1 /*
2 * Copyright (c) 1997, 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.io;
27
28 import java.nio.file.*;
29 import java.security.*;
30 import java.util.Enumeration;
31 import java.util.Objects;
32 import java.util.StringJoiner;
33 import java.util.Vector;
34 import java.util.concurrent.ConcurrentHashMap;
35
36 import jdk.internal.access.JavaIOFilePermissionAccess;
37 import jdk.internal.access.SharedSecrets;
38 import sun.nio.fs.DefaultFileSystemProvider;
39 import sun.security.action.GetPropertyAction;
40 import sun.security.util.FilePermCompat;
41 import sun.security.util.SecurityConstants;
42
43 /**
44 * This class represents access to a file or directory. A FilePermission consists
45 * of a pathname and a set of actions valid for that pathname.
46 * <P>
47 * Pathname is the pathname of the file or directory granted the specified
48 * actions. A pathname that ends in "/*" (where "/" is
49 * the file separator character, <code>File.separatorChar</code>) indicates
50 * all the files and directories contained in that directory. A pathname
51 * that ends with "/-" indicates (recursively) all files
52 * and subdirectories contained in that directory. Such a pathname is called
53 * a wildcard pathname. Otherwise, it's a simple pathname.
54 * <P>
55 * A pathname consisting of the special token {@literal "<<ALL FILES>>"}
56 * matches <b>any</b> file.
57 * <P>
58 * Note: A pathname consisting of a single "*" indicates all the files
59 * in the current directory, while a pathname consisting of a single "-"
60 * indicates all the files in the current directory and
61 * (recursively) all files and subdirectories contained in the current
62 * directory.
63 * <P>
64 * The actions to be granted are passed to the constructor in a string containing
65 * a list of one or more comma-separated keywords. The possible keywords are
66 * "read", "write", "execute", "delete", and "readlink". Their meaning is
67 * defined as follows:
68 *
69 * <DL>
70 * <DT> read <DD> read permission
71 * <DT> write <DD> write permission
72 * <DT> execute
73 * <DD> execute permission. Allows <code>Runtime.exec</code> to
74 * be called. Corresponds to <code>SecurityManager.checkExec</code>.
75 * <DT> delete
76 * <DD> delete permission. Allows <code>File.delete</code> to
77 * be called. Corresponds to <code>SecurityManager.checkDelete</code>.
78 * <DT> readlink
79 * <DD> read link permission. Allows the target of a
80 * <a href="../nio/file/package-summary.html#links">symbolic link</a>
81 * to be read by invoking the {@link java.nio.file.Files#readSymbolicLink
82 * readSymbolicLink } method.
83 * </DL>
84 * <P>
85 * The actions string is converted to lowercase before processing.
86 * <P>
87 * Be careful when granting FilePermissions. Think about the implications
88 * of granting read and especially write access to various files and
89 * directories. The {@literal "<<ALL FILES>>"} permission with write action is
90 * especially dangerous. This grants permission to write to the entire
91 * file system. One thing this effectively allows is replacement of the
92 * system binary, including the JVM runtime environment.
93 * <P>
94 * Please note: Code can always read a file from the same
95 * directory it's in (or a subdirectory of that directory); it does not
96 * need explicit permission to do so.
97 *
98 * @see java.security.Permission
99 * @see java.security.Permissions
100 * @see java.security.PermissionCollection
101 *
102 *
103 * @author Marianne Mueller
104 * @author Roland Schemers
105 * @since 1.2
106 *
107 * @serial exclude
108 */
109
110 public final class FilePermission extends Permission implements Serializable {
111
112 /**
113 * Execute action.
114 */
115 private static final int EXECUTE = 0x1;
116 /**
117 * Write action.
118 */
119 private static final int WRITE = 0x2;
120 /**
121 * Read action.
122 */
123 private static final int READ = 0x4;
124 /**
125 * Delete action.
126 */
127 private static final int DELETE = 0x8;
128 /**
129 * Read link action.
130 */
131 private static final int READLINK = 0x10;
132
133 /**
134 * All actions (read,write,execute,delete,readlink)
135 */
136 private static final int ALL = READ|WRITE|EXECUTE|DELETE|READLINK;
137 /**
138 * No actions.
139 */
140 private static final int NONE = 0x0;
141
142 // the actions mask
143 private transient int mask;
144
145 // does path indicate a directory? (wildcard or recursive)
146 private transient boolean directory;
147
148 // is it a recursive directory specification?
149 private transient boolean recursive;
150
151 /**
152 * the actions string.
153 *
154 * @serial
155 */
156 private String actions; // Left null as long as possible, then
157 // created and re-used in the getAction function.
158
159 // canonicalized dir path. used by the "old" behavior (nb == false).
160 // In the case of directories, it is the name "/blah/*" or "/blah/-"
161 // without the last character (the "*" or "-").
162
163 private transient String cpath;
164
165 // Following fields used by the "new" behavior (nb == true), in which
166 // input path is not canonicalized. For compatibility (so that granting
167 // FilePermission on "x" allows reading "`pwd`/x", an alternative path
168 // can be added so that both can be used in an implies() check. Please note
169 // the alternative path only deals with absolute/relative path, and does
170 // not deal with symlink/target.
171
172 private transient Path npath; // normalized dir path.
173 private transient Path npath2; // alternative normalized dir path.
