+++ /dev/null
-/***
- This file is part of avahi.
-
- avahi is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as
- published by the Free Software Foundation; either version 2.1 of the
- License, or (at your option) any later version.
-
- avahi 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 Lesser General
- Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with avahi; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
- USA.
-***/
-
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
-#include <fcntl.h>
-#include <unistd.h>
-#include <sys/select.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <errno.h>
-#include <string.h>
-#include <stdio.h>
-#include <sys/ioctl.h>
-#include <net/if.h>
-#include <signal.h>
-#include <sys/wait.h>
-#include <getopt.h>
-#include <assert.h>
-#include <inttypes.h>
-#include <stdlib.h>
-
-#include <avahi-common/llist.h>
-#include <avahi-common/malloc.h>
-#include <avahi-common/address.h>
-
-#include <libdaemon/dfork.h>
-#include <libdaemon/dsignal.h>
-#include <libdaemon/dlog.h>
-#include <libdaemon/dpid.h>
-#include <libdaemon/dexec.h>
-
-#define BROWSE_DNS_SERVERS "BROWSE-DNS-SERVERS\n"
-
-#define ENV_INTERFACE_DNS_SERVERS "AVAHI_INTERFACE_DNS_SERVERS"
-#define ENV_DNS_SERVERS "AVAHI_DNS_SERVERS"
-#define ENV_INTERFACE "AVAHI_INTERFACE"
-
-static enum {
- ACKWAIT,
- BROWSING
-} state = ACKWAIT;
-
-static enum {
- DAEMON_RUN,
- DAEMON_KILL,
- DAEMON_REFRESH,
- DAEMON_VERSION,
- DAEMON_HELP,
- DAEMON_CHECK
-} command = DAEMON_RUN;
-
-static int quit = 0;
-static int daemonize = 0;
-static int use_syslog = 0;
-
-#if !HAVE_DECL_ENVIRON
-extern char **environ;
-#endif
-
-typedef struct DNSServerInfo DNSServerInfo;
-
-struct DNSServerInfo {
- AvahiIfIndex interface;
- AvahiProtocol protocol;
- char *address;
- AVAHI_LLIST_FIELDS(DNSServerInfo, servers);
-};
-
-static AVAHI_LLIST_HEAD(DNSServerInfo, servers);
-
-static void server_info_free(DNSServerInfo *i) {
- assert(i);
-
- avahi_free(i->address);
-
- AVAHI_LLIST_REMOVE(DNSServerInfo, servers, servers, i);
- avahi_free(i);
-}
-
-static DNSServerInfo* get_server_info(AvahiIfIndex interface, AvahiProtocol protocol, const char *address) {
- DNSServerInfo *i;
- assert(address);
-
- for (i = servers; i; i = i->servers_next)
- if (i->interface == interface &&
- i->protocol == protocol &&
- strcmp(i->address, address) == 0)
- return i;
-
- return NULL;
-}
-
-static DNSServerInfo* new_server_info(AvahiIfIndex interface, AvahiProtocol protocol, const char *address) {
- DNSServerInfo *i;
-
- assert(address);
-
- i = avahi_new(DNSServerInfo, 1);
- i->interface = interface;
- i->protocol = protocol;
- i->address = avahi_strdup(address);
-
- AVAHI_LLIST_PREPEND(DNSServerInfo, servers, servers, i);
-
- return i;
-}
-
-static int set_cloexec(int fd) {
- int n;
-
- assert(fd >= 0);
-
- if ((n = fcntl(fd, F_GETFD)) < 0)
- return -1;
-
- if (n & FD_CLOEXEC)
- return 0;
-
- return fcntl(fd, F_SETFD, n|FD_CLOEXEC);
-}
-
-static int open_socket(void) {
- int fd = -1;
