1/* 2 * Copyright (c) 2013, 2017, 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 26package java.util.zip; 27 28import java.nio.file.attribute.FileTime; 29import java.security.AccessController; 30import java.security.PrivilegedAction; 31import java.time.Instant; 32import java.time.LocalDateTime; 33import java.time.ZoneId; 34import java.util.concurrent.TimeUnit; 35 36import static java.util.zip.ZipConstants.ENDHDR; 37 38class ZipUtils { 39 40 // used to adjust values between Windows and java epoch 41 private static final long WINDOWS_EPOCH_IN_MICROSECONDS = -11644473600000000L; 42 43 // used to indicate the corresponding windows time is not available 44 public static final long WINDOWS_TIME_NOT_AVAILABLE = Long.MIN_VALUE; 45 46 /** 47 * Converts Windows time (in microseconds, UTC/GMT) time to FileTime. 48 */ 49 public static final FileTime winTimeToFileTime(long wtime) { 50 return FileTime.from(wtime / 10 + WINDOWS_EPOCH_IN_MICROSECONDS, 51 TimeUnit.MICROSECONDS); 52 } 53 54 /** 55 * Converts FileTime to Windows time. 56 */ 57 public static final long fileTimeToWinTime(FileTime ftime) { 58 return (ftime.to(TimeUnit.MICROSECONDS) - WINDOWS_EPOCH_IN_MICROSECONDS) * 10; 59 } 60 61 /** 62 * The upper bound of the 32-bit unix time, the "year 2038 problem". 63 */ 64 public static final long UPPER_UNIXTIME_BOUND = 0x7fffffff; 65 66 /** 67 * Converts "standard Unix time"(in seconds, UTC/GMT) to FileTime 68 */ 69 public static final FileTime unixTimeToFileTime(long utime) { 70 return FileTime.from(utime, TimeUnit.SECONDS); 71 } 72 73 /** 74 * Converts FileTime to "standard Unix time". 75 */ 76 public static final long fileTimeToUnixTime(FileTime ftime) { 77 return ftime.to(TimeUnit.SECONDS); 78 } 79 80 /** 81 * Converts DOS time to Java time (number of milliseconds since epoch). 82 */ 83 public static long dosToJavaTime(long dtime) { 84 int year; 85 int month; 86 int day; 87 int hour = (int) ((dtime >> 11) & 0x1f); 88 int minute = (int) ((dtime >> 5) & 0x3f); 89 int second = (int) ((dtime << 1) & 0x3e); 90 if ((dtime >> 16) == 0) { 91 // Interpret the 0 DOS date as 1979-11-30 for compatibility with 92 // other implementations. 93 year = 1979; 94 month = 11; 95 day = 30; 96 } else { 97 year = (int) (((dtime >> 25) & 0x7f) + 1980); 98 month = (int) ((dtime >> 21) & 0x0f); 99 day = (int) ((dtime >> 16) & 0x1f); 100 } 101 LocalDateTime ldt = LocalDateTime.of(year, month, day, hour, minute, second); 102 return TimeUnit.MILLISECONDS.convert(ldt.toEpochSecond( 103 ZoneId.systemDefault().getRules().getOffset(ldt)), TimeUnit.SECONDS); 104 } 105 106 /** 107 * Converts extended DOS time to Java time, where up to 1999 milliseconds 108 * might be encoded into the upper half of the returned long. 109 * 110 * @param xdostime the extended DOS time value 111 * @return milliseconds since epoch 112 */ 113 public static long extendedDosToJavaTime(long xdostime) { 114 long time = dosToJavaTime(xdostime); 115 return time + (xdostime >> 32); 116 } 117 118 /** 119 * Converts Java time to DOS time. 120 */ 121 private static long javaToDosTime(long time) { 122 Instant instant = Instant.ofEpochMilli(time); 123 LocalDateTime ldt = LocalDateTime.ofInstant( 124 instant, ZoneId.systemDefault()); 125 int year = ldt.getYear() - 1980; 126 if (year < 0) { 127 return (1 << 21) | (1 << 16); 128 } 129 return (year << 25 | 130 ldt.getMonthValue() << 21 | 131 ldt.getDayOfMonth() << 16 | 132 ldt.getHour() << 11 | 133 ldt.getMinute() << 5 | 134 ldt.getSecond() >> 1) & 0xffffffffL; 135 } 136 137 /** 138 * Converts Java time to DOS time, encoding any milliseconds lost 139 * in the conversion into the upper half of the returned long. 140 * 141 * @param time milliseconds since epoch 142 * @return DOS time with 2s remainder encoded into upper half 143 */ 144 public static long javaToExtendedDosTime(long time) { 145 if (time < 0) { 146 return ZipEntry.DOSTIME_BEFORE_1980; 147 } 148 long dostime = javaToDosTime(time); 149 return (dostime != ZipEntry.DOSTIME_BEFORE_1980) 150 ? dostime + ((time % 2000) << 32) 151 : ZipEntry.DOSTIME_BEFORE_1980; 152 } 153 154 /** 155 * Fetches unsigned 16-bit value from byte array at specified offset. 156 * The bytes are assumed to be in Intel (little-endian) byte order. 157 */ 158 public static final int get16(byte b[], int off) { 159 return (b[off] & 0xff) | ((b[off + 1] & 0xff) << 8); 160 } 161 162 /** 163 * Fetches unsigned 32-bit value from byte array at specified offset. 164 * The bytes are assumed to be in Intel (little-endian) byte order. 165 */ 166 public static final long get32(byte b[], int off) { 167 return (get16(b, off) | ((long)get16(b, off+2) << 16)) & 0xffffffffL; 168 } 169 170 /** 171 * Fetches signed 64-bit value from byte array at specified offset. 172 * The bytes are assumed to be in Intel (little-endian) byte order. 