adjtime.c revision 1.2.2.3
1 1.2.2.3 nathanw /* $NetBSD: adjtime.c,v 1.2.2.3 2002/01/28 20:51:26 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 1.2.2.2 nathanw #include <fcntl.h> 37 1.2.2.2 nathanw #include <paths.h> 38 1.2.2.2 nathanw #include <unistd.h> 39 1.2.2.2 nathanw #include <time.h> 40 1.2.2.2 nathanw #include <string.h> 41 1.2.2.2 nathanw #include <sys/types.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 #ifdef __weak_alias 49 1.2.2.2 nathanw __weak_alias(adjtime,_adjtime) 50 1.2.2.2 nathanw #endif 51 1.2.2.2 nathanw 52 1.2.2.3 nathanw extern int __clockctl_fd; 53 1.2.2.3 nathanw 54 1.2.2.2 nathanw int 55 1.2.2.2 nathanw adjtime(delta, olddelta) 56 1.2.2.2 nathanw const struct timeval *delta; 57 1.2.2.2 nathanw struct timeval *olddelta; 58 1.2.2.2 nathanw { 59 1.2.2.3 nathanw struct sys_adjtime_args args; 60 1.2.2.2 nathanw int error; 61 1.2.2.2 nathanw quad_t q; 62 1.2.2.2 nathanw int rv; 63 1.2.2.2 nathanw 64 1.2.2.3 nathanw /* 65 1.2.2.3 nathanw * if __clockctl_fd == -1, then this is not our first time, 66 1.2.2.3 nathanw * and we know root is the calling user. We use the system call 67 1.2.2.3 nathanw */ 68 1.2.2.3 nathanw if (__clockctl_fd == -1) { 69 1.2.2.3 nathanw try_syscall: 70 1.2.2.3 nathanw q = __syscall((quad_t)SYS_adjtime, delta, olddelta); 71 1.2.2.3 nathanw if (/* LINTED constant */ sizeof (quad_t) == sizeof (register_t) 72 1.2.2.3 nathanw || /* LINTED constant */ BYTE_ORDER == LITTLE_ENDIAN) 73 1.2.2.3 nathanw rv = (int)q; 74 1.2.2.3 nathanw else 75 1.2.2.3 nathanw rv = (int)((u_quad_t)q >> 32); 76 1.2.2.3 nathanw 77 1.2.2.3 nathanw /* 78 1.2.2.3 nathanw * If credentials changed from root to an unprivilegied 79 1.2.2.3 nathanw * user, and we already had __clockctl_fd = -1, then we 80 1.2.2.3 nathanw * tried the system call as a non root user, it failed 81 1.2.2.3 nathanw * with EPERM, and we will try clockctl. 82 1.2.2.3 nathanw */ 83 1.2.2.3 nathanw if (rv != -1 || errno != EPERM) 84 1.2.2.3 nathanw return rv; 85 1.2.2.3 nathanw __clockctl_fd = -2; 86 1.2.2.3 nathanw } 87 1.2.2.3 nathanw 88 1.2.2.3 nathanw /* 89 1.2.2.3 nathanw * If __clockctl_fd = -2 then this is our first time here, 90 1.2.2.3 nathanw * or credentials have changed (the calling process dropped root 91 1.2.2.3 nathanw * root privilege). Check if root is the calling user. If it is, 92 1.2.2.3 nathanw * we try the system call, if it is not, we try clockctl. 93 1.2.2.2 nathanw */ 94 1.2.2.3 nathanw if (__clockctl_fd == -2) { 95 1.2.2.3 nathanw /* 96 1.2.2.3 nathanw * Root always uses the syscall 97 1.2.2.3 nathanw */ 98 1.2.2.3 nathanw if (geteuid() == 0) { 99 1.2.2.3 nathanw __clockctl_fd = -1; 100 1.2.2.3 nathanw goto try_syscall; 101 1.2.2.3 nathanw } 102 1.2.2.3 nathanw 103 1.2.2.3 nathanw /* 104 1.2.2.3 nathanw * If this fails, it means that we are not root 105 1.2.2.3 nathanw * and we cannot open clockctl. This is a failure. 106 1.2.2.3 nathanw */ 107 1.2.2.3 nathanw __clockctl_fd = open(_PATH_CLOCKCTL, O_WRONLY, 0); 108 1.2.2.3 nathanw if (__clockctl_fd == -1) 109 1.2.2.3 nathanw return -1; 110 1.2.2.3 nathanw } 111 1.2.2.2 nathanw 112 1.2.2.2 nathanw /* 113 1.2.2.3 nathanw * If __clockctl_fd >=0, clockctl has already been open 114 1.2.2.3 nathanw * and used, so we carry on using it. 115 1.2.2.2 nathanw */ 116 1.2.2.3 nathanw SCARG(&args, delta) = delta; 117 1.2.2.3 nathanw SCARG(&args, olddelta) = olddelta; 118 1.2.2.3 nathanw error = ioctl(__clockctl_fd, CLOCKCTL_ADJTIME, &args); 119 1.2.2.3 nathanw return error; 120 1.2.2.2 nathanw 121 1.2.2.2 nathanw } 122
Indexes created Wed Oct 01 19:09:53 GMT 2025