- struct sockaddr_un sa;
-
- if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
- daemon_log(LOG_ERR, "socket(): %s", strerror(errno));
- goto fail;
- }
-
- if (set_cloexec(fd) < 0) {
- daemon_log(LOG_ERR, "fcntl(): %s", strerror(errno));
- goto fail;
- }
-
- memset(&sa, 0, sizeof(sa));
- sa.sun_family = AF_UNIX;
- strncpy(sa.sun_path, AVAHI_SOCKET, sizeof(sa.sun_path)-1);
- sa.sun_path[sizeof(sa.sun_path)-1] = 0;
-
- if (connect(fd, (struct sockaddr*) &sa, sizeof(sa)) < 0) {
- daemon_log(LOG_ERR, "connect(): %s", strerror(errno));
- daemon_log(LOG_INFO, "Failed to connect to the daemon. This probably means that you");
- daemon_log(LOG_INFO, "didn't start avahi-daemon before avahi-dnsconfd.");
- goto fail;
- }
-
- return fd;
-
-fail:
- if (fd >= 0)
- close(fd);
-
- return -1;
-}
-
-static ssize_t loop_write(int fd, const void*data, size_t size) {
-
- ssize_t ret = 0;
- assert(fd >= 0 && data && size);
-
- while (size > 0) {
- ssize_t r;
-
- if ((r = write(fd, data, size)) < 0)
- return r;
-
- if (r == 0)
- break;
-
- ret += r;
- data = (const uint8_t*) data + r;
- size -= r;
- }
-
- return ret;
-}
-
-static char *concat_dns_servers(AvahiIfIndex interface) {
- DNSServerInfo *i;
- char *r = NULL;
-
- for (i = servers; i; i = i->servers_next)
- if (i->interface == interface || interface <= 0) {
- DNSServerInfo *j;
- char *t;
-
- /* Filter out double entries */
- for (j = servers; j != i; j = j->servers_next)
- if (j->interface == interface || interface <= 0)
- if (strcmp(i->address, j->address) == 0)
- break;
-
- if (j != i)
- continue;
-
- if (!r)
- t = avahi_strdup(i->address);
- else
- t = avahi_strdup_printf("%s %s", r, i->address);
-
- avahi_free(r);
- r = t;
- }
-
- return r;
-}
-
-static void set_env(const char *name, const char *value) {
- char **e;
- size_t l;
-
- assert(name);
- assert(value);
-
- l = strlen(name);
-
- for (e = environ; *e; e++) {
- /* Search for the variable */
- if (strlen(*e) < l+1)
- continue;
-
- if (strncmp(*e, name, l) != 0 || (*e)[l] != '=')
- continue;
-
- /* We simply free the record, sicne we know that we created it previously */
- avahi_free(*e);
- *e = avahi_strdup_printf("%s=%s", name, value);
- return;
- }
-
- assert(0);
-}
-
-static void run_script(int new, AvahiIfIndex interface, AvahiProtocol protocol, const char *address) {
- char *p;
- int ret;
- char ia[16], pa[16];
- char name[IF_NAMESIZE];
-
- assert(interface > 0);
-
- if (!if_indextoname(interface, name))
- return;
-
- p = concat_dns_servers(interface);
- set_env(ENV_INTERFACE_DNS_SERVERS, p ? p : "");
- avahi_free(p);
-
- p = concat_dns_servers(-1);
- set_env(ENV_DNS_SERVERS, p ? p : "");
- avahi_free(p);
-
- set_env(ENV_INTERFACE, name);
-
- snprintf(ia, sizeof(ia), "%i", (int) interface);
- snprintf(pa, sizeof(pa), "%i", (int) protocol);
-
- if (daemon_exec("/", &ret, AVAHI_DNSCONF_SCRIPT, AVAHI_DNSCONF_SCRIPT, new ? "+" : "-", address, ia, pa, avahi_proto_to_string(protocol), NULL) < 0)
- daemon_log(LOG_WARNING, "Failed to run script");
