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radvd.c
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radvd.c
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/*
*
* Authors:
* Pedro Roque <[email protected]>
* Lars Fenneberg <[email protected]>
*
* 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 <[email protected]>.
*
*/
#include "radvd.h"
#include "config.h"
#include "includes.h"
#include "pathnames.h"
#ifdef HAVE_NETLINK
#include "netlink.h"
#endif
#include "trigger.h"
#include <libgen.h>
#include <poll.h>
#include <sys/file.h>
#ifdef HAVE_GETOPT_LONG
/* clang-format off */
static char usage_str[] = {
"\n"
" -C, --config=PATH Set the config file. Default is /etc/radvd.d.\n"
" -c, --configtest Parse the config file and exit.\n"
" -d, --debug=NUM Set the debug level. Values can be 1, 2, 3, 4 or 5.\n"
" -f, --facility=NUM Set the logging facility.\n"
" -h, --help Show this help screen.\n"
" -l, --logfile=PATH Set the log file.\n"
" -m, --logmethod=X Set method to: syslog, stderr, stderr_syslog, logfile,\n"
" stderr_clean, or none.\n"
" -n, --nodaemon Prevent the daemonizing.\n"
" -p, --pidfile=PATH Set the pid file.\n"
" -t, --chrootdir=PATH Chroot to the specified path.\n"
" -u, --username=USER Switch to the specified user.\n"
" -T, --trigger_path=PATH Path to a pipe for use with a (PVDID) monitoring daemon.\n"
" -v, --version Print the version and quit.\n"
};
static struct option prog_opt[] = {
{"chrootdir", 1, 0, 't'},
{"config", 1, 0, 'C'},
{"configtest", 0, 0, 'c'},
{"debug", 1, 0, 'd'},
{"facility", 1, 0, 'f'},
{"help", 0, 0, 'h'},
{"logfile", 1, 0, 'l'},
{"logmethod", 1, 0, 'm'},
{"nodaemon", 0, 0, 'n'},
{"pidfile", 1, 0, 'p'},
{"username", 1, 0, 'u'},
{"trigger_path", 1, 0, 'p'},
{"version", 0, 0, 'v'},
{NULL, 0, 0, 0}
};
#else
static char usage_str[] = {
"[-hsvcn] [-d level] [-C config_path] [-m log_method] [-l log_file]\n"
"\t[-f facility] [-p pid_file] [-u username] [-t chrootdir] [-T trigger_pipe_path]"
};
/* clang-format on */
#endif
static volatile int sighup_received = 0;
static volatile int sigint_received = 0;
static volatile int sigterm_received = 0;
static volatile int sigusr1_received = 0;
static int check_conffile_perm(const char *, const char *);
static int drop_root_privileges(const char *);
static int open_and_lock_pid_file(char const *daemon_pid_file_ident);
static int write_pid_file(char const *daemon_pid_file_ident, pid_t pid);
static pid_t daemonp(int nochdir, int noclose, char const *daemon_pid_file_ident);
static pid_t do_daemonize(int log_method, char const *daemon_pid_file_ident);
static struct Interface *main_loop(int sock, struct Interface *ifaces, char const *conf_path, char *trigger_pipe_path);
static struct Interface *reload_config(int sock, struct Interface *ifaces, char const *conf_path);
static void check_pid_file(char const *daemon_pid_file_ident);
static void config_interface(struct Interface *iface);
static void kickoff_adverts(int sock, struct Interface *iface);
static void reset_prefix_lifetimes(struct Interface *ifaces);
static void reset_prefix_lifetimes_foo(struct Interface *iface, void *data);
static void setup_iface_foo(struct Interface *iface, void *data);
