Connection.java 13.5 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352
/**
 * $RCSfile: Connection.java,v $
 * $Revision: 3187 $
 * $Date: 2005-12-11 13:34:34 -0300 (Sun, 11 Dec 2005) $
 *
 * Copyright (C) 2007 Jive Software. All rights reserved.
 *
 * This software is published under the terms of the GNU Public License (GPL),
 * a copy of which is included in this distribution.
 */

package org.jivesoftware.openfire;

import org.jivesoftware.openfire.auth.UnauthorizedException;
import org.jivesoftware.openfire.session.LocalSession;
import org.xmpp.packet.Packet;

import java.net.UnknownHostException;

/**
 * Represents a connection on the server.
 *
 * @author Iain Shigeoka
 */
public interface Connection {

    /**
     * Verifies that the connection is still live. Typically this is done by
     * sending a whitespace character between packets.
     *
     * @return true if the socket remains valid, false otherwise.
     */
    public boolean validate();

    /**
     * Initializes the connection with it's owning session. Allows the
     * connection class to configure itself with session related information
     * (e.g. stream ID).
     *
     * @param session the session that owns this connection
     */
    public void init(LocalSession session);

    /**
     * Returns the raw IP address of this <code>InetAddress</code>
     * object. The result is in network byte order: the highest order
     * byte of the address is in <code>getAddress()[0]</code>.
     *
     * @return  the raw IP address of this object.
     * @throws java.net.UnknownHostException if IP address of host could not be determined.
     */
    public byte[] getAddress() throws UnknownHostException;

    /**
     * Returns the IP address string in textual presentation.
     *
     * @return  the raw IP address in a string format.
     * @throws java.net.UnknownHostException if IP address of host could not be determined.
     */
    public String getHostAddress() throws UnknownHostException;

    /**
     * Gets the host name for this IP address.
     *
     * <p>If this InetAddress was created with a host name,
     * this host name will be remembered and returned;
     * otherwise, a reverse name lookup will be performed
     * and the result will be returned based on the system
     * configured name lookup service. If a lookup of the name service
     * is required, call
     * {@link java.net.InetAddress#getCanonicalHostName() getCanonicalHostName}.
     *
     * <p>If there is a security manager, its
     * <code>checkConnect</code> method is first called
     * with the hostname and <code>-1</code>
     * as its arguments to see if the operation is allowed.
     * If the operation is not allowed, it will return
     * the textual representation of the IP address.
     *
     * @return  the host name for this IP address, or if the operation
     *    is not allowed by the security check, the textual
     *    representation of the IP address.
     * @throws java.net.UnknownHostException if IP address of host could not be determined.
     *
     * @see java.net.InetAddress#getCanonicalHostName
     * @see SecurityManager#checkConnect
     */
    public String getHostName() throws UnknownHostException;

    /**
     * Close this session including associated socket connection. The order of
     * events for closing the session is:
     * <ul>
     *      <li>Set closing flag to prevent redundant shutdowns.
     *      <li>Call notifyEvent all listeners that the channel is shutting down.
     *      <li>Close the socket.
     * </ul>
     */
    public void close();

    /**
     * Notification message indicating that the server is being shutdown. Implementors
     * should send a stream error whose condition is system-shutdown before closing
     * the connection.
     */
    public void systemShutdown();

    /**
     * Returns true if the connection/session is closed.
     *
     * @return true if the connection is closed.
     */
    public boolean isClosed();

    /**
     * Returns true if this connection is secure.
     *
     * @return true if the connection is secure (e.g. SSL/TLS)
     */
    public boolean isSecure();

    /**
     * Registers a listener for close event notification. Registrations after
     * the Session is closed will be immediately notified <em>before</em>
     * the registration call returns (within the context of the
     * registration call). An optional handback object can be associated with
     * the registration if the same listener is registered to listen for multiple
     * connection closures.
     *
     * @param listener the listener to register for events.
     * @param handbackMessage the object to send in the event notification.
     */
    public void registerCloseListener(ConnectionCloseListener listener, Object handbackMessage);

    /**
     * Removes a registered close event listener. Registered listeners must
     * be able to receive close events up until the time this method returns.
     * (i.e. it is possible to call unregister, receive a close event registration,
     * and then have the unregister call return.)
     *
     * @param listener the listener to deregister for close events.
     */
    public void removeCloseListener(ConnectionCloseListener listener);

    /**
     * Delivers the packet to this connection without checking the recipient.
     * The method essentially calls <code>socket.send(packet.getWriteBuffer())</code>.
     *
     * @param packet the packet to deliver.
     * @throws org.jivesoftware.openfire.auth.UnauthorizedException if a permission error was detected.
     */
    public void deliver(Packet packet) throws UnauthorizedException;

    /**
     * Delivers raw text to this connection. This is a very low level way for sending
     * XML stanzas to the client. This method should not be used unless you have very
     * good reasons for not using {@link #deliver(org.xmpp.packet.Packet)}.<p>
     *
     * This method avoids having to get the writer of this connection and mess directly
     * with the writer. Therefore, this method ensures a correct delivery of the stanza
     * even if other threads were sending data concurrently.
     *
     * @param text the XML stanzas represented kept in a String.
     */
    public void deliverRawText(String text);

    /**
     * Returns true if the connected client is a flash client. Flash clients need
     * to receive a special character (i.e. \0) at the end of each xml packet. Flash
     * clients may send the character \0 in incoming packets and may start a connection
     * using another openning tag such as: "flash:client".
     *
     * @return true if the connected client is a flash client.
     */
    public boolean isFlashClient();

