/* * Copyright (c) 1997, 2005, 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.security.*; import java.util.Enumeration; import java.util.List; import java.util.ArrayList; import java.util.StringTokenizer; import java.util.Vector; import java.util.Collections; import java.io.ObjectStreamField; import java.io.ObjectOutputStream; import java.io.ObjectInputStream; import java.io.IOException; import sun.security.util.SecurityConstants; /** {@collect.stats} * {@description.open} * This class represents access to a file or directory. A FilePermission consists * of a pathname and a set of actions valid for that pathname. * <P> * Pathname is the pathname of the file or directory granted the specified * actions. A pathname that ends in "/*" (where "/" is * the file separator character, <code>File.separatorChar</code>) 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. A pathname consisting of * the special token "<<ALL FILES>>" matches <b>any</b> file. * <P> * 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. * <P> * 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", and "delete". Their meaning is defined as follows: * <P> * <DL> * <DT> read <DD> read permission * <DT> write <DD> write permission * <DT> execute * <DD> execute permission. Allows <code>Runtime.exec</code> to * be called. Corresponds to <code>SecurityManager.checkExec</code>. * <DT> delete * <DD> delete permission. Allows <code>File.delete</code> to * be called. Corresponds to <code>SecurityManager.checkDelete</code>. * </DL> * <P> * The actions string is converted to lowercase before processing. * <P> * Be careful when granting FilePermissions. Think about the implications * of granting read and especially write access to various files and * directories. The "<<ALL FILES>>" permission with write action is * especially dangerous. This grants permission to write to the entire * file system. One thing this effectively allows is replacement of the * system binary, including the JVM runtime environment. * * <p>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. * {@description.close} * * @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 { /** {@collect.stats} * {@description.open} * Execute action. * {@description.close} */ private final static int EXECUTE = 0x1; /** {@collect.stats} * {@description.open} * Write action. * {@description.close} */ private final static int WRITE = 0x2; /** {@collect.stats} * {@description.open} * Read action. * {@description.close} */ private final static int READ = 0x4; /** {@collect.stats} * {@description.open} * Delete action. * {@description.close} */ private final static int DELETE = 0x8; /** {@collect.stats} * {@description.open} * All actions (read,write,execute,delete) * {@description.close} */ private final static int ALL = READ|WRITE|EXECUTE|DELETE; /** {@collect.stats} * {@description.open} * No actions. * {@description.close} */ private final static 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; /** {@collect.stats} * {@description.open} * the actions string. * {@description.close} * * @serial */ private String actions; // Left null as long as possible, then // created and re-used in the getAction function. // canonicalized dir path. In the case of // directories, it is the name "/blah/*" or "/blah/-" without // the last character (the "*" or "-"). private transient String cpath; // static Strings used by init(int mask) private static final char RECURSIVE_CHAR = '-'; private static final char WILD_CHAR = '*'; /* public String toString() { StringBuffer sb = new StringBuffer(); sb.append("***\n"); sb.append("cpath = "+cpath+"\n"); sb.append("mask = "+mask+"\n"); sb.append("actions = "+getActions()+"\n"); sb.append("directory = "+directory+"\n"); sb.append("recursive = "+recursive+"\n"); sb.append("***\n"); return sb.toString(); } */ private static final long serialVersionUID = 7930732926638008763L; /** {@collect.stats} * {@description.open} * initialize a FilePermission object. Common to all constructors. * Also called during de-serialization. * {@description.close} * * @param mask the actions mask to use. * */ private void init(int mask) { if ((mask & ALL) != mask) throw new IllegalArgumentException("invalid actions mask"); if (mask == NONE) throw new IllegalArgumentException("invalid actions mask"); if ((cpath = getName()) == null) throw new NullPointerException("name can't be null"); this.mask = mask; if (cpath.equals("<<ALL FILES>>")) { directory = true; recursive = true; cpath = ""; return; } // store only the canonical cpath if possible cpath = AccessController.doPrivileged(new PrivilegedAction<String>() { public String run() { try { return sun.security.provider.PolicyFile.canonPath(cpath); } catch (IOException ioe) { return cpath; } } }); int len = cpath.length(); char last = ((len > 0) ? cpath.charAt(len - 1) : 0); if (last == RECURSIVE_CHAR && cpath.charAt(len - 2) == File.separatorChar) { directory = true; recursive = true; cpath = cpath.substring(0, --len); } else if (last == WILD_CHAR && cpath.charAt(len - 2) == File.separatorChar) { directory = true; //recursive = false; cpath = cpath.substring(0, --len); } else { // overkill since they are initialized to false, but // commented out here to remind us... //directory = false; //recursive = false; } // XXX: at this point the path should be absolute. die if it isn't? } /** {@collect.stats} * {@description.open} * Creates a new FilePermission object with the specified actions. * <i>path</i> is