--- /dev/null
+/*
+ * $Id$
+ *
+ * Authors:
+ * Pedro Roque <roque@di.fc.ul.pt>
+ * Lars Fenneberg <lf@elemental.net>
+ *
+ * This software is Copyright 1996-2000 by the above mentioned author(s),
+ * All Rights Reserved.
+ *
+ * The license which is distributed with this software in the file COPYRIGHT
+ * applies to this software. If your distribution is missing this file, you
+ * may request it from <pekkas@netcore.fi>.
+ *
+ */
+
+#include <config.h>
+#include <includes.h>
+#include <radvd.h>
+#include <pathnames.h>
+
+struct Interface *IfaceList = NULL;
+
+char usage_str[] =
+ "[-vh] [-d level] [-C config_file] [-m log_method] [-l log_file]\n"
+ "\t[-f facility] [-p pid_file] [-u username] [-t chrootdir]";
+
+#ifdef HAVE_GETOPT_LONG
+struct option prog_opt[] = {
+ {"debug", 1, 0, 'd'},
+ {"config", 1, 0, 'C'},
+ {"pidfile", 1, 0, 'p'},
+ {"logfile", 1, 0, 'l'},
+ {"logmethod", 1, 0, 'm'},
+ {"facility", 1, 0, 'f'},
+ {"username", 1, 0, 'u'},
+ {"chrootdir", 1, 0, 't'},
+ {"version", 0, 0, 'v'},
+ {"help", 0, 0, 'h'},
+ {NULL, 0, 0, 0}
+};
+#endif
+
+extern FILE *yyin;
+
+char *conf_file = NULL;
+char *pname;
+int sock = -1;
+
+volatile int sighup_received = 0;
+volatile int sigterm_received = 0;
+volatile int sigint_received = 0;
+
+void sighup_handler(int sig);
+void sigterm_handler(int sig);
+void sigint_handler(int sig);
+void timer_handler(void *data);
+void config_interface(void);
+void kickoff_adverts(void);
+void stop_adverts(void);
+void version(void);
+void usage(void);
+int drop_root_privileges(const char *);
+int readin_config(char *);
+int check_conffile_perm(const char *, const char *);
+
+int
+main(int argc, char *argv[])
+{
+ unsigned char msg[MSG_SIZE];
+ char pidstr[16];
+ int c, log_method;
+ char *logfile, *pidfile;
+ sigset_t oset, nset;
+ int facility, fd;
+ char *username = NULL;
+ char *chrootdir = NULL;
+#ifdef HAVE_GETOPT_LONG
+ int opt_idx;
+#endif
+
+ pname = ((pname=strrchr(argv[0],'/')) != NULL)?pname+1:argv[0];
+
+ srand((unsigned int)time(NULL));
+
+ log_method = L_STDERR_SYSLOG;
+ logfile = PATH_RADVD_LOG;
+ conf_file = PATH_RADVD_CONF;
+ facility = LOG_FACILITY;
+ pidfile = PATH_RADVD_PID;
+
+ /* parse args */
+#ifdef HAVE_GETOPT_LONG
+ while ((c = getopt_long(argc, argv, "d:C:l:m:p:t:u:vh", prog_opt, &opt_idx)) > 0)
+#else
+ while ((c = getopt(argc, argv, "d:C:l:m:p:t:u:vh")) > 0)
+#endif
+ {
+ switch (c) {
+ case 'C':
+ conf_file = optarg;
+ break;
+ case 'd':
+ set_debuglevel(atoi(optarg));
+ break;
+ case 'f':
+ facility = atoi(optarg);
+ break;
+ case 'l':
+ logfile = optarg;
+ break;
+ case 'p':
+ pidfile = optarg;
+ break;
+ case 'm':
+ if (!strcmp(optarg, "syslog"))
+ {
+ log_method = L_SYSLOG;
+ }
+ else if (!strcmp(optarg, "stderr_syslog"))
+ {
+ log_method = L_STDERR_SYSLOG;
+ }
+ else if (!strcmp(optarg, "stderr"))
+ {
+ log_method = L_STDERR;
+ }
+ else if (!strcmp(optarg, "logfile"))
+ {
+ log_method = L_LOGFILE;
+ }
+ else if (!strcmp(optarg, "none"))
+ {
+ log_method = L_NONE;
+ }
+ else
+ {
+ fprintf(stderr, "%s: unknown log method: %s\n", pname, optarg);
+ exit(1);
+ }
+ break;
+ case 't':
+ chrootdir = strdup(optarg);
+ break;
+ case 'u':
+ username = strdup(optarg);
+ break;
+ case 'v':
+ version();
+ break;
+ case 'h':
+ usage();
+#ifdef HAVE_GETOPT_LONG
+ case ':':
+ fprintf(stderr, "%s: option %s: parameter expected\n", pname,
+ prog_opt[opt_idx].name);
+ exit(1);
+#endif
+ case '?':
+ exit(1);
+ }
+ }
+
+ if (chrootdir) {
