001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019package org.apache.commons.compress.archivers.zip; 020 021import java.io.Serializable; 022import java.util.Arrays; 023import java.util.Date; 024import java.util.zip.ZipException; 025 026/** 027 * <p>An extra field that stores additional file and directory timestamp data 028 * for zip entries. Each zip entry can include up to three timestamps 029 * (modify, access, create*). The timestamps are stored as 32 bit signed 030 * integers representing seconds since UNIX epoch (Jan 1st, 1970, UTC). 031 * This field improves on zip's default timestamp granularity, since it 032 * allows one to store additional timestamps, and, in addition, the timestamps 033 * are stored using per-second granularity (zip's default behaviour can only store 034 * timestamps to the nearest <em>even</em> second). 035 * </p><p> 036 * Unfortunately, 32 (signed) bits can only store dates up to the year 2037, 037 * and so this extra field will eventually be obsolete. Enjoy it while it lasts! 038 * </p> 039 * <ul> 040 * <li><b>modifyTime:</b> 041 * most recent time of file/directory modification 042 * (or file/dir creation if the entry has not been 043 * modified since it was created). 044 * </li> 045 * <li><b>accessTime:</b> 046 * most recent time file/directory was opened 047 * (e.g., read from disk). Many people disable 048 * their operating systems from updating this value 049 * using the NOATIME mount option to optimize disk behaviour, 050 * and thus it's not always reliable. In those cases 051 * it's always equal to modifyTime. 052 * </li> 053 * <li><b>*createTime:</b> 054 * modern linux file systems (e.g., ext2 and newer) 055 * do not appear to store a value like this, and so 056 * it's usually omitted altogether in the zip extra 057 * field. Perhaps other unix systems track this. 058 * </li></ul> 059 * <p> 060 * We're using the field definition given in Info-Zip's source archive: 061 * zip-3.0.tar.gz/proginfo/extrafld.txt 062 * </p> 063 * <pre> 064 * Value Size Description 065 * ----- ---- ----------- 066 * 0x5455 Short tag for this extra block type ("UT") 067 * TSize Short total data size for this block 068 * Flags Byte info bits 069 * (ModTime) Long time of last modification (UTC/GMT) 070 * (AcTime) Long time of last access (UTC/GMT) 071 * (CrTime) Long time of original creation (UTC/GMT) 072 * 073 * Central-header version: 074 * 075 * Value Size Description 076 * ----- ---- ----------- 077 * 0x5455 Short tag for this extra block type ("UT") 078 * TSize Short total data size for this block 079 * Flags Byte info bits (refers to local header!) 080 * (ModTime) Long time of last modification (UTC/GMT) 081 * </pre> 082 * @since 1.5 083 */ 084public class X5455_ExtendedTimestamp implements ZipExtraField, Cloneable, Serializable { 085 private static final ZipShort HEADER_ID = new ZipShort(0x5455); 086 private static final long serialVersionUID = 1L; 087 088 /** 089 * The bit set inside the flags by when the last modification time 090 * is present in this extra field. 091 */ 092 public static final byte MODIFY_TIME_BIT = 1; 093 /** 094 * The bit set inside the flags by when the lasr access time is 095 * present in this extra field. 096 */ 097 public static final byte ACCESS_TIME_BIT = 2; 098 /** 099 * The bit set inside the flags by when the original creation time 100 * is present in this extra field. 101 */ 102 public static final byte CREATE_TIME_BIT = 4; 103 104 // The 3 boolean fields (below) come from this flags byte. The remaining 5 bits 105 // are ignored according to the current version of the spec (December 2012). 106 private byte flags; 107 108 // Note: even if bit1 and bit2 are set, the Central data will still not contain 109 // access/create fields: only local data ever holds those! This causes 110 // some of our implementation to look a little odd, with seemingly spurious 111 // != null and length checks. 