the pathname of a file or directory, and <i>actions</i> * contains a comma-separated list of the desired actions granted on the * file or directory. Possible actions are * "read", "write", "execute", and "delete". * * <p>A pathname that ends in "/*" (where "/" is * the file separator character, <code>File.separatorChar</code>) * 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 * "<<ALL FILES>>" matches any file. * * <p>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. * * <p>A pathname containing an empty string represents an empty path. * {@description.close} * * @param path the pathname of the file/directory. * @param actions the action string. * * @throws IllegalArgumentException * If actions is <code>null</code>, empty or contains an action * other than the specified possible actions. */ public FilePermission(String path, String actions) { super(path); init(getMask(actions)); } /** {@collect.stats} * {@description.open} * 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 * <code>implies</code> method. * {@description.close} * * @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); } /** {@collect.stats} * {@description.open} * Checks if this FilePermission object "implies" the specified permission. * <P> * More specifically, this method returns true if:<p> * <ul> * <li> <i>p</i> is an instanceof FilePermission,<p> * <li> <i>p</i>'s actions are a proper subset of this * object's actions, and <p> * <li> <i>p</i>'s pathname is implied by this object's * pathname. For example, "/tmp/*" implies "/tmp/foo", since * "/tmp/*" encompasses all files in the "/tmp" directory, * including the one named "foo". * </ul> * {@description.close} * * @param p the permission to check against. * * @return <code>true</code> if the specified permission is not * <code>null</code> and is implied by this object, * <code>false</code> otherwise. */ 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); } /** {@collect.stats} * {@description.open} * 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. * {@description.close} * * @param that the FilePermission to check against. * @param exact return immediately if the masks are not equal * @return the effective mask */ boolean impliesIgnoreMask(FilePermission that) { 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)); } } /** {@collect.stats} * {@description.open} * Checks two FilePermission objects for equality. Checks that <i>obj</i> is * a FilePermission, and has the same pathname and actions as this object. * <P> * {@description.close} * @param obj the object we are testing for equality with this object. * @return <code>true</code> if obj is a FilePermission, and has the same * pathname and actions as this FilePermission object, * <code>false</code> otherwise. */ public boolean equals(Object obj) { if (obj == this) return true; if (! (obj instanceof FilePermission)) return false; FilePermission that = (FilePermission) obj; return (this.mask == that.mask) && this.cpath.equals(that.cpath) && (this.directory == that.directory) && (this.recursive == that.recursive); } /** {@collect.stats} * {@description.open} * Returns the hash code value for this object. * {@description.close} * * @return a hash code value for this object. */ public int hashCode() { return this.cpath.hashCode(); } /** {@collect.stats} * {@description.open} * Converts an actions String to an actions mask. * {@description.close} * * @param action the action string. * @return the actions mask. */ private static int getMask(String actions) { int mask = NONE; // Null action valid? if (actions == null) { return mask; } // Check against use of constants (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; } 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 { // 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; /*FALLTHROUGH*/ 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; } /** {@collect.stats} * {@description.open} * Return the current action mask. Used by the FilePermissionCollection. * {@description.close} * * @return the actions mask. */ int getMask() { return mask; } /** {@collect.stats} * {@description.open} * Return the canonical string representation of the actions. * Always returns present actions in the following order: * read, write, execute, delete. * {@description.close} * * @return the canonical string representation of the actions. */ private static String getActions(int mask) { StringBuilder sb = new StringBuilder(); boolean comma = false; if ((mask & READ) == READ) { comma = true; sb.append("read"); } if ((mask & WRITE) == WRITE) { if (comma) sb.append(','); else comma = true; sb.append("write"); } if ((mask & EXECUTE) == EXECUTE) { if (comma) sb.append(','); else comma = true; sb.append("execute"); } if ((mask & DELETE) == DELETE) { if (comma) sb.append(','); else comma = true; sb.append("delete"); } return sb.toString(); } /** {@collect.stats} * {@description.open} * Returns the "canonical string representation" of the actions. * That is, this method always returns present actions in the following order: * read, write, execute, delete. For example, if this FilePermission object * allows both write and read actions, a call to <code>getActions</code> * will return the string "read,write". * {@description.close} * * @return the canonical string representation of the actions. */ public String getActions() { if (actions == null) actions = getActions(this.mask); return actions; } /** {@collect.stats} * {@description.open} * Returns