ntp_adjtime.c revision 1.2.2.3
1 1.2.2.3 nathanw /* $NetBSD: ntp_adjtime.c,v 1.2.2.3 2002/01/28 20:51:28 nathanw Exp $ */ 2 1.2.2.2 nathanw 3 1.2.2.2 nathanw /* 4 1.2.2.2 nathanw * Copyright (c) 2001 The NetBSD Foundation, Inc. 5 1.2.2.2 nathanw * All rights reserved. 6 1.2.2.2 nathanw * 7 1.2.2.2 nathanw * This code is derived from software contributed to The NetBSD Foundation 8 1.2.2.2 nathanw * by Emmanuel Dreyfus. 9 1.2.2.2 nathanw * 10 1.2.2.2 nathanw * Redistribution and use in source and binary forms, with or without 11 1.2.2.2 nathanw * modification, are permitted provided that the following conditions 12 1.2.2.2 nathanw * are met: 13 1.2.2.2 nathanw * 1. Redistributions of source code must retain the above copyright 14 1.2.2.2 nathanw * notice, this list of conditions and the following disclaimer. 15 1.2.2.2 nathanw * 2. Redistributions in binary form must reproduce the above copyright 16 1.2.2.2 nathanw * notice, this list of conditions and the following disclaimer in the 17 1.2.2.2 nathanw * documentation and/or other materials provided with the distribution. 18 1.2.2.2 nathanw * 3. The name of the author may not be used to endorse or promote products 19 1.2.2.2 nathanw * derived from this software without specific prior written permission. 20 1.2.2.2 nathanw * 21 1.2.2.2 nathanw * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 1.2.2.2 nathanw * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 1.2.2.2 nathanw * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 1.2.2.2 nathanw * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 1.2.2.2 nathanw * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 1.2.2.2 nathanw * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 27 1.2.2.2 nathanw * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 1.2.2.2 nathanw * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 1.2.2.2 nathanw * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 1.2.2.2 nathanw * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 1.2.2.2 nathanw * SUCH DAMAGE. 32 1.2.2.2 nathanw */ 33 1.2.2.2 nathanw 34 1.2.2.2 nathanw #include "namespace.h" 35 1.2.2.3 nathanw #include <errno.h> 36 1.2.2.3 nathanw #include <fcntl.h> 37 1.2.2.3 nathanw #include <paths.h> 38 1.2.2.3 nathanw #include <unistd.h> 39 1.2.2.2 nathanw #include <sys/types.h> 40 1.2.2.2 nathanw #include <sys/time.h> 41 1.2.2.2 nathanw #include <sys/timex.h> 42 1.2.2.2 nathanw #include <sys/ioctl.h> 43 1.2.2.2 nathanw #include <sys/syscall.h> 44 1.2.2.3 nathanw #include <sys/systm.h> 45 1.2.2.3 nathanw 46 1.2.2.2 nathanw #include <sys/clockctl.h> 47 1.2.2.2 nathanw 48 1.2.2.2 nathanw #include <fcntl.h> 49 1.2.2.2 nathanw #include <paths.h> 50 1.2.2.2 nathanw #include <string.h> 51 1.2.2.2 nathanw #include <unistd.h> 52 1.2.2.2 nathanw 53 1.2.2.2 nathanw #ifdef __weak_alias 54 1.2.2.2 nathanw __weak_alias(ntp_adjtime,_ntp_adjtime) 55 1.2.2.2 nathanw #endif 56 1.2.2.2 nathanw 57 1.2.2.3 nathanw extern int __clockctl_fd; 58 1.2.2.3 nathanw 59 1.2.2.2 nathanw int 60 1.2.2.2 nathanw ntp_adjtime(tp) 61 1.2.2.2 nathanw struct timex *tp; 62 1.2.2.2 