xref: /illumos-gate/usr/src/uts/common/fs/smbclnt/netsmb/smb_time.c (revision 56f33205c9ed776c3c909e07d52e94610a675740)
1 /*
2  * Copyright (c) 2000-2001, Boris Popov
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *    This product includes software developed by Boris Popov.
16  * 4. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * $Id: smbfs_subr.c,v 1.18 2005/02/02 00:22:23 lindak Exp $
33  */
34 
35 /*
36  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
37  * Use is subject to license terms.
38  */
39 
40 /*
41  * Time conversion functions (to/from DOS, NT times)
42  * From BSD/Darwin smbfs_subr.c
43  */
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/time.h>
48 #include <sys/vnode.h>
49 #include <sys/sunddi.h>
50 
51 #include <netsmb/smb_osdep.h>
52 
53 #include <netsmb/smb.h>
54 #include <netsmb/smb_conn.h>
55 #include <netsmb/smb_subr.h>
56 
57 /*
58  * Time & date conversion routines taken from msdosfs. Although leap
59  * year calculation is bogus, it's sufficient before 2100 :)
60  */
61 /*
62  * This is the format of the contents of the deTime field in the direntry
63  * structure.
64  * We don't use bitfields because we don't know how compilers for
65  * arbitrary machines will lay them out.
66  */
67 #define	DT_2SECONDS_MASK	0x1F	/* seconds divided by 2 */
68 #define	DT_2SECONDS_SHIFT	0
69 #define	DT_MINUTES_MASK		0x7E0	/* minutes */
70 #define	DT_MINUTES_SHIFT	5
71 #define	DT_HOURS_MASK		0xF800	/* hours */
72 #define	DT_HOURS_SHIFT		11
73 
74 /*
75  * This is the format of the contents of the deDate field in the direntry
76  * structure.
77  */
78 #define	DD_DAY_MASK		0x1F	/* day of month */
79 #define	DD_DAY_SHIFT		0
80 #define	DD_MONTH_MASK		0x1E0	/* month */
81 #define	DD_MONTH_SHIFT		5
82 #define	DD_YEAR_MASK		0xFE00	/* year - 1980 */
83 #define	DD_YEAR_SHIFT		9
84 /*
85  * Total number of days that have passed for each month in a regular year.
86  */
87 static ushort_t regyear[] = {
88 	31, 59, 90, 120, 151, 181,
89 	212, 243, 273, 304, 334, 365
90 };
91 
92 /*
93  * Total number of days that have passed for each month in a leap year.
94  */
95 static ushort_t leapyear[] = {
96 	31, 60, 91, 121, 152, 182,
97 	213, 244, 274, 305, 335, 366
98 };
99 
100 /*
101  * Variables used to remember parts of the last time conversion.  Maybe we
102  * can avoid a full conversion.
103  */
104 static ulong_t  lasttime;
105 static ulong_t  lastday;
106 static ushort_t lastddate;
107 static ushort_t lastdtime;
108 
109 /* Lock for the lastxxx variables */
110 static kmutex_t lastdt_lock;
111 
112 /*
113  * Number of seconds between 1970 and 1601 year
114  * (134774 days)
115  */
116 const uint64_t DIFF1970TO1601 = 11644473600ULL;
117 const uint32_t TEN_MIL = 10000000UL;
118 
119 /*
120  * Convert NT time (tenths of microseconds since 1601)
121  * to Unix seconds+nanoseconds since 1970.  Any time
122  * earlier than 1970 is converted to Unix time zero.
123  * Both are GMT-based (no time zone adjustments).
