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freebsd-skq/contrib/ntp/ntpd/ntpd.c
cy 1818eba70c MFV ntp 4.2.8p2 (r281348) 
Reviewed by:    delphij (suggested MFC)
Approved by:	roberto
Security:       CVE-2015-1798, CVE-2015-1799
Security:       VuXML ebd84c96-dd7e-11e4-854e-3c970e169bc2
MFC after:	1 month
2015-05-04 04:45:59 +00:00

1484 lines
32 KiB
C
Raw Blame History

/*
* ntpd.c - main program for the fixed point NTP daemon
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "ntp_machine.h"
#include "ntpd.h"
#include "ntp_io.h"
#include "ntp_stdlib.h"
#include <ntp_random.h>
#include "ntp_config.h"
#include "ntp_syslog.h"
#include "ntp_assert.h"
#include "isc/error.h"
#include "isc/strerror.h"
#include "isc/formatcheck.h"
#include "iosignal.h"
#ifdef SIM
# include "ntpsim.h"
#endif
#include "ntp_libopts.h"
#include "ntpd-opts.h"
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef HAVE_SYS_STAT_H
# include <sys/stat.h>
#endif
#include <stdio.h>
#ifdef HAVE_SYS_PARAM_H
# include <sys/param.h>
#endif
#ifdef HAVE_SYS_SIGNAL_H
# include <sys/signal.h>
#else
# include <signal.h>
#endif
#ifdef HAVE_SYS_IOCTL_H
# include <sys/ioctl.h>
#endif /* HAVE_SYS_IOCTL_H */
#if defined(HAVE_RTPRIO)
# ifdef HAVE_SYS_LOCK_H
# include <sys/lock.h>
# endif
# include <sys/rtprio.h>
#else
# ifdef HAVE_PLOCK
# ifdef HAVE_SYS_LOCK_H
# include <sys/lock.h>
# endif
# endif
#endif
#if defined(HAVE_SCHED_SETSCHEDULER)
# ifdef HAVE_SCHED_H
# include <sched.h>
# else
# ifdef HAVE_SYS_SCHED_H
# include <sys/sched.h>
# endif
# endif
#endif
#if defined(HAVE_SYS_MMAN_H)
# include <sys/mman.h>
#endif
#ifdef HAVE_TERMIOS_H
# include <termios.h>
#endif
#ifdef SYS_DOMAINOS
# include <apollo/base.h>
#endif /* SYS_DOMAINOS */
#include "recvbuff.h"
#include "ntp_cmdargs.h"
#if 0 /* HMS: I don't think we need this. 961223 */
#ifdef LOCK_PROCESS
# ifdef SYS_SOLARIS
# include <sys/mman.h>
# else
# include <sys/lock.h>
# endif
#endif
#endif
#ifdef _AIX
# include <ulimit.h>
#endif /* _AIX */
#ifdef SCO5_CLOCK
# include <sys/ci/ciioctl.h>
#endif
#ifdef HAVE_DROPROOT
# include <ctype.h>
# include <grp.h>
# include <pwd.h>
#ifdef HAVE_LINUX_CAPABILITIES
# include <sys/capability.h>
# include <sys/prctl.h>
#endif /* HAVE_LINUX_CAPABILITIES */
#if defined(HAVE_PRIV_H) && defined(HAVE_SOLARIS_PRIVS)
# include <priv.h>
#endif /* HAVE_PRIV_H */
#endif /* HAVE_DROPROOT */
#if defined (LIBSECCOMP) && (KERN_SECCOMP)
/* # include <sys/types.h> */
# include <sys/resource.h>
# include <seccomp.h>
#endif /* LIBSECCOMP and KERN_SECCOMP */
#ifdef HAVE_DNSREGISTRATION
# include <dns_sd.h>
DNSServiceRef mdns;
#endif
#ifdef HAVE_SETPGRP_0
# define ntp_setpgrp(x, y) setpgrp()
#else
# define ntp_setpgrp(x, y) setpgrp(x, y)
#endif
#ifdef HAVE_SOLARIS_PRIVS
# define LOWPRIVS "basic,sys_time,net_privaddr,proc_setid,!proc_info,!proc_session,!proc_exec"
static priv_set_t *lowprivs = NULL;
static priv_set_t *highprivs = NULL;
#endif /* HAVE_SOLARIS_PRIVS */
/*
* Scheduling priority we run at
*/
#define NTPD_PRIO (-12)
int priority_done = 2; /* 0 - Set priority */
/* 1 - priority is OK where it is */
/* 2 - Don't set priority */
/* 1 and 2 are pretty much the same */
int listen_to_virtual_ips = TRUE;
/*
* No-fork flag. If set, we do not become a background daemon.
*/
int nofork; /* Fork by default */
#ifdef HAVE_DNSREGISTRATION
/*
* mDNS registration flag. If set, we attempt to register with the mDNS system, but only
* after we have synched the first time. If the attempt fails, then try again once per
* minute for up to 5 times. After all, we may be starting before mDNS.
*/
int mdnsreg = FALSE;
int mdnstries = 5;
#endif /* HAVE_DNSREGISTRATION */
#ifdef HAVE_DROPROOT
int droproot;
int root_dropped;
char *user; /* User to switch to */
char *group; /* group to switch to */
const char *chrootdir; /* directory to chroot to */
uid_t sw_uid;
gid_t sw_gid;
char *endp;
struct group *gr;
struct passwd *pw;
#endif /* HAVE_DROPROOT */
#ifdef HAVE_WORKING_FORK
int waitsync_fd_to_close = -1; /* -w/--wait-sync */
#endif
/*
* Initializing flag. All async routines watch this and only do their
* thing when it is clear.