+ if (!username) {
+ fprintf(stderr, "Chroot as root is not safe, exiting\n");
+ exit(1);
+ }
+
+ if (chroot(chrootdir) == -1) {
+ perror("chroot");
+ exit (1);
+ }
+
+ if (chdir("/") == -1) {
+ perror("chdir");
+ exit (1);
+ }
+ /* username will be switched later */
+ }
+
+ if (log_open(log_method, pname, logfile, facility) < 0)
+ exit(1);
+
+ flog(LOG_INFO, "version %s started", VERSION);
+
+ /* get a raw socket for sending and receiving ICMPv6 messages */
+ sock = open_icmpv6_socket();
+ if (sock < 0)
+ exit(1);
+
+ /* drop root privileges if requested. */
+ if (username) {
+ if (drop_root_privileges(username) < 0)
+ exit(1);
+ }
+
+ /* check that 'other' cannot write the file
+ * for non-root, also that self/own group can't either
+ */
+ if (check_conffile_perm(username, conf_file) < 0) {
+ if (get_debuglevel() == 0)
+ exit(1);
+ else
+ flog(LOG_WARNING, "Insecure file permissions, but continuing anyway");
+ }
+
+ /* if we know how to do it, check whether forwarding is enabled */
+ if (check_ip6_forwarding()) {
+ if (get_debuglevel() == 0) {
+ flog(LOG_ERR, "IPv6 forwarding seems to be disabled, exiting");
+ exit(1);
+ }
+ else
+ flog(LOG_WARNING, "IPv6 forwarding seems to be disabled, but continuing anyway.");
+ }
+
+ /* parse config file */
+ if (readin_config(conf_file) < 0)
+ exit(1);
+
+ /* FIXME: not atomic if pidfile is on an NFS mounted volume */
+ if ((fd = open(pidfile, O_CREAT|O_EXCL|O_WRONLY, 0644)) < 0)
+ {
+ flog(LOG_ERR, "another radvd seems to be already running, terminating");
+ exit(1);
+ }
+
+ /*
+ * okay, config file is read in, socket and stuff is setup, so
+ * lets fork now...
+ */
+
+ if (get_debuglevel() == 0) {
+
+ /* Detach from controlling terminal */
+ if (daemon(0, 0) < 0)
+ perror("daemon");
+
+ /* close old logfiles, including stderr */
+ log_close();
+
+ /* reopen logfiles, but don't log to stderr unless explicitly requested */
+ if (log_method == L_STDERR_SYSLOG)
+ log_method = L_SYSLOG;
+ if (log_open(log_method, pname, logfile, facility) < 0)
+ exit(1);
+
+ }
+
+ /*
+ * config signal handlers, also make sure ALRM isn't blocked and raise a warning if so
+ * (some stupid scripts/pppd appears to do this...)
+ */
+ sigemptyset(&nset);
+ sigaddset(&nset, SIGALRM);
+ sigprocmask(SIG_UNBLOCK, &nset, &oset);
+ if (sigismember(&oset, SIGALRM))
+ flog(LOG_WARNING, "SIGALRM has been unblocked. Your startup environment might be wrong.");
+
+ signal(SIGHUP, sighup_handler);
+ signal(SIGTERM, sigterm_handler);
+ signal(SIGINT, sigint_handler);
+
+ snprintf(pidstr, sizeof(pidstr), "%d\n", getpid());
+
+ write(fd, pidstr, strlen(pidstr));
+
+ close(fd);
+
+ config_interface();
+ kickoff_adverts();
+
+ /* enter loop */
+
+ for (;;)
+ {
+ int len, hoplimit;
+ struct sockaddr_in6 rcv_addr;
+ struct in6_pktinfo *pkt_info = NULL;
+
+ len = recv_rs_ra(sock, msg, &rcv_addr, &pkt_info, &hoplimit);
+ if (len > 0)
+ process(sock, IfaceList, msg, len,
+ &rcv_addr, pkt_info, hoplimit);
+
+ if (sigterm_received || sigint_received) {
+ stop_adverts();
+ break;
+ }
+
+ if (sighup_received)
+ {
+ reload_config();
+ sighup_received = 0;
+ }
+ }
+
+ unlink(pidfile);
+ exit(0);
+}
+
+void
+timer_handler(void *data)
+{
+ struct Interface *iface = (struct Interface *) data;
+ double next;
+
+ dlog(LOG_DEBUG, 4, "timer_handler called for %s", iface->Name);
+
+ send_ra(sock, iface, NULL);
+
+ next = rand_between(iface->MinRtrAdvInterval, iface->MaxRtrAdvInterval);
+