112 private boolean bit0_modifyTimePresent; 113 private boolean bit1_accessTimePresent; 114 private boolean bit2_createTimePresent; 115 116 private ZipLong modifyTime; 117 private ZipLong accessTime; 118 private ZipLong createTime; 119 120 /** 121 * Constructor for X5455_ExtendedTimestamp. 122 */ 123 public X5455_ExtendedTimestamp() {} 124 125 /** 126 * The Header-ID. 127 * 128 * @return the value for the header id for this extrafield 129 */ 130 @Override 131 public ZipShort getHeaderId() { 132 return HEADER_ID; 133 } 134 135 /** 136 * Length of the extra field in the local file data - without 137 * Header-ID or length specifier. 138 * 139 * @return a <code>ZipShort</code> for the length of the data of this extra field 140 */ 141 @Override 142 public ZipShort getLocalFileDataLength() { 143 return new ZipShort(1 + 144 (bit0_modifyTimePresent ? 4 : 0) + 145 (bit1_accessTimePresent && accessTime != null ? 4 : 0) + 146 (bit2_createTimePresent && createTime != null ? 4 : 0) 147 ); 148 } 149 150 /** 151 * Length of the extra field in the local file data - without 152 * Header-ID or length specifier. 153 * 154 * <p>For X5455 the central length is often smaller than the 155 * local length, because central cannot contain access or create 156 * timestamps.</p> 157 * 158 * @return a <code>ZipShort</code> for the length of the data of this extra field 159 */ 160 @Override 161 public ZipShort getCentralDirectoryLength() { 162 return new ZipShort(1 + 163 (bit0_modifyTimePresent ? 4 : 0) 164 ); 165 } 166 167 /** 168 * The actual data to put into local file data - without Header-ID 169 * or length specifier. 170 * 171 * @return get the data 172 */ 173 @Override 174 public byte[] getLocalFileDataData() { 175 final byte[] data = new byte[getLocalFileDataLength().getValue()]; 176 int pos = 0; 177 data[pos++] = 0; 178 if (bit0_modifyTimePresent) { 179 data[0] |= MODIFY_TIME_BIT; 180 System.arraycopy(modifyTime.getBytes(), 0, data, pos, 4); 181 pos += 4; 182 } 183 if (bit1_accessTimePresent && accessTime != null) { 184 data[0] |= ACCESS_TIME_BIT; 185 System.arraycopy(accessTime.getBytes(), 0, data, pos, 4); 186 pos += 4; 187 } 188 if (bit2_createTimePresent && createTime != null) { 189 data[0] |= CREATE_TIME_BIT; 190 System.arraycopy(createTime.getBytes(), 0, data, pos, 4); 191 pos += 4; // NOSONAR - assignment as documentation 192 } 193 return data; 194 } 195 196 /** 197 * The actual data to put into central directory data - without Header-ID 198 * or length specifier. 199 * 200 * @return the central directory data 201 */ 202 @Override 203 public byte[] getCentralDirectoryData() { 204 // Truncate out create & access time (last 8 bytes) from 205 // the copy of the local data we obtained: 206 return Arrays.copyOf(getLocalFileDataData(), getCentralDirectoryLength().getValue()); 207 } 208 209 /** 210 * Populate data from this array as if it was in local file data. 211 * 212 * @param data an array of bytes 213 * @param offset the start offset 214 * @param length the number of bytes in the array from offset 215 * @throws java.util.zip.ZipException on error 216 */ 217 @Override 218 public void parseFromLocalFileData( 219 final byte[] data, int offset, final int length 220 ) throws ZipException { 221 reset(); 222 if (length < 1) { 223 throw new ZipException("X5455_ExtendedTimestamp too short, only " + length + " bytes"); 224 } 225 final int len = offset + length; 226 setFlags(data[offset++]); 227 if (bit0_modifyTimePresent && offset + 4 <= len) { 228 modifyTime = new ZipLong(data, offset); 229 offset += 4; 230 } 231 if (bit1_accessTimePresent && offset + 4 <= len) { 232 accessTime = new ZipLong(data, offset); 233 offset += 4; 234 } 235 if (bit2_createTimePresent && offset + 4 <= len) { 236 createTime = new ZipLong(data, offset); 237 offset += 4; // NOSONAR - assignment as documentation 238 } 239 } 240 241 /** 242 * Doesn't do anything special since this class always uses the 243 * same parsing logic for both central directory and local file data. 244 */ 245 @Override 246 public void parseFromCentralDirectoryData( 247 final byte[] buffer, final int offset, final int length 248 ) throws ZipException { 249 reset(); 250 parseFromLocalFileData(buffer, offset, length); 251 } 252 253 /** 254 * Reset state back to newly constructed state. Helps us make sure 255 * parse() calls always generate clean results. 