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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package java.security;

import sun.security.util.IOUtils;

import java.io.IOException;
import java.io.ByteArrayInputStream;
import java.security.cert.Certificate;
import java.util.ArrayList;
import java.util.Hashtable;
import java.lang.reflect.*;
import java.security.cert.*;
import java.util.List;

The UnresolvedPermission class is used to hold Permissions that
were "unresolved" when the Policy was initialized.
An unresolved permission is one whose actual Permission class
does not yet exist at the time the Policy is initialized (see below).
The policy for a Java runtime (specifying
which permissions are available for code from various principals)
is represented by a Policy object.
Whenever a Policy is initialized or refreshed, Permission objects of
appropriate classes are created for all permissions
allowed by the Policy.
Many permission class types
referenced by the policy configuration are ones that exist
locally (i.e., ones that can be found on CLASSPATH).
Objects for such permissions can be instantiated during
Policy initialization. For example, it is always possible
to instantiate a java.io.FilePermission, since the
FilePermission class is found on the CLASSPATH.
Other permission classes may not yet exist during Policy
initialization. For example, a referenced permission class may
be in a JAR file that will later be loaded.
For each such class, an UnresolvedPermission is instantiated.
Thus, an UnresolvedPermission is essentially a "placeholder"
containing information about the permission.
Later, when code calls AccessController.checkPermission
on a permission of a type that was previously unresolved,
but whose class has since been loaded, previously-unresolved
permissions of that type are "resolved". That is,
for each such UnresolvedPermission, a new object of
the appropriate class type is instantiated, based on the
information in the UnresolvedPermission.
 To instantiate the new class, UnresolvedPermission assumes the class provides a zero, one, and/or two-argument constructor. The zero-argument constructor would be used to instantiate a permission without a name and without actions. A one-arg constructor is assumed to take a String name as input, and a two-arg constructor is assumed to take a String name and String actions as input. UnresolvedPermission may invoke a constructor with a null name and/or actions. If an appropriate permission constructor is not available, the UnresolvedPermission is ignored and the relevant permission will not be granted to executing code. 
 The newly created permission object replaces the
UnresolvedPermission, which is removed.
 Note that the getName method for an UnresolvedPermission returns the type (class name) for the underlying permission that has not been resolved. 
Author:
Roland Schemers
See Also:
Permission
Permissions
PermissionCollection
Policy
Since:
1.2/**
 * The UnresolvedPermission class is used to hold Permissions that
 * were "unresolved" when the Policy was initialized.
 * An unresolved permission is one whose actual Permission class
 * does not yet exist at the time the Policy is initialized (see below).
 *
 * <p>The policy for a Java runtime (specifying
 * which permissions are available for code from various principals)
 * is represented by a Policy object.
 * Whenever a Policy is initialized or refreshed, Permission objects of
 * appropriate classes are created for all permissions
 * allowed by the Policy.
 *
 * <p>Many permission class types
 * referenced by the policy configuration are ones that exist
 * locally (i.e., ones that can be found on CLASSPATH).
 * Objects for such permissions can be instantiated during
 * Policy initialization. For example, it is always possible
 * to instantiate a java.io.FilePermission, since the
 * FilePermission class is found on the CLASSPATH.
 *
 * <p>Other permission classes may not yet exist during Policy
 * initialization. For example, a referenced permission class may
 * be in a JAR file that will later be loaded.
 * For each such class, an UnresolvedPermission is instantiated.
 * Thus, an UnresolvedPermission is essentially a "placeholder"
 * containing information about the permission.
 *
 * <p>Later, when code calls AccessController.checkPermission
 * on a permission of a type that was previously unresolved,
 * but whose class has since been loaded, previously-unresolved
 * permissions of that type are "resolved". That is,
 * for each such UnresolvedPermission, a new object of
 * the appropriate class type is instantiated, based on the
 * information in the UnresolvedPermission.
 *
 * <p> To instantiate the new class, UnresolvedPermission assumes
 * the class provides a zero, one, and/or two-argument constructor.
 * The zero-argument constructor would be used to instantiate
 * a permission without a name and without actions.
 * A one-arg constructor is assumed to take a {@code String}
 * name as input, and a two-arg constructor is assumed to take a
 * {@code String} name and {@code String} actions
 * as input.  UnresolvedPermission may invoke a
 * constructor with a {@code null} name and/or actions.
 * If an appropriate permission constructor is not available,
 * the UnresolvedPermission is ignored and the relevant permission
 * will not be granted to executing code.
 *
 * <p> The newly created permission object replaces the
 * UnresolvedPermission, which is removed.
 *
 * <p> Note that the {@code getName} method for an
 * {@code UnresolvedPermission} returns the
 * {@code type} (class name) for the underlying permission
 * that has not been resolved.
 *
 * @see java.security.Permission
 * @see java.security.Permissions
 * @see java.security.PermissionCollection
 * @see java.security.Policy
 *
 *
 * @author Roland Schemers
 * @since 1.2
 */

