1 /*
2 * Copyright (c) 1999, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 #include <windows.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include "jvm.h"
30 #include "TimeZone_md.h"
31
32 #define VALUE_UNKNOWN 0
33 #define VALUE_KEY 1
34 #define VALUE_MAPID 2
35 #define VALUE_GMTOFFSET 3
36
37 #define MAX_ZONE_CHAR 256
38 #define MAX_MAPID_LENGTH 32
39
40 #define NT_TZ_KEY "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Time Zones"
41 #define WIN_TZ_KEY "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Time Zones"
42 #define WIN_CURRENT_TZ_KEY "System\\CurrentControlSet\\Control\\TimeZoneInformation"
43
44 typedef struct _TziValue {
45 LONG bias;
46 LONG stdBias;
47 LONG dstBias;
48 SYSTEMTIME stdDate;
49 SYSTEMTIME dstDate;
50 } TziValue;
51
52 /*
53 * Registry key names
54 */
55 static void *keyNames[] = {
56 (void *) L"StandardName",
57 (void *) "StandardName",
58 (void *) L"Std",
59 (void *) "Std"
60 };
61
62 /*
63 * Indices to keyNames[]
64 */
65 #define STANDARD_NAME 0
66 #define STD_NAME 2
67
68 /*
69 * Calls RegQueryValueEx() to get the value for the specified key. If
70 * the platform is NT, 2000 or XP, it calls the Unicode
71 * version. Otherwise, it calls the ANSI version and converts the
72 * value to Unicode. In this case, it assumes that the current ANSI
73 * Code Page is the same as the native platform code page (e.g., Code
74 * Page 932 for the Japanese Windows systems.
75 *
76 * `keyIndex' is an index value to the keyNames in Unicode
77 * (WCHAR). `keyIndex' + 1 points to its ANSI value.
78 *
79 * Returns the status value. ERROR_SUCCESS if succeeded, a
80 * non-ERROR_SUCCESS value otherwise.
81 */
82 static LONG
83 getValueInRegistry(HKEY hKey,
84 int keyIndex,
85 LPDWORD typePtr,
86 LPBYTE buf,
87 LPDWORD bufLengthPtr)
88 {
89 LONG ret;
90 DWORD bufLength = *bufLengthPtr;
91 char val[MAX_ZONE_CHAR];
92 DWORD valSize;
93 int len;
94
95 *typePtr = 0;
96 ret = RegQueryValueExW(hKey, (WCHAR *) keyNames[keyIndex], NULL,
97 typePtr, buf, bufLengthPtr);
98 if (ret == ERROR_SUCCESS && *typePtr == REG_SZ) {
99 return ret;
100 }
101
102 valSize = sizeof(val);
103 ret = RegQueryValueExA(hKey, (char *) keyNames[keyIndex + 1], NULL,
104 typePtr, val, &valSize);
105 if (ret != ERROR_SUCCESS) {
106 return ret;
107 }
108 if (*typePtr != REG_SZ) {
109 return ERROR_BADKEY;
110 }
111
112 len = MultiByteToWideChar(CP_ACP, MB_ERR_INVALID_CHARS,
113 (LPCSTR) val, -1,
114 (LPWSTR) buf, bufLength/sizeof(WCHAR));
115 if (len <= 0) {
116 return ERROR_BADKEY;
117 }
118 return ERROR_SUCCESS;
119 }
120
121 /*
122 * Produces custom name "GMT+hh:mm" from the given bias in buffer.
123 */
124 static void customZoneName(LONG bias, char *buffer) {
125 LONG gmtOffset;
126 int sign;
127
128 if (bias > 0) {
129 gmtOffset = bias;
130 sign = -1;
131 } else {
132 gmtOffset = -bias;
133 sign = 1;
134 }
135 if (gmtOffset != 0) {
136 sprintf(buffer, "GMT%c%02d:%02d",
137 ((sign >= 0) ? '+' : '-'),
138 gmtOffset / 60,
139 gmtOffset % 60);
140 } else {
141 strcpy(buffer, "GMT");
142 }
143 }
144
145 /*
146 * Gets the current time zone entry in the "Time Zones" registry.