174 private transient boolean allFiles; // whether this is <<ALL FILES>>
175 private transient boolean invalid; // whether input path is invalid
176
177 // static Strings used by init(int mask)
178 private static final char RECURSIVE_CHAR = '-';
179 private static final char WILD_CHAR = '*';
180
181 // public String toString() {
182 // StringBuffer sb = new StringBuffer();
183 // sb.append("*** FilePermission on " + getName() + " ***");
184 // for (Field f : FilePermission.class.getDeclaredFields()) {
185 // if (!Modifier.isStatic(f.getModifiers())) {
186 // try {
187 // sb.append(f.getName() + " = " + f.get(this));
188 // } catch (Exception e) {
189 // sb.append(f.getName() + " = " + e.toString());
190 // }
191 // sb.append('\n');
192 // }
193 // }
194 // sb.append("***\n");
195 // return sb.toString();
196 // }
197
198 private static final long serialVersionUID = 7930732926638008763L;
199
200 /**
201 * Always use the builtin system-default file system, in case the
202 * java.nio.file.spi.DefaultFileSystemProvider system property is set.
203 */
204 private static final java.nio.file.FileSystem builtInFS =
205 DefaultFileSystemProvider.theFileSystem();
206
207 private static final Path here = builtInFS.getPath(
208 GetPropertyAction.privilegedGetProperty("user.dir"));
209
210 private static final Path EMPTY_PATH = builtInFS.getPath("");
211 private static final Path DASH_PATH = builtInFS.getPath("-");
212 private static final Path DOTDOT_PATH = builtInFS.getPath("..");
213
214 /**
215 * A private constructor that clones some and updates some,
216 * always with a different name.
217 * @param input
218 */
219 private FilePermission(String name,
220 FilePermission input,
221 Path npath,
222 Path npath2,
223 int mask,
224 String actions) {
225 super(name);
226 // Customizables
227 this.npath = npath;
228 this.npath2 = npath2;
229 this.actions = actions;
230 this.mask = mask;
231 // Cloneds
232 this.allFiles = input.allFiles;
233 this.invalid = input.invalid;
234 this.recursive = input.recursive;
235 this.directory = input.directory;
236 this.cpath = input.cpath;
237 }
238
239 /**
240 * Returns the alternative path as a Path object, i.e. absolute path
241 * for a relative one, or vice versa.
242 *
243 * @param in a real path w/o "-" or "*" at the end, and not <<ALL FILES>>.
244 * @return the alternative path, or null if cannot find one.
245 */
246 private static Path altPath(Path in) {
247 try {
248 if (!in.isAbsolute()) {
249 return here.resolve(in).normalize();
250 } else {
251 return here.relativize(in).normalize();
252 }
253 } catch (IllegalArgumentException e) {
254 return null;
255 }
256 }
257
258 static {
259 SharedSecrets.setJavaIOFilePermissionAccess(
260 /**
261 * Creates FilePermission objects with special internals.
262 * See {@link FilePermCompat#newPermPlusAltPath(Permission)} and
263 * {@link FilePermCompat#newPermUsingAltPath(Permission)}.
264 */
265 new JavaIOFilePermissionAccess() {
266 public FilePermission newPermPlusAltPath(FilePermission input) {
267 if (!input.invalid && input.npath2 == null && !input.allFiles) {
268 Path npath2 = altPath(input.npath);
269 if (npath2 != null) {
270 // Please note the name of the new permission is
271 // different than the original so that when one is
272 // added to a FilePermissionCollection it will not
273 // be merged with the original one.
274 return new FilePermission(input.getName() + "#plus",
275 input,
276 input.npath,
277 npath2,
278 input.mask,
279 input.actions);
280 }
281 }
282 return input;
283 }
284 public FilePermission newPermUsingAltPath(FilePermission input) {
285 if (!input.invalid && !input.allFiles) {
286 Path npath2 = altPath(input.npath);
287 if (npath2 != null) {
288 // New name, see above.
289 return new FilePermission(input.getName() + "#using",
290 input,
291 npath2,
292 null,
293 input.mask,
294 input.actions);
295 }
296 }
297 return null;
298 }
299 }
300 );
301 }
302
303 /**
304 * initialize a FilePermission object. Common to all constructors.
305 * Also called during de-serialization.
306 *
307 * @param mask the actions mask to use.
308 *
309 */
310 private void init(int mask) {
311 if ((mask & ALL) != mask)
312 throw new IllegalArgumentException("invalid actions mask");
313
314 if (mask == NONE)
315 throw new IllegalArgumentException("invalid actions mask");
316
317 if (FilePermCompat.nb) {
318 String name = getName();
319
320 if (name == null)
321 throw new NullPointerException("name can't be null");
322
323 this.mask = mask;
324
325 if (name.equals("<<ALL FILES>>")) {
326 allFiles = true;
327 npath = EMPTY_PATH;
328 // other fields remain default
329 return;
330 }
331
332 boolean rememberStar = false;
333 if (name.endsWith("*")) {
334 rememberStar = true;
335 recursive = false;
336 name = name.substring(0, name.length()-1) + "-";
337 }
338
339 try {
340 // new File() can "normalize" some name, for example, "/C:/X" on
341 // Windows. Some JDK codes generate such illegal names.