*/
int initializing;
/*
* Version declaration
*/
extern const char *Version;
char const *progname;
int was_alarmed;
#ifdef DECL_SYSCALL
/*
* We put this here, since the argument profile is syscall-specific
*/
extern int syscall (int, ...);
#endif /* DECL_SYSCALL */
#if !defined(SIM) && defined(SIGDIE1)
static RETSIGTYPE finish (int);
#endif
#if !defined(SIM) && defined(HAVE_WORKING_FORK)
static int wait_child_sync_if (int, long);
#endif
#if !defined(SIM) && !defined(SYS_WINNT)
# ifdef DEBUG
static RETSIGTYPE moredebug (int);
static RETSIGTYPE lessdebug (int);
# else /* !DEBUG follows */
static RETSIGTYPE no_debug (int);
# endif /* !DEBUG */
#endif /* !SIM && !SYS_WINNT */
int saved_argc;
char ** saved_argv;
#ifndef SIM
int ntpdmain (int, char **);
static void set_process_priority (void);
static void assertion_failed (const char *, int,
isc_assertiontype_t,
const char *)
__attribute__ ((__noreturn__));
static void library_fatal_error (const char *, int,
const char *, va_list)
ISC_FORMAT_PRINTF(3, 0);
static void library_unexpected_error(const char *, int,
const char *, va_list)
ISC_FORMAT_PRINTF(3, 0);
#endif /* !SIM */
void
parse_cmdline_opts(
int * pargc,
char ***pargv
)
{
static int parsed;
static int optct;
if (!parsed)
optct = ntpOptionProcess(&ntpdOptions, *pargc, *pargv);
parsed = 1;
*pargc -= optct;
*pargv += optct;
}
#ifdef SIM
int
main(
int argc,
char *argv[]
)
{
progname = argv[0];
parse_cmdline_opts(&argc, &argv);
#ifdef DEBUG
debug = OPT_VALUE_SET_DEBUG_LEVEL;
DPRINTF(1, ("%s\n", Version));
#endif
return ntpsim(argc, argv);
}
#else /* !SIM follows */
#ifdef NO_MAIN_ALLOWED
CALL(ntpd,"ntpd",ntpdmain);
#else /* !NO_MAIN_ALLOWED follows */
#ifndef SYS_WINNT
int
main(
int argc,
char *argv[]
)
{
return ntpdmain(argc, argv);
}
#endif /* !SYS_WINNT */
#endif /* !NO_MAIN_ALLOWED */
#endif /* !SIM */
#ifdef _AIX
/*
* OK. AIX is different than solaris in how it implements plock().
* If you do NOT adjust the stack limit, you will get the MAXIMUM
* stack size allocated and PINNED with you program. To check the
* value, use ulimit -a.
*
* To fix this, we create an automatic variable and set our stack limit
* to that PLUS 32KB of extra space (we need some headroom).
*
* This subroutine gets the stack address.
*
* Grover Davidson and Matt Ladendorf
*
*/
static char *
get_aix_stack(void)
{
char ch;
return (&ch);
}
/*
* Signal handler for SIGDANGER.
*/
static void
catch_danger(int signo)
{
msyslog(LOG_INFO, "ntpd: setpgid(): %m");
/* Make the system believe we'll free something, but don't do it! */
return;
}
#endif /* _AIX */
/*
* Set the process priority
*/
#ifndef SIM
static void
set_process_priority(void)
{
# ifdef DEBUG
if (debug > 1)
msyslog(LOG_DEBUG, "set_process_priority: %s: priority_done is <%d>",
((priority_done)
? "Leave priority alone"
: "Attempt to set priority"
),
priority_done);
# endif /* DEBUG */
# if defined(HAVE_SCHED_SETSCHEDULER)
if (!priority_done) {
extern int config_priority_override, config_priority;
int pmax, pmin;
struct sched_param sched;
pmax = sched_get_priority_max(SCHED_FIFO);
sched.sched_priority = pmax;
if ( config_priority_override ) {
pmin = sched_get_priority_min(SCHED_FIFO);
if ( config_priority > pmax )
sched.sched_priority = pmax;
else if ( config_priority < pmin )
sched.sched_priority = pmin;
else
sched.sched_priority = config_priority;
}
if ( sched_setscheduler(0, SCHED_FIFO, &sched) == -1 )
msyslog(LOG_ERR, "sched_setscheduler(): %m");
else
++priority_done;
}
# endif /* HAVE_SCHED_SETSCHEDULER */
# ifdef HAVE_RTPRIO
# ifdef RTP_SET
if (!priority_done) {
struct rtprio srtp;
srtp.type = RTP_PRIO_REALTIME; /* was: RTP_PRIO_NORMAL */
srtp.prio = 0; /* 0 (hi) -> RTP_PRIO_MAX (31,lo) */
if (rtprio(RTP_SET, getpid(), &srtp) < 0)
msyslog(LOG_ERR, "rtprio() error: %m");
else
++priority_done;
}
# else /* !RTP_SET follows */
if (!priority_done) {
if (rtprio(0, 120) < 0)
msyslog(LOG_ERR, "rtprio() error: %m");
else
++priority_done;
}
# endif /* !RTP_SET */
# endif /* HAVE_RTPRIO */
# if defined(NTPD_PRIO) && NTPD_PRIO != 0
# ifdef HAVE_ATT_NICE
if (!priority_done) {
errno = 0;
if (-1 == nice (NTPD_PRIO) && errno != 0)
msyslog(LOG_ERR, "nice() error: %m");
else
++priority_done;
}
# endif /* HAVE_ATT_NICE */
# ifdef HAVE_BSD_NICE
if (!priority_done) {
if (-1 == setpriority(PRIO_PROCESS, 0, NTPD_PRIO))
msyslog(LOG_ERR, "setpriority() error: %m");
else
++priority_done;
}
# endif /* HAVE_BSD_NICE */
# endif /* NTPD_PRIO && NTPD_PRIO != 0 */
if (!priority_done)
msyslog(LOG_ERR, "set_process_priority: No way found to improve our priority");
}
#endif /* !SIM */
/*
* Main program. Initialize us, disconnect us from the tty if necessary,
* and loop waiting for I/O and/or timer expiries.
