1 /*
2 * Copyright (c) 2013, 2019, 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(long time) {
135 Instant instant = Instant.ofEpochMilli(time);
136 LocalDateTime ldt = LocalDateTime.ofInstant(
137 instant, ZoneId.systemDefault());
138 int year = ldt.getYear() - 1980;
139 if (year < 0) {
140 return (1 << 21) | (1 << 16);
141 }
142 return (year << 25 |
143 ldt.getMonthValue() << 21 |
144 ldt.getDayOfMonth() << 16 |
145 ldt.getHour() << 11 |
146 ldt.getMinute() << 5 |
147 ldt.getSecond() >> 1) & 0xffffffffL;
148 }
149
150 /**
151 * Converts Java time to DOS time, encoding any milliseconds lost
152 * in the conversion into the upper half of the returned long.
153 *
154 * @param time milliseconds since epoch
155 * @return DOS time with 2s remainder encoded into upper half
156 */
157 public static long javaToExtendedDosTime(long time) {
158 if (time < 0) {
159 return ZipEntry.DOSTIME_BEFORE_1980;
160 }
161 long dostime = javaToDosTime(time);
162 return (dostime != ZipEntry.DOSTIME_BEFORE_1980)
163 ? dostime + ((time % 2000) << 32)
164 : ZipEntry.DOSTIME_BEFORE_1980;
165 }
166
167 /**
168 * Fetches unsigned 16-bit value from byte array at specified offset.
169 * The bytes are assumed to be in Intel (little-endian) byte order.
170 */
171 public static final int get16(byte b[], int off) {
172 return (b[off] & 0xff) | ((b[off + 1] & 0xff) << 8);
173 }
174
175 /**
176 * Fetches unsigned 32-bit value from byte array at specified offset.
177 * The bytes are assumed to be in Intel (little-endian) byte order.
178 */
179 public static final long get32(byte b[], int off) {
180 return (get16(b, off) | ((long)get16(b, off+2) << 16)) & 0xffffffffL;
181 }
182
183 /**
184 * Fetches signed 64-bit value from byte array at specified offset.
185 * The bytes are assumed to be in Intel (little-endian) byte order.
186 */
187 public static final long get64(byte b[], int off) {
188 return get32(b, off) | (get32(b, off+4) << 32);
189 }
190
191 /**
192 * Fetches signed 32-bit value from byte array at specified offset.
193 * The bytes are assumed to be in Intel (little-endian) byte order.
194 *
195 */
196 public static final int get32S(byte b[], int off) {
197 return (get16(b, off) | (get16(b, off+2) << 16));
198 }
199
200 // fields access methods
201 static final int CH(byte[] b, int n) {
202 return b[n] & 0xff ;
203 }
204
205 static final int SH(byte[] b, int n) {
206 return (b[n] & 0xff) | ((b[n + 1] & 0xff) << 8);
207 }
208
209 static final long LG(byte[] b, int n) {
210 return ((SH(b, n)) | (SH(b, n + 2) << 16)) & 0xffffffffL;
211 }
212
213 static final long LL(byte[] b, int n) {
214 return (LG(b, n)) | (LG(b, n + 4) << 32);
215 }
216
217 static final long GETSIG(byte[] b) {
218 return LG(b, 0);
219 }
220
221 // local file (LOC) header fields
222 static final long LOCSIG(byte[] b) { return LG(b, 0); } // signature
223 static final int LOCVER(byte[] b) { return SH(b, 4); } // version needed to extract
224 static final int LOCFLG(byte[] b) { return SH(b, 6); } // general purpose bit flags
225 static final int LOCHOW(byte[] b) { return SH(b, 8); } // compression method
226 static final long LOCTIM(byte[] b) { return LG(b, 10);} // modification time
227 static final long LOCCRC(byte[] b) { return LG(b, 14);} // crc of uncompressed data
228 static final long LOCSIZ(byte[] b) { return LG(b, 18);} // compressed data size
229 static final long LOCLEN(byte[] b) { return LG(b, 22);} // uncompressed data size
230 static final int LOCNAM(byte[] b) { return SH(b, 26);} // filename length
231 static final int LOCEXT(byte[] b) { return SH(b, 28);} // extra field length