342 npath = builtInFS.getPath(new File(name).getPath())
343 .normalize();
344 // lastName should always be non-null now
345 Path lastName = npath.getFileName();
346 if (lastName != null && lastName.equals(DASH_PATH)) {
347 directory = true;
348 recursive = !rememberStar;
349 npath = npath.getParent();
350 }
351 if (npath == null) {
352 npath = EMPTY_PATH;
353 }
354 invalid = false;
355 } catch (InvalidPathException ipe) {
356 // Still invalid. For compatibility reason, accept it
357 // but make this permission useless.
358 npath = builtInFS.getPath("-u-s-e-l-e-s-s-");
359 invalid = true;
360 }
361
362 } else {
363 if ((cpath = getName()) == null)
364 throw new NullPointerException("name can't be null");
365
366 this.mask = mask;
367
368 if (cpath.equals("<<ALL FILES>>")) {
369 directory = true;
370 recursive = true;
371 cpath = "";
372 return;
373 }
374
375 // store only the canonical cpath if possible
376 cpath = AccessController.doPrivileged(new PrivilegedAction<>() {
377 public String run() {
378 try {
379 String path = cpath;
380 if (cpath.endsWith("*")) {
381 // call getCanonicalPath with a path with wildcard character
382 // replaced to avoid calling it with paths that are
383 // intended to match all entries in a directory
384 path = path.substring(0, path.length() - 1) + "-";
385 path = new File(path).getCanonicalPath();
386 return path.substring(0, path.length() - 1) + "*";
387 } else {
388 return new File(path).getCanonicalPath();
389 }
390 } catch (IOException ioe) {
391 return cpath;
392 }
393 }
394 });
395
396 int len = cpath.length();
397 char last = ((len > 0) ? cpath.charAt(len - 1) : 0);
398
399 if (last == RECURSIVE_CHAR &&
400 cpath.charAt(len - 2) == File.separatorChar) {
401 directory = true;
402 recursive = true;
403 cpath = cpath.substring(0, --len);
404 } else if (last == WILD_CHAR &&
405 cpath.charAt(len - 2) == File.separatorChar) {
406 directory = true;
407 //recursive = false;
408 cpath = cpath.substring(0, --len);
409 } else {
410 // overkill since they are initialized to false, but
411 // commented out here to remind us...
412 //directory = false;
413 //recursive = false;
414 }
415
416 // XXX: at this point the path should be absolute. die if it isn't?
417 }
418 }
419
420 /**
421 * Creates a new FilePermission object with the specified actions.
422 * <i>path</i> is the pathname of a file or directory, and <i>actions</i>
423 * contains a comma-separated list of the desired actions granted on the
424 * file or directory. Possible actions are
425 * "read", "write", "execute", "delete", and "readlink".
426 *
427 * <p>A pathname that ends in "/*" (where "/" is
428 * the file separator character, <code>File.separatorChar</code>)
429 * indicates all the files and directories contained in that directory.
430 * A pathname that ends with "/-" indicates (recursively) all files and
431 * subdirectories contained in that directory. The special pathname
432 * {@literal "<<ALL FILES>>"} matches any file.
433 *
434 * <p>A pathname consisting of a single "*" indicates all the files
435 * in the current directory, while a pathname consisting of a single "-"
436 * indicates all the files in the current directory and
437 * (recursively) all files and subdirectories contained in the current
438 * directory.
439 *
440 * <p>A pathname containing an empty string represents an empty path.
441 *
442 * @implNote In this implementation, the
443 * {@code jdk.io.permissionsUseCanonicalPath} system property dictates how
444 * the {@code path} argument is processed and stored.
445 * <P>
446 * If the value of the system property is set to {@code true}, {@code path}
447 * is canonicalized and stored as a String object named {@code cpath}.
448 * This means a relative path is converted to an absolute path, a Windows
449 * DOS-style 8.3 path is expanded to a long path, and a symbolic link is
450 * resolved to its target, etc.
451 * <P>
452 * If the value of the system property is set to {@code false}, {@code path}
453 * is converted to a {@link java.nio.file.Path} object named {@code npath}
454 * after {@link Path#normalize() normalization}. No canonicalization is
455 * performed which means the underlying file system is not accessed.
456 * If an {@link InvalidPathException} is thrown during the conversion,
457 * this {@code FilePermission} will be labeled as invalid.
458 * <P>
459 * In either case, the "*" or "-" character at the end of a wildcard
460 * {@code path} is removed before canonicalization or normalization.
461 * It is stored in a separate wildcard flag field.
462 * <P>
463 * The default value of the {@code jdk.io.permissionsUseCanonicalPath}
464 * system property is {@code false} in this implementation.
465 *
466 * @param path the pathname of the file/directory.
467 * @param actions the action string.
468 *
469 * @throws IllegalArgumentException
470 * If actions is <code>null</code>, empty or contains an action
471 * other than the specified possible actions.
472 */
473 public FilePermission(String path, String actions) {
474 super(path);
475 init(getMask(actions));
476 }
477
478 /**
479 * Creates a new FilePermission object using an action mask.
480 * More efficient than the FilePermission(String, String) constructor.
481 * Can be used from within
482 * code that needs to create a FilePermission object to pass into the
483 * <code>implies</code> method.
484 *
485 * @param path the pathname of the file/directory.
486 * @param mask the action mask to use.
487 */
488 // package private for use by the FilePermissionCollection add method
489 FilePermission(String path, int mask) {
490 super(path);
491 init(mask);
492 }
493
494 /**
495 * Checks if this FilePermission object "implies" the specified permission.