*/
#ifndef SIM
int
ntpdmain(
int argc,
char *argv[]
)
{
l_fp now;
struct recvbuf *rbuf;
const char * logfilename;
# ifdef HAVE_UMASK
mode_t uv;
# endif
# if defined(HAVE_GETUID) && !defined(MPE) /* MPE lacks the concept of root */
uid_t uid;
# endif
# if defined(HAVE_WORKING_FORK)
long wait_sync = 0;
int pipe_fds[2];
int rc;
int exit_code;
# ifdef _AIX
struct sigaction sa;
# endif
# if !defined(HAVE_SETSID) && !defined (HAVE_SETPGID) && defined(TIOCNOTTY)
int fid;
# endif
# endif /* HAVE_WORKING_FORK*/
# ifdef SCO5_CLOCK
int fd;
int zero;
# endif
# ifdef HAVE_UMASK
uv = umask(0);
if (uv)
umask(uv);
else
umask(022);
# endif
saved_argc = argc;
saved_argv = argv;
progname = argv[0];
initializing = TRUE; /* mark that we are initializing */
parse_cmdline_opts(&argc, &argv);
# ifdef DEBUG
debug = OPT_VALUE_SET_DEBUG_LEVEL;
# ifdef HAVE_SETLINEBUF
setlinebuf(stdout);
# endif
# endif
if (HAVE_OPT(NOFORK) || HAVE_OPT(QUIT)
# ifdef DEBUG
|| debug
# endif
|| HAVE_OPT(SAVECONFIGQUIT))
nofork = TRUE;
init_logging(progname, NLOG_SYNCMASK, TRUE);
/* honor -l/--logfile option to log to a file */
if (HAVE_OPT(LOGFILE)) {
logfilename = OPT_ARG(LOGFILE);
syslogit = FALSE;
change_logfile(logfilename, FALSE);
} else {
logfilename = NULL;
if (nofork)
msyslog_term = TRUE;
if (HAVE_OPT(SAVECONFIGQUIT))
syslogit = FALSE;
}
msyslog(LOG_NOTICE, "%s: Starting", Version);
{
int i;
char buf[1024]; /* Secret knowledge of msyslog buf length */
char *cp = buf;
/* Note that every arg has an initial space character */
snprintf(cp, sizeof(buf), "Command line:");
cp += strlen(cp);
for (i = 0; i < saved_argc ; ++i) {
snprintf(cp, sizeof(buf) - (cp - buf),
" %s", saved_argv[i]);
cp += strlen(cp);
}
msyslog(LOG_INFO, "%s", buf);
}
/*
* Install trap handlers to log errors and assertion failures.
* Default handlers print to stderr which doesn't work if detached.
*/
isc_assertion_setcallback(assertion_failed);
isc_error_setfatal(library_fatal_error);
isc_error_setunexpected(library_unexpected_error);
/* MPE lacks the concept of root */
# if defined(HAVE_GETUID) && !defined(MPE)
uid = getuid();
if (uid && !HAVE_OPT( SAVECONFIGQUIT )) {
msyslog_term = TRUE;
msyslog(LOG_ERR,
"must be run as root, not uid %ld", (long)uid);
exit(1);
}
# endif
/*
* Enable the Multi-Media Timer for Windows?
*/
# ifdef SYS_WINNT
if (HAVE_OPT( MODIFYMMTIMER ))
set_mm_timer(MM_TIMER_HIRES);
# endif
#ifdef HAVE_DNSREGISTRATION
/*
* Enable mDNS registrations?