173 */ 174 public static final long get64(byte b[], int off) { 175 return get32(b, off) | (get32(b, off+4) << 32); 176 } 177 178 /** 179 * Fetches signed 32-bit value from byte array at specified offset. 180 * The bytes are assumed to be in Intel (little-endian) byte order. 181 * 182 */ 183 public static final int get32S(byte b[], int off) { 184 return (get16(b, off) | (get16(b, off+2) << 16)); 185 } 186 187 // fields access methods 188 static final int CH(byte[] b, int n) { 189 return b[n] & 0xff ; 190 } 191 192 static final int SH(byte[] b, int n) { 193 return (b[n] & 0xff) | ((b[n + 1] & 0xff) << 8); 194 } 195 196 static final long LG(byte[] b, int n) { 197 return ((SH(b, n)) | (SH(b, n + 2) << 16)) & 0xffffffffL; 198 } 199 200 static final long LL(byte[] b, int n) { 201 return (LG(b, n)) | (LG(b, n + 4) << 32); 202 } 203 204 static final long GETSIG(byte[] b) { 205 return LG(b, 0); 206 } 207 208 // local file (LOC) header fields 209 static final long LOCSIG(byte[] b) { return LG(b, 0); } // signature 210 static final int LOCVER(byte[] b) { return SH(b, 4); } // version needed to extract 211 static final int LOCFLG(byte[] b) { return SH(b, 6); } // general purpose bit flags 212 static final int LOCHOW(byte[] b) { return SH(b, 8); } // compression method 213 static final long LOCTIM(byte[] b) { return LG(b, 10);} // modification time 214 static final long LOCCRC(byte[] b) { return LG(b, 14);} // crc of uncompressed data 215 static final long LOCSIZ(byte[] b) { return LG(b, 18);} // compressed data size 216 static final long LOCLEN(byte[] b) { return LG(b, 22);} // uncompressed data size 217 static final int LOCNAM(byte[] b) { return SH(b, 26);} // filename length 218 static final int LOCEXT(byte[] b) { return SH(b, 28);} // extra field length 219 220 // extra local (EXT) header fields 221 static final long EXTCRC(byte[] b) { return LG(b, 4);} // crc of uncompressed data 222 static final long EXTSIZ(byte[] b) { return LG(b, 8);} // compressed size 223 static final long EXTLEN(byte[] b) { return LG(b, 12);} // uncompressed size 224 225 // end of central directory header (END) fields 226 static final int ENDSUB(byte[] b) { return SH(b, 8); } // number of entries on this disk 227 static final int ENDTOT(byte[] b) { return SH(b, 10);} // total number of entries 228 static final long ENDSIZ(byte[] b) { return LG(b, 12);} // central directory size 229 static final long ENDOFF(byte[] b) { return LG(b, 16);} // central directory offset 230 static final int ENDCOM(byte[] b) { return SH(b, 20);} // size of zip file comment 231 static final int ENDCOM(byte[] b, int off) { return SH(b, off + 20);} 232 233 // zip64 end of central directory recoder fields 234 static final long ZIP64_ENDTOD(byte[] b) { return LL(b, 24);} // total number of entries on disk 235 static final long ZIP64_ENDTOT(byte[] b) { return LL(b, 32);} // total number of entries 236 static final long ZIP64_ENDSIZ(byte[] b) { return LL(b, 40);} // central directory size 237 static final long ZIP64_ENDOFF(byte[] b) { return LL(b, 48);} // central directory offset 238 static final long ZIP64_LOCOFF(byte[] b) { return LL(b, 8);} // zip64 end offset 239 240 // central directory header (CEN) fields 241 static final long CENSIG(byte[] b, int pos) { return LG(b, pos + 0); } 242 static final int CENVEM(byte[] b, int pos) { return SH(b, pos + 4); } 243 static final int CENVER(byte[] b, int pos) { return SH(b, pos + 6); } 244 static final int CENFLG(byte[] b, int pos) { return SH(b, pos + 8); } 245 static final int CENHOW(byte[] b, int pos) { return SH(b, pos + 10);} 246 static final long CENTIM(byte[] b, int pos) { return LG(b, pos + 12);} 247 static final long CENCRC(byte[] b, int pos) { return LG(b, pos + 16);} 248 static final long CENSIZ(byte[] b, int pos) { return LG(b, pos + 20);} 249 static final long CENLEN(byte[] b, int pos) { return LG(b, pos + 24);} 250 static final int CENNAM(byte[] b, int pos) { return SH(b, pos + 28);} 251 static final int CENEXT(byte[] b, int pos) { return SH(b, pos + 30);} 252 static final int CENCOM(byte[] b, int pos) { return SH(b, pos + 32);} 253 static final int CENDSK(byte[] b, int pos) { return SH(b, pos + 34);} 254 static final int CENATT(byte[] b, int pos) { return SH(b, pos + 36);} 255 static final long CENATX(byte[] b, int pos) { return LG(b, pos + 38);} 256 static final long CENOFF(byte[] b, int pos) { return LG(b, pos + 42);} 257 258 // The END header is followed by a variable length comment of size < 64k. 259 static final long END_MAXLEN = 0xFFFF + ENDHDR; 260 static final int READBLOCKSZ = 128; 261 262 /** 263 * Loads zip native library, if not already laoded 264 */ 265 static void loadLibrary() { 266 SecurityManager sm = System.getSecurityManager(); 267 if (sm == null) { 268 System.loadLibrary("zip"); 269 } else { 270 PrivilegedAction<Void> pa = () -> { System.loadLibrary("zip"); return null; }; 271 AccessController.doPrivileged(pa); 272 } 273 } 274} 275