496 * <P>
497 * More specifically, this method returns true if:
498 * <ul>
499 * <li> <i>p</i> is an instanceof FilePermission,
500 * <li> <i>p</i>'s actions are a proper subset of this
501 * object's actions, and
502 * <li> <i>p</i>'s pathname is implied by this object's
503 * pathname. For example, "/tmp/*" implies "/tmp/foo", since
504 * "/tmp/*" encompasses all files in the "/tmp" directory,
505 * including the one named "foo".
506 * </ul>
507 * <P>
508 * Precisely, a simple pathname implies another simple pathname
509 * if and only if they are equal. A simple pathname never implies
510 * a wildcard pathname. A wildcard pathname implies another wildcard
511 * pathname if and only if all simple pathnames implied by the latter
512 * are implied by the former. A wildcard pathname implies a simple
513 * pathname if and only if
514 * <ul>
515 * <li>if the wildcard flag is "*", the simple pathname's path
516 * must be right inside the wildcard pathname's path.
517 * <li>if the wildcard flag is "-", the simple pathname's path
518 * must be recursively inside the wildcard pathname's path.
519 * </ul>
520 * <P>
521 * {@literal "<<ALL FILES>>"} implies every other pathname. No pathname,
522 * except for {@literal "<<ALL FILES>>"} itself, implies
523 * {@literal "<<ALL FILES>>"}.
524 *
525 * @implNote
526 * If {@code jdk.io.permissionsUseCanonicalPath} is {@code true}, a
527 * simple {@code cpath} is inside a wildcard {@code cpath} if and only if
528 * after removing the base name (the last name in the pathname's name
529 * sequence) from the former the remaining part equals to the latter,
530 * a simple {@code cpath} is recursively inside a wildcard {@code cpath}
531 * if and only if the former starts with the latter.
532 * <p>
533 * If {@code jdk.io.permissionsUseCanonicalPath} is {@code false}, a
534 * simple {@code npath} is inside a wildcard {@code npath} if and only if
535 * {@code simple_npath.relativize(wildcard_npath)} is exactly "..",
536 * a simple {@code npath} is recursively inside a wildcard {@code npath}
537 * if and only if {@code simple_npath.relativize(wildcard_npath)} is a
538 * series of one or more "..". This means "/-" implies "/foo" but not "foo".
539 * <p>
540 * An invalid {@code FilePermission} does not imply any object except for
541 * itself. An invalid {@code FilePermission} is not implied by any object
542 * except for itself or a {@code FilePermission} on
543 * {@literal "<<ALL FILES>>"} whose actions is a superset of this
544 * invalid {@code FilePermission}. Even if two {@code FilePermission}
545 * are created with the same invalid path, one does not imply the other.
546 *
547 * @param p the permission to check against.
548 *
549 * @return <code>true</code> if the specified permission is not
550 * <code>null</code> and is implied by this object,
551 * <code>false</code> otherwise.
552 */
553 @Override
554 public boolean implies(Permission p) {
555 if (!(p instanceof FilePermission))
556 return false;
557
558 FilePermission that = (FilePermission) p;
559
560 // we get the effective mask. i.e., the "and" of this and that.
561 // They must be equal to that.mask for implies to return true.
562
563 return ((this.mask & that.mask) == that.mask) && impliesIgnoreMask(that);
564 }
565
566 /**
567 * Checks if the Permission's actions are a proper subset of the
568 * this object's actions. Returns the effective mask iff the
569 * this FilePermission's path also implies that FilePermission's path.
570 *
571 * @param that the FilePermission to check against.
572 * @return the effective mask
573 */
574 boolean impliesIgnoreMask(FilePermission that) {
575 if (FilePermCompat.nb) {
576 if (this == that) {
577 return true;
578 }
579 if (allFiles) {
580 return true;
581 }
582 if (this.invalid || that.invalid) {
583 return false;
584 }
585 if (that.allFiles) {
586 return false;
587 }
588 // Left at least same level of wildness as right
589 if ((this.recursive && that.recursive) != that.recursive
590 || (this.directory && that.directory) != that.directory) {
591 return false;
592 }
593 // Same npath is good as long as both or neither are directories
594 if (this.npath.equals(that.npath)
595 && this.directory == that.directory) {
596 return true;
597 }
598 int diff = containsPath(this.npath, that.npath);
599 // Right inside left is good if recursive
600 if (diff >= 1 && recursive) {
601 return true;
602 }
603 // Right right inside left if it is element in set
604 if (diff == 1 && directory && !that.directory) {
605 return true;
606 }
607
608 // Hack: if a npath2 field exists, apply the same checks
609 // on it as a fallback.
610 if (this.npath2 != null) {
611 if (this.npath2.equals(that.npath)
612 && this.directory == that.directory) {
613 return true;
614 }
615 diff = containsPath(this.npath2, that.npath);
616 if (diff >= 1 && recursive) {
617 return true;
618 }
619 if (diff == 1 && directory && !that.directory) {
620 return true;
621 }
622 }
623
624 return false;
625 } else {
626 if (this.directory) {
627 if (this.recursive) {
628 // make sure that.path is longer then path so
629 // something like /foo/- does not imply /foo
630 if (that.directory) {
631 return (that.cpath.length() >= this.cpath.length()) &&
632 that.cpath.startsWith(this.cpath);
633 } else {
634 return ((that.cpath.length() > this.cpath.length()) &&
635 that.cpath.startsWith(this.cpath));
636 }
637 } else {
638 if (that.directory) {
639 // if the permission passed in is a directory
640 // specification, make sure that a non-recursive
641 // permission (i.e., this object) can't imply a recursive
642 // permission.