147 */
148 static int getWinTimeZone(char *winZoneName, char *winMapID)
149 {
150 DYNAMIC_TIME_ZONE_INFORMATION dtzi;
151 DWORD timeType;
152 DWORD bufSize;
153 DWORD val;
154 HANDLE hKey = NULL;
155 LONG ret;
156 ULONG valueType;
157
158 /*
159 * Get the dynamic time zone information so that time zone redirection
160 * can be supported. (see JDK-7044727)
161 */
162 timeType = GetDynamicTimeZoneInformation(&dtzi);
163 if (timeType == TIME_ZONE_ID_INVALID) {
164 goto err;
165 }
166
167 /*
168 * Make sure TimeZoneKeyName is available from the API call. If
169 * DynamicDaylightTime is disabled, return a custom time zone name
170 * based on the GMT offset. Otherwise, return the TimeZoneKeyName
171 * value.
172 */
173 if (dtzi.TimeZoneKeyName[0] != 0) {
174 if (dtzi.DynamicDaylightTimeDisabled) {
175 customZoneName(dtzi.Bias, winZoneName);
176 return VALUE_GMTOFFSET;
177 }
178 wcstombs(winZoneName, dtzi.TimeZoneKeyName, MAX_ZONE_CHAR);
179 return VALUE_KEY;
180 }
181
182 /*
183 * If TimeZoneKeyName is not available, check whether StandardName
184 * is available to fall back to the older API GetTimeZoneInformation.
185 * If not, directly read the value from registry keys.
186 */
187 if (dtzi.StandardName[0] == 0) {
188 ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_CURRENT_TZ_KEY, 0,
189 KEY_READ, (PHKEY)&hKey);
190 if (ret != ERROR_SUCCESS) {
191 goto err;
192 }
193
194 /*
195 * Determine if auto-daylight time adjustment is turned off.
196 */
197 bufSize = sizeof(val);
198 ret = RegQueryValueExA(hKey, "DynamicDaylightTimeDisabled", NULL,
199 &valueType, (LPBYTE) &val, &bufSize);
200 if (ret != ERROR_SUCCESS) {
201 goto err;
202 }
203 /*
204 * Return a custom time zone name if auto-daylight time adjustment
205 * is disabled.
206 */
207 if (val == 1) {
208 customZoneName(dtzi.Bias, winZoneName);
209 (void) RegCloseKey(hKey);
210 return VALUE_GMTOFFSET;
211 }
212
213 bufSize = MAX_ZONE_CHAR;
214 ret = RegQueryValueExA(hKey, "TimeZoneKeyName", NULL,
215 &valueType, (LPBYTE) winZoneName, &bufSize);
216 if (ret != ERROR_SUCCESS) {
217 goto err;
218 }
219 (void) RegCloseKey(hKey);
220 return VALUE_KEY;
221 } else {
222 /*
223 * Fall back to GetTimeZoneInformation
224 */
225 TIME_ZONE_INFORMATION tzi;
226 HANDLE hSubKey = NULL;
227 DWORD nSubKeys, i;
228 ULONG valueType;
229 TCHAR subKeyName[MAX_ZONE_CHAR];
230 TCHAR szValue[MAX_ZONE_CHAR];
231 WCHAR stdNameInReg[MAX_ZONE_CHAR];
232 TziValue tempTzi;
233 WCHAR *stdNamePtr = tzi.StandardName;
234 DWORD valueSize;
235 int onlyMapID;
236
237 timeType = GetTimeZoneInformation(&tzi);
238 if (timeType == TIME_ZONE_ID_INVALID) {
239 goto err;
240 }
241
242 ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_CURRENT_TZ_KEY, 0,
243 KEY_READ, (PHKEY)&hKey);
244 if (ret == ERROR_SUCCESS) {
245 /*
246 * Determine if auto-daylight time adjustment is turned off.