public final class UnresolvedPermission extends Permission
implements java.io.Serializable
{

    private static final long serialVersionUID = -4821973115467008846L;

    private static final sun.security.util.Debug debug =
        sun.security.util.Debug.getInstance
        ("policy,access", "UnresolvedPermission");

    
The class name of the Permission class that will be
created when this unresolved permission is resolved.
@serial
/**
     * The class name of the Permission class that will be
     * created when this unresolved permission is resolved.
     *
     * @serial
     */
    private String type;

    
The permission name.
@serial
/**
     * The permission name.
     *
     * @serial
     */
    private String name;

    
The actions of the permission.
@serial
/**
     * The actions of the permission.
     *
     * @serial
     */
    private String actions;

    private transient java.security.cert.Certificate[] certs;

    
Creates a new UnresolvedPermission containing the permission
information needed later to actually create a Permission of the
specified class, when the permission is resolved.
Params:
type – the class name of the Permission class that will be
created when this unresolved permission is resolved.
name – the name of the permission.
actions – the actions of the permission.
certs – the certificates the permission's class was signed with.
This is a list of certificate chains, where each chain is composed of a
signer certificate and optionally its supporting certificate chain.
Each chain is ordered bottom-to-top (i.e., with the signer certificate
first and the (root) certificate authority last). The signer
certificates are copied from the array. Subsequent changes to
the array will not affect this UnsolvedPermission./**
     * Creates a new UnresolvedPermission containing the permission
     * information needed later to actually create a Permission of the
     * specified class, when the permission is resolved.
     *
     * @param type the class name of the Permission class that will be
     * created when this unresolved permission is resolved.
     * @param name the name of the permission.
     * @param actions the actions of the permission.
     * @param certs the certificates the permission's class was signed with.
     * This is a list of certificate chains, where each chain is composed of a
     * signer certificate and optionally its supporting certificate chain.
     * Each chain is ordered bottom-to-top (i.e., with the signer certificate
     * first and the (root) certificate authority last). The signer
     * certificates are copied from the array. Subsequent changes to
     * the array will not affect this UnsolvedPermission.
     */
    public UnresolvedPermission(String type,
                                String name,
                                String actions,
                                java.security.cert.Certificate[] certs)
    {
        super(type);

        if (type == null)
                throw new NullPointerException("type can't be null");

        this.type = type;
        this.name = name;
        this.actions = actions;
        if (certs != null) {
            // Extract the signer certs from the list of certificates.
            for (int i=0; i<certs.length; i++) {
                if (!(certs[i] instanceof X509Certificate)) {
                    // there is no concept of signer certs, so we store the
                    // entire cert array
                    this.certs = certs.clone();
                    break;
                }
            }

            if (this.certs == null) {
                // Go through the list of certs and see if all the certs are
                // signer certs.
                int i = 0;
                int count = 0;
                while (i < certs.length) {
                    count++;
                    while (((i+1) < certs.length) &&
                           ((X509Certificate)certs[i]).getIssuerDN().equals(
                               ((X509Certificate)certs[i+1]).getSubjectDN())) {
                        i++;
                    }
                    i++;
                }
                if (count == certs.length) {
                    // All the certs are signer certs, so we store the entire
                    // array
                    this.certs = certs.clone();
                }

                if (this.certs == null) {
                    // extract the signer certs
                    ArrayList<java.security.cert.Certificate> signerCerts =
                        new ArrayList<>();
                    i = 0;
                    while (i < certs.length) {
                        signerCerts.add(certs[i]);
                        while (((i+1) < certs.length) &&
                            ((X509Certificate)certs[i]).getIssuerDN().equals(
                              ((X509Certificate)certs[i+1]).getSubjectDN())) {
                            i++;
                        }
                        i++;
                    }
                    this.certs =
                        new java.security.cert.Certificate[signerCerts.size()];
                    signerCerts.toArray(this.certs);
                }
            }
        }
    }


    private static final Class<?>[] PARAMS0 = { };
    private static final Class<?>[] PARAMS1 = { String.class };
    private static final Class<?>[] PARAMS2 = { String.class, String.class };

    
try and resolve this permission using the class loader of the permission
that was passed in.
/**
     * try and resolve this permission using the class loader of the permission
     * that was passed in.
     */
    Permission resolve(Permission p, java.security.cert.Certificate[] certs) {
        if (this.certs != null) {
            // if p wasn't signed, we don't have a match
            if (certs == null) {
                return null;
            }