232
233 // extra local (EXT) header fields
234 static final long EXTCRC(byte[] b) { return LG(b, 4);} // crc of uncompressed data
235 static final long EXTSIZ(byte[] b) { return LG(b, 8);} // compressed size
236 static final long EXTLEN(byte[] b) { return LG(b, 12);} // uncompressed size
237
238 // end of central directory header (END) fields
239 static final int ENDSUB(byte[] b) { return SH(b, 8); } // number of entries on this disk
240 static final int ENDTOT(byte[] b) { return SH(b, 10);} // total number of entries
241 static final long ENDSIZ(byte[] b) { return LG(b, 12);} // central directory size
242 static final long ENDOFF(byte[] b) { return LG(b, 16);} // central directory offset
243 static final int ENDCOM(byte[] b) { return SH(b, 20);} // size of zip file comment
244 static final int ENDCOM(byte[] b, int off) { return SH(b, off + 20);}
245
246 // zip64 end of central directory recoder fields
247 static final long ZIP64_ENDTOD(byte[] b) { return LL(b, 24);} // total number of entries on disk
248 static final long ZIP64_ENDTOT(byte[] b) { return LL(b, 32);} // total number of entries
249 static final long ZIP64_ENDSIZ(byte[] b) { return LL(b, 40);} // central directory size
250 static final long ZIP64_ENDOFF(byte[] b) { return LL(b, 48);} // central directory offset
251 static final long ZIP64_LOCOFF(byte[] b) { return LL(b, 8);} // zip64 end offset
252
253 // central directory header (CEN) fields
254 static final long CENSIG(byte[] b, int pos) { return LG(b, pos + 0); }
255 static final int CENVEM(byte[] b, int pos) { return SH(b, pos + 4); }
256 static final int CENVER(byte[] b, int pos) { return SH(b, pos + 6); }
257 static final int CENFLG(byte[] b, int pos) { return SH(b, pos + 8); }
258 static final int CENHOW(byte[] b, int pos) { return SH(b, pos + 10);}
259 static final long CENTIM(byte[] b, int pos) { return LG(b, pos + 12);}
260 static final long CENCRC(byte[] b, int pos) { return LG(b, pos + 16);}
261 static final long CENSIZ(byte[] b, int pos) { return LG(b, pos + 20);}
262 static final long CENLEN(byte[] b, int pos) { return LG(b, pos + 24);}
263 static final int CENNAM(byte[] b, int pos) { return SH(b, pos + 28);}
264 static final int CENEXT(byte[] b, int pos) { return SH(b, pos + 30);}
265 static final int CENCOM(byte[] b, int pos) { return SH(b, pos + 32);}
266 static final int CENDSK(byte[] b, int pos) { return SH(b, pos + 34);}
267 static final int CENATT(byte[] b, int pos) { return SH(b, pos + 36);}
268 static final long CENATX(byte[] b, int pos) { return LG(b, pos + 38);}
269 static final long CENOFF(byte[] b, int pos) { return LG(b, pos + 42);}
270
271 // The END header is followed by a variable length comment of size < 64k.
272 static final long END_MAXLEN = 0xFFFF + ENDHDR;
273 static final int READBLOCKSZ = 128;
274
275 /**
276 * Loads zip native library, if not already laoded
277 */
278 static void loadLibrary() {
279 jdk.internal.loader.BootLoader.loadLibrary("zip");
280 }
281
282 private static final Unsafe unsafe = Unsafe.getUnsafe();
283
284 private static final long byteBufferArrayOffset = unsafe.objectFieldOffset(ByteBuffer.class, "hb");
285 private static final long byteBufferOffsetOffset = unsafe.objectFieldOffset(ByteBuffer.class, "offset");
286
287 static byte[] getBufferArray(ByteBuffer byteBuffer) {
288 return (byte[]) unsafe.getReference(byteBuffer, byteBufferArrayOffset);
289 }
290
291 static int getBufferOffset(ByteBuffer byteBuffer) {
292 return unsafe.getInt(byteBuffer, byteBufferOffsetOffset);
293 }
294 }