static void setup_ifaces(int sock, struct Interface *ifaces);
static void sighup_handler(int sig);
static void sigint_handler(int sig);
static void sigterm_handler(int sig);
static void sigusr1_handler(int sig);
static void stop_advert_foo(struct Interface *iface, void *data);
static void stop_adverts(int sock, struct Interface *ifaces);
static void timer_handler(int sock, struct Interface *iface);
static void usage(char const *pname);
static void version(void);
/* daemonize and write pid file. The pid of the daemon child process
* will be written to the pid file from the *parent* process. This
* insures there is no race condition as described in redhat bug 664783. */
static pid_t daemonp(int nochdir, int noclose, char const *daemon_pid_file_ident)
{
int pipe_ends[2];
if (0 != pipe(pipe_ends)) {
flog(LOG_ERR, "unable to create pipe: %s", strerror(errno));
exit(-1);
}
pid_t pid = fork();
if (-1 == pid) {
flog(LOG_ERR, "unable to fork in daemonp");
exit(-1);
} else if (0 == pid) {
/* Child process, detached.. */
pid = getpid();
close(pipe_ends[0]);
if (0 != write_pid_file(daemon_pid_file_ident, pid)) {
flog(LOG_ERR, "failure writing pid file");
exit(-1);
}
if (sizeof(pid) != write(pipe_ends[1], &pid, sizeof(pid))) {
flog(LOG_ERR, "failure piping pid to parent process");
}
umask(0);
if (-1 == setsid()) {
flog(LOG_ERR, "unable to become a session leader: %s", strerror(errno));
exit(-1);
}
if (nochdir == 0) {
if (chdir("/") == -1) {
perror("chdir");
exit(1);
}
}
if (noclose == 0) {
close(STDIN_FILENO);
close(STDOUT_FILENO);
close(STDERR_FILENO);
if (open("/dev/null", O_RDONLY) == -1) {
flog(LOG_ERR, "unable to redirect stdin to /dev/null");
exit(-1);
}
if (open("/dev/null", O_WRONLY) == -1) {
flog(LOG_ERR, "unable to redirect stdout to /dev/null");
exit(-1);
}
if (open("/dev/null", O_RDWR) == -1) {
flog(LOG_ERR, "unable to redirect stderr to /dev/null");
exit(-1);
}
}
} else {
/* Parent. Make sure the pid file is written before exiting. */
close(pipe_ends[1]);
pid_t msg = -1;
ssize_t rc = read(pipe_ends[0], &msg, sizeof(msg));
if (rc != sizeof(msg)) {
flog(LOG_ERR, "child failed to signal pid file written: %s", strerror(errno));
exit(-1);
} else if (msg != pid) {
flog(LOG_ERR, "child wrote wrong pid to pid file: %d", msg);
exit(-1);
} else {
dlog(LOG_DEBUG, 5, "child signaled pid file written: %d", msg);
}
close(pipe_ends[0]);
return pid;
}
return 0;
}
int main(int argc, char *argv[])
{
int c;
int log_method = L_STDERR_SYSLOG;
char *logfile = PATH_RADVD_LOG;
int facility = LOG_FACILITY;
char *username = NULL;
char *chrootdir = NULL;
char *trigger_pipe_path = NULL;
int configtest = 0;
int daemonize = 1;
char const *pname = ((pname = strrchr(argv[0], '/')) != NULL) ? pname + 1 : argv[0];
srand((unsigned int)time(NULL));
char const *conf_path = PATH_RADVD_CONF;
char const *daemon_pid_file_ident = PATH_RADVD_PID;
/* parse args */
#define OPTIONS_STR "d:C:l:m:p:t:u:T:vhcn"
#ifdef HAVE_GETOPT_LONG
int opt_idx;
while ((c = getopt_long(argc, argv, OPTIONS_STR, prog_opt, &opt_idx)) > 0)
#else
while ((c = getopt(argc, argv, OPTIONS_STR)) > 0)
#endif
{
switch (c) {
case 'C':
conf_path = optarg;