            // all certs in this.certs must be present in certs
            boolean match;
            for (int i = 0; i < this.certs.length; i++) {
                match = false;
                for (int j = 0; j < certs.length; j++) {
                    if (this.certs[i].equals(certs[j])) {
                        match = true;
                        break;
                    }
                }
                if (!match) return null;
            }
        }
        try {
            Class<?> pc = p.getClass();

            if (name == null && actions == null) {
                try {
                    Constructor<?> c = pc.getConstructor(PARAMS0);
                    return (Permission)c.newInstance(new Object[] {});
                } catch (NoSuchMethodException ne) {
                    try {
                        Constructor<?> c = pc.getConstructor(PARAMS1);
                        return (Permission) c.newInstance(
                              new Object[] { name});
                    } catch (NoSuchMethodException ne1) {
                        Constructor<?> c = pc.getConstructor(PARAMS2);
                        return (Permission) c.newInstance(
                              new Object[] { name, actions });
                    }
                }
            } else {
                if (name != null && actions == null) {
                    try {
                        Constructor<?> c = pc.getConstructor(PARAMS1);
                        return (Permission) c.newInstance(
                              new Object[] { name});
                    } catch (NoSuchMethodException ne) {
                        Constructor<?> c = pc.getConstructor(PARAMS2);
                        return (Permission) c.newInstance(
                              new Object[] { name, actions });
                    }
                } else {
                    Constructor<?> c = pc.getConstructor(PARAMS2);
                    return (Permission) c.newInstance(
                          new Object[] { name, actions });
                }
            }
        } catch (NoSuchMethodException nsme) {
            if (debug != null ) {
                debug.println("NoSuchMethodException:\n  could not find " +
                        "proper constructor for " + type);
                nsme.printStackTrace();
            }
            return null;
        } catch (Exception e) {
            if (debug != null ) {
                debug.println("unable to instantiate " + name);
                e.printStackTrace();
            }
            return null;
        }
    }

    
This method always returns false for unresolved permissions.
That is, an UnresolvedPermission is never considered to
imply another permission.
Params:
p – the permission to check against.
Returns:
false./**
     * This method always returns false for unresolved permissions.
     * That is, an UnresolvedPermission is never considered to
     * imply another permission.
     *
     * @param p the permission to check against.
     *
     * @return false.
     */
    public boolean implies(Permission p) {
        return false;
    }

    
Checks two UnresolvedPermission objects for equality. Checks that obj is an UnresolvedPermission, and has the same type (class) name, permission name, actions, and certificates as this object. 
 To determine certificate equality, this method only compares
actual signer certificates.  Supporting certificate chains
are not taken into consideration by this method.
Params:
obj – the object we are testing for equality with this object.
Returns:
true if obj is an UnresolvedPermission, and has the same
type (class) name, permission name, actions, and
certificates as this object./**
     * Checks two UnresolvedPermission objects for equality.
     * Checks that {@code obj} is an UnresolvedPermission, and has
     * the same type (class) name, permission name, actions, and
     * certificates as this object.
     *
     * <p> To determine certificate equality, this method only compares
     * actual signer certificates.  Supporting certificate chains
     * are not taken into consideration by this method.
     *
     * @param obj the object we are testing for equality with this object.
     *
     * @return true if obj is an UnresolvedPermission, and has the same
     * type (class) name, permission name, actions, and
     * certificates as this object.
     */
    public boolean equals(Object obj) {
        if (obj == this)
            return true;

        if (! (obj instanceof UnresolvedPermission))
            return false;
        UnresolvedPermission that = (UnresolvedPermission) obj;

        // check type
        if (!this.type.equals(that.type)) {
            return false;
        }

        // check name
        if (this.name == null) {
            if (that.name != null) {
                return false;
            }
        } else if (!this.name.equals(that.name)) {
            return false;
        }