+ if (iface->init_racount < MAX_INITIAL_RTR_ADVERTISEMENTS)
+ {
+ iface->init_racount++;
+ next = min(MAX_INITIAL_RTR_ADVERT_INTERVAL, next);
+ }
+
+ set_timer(&iface->tm, next);
+}
+
+void
+config_interface(void)
+{
+ struct Interface *iface;
+ for(iface=IfaceList; iface; iface=iface->next)
+ {
+ if (iface->AdvLinkMTU)
+ set_interface_linkmtu(iface->Name, iface->AdvLinkMTU);
+ if (iface->AdvCurHopLimit)
+ set_interface_curhlim(iface->Name, iface->AdvCurHopLimit);
+ if (iface->AdvReachableTime)
+ set_interface_reachtime(iface->Name, iface->AdvReachableTime);
+ if (iface->AdvRetransTimer)
+ set_interface_retranstimer(iface->Name, iface->AdvRetransTimer);
+ }
+}
+
+void
+kickoff_adverts(void)
+{
+ struct Interface *iface;
+
+ /*
+ * send initial advertisement and set timers
+ */
+
+ for(iface=IfaceList; iface; iface=iface->next)
+ {
+ if( ! iface->UnicastOnly )
+ {
+ init_timer(&iface->tm, timer_handler, (void *) iface);
+ if (iface->AdvSendAdvert)
+ {
+ /* send an initial advertisement */
+ send_ra(sock, iface, NULL);
+
+ iface->init_racount++;
+
+ set_timer(&iface->tm,
+ min(MAX_INITIAL_RTR_ADVERT_INTERVAL,
+ iface->MaxRtrAdvInterval));
+ }
+ }
+ }
+}
+
+void
+stop_adverts(void)
+{
+ struct Interface *iface;
+
+ /*
+ * send final RA (a SHOULD in RFC2461 section 6.2.5)
+ */
+
+ for (iface=IfaceList; iface; iface=iface->next) {
+ if( ! iface->UnicastOnly ) {
+ if (iface->AdvSendAdvert) {
+ /* send a final advertisement with zero Router Lifetime */
+ iface->AdvDefaultLifetime = 0;
+ send_ra(sock, iface, NULL);
+ }
+ }
+ }
+}
+
+void reload_config(void)
+{
+ struct Interface *iface;
+
+ flog(LOG_INFO, "attempting to reread config file");
+
+ dlog(LOG_DEBUG, 4, "reopening log");
+ if (log_reopen() < 0)
+ exit(1);
+
+ /* disable timers, free interface and prefix structures */
+ for(iface=IfaceList; iface; iface=iface->next)
+ {
+ /* check that iface->tm was set in the first place */
+ if (iface->tm.next && iface->tm.prev)
+ {
+ dlog(LOG_DEBUG, 4, "disabling timer for %s", iface->Name);
+ clear_timer(&iface->tm);
+ }
+ }
+
+ iface=IfaceList;
+ while(iface)
+ {
+ struct Interface *next_iface = iface->next;
+ struct AdvPrefix *prefix;
+ struct AdvRoute *route;
+ struct AdvRDNSS *rdnss;
+
+ dlog(LOG_DEBUG, 4, "freeing interface %s", iface->Name);
+
+ prefix = iface->AdvPrefixList;
+ while (prefix)
+ {
+ struct AdvPrefix *next_prefix = prefix->next;
+
+ free(prefix);
+ prefix = next_prefix;
+ }
+
+ route = iface->AdvRouteList;
+ while (route)
+ {
+ struct AdvRoute *next_route = route->next;
+
+ free(route);
+ route = next_route;
+ }
+
+ rdnss = iface->AdvRDNSSList;
+ while (rdnss)
+ {
+ struct AdvRDNSS *next_rdnss = rdnss->next;
+
+ free(rdnss);
+ rdnss = next_rdnss;
+ }
+
+ free(iface);
+ iface = next_iface;
+ }
+
+ IfaceList = NULL;
+
+ /* reread config file */
+ if (readin_config(conf_file) < 0)
+ exit(1);
+
+ config_interface();
+ kickoff_adverts();
+
+ flog(LOG_INFO, "resuming normal operation");
+}
+
+void
+sighup_handler(int sig)
+{
+ /* Linux has "one-shot" signals, reinstall the signal handler */
+ signal(SIGHUP, sighup_handler);
+
+ dlog(LOG_DEBUG, 4, "sighup_handler called");
+
+ sighup_received = 1;
+}
+
+void
+sigterm_handler(int sig)
+{
+ /* Linux has "one-shot" signals, reinstall the signal handler */
+ signal(SIGTERM, sigterm_handler);
+
+ dlog(LOG_DEBUG, 4, "sigterm_handler called");
+
+ sigterm_received = 1;
+}
+
+void
+sigint_handler(int sig)
+{