break;
case 'd':
set_debuglevel(atoi(optarg));
break;
case 'f':
facility = atoi(optarg);
break;
case 'l':
logfile = optarg;
break;
case 'p':
daemon_pid_file_ident = 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, "stderr_clean")) {
log_method = L_STDERR_CLEAN;
} 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 'T':
trigger_pipe_path = strdup(optarg);
break;
case 'v':
version();
break;
case 'c':
configtest = 1;
break;
case 'n':
daemonize = 0;
break;
case 'h':
usage(pname);
#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);
}
}
/* TODO: Seems like this chroot'ing should happen *after* daemonizing for
* the sake of the PID file. */
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 (configtest) {
set_debuglevel(1);
switch (log_method) {
case L_STDERR:
case L_STDERR_CLEAN:
break;
case L_STDERR_SYSLOG:
case L_NONE:
case L_SYSLOG:
case L_LOGFILE:
default:
log_method = L_STDERR;
break;
}
}
if (log_open(log_method, pname, logfile, facility) < 0) {
perror("log_open");
exit(1);
}
if (!configtest) {
flog(LOG_INFO, "version %s started", VERSION);
}
/* check that 'other' cannot write the file
* for non-root, also that self/own group can't either
*/
if (check_conffile_perm(username, conf_path) != 0) {
if (get_debuglevel() == 0) {
flog(LOG_ERR, "exiting, permissions on conf_file invalid");
exit(1);
} else
flog(LOG_WARNING, "Insecure file permissions, but continuing anyway");
}
/* parse config file */
struct Interface *ifaces = NULL;
if ((ifaces = readin_config(conf_path)) == 0) {
flog(LOG_ERR, "exiting, failed to read config file");
exit(1);
}
if (configtest) {
free_ifaces(ifaces);
exit(0);
}
/* get a raw socket for sending and receiving ICMPv6 messages */
int sock = open_icmpv6_socket();
if (sock < 0) {
perror("open_icmpv6_socket");
exit(1);
}
/* if we know how to do it, check whether forwarding is enabled */
if (check_ip6_forwarding()) {
flog(LOG_WARNING, "IPv6 forwarding seems to be disabled, but continuing anyway");
}
int const pidfd = open_and_lock_pid_file(daemon_pid_file_ident);
/*
* okay, config file is read in, socket and stuff is setup, so
* lets fork now...
*/
if (daemonize) {
pid_t pid = do_daemonize(log_method, daemon_pid_file_ident);
if (pid != 0 && pid != -1) {
/* We want to see clean output from valgrind, so free username, chrootdir,
* and ifaces in the child process. */
if (ifaces)
free_ifaces(ifaces);
if (username)
free(username);
if (chrootdir)
free(chrootdir);
exit(0);
}
} else {
if (0 != write_pid_file(daemon_pid_file_ident, getpid())) {
flog(LOG_ERR, "failure writing pid file detected");
exit(-1);
}
}
check_pid_file(daemon_pid_file_ident);
#ifdef __linux__
/* for privsep */ {
dlog(LOG_DEBUG, 3, "initializing privsep");
int pipefds[2];
if (pipe(pipefds) != 0) {
flog(LOG_ERR, "Couldn't create privsep pipe.");
return -1;
}
pid_t pid = fork();
if (pid == -1) {
flog(LOG_ERR, "Couldn't fork for privsep.");
return -1;
}
if (pid == 0) {
/* We want to see clean output from valgrind, so free username, chrootdir,
* and ifaces in the child process. */
if (ifaces)
free_ifaces(ifaces);
if (username)
free(username);
if (chrootdir)
free(chrootdir);
close(pipefds[1]);
privsep_init(pipefds[0]);
