1/* 2 * Copyright (c) 2013, 2016, 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.time.Instant; 30import java.time.LocalDateTime; 31import java.time.ZoneId; 32import java.util.concurrent.TimeUnit; 33 34import static java.util.zip.ZipConstants.ENDHDR; 35 36class ZipUtils { 37 38 // used to adjust values between Windows and java epoch 39 private static final long WINDOWS_EPOCH_IN_MICROSECONDS = -11644473600000000L; 40 41 // used to indicate the corresponding windows time is not available 42 public static final long WINDOWS_TIME_NOT_AVAILABLE = Long.MIN_VALUE; 43 44 /** 45 * Converts Windows time (in microseconds, UTC/GMT) time to FileTime. 46 */ 47 public static final FileTime winTimeToFileTime(long wtime) { 48 return FileTime.from(wtime / 10 + WINDOWS_EPOCH_IN_MICROSECONDS, 49 TimeUnit.MICROSECONDS); 50 } 51 52 /** 53 * Converts FileTime to Windows time. 54 */ 55 public static final long fileTimeToWinTime(FileTime ftime) { 56 return (ftime.to(TimeUnit.MICROSECONDS) - WINDOWS_EPOCH_IN_MICROSECONDS) * 10; 57 } 58 59 /** 60 * The upper bound of the 32-bit unix time, the "year 2038 problem". 61 */ 62 public static final long UPPER_UNIXTIME_BOUND = 0x7fffffff; 63 64 /** 65 * Converts "standard Unix time"(in seconds, UTC/GMT) to FileTime 66 */ 67 public static final FileTime unixTimeToFileTime(long utime) { 68 return FileTime.from(utime, TimeUnit.SECONDS); 69 } 70 71 /** 72 * Converts FileTime to "standard Unix time". 73 */ 74 public static final long fileTimeToUnixTime(FileTime ftime) { 75 return ftime.to(TimeUnit.SECONDS); 76 } 77 78 /** 79 * Converts DOS time to Java time (number of milliseconds since epoch). 80 */ 81 public static long dosToJavaTime(long dtime) { 82 LocalDateTime ldt = LocalDateTime.of( 83 (int) (((dtime >> 25) & 0x7f) + 1980), 84 (int) ((dtime >> 21) & 0x0f), 85 (int) ((dtime >> 16) & 0x1f), 86 (int) ((dtime >> 11) & 0x1f), 87 (int) ((dtime >> 5) & 0x3f), 88 (int) ((dtime << 1) & 0x3e)); 89 return TimeUnit.MILLISECONDS.convert(ldt.toEpochSecond( 90 ZoneId.systemDefault().getRules().getOffset(ldt)), TimeUnit.SECONDS); 91 } 92 93 /** 94 * Converts extended DOS time to Java time, where up to 1999 milliseconds 95 * might be encoded into the upper half of the returned long. 96 * 97 * @param xdostime the extended DOS time value 98 * @return milliseconds since epoch 99 */ 100 public static long extendedDosToJavaTime(long xdostime) { 101 long time = dosToJavaTime(xdostime); 102 return time + (xdostime >> 32); 103 } 104 105 /** 106 * Converts Java time to DOS time. 107 */ 108 private static long javaToDosTime(long time) { 109 Instant instant = Instant.ofEpochMilli(time); 110 LocalDateTime ldt = LocalDateTime.ofInstant( 111 instant, ZoneId.systemDefault()); 112 int year = ldt.getYear() - 1980; 113 if (year < 0) { 114 return (1 << 21) | (1 << 16); 115 } 116 return (year << 25 | 117 ldt.getMonthValue() << 21 | 118 ldt.getDayOfMonth() << 16 | 119 ldt.getHour() << 11 | 120 ldt.getMinute() << 5 | 121 ldt.getSecond() >> 1) & 0xffffffffL; 122 } 123 124 /** 125 * Converts Java time to DOS time, encoding any milliseconds lost 126 * in the conversion into the upper half of the returned long. 127 * 128 * @param time milliseconds since epoch 129 * @return DOS time with 2s remainder encoded into upper half 130 */ 131 public static long javaToExtendedDosTime(long time) { 132 if (time < 0) { 133 return ZipEntry.DOSTIME_BEFORE_1980; 134 } 135 long dostime = javaToDosTime(time); 136 return (dostime != ZipEntry.DOSTIME_BEFORE_1980) 137 ? dostime + ((time % 2000) << 32) 138 : ZipEntry.DOSTIME_BEFORE_1980; 139 } 140 141 /** 142 * Fetches unsigned 16-bit value from byte array at specified offset. 143 * The bytes are assumed to be in Intel (little-endian) byte order. 144 */ 145 public static final int get16(byte b[], int off) { 146 return (b[off] & 0xff) | ((b[off + 1] & 0xff) << 8); 147 } 148 149 /** 150 * Fetches unsigned 32-bit value from byte array at specified offset. 151 * The bytes are assumed to be in Intel (little-endian) byte order. 152 */ 153 public static final long get32(byte b[], int off) { 154 return (get16(b, off) | ((long)get16(b, off+2) << 16)) & 0xffffffffL; 155 } 156 157 /** 158 * Fetches signed 64-bit value from byte array at specified offset. 159 * The bytes are assumed to be in Intel (little-endian) byte order. 160 */ 161 public static final long get64(byte b[], int off) { 162 return get32(b, off) | (get32(b, off+4) << 32); 163 } 164 165 /** 166 * Fetches signed 32-bit value from byte array at specified offset. 