256 */ 257 private void reset() { 258 setFlags((byte) 0); 259 this.modifyTime = null; 260 this.accessTime = null; 261 this.createTime = null; 262 } 263 264 /** 265 * Sets flags byte. The flags byte tells us which of the 266 * three datestamp fields are present in the data: 267 * <pre> 268 * bit0 - modify time 269 * bit1 - access time 270 * bit2 - create time 271 * </pre> 272 * Only first 3 bits of flags are used according to the 273 * latest version of the spec (December 2012). 274 * 275 * @param flags flags byte indicating which of the 276 * three datestamp fields are present. 277 */ 278 public void setFlags(final byte flags) { 279 this.flags = flags; 280 this.bit0_modifyTimePresent = (flags & MODIFY_TIME_BIT) == MODIFY_TIME_BIT; 281 this.bit1_accessTimePresent = (flags & ACCESS_TIME_BIT) == ACCESS_TIME_BIT; 282 this.bit2_createTimePresent = (flags & CREATE_TIME_BIT) == CREATE_TIME_BIT; 283 } 284 285 /** 286 * Gets flags byte. The flags byte tells us which of the 287 * three datestamp fields are present in the data: 288 * <pre> 289 * bit0 - modify time 290 * bit1 - access time 291 * bit2 - create time 292 * </pre> 293 * Only first 3 bits of flags are used according to the 294 * latest version of the spec (December 2012). 295 * 296 * @return flags byte indicating which of the 297 * three datestamp fields are present. 298 */ 299 public byte getFlags() { return flags; } 300 301 /** 302 * Returns whether bit0 of the flags byte is set or not, 303 * which should correspond to the presence or absence of 304 * a modify timestamp in this particular zip entry. 305 * 306 * @return true if bit0 of the flags byte is set. 307 */ 308 public boolean isBit0_modifyTimePresent() { return bit0_modifyTimePresent; } 309 310 /** 311 * Returns whether bit1 of the flags byte is set or not, 312 * which should correspond to the presence or absence of 313 * a "last access" timestamp in this particular zip entry. 314 * 315 * @return true if bit1 of the flags byte is set. 316 */ 317 public boolean isBit1_accessTimePresent() { return bit1_accessTimePresent; } 318 319 /** 320 * Returns whether bit2 of the flags byte is set or not, 321 * which should correspond to the presence or absence of 322 * a create timestamp in this particular zip entry. 323 * 324 * @return true if bit2 of the flags byte is set. 325 */ 326 public boolean isBit2_createTimePresent() { return bit2_createTimePresent; } 327 328 /** 329 * Returns the modify time (seconds since epoch) of this zip entry 330 * as a ZipLong object, or null if no such timestamp exists in the 331 * zip entry. 332 * 333 * @return modify time (seconds since epoch) or null. 334 */ 335 public ZipLong getModifyTime() { return modifyTime; } 336 337 /** 338 * Returns the access time (seconds since epoch) of this zip entry 339 * as a ZipLong object, or null if no such timestamp exists in the 340 * zip entry. 341 * 342 * @return access time (seconds since epoch) or null. 343 */ 344 public ZipLong getAccessTime() { return accessTime; } 345 346 /** 347 * <p> 348 * Returns the create time (seconds since epoch) of this zip entry 349 * as a ZipLong object, or null if no such timestamp exists in the 350 * zip entry. 351 * </p><p> 352 * Note: modern linux file systems (e.g., ext2) 353 * do not appear to store a "create time" value, and so 354 * it's usually omitted altogether in the zip extra 355 * field. Perhaps other unix systems track this. 356 * 357 * @return create time (seconds since epoch) or null. 358 */ 359 public ZipLong getCreateTime() { return createTime; } 360 361 /** 362 * Returns the modify time as a java.util.Date 363 * of this zip entry, or null if no such timestamp exists in the zip entry. 