        // check actions
        if (this.actions == null) {
            if (that.actions != null) {
                return false;
            }
        } else {
            if (!this.actions.equals(that.actions)) {
                return false;
            }
        }

        // check certs
        if ((this.certs == null && that.certs != null) ||
            (this.certs != null && that.certs == null) ||
            (this.certs != null && that.certs != null &&
                this.certs.length != that.certs.length)) {
            return false;
        }

        int i,j;
        boolean match;

        for (i = 0; this.certs != null && i < this.certs.length; i++) {
            match = false;
            for (j = 0; j < that.certs.length; j++) {
                if (this.certs[i].equals(that.certs[j])) {
                    match = true;
                    break;
                }
            }
            if (!match) return false;
        }

        for (i = 0; that.certs != null && i < that.certs.length; i++) {
            match = false;
            for (j = 0; j < this.certs.length; j++) {
                if (that.certs[i].equals(this.certs[j])) {
                    match = true;
                    break;
                }
            }
            if (!match) return false;
        }
        return true;
    }

    
Returns the hash code value for this object.
Returns:
a hash code value for this object./**
     * Returns the hash code value for this object.
     *
     * @return a hash code value for this object.
     */

    public int hashCode() {
        int hash = type.hashCode();
        if (name != null)
            hash ^= name.hashCode();
        if (actions != null)
            hash ^= actions.hashCode();
        return hash;
    }

    
Returns the canonical string representation of the actions,
which currently is the empty string "", since there are no actions for
an UnresolvedPermission. That is, the actions for the
permission that will be created when this UnresolvedPermission
is resolved may be non-null, but an UnresolvedPermission
itself is never considered to have any actions.
Returns:
the empty string ""./**
     * Returns the canonical string representation of the actions,
     * which currently is the empty string "", since there are no actions for
     * an UnresolvedPermission. That is, the actions for the
     * permission that will be created when this UnresolvedPermission
     * is resolved may be non-null, but an UnresolvedPermission
     * itself is never considered to have any actions.
     *
     * @return the empty string "".
     */
    public String getActions()
    {
        return "";
    }

    
Get the type (class name) of the underlying permission that
has not been resolved.
Returns:
the type (class name) of the underlying permission that
 has not been resolved
Since:
1.5/**
     * Get the type (class name) of the underlying permission that
     * has not been resolved.
     *
     * @return the type (class name) of the underlying permission that
     *  has not been resolved
     *
     * @since 1.5
     */
    public String getUnresolvedType() {
        return type;
    }

    
Get the target name of the underlying permission that
has not been resolved.
Returns:
the target name of the underlying permission that has not been resolved, or null, if there is no target name
Since:
1.5/**
     * Get the target name of the underlying permission that
     * has not been resolved.
     *
     * @return the target name of the underlying permission that
     *          has not been resolved, or {@code null},
     *          if there is no target name
     *
     * @since 1.5
     */
    public String getUnresolvedName() {
        return name;
    }

    
Get the actions for the underlying permission that
has not been resolved.
Returns:
the actions for the underlying permission that has not been resolved, or null if there are no actions
Since:
1.5/**
     * Get the actions for the underlying permission that
     * has not been resolved.
     *
     * @return the actions for the underlying permission that
     *          has not been resolved, or {@code null}
     *          if there are no actions
     *
     * @since 1.5
     */
    public String getUnresolvedActions() {
        return actions;
    }

    
Get the signer certificates (without any supporting chain)
for the underlying permission that has not been resolved.
Returns:
the signer certificates for the underlying permission that
has not been resolved, or null, if there are no signer certificates.
Returns a new array each time this method is called.
Since:
1.5/**
     * Get the signer certificates (without any supporting chain)
     * for the underlying permission that has not been resolved.
     *
     * @return the signer certificates for the underlying permission that
     * has not been resolved, or null, if there are no signer certificates.
     * Returns a new array each time this method is called.
     *
     * @since 1.5
     */
    public java.security.cert.Certificate[] getUnresolvedCerts() {
        return (certs == null) ? null : certs.clone();
    }

    
Returns a string describing this UnresolvedPermission.  The convention
is to specify the class name, the permission name, and the actions, in
the following format: '(unresolved "ClassName" "name" "actions")'.
Returns:
information about this UnresolvedPermission./**
     * Returns a string describing this UnresolvedPermission.  The convention
     * is to specify the class name, the permission name, and the actions, in
     * the following format: '(unresolved "ClassName" "name" "actions")'.
     *
     * @return information about this UnresolvedPermission.
     */
    public String toString() {
        return "(unresolved " + type + " " + name + " " + actions + ")";
    }

