/*

 * Copyright 1997-2006 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package java.net;

import java.util.Enumeration;

import java.util.Vector;

import java.util.List;

import java.util.ArrayList;

import java.util.Collections;

import java.util.StringTokenizer;

import java.net.InetAddress;

import java.security.Permission;

import java.security.PermissionCollection;

import java.io.Serializable;

import java.io.ObjectStreamField;

import java.io.ObjectOutputStream;

import java.io.ObjectInputStream;

import java.io.IOException;

import sun.net.util.IPAddressUtil;

import sun.security.util.SecurityConstants;

/**

 * This class represents access to a network via sockets.

 * A SocketPermission consists of a

 * host specification and a set of "actions" specifying ways to

 * connect to that host. The host is specified as

 * <pre>

 *    host = (hostname | IPv4address | iPv6reference) [:portrange]

 *    portrange = portnumber | -portnumber | portnumber-[portnumber]

 * </pre>

 * The host is expressed as a DNS name, as a numerical IP address,

 * or as "localhost" (for the local machine).

 * The wildcard "*" may be included once in a DNS name host

 * specification. If it is included, it must be in the leftmost

 * position, as in "*.sun.com".

 * <p>

 * The format of the IPv6reference should follow that specified in <a

 * href="http://www.ietf.org/rfc/rfc2732.txt"><i>RFC&nbsp;2732: Format

 * for Literal IPv6 Addresses in URLs</i></a>:

 * <pre>

 *    ipv6reference = "[" IPv6address "]"

 *</pre>

 * For example, you can construct a SocketPermission instance

 * as the following:

 * <pre>

 *    String hostAddress = inetaddress.getHostAddress();

 *    if (inetaddress instanceof Inet6Address) {

 *        sp = new SocketPermission("[" + hostAddress + "]:" + port, action);

 *    } else {

 *        sp = new SocketPermission(hostAddress + ":" + port, action);

 *    }

 * </pre>

 * or

 * <pre>

 *    String host = url.getHost();

 *    sp = new SocketPermission(host + ":" + port, action);

 * </pre>

 * <p>

 * The <A HREF="Inet6Address.html#lform">full uncompressed form</A> of

 * an IPv6 literal address is also valid.

 * <p>

 * The port or portrange is optional. A port specification of the

 * form "N-", where <i>N</i> is a port number, signifies all ports

 * numbered <i>N</i> and above, while a specification of the

 * form "-N" indicates all ports numbered <i>N</i> and below.

 * <p>

 * The possible ways to connect to the host are

 * <pre>

 * accept

 * connect

 * listen

 * resolve

 * </pre>

 * The "listen" action is only meaningful when used with "localhost".

 * The "resolve" action is implied when any of the other actions are present.

 * The action "resolve" refers to host/ip name service lookups.

 * <P>

 * The actions string is converted to lowercase before processing.

 * <p>As an example of the creation and meaning of SocketPermissions,

 * note that if the following permission:

 *

 * <pre>

 *   p1 = new SocketPermission("puffin.eng.sun.com:7777", "connect,accept");

 * </pre>

 *

 * is granted to some code, it allows that code to connect to port 7777 on

 * <code>puffin.eng.sun.com</code>, and to accept connections on that port.

 *

 * <p>Similarly, if the following permission:

 *

 * <pre>

 *   p1 = new SocketPermission("puffin.eng.sun.com:7777", "connect,accept");

 *   p2 = new SocketPermission("localhost:1024-", "accept,connect,listen");

 * </pre>

 *

 * is granted to some code, it allows that code to

 * accept connections on, connect to, or listen on any port between

 * 1024 and 65535 on the local host.

 *

 * <p>Note: Granting code permission to accept or make connections to remote

 * hosts may be dangerous because malevolent code can then more easily

 * transfer and share confidential data among parties who may not

 * otherwise have access to the data.