364 * The milliseconds are always zeroed out, since the underlying data 365 * offers only per-second precision. 366 * 367 * @return modify time as java.util.Date or null. 368 */ 369 public Date getModifyJavaTime() { 370 return zipLongToDate(modifyTime); 371 } 372 373 /** 374 * Returns the access time as a java.util.Date 375 * of this zip entry, or null if no such timestamp exists in the zip entry. 376 * The milliseconds are always zeroed out, since the underlying data 377 * offers only per-second precision. 378 * 379 * @return access time as java.util.Date or null. 380 */ 381 public Date getAccessJavaTime() { 382 return zipLongToDate(accessTime); 383 } 384 385 /** 386 * <p> 387 * Returns the create time as a a java.util.Date 388 * of this zip entry, or null if no such timestamp exists in the zip entry. 389 * The milliseconds are always zeroed out, since the underlying data 390 * offers only per-second precision. 391 * </p><p> 392 * Note: modern linux file systems (e.g., ext2) 393 * do not appear to store a "create time" value, and so 394 * it's usually omitted altogether in the zip extra 395 * field. Perhaps other unix systems track this. 396 * 397 * @return create time as java.util.Date or null. 398 */ 399 public Date getCreateJavaTime() { 400 return zipLongToDate(createTime); 401 } 402 403 /** 404 * <p> 405 * Sets the modify time (seconds since epoch) of this zip entry 406 * using a ZipLong object. 407 * </p><p> 408 * Note: the setters for flags and timestamps are decoupled. 409 * Even if the timestamp is not-null, it will only be written 410 * out if the corresponding bit in the flags is also set. 411 * </p> 412 * 413 * @param l ZipLong of the modify time (seconds per epoch) 414 */ 415 public void setModifyTime(final ZipLong l) { 416 bit0_modifyTimePresent = l != null; 417 flags = (byte) (l != null ? (flags | MODIFY_TIME_BIT) 418 : (flags & ~MODIFY_TIME_BIT)); 419 this.modifyTime = l; 420 } 421 422 /** 423 * <p> 424 * Sets the access time (seconds since epoch) of this zip entry 425 * using a ZipLong object 426 * </p><p> 427 * Note: the setters for flags and timestamps are decoupled. 428 * Even if the timestamp is not-null, it will only be written 429 * out if the corresponding bit in the flags is also set. 430 * </p> 431 * 432 * @param l ZipLong of the access time (seconds per epoch) 433 */ 434 public void setAccessTime(final ZipLong l) { 435 bit1_accessTimePresent = l != null; 436 flags = (byte) (l != null ? (flags | ACCESS_TIME_BIT) 437 : (flags & ~ACCESS_TIME_BIT)); 438 this.accessTime = l; 439 } 440 441 /** 442 * <p> 443 * Sets the create time (seconds since epoch) of this zip entry 444 * using a ZipLong object 445 * </p><p> 446 * Note: the setters for flags and timestamps are decoupled. 447 * Even if the timestamp is not-null, it will only be written 448 * out if the corresponding bit in the flags is also set. 449 * </p> 450 * 451 * @param l ZipLong of the create time (seconds per epoch) 452 */ 453 public void setCreateTime(final ZipLong l) { 454 bit2_createTimePresent = l != null; 455 flags = (byte) (l != null ? (flags | CREATE_TIME_BIT) 456 : (flags & ~CREATE_TIME_BIT)); 457 this.createTime = l; 458 } 459 460 /** 461 * <p> 462 * Sets the modify time as a java.util.Date 463 * of this zip entry. Supplied value is truncated to per-second 464 * precision (milliseconds zeroed-out). 465 * </p><p> 466 * Note: the setters for flags and timestamps are decoupled. 467 * Even if the timestamp is not-null, it will only be written 468 * out if the corresponding bit in the flags is also set. 469 * </p> 470 * 471 * @param d modify time as java.util.Date 472 */ 473 public void setModifyJavaTime(final Date d) { setModifyTime(dateToZipLong(d)); } 474 475 /** 476 * <p> 477 * Sets the access time as a java.util.Date 478 * of this zip entry. Supplied value is truncated to per-second 479 * precision (milliseconds zeroed-out). 