1 /*
2 * Copyright (c) 2013, 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 package java.util.zip;
27
28 import java.nio.Buffer;
29 import java.nio.ByteBuffer;
30 import java.nio.file.attribute.FileTime;
31 import java.security.AccessController;
32 import java.security.PrivilegedAction;
33 import java.time.DateTimeException;
34 import java.time.Instant;
35 import java.time.LocalDateTime;
36 import java.time.ZoneId;
37 import java.util.Date;
38 import java.util.concurrent.TimeUnit;
39
40 import static java.util.zip.ZipConstants.ENDHDR;
41
42 import jdk.internal.misc.Unsafe;
43 import sun.nio.ch.DirectBuffer;
44
45 class ZipUtils {
46
47 // used to adjust values between Windows and java epoch
48 private static final long WINDOWS_EPOCH_IN_MICROSECONDS = -11644473600000000L;
49
50 // used to indicate the corresponding windows time is not available
51 public static final long WINDOWS_TIME_NOT_AVAILABLE = Long.MIN_VALUE;
52
53 // static final ByteBuffer defaultBuf = ByteBuffer.allocateDirect(0);
54 static final ByteBuffer defaultBuf = ByteBuffer.allocate(0);
55
56 /**
57 * Converts Windows time (in microseconds, UTC/GMT) time to FileTime.
58 */
59 public static final FileTime winTimeToFileTime(long wtime) {
60 return FileTime.from(wtime / 10 + WINDOWS_EPOCH_IN_MICROSECONDS,
61 TimeUnit.MICROSECONDS);
62 }
63
64 /**
65 * Converts FileTime to Windows time.
66 */
67 public static final long fileTimeToWinTime(FileTime ftime) {
68 return (ftime.to(TimeUnit.MICROSECONDS) - WINDOWS_EPOCH_IN_MICROSECONDS) * 10;
69 }
70
71 /**
72 * The upper bound of the 32-bit unix time, the "year 2038 problem".
73 */
74 public static final long UPPER_UNIXTIME_BOUND = 0x7fffffff;
75
76 /**
77 * Converts "standard Unix time"(in seconds, UTC/GMT) to FileTime
78 */
79 public static final FileTime unixTimeToFileTime(long utime) {
80 return FileTime.from(utime, TimeUnit.SECONDS);
81 }
82
83 /**
84 * Converts FileTime to "standard Unix time".
85 */
86 public static final long fileTimeToUnixTime(FileTime ftime) {
87 return ftime.to(TimeUnit.SECONDS);
88 }
89
90 /**
91 /*
92 * Converts DOS time to Java time (number of milliseconds since epoch).
93 */
94 public static long dosToJavaTime(long dtime) {
95 int year = (int) (((dtime >> 25) & 0x7f) + 1980);
96 int month = (int) ((dtime >> 21) & 0x0f);
97 int day = (int) ((dtime >> 16) & 0x1f);
98 int hour = (int) ((dtime >> 11) & 0x1f);
99 int minute = (int) ((dtime >> 5) & 0x3f);
100 int second = (int) ((dtime << 1) & 0x3e);
101
102 if (month > 0 && month < 13 && day > 0 && hour < 24 && minute < 60 && second < 60) {
103 try {
104 LocalDateTime ldt = LocalDateTime.of(year, month, day, hour, minute, second);
105 return TimeUnit.MILLISECONDS.convert(ldt.toEpochSecond(
106 ZoneId.systemDefault().getRules().getOffset(ldt)), TimeUnit.SECONDS);
107 } catch (DateTimeException dte) {
108 // ignore
109 }
110 }
111 return overflowDosToJavaTime(year, month, day, hour, minute, second);
112 }
113
114 /*
115 * Deal with corner cases where an arguably mal-formed DOS time is used
116 */
117 @SuppressWarnings("deprecation") // Use of Date constructor
118 private static long overflowDosToJavaTime(int year, int month, int day,
119 int hour, int minute, int second) {
120 return new Date(year - 1900, month - 1, day, hour, minute, second).getTime();
121 }
122
123
124 /**
125 * Converts extended DOS time to Java time, where up to 1999 milliseconds
126 * might be encoded into the upper half of the returned long.