*/
if (HAVE_OPT( MDNS )) {
mdnsreg = TRUE;
}
#endif /* HAVE_DNSREGISTRATION */
if (HAVE_OPT( NOVIRTUALIPS ))
listen_to_virtual_ips = 0;
/*
* --interface, listen on specified interfaces
*/
if (HAVE_OPT( INTERFACE )) {
int ifacect = STACKCT_OPT( INTERFACE );
const char** ifaces = STACKLST_OPT( INTERFACE );
sockaddr_u addr;
while (ifacect-- > 0) {
add_nic_rule(
is_ip_address(*ifaces, AF_UNSPEC, &addr)
? MATCH_IFADDR
: MATCH_IFNAME,
*ifaces, -1, ACTION_LISTEN);
ifaces++;
}
}
if (HAVE_OPT( NICE ))
priority_done = 0;
# ifdef HAVE_SCHED_SETSCHEDULER
if (HAVE_OPT( PRIORITY )) {
config_priority = OPT_VALUE_PRIORITY;
config_priority_override = 1;
priority_done = 0;
}
# endif
# ifdef HAVE_WORKING_FORK
do { /* 'loop' once */
if (!HAVE_OPT( WAIT_SYNC ))
break;
wait_sync = OPT_VALUE_WAIT_SYNC;
if (wait_sync <= 0) {
wait_sync = 0;
break;
}
/* -w requires a fork() even with debug > 0 */
nofork = FALSE;
if (pipe(pipe_fds)) {
exit_code = (errno) ? errno : -1;
msyslog(LOG_ERR,
"Pipe creation failed for --wait-sync: %m");
exit(exit_code);
}
waitsync_fd_to_close = pipe_fds[1];
} while (0); /* 'loop' once */
# endif /* HAVE_WORKING_FORK */
init_lib();
# ifdef SYS_WINNT
/*
* Start interpolation thread, must occur before first
* get_systime()
*/
init_winnt_time();
# endif
/*
* Initialize random generator and public key pair
*/
get_systime(&now);
ntp_srandom((int)(now.l_i * now.l_uf));
/*
* Detach us from the terminal. May need an #ifndef GIZMO.
*/
if (!nofork) {
# ifdef HAVE_WORKING_FORK
rc = fork();
if (-1 == rc) {
exit_code = (errno) ? errno : -1;
msyslog(LOG_ERR, "fork: %m");
exit(exit_code);
}
if (rc > 0) {
/* parent */
exit_code = wait_child_sync_if(pipe_fds[0],
wait_sync);
exit(exit_code);
}
/*
* child/daemon
* close all open files excepting waitsync_fd_to_close.
* msyslog() unreliable until after init_logging().
*/
closelog();
if (syslog_file != NULL) {
fclose(syslog_file);
syslog_file = NULL;
syslogit = TRUE;
}
close_all_except(waitsync_fd_to_close);
INSIST(0 == open("/dev/null", 0) && 1 == dup2(0, 1) \
&& 2 == dup2(0, 2));
init_logging(progname, 0, TRUE);
/* we lost our logfile (if any) daemonizing */
setup_logfile(logfilename);
# ifdef SYS_DOMAINOS
{
uid_$t puid;
status_$t st;
proc2_$who_am_i(&puid);
proc2_$make_server(&puid, &st);
}
# endif /* SYS_DOMAINOS */
# ifdef HAVE_SETSID
if (setsid() == (pid_t)-1)
msyslog(LOG_ERR, "setsid(): %m");
# elif defined(HAVE_SETPGID)
if (setpgid(0, 0) == -1)
msyslog(LOG_ERR, "setpgid(): %m");
# else /* !HAVE_SETSID && !HAVE_SETPGID follows */
# ifdef TIOCNOTTY
fid = open("/dev/tty", 2);
if (fid >= 0) {
ioctl(fid, (u_long)TIOCNOTTY, NULL);
close(fid);
}
# endif /* TIOCNOTTY */
ntp_setpgrp(0, getpid());
# endif /* !HAVE_SETSID && !HAVE_SETPGID */
# ifdef _AIX
/* Don't get killed by low-on-memory signal. */
sa.sa_handler = catch_danger;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
sigaction(SIGDANGER, &sa, NULL);
# endif /* _AIX */
# endif /* HAVE_WORKING_FORK */
}
# ifdef SCO5_CLOCK
/*
* SCO OpenServer's system clock offers much more precise timekeeping
* on the base CPU than the other CPUs (for multiprocessor systems),
* so we must lock to the base CPU.
*/
fd = open("/dev/at1", O_RDONLY);
if (fd >= 0) {
zero = 0;
if (ioctl(fd, ACPU_LOCK, &zero) < 0)
msyslog(LOG_ERR, "cannot lock to base CPU: %m");
close(fd);
}
# endif
/* Setup stack size in preparation for locking pages in memory. */
# if defined(HAVE_MLOCKALL)
# ifdef HAVE_SETRLIMIT
ntp_rlimit(RLIMIT_STACK, DFLT_RLIMIT_STACK * 4096, 4096, "4k");
# ifdef RLIMIT_MEMLOCK
/*
* The default RLIMIT_MEMLOCK is very low on Linux systems.
* Unless we increase this limit malloc calls are likely to
* fail if we drop root privilege. To be useful the value
* has to be larger than the largest ntpd resident set size.
*/
ntp_rlimit(RLIMIT_MEMLOCK, DFLT_RLIMIT_MEMLOCK * 1024 * 1024, 1024 * 1024, "MB");
# endif /* RLIMIT_MEMLOCK */
# endif /* HAVE_SETRLIMIT */
# else /* !HAVE_MLOCKALL follows */
# ifdef HAVE_PLOCK
# ifdef PROCLOCK
# ifdef _AIX
/*
* set the stack limit for AIX for plock().
* see get_aix_stack() for more info.
*/
if (ulimit(SET_STACKLIM, (get_aix_stack() - 8 * 4096)) < 0)
msyslog(LOG_ERR,
"Cannot adjust stack limit for plock: %m");
# endif /* _AIX */
# endif /* PROCLOCK */
# endif /* HAVE_PLOCK */
# endif /* !HAVE_MLOCKALL */
/*
* Set up signals we pay attention to locally.