247 */
248 bufSize = sizeof(val);
249 ret = RegQueryValueExA(hKey, "DynamicDaylightTimeDisabled", NULL,
250 &valueType, (LPBYTE) &val, &bufSize);
251 if (ret == ERROR_SUCCESS) {
252 if (val == 1 && tzi.DaylightDate.wMonth != 0) {
253 (void) RegCloseKey(hKey);
254 customZoneName(tzi.Bias, winZoneName);
255 return VALUE_GMTOFFSET;
256 }
257 }
258
259 /*
260 * Win32 problem: If the length of the standard time name is equal
261 * to (or probably longer than) 32 in the registry,
262 * GetTimeZoneInformation() on NT returns a null string as its
263 * standard time name. We need to work around this problem by
264 * getting the same information from the TimeZoneInformation
265 * registry.
266 */
267 if (tzi.StandardName[0] == 0) {
268 bufSize = sizeof(stdNameInReg);
269 ret = getValueInRegistry(hKey, STANDARD_NAME, &valueType,
270 (LPBYTE) stdNameInReg, &bufSize);
271 if (ret != ERROR_SUCCESS) {
272 goto err;
273 }
274 stdNamePtr = stdNameInReg;
275 }
276 (void) RegCloseKey(hKey);
277 }
278
279 /*
280 * Open the "Time Zones" registry.
281 */
282 ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE, NT_TZ_KEY, 0, KEY_READ, (PHKEY)&hKey);
283 if (ret != ERROR_SUCCESS) {
284 ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_TZ_KEY, 0, KEY_READ, (PHKEY)&hKey);
285 /*
286 * If both failed, then give up.
287 */
288 if (ret != ERROR_SUCCESS) {
289 return VALUE_UNKNOWN;
290 }
291 }
292
293 /*
294 * Get the number of subkeys of the "Time Zones" registry for
295 * enumeration.
296 */
297 ret = RegQueryInfoKey(hKey, NULL, NULL, NULL, &nSubKeys,
298 NULL, NULL, NULL, NULL, NULL, NULL, NULL);
299 if (ret != ERROR_SUCCESS) {
300 goto err;
301 }
302
303 /*
304 * Compare to the "Std" value of each subkey and find the entry that
305 * matches the current control panel setting.
306 */
307 onlyMapID = 0;
308 for (i = 0; i < nSubKeys; ++i) {
309 DWORD size = sizeof(subKeyName);
310 ret = RegEnumKeyEx(hKey, i, subKeyName, &size, NULL, NULL, NULL, NULL);
311 if (ret != ERROR_SUCCESS) {
312 goto err;
313 }
314 ret = RegOpenKeyEx(hKey, subKeyName, 0, KEY_READ, (PHKEY)&hSubKey);
315 if (ret != ERROR_SUCCESS) {
316 goto err;
317 }
318
319 size = sizeof(szValue);
320 ret = getValueInRegistry(hSubKey, STD_NAME, &valueType,
321 szValue, &size);
322 if (ret != ERROR_SUCCESS) {
323 /*
324 * NT 4.0 SP3 fails here since it doesn't have the "Std"
325 * entry in the Time Zones registry.
326 */
327 RegCloseKey(hSubKey);
328 onlyMapID = 1;
329 ret = RegOpenKeyExW(hKey, stdNamePtr, 0, KEY_READ, (PHKEY)&hSubKey);
330 if (ret != ERROR_SUCCESS) {
331 goto err;
332 }
333 break;
334 }
335
336 if (wcscmp((WCHAR *)szValue, stdNamePtr) == 0) {
337 /*
338 * Some localized Win32 platforms use a same name to
339 * different time zones. So, we can't rely only on the name
340 * here. We need to check GMT offsets and transition dates
341 * to make sure it's the registry of the current time
342 * zone.