127 *
128 * @param xdostime the extended DOS time value
129 * @return milliseconds since epoch
130 */
131 public static long extendedDosToJavaTime(long xdostime) {
132 long time = dosToJavaTime(xdostime);
133 return time + (xdostime >> 32);
134 }
135
136 /**
137 * Converts Java time to DOS time.
138 */
139 private static long javaToDosTime(long time) {
140 Instant instant = Instant.ofEpochMilli(time);
141 LocalDateTime ldt = LocalDateTime.ofInstant(
142 instant, ZoneId.systemDefault());
143 int year = ldt.getYear() - 1980;
144 if (year < 0) {
145 return (1 << 21) | (1 << 16);
146 }
147 return (year << 25 |
148 ldt.getMonthValue() << 21 |
149 ldt.getDayOfMonth() << 16 |
150 ldt.getHour() << 11 |
151 ldt.getMinute() << 5 |
152 ldt.getSecond() >> 1) & 0xffffffffL;
153 }
154
155 /**
156 * Converts Java time to DOS time, encoding any milliseconds lost
157 * in the conversion into the upper half of the returned long.
158 *
159 * @param time milliseconds since epoch
160 * @return DOS time with 2s remainder encoded into upper half
161 */
162 public static long javaToExtendedDosTime(long time) {
163 if (time < 0) {
164 return ZipEntry.DOSTIME_BEFORE_1980;
165 }
166 long dostime = javaToDosTime(time);
167 return (dostime != ZipEntry.DOSTIME_BEFORE_1980)
168 ? dostime + ((time % 2000) << 32)
169 : ZipEntry.DOSTIME_BEFORE_1980;
170 }
171
172 /**
173 * Fetches unsigned 16-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 int get16(byte b[], int off) {
177 return (b[off] & 0xff) | ((b[off + 1] & 0xff) << 8);
178 }
179
180 /**
181 * Fetches unsigned 32-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 get32(byte b[], int off) {
185 return (get16(b, off) | ((long)get16(b, off+2) << 16)) & 0xffffffffL;
186 }
187
188 /**
189 * Fetches signed 64-bit value from byte array at specified offset.
190 * The bytes are assumed to be in Intel (little-endian) byte order.
191 */
192 public static final long get64(byte b[], int off) {
193 return get32(b, off) | (get32(b, off+4) << 32);
194 }
195
196 /**
197 * Fetches signed 32-bit value from byte array at specified offset.
198 * The bytes are assumed to be in Intel (little-endian) byte order.
199 *
200 */
201 public static final int get32S(byte b[], int off) {
202 return (get16(b, off) | (get16(b, off+2) << 16));
203 }
204
205 // fields access methods
206 static final int CH(byte[] b, int n) {
207 return b[n] & 0xff ;
208 }
209
210 static final int SH(byte[] b, int n) {
211 return (b[n] & 0xff) | ((b[n + 1] & 0xff) << 8);
212 }
213
214 static final long LG(byte[] b, int n) {
215 return ((SH(b, n)) | (SH(b, n + 2) << 16)) & 0xffffffffL;
216 }
217
218 static final long LL(byte[] b, int n) {
219 return (LG(b, n)) | (LG(b, n + 4) << 32);
220 }
221
222 static final long GETSIG(byte[] b) {
223 return LG(b, 0);
224 }
225
226 // local file (LOC) header fields
227 static final long LOCSIG(byte[] b) { return LG(b, 0); } // signature
228 static final int LOCVER(byte[] b) { return SH(b, 4); } // version needed to extract
229 static final int LOCFLG(byte[] b) { return SH(b, 6); } // general purpose bit flags
230 static final int LOCHOW(byte[] b) { return SH(b, 8); } // compression method
231 static final long LOCTIM(byte[] b) { return LG(b, 10);} // modification time
232 static final long LOCCRC(byte[] b) { return LG(b, 14);} // crc of uncompressed data
233 static final long LOCSIZ(byte[] b) { return LG(b, 18);} // compressed data size
234 static final long LOCLEN(byte[] b) { return LG(b, 22);} // uncompressed data size
235 static final int LOCNAM(byte[] b) { return SH(b, 26);} // filename length
236 static final int LOCEXT(byte[] b) { return SH(b, 28);} // extra field length
237
238 // extra local (EXT) header fields