*/
# ifdef SIGDIE1
signal_no_reset(SIGDIE1, finish);
signal_no_reset(SIGDIE2, finish);
signal_no_reset(SIGDIE3, finish);
signal_no_reset(SIGDIE4, finish);
# endif
# ifdef SIGBUS
signal_no_reset(SIGBUS, finish);
# endif
# if !defined(SYS_WINNT) && !defined(VMS)
# ifdef DEBUG
(void) signal_no_reset(MOREDEBUGSIG, moredebug);
(void) signal_no_reset(LESSDEBUGSIG, lessdebug);
# else
(void) signal_no_reset(MOREDEBUGSIG, no_debug);
(void) signal_no_reset(LESSDEBUGSIG, no_debug);
# endif /* DEBUG */
# endif /* !SYS_WINNT && !VMS */
/*
* Set up signals we should never pay attention to.
*/
# ifdef SIGPIPE
signal_no_reset(SIGPIPE, SIG_IGN);
# endif
/*
* Call the init_ routines to initialize the data structures.
*
* Exactly what command-line options are we expecting here?
*/
INIT_SSL();
init_auth();
init_util();
init_restrict();
init_mon();
init_timer();
init_request();
init_control();
init_peer();
# ifdef REFCLOCK
init_refclock();
# endif
set_process_priority();
init_proto(); /* Call at high priority */
init_io();
init_loopfilter();
mon_start(MON_ON); /* monitor on by default now */
/* turn off in config if unwanted */
/*
* Get the configuration. This is done in a separate module
* since this will definitely be different for the gizmo board.
*/
getconfig(argc, argv);
if (do_memlock) {
# if defined(HAVE_MLOCKALL)
/*
* lock the process into memory
*/
if (!HAVE_OPT(SAVECONFIGQUIT) &&
0 != mlockall(MCL_CURRENT|MCL_FUTURE))
msyslog(LOG_ERR, "mlockall(): %m");
# else /* !HAVE_MLOCKALL follows */
# ifdef HAVE_PLOCK
# ifdef PROCLOCK
/*
* lock the process into memory
*/
if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(PROCLOCK))
msyslog(LOG_ERR, "plock(PROCLOCK): %m");
# else /* !PROCLOCK follows */
# ifdef TXTLOCK
/*
* Lock text into ram
*/
if (!HAVE_OPT(SAVECONFIGQUIT) && 0 != plock(TXTLOCK))
msyslog(LOG_ERR, "plock(TXTLOCK) error: %m");
# else /* !TXTLOCK follows */
msyslog(LOG_ERR, "plock() - don't know what to lock!");
# endif /* !TXTLOCK */
# endif /* !PROCLOCK */
# endif /* HAVE_PLOCK */
# endif /* !HAVE_MLOCKALL */
}
loop_config(LOOP_DRIFTINIT, 0);
report_event(EVNT_SYSRESTART, NULL, NULL);
initializing = FALSE;
# ifdef HAVE_DROPROOT
if (droproot) {
/* Drop super-user privileges and chroot now if the OS supports this */
# ifdef HAVE_LINUX_CAPABILITIES
/* set flag: keep privileges accross setuid() call (we only really need cap_sys_time): */
if (prctl( PR_SET_KEEPCAPS, 1L, 0L, 0L, 0L ) == -1) {
msyslog( LOG_ERR, "prctl( PR_SET_KEEPCAPS, 1L ) failed: %m" );
exit(-1);
}
# elif HAVE_SOLARIS_PRIVS
/* Nothing to do here */
# else
/* we need a user to switch to */
if (user == NULL) {
msyslog(LOG_ERR, "Need user name to drop root privileges (see -u flag!)" );
exit(-1);
}
# endif /* HAVE_LINUX_CAPABILITIES || HAVE_SOLARIS_PRIVS */
if (user != NULL) {
if (isdigit((unsigned char)*user)) {
sw_uid = (uid_t)strtoul(user, &endp, 0);
if (*endp != '\0')
goto getuser;
if ((pw = getpwuid(sw_uid)) != NULL) {
free(user);
user = estrdup(pw->pw_name);
sw_gid = pw->pw_gid;
} else {
errno = 0;
msyslog(LOG_ERR, "Cannot find user ID %s", user);
exit (-1);
}
} else {
getuser:
errno = 0;
if ((pw = getpwnam(user)) != NULL) {
sw_uid = pw->pw_uid;
sw_gid = pw->pw_gid;
} else {
if (errno)
msyslog(LOG_ERR, "getpwnam(%s) failed: %m", user);
else
msyslog(LOG_ERR, "Cannot find user `%s'", user);
exit (-1);
}
}
}
if (group != NULL) {
if (isdigit((unsigned char)*group)) {
sw_gid = (gid_t)strtoul(group, &endp, 0);
if (*endp != '\0')
goto getgroup;
} else {
getgroup:
if ((gr = getgrnam(group)) != NULL) {
sw_gid = gr->gr_gid;
} else {
errno = 0;
msyslog(LOG_ERR, "Cannot find group `%s'", group);
exit (-1);
}
}
}
if (chrootdir ) {
/* make sure cwd is inside the jail: */
if (chdir(chrootdir)) {
msyslog(LOG_ERR, "Cannot chdir() to `%s': %m", chrootdir);
exit (-1);
}
if (chroot(chrootdir)) {
msyslog(LOG_ERR, "Cannot chroot() to `%s': %m", chrootdir);