343 */
344 DWORD tziValueSize = sizeof(tempTzi);
345 ret = RegQueryValueEx(hSubKey, "TZI", NULL, &valueType,
346 (unsigned char *) &tempTzi, &tziValueSize);
347 if (ret == ERROR_SUCCESS) {
348 if ((tzi.Bias != tempTzi.bias) ||
349 (memcmp((const void *) &tzi.StandardDate,
350 (const void *) &tempTzi.stdDate,
351 sizeof(SYSTEMTIME)) != 0)) {
352 goto out;
353 }
354
355 if (tzi.DaylightBias != 0) {
356 if ((tzi.DaylightBias != tempTzi.dstBias) ||
357 (memcmp((const void *) &tzi.DaylightDate,
358 (const void *) &tempTzi.dstDate,
359 sizeof(SYSTEMTIME)) != 0)) {
360 goto out;
361 }
362 }
363 }
364
365 /*
366 * found matched record, terminate search
367 */
368 strcpy(winZoneName, subKeyName);
369 break;
370 }
371 out:
372 (void) RegCloseKey(hSubKey);
373 }
374
375 /*
376 * Get the "MapID" value of the registry to be able to eliminate
377 * duplicated key names later.
378 */
379 valueSize = MAX_MAPID_LENGTH;
380 ret = RegQueryValueExA(hSubKey, "MapID", NULL, &valueType, winMapID, &valueSize);
381 (void) RegCloseKey(hSubKey);
382 (void) RegCloseKey(hKey);
383
384 if (ret != ERROR_SUCCESS) {
385 /*
386 * Vista doesn't have mapID. VALUE_UNKNOWN should be returned
387 * only for Windows NT.
388 */
389 if (onlyMapID == 1) {
390 return VALUE_UNKNOWN;
391 }
392 }
393 }
394
395 return VALUE_KEY;
396
397 err:
398 if (hKey != NULL) {
399 (void) RegCloseKey(hKey);
400 }
401 return VALUE_UNKNOWN;
402 }
403
404 /*
405 * The mapping table file name.
406 */
407 #define MAPPINGS_FILE "\\lib\\tzmappings"
408
409 /*
410 * Index values for the mapping table.
411 */
412 #define TZ_WIN_NAME 0
413 #define TZ_MAPID 1
414 #define TZ_REGION 2
415 #define TZ_JAVA_NAME 3
416
417 #define TZ_NITEMS 4 /* number of items (fields) */
418
419 /*
420 * Looks up the mapping table (tzmappings) and returns a Java time
421 * zone ID (e.g., "America/Los_Angeles") if found. Otherwise, NULL is
422 * returned.
423 *
424 * value_type is one of the following values:
425 * VALUE_KEY for exact key matching
426 * VALUE_MAPID for MapID (this is
427 * required for the old Windows, such as NT 4.0 SP3).
428 */
429 static char *matchJavaTZ(const char *java_home_dir, int value_type, char *tzName,
430 char *mapID)
431 {
432 int line;
433 int IDmatched = 0;
434 FILE *fp;
435 char *javaTZName = NULL;
436 char *items[TZ_NITEMS];
437 char *mapFileName;
438 char lineBuffer[MAX_ZONE_CHAR * 4];
439 int noMapID = *mapID == '\0'; /* no mapID on Vista and later */
440 int offset = 0;
441 const char* errorMessage = "unknown error";
442
443 mapFileName = malloc(strlen(java_home_dir) + strlen(MAPPINGS_FILE) + 1);
444 if (mapFileName == NULL) {
445 return NULL;
446 }
447 strcpy(mapFileName, java_home_dir);
448 strcat(mapFileName, MAPPINGS_FILE);
449
450 if ((fp = fopen(mapFileName, "r")) == NULL) {
451 jio_fprintf(stderr, "can't open %s.\n", mapFileName);
452 free((void *) mapFileName);
453 return NULL;
454 }
455 free((void *) mapFileName);
456
457 line = 0;
458 while (fgets(lineBuffer, sizeof(lineBuffer), fp) != NULL) {
459 char *start, *idx, *endp;
460 int itemIndex = 0;
461
462 line++;
463 start = idx = lineBuffer;
464 endp = &lineBuffer[sizeof(lineBuffer)];
465
466 /*
467 * Ignore comment and blank lines.