643 if (that.recursive)
644 return false;
645 else
646 return (this.cpath.equals(that.cpath));
647 } else {
648 int last = that.cpath.lastIndexOf(File.separatorChar);
649 if (last == -1)
650 return false;
651 else {
652 // this.cpath.equals(that.cpath.substring(0, last+1));
653 // Use regionMatches to avoid creating new string
654 return (this.cpath.length() == (last + 1)) &&
655 this.cpath.regionMatches(0, that.cpath, 0, last + 1);
656 }
657 }
658 }
659 } else if (that.directory) {
660 // if this is NOT recursive/wildcarded,
661 // do not let it imply a recursive/wildcarded permission
662 return false;
663 } else {
664 return (this.cpath.equals(that.cpath));
665 }
666 }
667 }
668
669 /**
670 * Returns the depth between an outer path p1 and an inner path p2. -1
671 * is returned if
672 *
673 * - p1 does not contains p2.
674 * - this is not decidable. For example, p1="../x", p2="y".
675 * - the depth is not decidable. For example, p1="/", p2="x".
676 *
677 * This method can return 2 if the depth is greater than 2.
678 *
679 * @param p1 the expected outer path, normalized
680 * @param p2 the expected inner path, normalized
681 * @return the depth in between
682 */
683 private static int containsPath(Path p1, Path p2) {
684
685 // Two paths must have the same root. For example,
686 // there is no contains relation between any two of
687 // "/x", "x", "C:/x", "C:x", and "//host/share/x".
688 if (!Objects.equals(p1.getRoot(), p2.getRoot())) {
689 return -1;
690 }
691
692 // Empty path (i.e. "." or "") is a strange beast,
693 // because its getNameCount()==1 but getName(0) is null.
694 // It's better to deal with it separately.
695 if (p1.equals(EMPTY_PATH)) {
696 if (p2.equals(EMPTY_PATH)) {
697 return 0;
698 } else if (p2.getName(0).equals(DOTDOT_PATH)) {
699 // "." contains p2 iff p2 has no "..". Since
700 // a normalized path can only have 0 or more
701 // ".." at the beginning. We only need to look
702 // at the head.
703 return -1;
704 } else {
705 // and the distance is p2's name count. i.e.
706 // 3 between "." and "a/b/c".
707 return p2.getNameCount();
708 }
709 } else if (p2.equals(EMPTY_PATH)) {
710 int c1 = p1.getNameCount();
711 if (!p1.getName(c1 - 1).equals(DOTDOT_PATH)) {
712 // "." is inside p1 iff p1 is 1 or more "..".
713 // For the same reason above, we only need to
714 // look at the tail.
715 return -1;
716 }
717 // and the distance is the count of ".."
718 return c1;
719 }
720
721 // Good. No more empty paths.
722
723 // Common heads are removed
724
725 int c1 = p1.getNameCount();
726 int c2 = p2.getNameCount();
727
728 int n = Math.min(c1, c2);
729 int i = 0;
730 while (i < n) {
731 if (!p1.getName(i).equals(p2.getName(i)))
732 break;
733 i++;
734 }
735
736 // for p1 containing p2, p1 must be 0-or-more "..",
737 // and p2 cannot have "..". For the same reason, we only
738 // check tail of p1 and head of p2.
739 if (i < c1 && !p1.getName(c1 - 1).equals(DOTDOT_PATH)) {
740 return -1;
741 }
742
743 if (i < c2 && p2.getName(i).equals(DOTDOT_PATH)) {
744 return -1;
745 }
746
747 // and the distance is the name counts added (after removing
748 // the common heads).
749
750 // For example: p1 = "../../..", p2 = "../a".
751 // After removing the common heads, they become "../.." and "a",
752 // and the distance is (3-1)+(2-1) = 3.
753 return c1 - i + c2 - i;
754 }
755
756 /**
757 * Checks two FilePermission objects for equality. Checks that <i>obj</i> is
758 * a FilePermission, and has the same pathname and actions as this object.
759 *
760 * @implNote More specifically, two pathnames are the same if and only if
761 * they have the same wildcard flag and their {@code cpath}
762 * (if {@code jdk.io.permissionsUseCanonicalPath} is {@code true}) or
763 * {@code npath} (if {@code jdk.io.permissionsUseCanonicalPath}
764 * is {@code false}) are equal. Or they are both {@literal "<<ALL FILES>>"}.
765 * <p>
766 * When {@code jdk.io.permissionsUseCanonicalPath} is {@code false}, an
767 * invalid {@code FilePermission} does not equal to any object except
768 * for itself, even if they are created using the same invalid path.
769 *
770 * @param obj the object we are testing for equality with this object.
771 * @return <code>true</code> if obj is a FilePermission, and has the same
772 * pathname and actions as this FilePermission object,
773 * <code>false</code> otherwise.
