/* * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.io; import java.nio.file.*; import java.security.*; import java.util.Enumeration; import java.util.Objects; import java.util.StringJoiner; import java.util.Vector; import java.util.concurrent.ConcurrentHashMap; import jdk.internal.access.JavaIOFilePermissionAccess; import jdk.internal.access.SharedSecrets; import sun.nio.fs.DefaultFileSystemProvider; import sun.security.action.GetPropertyAction; import sun.security.util.FilePermCompat; import sun.security.util.SecurityConstants; /** * This class represents access to a file or directory. A FilePermission consists * of a pathname and a set of actions valid for that pathname. *
* Pathname is the pathname of the file or directory granted the specified
* actions. A pathname that ends in "/*" (where "/" is
* the file separator character, File.separatorChar
) indicates
* all the files and directories contained in that directory. A pathname
* that ends with "/-" indicates (recursively) all files
* and subdirectories contained in that directory. Such a pathname is called
* a wildcard pathname. Otherwise, it's a simple pathname.
*
* A pathname consisting of the special token {@literal "<
* Note: A pathname consisting of a single "*" indicates all the files
* in the current directory, while a pathname consisting of a single "-"
* indicates all the files in the current directory and
* (recursively) all files and subdirectories contained in the current
* directory.
*
* The actions to be granted are passed to the constructor in a string containing
* a list of one or more comma-separated keywords. The possible keywords are
* "read", "write", "execute", "delete", and "readlink". Their meaning is
* defined as follows:
*
*
* The actions string is converted to lowercase before processing.
*
* Be careful when granting FilePermissions. Think about the implications
* of granting read and especially write access to various files and
* directories. The {@literal "<
* Please note: Code can always read a file from the same
* directory it's in (or a subdirectory of that directory); it does not
* need explicit permission to do so.
*
* @see java.security.Permission
* @see java.security.Permissions
* @see java.security.PermissionCollection
*
*
* @author Marianne Mueller
* @author Roland Schemers
* @since 1.2
*
* @serial exclude
*/
public final class FilePermission extends Permission implements Serializable {
/**
* Execute action.
*/
private static final int EXECUTE = 0x1;
/**
* Write action.
*/
private static final int WRITE = 0x2;
/**
* Read action.
*/
private static final int READ = 0x4;
/**
* Delete action.
*/
private static final int DELETE = 0x8;
/**
* Read link action.
*/
private static final int READLINK = 0x10;
/**
* All actions (read,write,execute,delete,readlink)
*/
private static final int ALL = READ|WRITE|EXECUTE|DELETE|READLINK;
/**
* No actions.
*/
private static final int NONE = 0x0;
// the actions mask
private transient int mask;
// does path indicate a directory? (wildcard or recursive)
private transient boolean directory;
// is it a recursive directory specification?
private transient boolean recursive;
/**
* the actions string.
*
* @serial
*/
private String actions; // Left null as long as possible, then
// created and re-used in the getAction function.
// canonicalized dir path. used by the "old" behavior (nb == false).
// In the case of directories, it is the name "/blah/*" or "/blah/-"
// without the last character (the "*" or "-").
private transient String cpath;
// Following fields used by the "new" behavior (nb == true), in which
// input path is not canonicalized. For compatibility (so that granting
// FilePermission on "x" allows reading "`pwd`/x", an alternative path
// can be added so that both can be used in an implies() check. Please note
// the alternative path only deals with absolute/relative path, and does
// not deal with symlink/target.
private transient Path npath; // normalized dir path.
private transient Path npath2; // alternative normalized dir path.
private transient boolean allFiles; // whether this is < A pathname that ends in "/*" (where "/" is
* the file separator character, A pathname consisting of a single "*" indicates all the files
* in the current directory, while a pathname consisting of a single "-"
* indicates all the files in the current directory and
* (recursively) all files and subdirectories contained in the current
* directory.
*
* A pathname containing an empty string represents an empty path.
*
* @implNote In this implementation, the
* {@systemProperty jdk.io.permissionsUseCanonicalPath} system property
* dictates how the {@code path} argument is processed and stored.
*
* If the value of the system property is set to {@code true}, {@code path}
* is canonicalized and stored as a String object named {@code cpath}.
* This means a relative path is converted to an absolute path, a Windows
* DOS-style 8.3 path is expanded to a long path, and a symbolic link is
* resolved to its target, etc.
*
* If the value of the system property is set to {@code false}, {@code path}
* is converted to a {@link java.nio.file.Path} object named {@code npath}
* after {@link Path#normalize() normalization}. No canonicalization is
* performed which means the underlying file system is not accessed.