_exit(0);
}
dlog(LOG_DEBUG, 3, "radvd privsep PID is %d", pid);
/* Continue execution (will drop privileges soon) */
close(pipefds[0]);
privsep_set_write_fd(pipefds[1]);
}
#endif
if (username) {
if (drop_root_privileges(username) < 0) {
perror("drop_root_privileges");
flog(LOG_ERR, "unable to drop root privileges");
exit(1);
}
dlog(LOG_DEBUG, 3, "running as user: %s", username);
}
setup_ifaces(sock, ifaces);
ifaces = main_loop(sock, ifaces, conf_path, trigger_pipe_path);
stop_adverts(sock, ifaces);
flog(LOG_INFO, "removing %s", daemon_pid_file_ident);
unlink(daemon_pid_file_ident);
close(pidfd);
if (ifaces)
free_ifaces(ifaces);
if (chrootdir)
free(chrootdir);
if (username)
free(username);
flog(LOG_INFO, "returning from radvd main");
log_close();
return 0;
}
static struct Interface *main_loop(
int sock,
struct Interface *ifaces,
char const *conf_path,
char *trigger_pipe_path)
{
struct pollfd fds[3];
sigset_t sigmask;
sigset_t sigempty;
struct sigaction sa;
sigemptyset(&sigempty);
sigemptyset(&sigmask);
sigaddset(&sigmask, SIGHUP);
sigaddset(&sigmask, SIGTERM);
sigaddset(&sigmask, SIGINT);
sigaddset(&sigmask, SIGUSR1);
sigprocmask(SIG_BLOCK, &sigmask, NULL);
sa.sa_handler = sighup_handler;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sigaction(SIGHUP, &sa, 0);
sa.sa_handler = sigterm_handler;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sigaction(SIGTERM, &sa, 0);
sa.sa_handler = sigint_handler;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sigaction(SIGINT, &sa, 0);
sa.sa_handler = sigusr1_handler;
sigemptyset(&sa.sa_mask);
sa.sa_flags = 0;
sigaction(SIGUSR1, &sa, 0);
memset(fds, 0, sizeof(fds));
fds[0].fd = sock;
fds[0].events = POLLIN;
#if HAVE_NETLINK
fds[1].fd = netlink_socket();
fds[1].events = POLLIN;
#else
fds[1].fd = -1;
#endif
if (trigger_pipe_path != NULL) {
fds[2].fd = trigger_pipe(trigger_pipe_path);
fds[2].events = POLLIN;
}
else {
fds[2].fd = -1;
}
for (;;) {
struct timespec *tsp = 0;
struct Interface *next_iface_to_expire = find_iface_by_time(ifaces);
if (next_iface_to_expire) {
static struct timespec ts;
int timeout = next_time_msec(next_iface_to_expire);
ts.tv_sec = timeout / 1000;
ts.tv_nsec = (timeout - 1000 * ts.tv_sec) * 1000000;
tsp = &ts;
dlog(LOG_DEBUG, 1, "polling for %g second(s), next iface is %s", timeout / 1000.0,
next_iface_to_expire->props.name);
} else {
dlog(LOG_DEBUG, 1, "no iface is next. Polling indefinitely");
}
#ifdef HAVE_PPOLL
int rc = ppoll(fds, sizeof(fds) / sizeof(fds[0]), tsp, &sigempty);
#else
int rc = poll(fds, sizeof(fds) / sizeof(fds[0]), 1000 * tsp->tv_sec);
#endif
if (rc > 0) {
#ifdef HAVE_NETLINK
if (fds[1].revents & (POLLERR | POLLHUP | POLLNVAL)) {
flog(LOG_WARNING, "socket error on fds[1].fd");
} else if (fds[1].revents & POLLIN) {
process_netlink_msg(fds[1].fd, ifaces);
}
#endif
if (fds[2].revents & (POLLERR | POLLHUP | POLLNVAL)) {
flog(LOG_WARNING, "pipe error on fds[2].fd");
} else if (fds[2].revents & POLLIN) {
process_trigger_msg(fds[2].fd);
}
if (fds[0].revents & (POLLERR | POLLHUP | POLLNVAL)) {
flog(LOG_WARNING, "socket error on fds[0].fd");
} else if (fds[0].revents & POLLIN) {
int len, hoplimit;
struct sockaddr_in6 rcv_addr;