 *

 * @see java.security.Permissions

 * @see SocketPermission

 *

 *

 * @author Marianne Mueller

 * @author Roland Schemers

 *

 * @serial exclude

 */

public final class SocketPermission extends Permission

implements java.io.Serializable

{

    private static final long serialVersionUID = -7204263841984476862L;

    /**

     * Connect to host:port

     */

    private final static int CONNECT    = 0x1;

    /**

     * Listen on host:port

     */

    private final static int LISTEN     = 0x2;

    /**

     * Accept a connection from host:port

     */

    private final static int ACCEPT     = 0x4;

    /**

     * Resolve DNS queries

     */

    private final static int RESOLVE    = 0x8;

    /**

     * No actions

     */

    private final static int NONE               = 0x0;

    /**

     * All actions

     */

    private final static int ALL        = CONNECT|LISTEN|ACCEPT|RESOLVE;

    // various port constants

    private static final int PORT_MIN = 0;

    private static final int PORT_MAX = 65535;

    private static final int PRIV_PORT_MAX = 1023;

    // 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.

    // hostname part as it is passed

    private transient String hostname;

    // the canonical name of the host

    // in the case of "*.foo.com", cname is ".foo.com".

    private transient String cname;

    // all the IP addresses of the host

    private transient InetAddress[] addresses;

    // true if the hostname is a wildcard (e.g. "*.sun.com")

    private transient boolean wildcard;

    // true if we were initialized with a single numeric IP address

    private transient boolean init_with_ip;

    // true if this SocketPermission represents an invalid/unknown host

    // used for implies when the delayed lookup has already failed

    private transient boolean invalid;

    // port range on host

    private transient int[] portrange;

    // true if the trustProxy system property is set

    private static boolean trustProxy;

    static {

        Boolean tmp = java.security.AccessController.doPrivileged(

                new sun.security.action.GetBooleanAction("trustProxy"));

        trustProxy = tmp.booleanValue();

    }

    /**

     * Creates a new SocketPermission object with the specified actions.

     * The host is expressed as a DNS name, or as a numerical IP address.

     * Optionally, a port or a portrange may be supplied (separated

     * from the DNS name or IP address by a colon).

     * <p>

     * To specify the local machine, use "localhost" as the <i>host</i>.

     * Also note: An empty <i>host</i> String ("") is equivalent to "localhost".

     * <p>

     * The <i>actions</i> parameter contains a comma-separated list of the

     * actions granted for the specified host (and port(s)). Possible actions are

     * "connect", "listen", "accept", "resolve", or

     * any combination of those. "resolve" is automatically added

     * when any of the other three are specified.

     * <p>

     * Examples of SocketPermission instantiation are the following:

     * <pre>

     *    nr = new SocketPermission("www.catalog.com", "connect");

     *    nr = new SocketPermission("www.sun.com:80", "connect");

     *    nr = new SocketPermission("*.sun.com", "connect");

     *    nr = new SocketPermission("*.edu", "resolve");

     *    nr = new SocketPermission("204.160.241.0", "connect");

     *    nr = new SocketPermission("localhost:1024-65535", "listen");

     *    nr = new SocketPermission("204.160.241.0:1024-65535", "connect");

     * </pre>

     *

     * @param host the hostname or IPaddress of the computer, optionally

     * including a colon followed by a port or port range.

     * @param action the action string.

     */

    public SocketPermission(String host, String action) {

        super(getHost(host));

        // name initialized to getHost(host); NPE detected in getHost()

        init(getName(), getMask(action));

    }

    SocketPermission(String host, int mask) {

        super(getHost(host));

        // name initialized to getHost(host); NPE detected in getHost()

        init(getName(), mask);

    }

    private static String getHost(String host)

    {

        if (host.equals("")) {

            return "localhost";

        } else {

            /* IPv6 literal address used in this context should follow

             * the format specified in RFC 2732;

