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 */
87static 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 */
95static 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 */
104static ulong_t  lasttime;
105static ulong_t  lastday;
106static ushort_t lastddate;
107static ushort_t lastdtime;
108
109/* Lock for the lastxxx variables */
110static kmutex_t lastdt_lock;
111
112/*
113 * Number of seconds between 1970 and 1601 year
114 * (134774 days)
115 */
116const uint64_t DIFF1970TO1601 = 11644473600ULL;
117const 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 */
125void
126smb_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 */
157void
158smb_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 */
178void
179smb_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
187void
188smb_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
201void
202smb_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
289static ushort_t lastdosdate;
290static ulong_t  lastseconds;
291
292void
293smb_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
343void
344smb_time_init(void)
345{
346	mutex_init(&lastdt_lock, NULL, MUTEX_DEFAULT, NULL);
347}
348
349void
350smb_time_fini(void)
351{
352	mutex_destroy(&lastdt_lock);
353}
354