    
Returns a new PermissionCollection object for storing
UnresolvedPermission  objects.
Returns:
a new PermissionCollection object suitable for
storing UnresolvedPermissions./**
     * Returns a new PermissionCollection object for storing
     * UnresolvedPermission  objects.
     *
     * @return a new PermissionCollection object suitable for
     * storing UnresolvedPermissions.
     */

    public PermissionCollection newPermissionCollection() {
        return new UnresolvedPermissionCollection();
    }

    
Writes this object out to a stream (i.e., serializes it).
@serialData
An initial String denoting the type is followed by a String denoting the name is followed by a String denoting the actions is followed by an int indicating the number of certificates to follow (a value of "zero" denotes that there are no certificates associated with this object). Each certificate is written out starting with a String denoting the certificate type, followed by an int specifying the length of the certificate encoding, followed by the certificate encoding itself which is written out as an array of bytes./**
     * Writes this object out to a stream (i.e., serializes it).
     *
     * @serialData An initial {@code String} denoting the
     * {@code type} is followed by a {@code String} denoting the
     * {@code name} is followed by a {@code String} denoting the
     * {@code actions} is followed by an {@code int} indicating the
     * number of certificates to follow
     * (a value of "zero" denotes that there are no certificates associated
     * with this object).
     * Each certificate is written out starting with a {@code String}
     * denoting the certificate type, followed by an
     * {@code int} specifying the length of the certificate encoding,
     * followed by the certificate encoding itself which is written out as an
     * array of bytes.
     */
    private void writeObject(java.io.ObjectOutputStream oos)
        throws IOException
    {
        oos.defaultWriteObject();

        if (certs==null || certs.length==0) {
            oos.writeInt(0);
        } else {
            // write out the total number of certs
            oos.writeInt(certs.length);
            // write out each cert, including its type
            for (int i=0; i < certs.length; i++) {
                java.security.cert.Certificate cert = certs[i];
                try {
                    oos.writeUTF(cert.getType());
                    byte[] encoded = cert.getEncoded();
                    oos.writeInt(encoded.length);
                    oos.write(encoded);
                } catch (CertificateEncodingException cee) {
                    throw new IOException(cee.getMessage());
                }
            }
        }
    }

    
Restores this object from a stream (i.e., deserializes it).
/**
     * Restores this object from a stream (i.e., deserializes it).
     */
    private void readObject(java.io.ObjectInputStream ois)
        throws IOException, ClassNotFoundException
    {
        CertificateFactory cf;
        Hashtable<String, CertificateFactory> cfs = null;
        List<Certificate> certList = null;

        ois.defaultReadObject();

        if (type == null)
                throw new NullPointerException("type can't be null");

        // process any new-style certs in the stream (if present)
        int size = ois.readInt();
        if (size > 0) {
            // we know of 3 different cert types: X.509, PGP, SDSI, which
            // could all be present in the stream at the same time
            cfs = new Hashtable<>(3);
            certList = new ArrayList<>(size > 20 ? 20 : size);
        } else if (size < 0) {
            throw new IOException("size cannot be negative");
        }

        for (int i=0; i<size; i++) {
            // read the certificate type, and instantiate a certificate
            // factory of that type (reuse existing factory if possible)
            String certType = ois.readUTF();
            if (cfs.containsKey(certType)) {
                // reuse certificate factory
                cf = cfs.get(certType);
            } else {
                // create new certificate factory
                try {
                    cf = CertificateFactory.getInstance(certType);
                } catch (CertificateException ce) {
                    throw new ClassNotFoundException
                        ("Certificate factory for "+certType+" not found");
                }
                // store the certificate factory so we can reuse it later
                cfs.put(certType, cf);
            }
            // parse the certificate
            byte[] encoded = IOUtils.readExactlyNBytes(ois, ois.readInt());
            ByteArrayInputStream bais = new ByteArrayInputStream(encoded);
            try {
                certList.add(cf.generateCertificate(bais));
            } catch (CertificateException ce) {
                throw new IOException(ce.getMessage());
            }
            bais.close();
        }
        if (certList != null) {
            this.certs = certList.toArray(
                    new java.security.cert.Certificate[size]);
        }
    }
}