struct in6_pktinfo *pkt_info = NULL;
unsigned char msg[MSG_SIZE_RECV];
unsigned char chdr[CMSG_SPACE(sizeof(struct in6_pktinfo)) + CMSG_SPACE(sizeof(int))];
len = recv_rs_ra(sock, msg, &rcv_addr, &pkt_info, &hoplimit, chdr);
if (len > 0 && pkt_info) {
process(sock, ifaces, msg, len, &rcv_addr, pkt_info, hoplimit);
} else if (!pkt_info) {
dlog(LOG_INFO, 4, "recv_rs_ra returned null pkt_info");
} else if (len <= 0) {
dlog(LOG_INFO, 4, "recv_rs_ra returned len <= 0: %d", len);
}
}
} else if (rc == 0) {
if (next_iface_to_expire)
timer_handler(sock, next_iface_to_expire);
} else if (rc == -1) {
dlog(LOG_INFO, 3, "poll returned early: %s", strerror(errno));
}
if (sigint_received) {
flog(LOG_WARNING, "exiting, %d sigint(s) received", sigint_received);
break;
}
if (sigterm_received) {
flog(LOG_WARNING, "exiting, %d sigterm(s) received", sigterm_received);
break;
}
if (sighup_received) {
dlog(LOG_INFO, 3, "sig hup received");
ifaces = reload_config(sock, ifaces, conf_path);
sighup_received = 0;
}
if (sigusr1_received) {
dlog(LOG_INFO, 3, "sig usr1 received");
reset_prefix_lifetimes(ifaces);
sigusr1_received = 0;
}
}
return ifaces;
}
static pid_t do_daemonize(int log_method, char const *daemon_pid_file_ident)
{
pid_t pid = -1;
if (L_STDERR_SYSLOG == log_method || L_STDERR == log_method) {
pid = daemonp(1, 1, daemon_pid_file_ident);
} else {
pid = daemonp(0, 0, daemon_pid_file_ident);
}
if (-1 == pid) {
flog(LOG_ERR, "unable to daemonize: %s", strerror(errno));
exit(-1);
}
return pid;
}
static int open_pid_file(char const *daemon_pid_file_ident)
{
int pidfd = open(daemon_pid_file_ident, O_SYNC | O_CREAT | O_RDWR, 0644);
if (-1 == pidfd) {
flog(LOG_ERR, "unable to open pid file, %s: %s", daemon_pid_file_ident, strerror(errno));
exit(-1);
} else {
dlog(LOG_DEBUG, 5, "opened pid file %s", daemon_pid_file_ident);
}
return pidfd;
}
static int open_and_lock_pid_file(char const *daemon_pid_file_ident)
{
dlog(LOG_DEBUG, 3, "radvd startup PID is %d", getpid());
int pidfd = open_pid_file(daemon_pid_file_ident);
int lock = flock(pidfd, LOCK_EX | LOCK_NB);
if (0 != lock) {
flog(LOG_ERR, "unable to lock pid file, %s: %s", daemon_pid_file_ident, strerror(errno));
exit(-1);
} else {
dlog(LOG_DEBUG, 4, "locked pid file %s", daemon_pid_file_ident);
}
return pidfd;
}
static int write_pid_file(char const *daemon_pid_file_ident, pid_t pid)
{
int pidfd = open_pid_file(daemon_pid_file_ident);
char pid_str[20] = {""};
sprintf(pid_str, "%d", pid);
dlog(LOG_DEBUG, 3, "radvd PID is %s", pid_str);
size_t len = strlen(pid_str);
int rc = write(pidfd, pid_str, len);
if (rc != (int)len) {
return -1;
}
char newline[] = {"\n"};
len = strlen(newline);
rc = write(pidfd, newline, len);
if (rc != (int)len) {
return -1;
}
rc = fsync(pidfd);
if (rc != 0) {
dlog(LOG_DEBUG, 4, "failed to fsync pid file: %s", daemon_pid_file_ident);
}
rc = close(pidfd);
if (rc != 0) {
dlog(LOG_DEBUG, 4, "failed to close pid file: %s", daemon_pid_file_ident);
}
char *dirstrcopy = strdup(daemon_pid_file_ident);
char *dirstr = dirname(dirstrcopy);
int dirfd = open(dirstr, O_RDONLY);
rc = fsync(dirfd);
if (rc != 0) {
dlog(LOG_DEBUG, 4, "failed to fsync pid dir: %s", dirstr);