a new PermissionCollection object for storing FilePermission * objects. * <p> * 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 <code>implies</code> * method to be implemented in an efficient (and consistent) manner. * * <p>For example, if you have two FilePermissions: * <OL> * <LI> <code>"/tmp/-", "read"</code> * <LI> <code>"/tmp/scratch/foo", "write"</code> * </OL> * * <p>and you are calling the <code>implies</code> method with the FilePermission: * * <pre> * "/tmp/scratch/foo", "read,write", * </pre> * * then the <code>implies</code> function must * take into account both the "/tmp/-" and "/tmp/scratch/foo" * permissions, so the effective permission is "read,write", * and <code>implies</code> returns true. The "implies" semantics for * FilePermissions are handled properly by the PermissionCollection object * returned by this <code>newPermissionCollection</code> method. * {@description.close} * * @return a new PermissionCollection object suitable for storing * FilePermissions. */ public PermissionCollection newPermissionCollection() { return new FilePermissionCollection(); } /** {@collect.stats} * {@description.open} * 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. * {@description.close} */ 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(); } /** {@collect.stats} * {@description.open} * readObject is called to restore the state of the FilePermission from * a stream. * {@description.close} */ private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException { // Read in the actions, then restore everything else by calling init. s.defaultReadObject(); init(getMask(actions)); } } /** {@collect.stats} * {@description.open} * 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: * <OL> * <LI> "/tmp/-", "read" * <LI> "/tmp/scratch/foo", "write" * </OL> * 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". * {@description.close} * * @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 List perms; /** {@collect.stats} * {@description.open} * Create an empty FilePermissions object. * {@description.close} * */ public FilePermissionCollection() { perms = new ArrayList(); } /** {@collect.stats} * {@description.open} * Adds a permission to the FilePermissions. The key for the hash is * permission.path. * {@description.close} * * @param permission the Permission object to add. * * @exception IllegalArgumentException - if the permission is not a * FilePermission * * @exception SecurityException - if this FilePermissionCollection object * has been marked readonly */ public void add(Permission permission) { if (! (permission instanceof FilePermission)) throw new IllegalArgumentException("invalid permission: "+ permission); if (isReadOnly()) throw new SecurityException( "attempt to add a Permission to a readonly PermissionCollection"); synchronized (this) { perms.add(permission); } } /** {@collect.stats} * {@description.open} * Check and see if this set of permissions implies the permissions * expressed in "permission". * {@description.close} * * @param p the Permission object to compare * * @return true if "permission" is a proper subset of a permission in * the set, false if not. */ public boolean implies(Permission permission) { if (! (permission instanceof FilePermission)) return false; FilePermission fp = (FilePermission) permission; int desired = fp.getMask(); int effective = 0; int needed = desired; synchronized (this) { int len = perms.size(); for (int i = 0; i < len; i++) { FilePermission x = (FilePermission) perms.get(i); if (((needed & x.getMask()) != 0) && x.impliesIgnoreMask(fp)) { effective |= x.getMask(); if ((effective & desired) == desired) return true; needed = (desired ^ effective); } } } return false; } /** {@collect.stats} * {@description.open} * Returns an enumeration of all the FilePermission objects in the * container. * {@description.close} * * @return an enumeration of all the FilePermission objects. */ public Enumeration elements() { // Convert Iterator into Enumeration synchronized (this) { return Collections.enumeration(perms); } } private static final long serialVersionUID = 2202956749081564585L; // Need to maintain serialization interoperability with earlier releases, // which had the serializable field: // private Vector permissions; /** {@collect.stats} * @serialField permissions java.util.Vector * A list of FilePermission objects. */ private static final ObjectStreamField[] serialPersistentFields = { new ObjectStreamField("permissions", Vector.class), }; /** {@collect.stats} * @serialData "permissions" field (a Vector containing the FilePermissions). */ /* * Writes the contents of the perms field out as a Vector for * serialization compatibility with earlier releases. */ private void writeObject(ObjectOutputStream out) throws IOException { // Don't call out.defaultWriteObject() // Write out Vector Vector permissions = new Vector(perms.size()); synchronized (this) { permissions.addAll(perms); } ObjectOutputStream.PutField pfields = out.putFields(); pfields.put("permissions", permissions); out.writeFields(); } /* * Reads in a Vector of FilePermissions and saves them in the perms field. */ private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { // Don't call defaultReadObject() // Read in serialized fields ObjectInputStream.GetField gfields = in.readFields(); // Get the one we want Vector permissions = (Vector)gfields.get("permissions", null); perms = new ArrayList(permissions.size()); perms.addAll(permissions); } }