* If an {@link InvalidPathException} is thrown during the conversion,
* this {@code FilePermission} will be labeled as invalid.
*
* In either case, the "*" or "-" character at the end of a wildcard
* {@code path} is removed before canonicalization or normalization.
* It is stored in a separate wildcard flag field.
*
* The default value of the {@code jdk.io.permissionsUseCanonicalPath}
* system property is {@code false} in this implementation.
*
* @param path the pathname of the file/directory.
* @param actions the action string.
*
* @throws IllegalArgumentException
* If actions is
* More specifically, this method returns true if:
*
* Precisely, a simple pathname implies another simple pathname
* if and only if they are equal. A simple pathname never implies
* a wildcard pathname. A wildcard pathname implies another wildcard
* pathname if and only if all simple pathnames implied by the latter
* are implied by the former. A wildcard pathname implies a simple
* pathname if and only if
*
* {@literal "<
* If {@code jdk.io.permissionsUseCanonicalPath} is {@code false}, a
* simple {@code npath} is inside a wildcard {@code npath} if and only if
* {@code simple_npath.relativize(wildcard_npath)} is exactly "..",
* a simple {@code npath} is recursively inside a wildcard {@code npath}
* if and only if {@code simple_npath.relativize(wildcard_npath)} is a
* series of one or more "..". This means "/-" implies "/foo" but not "foo".
*
* An invalid {@code FilePermission} does not imply any object except for
* itself. An invalid {@code FilePermission} is not implied by any object
* except for itself or a {@code FilePermission} on
* {@literal "<
* When {@code jdk.io.permissionsUseCanonicalPath} is {@code false}, an
* invalid {@code FilePermission} does not equal to any object except
* for itself, even if they are created using the same invalid path.
*
* @param obj the object we are testing for equality with this object.
* @return
* FilePermission objects must be stored in a manner that allows them
* to be inserted into the collection in any order, but that also enables the
* PermissionCollection For example, if you have two FilePermissions:
* and you are calling the
*
* Runtime.exec
to
* be called. Corresponds to SecurityManager.checkExec
.
* File.delete
to
* be called. Corresponds to SecurityManager.checkDelete
.
* File.separatorChar
)
* indicates all the files and directories contained in that directory.
* A pathname that ends with "/-" indicates (recursively) all files and
* subdirectories contained in that directory. The special pathname
* {@literal "<null
, empty or contains an action
* other than the specified possible actions.
*/
public FilePermission(String path, String actions) {
super(path);
init(getMask(actions));
}
/**
* Creates a new FilePermission object using an action mask.
* More efficient than the FilePermission(String, String) constructor.
* Can be used from within
* code that needs to create a FilePermission object to pass into the
* implies
method.
*
* @param path the pathname of the file/directory.
* @param mask the action mask to use.
*/
// package private for use by the FilePermissionCollection add method
FilePermission(String path, int mask) {
super(path);
init(mask);
}
/**
* Checks if this FilePermission object "implies" the specified permission.
*
*
*
*
* true
if the specified permission is not
* null
and is implied by this object,
* false
otherwise.
*/
@Override
public boolean implies(Permission p) {
if (!(p instanceof FilePermission))
return false;
FilePermission that = (FilePermission) p;
// we get the effective mask. i.e., the "and" of this and that.
// They must be equal to that.mask for implies to return true.
return ((this.mask & that.mask) == that.mask) && impliesIgnoreMask(that);
}
/**
* Checks if the Permission's actions are a proper subset of the
* this object's actions. Returns the effective mask iff the
* this FilePermission's path also implies that FilePermission's path.
*
* @param that the FilePermission to check against.
* @return the effective mask
*/
boolean impliesIgnoreMask(FilePermission that) {
if (FilePermCompat.nb) {
if (this == that) {
return true;
}
if (allFiles) {
return true;
}
if (this.invalid || that.invalid) {
return false;
}
if (that.allFiles) {
return false;
}
// Left at least same level of wildness as right
if ((this.recursive && that.recursive) != that.recursive
|| (this.directory && that.directory) != that.directory) {
return false;
}
// Same npath is good as long as both or neither are directories
if (this.npath.equals(that.npath)
&& this.directory == that.directory) {
return true;
}
int diff = containsPath(this.npath, that.npath);
// Right inside left is good if recursive
if (diff >= 1 && recursive) {
return true;
}
// Right right inside left if it is element in set
if (diff == 1 && directory && !that.directory) {
return true;
}
// Hack: if a npath2 field exists, apply the same checks
// on it as a fallback.