}
rc = close(dirfd);
if (rc != 0) {
dlog(LOG_DEBUG, 4, "failed to close pid dir: %s", dirstr);
}
free(dirstrcopy);
dlog(LOG_DEBUG, 4, "wrote pid %d to pid file: %s", pid, daemon_pid_file_ident);
return rc;
}
static void check_pid_file(char const *daemon_pid_file_ident)
{
FILE *pidfile = fopen(daemon_pid_file_ident, "r");
if (!pidfile) {
flog(LOG_ERR, "unable to open pid file, %s: %s", daemon_pid_file_ident, strerror(errno));
exit(-1);
}
pid_t pid = -1;
int rc = fscanf(pidfile, "%d", &pid);
fclose(pidfile);
if (rc != 1) {
flog(LOG_ERR, "unable to read pid from pid file: %s", daemon_pid_file_ident);
exit(-1);
}
if (pid != getpid()) {
flog(LOG_ERR, "pid in file, %s, doesn't match getpid(): %d != %d", daemon_pid_file_ident, pid, getpid());
exit(-1);
}
dlog(LOG_DEBUG, 4, "validated pid file, %s: %d", daemon_pid_file_ident, pid);
}
static void timer_handler(int sock, struct Interface *iface)
{
dlog(LOG_DEBUG, 1, "timer_handler called for %s", iface->props.name);
if (send_ra_forall(sock, iface, NULL) != 0) {
dlog(LOG_DEBUG, 4, "send_ra_forall failed on interface %s", iface->props.name);
}
double next = rand_between(iface->MinRtrAdvInterval, iface->MaxRtrAdvInterval);
reschedule_iface(iface, next);
}
static void config_interface(struct Interface *iface)
{
if (iface->AdvLinkMTU)
set_interface_linkmtu(iface->props.name, iface->AdvLinkMTU);
if (iface->ra_header_info.AdvCurHopLimit)
set_interface_curhlim(iface->props.name, iface->ra_header_info.AdvCurHopLimit);
if (iface->ra_header_info.AdvReachableTime)
set_interface_reachtime(iface->props.name, iface->ra_header_info.AdvReachableTime);
if (iface->ra_header_info.AdvRetransTimer)
set_interface_retranstimer(iface->props.name, iface->ra_header_info.AdvRetransTimer);
}
/*
* send initial advertisement and set timers
*/
static void kickoff_adverts(int sock, struct Interface *iface)
{
clock_gettime(CLOCK_MONOTONIC, &iface->times.last_ra_time);
if (iface->UnicastOnly)
return;
clock_gettime(CLOCK_MONOTONIC, &iface->times.last_multicast);
/* send an initial advertisement */
if (send_ra_forall(sock, iface, NULL) != 0) {
dlog(LOG_DEBUG, 4, "send_ra_forall failed on interface %s", iface->props.name);
}
double next = min(MAX_INITIAL_RTR_ADVERT_INTERVAL, iface->MaxRtrAdvInterval);
reschedule_iface(iface, next);
}
static void stop_advert_foo(struct Interface *iface, void *data)
{
if (!iface->UnicastOnly) {
/* send a final advertisement with zero Router Lifetime */
dlog(LOG_DEBUG, 4, "stopping all adverts on %s", iface->props.name);
iface->state_info.cease_adv = 1;
int sock = *(int *)data;
send_ra_forall(sock, iface, NULL);
}
}
static void stop_adverts(int sock, struct Interface *ifaces)
{
flog(LOG_INFO, "sending stop adverts");
/*
* send final RA (a SHOULD in RFC4861 section 6.2.5)
*/
for_each_iface(ifaces, stop_advert_foo, &sock);
}
static void setup_iface_foo(struct Interface *iface, void *data)
{
int sock = *(int *)data;
if (setup_iface(sock, iface) < 0) {
if (iface->IgnoreIfMissing) {
dlog(LOG_DEBUG, 4, "interface %s does not exist or is not set up properly, ignoring the interface",
iface->props.name);
return;
} else {
flog(LOG_ERR, "interface %s does not exist or is not set up properly", iface->props.name);