774 */
775 @Override
776 public boolean equals(Object obj) {
777 if (obj == this)
778 return true;
779
780 if (! (obj instanceof FilePermission))
781 return false;
782
783 FilePermission that = (FilePermission) obj;
784
785 if (FilePermCompat.nb) {
786 if (this.invalid || that.invalid) {
787 return false;
788 }
789 return (this.mask == that.mask) &&
790 (this.allFiles == that.allFiles) &&
791 this.npath.equals(that.npath) &&
792 Objects.equals(npath2, that.npath2) &&
793 (this.directory == that.directory) &&
794 (this.recursive == that.recursive);
795 } else {
796 return (this.mask == that.mask) &&
797 this.cpath.equals(that.cpath) &&
798 (this.directory == that.directory) &&
799 (this.recursive == that.recursive);
800 }
801 }
802
803 /**
804 * Returns the hash code value for this object.
805 *
806 * @return a hash code value for this object.
807 */
808 @Override
809 public int hashCode() {
810 if (FilePermCompat.nb) {
811 return Objects.hash(
812 mask, allFiles, directory, recursive, npath, npath2, invalid);
813 } else {
814 return 0;
815 }
816 }
817
818 /**
819 * Converts an actions String to an actions mask.
820 *
821 * @param actions the action string.
822 * @return the actions mask.
823 */
824 private static int getMask(String actions) {
825 int mask = NONE;
826
827 // Null action valid?
828 if (actions == null) {
829 return mask;
830 }
831
832 // Use object identity comparison against known-interned strings for
833 // performance benefit (these values are used heavily within the JDK).
834 if (actions == SecurityConstants.FILE_READ_ACTION) {
835 return READ;
836 } else if (actions == SecurityConstants.FILE_WRITE_ACTION) {
837 return WRITE;
838 } else if (actions == SecurityConstants.FILE_EXECUTE_ACTION) {
839 return EXECUTE;
840 } else if (actions == SecurityConstants.FILE_DELETE_ACTION) {
841 return DELETE;
842 } else if (actions == SecurityConstants.FILE_READLINK_ACTION) {
843 return READLINK;
844 }
845
846 char[] a = actions.toCharArray();
847
848 int i = a.length - 1;
849 if (i < 0)
850 return mask;
851
852 while (i != -1) {
853 char c;
854
855 // skip whitespace
856 while ((i!=-1) && ((c = a[i]) == ' ' ||
857 c == '\r' ||
858 c == '\n' ||
859 c == '\f' ||
860 c == '\t'))
861 i--;
862
863 // check for the known strings
864 int matchlen;
865
866 if (i >= 3 && (a[i-3] == 'r' || a[i-3] == 'R') &&
867 (a[i-2] == 'e' || a[i-2] == 'E') &&
868 (a[i-1] == 'a' || a[i-1] == 'A') &&
869 (a[i] == 'd' || a[i] == 'D'))
870 {
871 matchlen = 4;
872 mask |= READ;
873
874 } else if (i >= 4 && (a[i-4] == 'w' || a[i-4] == 'W') &&
875 (a[i-3] == 'r' || a[i-3] == 'R') &&
876 (a[i-2] == 'i' || a[i-2] == 'I') &&
877 (a[i-1] == 't' || a[i-1] == 'T') &&
878 (a[i] == 'e' || a[i] == 'E'))
879 {
880 matchlen = 5;
881 mask |= WRITE;
882
883 } else if (i >= 6 && (a[i-6] == 'e' || a[i-6] == 'E') &&
884 (a[i-5] == 'x' || a[i-5] == 'X') &&
885 (a[i-4] == 'e' || a[i-4] == 'E') &&
886 (a[i-3] == 'c' || a[i-3] == 'C') &&
887 (a[i-2] == 'u' || a[i-2] == 'U') &&
888 (a[i-1] == 't' || a[i-1] == 'T') &&
889 (a[i] == 'e' || a[i] == 'E'))
890 {
891 matchlen = 7;
892 mask |= EXECUTE;
893
894 } else if (i >= 5 && (a[i-5] == 'd' || a[i-5] == 'D') &&
895 (a[i-4] == 'e' || a[i-4] == 'E') &&
896 (a[i-3] == 'l' || a[i-3] == 'L') &&
897 (a[i-2] == 'e' || a[i-2] == 'E') &&
898 (a[i-1] == 't' || a[i-1] == 'T') &&
899 (a[i] == 'e' || a[i] == 'E'))
900 {
901 matchlen = 6;
902 mask |= DELETE;
903
904 } else if (i >= 7 && (a[i-7] == 'r' || a[i-7] == 'R') &&
905 (a[i-6] == 'e' || a[i-6] == 'E') &&
906 (a[i-5] == 'a' || a[i-5] == 'A') &&
907 (a[i-4] == 'd' || a[i-4] == 'D') &&
908 (a[i-3] == 'l' || a[i-3] == 'L') &&
909 (a[i-2] == 'i' || a[i-2] == 'I') &&
910 (a[i-1] == 'n' || a[i-1] == 'N') &&
911 (a[i] == 'k' || a[i] == 'K'))
912 {
913 matchlen = 8;
914 mask |= READLINK;
915
916 } else {
917 // parse error
918 throw new IllegalArgumentException(
919 "invalid permission: " + actions);
920 }
921
922 // make sure we didn't just match the tail of a word
923 // like "ackbarfaccept". Also, skip to the comma.
