/* * @(#)PropertyPermission.java 1.33 03/12/19 * * Copyright 2004 Sun Microsystems, Inc. All rights reserved. * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. */ package java.util; import java.io.Serializable; import java.io.IOException; import java.security.*; import java.util.Map; import java.util.HashMap; import java.util.Enumeration; import java.util.Hashtable; 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; /** * This class is for property permissions. * *
* The name is the name of the property ("java.home", * "os.name", etc). The naming * convention follows the hierarchical property naming convention. * Also, an asterisk * may appear at the end of the name, following a ".", or by itself, to * signify a wildcard match. For example: "java.*" or "*" is valid, * "*java" or "a*b" is not valid. *
*
* The actions to be granted are passed to the constructor in a string containing * a list of zero or more comma-separated keywords. The possible keywords are * "read" and "write". Their meaning is defined as follows: *
*
System.getProperty
to
* be called.
* System.setProperty
to
* be called.
* * The actions string is converted to lowercase before processing. *
* Care should be taken before granting code permission to access * certain system properties. For example, granting permission to * access the "java.home" system property gives potentially malevolent * code sensitive information about the system environment (the Java * installation directory). Also, granting permission to access * the "user.name" and "user.home" system properties gives potentially * malevolent code sensitive information about the user environment * (the user's account name and home directory). * * @see java.security.BasicPermission * @see java.security.Permission * @see java.security.Permissions * @see java.security.PermissionCollection * @see java.lang.SecurityManager * * @version 1.33 03/12/19 * * @author Roland Schemers * @since 1.2 * * @serial exclude */ public final class PropertyPermission extends BasicPermission { /** * Read action. */ private final static int READ = 0x1; /** * Write action. */ private final static int WRITE = 0x2; /** * All actions (read,write); */ private final static int ALL = READ|WRITE; /** * No actions. */ private final static int NONE = 0x0; /** * The actions mask. * */ private transient int mask; /** * The actions string. * * @serial */ private String actions; // Left null as long as possible, then // created and re-used in the getAction function. /** * initialize a PropertyPermission object. Common to all constructors. * Also called during de-serialization. * * @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 (getName() == null) throw new NullPointerException("name can't be null"); this.mask = mask; } /** * Creates a new PropertyPermission object with the specified name. * The name is the name of the system property, and * actions contains a comma-separated list of the * desired actions granted on the property. Possible actions are * "read" and "write". * * @param name the name of the PropertyPermission. * @param actions the actions string. */ public PropertyPermission(String name, String actions) { super(name,actions); init(getMask(actions)); } /** * Checks if this PropertyPermission object "implies" the specified * permission. *
* More specifically, this method returns true if:
*
*
*
* @param obj the object we are testing for equality with this object.
* @return true if obj is a PropertyPermission, and has the same name and
* actions as this PropertyPermission object.
*/
public boolean equals(Object obj) {
if (obj == this)
return true;
if (! (obj instanceof PropertyPermission))
return false;
PropertyPermission that = (PropertyPermission) obj;
return (this.mask == that.mask) &&
(this.getName().equals(that.getName()));
}
/**
* Returns the hash code value for this object.
* The hash code used is the hash code of this permissions name, that is,
* getName().hashCode()
, where getName
is
* from the Permission superclass.
*
* @return a hash code value for this object.
*/
public int hashCode() {
return this.getName().hashCode();
}
/**
* Converts an actions String to an actions mask.
*
* @param action the action string.
* @return the actions mask.
*/
private static int getMask(String actions) {
int mask = NONE;
if (actions == null) {
return mask;
}
// Check against use of constants (used heavily within the JDK)
if (actions == SecurityConstants.PROPERTY_READ_ACTION) {
return READ;
} if (actions == SecurityConstants.PROPERTY_WRITE_ACTION) {
return WRITE;
} else if (actions == SecurityConstants.PROPERTY_RW_ACTION) {
return READ|WRITE;
}
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 {
// 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;
}
/**
* Return the canonical string representation of the actions.
* Always returns present actions in the following order:
* read, write.
*
* @return the canonical string representation of the actions.
*/
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");
}
return sb.toString();
}
/**
* Returns the "canonical string representation" of the actions.
* That is, this method always returns present actions in the following order:
* read, write. For example, if this PropertyPermission 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.
*/
public String getActions()
{
if (actions == null)
actions = getActions(this.mask);
return actions;
}
/**
* Return the current action mask.
* Used by the PropertyPermissionCollection
*
* @return the actions mask.
*/
int getMask() {
return mask;
}
/**
* Returns a new PermissionCollection object for storing
* PropertyPermission objects.