exit(1);
}
}
config_interface(iface);
kickoff_adverts(sock, iface);
}
static void setup_ifaces(int sock, struct Interface *ifaces) { for_each_iface(ifaces, setup_iface_foo, &sock); }
static struct Interface *reload_config(int sock, struct Interface *ifaces, char const *conf_path)
{
free_ifaces(ifaces);
flog(LOG_INFO, "attempting to reread config file");
/* reread config file */
ifaces = readin_config(conf_path);
if (!ifaces) {
flog(LOG_ERR, "exiting, failed to read config file");
exit(1);
}
setup_ifaces(sock, ifaces);
flog(LOG_INFO, "resuming normal operation");
return ifaces;
}
static void sighup_handler(int sig) { sighup_received = 1; }
static void sigterm_handler(int sig)
{
++sigterm_received;
if (sigterm_received > 2) {
abort();
}
}
static void sigint_handler(int sig)
{
++sigint_received;
if (sigint_received > 2) {
abort();
}
}
static void sigusr1_handler(int sig) { sigusr1_received = 1; }
static void reset_prefix_lifetimes_foo(struct Interface *iface, void *data)
{
flog(LOG_INFO, "Resetting prefix lifetimes on %s", iface->props.name);
for (struct AdvPrefix *prefix = iface->AdvPrefixList; prefix; prefix = prefix->next) {
if (prefix->DecrementLifetimesFlag) {
char pfx_str[INET6_ADDRSTRLEN];
addrtostr(&prefix->Prefix, pfx_str, sizeof(pfx_str));
dlog(LOG_DEBUG, 4, "%s/%u%%%s plft reset from %u to %u secs", pfx_str, prefix->PrefixLen,
iface->props.name, prefix->curr_preferredlft, prefix->AdvPreferredLifetime);
dlog(LOG_DEBUG, 4, "%s/%u%%%s vlft reset from %u to %u secs", pfx_str, prefix->PrefixLen,
iface->props.name, prefix->curr_validlft, prefix->AdvValidLifetime);
prefix->curr_validlft = prefix->AdvValidLifetime;
prefix->curr_preferredlft = prefix->AdvPreferredLifetime;
}
}
}
static void reset_prefix_lifetimes(struct Interface *ifaces) { for_each_iface(ifaces, reset_prefix_lifetimes_foo, 0); }
static int drop_root_privileges(const char *username)
{
struct passwd *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", username, pw->pw_uid, pw->pw_gid);
return -1;
}
} else {
flog(LOG_ERR, "Couldn't find user '%.32s'", username);
return -1;
}
return 0;
}
static int check_conffile_perm(const char *username, const char *conf_file)
{
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);
if (!username)
username = "root";
struct passwd *pw = getpwnam(username);
if (!pw) {
return -1;
}
struct stat stbuf;
if (0 != stat(conf_file, &stbuf)) {
return -1;
}
if (stbuf.st_mode & S_IWOTH) {
flog(LOG_ERR, "Insecure file permissions (writable by others): %s", conf_file);
return -1;
}
/* for non-root: must not be writable by self/own group */
if (strncmp(username, "root", 5) != 0 && ((stbuf.st_mode & S_IWGRP && pw->pw_gid == stbuf.st_gid) ||
(stbuf.st_mode & S_IWUSR && pw->pw_uid == stbuf.st_uid))) {
flog(LOG_ERR, "Insecure file permissions (writable by self/group): %s", conf_file);
return -1;
}
return 0;
}
static 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 facility %d\n", LOG_FACILITY);
fprintf(stderr, "Please send bug reports or suggestions to %s.\n", CONTACT_EMAIL);
exit(1);
}
static void usage(char const *pname)
{
fprintf(stderr, "usage: %s %s\n", pname, usage_str);
exit(1);
}