468 */
469 if (*idx == '#' || *idx == '\n') {
470 continue;
471 }
472
473 for (itemIndex = 0; itemIndex < TZ_NITEMS; itemIndex++) {
474 items[itemIndex] = start;
475 while (*idx && *idx != ':') {
476 if (++idx >= endp) {
477 errorMessage = "premature end of line";
478 offset = (int)(idx - lineBuffer);
479 goto illegal_format;
480 }
481 }
482 if (*idx == '\0') {
483 errorMessage = "illegal character \0 found";
484 offset = (int)(idx - lineBuffer);
485 goto illegal_format;
486 }
487 *idx++ = '\0';
488 start = idx;
489 }
490
491 if (*idx != '\n') {
492 errorMessage = "illegal non-newline character found";
493 offset = (int)(idx - lineBuffer);
494 goto illegal_format;
495 }
496
497 if (noMapID || strcmp(mapID, items[TZ_MAPID]) == 0) {
498 /*
499 * When there's no mapID, we need to scan items until the
500 * exact match is found or the end of data is detected.
501 */
502 if (!noMapID) {
503 IDmatched = 1;
504 }
505 if (strcmp(items[TZ_WIN_NAME], tzName) == 0) {
506 /*
507 * Found the time zone in the mapping table.
508 */
509 javaTZName = _strdup(items[TZ_JAVA_NAME]);
510 break;
511 }
512 } else {
513 if (IDmatched == 1) {
514 /*
515 * No need to look up the mapping table further.
516 */
517 break;
518 }
519 }
520 }
521 fclose(fp);
522
523 return javaTZName;
524
525 illegal_format:
526 (void) fclose(fp);
527 jio_fprintf(stderr, "tzmappings: Illegal format at line %d (%s at offset %d, file: %s).\n",
528 line, message, offset, mapFileName);
529 return NULL;
530 }
531
532 /*
533 * Detects the platform time zone which maps to a Java time zone ID.
534 */
535 char *findJavaTZ_md(const char *java_home_dir)
536 {
537 char winZoneName[MAX_ZONE_CHAR];
538 char winMapID[MAX_MAPID_LENGTH];
539 char *std_timezone = NULL;
540 int result;
541
542 winMapID[0] = 0;
543 result = getWinTimeZone(winZoneName, winMapID);
544
545 if (result != VALUE_UNKNOWN) {
546 if (result == VALUE_GMTOFFSET) {
547 std_timezone = _strdup(winZoneName);
548 } else {
549 std_timezone = matchJavaTZ(java_home_dir, result,
550 winZoneName, winMapID);
551 if (std_timezone == NULL) {
552 std_timezone = getGMTOffsetID();
553 }
554 }
555 }
556 return std_timezone;
557 }
558
559 /**
560 * Returns a GMT-offset-based time zone ID.
561 */
562 char *
563 getGMTOffsetID()
564 {
565 LONG bias = 0;
566 LONG ret;
567 HANDLE hKey = NULL;
568 char zonename[32];
569
570 // Obtain the current GMT offset value of ActiveTimeBias.
571 ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_CURRENT_TZ_KEY, 0,
572 KEY_READ, (PHKEY)&hKey);
573 if (ret == ERROR_SUCCESS) {
574 DWORD val;
575 DWORD bufSize = sizeof(val);
576 ULONG valueType = 0;
577 ret = RegQueryValueExA(hKey, "ActiveTimeBias",
578 NULL, &valueType, (LPBYTE) &val, &bufSize);
579 if (ret == ERROR_SUCCESS) {
580 bias = (LONG) val;
581 }
582 (void) RegCloseKey(hKey);
583 }
584
585 // If we can't get the ActiveTimeBias value, use Bias of TimeZoneInformation.
586 // Note: Bias doesn't reflect current daylight saving.
587 if (ret != ERROR_SUCCESS) {
588 TIME_ZONE_INFORMATION tzi;
589 if (GetTimeZoneInformation(&tzi) != TIME_ZONE_ID_INVALID) {
590 bias = tzi.Bias;
591 }
592 }
593
594 customZoneName(bias, zonename);
595 return _strdup(zonename);
596 }