1 /*
2 * Copyright (c) 2013, 2020, 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 package java.util.zip;
27
28 import java.nio.ByteBuffer;
29 import java.nio.file.attribute.FileTime;
30 import java.time.DateTimeException;
31 import java.time.Instant;
32 import java.time.LocalDateTime;
33 import java.time.ZoneId;
34 import java.util.Date;
35 import java.util.concurrent.TimeUnit;
36
37 import static java.util.zip.ZipConstants.ENDHDR;
38
39 import jdk.internal.misc.Unsafe;
40
41 class ZipUtils {
42
43 // used to adjust values between Windows and java epoch
44 private static final long WINDOWS_EPOCH_IN_MICROSECONDS = -11644473600000000L;
45
46 // used to indicate the corresponding windows time is not available
47 public static final long WINDOWS_TIME_NOT_AVAILABLE = Long.MIN_VALUE;
48
49 // static final ByteBuffer defaultBuf = ByteBuffer.allocateDirect(0);
50 static final ByteBuffer defaultBuf = ByteBuffer.allocate(0);
51
52 /**
53 * Converts Windows time (in microseconds, UTC/GMT) time to FileTime.
54 */
55 public static final FileTime winTimeToFileTime(long wtime) {
56 return FileTime.from(wtime / 10 + WINDOWS_EPOCH_IN_MICROSECONDS,
57 TimeUnit.MICROSECONDS);
58 }
59
60 /**
61 * Converts FileTime to Windows time.
62 */
63 public static final long fileTimeToWinTime(FileTime ftime) {
64 return (ftime.to(TimeUnit.MICROSECONDS) - WINDOWS_EPOCH_IN_MICROSECONDS) * 10;
65 }
66
67 /**
68 * The upper bound of the 32-bit unix time, the "year 2038 problem".
69 */
70 public static final long UPPER_UNIXTIME_BOUND = 0x7fffffff;
71
72 /**
73 * Converts "standard Unix time"(in seconds, UTC/GMT) to FileTime
74 */
75 public static final FileTime unixTimeToFileTime(long utime) {
76 return FileTime.from(utime, TimeUnit.SECONDS);
77 }
78
79 /**
80 * Converts FileTime to "standard Unix time".
81 */
82 public static final long fileTimeToUnixTime(FileTime ftime) {
83 return ftime.to(TimeUnit.SECONDS);
84 }
85
86 /**
87 * Converts DOS time to Java time (number of milliseconds since epoch).
88 */
89 public static long dosToJavaTime(long dtime) {
90 int year = (int) (((dtime >> 25) & 0x7f) + 1980);
91 int month = (int) ((dtime >> 21) & 0x0f);
92 int day = (int) ((dtime >> 16) & 0x1f);
93 int hour = (int) ((dtime >> 11) & 0x1f);
94 int minute = (int) ((dtime >> 5) & 0x3f);
95 int second = (int) ((dtime << 1) & 0x3e);
96
97 if (month > 0 && month < 13 && day > 0 && hour < 24 && minute < 60 && second < 60) {
98 try {
99 LocalDateTime ldt = LocalDateTime.of(year, month, day, hour, minute, second);
100 return TimeUnit.MILLISECONDS.convert(ldt.toEpochSecond(
101 ZoneId.systemDefault().getRules().getOffset(ldt)), TimeUnit.SECONDS);
102 } catch (DateTimeException dte) {
103 // ignore
104 }
105 }
106 return overflowDosToJavaTime(year, month, day, hour, minute, second);
107 }
108
109 /*
110 * Deal with corner cases where an arguably mal-formed DOS time is used
111 */
112 @SuppressWarnings("deprecation") // Use of Date constructor
113 private static long overflowDosToJavaTime(int year, int month, int day,
114 int hour, int minute, int second) {
115 return new Date(year - 1900, month - 1, day, hour, minute, second).getTime();
116 }
117
118
119 /**
120 * Converts extended DOS time to Java time, where up to 1999 milliseconds
121 * might be encoded into the upper half of the returned long.
122 *
123 * @param xdostime the extended DOS time value
124 * @return milliseconds since epoch
125 */
126 public static long extendedDosToJavaTime(long xdostime) {
127 long time = dosToJavaTime(xdostime);
128 return time + (xdostime >> 32);
129 }
130
131 /**
132 * Converts Java time to DOS time.
