1 /*
2  * SPDX-License-Identifier: ISC
3  *
4  * Copyright (c) 2014-2018 Todd C. Miller <Todd.Miller@sudo.ws>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 /*
20  * This is an open source non-commercial project. Dear PVS-Studio, please check it.
21  * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
22  */
23 
24 #include <config.h>
25 
26 #include <sys/time.h>
27 #include <time.h>
28 
29 #if defined(__MACH__) && !defined(HAVE_CLOCK_GETTIME)
30 # include <mach/mach.h>
31 # include <mach/mach_time.h>
32 # include <mach/clock.h>
33 #endif
34 
35 #include "sudo_compat.h"
36 #include "sudo_debug.h"
37 #include "sudo_util.h"
38 
39 /*
40  * On Linux and FreeBSD, CLOCK_MONOTONIC does not run while sleeping.
41  * Linux provides CLOCK_BOOTTIME which runs while sleeping (FreeBSD does not).
42  * Some systems provide CLOCK_UPTIME which only runs while awake.
43  */
44 #if defined(CLOCK_BOOTTIME)
45 # define SUDO_CLOCK_BOOTTIME	CLOCK_BOOTTIME
46 #elif defined(CLOCK_MONOTONIC_RAW)
47 # define SUDO_CLOCK_BOOTTIME	CLOCK_MONOTONIC_RAW
48 #elif defined(CLOCK_MONOTONIC)
49 # define SUDO_CLOCK_BOOTTIME	CLOCK_MONOTONIC
50 #endif
51 #if defined(CLOCK_UPTIME_RAW)
52 # define SUDO_CLOCK_UPTIME	CLOCK_UPTIME_RAW
53 #elif defined(CLOCK_UPTIME)
54 # define SUDO_CLOCK_UPTIME	CLOCK_UPTIME
55 #elif defined(CLOCK_MONOTONIC)
56 # define SUDO_CLOCK_UPTIME	CLOCK_MONOTONIC
57 #endif
58 
59 /*
60  * Wall clock time, may run backward.
61  */
62 #if defined(HAVE_CLOCK_GETTIME)
63 int
sudo_gettime_real_v1(struct timespec * ts)64 sudo_gettime_real_v1(struct timespec *ts)
65 {
66     debug_decl(sudo_gettime_real, SUDO_DEBUG_UTIL);
67 
68     if (clock_gettime(CLOCK_REALTIME, ts) == -1) {
69 	struct timeval tv;
70 
71 	sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_ERRNO|SUDO_DEBUG_LINENO,
72 	    "clock_gettime(CLOCK_REALTIME) failed, trying gettimeofday()");
73 	if (gettimeofday(&tv, NULL) == -1)
74 	    debug_return_int(-1);
75 	TIMEVAL_TO_TIMESPEC(&tv, ts);
76     }
77     debug_return_int(0);
78 }
79 #else
80 int
sudo_gettime_real_v1(struct timespec * ts)81 sudo_gettime_real_v1(struct timespec *ts)
82 {
83     struct timeval tv;
84     debug_decl(sudo_gettime_real, SUDO_DEBUG_UTIL);
85 
86     if (gettimeofday(&tv, NULL) == -1)
87 	debug_return_int(-1);
88     TIMEVAL_TO_TIMESPEC(&tv, ts);
89     debug_return_int(0);
90 }
91 #endif
92 
93 /*
94  * Monotonic time, only runs forward.
95  * We use a timer that only increments while sleeping, if possible.