924 boolean seencomma = false;
925 while (i >= matchlen && !seencomma) {
926 switch(a[i-matchlen]) {
927 case ',':
928 seencomma = true;
929 break;
930 case ' ': case '\r': case '\n':
931 case '\f': case '\t':
932 break;
933 default:
934 throw new IllegalArgumentException(
935 "invalid permission: " + actions);
936 }
937 i--;
938 }
939
940 // point i at the location of the comma minus one (or -1).
941 i -= matchlen;
942 }
943
944 return mask;
945 }
946
947 /**
948 * Return the current action mask. Used by the FilePermissionCollection.
949 *
950 * @return the actions mask.
951 */
952 int getMask() {
953 return mask;
954 }
955
956 /**
957 * Return the canonical string representation of the actions.
958 * Always returns present actions in the following order:
959 * read, write, execute, delete, readlink.
960 *
961 * @return the canonical string representation of the actions.
962 */
963 private static String getActions(int mask) {
964 StringJoiner sj = new StringJoiner(",");
965
966 if ((mask & READ) == READ) {
967 sj.add("read");
968 }
969 if ((mask & WRITE) == WRITE) {
970 sj.add("write");
971 }
972 if ((mask & EXECUTE) == EXECUTE) {
973 sj.add("execute");
974 }
975 if ((mask & DELETE) == DELETE) {
976 sj.add("delete");
977 }
978 if ((mask & READLINK) == READLINK) {
979 sj.add("readlink");
980 }
981
982 return sj.toString();
983 }
984
985 /**
986 * Returns the "canonical string representation" of the actions.
987 * That is, this method always returns present actions in the following order:
988 * read, write, execute, delete, readlink. For example, if this FilePermission
989 * object allows both write and read actions, a call to <code>getActions</code>
990 * will return the string "read,write".
991 *
992 * @return the canonical string representation of the actions.
993 */
994 @Override
995 public String getActions() {
996 if (actions == null)
997 actions = getActions(this.mask);
998
999 return actions;
1000 }
1001
1002 /**
1003 * Returns a new PermissionCollection object for storing FilePermission
1004 * objects.
1005 * <p>
1006 * FilePermission objects must be stored in a manner that allows them
1007 * to be inserted into the collection in any order, but that also enables the
1008 * PermissionCollection <code>implies</code>
1009 * method to be implemented in an efficient (and consistent) manner.
1010 *
1011 * <p>For example, if you have two FilePermissions:
1012 * <OL>
1013 * <LI> <code>"/tmp/-", "read"</code>
1014 * <LI> <code>"/tmp/scratch/foo", "write"</code>
1015 * </OL>
1016 *
1017 * <p>and you are calling the <code>implies</code> method with the FilePermission:
1018 *
1019 * <pre>
1020 * "/tmp/scratch/foo", "read,write",
1021 * </pre>
1022 *
1023 * then the <code>implies</code> function must
1024 * take into account both the "/tmp/-" and "/tmp/scratch/foo"
1025 * permissions, so the effective permission is "read,write",
1026 * and <code>implies</code> returns true. The "implies" semantics for
1027 * FilePermissions are handled properly by the PermissionCollection object
1028 * returned by this <code>newPermissionCollection</code> method.
1029 *
1030 * @return a new PermissionCollection object suitable for storing
1031 * FilePermissions.
1032 */
1033 @Override
1034 public PermissionCollection newPermissionCollection() {
1035 return new FilePermissionCollection();
1036 }
1037
1038 /**
1039 * WriteObject is called to save the state of the FilePermission
1040 * to a stream. The actions are serialized, and the superclass
1041 * takes care of the name.
1042 */
1043 private void writeObject(ObjectOutputStream s)
1044 throws IOException
1045 {
1046 // Write out the actions. The superclass takes care of the name
1047 // call getActions to make sure actions field is initialized
1048 if (actions == null)
1049 getActions();
1050 s.defaultWriteObject();
1051 }
1052
1053 /**
1054 * readObject is called to restore the state of the FilePermission from
1055 * a stream.
1056 */
1057 private void readObject(ObjectInputStream s)
1058 throws IOException, ClassNotFoundException
1059 {
1060 // Read in the actions, then restore everything else by calling init.
1061 s.defaultReadObject();
1062 init(getMask(actions));
1063 }
1064
1065 /**
1066 * Create a cloned FilePermission with a different actions.
1067 * @param effective the new actions
1068 * @return a new object
1069 */
1070 FilePermission withNewActions(int effective) {
1071 return new FilePermission(this.getName(),
1072 this,
1073 this.npath,
1074 this.npath2,
1075 effective,
1076 null);
1077 }
1078 }
1079
1080 /**
1081 * A FilePermissionCollection stores a set of FilePermission permissions.
1082 * FilePermission objects
1083 * must be stored in a manner that allows them to be inserted in any
1084 * order, but enable the implies function to evaluate the implies
1085 * method.
1086 * For example, if you have two FilePermissions:
1087 * <OL>
1088 * <LI> "/tmp/-", "read"
1089 * <LI> "/tmp/scratch/foo", "write"
1090 * </OL>
1091 * And you are calling the implies function with the FilePermission:
1092 * "/tmp/scratch/foo", "read,write", then the implies function must
1093 * take into account both the /tmp/- and /tmp/scratch/foo
1094 * permissions, so the effective permission is "read,write".
