ntptime.c revision 4e98c19603f13a48d194ec6f95e6c52339767d93
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Copyright (c) David L. Mills 1993, 1994
*
* Permission to use, copy, modify, and distribute this software and its
* documentation for any purpose and without fee is hereby granted, provided
* that the above copyright notice appears in all copies and that both the
* copyright notice and this permission notice appear in supporting
* documentation, and that the name University of Delaware not be used in
* advertising or publicity pertaining to distribution of the software
* without specific, written prior permission. The University of Delaware
* makes no representations about the suitability this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Modification history kern_ntptime.c
*
* 24 Sep 94 David L. Mills
* Tightened code at exits.
*
* 24 Mar 94 David L. Mills
* Revised syscall interface to include new variables for PPS
* time discipline.
*
* 14 Feb 94 David L. Mills
* Added code for external clock
*
* 28 Nov 93 David L. Mills
* Revised frequency scaling to conform with adjusted parameters
*
* 17 Sep 93 David L. Mills
* Created file
*/
/*
* ntp_gettime(), ntp_adjtime() - precision time interface
*
* These routines consitute the Network Time Protocol (NTP) interfaces
* for user and daemon application programs. The ntp_gettime() routine
* provides the time, maximum error (synch distance) and estimated error
* (dispersion) to client user application programs. The ntp_adjtime()
* routine is used by the NTP daemon to adjust the system clock to an
* externally derived time. The time offset and related variables set by
* this routine are used by clock() to adjust the phase and
* frequency of the phase-lock loop which controls the system clock.
*/
#include <sys/param.h>
#include <sys/user.h>
#include <sys/vnode.h>
#include <sys/proc.h>
#include <sys/time.h>
#include <sys/systm.h>
#include <sys/kmem.h>
#include <sys/cmn_err.h>
#include <sys/cpuvar.h>
#include <sys/timer.h>
#include <sys/debug.h>
#include <sys/timex.h>
#include <sys/model.h>
#include <sys/policy.h>
/*
* ntp_gettime() - NTP user application interface
*/
int
ntp_gettime(struct ntptimeval *tp)
{
timestruc_t tod;
struct ntptimeval ntv;
model_t datamodel = get_udatamodel();
gethrestime(&tod);
if (tod.tv_sec > TIME32_MAX)
return (set_errno(EOVERFLOW));
ntv.time.tv_sec = tod.tv_sec;
ntv.time.tv_usec = tod.tv_nsec / (NANOSEC / MICROSEC);
ntv.maxerror = time_maxerror;
ntv.esterror = time_esterror;
if (datamodel == DATAMODEL_NATIVE) {
if (copyout(&ntv, tp, sizeof (ntv)))
return (set_errno(EFAULT));
} else {
struct ntptimeval32 ntv32;
if (TIMEVAL_OVERFLOW(&ntv.time))
return (set_errno(EOVERFLOW));
TIMEVAL_TO_TIMEVAL32(&ntv32.time, &ntv.time);
ntv32.maxerror = ntv.maxerror;
ntv32.esterror = ntv.esterror;
if (copyout(&ntv32, tp, sizeof (ntv32)))
return (set_errno(EFAULT));
}
/*
* Status word error decode. If any of these conditions
* occur, an error is returned, instead of the status
* word. Most applications will care only about the fact
* the system clock may not be trusted, not about the
* details.
*
* Hardware or software error
*/
if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) ||
/*
* PPS signal lost when either time or frequency
* synchronization requested
*/
(time_status & (STA_PPSFREQ | STA_PPSTIME) &&
!(time_status & STA_PPSSIGNAL)) ||
/*
* PPS jitter exceeded when time synchronization
* requested
*/
(time_status & STA_PPSTIME && time_status & STA_PPSJITTER) ||
/*
* PPS wander exceeded or calibration error when
* frequency synchronization requested
*/
(time_status & STA_PPSFREQ && time_status &
(STA_PPSWANDER | STA_PPSERROR)))
return (TIME_ERROR);
return (time_state);
}
/*
* ntp_adjtime() - NTP daemon application interface
*/
int
ntp_adjtime(struct timex *tp)
{
struct timex ntv;
int modes;
if (copyin(tp, &ntv, sizeof (ntv)))
return (set_errno(EFAULT));
/*
* Update selected clock variables - only privileged users can
* change anything. Note that there is no error checking here on
* the assumption privileged users know what they're doing.
*/
modes = ntv.modes;
if (modes != 0 && secpolicy_settime(CRED()) != 0)
return (set_errno(EPERM));
if (ntv.constant < 0 || ntv.constant > 30)
return (set_errno(EINVAL));
mutex_enter(&tod_lock);
if (modes & MOD_MAXERROR)
time_maxerror = ntv.maxerror;
if (modes & MOD_ESTERROR)
time_esterror = ntv.esterror;
if (modes & MOD_STATUS) {
time_status &= STA_RONLY;
time_status |= ntv.status & ~STA_RONLY;
}
if (modes & MOD_TIMECONST)
time_constant = ntv.constant;
if (modes & MOD_OFFSET)
clock_update(ntv.offset);
if (modes & MOD_FREQUENCY)
time_freq = ntv.freq - pps_freq;
/*
* Retrieve all clock variables
*/
ntv.offset = time_offset / SCALE_UPDATE;
ntv.freq = time_freq + pps_freq;
ntv.maxerror = time_maxerror;
ntv.esterror = time_esterror;
ntv.status = time_status;
ntv.constant = time_constant;
ntv.precision = time_precision;
ntv.tolerance = time_tolerance;
ntv.shift = pps_shift;
ntv.ppsfreq = pps_freq;
ntv.jitter = pps_jitter >> PPS_AVG;
ntv.stabil = pps_stabil;
ntv.calcnt = pps_calcnt;
ntv.errcnt = pps_errcnt;
ntv.jitcnt = pps_jitcnt;
ntv.stbcnt = pps_stbcnt;
mutex_exit(&tod_lock);
if (copyout(&ntv, tp, sizeof (ntv)))
return (set_errno(EFAULT));
/*
* Status word error decode. See comments in
* ntp_gettime() routine.
*/
if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) ||
(time_status & (STA_PPSFREQ | STA_PPSTIME) &&
!(time_status & STA_PPSSIGNAL)) ||
(time_status & STA_PPSTIME &&
time_status & STA_PPSJITTER) ||
(time_status & STA_PPSFREQ &&
time_status & (STA_PPSWANDER | STA_PPSERROR)))
return (TIME_ERROR);
return (time_state);
}