133 */
134 private static long javaToDosTime(LocalDateTime ldt) {
135 int year = ldt.getYear() - 1980;
136 return (year << 25 |
137 ldt.getMonthValue() << 21 |
138 ldt.getDayOfMonth() << 16 |
139 ldt.getHour() << 11 |
140 ldt.getMinute() << 5 |
141 ldt.getSecond() >> 1) & 0xffffffffL;
142 }
143
144 /**
145 * Converts Java time to DOS time, encoding any milliseconds lost
146 * in the conversion into the upper half of the returned long.
147 *
148 * @param time milliseconds since epoch
149 * @return DOS time with 2s remainder encoded into upper half
150 */
151 static long javaToExtendedDosTime(long time) {
152 LocalDateTime ldt = javaEpochToLocalDateTime(time);
153 if (ldt.getYear() >= 1980) {
154 return javaToDosTime(ldt) + ((time % 2000) << 32);
155 }
156 return ZipEntry.DOSTIME_BEFORE_1980;
157 }
158
159 static LocalDateTime javaEpochToLocalDateTime(long time) {
160 Instant instant = Instant.ofEpochMilli(time);
161 return LocalDateTime.ofInstant(instant, ZoneId.systemDefault());
162 }
163
164 /**
165 * Fetches unsigned 16-bit value from byte array at specified offset.
166 * The bytes are assumed to be in Intel (little-endian) byte order.
167 */
168 public static final int get16(byte b[], int off) {
169 return (b[off] & 0xff) | ((b[off + 1] & 0xff) << 8);
170 }
171
172 /**
173 * Fetches unsigned 32-bit value from byte array at specified offset.
174 * The bytes are assumed to be in Intel (little-endian) byte order.
175 */
176 public static final long get32(byte b[], int off) {
177 return (get16(b, off) | ((long)get16(b, off+2) << 16)) & 0xffffffffL;
178 }
179
180 /**
181 * Fetches signed 64-bit value from byte array at specified offset.
182 * The bytes are assumed to be in Intel (little-endian) byte order.
183 */
184 public static final long get64(byte b[], int off) {
185 return get32(b, off) | (get32(b, off+4) << 32);
186 }
187
188 /**
189 * Fetches signed 32-bit value from byte array at specified offset.
190 * The bytes are assumed to be in Intel (little-endian) byte order.
191 *
192 */
193 public static final int get32S(byte b[], int off) {
194 return (get16(b, off) | (get16(b, off+2) << 16));
195 }
196
197 // fields access methods
198 static final int CH(byte[] b, int n) {
199 return b[n] & 0xff ;
200 }
201
202 static final int SH(byte[] b, int n) {
203 return (b[n] & 0xff) | ((b[n + 1] & 0xff) << 8);
204 }
205
206 static final long LG(byte[] b, int n) {
207 return ((SH(b, n)) | (SH(b, n + 2) << 16)) & 0xffffffffL;
208 }
209
210 static final long LL(byte[] b, int n) {
211 return (LG(b, n)) | (LG(b, n + 4) << 32);
212 }
213
214 static final long GETSIG(byte[] b) {
215 return LG(b, 0);
216 }
217
218 /*
219 * File attribute compatibility types of CEN field "version made by"
220 */
221 static final int FILE_ATTRIBUTES_UNIX = 3; // Unix
222
223 /*
224 * Base values for CEN field "version made by"
225 */
226 static final int VERSION_MADE_BY_BASE_UNIX = FILE_ATTRIBUTES_UNIX << 8; // Unix
227
228
229 // local file (LOC) header fields
230 static final long LOCSIG(byte[] b) { return LG(b, 0); } // signature
231 static final int LOCVER(byte[] b) { return SH(b, 4); } // version needed to extract
232 static final int LOCFLG(byte[] b) { return SH(b, 6); } // general purpose bit flags
233 static final int LOCHOW(byte[] b) { return SH(b, 8); } // compression method
234 static final long LOCTIM(byte[] b) { return LG(b, 10);} // modification time
235 static final long LOCCRC(byte[] b) { return LG(b, 14);} // crc of uncompressed data
236 static final long LOCSIZ(byte[] b) { return LG(b, 18);} // compressed data size
237 static final long LOCLEN(byte[] b) { return LG(b, 22);} // uncompressed data size
238 static final int LOCNAM(byte[] b) { return SH(b, 26);} // filename length
239 static final int LOCEXT(byte[] b) { return SH(b, 28);} // extra field length