             * if not, we try to solve the unambiguous case

             */

            int ind;

            if (host.charAt(0) != '[') {

                if ((ind = host.indexOf(':')) != host.lastIndexOf(':')) {

                    /* More than one ":", meaning IPv6 address is not

                     * in RFC 2732 format;

                     * We will rectify user errors for all unambiguious cases

                     */

                    StringTokenizer st = new StringTokenizer(host, ":");

                    int tokens = st.countTokens();

                    if (tokens == 9) {

                        // IPv6 address followed by port

                        ind = host.lastIndexOf(':');

                        host = "[" + host.substring(0, ind) + "]" +

                            host.substring(ind);

                    } else if (tokens == 8 && host.indexOf("::") == -1) {

                        // IPv6 address only, not followed by port

                        host = "[" + host + "]";

                    } else {

                        // could be ambiguous

                        throw new IllegalArgumentException("Ambiguous"+

                                                           " hostport part");

                    }

                }

            }

            return host;

        }

    }

    private int[] parsePort(String port)

        throws Exception

    {

        if (port == null || port.equals("") || port.equals("*")) {

            return new int[] {PORT_MIN, PORT_MAX};

        }

        int dash = port.indexOf('-');

        if (dash == -1) {

            int p = Integer.parseInt(port);

            return new int[] {p, p};

        } else {

            String low = port.substring(0, dash);

            String high = port.substring(dash+1);

            int l,h;

            if (low.equals("")) {

                l = PORT_MIN;

            } else {

                l = Integer.parseInt(low);

            }

            if (high.equals("")) {

                h = PORT_MAX;

            } else {

                h = Integer.parseInt(high);

            }

            if (l < 0 || h < 0 || h<l)

                throw new IllegalArgumentException("invalid port range");

            return new int[] {l, h};

        }

    }

    /**

     * Initialize the SocketPermission object. We don't do any DNS lookups

     * as this point, instead we hold off until the implies method is

     * called.

     */

    private void init(String host, int mask) {

        // Set the integer mask that represents the actions

        if ((mask & ALL) != mask)

            throw new IllegalArgumentException("invalid actions mask");

        // always OR in RESOLVE if we allow any of the others

        this.mask = mask | RESOLVE;

        // Parse the host name.  A name has up to three components, the

        // hostname, a port number, or two numbers representing a port

        // range.   "www.sun.com:8080-9090" is a valid host name.

        // With IPv6 an address can be 2010:836B:4179::836B:4179

        // An IPv6 address needs to be enclose in []

        // For ex: [2010:836B:4179::836B:4179]:8080-9090

        // Refer to RFC 2732 for more information.

        int rb = 0 ;

        int start = 0, end = 0;

        int sep = -1;

        String hostport = host;

        if (host.charAt(0) == '[') {

            start = 1;

            rb = host.indexOf(']');

            if (rb != -1) {

                host = host.substring(start, rb);

            } else {

                throw new

                    IllegalArgumentException("invalid host/port: "+host);

            }

            sep = hostport.indexOf(':', rb+1);

        } else {

            start = 0;

            sep = host.indexOf(':', rb);

            end = sep;

            if (sep != -1) {

                host = host.substring(start, end);

            }

        }

        if (sep != -1) {

            String port = hostport.substring(sep+1);

            try {

                portrange = parsePort(port);

            } catch (Exception e) {

                throw new

                    IllegalArgumentException("invalid port range: "+port);

            }

        } else {

            portrange = new int[] { PORT_MIN, PORT_MAX };

        }

        hostname = host;

        // is this a domain wildcard specification

        if (host.lastIndexOf('*') > 0) {

            throw new

               IllegalArgumentException("invalid host wildcard specification");

        } else if (host.startsWith("*")) {

            wildcard = true;

            if (host.equals("*")) {

                cname = "";

            } else if (host.startsWith("*.")) {

                cname = host.substring(1).toLowerCase();

            } else {

              throw new

               IllegalArgumentException("invalid host wildcard specification");