124  */
125 void
126 smb_time_NT2local(uint64_t nt_time, struct timespec *tsp)
127 {
128 	uint64_t nt_sec;	/* seconds */
129 	uint64_t nt_tus;	/* tenths of uSec. */
130 
131 	/* Optimize time zero. */
132 	if (nt_time == 0) {
133 		tsp->tv_sec = 0;
134 		tsp->tv_nsec = 0;
135 		return;
136 	}
137 
138 	nt_sec = nt_time / TEN_MIL;
139 	nt_tus = nt_time % TEN_MIL;
140 
141 	if (nt_sec <= DIFF1970TO1601) {
142 		tsp->tv_sec = 0;
143 		tsp->tv_nsec = 0;
144 		return;
145 	}
146 	tsp->tv_sec = nt_sec - DIFF1970TO1601;
147 	tsp->tv_nsec = nt_tus * 100;
148 }
149 
150 /*
151  * Convert Unix time (seconds+nanoseconds since 1970)
152  * to NT time (tenths of microseconds since 1601).
153  * Exception: Convert time zero (really any time in
154  * the first second of 1970) to NT time zero.
155  * Both are GMT-based (no time zone adjustments).
156  */
157 void
158 smb_time_local2NT(struct timespec *tsp, uint64_t *nt_time)
159 {
160 	uint64_t nt_sec;	/* seconds */
161 	uint64_t nt_tus;	/* tenths of uSec. */
162 
163 	if (tsp->tv_sec == 0) {
164 		*nt_time = 0;
165 		return;
166 	}
167 
168 	nt_sec = tsp->tv_sec + DIFF1970TO1601;
169 	nt_tus = tsp->tv_nsec / 100;
170 
171 	*nt_time = (uint64_t)nt_sec * TEN_MIL + nt_tus;
172 }
173 
174 /*
175  * Time zone conversion stuff, only used in old dialects.
176  * Don't adjust time zero for either conversion.
177  */
178 void
179 smb_time_local2server(struct timespec *tsp, int tzoff, long *seconds)
180 {
181 	if (tsp->tv_sec <= (tzoff * 60))
182 		*seconds = 0;
183 	else
184 		*seconds = tsp->tv_sec - (tzoff * 60);
185 }
186 
187 void
188 smb_time_server2local(ulong_t seconds, int tzoff, struct timespec *tsp)
189 {
190 	if (seconds == 0)
191 		tsp->tv_sec = 0;
192 	else
193 		tsp->tv_sec = seconds + tzoff * 60;
194 	tsp->tv_nsec = 0;
195 }
196 
197 /*
198  * Time conversions to/from DOS format, for old dialects.
199  */
200 
201 void
202 smb_time_unix2dos(struct timespec *tsp, int tzoff, u_int16_t *ddp,
203 	u_int16_t *dtp,	u_int8_t *dhp)
204 {
205 	long t;
206 	ulong_t days, year, month, inc;
207 	ushort_t *months;
208 
209 	mutex_enter(&lastdt_lock);
210 
211 	/*
212 	 * If the time from the last conversion is the same as now, then
213 	 * skip the computations and use the saved result.
214 	 */
215 	smb_time_local2server(tsp, tzoff, &t);
216 	t &= ~1;
217 	if (lasttime != t) {
218 		lasttime = t;
219 		if (t < 0) {
220 			/*
221 			 * This is before 1970, so it's before 1980,
222 			 * and can't be represented as a DOS time.
223 			 * Just represent it as the DOS epoch.
224 			 */
225 			lastdtime = 0;
226 			lastddate = (1 << DD_DAY_SHIFT)
227 			    + (1 << DD_MONTH_SHIFT)
228 			    + ((1980 - 1980) << DD_YEAR_SHIFT);
229 		} else {
230 			lastdtime = (((t / 2) % 30) << DT_2SECONDS_SHIFT)
231 			    + (((t / 60) % 60) << DT_MINUTES_SHIFT)
232 			    + (((t / 3600) % 24) << DT_HOURS_SHIFT);
233 
234 			/*
235 			 * If the number of days since 1970 is the same as
236 			 * the last time we did the computation then skip
237 			 * all this leap year and month stuff.
238 			 */
239 			days = t / (24 * 60 * 60);
240 			if (days != lastday) {
241 				lastday = days;
242 				for (year = 1970; ; year++) {
243 					/*
244 					 * XXX - works in 2000, but won't
245 					 * work in 2100.