+ /* Linux has "one-shot" signals, reinstall the signal handler */
+ signal(SIGINT, sigint_handler);
+
+ dlog(LOG_DEBUG, 4, "sigint_handler called");
+
+ sigint_received = 1;
+}
+
+int
+drop_root_privileges(const char *username)
+{
+ struct passwd *pw = NULL;
+ pw = getpwnam(username);
+ if (pw) {
+ if (initgroups(username, pw->pw_gid) != 0 || setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
+ flog(LOG_ERR, "Couldn't change to '%.32s' uid=%d gid=%d\n",
+ username, pw->pw_uid, pw->pw_gid);
+ return (-1);
+ }
+ }
+ else {
+ flog(LOG_ERR, "Couldn't find user '%.32s'\n", username);
+ return (-1);
+ }
+ return 0;
+}
+
+int
+check_conffile_perm(const char *username, const char *conf_file)
+{
+ struct stat *st = NULL;
+ struct passwd *pw = NULL;
+ FILE *fp = fopen(conf_file, "r");
+
+ if (fp == NULL) {
+ flog(LOG_ERR, "can't open %s: %s", conf_file, strerror(errno));
+ return (-1);
+ }
+ fclose(fp);
+
+ st = malloc(sizeof(struct stat));
+ if (st == NULL)
+ goto errorout;
+
+ if (!username)
+ username = "root";
+
+ pw = getpwnam(username);
+
+ if (stat(conf_file, st) || pw == NULL)
+ goto errorout;
+
+ if (st->st_mode & S_IWOTH) {
+ flog(LOG_ERR, "Insecure file permissions (writable by others): %s", conf_file);
+ goto errorout;
+ }
+
+ /* for non-root: must not be writable by self/own group */
+ if (strncmp(username, "root", 5) != 0 &&
+ ((st->st_mode & S_IWGRP && pw->pw_gid == st->st_gid) ||
+ (st->st_mode & S_IWUSR && pw->pw_uid == st->st_uid))) {
+ flog(LOG_ERR, "Insecure file permissions (writable by self/group): %s", conf_file);
+ goto errorout;
+ }
+
+ free(st);
+ return 0;
+
+errorout:
+ if (st)
+ free(st);
+ return(-1);
+}
+
+int
+check_ip6_forwarding(void)
+{
+ int forw_sysctl[] = { SYSCTL_IP6_FORWARDING };
+ int value;
+ size_t size = sizeof(value);
+ FILE *fp = NULL;
+
+#ifdef __linux__
+ fp = fopen(PROC_SYS_IP6_FORWARDING, "r");
+ if (fp) {
+ fscanf(fp, "%d", &value);
+ fclose(fp);
+ }
+ else
+ flog(LOG_DEBUG, "Correct IPv6 forwarding procfs entry not found, "
+ "perhaps the procfs is disabled, "
+ "or the kernel interface has changed?");
+#endif /* __linux__ */
+
+ if (!fp && sysctl(forw_sysctl, sizeof(forw_sysctl)/sizeof(forw_sysctl[0]),
+ &value, &size, NULL, 0) < 0) {
+ flog(LOG_DEBUG, "Correct IPv6 forwarding sysctl branch not found, "
+ "perhaps the kernel interface has changed?");
+ return(0); /* this is of advisory value only */
+ }
+
+ if (value != 1) {
+ flog(LOG_DEBUG, "IPv6 forwarding setting is: %u, should be 1", value);
+ return(-1);
+ }
+
+ return(0);
+}
+
+int
+readin_config(char *fname)
+{
+ if ((yyin = fopen(fname, "r")) == NULL)
+ {
+ flog(LOG_ERR, "can't open %s: %s", fname, strerror(errno));
+ return (-1);
+ }
+
+ if (yyparse() != 0)
+ {
+ flog(LOG_ERR, "error parsing or activating the config file: %s", fname);
+ return (-1);
+ }
+
+ fclose(yyin);
+ return 0;
+}
+
+void
+version(void)
+{
+ fprintf(stderr, "Version: %s\n\n", VERSION);
+ fprintf(stderr, "Compiled in settings:\n");
+ fprintf(stderr, " default config file \"%s\"\n", PATH_RADVD_CONF);
+ fprintf(stderr, " default pidfile \"%s\"\n", PATH_RADVD_PID);
+ fprintf(stderr, " default logfile \"%s\"\n", PATH_RADVD_LOG);
+ fprintf(stderr, " default syslog facililty %d\n", LOG_FACILITY);
+ fprintf(stderr, "Please send bug reports or suggestions to %s.\n",
+ CONTACT_EMAIL);
+
+ exit(1);
+}
+
+void
+usage(void)
+{
+ fprintf(stderr, "usage: %s %s\n", pname, usage_str);
+ exit(1);
+}
+
projects / tinyos-2.x.git / blobdiff