96  */
97 #if defined(HAVE_CLOCK_GETTIME) && defined(SUDO_CLOCK_BOOTTIME)
98 int
sudo_gettime_mono_v1(struct timespec * ts)99 sudo_gettime_mono_v1(struct timespec *ts)
100 {
101     static int has_monoclock = -1;
102     debug_decl(sudo_gettime_mono, SUDO_DEBUG_UTIL);
103 
104     /* Check whether the kernel/libc actually supports a monotonic clock. */
105 # ifdef _SC_MONOTONIC_CLOCK
106     if (has_monoclock == -1)
107 	has_monoclock = sysconf(_SC_MONOTONIC_CLOCK) != -1;
108 # endif
109     if (!has_monoclock)
110 	debug_return_int(sudo_gettime_real(ts));
111     if (clock_gettime(SUDO_CLOCK_BOOTTIME, ts) == -1) {
112 	sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_ERRNO|SUDO_DEBUG_LINENO,
113 	    "clock_gettime(%d) failed, using wall clock",
114 	    (int)SUDO_CLOCK_BOOTTIME);
115 	has_monoclock = 0;
116 	debug_return_int(sudo_gettime_real(ts));
117     }
118     debug_return_int(0);
119 }
120 #elif defined(HAVE_GETHRTIME)
121 int
sudo_gettime_mono_v1(struct timespec * ts)122 sudo_gettime_mono_v1(struct timespec *ts)
123 {
124     hrtime_t nsec;
125     debug_decl(sudo_gettime_mono, SUDO_DEBUG_UTIL);
126 
127     nsec = gethrtime();
128     ts->tv_sec = nsec / 1000000000;
129     ts->tv_nsec = nsec % 1000000000;
130     debug_return_int(0);
131 }
132 #elif defined(__MACH__)
133 int
sudo_gettime_mono_v1(struct timespec * ts)134 sudo_gettime_mono_v1(struct timespec *ts)
135 {
136     uint64_t abstime, nsec;
137     static mach_timebase_info_data_t timebase_info;
138     debug_decl(sudo_gettime_mono, SUDO_DEBUG_UTIL);
139 
140     if (timebase_info.denom == 0)
141 	(void) mach_timebase_info(&timebase_info);
142 #ifdef HAVE_MACH_CONTINUOUS_TIME
143     abstime = mach_continuous_time();		/* runs while asleep */
144 #else
145     abstime = mach_absolute_time();		/* doesn't run while asleep */
146 #endif
147     nsec = abstime * timebase_info.numer / timebase_info.denom;
148     ts->tv_sec = nsec / 1000000000;
149     ts->tv_nsec = nsec % 1000000000;
150     debug_return_int(0);
151 }
152 #else
153 int
sudo_gettime_mono_v1(struct timespec * ts)154 sudo_gettime_mono_v1(struct timespec *ts)
155 {
156     /* No monotonic clock available, use wall clock. */
157     return sudo_gettime_real(ts);
158 }
159 #endif
160 
161 /*
162  * Monotonic time, only runs forward.
163  * We use a timer that only increments while awake, if possible.
164  */
165 #if defined(HAVE_CLOCK_GETTIME) && defined(SUDO_CLOCK_UPTIME)
166 int
sudo_gettime_awake_v1(struct timespec * ts)167 sudo_gettime_awake_v1(struct timespec *ts)
168 {
169     static int has_monoclock = -1;
170     debug_decl(sudo_gettime_awake, SUDO_DEBUG_UTIL);
171 
172     /* Check whether the kernel/libc actually supports a monotonic clock. */
173 # ifdef _SC_MONOTONIC_CLOCK
174     if (has_monoclock == -1)
175 	has_monoclock = sysconf(_SC_MONOTONIC_CLOCK) != -1;
176 # endif
177     if (!has_monoclock)
178 	debug_return_int(sudo_gettime_real(ts));
179     if (clock_gettime(SUDO_CLOCK_UPTIME, ts) == -1) {
180 	sudo_debug_printf(SUDO_DEBUG_WARN|SUDO_DEBUG_ERRNO|SUDO_DEBUG_LINENO,
181 	    "clock_gettime(%d) failed, using wall clock",
182 	    (int)SUDO_CLOCK_UPTIME);
183 	has_monoclock = 0;
184 	debug_return_int(sudo_gettime_real(ts));
185     }
186     debug_return_int(0);
187 }
188 #elif defined(HAVE_GETHRTIME)
189 int
sudo_gettime_awake_v1(struct timespec * ts)190 sudo_gettime_awake_v1(struct timespec *ts)
191 {
192     hrtime_t nsec;
193     debug_decl(sudo_gettime_awake, SUDO_DEBUG_UTIL);
194 
195     /* Currently the same as sudo_gettime_mono() */
196     nsec = gethrtime();
197     ts->tv_sec = nsec / 1000000000;
198     ts->tv_nsec = nsec % 1000000000;
199     debug_return_int(0);
200 }
201 #elif defined(__MACH__)
202 int
sudo_gettime_awake_v1(struct timespec * ts)203 sudo_gettime_awake_v1(struct timespec *ts)
204 {
205     uint64_t abstime, nsec;
206     static mach_timebase_info_data_t timebase_info;
207     debug_decl(sudo_gettime_awake, SUDO_DEBUG_UTIL);
208 
209     if (timebase_info.denom == 0)
210 	(void) mach_timebase_info(&timebase_info);
211     abstime = mach_absolute_time();
212     nsec = abstime * timebase_info.numer / timebase_info.denom;
213     ts->tv_sec = nsec / 1000000000;
214     ts->tv_nsec = nsec % 1000000000;
215     debug_return_int(0);
216 }
217 #else
218 int
sudo_gettime_awake_v1(struct timespec * ts)219 sudo_gettime_awake_v1(struct timespec *ts)
220 {
221     /* No monotonic uptime clock available, use wall clock. */
222     return sudo_gettime_real(ts);
223 }
224 #endif
225