246 					 */
247 					inc = year & 0x03 ? 365 : 366;
248 					if (days < inc)
249 						break;
250 					days -= inc;
251 				}
252 				/*
253 				 * XXX - works in 2000, but won't work in 2100.
254 				 */
255 				months = year & 0x03 ? regyear : leapyear;
256 				for (month = 0; days >= months[month]; month++)
257 					;
258 				if (month > 0)
259 					days -= months[month - 1];
260 				lastddate = ((days + 1) << DD_DAY_SHIFT)
261 				    + ((month + 1) << DD_MONTH_SHIFT);
262 				/*
263 				 * Remember DOS's idea of time is relative
264 				 * to 1980, but UN*X's is relative to 1970.
265 				 * If somehow we get a time before 1980 then
266 				 * don't give totally crazy results.
267 				 */
268 				if (year > 1980)
269 					lastddate += (year - 1980) <<
270 					    DD_YEAR_SHIFT;
271 			}
272 		}
273 	}
274 	if (dhp)
275 		*dhp = (tsp->tv_sec & 1) * 100 + tsp->tv_nsec / 10000000;
276 
277 	*ddp = lastddate;
278 	*dtp = lastdtime;
279 
280 	mutex_exit(&lastdt_lock);
281 }
282 
283 /*
284  * The number of seconds between Jan 1, 1970 and Jan 1, 1980. In that
285  * interval there were 8 regular years and 2 leap years.
286  */
287 #define	SECONDSTO1980	(((8 * 365) + (2 * 366)) * (24 * 60 * 60))
288 
289 static ushort_t lastdosdate;
290 static ulong_t  lastseconds;
291 
292 void
293 smb_dos2unixtime(uint_t dd, uint_t dt, uint_t dh, int tzoff,
294 	struct timespec *tsp)
295 {
296 	ulong_t seconds;
297 	ulong_t month;
298 	ulong_t year;
299 	ulong_t days;
300 	ushort_t *months;
301 
302 	if (dd == 0) {
303 		tsp->tv_sec = 0;
304 		tsp->tv_nsec = 0;
305 		return;
306 	}
307 	seconds = (((dt & DT_2SECONDS_MASK) >> DT_2SECONDS_SHIFT) << 1)
308 	    + ((dt & DT_MINUTES_MASK) >> DT_MINUTES_SHIFT) * 60
309 	    + ((dt & DT_HOURS_MASK) >> DT_HOURS_SHIFT) * 3600
310 	    + dh / 100;
311 
312 	/*
313 	 * If the year, month, and day from the last conversion are the
314 	 * same then use the saved value.
315 	 */
316 	mutex_enter(&lastdt_lock);
317 	if (lastdosdate != dd) {
318 		lastdosdate = (ushort_t)dd;
319 		days = 0;
320 		year = (dd & DD_YEAR_MASK) >> DD_YEAR_SHIFT;
321 		days = year * 365;
322 		days += year / 4 + 1;	/* add in leap days */
323 		/*
324 		 * XXX - works in 2000, but won't work in 2100.
325 		 */
326 		if ((year & 0x03) == 0)
327 			days--;		/* if year is a leap year */
328 		months = year & 0x03 ? regyear : leapyear;
329 		month = (dd & DD_MONTH_MASK) >> DD_MONTH_SHIFT;
330 		if (month < 1 || month > 12) {
331 			month = 1;
332 		}
333 		if (month > 1)
334 			days += months[month - 2];
335 		days += ((dd & DD_DAY_MASK) >> DD_DAY_SHIFT) - 1;
336 		lastseconds = (days * 24 * 60 * 60) + SECONDSTO1980;
337 	}
338 	smb_time_server2local(seconds + lastseconds, tzoff, tsp);
339 	tsp->tv_nsec = (dh % 100) * 10000000;
340 	mutex_exit(&lastdt_lock);
341 }
342 
343 void
344 smb_time_init(void)
345 {
346 	mutex_init(&lastdt_lock, NULL, MUTEX_DEFAULT, NULL);
347 }
348 
349 void
350 smb_time_fini(void)
351 {
352 	mutex_destroy(&lastdt_lock);
353 }
354