if (this.npath2 != null) {
if (this.npath2.equals(that.npath)
&& this.directory == that.directory) {
return true;
}
diff = containsPath(this.npath2, that.npath);
if (diff >= 1 && recursive) {
return true;
}
if (diff == 1 && directory && !that.directory) {
return true;
}
}
return false;
} else {
if (this.directory) {
if (this.recursive) {
// make sure that.path is longer then path so
// something like /foo/- does not imply /foo
if (that.directory) {
return (that.cpath.length() >= this.cpath.length()) &&
that.cpath.startsWith(this.cpath);
} else {
return ((that.cpath.length() > this.cpath.length()) &&
that.cpath.startsWith(this.cpath));
}
} else {
if (that.directory) {
// if the permission passed in is a directory
// specification, make sure that a non-recursive
// permission (i.e., this object) can't imply a recursive
// permission.
if (that.recursive)
return false;
else
return (this.cpath.equals(that.cpath));
} else {
int last = that.cpath.lastIndexOf(File.separatorChar);
if (last == -1)
return false;
else {
// this.cpath.equals(that.cpath.substring(0, last+1));
// Use regionMatches to avoid creating new string
return (this.cpath.length() == (last + 1)) &&
this.cpath.regionMatches(0, that.cpath, 0, last + 1);
}
}
}
} else if (that.directory) {
// if this is NOT recursive/wildcarded,
// do not let it imply a recursive/wildcarded permission
return false;
} else {
return (this.cpath.equals(that.cpath));
}
}
}
/**
* Returns the depth between an outer path p1 and an inner path p2. -1
* is returned if
*
* - p1 does not contains p2.
* - this is not decidable. For example, p1="../x", p2="y".
* - the depth is not decidable. For example, p1="/", p2="x".
*
* This method can return 2 if the depth is greater than 2.
*
* @param p1 the expected outer path, normalized
* @param p2 the expected inner path, normalized
* @return the depth in between
*/
private static int containsPath(Path p1, Path p2) {
// Two paths must have the same root. For example,
// there is no contains relation between any two of
// "/x", "x", "C:/x", "C:x", and "//host/share/x".
if (!Objects.equals(p1.getRoot(), p2.getRoot())) {
return -1;
}
// Empty path (i.e. "." or "") is a strange beast,
// because its getNameCount()==1 but getName(0) is null.
// It's better to deal with it separately.
if (p1.equals(EMPTY_PATH)) {
if (p2.equals(EMPTY_PATH)) {
return 0;
} else if (p2.getName(0).equals(DOTDOT_PATH)) {
// "." contains p2 iff p2 has no "..". Since
// a normalized path can only have 0 or more
// ".." at the beginning. We only need to look
// at the head.
return -1;
} else {
// and the distance is p2's name count. i.e.
// 3 between "." and "a/b/c".
return p2.getNameCount();
}
} else if (p2.equals(EMPTY_PATH)) {
int c1 = p1.getNameCount();
if (!p1.getName(c1 - 1).equals(DOTDOT_PATH)) {
// "." is inside p1 iff p1 is 1 or more "..".
// For the same reason above, we only need to
// look at the tail.
return -1;
}
// and the distance is the count of ".."
return c1;
}
// Good. No more empty paths.
// Common heads are removed
int c1 = p1.getNameCount();
int c2 = p2.getNameCount();
int n = Math.min(c1, c2);
int i = 0;
while (i < n) {
if (!p1.getName(i).equals(p2.getName(i)))
break;
i++;
}
// for p1 containing p2, p1 must be 0-or-more "..",
// and p2 cannot have "..". For the same reason, we only
// check tail of p1 and head of p2.
if (i < c1 && !p1.getName(c1 - 1).equals(DOTDOT_PATH)) {
return -1;
}
if (i < c2 && p2.getName(i).equals(DOTDOT_PATH)) {
return -1;
}
// and the distance is the name counts added (after removing
// the common heads).
// For example: p1 = "../../..", p2 = "../a".
// After removing the common heads, they become "../.." and "a",
// and the distance is (3-1)+(2-1) = 3.
return c1 - i + c2 - i;
}
/**
* Checks two FilePermission objects for equality. Checks that obj is
* a FilePermission, and has the same pathname and actions as this object.
*
* @implNote More specifically, two pathnames are the same if and only if
* they have the same wildcard flag and their {@code cpath}
* (if {@code jdk.io.permissionsUseCanonicalPath} is {@code true}) or
* {@code npath} (if {@code jdk.io.permissionsUseCanonicalPath}
* is {@code false}) are equal. Or they are both {@literal "<true
if obj is a FilePermission, and has the same
* pathname and actions as this FilePermission object,
* false
otherwise.