*
* * @return a new PermissionCollection object suitable for storing * PropertyPermissions. */ public PermissionCollection newPermissionCollection() { return new PropertyPermissionCollection(); } private static final long serialVersionUID = 885438825399942851L; /** * WriteObject is called to save the state of the PropertyPermission * to a stream. The actions are serialized, and the superclass * takes care of the name. */ private synchronized void writeObject(java.io.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 PropertyPermission from * a stream. */ private synchronized void readObject(java.io.ObjectInputStream s) throws IOException, ClassNotFoundException { // Read in the action, then initialize the rest s.defaultReadObject(); init(getMask(actions)); } } /** * A PropertyPermissionCollection stores a set of PropertyPermission * permissions. * * @see java.security.Permission * @see java.security.Permissions * @see java.security.PermissionCollection * * @version 1.33, 12/19/03 * * @author Roland Schemers * * @serial include */ final class PropertyPermissionCollection extends PermissionCollection implements Serializable { /** * Key is property name; value is PropertyPermission. * Not serialized; see serialization section at end of class. */ private transient Map perms; /** * Boolean saying if "*" is in the collection. * * @see #serialPersistentFields */ // No sync access; OK for this to be stale. private boolean all_allowed; /** * Create an empty PropertyPermissions object. * */ public PropertyPermissionCollection() { perms = new HashMap(32); // Capacity for default policy all_allowed = false; } /** * Adds a permission to the PropertyPermissions. The key for the hash is * the name. * * @param permission the Permission object to add. * * @exception IllegalArgumentException - if the permission is not a * PropertyPermission * * @exception SecurityException - if this PropertyPermissionCollection * object has been marked readonly */ public void add(Permission permission) { if (! (permission instanceof PropertyPermission)) throw new IllegalArgumentException("invalid permission: "+ permission); if (isReadOnly()) throw new SecurityException( "attempt to add a Permission to a readonly PermissionCollection"); PropertyPermission pp = (PropertyPermission) permission; String propName = pp.getName(); synchronized (this) { PropertyPermission existing = (PropertyPermission) perms.get(propName); if (existing != null) { int oldMask = existing.getMask(); int newMask = pp.getMask(); if (oldMask != newMask) { int effective = oldMask | newMask; String actions = PropertyPermission.getActions(effective); perms.put(propName, new PropertyPermission(propName, actions)); } } else { perms.put(propName, permission); } } if (!all_allowed) { if (propName.equals("*")) all_allowed = true; } } /** * Check and see if this set of permissions implies the permissions * expressed in "permission". * * @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 PropertyPermission)) return false; PropertyPermission pp = (PropertyPermission) permission; PropertyPermission x; int desired = pp.getMask(); int effective = 0; // short circuit if the "*" Permission was added if (all_allowed) { synchronized (this) { x = (PropertyPermission) perms.get("*"); } if (x != null) { effective |= x.getMask(); if ((effective & desired) == desired) return true; } } // strategy: // Check for full match first. Then work our way up the // name looking for matches on a.b.* String name = pp.getName(); //System.out.println("check "+name); synchronized (this) { x = (PropertyPermission) perms.get(name); } if (x != null) { // we have a direct hit! effective |= x.getMask(); if ((effective & desired) == desired) return true; } // work our way up the tree... int last, offset; offset = name.length()-1; while ((last = name.lastIndexOf(".", offset)) != -1) { name = name.substring(0, last+1) + "*"; //System.out.println("check "+name); synchronized (this) { x = (PropertyPermission) perms.get(name); } if (x != null) { effective |= x.getMask(); if ((effective & desired) == desired) return true; } offset = last -1; } // we don't have to check for "*" as it was already checked // at the top (all_allowed), so we just return false return false; } /** * Returns an enumeration of all the PropertyPermission objects in the * container. * * @return an enumeration of all the PropertyPermission objects. */ public Enumeration elements() { // Convert Iterator of Map values into an Enumeration synchronized (this) { return Collections.enumeration(perms.values()); } } private static final long serialVersionUID = 7015263904581634791L; // Need to maintain serialization interoperability with earlier releases, // which had the serializable field: // // Table of permissions. // // @serial // // private Hashtable permissions; /** * @serialField permissions java.util.Hashtable * A table of the PropertyPermissions. * @serialField all_allowed boolean * boolean saying if "*" is in the collection. */ private static final ObjectStreamField[] serialPersistentFields = { new ObjectStreamField("permissions", Hashtable.class), new ObjectStreamField("all_allowed", Boolean.TYPE), }; /** * @serialData Default fields. */ /* * Writes the contents of the perms field out as a Hashtable for * serialization compatibility with earlier releases. all_allowed * unchanged. */ private void writeObject(ObjectOutputStream out) throws IOException { // Don't call out.defaultWriteObject() // Copy perms into a Hashtable Hashtable permissions = new Hashtable(perms.size()*2); synchronized (this) { permissions.putAll(perms); } // Write out serializable fields ObjectOutputStream.PutField pfields = out.putFields(); pfields.put("all_allowed", all_allowed); pfields.put("permissions", permissions); out.writeFields(); } /* * Reads in a Hashtable of PropertyPermissions and saves them in the * perms field. Reads in all_allowed. */ private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { // Don't call defaultReadObject() // Read in serialized fields ObjectInputStream.GetField gfields = in.readFields(); // Get all_allowed all_allowed = gfields.get("all_allowed", false); // Get permissions Hashtable permissions = (Hashtable)gfields.get("permissions", null); perms = new HashMap(permissions.size()*2); perms.putAll(permissions); } }