239 static final long EXTCRC(byte[] b) { return LG(b, 4);} // crc of uncompressed data
240 static final long EXTSIZ(byte[] b) { return LG(b, 8);} // compressed size
241 static final long EXTLEN(byte[] b) { return LG(b, 12);} // uncompressed size
242
243 // end of central directory header (END) fields
244 static final int ENDSUB(byte[] b) { return SH(b, 8); } // number of entries on this disk
245 static final int ENDTOT(byte[] b) { return SH(b, 10);} // total number of entries
246 static final long ENDSIZ(byte[] b) { return LG(b, 12);} // central directory size
247 static final long ENDOFF(byte[] b) { return LG(b, 16);} // central directory offset
248 static final int ENDCOM(byte[] b) { return SH(b, 20);} // size of zip file comment
249 static final int ENDCOM(byte[] b, int off) { return SH(b, off + 20);}
250
251 // zip64 end of central directory recoder fields
252 static final long ZIP64_ENDTOD(byte[] b) { return LL(b, 24);} // total number of entries on disk
253 static final long ZIP64_ENDTOT(byte[] b) { return LL(b, 32);} // total number of entries
254 static final long ZIP64_ENDSIZ(byte[] b) { return LL(b, 40);} // central directory size
255 static final long ZIP64_ENDOFF(byte[] b) { return LL(b, 48);} // central directory offset
256 static final long ZIP64_LOCOFF(byte[] b) { return LL(b, 8);} // zip64 end offset
257
258 // central directory header (CEN) fields
259 static final long CENSIG(byte[] b, int pos) { return LG(b, pos + 0); }
260 static final int CENVEM(byte[] b, int pos) { return SH(b, pos + 4); }
261 static final int CENVER(byte[] b, int pos) { return SH(b, pos + 6); }
262 static final int CENFLG(byte[] b, int pos) { return SH(b, pos + 8); }
263 static final int CENHOW(byte[] b, int pos) { return SH(b, pos + 10);}
264 static final long CENTIM(byte[] b, int pos) { return LG(b, pos + 12);}
265 static final long CENCRC(byte[] b, int pos) { return LG(b, pos + 16);}
266 static final long CENSIZ(byte[] b, int pos) { return LG(b, pos + 20);}
267 static final long CENLEN(byte[] b, int pos) { return LG(b, pos + 24);}
268 static final int CENNAM(byte[] b, int pos) { return SH(b, pos + 28);}
269 static final int CENEXT(byte[] b, int pos) { return SH(b, pos + 30);}
270 static final int CENCOM(byte[] b, int pos) { return SH(b, pos + 32);}
271 static final int CENDSK(byte[] b, int pos) { return SH(b, pos + 34);}
272 static final int CENATT(byte[] b, int pos) { return SH(b, pos + 36);}
273 static final long CENATX(byte[] b, int pos) { return LG(b, pos + 38);}
274 static final long CENOFF(byte[] b, int pos) { return LG(b, pos + 42);}
275
276 // The END header is followed by a variable length comment of size < 64k.
277 static final long END_MAXLEN = 0xFFFF + ENDHDR;
278 static final int READBLOCKSZ = 128;
279
280 /**
281 * Loads zip native library, if not already laoded
282 */
283 static void loadLibrary() {
284 SecurityManager sm = System.getSecurityManager();
285 if (sm == null) {
286 System.loadLibrary("zip");
287 } else {
288 PrivilegedAction<Void> pa = () -> { System.loadLibrary("zip"); return null; };
289 AccessController.doPrivileged(pa);
290 }
291 }
292
293 private static final Unsafe unsafe = Unsafe.getUnsafe();
294
295 private static final long byteBufferArrayOffset = unsafe.objectFieldOffset(ByteBuffer.class, "hb");
296 private static final long byteBufferOffsetOffset = unsafe.objectFieldOffset(ByteBuffer.class, "offset");
297
298 static byte[] getBufferArray(ByteBuffer byteBuffer) {
299 return (byte[]) unsafe.getObject(byteBuffer, byteBufferArrayOffset);
300 }
301
302 static int getBufferOffset(ByteBuffer byteBuffer) {
303 return unsafe.getInt(byteBuffer, byteBufferOffsetOffset);
304 }
305 }