480 * </p><p> 481 * Note: the setters for flags and timestamps are decoupled. 482 * Even if the timestamp is not-null, it will only be written 483 * out if the corresponding bit in the flags is also set. 484 * </p> 485 * 486 * @param d access time as java.util.Date 487 */ 488 public void setAccessJavaTime(final Date d) { setAccessTime(dateToZipLong(d)); } 489 490 /** 491 * <p> 492 * Sets the create time as a java.util.Date 493 * of this zip entry. Supplied value is truncated to per-second 494 * precision (milliseconds zeroed-out). 495 * </p><p> 496 * Note: the setters for flags and timestamps are decoupled. 497 * Even if the timestamp is not-null, it will only be written 498 * out if the corresponding bit in the flags is also set. 499 * </p> 500 * 501 * @param d create time as java.util.Date 502 */ 503 public void setCreateJavaTime(final Date d) { setCreateTime(dateToZipLong(d)); } 504 505 /** 506 * Utility method converts java.util.Date (milliseconds since epoch) 507 * into a ZipLong (seconds since epoch). 508 * <p/> 509 * Also makes sure the converted ZipLong is not too big to fit 510 * in 32 unsigned bits. 511 * 512 * @param d java.util.Date to convert to ZipLong 513 * @return ZipLong 514 */ 515 private static ZipLong dateToZipLong(final Date d) { 516 if (d == null) { return null; } 517 518 return unixTimeToZipLong(d.getTime() / 1000); 519 } 520 521 /** 522 * Returns a String representation of this class useful for 523 * debugging purposes. 524 * 525 * @return A String representation of this class useful for 526 * debugging purposes. 527 */ 528 @Override 529 public String toString() { 530 final StringBuilder buf = new StringBuilder(); 531 buf.append("0x5455 Zip Extra Field: Flags="); 532 buf.append(Integer.toBinaryString(ZipUtil.unsignedIntToSignedByte(flags))).append(" "); 533 if (bit0_modifyTimePresent && modifyTime != null) { 534 final Date m = getModifyJavaTime(); 535 buf.append(" Modify:[").append(m).append("] "); 536 } 537 if (bit1_accessTimePresent && accessTime != null) { 538 final Date a = getAccessJavaTime(); 539 buf.append(" Access:[").append(a).append("] "); 540 } 541 if (bit2_createTimePresent && createTime != null) { 542 final Date c = getCreateJavaTime(); 543 buf.append(" Create:[").append(c).append("] "); 544 } 545 return buf.toString(); 546 } 547 548 @Override 549 public Object clone() throws CloneNotSupportedException { 550 return super.clone(); 551 } 552 553 @Override 554 public boolean equals(final Object o) { 555 if (o instanceof X5455_ExtendedTimestamp) { 556 final X5455_ExtendedTimestamp xf = (X5455_ExtendedTimestamp) o; 557 558 // The ZipLong==ZipLong clauses handle the cases where both are null. 559 // and only last 3 bits of flags matter. 560 return ((flags & 0x07) == (xf.flags & 0x07)) && 561 (modifyTime == xf.modifyTime || (modifyTime != null && modifyTime.equals(xf.modifyTime))) && 562 (accessTime == xf.accessTime || (accessTime != null && accessTime.equals(xf.accessTime))) && 563 (createTime == xf.createTime || (createTime != null && createTime.equals(xf.createTime))); 564 } 565 return false; 566 } 567 568 @Override 569 public int hashCode() { 570 int hc = (-123 * (flags & 0x07)); // only last 3 bits of flags matter 571 if (modifyTime != null) { 572 hc ^= modifyTime.hashCode(); 573 } 574 if (accessTime != null) { 575 // Since accessTime is often same as modifyTime, 576 // this prevents them from XOR negating each other. 577 hc ^= Integer.rotateLeft(accessTime.hashCode(), 11); 578 } 579 if (createTime != null) { 580 hc ^= Integer.rotateLeft(createTime.hashCode(), 22); 581 } 582 return hc; 583 } 584 585 private static Date zipLongToDate(ZipLong unixTime) { 586 return unixTime != null ? new Date(unixTime.getIntValue() * 1000L) : null; 587 } 588 589 private static ZipLong unixTimeToZipLong(long l) { 590 if (l < Integer.MIN_VALUE || l > Integer.MAX_VALUE) { 591 throw new IllegalArgumentException("X5455 timestamps must fit in a signed 32 bit integer: " + l); 592 } 593 return new ZipLong(l); 594 } 595 596}