240
241 // extra local (EXT) header fields
242 static final long EXTCRC(byte[] b) { return LG(b, 4);} // crc of uncompressed data
243 static final long EXTSIZ(byte[] b) { return LG(b, 8);} // compressed size
244 static final long EXTLEN(byte[] b) { return LG(b, 12);} // uncompressed size
245
246 // end of central directory header (END) fields
247 static final int ENDSUB(byte[] b) { return SH(b, 8); } // number of entries on this disk
248 static final int ENDTOT(byte[] b) { return SH(b, 10);} // total number of entries
249 static final long ENDSIZ(byte[] b) { return LG(b, 12);} // central directory size
250 static final long ENDOFF(byte[] b) { return LG(b, 16);} // central directory offset
251 static final int ENDCOM(byte[] b) { return SH(b, 20);} // size of zip file comment
252 static final int ENDCOM(byte[] b, int off) { return SH(b, off + 20);}
253
254 // zip64 end of central directory recoder fields
255 static final long ZIP64_ENDTOD(byte[] b) { return LL(b, 24);} // total number of entries on disk
256 static final long ZIP64_ENDTOT(byte[] b) { return LL(b, 32);} // total number of entries
257 static final long ZIP64_ENDSIZ(byte[] b) { return LL(b, 40);} // central directory size
258 static final long ZIP64_ENDOFF(byte[] b) { return LL(b, 48);} // central directory offset
259 static final long ZIP64_LOCOFF(byte[] b) { return LL(b, 8);} // zip64 end offset
260
261 // central directory header (CEN) fields
262 static final long CENSIG(byte[] b, int pos) { return LG(b, pos + 0); }
263 static final int CENVEM(byte[] b, int pos) { return SH(b, pos + 4); }
264 static final int CENVEM_FA(byte[] b, int pos) { return CH(b, pos + 5); } // file attribute compatibility
265 static final int CENVER(byte[] b, int pos) { return SH(b, pos + 6); }
266 static final int CENFLG(byte[] b, int pos) { return SH(b, pos + 8); }
267 static final int CENHOW(byte[] b, int pos) { return SH(b, pos + 10);}
268 static final long CENTIM(byte[] b, int pos) { return LG(b, pos + 12);}
269 static final long CENCRC(byte[] b, int pos) { return LG(b, pos + 16);}
270 static final long CENSIZ(byte[] b, int pos) { return LG(b, pos + 20);}
271 static final long CENLEN(byte[] b, int pos) { return LG(b, pos + 24);}
272 static final int CENNAM(byte[] b, int pos) { return SH(b, pos + 28);}
273 static final int CENEXT(byte[] b, int pos) { return SH(b, pos + 30);}
274 static final int CENCOM(byte[] b, int pos) { return SH(b, pos + 32);}
275 static final int CENDSK(byte[] b, int pos) { return SH(b, pos + 34);}
276 static final int CENATT(byte[] b, int pos) { return SH(b, pos + 36);}
277 static final long CENATX(byte[] b, int pos) { return LG(b, pos + 38);}
278 static final int CENATX_PERMS(byte[] b, int pos) { return SH(b, pos + 40);} // posix permission data
279 static final long CENOFF(byte[] b, int pos) { return LG(b, pos + 42);}
280
281 // The END header is followed by a variable length comment of size < 64k.
282 static final long END_MAXLEN = 0xFFFF + ENDHDR;
283 static final int READBLOCKSZ = 128;
284
285 /**
286 * Loads zip native library, if not already laoded
287 */
288 static void loadLibrary() {
289 jdk.internal.loader.BootLoader.loadLibrary("zip");
290 }
291
292 private static final Unsafe unsafe = Unsafe.getUnsafe();
293
294 private static final long byteBufferArrayOffset = unsafe.objectFieldOffset(ByteBuffer.class, "hb");
295 private static final long byteBufferOffsetOffset = unsafe.objectFieldOffset(ByteBuffer.class, "offset");
296
297 static byte[] getBufferArray(ByteBuffer byteBuffer) {
298 return (byte[]) unsafe.getReference(byteBuffer, byteBufferArrayOffset);
299 }
300
301 static int getBufferOffset(ByteBuffer byteBuffer) {
302 return unsafe.getInt(byteBuffer, byteBufferOffsetOffset);
303 }
304 }