkVrcS:", long_options, NULL)) >= 0) { + + switch(c) { + case 's': + use_syslog = 1; + break; + case 'h': + command = DAEMON_HELP; + break; + case 'D': + daemonize = 1; + break; + case 'k': + command = DAEMON_KILL; + break; + case 'V': + command = DAEMON_VERSION; + break; + case 'r': + command = DAEMON_REFRESH; + break; + case 'c': + command = DAEMON_CHECK; + break; + case 'S': + + if ((start_address = inet_addr(optarg)) == (uint32_t) -1) { + fprintf(stderr, "Failed to parse IP address '%s'.", optarg); + return -1; + } + break; + case 'w': + wait_for_address = 1; + break; + + case OPTION_NO_PROC_TITLE: + modify_proc_title = 0; + break; - if (ioctl(fd, SIOCGIFINDEX, &ifreq) < 0) { - daemon_log(LOG_ERR, "SIOCGIFINDEX failed: %s", strerror(errno)); - goto fail; + case OPTION_DEBUG: + debug = 1; + break; + + default: + fprintf(stderr, "Invalid command line argument: %c\n", c); + return -1; + } } - return ifreq.ifr_ifindex; + if (command == DAEMON_RUN || + command == DAEMON_KILL || + command == DAEMON_REFRESH || + command == DAEMON_CHECK) { -fail: + if (optind >= argc) { + fprintf(stderr, "Missing interface name.\n"); + return -1; + } - if (fd >= 0) - close(fd); - - return -1; + interface_name = argv[optind++]; + } + + if (optind != argc) { + fprintf(stderr, "Too many arguments\n"); + return -1; + } + + return 0; +} + +static const char* pid_file_proc(void) { + return pid_file_name; } int main(int argc, char*argv[]) { - int ret = 1; - int ifindex; - uint32_t addr = 0; + int r = 1; + int wrote_pid_file = 0; avahi_init_proc_title(argc, argv); - - init_rand_seed(); - if ((ifindex = get_ifindex(argc >= 2 ? argv[1] : "eth0")) < 0) - goto fail; + if ((argv0 = strrchr(argv[0], '/'))) + argv0++; + else + argv0 = argv[0]; - if (argc >= 3) - addr = inet_addr(argv[2]); - - if (loop(ifindex, addr) < 0) - goto fail; + daemon_pid_file_ident = daemon_log_ident = argv0; + daemon_pid_file_proc = pid_file_proc; - ret = 0; + if (parse_command_line(argc, argv) < 0) + goto finish; + pid_file_name = avahi_strdup_printf(AVAHI_RUNTIME_DIR"/avahi-autoipd.%s.pid", interface_name); + + if (command == DAEMON_RUN) { + pid_t pid; + int ifindex; + + init_rand_seed(); + + if ((ifindex = if_nametoindex(interface_name)) <= 0) { + daemon_log(LOG_ERR, "Failed to get index for interface name '%s': %s", interface_name, strerror(errno)); + goto finish; + } + + if (getuid() != 0) { + daemon_log(LOG_ERR, "This program is intended to be run as root."); + goto finish; + } + + if ((pid = daemon_pid_file_is_running()) >= 0) { + daemon_log(LOG_ERR, "Daemon already running on PID %u", pid); + goto finish; + } + + if (daemonize) { + daemon_retval_init(); + + if ((pid = daemon_fork()) < 0) + goto finish; + else if (pid != 0) { + int ret; + /** Parent **/ + + if ((ret = daemon_retval_wait(20)) < 0) { + daemon_log(LOG_ERR, "Could not receive return value from daemon process."); + goto finish; + } + + r = ret; + goto finish; + } + + /* Child */ + } + + if (use_syslog || daemonize) + daemon_log_use = DAEMON_LOG_SYSLOG; + + chdir("/"); + + if (daemon_pid_file_create() < 0) { + daemon_log(LOG_ERR, "Failed to create PID file: %s", strerror(errno)); + + if (daemonize) + daemon_retval_send(1); + goto finish; + } else + wrote_pid_file = 1; + + if (loop(ifindex, start_address) < 0) + goto finish; + + r = 0; + } else if (command == DAEMON_HELP) { + help(stdout, argv0); + + r = 0; + } else if (command == DAEMON_VERSION) { + printf("%s "PACKAGE_VERSION"\n", argv0); + + r = 0; + } else if (command == DAEMON_KILL) { + if (daemon_pid_file_kill_wait(SIGTERM, 5) < 0) { + daemon_log(LOG_WARNING, "Failed to kill daemon: %s", strerror(errno)); + goto finish; + } + + r = 0; + } else if (command == DAEMON_REFRESH) { + if (daemon_pid_file_kill(SIGHUP) < 0) { + daemon_log(LOG_WARNING, "Failed to kill daemon: %s", strerror(errno)); + goto finish; + } + + r = 0; + } else if (command == DAEMON_CHECK) + r = (daemon_pid_file_is_running() >= 0) ? 0 : 1; + + +finish: + + if (daemonize) + daemon_retval_done(); -fail: - - return ret; + if (wrote_pid_file) + daemon_pid_file_remove(); + + return r; } /* TODO: -- man page -- user script - chroot/drop privs/caps -- daemonize -- defend -- signals +- user script - store last used address -- cmdline -- setproctitle +- man page */ diff --git a/avahi-autoipd/main.h b/avahi-autoipd/main.h index 61d5ed6..adadc99 100644 --- a/avahi-autoipd/main.h +++ b/avahi-autoipd/main.h @@ -28,6 +28,7 @@ typedef enum Event { EVENT_TIMEOUT, EVENT_ROUTABLE_ADDR_CONFIGURED, EVENT_ROUTABLE_ADDR_UNCONFIGURED, + EVENT_REFRESH_REQUEST } Event; typedef enum State {