134 lines
3.9 KiB
C
134 lines
3.9 KiB
C
/* $NetBSD: ntp_adjtime.c,v 1.3 2001/12/09 16:11:45 manu Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 2001 The NetBSD Foundation, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to The NetBSD Foundation
|
|
* by Emmanuel Dreyfus.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
|
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include "namespace.h"
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <paths.h>
|
|
#include <unistd.h>
|
|
#include <sys/types.h>
|
|
#include <sys/time.h>
|
|
#include <sys/timex.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/syscall.h>
|
|
#include <sys/systm.h>
|
|
|
|
#include <sys/clockctl.h>
|
|
|
|
#include <fcntl.h>
|
|
#include <paths.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#ifdef __weak_alias
|
|
__weak_alias(ntp_adjtime,_ntp_adjtime)
|
|
#endif
|
|
|
|
extern int __clockctl_fd;
|
|
|
|
int
|
|
ntp_adjtime(tp)
|
|
struct timex *tp;
|
|
{
|
|
struct clockctl_ntp_adjtime_args args;
|
|
int error;
|
|
quad_t q;
|
|
int rv;
|
|
|
|
/*
|
|
* if __clockctl_fd == -1, then this is not our first time,
|
|
* and we know root is the calling user. We use the system call
|
|
*/
|
|
if (__clockctl_fd == -1) {
|
|
try_syscall:
|
|
q = __syscall((quad_t)SYS_ntp_adjtime, tp);
|
|
if (/* LINTED constant */ sizeof (quad_t) == sizeof (register_t)
|
|
|| /* LINTED constant */ BYTE_ORDER == LITTLE_ENDIAN)
|
|
rv = (int)q;
|
|
else
|
|
rv = (int)((u_quad_t)q >> 32);
|
|
|
|
/*
|
|
* If credentials changed from root to an unprivilegied
|
|
* user, and we already had __clockctl_fd = -1, then we
|
|
* tried the system call as a non root user, it failed
|
|
* with EPERM, and we will try clockctl.
|
|
*/
|
|
if (rv != -1 || errno != EPERM)
|
|
return rv;
|
|
__clockctl_fd = -2;
|
|
}
|
|
|
|
/*
|
|
* If __clockctl_fd = -2 then this is our first time here,
|
|
* or credentials have changed (the calling process dropped root
|
|
* root privilege). Check if root is the calling user. If it is,
|
|
* we try the system call, if it is not, we try clockctl.
|
|
*/
|
|
if (__clockctl_fd == -2) {
|
|
/*
|
|
* Root always uses the syscall
|
|
*/
|
|
if (geteuid() == 0) {
|
|
__clockctl_fd = -1;
|
|
goto try_syscall;
|
|
}
|
|
|
|
/*
|
|
* If this fails, it means that we are not root
|
|
* and we cannot open clockctl. This is a failure.
|
|
*/
|
|
__clockctl_fd = open(_PATH_CLOCKCTL, O_WRONLY, 0);
|
|
if (__clockctl_fd == -1)
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* If __clockctl_fd >=0, clockctl has already been open
|
|
* and used, so we carry on using it.
|
|
*/
|
|
SCARG(&args.uas, tp) = tp;
|
|
error = ioctl(__clockctl_fd, CLOCKCTL_NTP_ADJTIME, &args);
|
|
|
|
/*
|
|
* There is no way to get retval set through ioctl(), hence we
|
|
* have to handle it here, using args.retval
|
|
*/
|
|
if (error == 0) {
|
|
rv = (int)args.retval;
|
|
return rv;
|
|
}
|
|
return error;
|
|
|
|
}
|