167 * The bytes are assumed to be in Intel (little-endian) byte order. 168 * 169 */ 170 public static final int get32S(byte b[], int off) { 171 return (get16(b, off) | (get16(b, off+2) << 16)); 172 } 173 174 // fields access methods 175 static final int CH(byte[] b, int n) { 176 return b[n] & 0xff ; 177 } 178 179 static final int SH(byte[] b, int n) { 180 return (b[n] & 0xff) | ((b[n + 1] & 0xff) << 8); 181 } 182 183 static final long LG(byte[] b, int n) { 184 return ((SH(b, n)) | (SH(b, n + 2) << 16)) & 0xffffffffL; 185 } 186 187 static final long LL(byte[] b, int n) { 188 return (LG(b, n)) | (LG(b, n + 4) << 32); 189 } 190 191 static final long GETSIG(byte[] b) { 192 return LG(b, 0); 193 } 194 195 // local file (LOC) header fields 196 static final long LOCSIG(byte[] b) { return LG(b, 0); } // signature 197 static final int LOCVER(byte[] b) { return SH(b, 4); } // version needed to extract 198 static final int LOCFLG(byte[] b) { return SH(b, 6); } // general purpose bit flags 199 static final int LOCHOW(byte[] b) { return SH(b, 8); } // compression method 200 static final long LOCTIM(byte[] b) { return LG(b, 10);} // modification time 201 static final long LOCCRC(byte[] b) { return LG(b, 14);} // crc of uncompressed data 202 static final long LOCSIZ(byte[] b) { return LG(b, 18);} // compressed data size 203 static final long LOCLEN(byte[] b) { return LG(b, 22);} // uncompressed data size 204 static final int LOCNAM(byte[] b) { return SH(b, 26);} // filename length 205 static final int LOCEXT(byte[] b) { return SH(b, 28);} // extra field length 206 207 // extra local (EXT) header fields 208 static final long EXTCRC(byte[] b) { return LG(b, 4);} // crc of uncompressed data 209 static final long EXTSIZ(byte[] b) { return LG(b, 8);} // compressed size 210 static final long EXTLEN(byte[] b) { return LG(b, 12);} // uncompressed size 211 212 // end of central directory header (END) fields 213 static final int ENDSUB(byte[] b) { return SH(b, 8); } // number of entries on this disk 214 static final int ENDTOT(byte[] b) { return SH(b, 10);} // total number of entries 215 static final long ENDSIZ(byte[] b) { return LG(b, 12);} // central directory size 216 static final long ENDOFF(byte[] b) { return LG(b, 16);} // central directory offset 217 static final int ENDCOM(byte[] b) { return SH(b, 20);} // size of zip file comment 218 static final int ENDCOM(byte[] b, int off) { return SH(b, off + 20);} 219 220 // zip64 end of central directory recoder fields 221 static final long ZIP64_ENDTOD(byte[] b) { return LL(b, 24);} // total number of entries on disk 222 static final long ZIP64_ENDTOT(byte[] b) { return LL(b, 32);} // total number of entries 223 static final long ZIP64_ENDSIZ(byte[] b) { return LL(b, 40);} // central directory size 224 static final long ZIP64_ENDOFF(byte[] b) { return LL(b, 48);} // central directory offset 225 static final long ZIP64_LOCOFF(byte[] b) { return LL(b, 8);} // zip64 end offset 226 227 // central directory header (CEN) fields 228 static final long CENSIG(byte[] b, int pos) { return LG(b, pos + 0); } 229 static final int CENVEM(byte[] b, int pos) { return SH(b, pos + 4); } 230 static final int CENVER(byte[] b, int pos) { return SH(b, pos + 6); } 231 static final int CENFLG(byte[] b, int pos) { return SH(b, pos + 8); } 232 static final int CENHOW(byte[] b, int pos) { return SH(b, pos + 10);} 233 static final long CENTIM(byte[] b, int pos) { return LG(b, pos + 12);} 234 static final long CENCRC(byte[] b, int pos) { return LG(b, pos + 16);} 235 static final long CENSIZ(byte[] b, int pos) { return LG(b, pos + 20);} 236 static final long CENLEN(byte[] b, int pos) { return LG(b, pos + 24);} 237 static final int CENNAM(byte[] b, int pos) { return SH(b, pos + 28);} 238 static final int CENEXT(byte[] b, int pos) { return SH(b, pos + 30);} 239 static final int CENCOM(byte[] b, int pos) { return SH(b, pos + 32);} 240 static final int CENDSK(byte[] b, int pos) { return SH(b, pos + 34);} 241 static final int CENATT(byte[] b, int pos) { return SH(b, pos + 36);} 242 static final long CENATX(byte[] b, int pos) { return LG(b, pos + 38);} 243 static final long CENOFF(byte[] b, int pos) { return LG(b, pos + 42);} 244 245 // The END header is followed by a variable length comment of size < 64k. 246 static final long END_MAXLEN = 0xFFFF + ENDHDR; 247 static final int READBLOCKSZ = 128; 248} 249