            }

            return;

        } else {

            if (host.length() > 0) {

                // see if we are being initialized with an IP address.

                char ch = host.charAt(0);

                if (ch == ':' || Character.digit(ch, 16) != -1) {

                    byte ip[] = IPAddressUtil.textToNumericFormatV4(host);

                    if (ip == null) {

                        ip = IPAddressUtil.textToNumericFormatV6(host);

                    }

                    if (ip != null) {

                        try {

                            addresses =

                                new InetAddress[]

                                {InetAddress.getByAddress(ip) };

                            init_with_ip = true;

                        } catch (UnknownHostException uhe) {

                            // this shouldn't happen

                            invalid = true;

                        }

                    }

                }

            }

        }

    }

    /**

     * Convert an action string to an integer actions mask.

     *

     * @param action the action string

     * @return the action mask

     */

    private static int getMask(String action) {

        if (action == null) {

            throw new NullPointerException("action can't be null");

        }

        if (action.equals("")) {

            throw new IllegalArgumentException("action can't be empty");

        }

        int mask = NONE;

        // Check against use of constants (used heavily within the JDK)

        if (action == SecurityConstants.SOCKET_RESOLVE_ACTION) {

            return RESOLVE;

        } else if (action == SecurityConstants.SOCKET_CONNECT_ACTION) {

            return CONNECT;

        } else if (action == SecurityConstants.SOCKET_LISTEN_ACTION) {

            return LISTEN;

        } else if (action == SecurityConstants.SOCKET_ACCEPT_ACTION) {

            return ACCEPT;

        } else if (action == SecurityConstants.SOCKET_CONNECT_ACCEPT_ACTION) {

            return CONNECT|ACCEPT;

        }

        char[] a = action.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 >= 6 && (a[i-6] == 'c' || a[i-6] == 'C') &&

                          (a[i-5] == 'o' || a[i-5] == 'O') &&

                          (a[i-4] == 'n' || a[i-4] == 'N') &&

                          (a[i-3] == 'n' || a[i-3] == 'N') &&

                          (a[i-2] == 'e' || a[i-2] == 'E') &&

                          (a[i-1] == 'c' || a[i-1] == 'C') &&

                          (a[i] == 't' || a[i] == 'T'))

            {

                matchlen = 7;

                mask |= CONNECT;

            } else if (i >= 6 && (a[i-6] == 'r' || a[i-6] == 'R') &&

                                 (a[i-5] == 'e' || a[i-5] == 'E') &&

                                 (a[i-4] == 's' || a[i-4] == 'S') &&

                                 (a[i-3] == 'o' || a[i-3] == 'O') &&

                                 (a[i-2] == 'l' || a[i-2] == 'L') &&

                                 (a[i-1] == 'v' || a[i-1] == 'V') &&

                                 (a[i] == 'e' || a[i] == 'E'))

            {

                matchlen = 7;

                mask |= RESOLVE;

            } else if (i >= 5 && (a[i-5] == 'l' || a[i-5] == 'L') &&

                                 (a[i-4] == 'i' || a[i-4] == 'I') &&

                                 (a[i-3] == 's' || a[i-3] == 'S') &&

                                 (a[i-2] == 't' || a[i-2] == 'T') &&

                                 (a[i-1] == 'e' || a[i-1] == 'E') &&

                                 (a[i] == 'n' || a[i] == 'N'))

            {

                matchlen = 6;

                mask |= LISTEN;

            } else if (i >= 5 && (a[i-5] == 'a' || a[i-5] == 'A') &&

                                 (a[i-4] == 'c' || a[i-4] == 'C') &&

                                 (a[i-3] == 'c' || a[i-3] == 'C') &&

                                 (a[i-2] == 'e' || a[i-2] == 'E') &&

                                 (a[i-1] == 'p' || a[i-1] == 'P') &&

                                 (a[i] == 't' || a[i] == 'T'))