- else if (ret != 0)
- daemon_log(LOG_WARNING, "Script returned with non-zero exit code %i", ret);
-}
-
-static int new_line(const char *l) {
- assert(l);
-
- if (state == ACKWAIT) {
- if (*l != '+') {
- daemon_log(LOG_ERR, "Avahi command failed: %s", l);
- return -1;
- }
-
- daemon_log(LOG_INFO, "Successfully connected to Avahi daemon.");
- state = BROWSING;
- } else {
- AvahiIfIndex interface;
- AvahiProtocol protocol;
- int i_interface, i_protocol, port;
- char a[AVAHI_ADDRESS_STR_MAX];
-
- assert(state == BROWSING);
-
- if (*l != '<' && *l != '>') {
- daemon_log(LOG_ERR, "Avahi sent us an invalid browsing line: %s", l);
- return -1;
- }
-
- if (sscanf(l+1, "%i %i %39s %i", &i_interface, &i_protocol, a, &port) != 4) {
- daemon_log(LOG_ERR, "Failed to parse browsing line: %s", l);
- return -1;
- }
-
- interface = (AvahiIfIndex) i_interface;
- protocol = (AvahiProtocol) i_protocol;
-
- if (*l == '>') {
- if (port != 53)
- daemon_log(LOG_WARNING, "DNS server with port address != 53 found, ignoring");
- else {
- daemon_log(LOG_INFO, "New DNS Server %s (interface: %i.%s)", a, interface, avahi_proto_to_string(protocol));
- new_server_info(interface, protocol, a);
- run_script(1, interface, protocol, a);
- }
- } else {
- DNSServerInfo *i;
-
- if (port == 53)
- if ((i = get_server_info(interface, protocol, a))) {
- daemon_log(LOG_INFO, "DNS Server %s removed (interface: %i.%s)", a, interface, avahi_proto_to_string(protocol));
- server_info_free(i);
- run_script(0, interface, protocol, a);
- }
- }
-
- }
-
- return 0;
-}
-
-static int do_connect(void) {
- int fd = -1;
-
- if ((fd = open_socket()) < 0)
- goto fail;
-
- if (loop_write(fd, BROWSE_DNS_SERVERS, sizeof(BROWSE_DNS_SERVERS)-1) < 0) {
- daemon_log(LOG_ERR, "write(): %s", strerror(errno));
- goto fail;
- }
-
- state = ACKWAIT;
- return fd;
-
-fail:
- if (fd >= 0)
- close(fd);
-
- return -1;
-}
-
-static void free_dns_server_info_list(void) {
- while (servers) {
- AvahiIfIndex interface = servers->interface;
- AvahiProtocol protocol = servers->protocol;
- char *address = avahi_strdup(servers->address);
- server_info_free(servers);
-
- run_script(0, interface, protocol, address);
- avahi_free(address);
- }
-}
-
-static void help(FILE *f, const char *argv0) {
- fprintf(f,
- "%s [options]\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 DNS server data\n"
- " -c --check Return 0 if a daemon is already running\n"
- " -V --version Show version\n",
- argv0);
-}
-
-static int parse_command_line(int argc, char *argv[]) {
- int c;
-
- 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' },
- { "version", no_argument, NULL, 'V' },
- { "refresh", no_argument, NULL, 'r' },
- { "check", no_argument, NULL, 'c' },
- { NULL, 0, NULL, 0 }
- };
-
- while ((c = getopt_long(argc, argv, "hDkVrcs", long_options, NULL)) >= 0) {
-
- switch(c) {
- case 'h':
- command = DAEMON_HELP;
- break;
- case 'D':
- daemonize = 1;
- break;
- case 's':
- use_syslog = 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;
- default:
- return -1;
- }
- }
-
- if (optind < argc) {
- fprintf(stderr, "Too many arguments\n");
- return -1;
- }
-
- return 0;
-}
-
-static int run_daemon(void) {
- int fd = -1, ret = -1;
- char buf[1024];
- size_t buflen = 0;
-
- AVAHI_LLIST_HEAD_INIT(DNSServerInfo, servers);
-
- daemon_signal_init(SIGINT, SIGTERM, SIGCHLD, SIGHUP, 0);
-
- /* Allocate some memory for our environment variables */
- putenv(avahi_strdup(ENV_INTERFACE"="));
- putenv(avahi_strdup(ENV_DNS_SERVERS"="));
- putenv(avahi_strdup(ENV_INTERFACE_DNS_SERVERS"="));
-
- if ((fd = do_connect()) < 0)
- goto finish;
-
- if (daemonize)
- daemon_retval_send(0);
-
- ret = 0;
-
- while (!quit) {
- fd_set rfds, wfds;
-
- FD_ZERO(&rfds);
- FD_ZERO(&wfds);
-
- FD_SET(fd, &rfds);
- FD_SET(daemon_signal_fd(), &rfds);
-
- for (;;) {
- if (select(fd+1, &rfds, NULL, NULL, NULL) < 0) {
- if (errno == EINTR)
- continue;
-
- daemon_log(LOG_ERR, "select(): %s", strerror(errno));
- goto finish;
- }
-
- break;
- }
-
- if (FD_ISSET(daemon_signal_fd(), &rfds)) {
-
- int sig;
-
- if ((sig = daemon_signal_next()) <= 0) {
- daemon_log(LOG_ERR, "daemon_signal_next() failed");
- goto finish;
- }
-
- switch(sig) {
- case SIGINT:
- case SIGTERM:
- daemon_log(LOG_INFO, "Got %s, quitting.", sig == SIGINT ? "SIGINT" : "SIGTERM");
- ret = 0;
- goto finish;
-
- case SIGCHLD:
- waitpid(-1, NULL, WNOHANG);
- break;
-
- case SIGHUP:
- daemon_log(LOG_INFO, "Refreshing DNS Server list");
-
- close(fd);
- free_dns_server_info_list();
-
- if ((fd = do_connect()) < 0)
- goto finish;
-
- break;
- }
-
- } else if (FD_ISSET(fd, &rfds)) {
- ssize_t r;
- char *n;
-
- if ((r = read(fd, buf, sizeof(buf) - buflen - 1)) <= 0) {
- daemon_log(LOG_ERR, "read(): %s", r < 0 ? strerror(errno) : "EOF");
- goto finish;
- }
-
- buflen += r;
- assert(buflen <= sizeof(buf)-1);
-
- while ((n = memchr(buf, '\n', buflen))) {
- *(n++) = 0;
-
- if (new_line(buf) < 0)
- goto finish;
-
- buflen -= (n - buf);
- memmove(buf, n, buflen);
- }
-
- if (buflen >= sizeof(buf)-1) {
- /* The incoming line is horribly long */
- buf[sizeof(buf)-1] = 0;
-
- if (new_line(buf) < 0)
- goto finish;
-
- buflen = 0;
- }
- }
- }
-
-finish:
-
- free_dns_server_info_list();
-
- if (fd >= 0)
- close(fd);
-
- daemon_signal_done();
-
- if (ret != 0 && daemonize)
- daemon_retval_send(1);
-
- return ret;
-}
-
-static const char* pid_file_proc(void) {
- return AVAHI_RUNTIME_DIR"/avahi-dnsconfd.pid";
-}
-
-int main(int argc, char *argv[]) {
- char *argv0;
- int r = 1;
- int wrote_pid_file = 0;
-
- if ((argv0 = strrchr(argv[0], '/')))
- argv0++;
- else
- argv0 = argv[0];
-
- daemon_pid_file_ident = daemon_log_ident = argv0;
- daemon_pid_file_proc = pid_file_proc;
-
- if (parse_command_line(argc, argv) < 0)
- goto finish;
-
- if (command == DAEMON_RUN) {
- pid_t pid;
-
- 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 (run_daemon() < 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();
-
- if (wrote_pid_file)
- daemon_pid_file_remove();
-
- return r;
-}
projects / catta / blobdiff