nathanw { 63 1.2.2.2 nathanw struct clockctl_ntp_adjtime_args args; 64 1.2.2.2 nathanw int error; 65 1.2.2.2 nathanw quad_t q; 66 1.2.2.2 nathanw int rv; 67 1.2.2.2 nathanw 68 1.2.2.3 nathanw /* 69 1.2.2.3 nathanw * if __clockctl_fd == -1, then this is not our first time, 70 1.2.2.3 nathanw * and we know root is the calling user. We use the system call 71 1.2.2.2 nathanw */ 72 1.2.2.3 nathanw if (__clockctl_fd == -1) { 73 1.2.2.3 nathanw try_syscall: 74 1.2.2.3 nathanw q = __syscall((quad_t)SYS_ntp_adjtime, tp); 75 1.2.2.3 nathanw if (/* LINTED constant */ sizeof (quad_t) == sizeof (register_t) 76 1.2.2.3 nathanw || /* LINTED constant */ BYTE_ORDER == LITTLE_ENDIAN) 77 1.2.2.3 nathanw rv = (int)q; 78 1.2.2.3 nathanw else 79 1.2.2.3 nathanw rv = (int)((u_quad_t)q >> 32); 80 1.2.2.3 nathanw 81 1.2.2.3 nathanw /* 82 1.2.2.3 nathanw * If credentials changed from root to an unprivilegied 83 1.2.2.3 nathanw * user, and we already had __clockctl_fd = -1, then we 84 1.2.2.3 nathanw * tried the system call as a non root user, it failed 85 1.2.2.3 nathanw * with EPERM, and we will try clockctl. 86 1.2.2.3 nathanw */ 87 1.2.2.3 nathanw if (rv != -1 || errno != EPERM) 88 1.2.2.3 nathanw return rv; 89 1.2.2.3 nathanw __clockctl_fd = -2; 90 1.2.2.3 nathanw } 91 1.2.2.3 nathanw 92 1.2.2.3 nathanw /* 93 1.2.2.3 nathanw * If __clockctl_fd = -2 then this is our first time here, 94 1.2.2.3 nathanw * or credentials have changed (the calling process dropped root 95 1.2.2.3 nathanw * root privilege). Check if root is the calling user. If it is, 96 1.2.2.3 nathanw * we try the system call, if it is not, we try clockctl. 97 1.2.2.3 nathanw */ 98 1.2.2.3 nathanw if (__clockctl_fd == -2) { 99 1.2.2.3 nathanw /* 100 1.2.2.3 nathanw * Root always uses the syscall 101 1.2.2.3 nathanw */ 102 1.2.2.3 nathanw if (geteuid() == 0) { 103 1.2.2.3 nathanw __clockctl_fd = -1; 104 1.2.2.3 nathanw goto try_syscall; 105 1.2.2.3 nathanw } 106 1.2.2.3 nathanw 107 1.2.2.3 nathanw /* 108 1.2.2.3 nathanw * If this fails, it means that we are not root 109 1.2.2.3 nathanw * and we cannot open clockctl. This is a failure. 110 1.2.2.3 nathanw */ 111 1.2.2.3 nathanw __clockctl_fd = open(_PATH_CLOCKCTL, O_WRONLY, 0); 112 1.2.2.3 nathanw if (__clockctl_fd == -1) 113 1.2.2.3 nathanw return -1; 114 1.2.2.3 nathanw } 115 1.2.2.2 nathanw 116 1.2.2.2 nathanw /* 117 1.2.2.3 nathanw * If __clockctl_fd >=0, clockctl has already been open 118 1.2.2.3 nathanw * and used, so we carry on using it. 119 1.2.2.2 nathanw */ 120 1.2.2.3 nathanw SCARG(&args.uas, tp) = tp; 121 1.2.2.3 nathanw error = ioctl(__clockctl_fd, CLOCKCTL_NTP_ADJTIME, &args); 122 1.2.2.3 nathanw 123 1.2.2.3 nathanw /* 124 1.2.2.3 nathanw * There is no way to get retval set through ioctl(), hence we 125 1.2.2.3 nathanw * have to handle it here, using args.retval 126 1.2.2.3 nathanw */ 127 1.2.2.3 nathanw if (error == 0) { 128 1.2.2.3 nathanw rv = (int)args.retval; 129 1.2.2.3 nathanw return rv; 130 1.2.2.2 nathanw } 131 1.2.2.3 nathanw return error; 132 1.2.2.2 nathanw 133 1.2.2.2 nathanw } 134
Indexes created Mon Sep 29 21:09:56 GMT 2025