exit (-1);
}
if (chdir("/")) {
msyslog(LOG_ERR, "Cannot chdir() to`root after chroot(): %m");
exit (-1);
}
}
# ifdef HAVE_SOLARIS_PRIVS
if ((lowprivs = priv_str_to_set(LOWPRIVS, ",", NULL)) == NULL) {
msyslog(LOG_ERR, "priv_str_to_set() failed:%m");
exit(-1);
}
if ((highprivs = priv_allocset()) == NULL) {
msyslog(LOG_ERR, "priv_allocset() failed:%m");
exit(-1);
}
(void) getppriv(PRIV_PERMITTED, highprivs);
(void) priv_intersect(highprivs, lowprivs);
if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
msyslog(LOG_ERR, "setppriv() failed:%m");
exit(-1);
}
# endif /* HAVE_SOLARIS_PRIVS */
if (user && initgroups(user, sw_gid)) {
msyslog(LOG_ERR, "Cannot initgroups() to user `%s': %m", user);
exit (-1);
}
if (group && setgid(sw_gid)) {
msyslog(LOG_ERR, "Cannot setgid() to group `%s': %m", group);
exit (-1);
}
if (group && setegid(sw_gid)) {
msyslog(LOG_ERR, "Cannot setegid() to group `%s': %m", group);
exit (-1);
}
if (group)
setgroups(1, &sw_gid);
else
initgroups(pw->pw_name, pw->pw_gid);
if (user && setuid(sw_uid)) {
msyslog(LOG_ERR, "Cannot setuid() to user `%s': %m", user);
exit (-1);
}
if (user && seteuid(sw_uid)) {
msyslog(LOG_ERR, "Cannot seteuid() to user `%s': %m", user);
exit (-1);
}
# if !defined(HAVE_LINUX_CAPABILITIES) && !defined(HAVE_SOLARIS_PRIVS)
/*
* for now assume that the privilege to bind to privileged ports
* is associated with running with uid 0 - should be refined on
* ports that allow binding to NTP_PORT with uid != 0
*/
disable_dynamic_updates |= (sw_uid != 0); /* also notifies routing message listener */
# endif /* !HAVE_LINUX_CAPABILITIES && !HAVE_SOLARIS_PRIVS */
if (disable_dynamic_updates && interface_interval) {
interface_interval = 0;
msyslog(LOG_INFO, "running as non-root disables dynamic interface tracking");
}
# ifdef HAVE_LINUX_CAPABILITIES
{
/*
* We may be running under non-root uid now, but we still hold full root privileges!
* We drop all of them, except for the crucial one or two: cap_sys_time and
* cap_net_bind_service if doing dynamic interface tracking.
*/
cap_t caps;
char *captext;
captext = (0 != interface_interval)
? "cap_sys_time,cap_net_bind_service=pe"
: "cap_sys_time=pe";
caps = cap_from_text(captext);
if (!caps) {
msyslog(LOG_ERR,
"cap_from_text(%s) failed: %m",
captext);
exit(-1);
}
if (-1 == cap_set_proc(caps)) {
msyslog(LOG_ERR,
"cap_set_proc() failed to drop root privs: %m");
exit(-1);
}
cap_free(caps);
}
# endif /* HAVE_LINUX_CAPABILITIES */
# ifdef HAVE_SOLARIS_PRIVS
if (priv_delset(lowprivs, "proc_setid") == -1) {
msyslog(LOG_ERR, "priv_delset() failed:%m");
exit(-1);
}
if (setppriv(PRIV_SET, PRIV_PERMITTED, lowprivs) == -1) {
msyslog(LOG_ERR, "setppriv() failed:%m");
exit(-1);
}
priv_freeset(lowprivs);
priv_freeset(highprivs);
# endif /* HAVE_SOLARIS_PRIVS */
root_dropped = TRUE;
fork_deferred_worker();
} /* if (droproot) */
# endif /* HAVE_DROPROOT */
/* libssecomp sandboxing */
#if defined (LIBSECCOMP) && (KERN_SECCOMP)
scmp_filter_ctx ctx;
if ((ctx = seccomp_init(SCMP_ACT_KILL)) < 0)
msyslog(LOG_ERR, "%s: seccomp_init(SCMP_ACT_KILL) failed: %m", __func__);
else {
msyslog(LOG_DEBUG, "%s: seccomp_init(SCMP_ACT_KILL) succeeded", __func__);
}
#ifdef __x86_64__
int scmp_sc[] = {
SCMP_SYS(adjtimex),
SCMP_SYS(bind),
SCMP_SYS(brk),
SCMP_SYS(chdir),
SCMP_SYS(clock_gettime),
SCMP_SYS(clock_settime),
SCMP_SYS(close),
SCMP_SYS(connect),
SCMP_SYS(exit_group),
SCMP_SYS(fstat),
SCMP_SYS(fsync),
SCMP_SYS(futex),
SCMP_SYS(getitimer),
SCMP_SYS(getsockname),
SCMP_SYS(ioctl),
SCMP_SYS(lseek),
SCMP_SYS(madvise),
SCMP_SYS(mmap),
SCMP_SYS(munmap),
SCMP_SYS(open),
SCMP_SYS(poll),
SCMP_SYS(read),
SCMP_SYS(recvmsg),
SCMP_SYS(rename),
SCMP_SYS(rt_sigaction),
SCMP_SYS(rt_sigprocmask),
SCMP_SYS(rt_sigreturn),
SCMP_SYS(select),
SCMP_SYS(sendto),
SCMP_SYS(setitimer),
SCMP_SYS(setsid),
SCMP_SYS(socket),
SCMP_SYS(stat),
SCMP_SYS(time),
SCMP_SYS(write),
};
#endif
#ifdef __i386__