*/
@Override
public boolean equals(Object obj) {
if (obj == this)
return true;
if (! (obj instanceof FilePermission))
return false;
FilePermission that = (FilePermission) obj;
if (FilePermCompat.nb) {
if (this.invalid || that.invalid) {
return false;
}
return (this.mask == that.mask) &&
(this.allFiles == that.allFiles) &&
this.npath.equals(that.npath) &&
Objects.equals(npath2, that.npath2) &&
(this.directory == that.directory) &&
(this.recursive == that.recursive);
} else {
return (this.mask == that.mask) &&
this.cpath.equals(that.cpath) &&
(this.directory == that.directory) &&
(this.recursive == that.recursive);
}
}
/**
* Returns the hash code value for this object.
*
* @return a hash code value for this object.
*/
@Override
public int hashCode() {
if (FilePermCompat.nb) {
return Objects.hash(
mask, allFiles, directory, recursive, npath, npath2, invalid);
} else {
return 0;
}
}
/**
* Converts an actions String to an actions mask.
*
* @param actions the action string.
* @return the actions mask.
*/
private static int getMask(String actions) {
int mask = NONE;
// Null action valid?
if (actions == null) {
return mask;
}
// Use object identity comparison against known-interned strings for
// performance benefit (these values are used heavily within the JDK).
if (actions == SecurityConstants.FILE_READ_ACTION) {
return READ;
} else if (actions == SecurityConstants.FILE_WRITE_ACTION) {
return WRITE;
} else if (actions == SecurityConstants.FILE_EXECUTE_ACTION) {
return EXECUTE;
} else if (actions == SecurityConstants.FILE_DELETE_ACTION) {
return DELETE;
} else if (actions == SecurityConstants.FILE_READLINK_ACTION) {
return READLINK;
}
char[] a = actions.toCharArray();
int i = a.length - 1;
if (i < 0)
return mask;
while (i != -1) {
char c;
// skip whitespace
while ((i!=-1) && ((c = a[i]) == ' ' ||
c == '\r' ||
c == '\n' ||
c == '\f' ||
c == '\t'))
i--;
// check for the known strings
int matchlen;
if (i >= 3 && (a[i-3] == 'r' || a[i-3] == 'R') &&
(a[i-2] == 'e' || a[i-2] == 'E') &&
(a[i-1] == 'a' || a[i-1] == 'A') &&
(a[i] == 'd' || a[i] == 'D'))
{
matchlen = 4;
mask |= READ;
} else if (i >= 4 && (a[i-4] == 'w' || a[i-4] == 'W') &&
(a[i-3] == 'r' || a[i-3] == 'R') &&
(a[i-2] == 'i' || a[i-2] == 'I') &&
(a[i-1] == 't' || a[i-1] == 'T') &&
(a[i] == 'e' || a[i] == 'E'))
{
matchlen = 5;
mask |= WRITE;
} else if (i >= 6 && (a[i-6] == 'e' || a[i-6] == 'E') &&
(a[i-5] == 'x' || a[i-5] == 'X') &&
(a[i-4] == 'e' || a[i-4] == 'E') &&
(a[i-3] == 'c' || a[i-3] == 'C') &&
(a[i-2] == 'u' || a[i-2] == 'U') &&
(a[i-1] == 't' || a[i-1] == 'T') &&
(a[i] == 'e' || a[i] == 'E'))
{
matchlen = 7;
mask |= EXECUTE;
} else if (i >= 5 && (a[i-5] == 'd' || a[i-5] == 'D') &&
(a[i-4] == 'e' || a[i-4] == 'E') &&
(a[i-3] == 'l' || a[i-3] == 'L') &&
(a[i-2] == 'e' || a[i-2] == 'E') &&
(a[i-1] == 't' || a[i-1] == 'T') &&
(a[i] == 'e' || a[i] == 'E'))
{
matchlen = 6;
mask |= DELETE;
} else if (i >= 7 && (a[i-7] == 'r' || a[i-7] == 'R') &&
(a[i-6] == 'e' || a[i-6] == 'E') &&
(a[i-5] == 'a' || a[i-5] == 'A') &&
(a[i-4] == 'd' || a[i-4] == 'D') &&
(a[i-3] == 'l' || a[i-3] == 'L') &&
(a[i-2] == 'i' || a[i-2] == 'I') &&
(a[i-1] == 'n' || a[i-1] == 'N') &&
(a[i] == 'k' || a[i] == 'K'))
{
matchlen = 8;
mask |= READLINK;
} else {
// parse error
throw new IllegalArgumentException(
"invalid permission: " + actions);
}
// make sure we didn't just match the tail of a word
// like "ackbarfaccept". Also, skip to the comma.