    /**
     * Sets whether the connected client is a flash client. Flash clients need to
     * receive a special character (i.e. \0) at the end of each xml packet. Flash
     * clients may send the character \0 in incoming packets and may start a
     * connection using another openning tag such as: "flash:client".
     *
     * @param flashClient true if the if the connection is a flash client.
     */
    public void setFlashClient(boolean flashClient);

    /**
     * Returns the major version of XMPP being used by this connection
     * (major_version.minor_version. In most cases, the version should be
     * "1.0". However, older clients using the "Jabber" protocol do not set a
     * version. In that case, the version is "0.0".
     *
     * @return the major XMPP version being used by this connection.
     */
    public int getMajorXMPPVersion();

    /**
     * Returns the minor version of XMPP being used by this connection
     * (major_version.minor_version. In most cases, the version should be
     * "1.0". However, older clients using the "Jabber" protocol do not set a
     * version. In that case, the version is "0.0".
     *
     * @return the minor XMPP version being used by this connection.
     */
    public int getMinorXMPPVersion();

    /**
     * Sets the XMPP version information. In most cases, the version should be "1.0".
     * However, older clients using the "Jabber" protocol do not set a version. In that
     * case, the version is "0.0".
     *
     * @param majorVersion the major version.
     * @param minorVersion the minor version.
     */
    public void setXMPPVersion(int majorVersion, int minorVersion);

    /**
     * Returns the language code that should be used for this connection
     * (e.g. "en").
     *
     * @return the language code for the connection.
     */
    public String getLanguage();

    /**
     * Sets the language code that should be used for this connection (e.g. "en").
     *
     * @param language the language code.
     */
    public void setLanaguage(String language);

    /**
     * Returns true if the connection is using compression.
     *
     * @return true if the connection is using compression.
     */
    boolean isCompressed();

    /**
     * Returns whether compression is optional or is disabled.
     *
     * @return whether compression is optional or is disabled.
     */
    CompressionPolicy getCompressionPolicy();

    /**
     * Sets whether compression is enabled or is disabled.
     *
     * @param compressionPolicy whether Compression is enabled or is disabled.
     */
    void setCompressionPolicy(CompressionPolicy compressionPolicy);

    /**
     * Returns whether TLS is mandatory, optional or is disabled. When TLS is mandatory clients
     * are required to secure their connections or otherwise their connections will be closed.
     * On the other hand, when TLS is disabled clients are not allowed to secure their connections
     * using TLS. Their connections will be closed if they try to secure the connection. in this
     * last case.
     *
     * @return whether TLS is mandatory, optional or is disabled.
     */
    TLSPolicy getTlsPolicy();

    /**
     * Sets whether TLS is mandatory, optional or is disabled. When TLS is mandatory clients
     * are required to secure their connections or otherwise their connections will be closed.
     * On the other hand, when TLS is disabled clients are not allowed to secure their connections
     * using TLS. Their connections will be closed if they try to secure the connection. in this
     * last case.
     *
     * @param tlsPolicy whether TLS is mandatory, optional or is disabled.
     */
    void setTlsPolicy(TLSPolicy tlsPolicy);

    /**
     * Returns the packet deliverer to use when delivering a packet over the socket fails. The
     * packet deliverer will retry to send the packet using some other connection, will store
     * the packet offline for later retrieval or will just drop it.
     *
     * @return the packet deliverer to use when delivering a packet over the socket fails.
     */
    PacketDeliverer getPacketDeliverer();

    /**
     * Secures the plain connection by negotiating TLS with the client. When connecting
     * to a remote server then <tt>clientMode</tt> will be <code>true</code> and
     * <tt>remoteServer</tt> is the server name of the remote server. Otherwise <tt>clientMode</tt>
     * will be <code>false</code> and  <tt>remoteServer</tt> null.
     *
     * @param clientMode boolean indicating if this entity is a client or a server.
     * @param remoteServer server name of the remote server we are connecting to or <tt>null</tt>
     *        when not in client mode.
     * @throws Exception if an error occured while securing the connection.
     */
    void startTLS(boolean clientMode, String remoteServer) throws Exception;

    /**
     * Adds the compression filter to the connection but only filter incoming traffic. Do not filter
     * outgoing traffic since we still need to send an uncompressed stanza to the client indicating
     * that he can start compressing the traffic. After we sent the uncompresses stanza we can
     * start compression outgoing traffic as well.
     */
    void addCompression();

    /**
     * Start compressing outgoing traffic for this connection. Compression will only be available after
     * TLS has been negotiated. This means that a connection can never be using compression before
     * TLS. However, it is possible to use compression without TLS.
     */
    void startCompression();

    /**
     * Enumeration of possible compression policies required to interact with the server.
     */
    enum CompressionPolicy {

        /**
         * compression is optional to interact with the server.
         */
        optional,

        /**
         * compression is not available. Entities that request a compression negotiation
         * will get a stream error and their connections will be closed.
         */
        disabled
    }

    /**
     * Enumeration of possible TLS policies required to interact with the server.
     */
    enum TLSPolicy {

        /**
         * TLS is required to interact with the server. Entities that do not secure their
         * connections using TLS will get a stream error and their connections will be closed.
         */
        required,

        /**
         * TLS is optional to interact with the server. Entities may or may not secure their
         * connections using TLS.
         */
        optional,

        /**
         * TLS is not available. Entities that request a TLS negotiation will get a stream
         * error and their connections will be closed.
         */
        disabled
    }
}