int scmp_sc[] = {
SCMP_SYS(_newselect),
SCMP_SYS(adjtimex),
SCMP_SYS(brk),
SCMP_SYS(chdir),
SCMP_SYS(clock_gettime),
SCMP_SYS(clock_settime),
SCMP_SYS(close),
SCMP_SYS(exit_group),
SCMP_SYS(fsync),
SCMP_SYS(futex),
SCMP_SYS(getitimer),
SCMP_SYS(madvise),
SCMP_SYS(mmap),
SCMP_SYS(mmap2),
SCMP_SYS(munmap),
SCMP_SYS(open),
SCMP_SYS(poll),
SCMP_SYS(read),
SCMP_SYS(rename),
SCMP_SYS(rt_sigaction),
SCMP_SYS(rt_sigprocmask),
SCMP_SYS(select),
SCMP_SYS(setitimer),
SCMP_SYS(setsid),
SCMP_SYS(sigprocmask),
SCMP_SYS(sigreturn),
SCMP_SYS(socketcall),
SCMP_SYS(stat64),
SCMP_SYS(time),
SCMP_SYS(write),
};
#endif
{
int i;
for (i = 0; i < COUNTOF(scmp_sc); i++) {
if (seccomp_rule_add(ctx,
SCMP_ACT_ALLOW, scmp_sc[i], 0) < 0) {
msyslog(LOG_ERR,
"%s: seccomp_rule_add() failed: %m",
__func__);
}
}
}
if (seccomp_load(ctx) < 0)
msyslog(LOG_ERR, "%s: seccomp_load() failed: %m",
__func__);
else {
msyslog(LOG_DEBUG, "%s: seccomp_load() succeeded", __func__);
}
#endif /* LIBSECCOMP and KERN_SECCOMP */
# ifdef HAVE_IO_COMPLETION_PORT
for (;;) {
GetReceivedBuffers();
# else /* normal I/O */
BLOCK_IO_AND_ALARM();
was_alarmed = FALSE;
for (;;) {
if (alarm_flag) { /* alarmed? */
was_alarmed = TRUE;
alarm_flag = FALSE;
}
if (!was_alarmed && !has_full_recv_buffer()) {
/*
* Nothing to do. Wait for something.
*/
io_handler();
}
if (alarm_flag) { /* alarmed? */
was_alarmed = TRUE;
alarm_flag = FALSE;
}
if (was_alarmed) {
UNBLOCK_IO_AND_ALARM();
/*
* Out here, signals are unblocked. Call timer routine
* to process expiry.
*/
timer();
was_alarmed = FALSE;
BLOCK_IO_AND_ALARM();
}
# endif /* !HAVE_IO_COMPLETION_PORT */
# ifdef DEBUG_TIMING
{
l_fp pts;
l_fp tsa, tsb;
int bufcount = 0;
get_systime(&pts);
tsa = pts;
# endif
rbuf = get_full_recv_buffer();
while (rbuf != NULL) {
if (alarm_flag) {
was_alarmed = TRUE;
alarm_flag = FALSE;
}
UNBLOCK_IO_AND_ALARM();
if (was_alarmed) {
/* avoid timer starvation during lengthy I/O handling */
timer();
was_alarmed = FALSE;
}
/*
* Call the data procedure to handle each received
* packet.
*/
if (rbuf->receiver != NULL) {
# ifdef DEBUG_TIMING
l_fp dts = pts;
L_SUB(&dts, &rbuf->recv_time);
DPRINTF(2, ("processing timestamp delta %s (with prec. fuzz)\n", lfptoa(&dts, 9)));
collect_timing(rbuf, "buffer processing delay", 1, &dts);
bufcount++;
# endif
(*rbuf->receiver)(rbuf);
} else {
msyslog(LOG_ERR, "fatal: receive buffer callback NULL");
abort();
}
BLOCK_IO_AND_ALARM();
freerecvbuf(rbuf);
rbuf = get_full_recv_buffer();
}
# ifdef DEBUG_TIMING
get_systime(&tsb);
L_SUB(&tsb, &tsa);
if (bufcount) {
collect_timing(NULL, "processing", bufcount, &tsb);
DPRINTF(2, ("processing time for %d buffers %s\n", bufcount, lfptoa(&tsb, 9)));
}
}
# endif
/*
* Go around again
*/
# ifdef HAVE_DNSREGISTRATION
if (mdnsreg && (current_time - mdnsreg ) > 60 && mdnstries && sys_leap != LEAP_NOTINSYNC) {
mdnsreg = current_time;
msyslog(LOG_INFO, "Attempting to register mDNS");
if ( DNSServiceRegister (&mdns, 0, 0, NULL, "_ntp._udp", NULL, NULL,
htons(NTP_PORT), 0, NULL, NULL, NULL) != kDNSServiceErr_NoError ) {
if (!--mdnstries) {
msyslog(LOG_ERR, "Unable to register mDNS, giving up.");
} else {
msyslog(LOG_INFO, "Unable to register mDNS, will try later.");
}
} else {
msyslog(LOG_INFO, "mDNS service registered.");
mdnsreg = FALSE;
}
}
# endif /* HAVE_DNSREGISTRATION */
}
UNBLOCK_IO_AND_ALARM();
return 1;
}
#endif /* !SIM */
#if !defined(SIM) && defined(SIGDIE1)
/*
* finish - exit gracefully
*/
static RETSIGTYPE
finish(
int sig
)
{
const char *sig_desc;
sig_desc = NULL;
#ifdef HAVE_STRSIGNAL
sig_desc = strsignal(sig);
#endif
if (sig_desc == NULL)
sig_desc = "";
msyslog(LOG_NOTICE, "%s exiting on signal %d (%s)", progname,
sig, sig_desc);
/* See Bug 2513 and Bug 2522 re the unlink of PIDFILE */
# ifdef HAVE_DNSREGISTRATION
if (mdns != NULL)
DNSServiceRefDeallocate(mdns);
# endif
peer_cleanup();
exit(0);
}
#endif /* !SIM && SIGDIE1 */