boolean seencomma = false;
while (i >= matchlen && !seencomma) {
switch(a[i-matchlen]) {
case ',':
seencomma = true;
break;
case ' ': case '\r': case '\n':
case '\f': case '\t':
break;
default:
throw new IllegalArgumentException(
"invalid permission: " + actions);
}
i--;
}
// point i at the location of the comma minus one (or -1).
i -= matchlen;
}
return mask;
}
/**
* Return the current action mask. Used by the FilePermissionCollection.
*
* @return the actions mask.
*/
int getMask() {
return mask;
}
/**
* Return the canonical string representation of the actions.
* Always returns present actions in the following order:
* read, write, execute, delete, readlink.
*
* @return the canonical string representation of the actions.
*/
private static String getActions(int mask) {
StringJoiner sj = new StringJoiner(",");
if ((mask & READ) == READ) {
sj.add("read");
}
if ((mask & WRITE) == WRITE) {
sj.add("write");
}
if ((mask & EXECUTE) == EXECUTE) {
sj.add("execute");
}
if ((mask & DELETE) == DELETE) {
sj.add("delete");
}
if ((mask & READLINK) == READLINK) {
sj.add("readlink");
}
return sj.toString();
}
/**
* Returns the "canonical string representation" of the actions.
* That is, this method always returns present actions in the following order:
* read, write, execute, delete, readlink. For example, if this FilePermission
* object allows both write and read actions, a call to getActions
* will return the string "read,write".
*
* @return the canonical string representation of the actions.
*/
@Override
public String getActions() {
if (actions == null)
actions = getActions(this.mask);
return actions;
}
/**
* Returns a new PermissionCollection object for storing FilePermission
* objects.
* implies
* method to be implemented in an efficient (and consistent) manner.
*
*
*
*
* "/tmp/-", "read"
* "/tmp/scratch/foo", "write"
* implies
method with the FilePermission:
*
*
* "/tmp/scratch/foo", "read,write",
*
*
* then the implies
function must
* take into account both the "/tmp/-" and "/tmp/scratch/foo"
* permissions, so the effective permission is "read,write",
* and implies
returns true. The "implies" semantics for
* FilePermissions are handled properly by the PermissionCollection object
* returned by this newPermissionCollection
method.
*
* @return a new PermissionCollection object suitable for storing
* FilePermissions.
*/
@Override
public PermissionCollection newPermissionCollection() {
return new FilePermissionCollection();
}
/**
* WriteObject is called to save the state of the FilePermission
* to a stream. The actions are serialized, and the superclass
* takes care of the name.
*/
@java.io.Serial
private void writeObject(ObjectOutputStream s)
throws IOException
{
// Write out the actions. The superclass takes care of the name
// call getActions to make sure actions field is initialized
if (actions == null)
getActions();
s.defaultWriteObject();
}
/**
* readObject is called to restore the state of the FilePermission from
* a stream.
*/
@java.io.Serial
private void readObject(ObjectInputStream s)
throws IOException, ClassNotFoundException
{
// Read in the actions, then restore everything else by calling init.
s.defaultReadObject();
init(getMask(actions));
}
/**
* Create a cloned FilePermission with a different actions.
* @param effective the new actions
* @return a new object
*/
FilePermission withNewActions(int effective) {
return new FilePermission(this.getName(),
this,
this.npath,
this.npath2,
effective,
null);
}
}
/**
* A FilePermissionCollection stores a set of FilePermission permissions.
* FilePermission objects
* must be stored in a manner that allows them to be inserted in any
* order, but enable the implies function to evaluate the implies
* method.
* For example, if you have two FilePermissions:
*
*
* And you are calling the implies function with the FilePermission:
* "/tmp/scratch/foo", "read,write", then the implies function must
* take into account both the /tmp/- and /tmp/scratch/foo
* permissions, so the effective permission is "read,write".
*
* @see java.security.Permission
* @see java.security.Permissions
* @see java.security.PermissionCollection
*
*
* @author Marianne Mueller
* @author Roland Schemers
*
* @serial include
*
*/
final class FilePermissionCollection extends PermissionCollection
implements Serializable
{
// Not serialized; see serialization section at end of class
private transient ConcurrentHashMap