1095 *
1096 * @see java.security.Permission
1097 * @see java.security.Permissions
1098 * @see java.security.PermissionCollection
1099 *
1100 *
1101 * @author Marianne Mueller
1102 * @author Roland Schemers
1103 *
1104 * @serial include
1105 *
1106 */
1107
1108 final class FilePermissionCollection extends PermissionCollection
1109 implements Serializable
1110 {
1111 // Not serialized; see serialization section at end of class
1112 private transient ConcurrentHashMap<String, Permission> perms;
1113
1114 /**
1115 * Create an empty FilePermissionCollection object.
1116 */
1117 public FilePermissionCollection() {
1118 perms = new ConcurrentHashMap<>();
1119 }
1120
1121 /**
1122 * Adds a permission to the FilePermissionCollection. The key for the hash is
1123 * permission.path.
1124 *
1125 * @param permission the Permission object to add.
1126 *
1127 * @exception IllegalArgumentException - if the permission is not a
1128 * FilePermission
1129 *
1130 * @exception SecurityException - if this FilePermissionCollection object
1131 * has been marked readonly
1132 */
1133 @Override
1134 public void add(Permission permission) {
1135 if (! (permission instanceof FilePermission))
1136 throw new IllegalArgumentException("invalid permission: "+
1137 permission);
1138 if (isReadOnly())
1139 throw new SecurityException(
1140 "attempt to add a Permission to a readonly PermissionCollection");
1141
1142 FilePermission fp = (FilePermission)permission;
1143
1144 // Add permission to map if it is absent, or replace with new
1145 // permission if applicable.
1146 perms.merge(fp.getName(), fp,
1147 new java.util.function.BiFunction<>() {
1148 @Override
1149 public Permission apply(Permission existingVal,
1150 Permission newVal) {
1151 int oldMask = ((FilePermission)existingVal).getMask();
1152 int newMask = ((FilePermission)newVal).getMask();
1153 if (oldMask != newMask) {
1154 int effective = oldMask | newMask;
1155 if (effective == newMask) {
1156 return newVal;
1157 }
1158 if (effective != oldMask) {
1159 return ((FilePermission)newVal)
1160 .withNewActions(effective);
1161 }
1162 }
1163 return existingVal;
1164 }
1165 }
1166 );
1167 }
1168
1169 /**
1170 * Check and see if this set of permissions implies the permissions
1171 * expressed in "permission".
1172 *
1173 * @param permission the Permission object to compare
1174 *
1175 * @return true if "permission" is a proper subset of a permission in
1176 * the set, false if not.
1177 */
1178 @Override
1179 public boolean implies(Permission permission) {
1180 if (! (permission instanceof FilePermission))
1181 return false;
1182
1183 FilePermission fperm = (FilePermission) permission;
1184
1185 int desired = fperm.getMask();
1186 int effective = 0;
1187 int needed = desired;
1188
1189 for (Permission perm : perms.values()) {
1190 FilePermission fp = (FilePermission)perm;
1191 if (((needed & fp.getMask()) != 0) && fp.impliesIgnoreMask(fperm)) {
1192 effective |= fp.getMask();
1193 if ((effective & desired) == desired) {
1194 return true;
1195 }
1196 needed = (desired ^ effective);
1197 }
1198 }
1199 return false;
1200 }
1201
1202 /**
1203 * Returns an enumeration of all the FilePermission objects in the
1204 * container.
1205 *
1206 * @return an enumeration of all the FilePermission objects.
1207 */
1208 @Override
1209 public Enumeration<Permission> elements() {
1210 return perms.elements();
1211 }
1212
1213 private static final long serialVersionUID = 2202956749081564585L;
1214
1215 // Need to maintain serialization interoperability with earlier releases,
1216 // which had the serializable field:
1217 // private Vector permissions;
1218
1219 /**
1220 * @serialField permissions java.util.Vector
1221 * A list of FilePermission objects.
1222 */
1223 private static final ObjectStreamField[] serialPersistentFields = {
1224 new ObjectStreamField("permissions", Vector.class),
1225 };
1226
1227 /**
1228 * @serialData "permissions" field (a Vector containing the FilePermissions).
1229 */
1230 /*
1231 * Writes the contents of the perms field out as a Vector for
1232 * serialization compatibility with earlier releases.
1233 */
1234 private void writeObject(ObjectOutputStream out) throws IOException {
1235 // Don't call out.defaultWriteObject()
1236
1237 // Write out Vector
1238 Vector<Permission> permissions = new Vector<>(perms.values());
1239
1240 ObjectOutputStream.PutField pfields = out.putFields();
1241 pfields.put("permissions", permissions);
1242 out.writeFields();
1243 }
1244
1245 /*
1246 * Reads in a Vector of FilePermissions and saves them in the perms field.
1247 */
1248 private void readObject(ObjectInputStream in)
1249 throws IOException, ClassNotFoundException
1250 {
1251 // Don't call defaultReadObject()
1252
1253 // Read in serialized fields
1254 ObjectInputStream.GetField gfields = in.readFields();
1255
1256 // Get the one we want
1257 @SuppressWarnings("unchecked")
1258 Vector<Permission> permissions = (Vector<Permission>)gfields.get("permissions", null);
1259 perms = new ConcurrentHashMap<>(permissions.size());
1260 for (Permission perm : permissions) {
1261 perms.put(perm.getName(), perm);
1262 }
1263 }
1264 }