#ifndef SIM
/*
* wait_child_sync_if - implements parent side of -w/--wait-sync
*/
# ifdef HAVE_WORKING_FORK
static int
wait_child_sync_if(
int pipe_read_fd,
long wait_sync
)
{
int rc;
int exit_code;
time_t wait_end_time;
time_t cur_time;
time_t wait_rem;
fd_set readset;
struct timeval wtimeout;
if (0 == wait_sync)
return 0;
/* waitsync_fd_to_close used solely by child */
close(waitsync_fd_to_close);
wait_end_time = time(NULL) + wait_sync;
do {
cur_time = time(NULL);
wait_rem = (wait_end_time > cur_time)
? (wait_end_time - cur_time)
: 0;
wtimeout.tv_sec = wait_rem;
wtimeout.tv_usec = 0;
FD_ZERO(&readset);
FD_SET(pipe_read_fd, &readset);
rc = select(pipe_read_fd + 1, &readset, NULL, NULL,
&wtimeout);
if (-1 == rc) {
if (EINTR == errno)
continue;
exit_code = (errno) ? errno : -1;
msyslog(LOG_ERR,
"--wait-sync select failed: %m");
return exit_code;
}
if (0 == rc) {
/*
* select() indicated a timeout, but in case
* its timeouts are affected by a step of the
* system clock, select() again with a zero
* timeout to confirm.
*/
FD_ZERO(&readset);
FD_SET(pipe_read_fd, &readset);
wtimeout.tv_sec = 0;
wtimeout.tv_usec = 0;
rc = select(pipe_read_fd + 1, &readset, NULL,
NULL, &wtimeout);
if (0 == rc) /* select() timeout */
break;
else /* readable */
return 0;
} else /* readable */
return 0;
} while (wait_rem > 0);
fprintf(stderr, "%s: -w/--wait-sync %ld timed out.\n",
progname, wait_sync);
return ETIMEDOUT;
}
# endif /* HAVE_WORKING_FORK */
/*
* assertion_failed - Redirect assertion failures to msyslog().
*/
static void
assertion_failed(
const char *file,
int line,
isc_assertiontype_t type,
const char *cond
)
{
isc_assertion_setcallback(NULL); /* Avoid recursion */
msyslog(LOG_ERR, "%s:%d: %s(%s) failed",
file, line, isc_assertion_typetotext(type), cond);
msyslog(LOG_ERR, "exiting (due to assertion failure)");
#if defined(DEBUG) && defined(SYS_WINNT)
if (debug)
DebugBreak();
#endif
abort();
}
/*
* library_fatal_error - Handle fatal errors from our libraries.
*/
static void
library_fatal_error(
const char *file,
int line,
const char *format,
va_list args
)
{
char errbuf[256];
isc_error_setfatal(NULL); /* Avoid recursion */
msyslog(LOG_ERR, "%s:%d: fatal error:", file, line);
vsnprintf(errbuf, sizeof(errbuf), format, args);
msyslog(LOG_ERR, "%s", errbuf);
msyslog(LOG_ERR, "exiting (due to fatal error in library)");
#if defined(DEBUG) && defined(SYS_WINNT)
if (debug)
DebugBreak();
#endif
abort();
}
/*
* library_unexpected_error - Handle non fatal errors from our libraries.
*/
# define MAX_UNEXPECTED_ERRORS 100
int unexpected_error_cnt = 0;
static void
library_unexpected_error(
const char *file,
int line,
const char *format,
va_list args
)
{
char errbuf[256];
if (unexpected_error_cnt >= MAX_UNEXPECTED_ERRORS)
return; /* avoid clutter in log */
msyslog(LOG_ERR, "%s:%d: unexpected error:", file, line);
vsnprintf(errbuf, sizeof(errbuf), format, args);
msyslog(LOG_ERR, "%s", errbuf);
if (++unexpected_error_cnt == MAX_UNEXPECTED_ERRORS)
msyslog(LOG_ERR, "Too many errors. Shutting up.");
}
#endif /* !SIM */
#if !defined(SIM) && !defined(SYS_WINNT)
# ifdef DEBUG
/*
* moredebug - increase debugging verbosity
*/
static RETSIGTYPE
moredebug(
int sig
)
{
int saved_errno = errno;
if (debug < 255)
{
debug++;
msyslog(LOG_DEBUG, "debug raised to %d", debug);
}
errno = saved_errno;
}
/*
* lessdebug - decrease debugging verbosity
*/
static RETSIGTYPE
lessdebug(
int sig
)
{
int saved_errno = errno;
if (debug > 0)
{
debug--;
msyslog(LOG_DEBUG, "debug lowered to %d", debug);
}
errno = saved_errno;
}
# else /* !DEBUG follows */
/*
* no_debug - We don't do the debug here.
*/
static RETSIGTYPE
no_debug(
int sig
)
{
int saved_errno = errno;
msyslog(LOG_DEBUG, "ntpd not compiled for debugging (signal %d)", sig);
errno = saved_errno;
}
# endif /* !DEBUG */
#endif /* !SIM && !SYS_WINNT */
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