Source for gnu.javax.net.ssl.provider.Record

   1: /* Record.java -- A single SSL Record.
   2:    Copyright (C) 2006  Free Software Foundation, Inc.
   3: 
   4: This file is a part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2 of the License, or (at
   9: your option) any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; if not, write to the Free Software
  18: Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
  19: USA
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version.  */
  37: 
  38: 
  39: package gnu.javax.net.ssl.provider;
  40: 
  41: import java.io.PrintWriter;
  42: import java.io.StringWriter;
  43: import java.nio.ByteBuffer;
  44: import java.nio.ByteOrder;
  45: 
  46: /**
  47:  * A SSL/TLS record structure. An SSL record is defined to be:
  48:  *
  49:  * <pre>
  50: struct
  51: {
  52:   {@link ContentType}     type;
  53:   {@link ProtocolVersion} version;
  54:   uint16          length;
  55:   opaque          fragment[TLSPlaintext.length];
  56: } TLSPlaintext;
  57: </pre>
  58:  */
  59: public class Record
  60: {
  61:   private final ByteBuffer buffer;
  62: 
  63:   public Record (final ByteBuffer buffer)
  64:   {
  65:     this.buffer = buffer.duplicate().order(ByteOrder.BIG_ENDIAN);
  66:   }
  67: 
  68:   // XXX remove
  69:   public ContentType getContentType ()
  70:   {
  71:     return contentType ();
  72:   }
  73: 
  74:   /**
  75:    * Gets the content type field.
  76:    *
  77:    * @return The content type field.
  78:    */
  79:   public ContentType contentType ()
  80:   {
  81:     return ContentType.forInteger (buffer.get (0) & 0xFF);
  82:   }
  83: 
  84:   /**
  85:    * Get the fragment content, storing it into <code>sink</code>.
  86:    *
  87:    * @param sink The sink for the fragment bytes.
  88:    * @return The number of bytes put into <code>sink</code>
  89:    */
  90:   public int fragment (final ByteBuffer sink)
  91:   {
  92:     int length = length ();
  93:     sink.put (((ByteBuffer) buffer.limit (5 + length).position (5)).slice ());
  94:     return length;
  95:   }
  96: 
  97:   /**
  98:    * Returns the fragment field as a ByteBuffer. The returned buffer
  99:    * is shared with this object's underlying buffer, so it will share
 100:    * its attributes. For example, if the underlying buffer is
 101:    * read-only, the returned buffer will be read-only.
 102:    *
 103:    * @return The fragment buffer.
 104:    */
 105:   public ByteBuffer fragment ()
 106:   {
 107:     int length = length ();
 108:     return ((ByteBuffer) buffer.limit (5 + length).position (5)).slice ();
 109:   }
 110: 
 111:   /**
 112:    * Gets the fragment length.
 113:    *
 114:    * @return The fragment length.
 115:    */
 116:   public int length ()
 117:   {
 118:     // XXX this is different behavior than we usually want: we return the
 119:     // length field, not the total length. We should consider changing this.
 120:     return buffer.getShort (3) & 0xFFFF;
 121:   }
 122: 
 123:   /**
 124:    * Gets the protocol version field.
 125:    *
 126:    * @return The protocol version field.
 127:    */
 128:   public ProtocolVersion version ()
 129:   {
 130:     int major = buffer.get (1) & 0xFF;
 131:     int minor = buffer.get (2) & 0xFF;
 132:     return ProtocolVersion.getInstance (major, minor);
 133:   }
 134: 
 135:   /**
 136:    * Sets the content type field.
 137:    *
 138:    * @param type The content type.
 139:    * @throws java.nio.ReadOnlyBufferException If the underlying buffer
 140:    * is not writeable.
 141:    * @throws NullPointerException If <i>type</i> is <code>null</code>.
 142:    */
 143:   public void setContentType (final ContentType type)
 144:   {
 145:     buffer.put (0, (byte) type.getValue ());
 146:   }
 147: 
 148:   /**
 149:    * Sets the fragment length.
 150:    *
 151:    * @param length The fragment length.
 152:    * @throws java.nio.ReadOnlyBufferException If the underlying buffer
 153:    * is not writeable.
 154:    * @throws IllegalArgumentException If the length is not between 0
 155:    * and 16384, inclusive.
 156:    */
 157:   public void setLength (final int length)
 158:   {
 159:     if (length < 0 || length > 16384)
 160:       throw new IllegalArgumentException ("length " + length + " out of range; "
 161:                                           + "must be between 0 and 16384");
 162:     buffer.putShort (3, (short) length);
 163:   }
 164: 
 165:   /**
 166:    * Sets the protocol version field.
 167:    *
 168:    * @param version The protocol version.
 169:    * @throws java.nio.ReadOnlyBufferException If the underlying buffer
 170:    * is not writeable.
 171:    * @throws NullPointerException If <i>version</i> is <code>null</code>.
 172:    */
 173:   public void setVersion (final ProtocolVersion version)
 174:   {
 175:     buffer.put (1, (byte) version.major ()).put (2, (byte) version.minor ());
 176:   }
 177: 
 178:   public String toString ()
 179:   {
 180:     StringWriter str = new StringWriter ();
 181:     PrintWriter out = new PrintWriter (str);
 182:     out.println ("struct {");
 183:     out.print ("  type:    ");
 184:     out.print (contentType ());
 185:     out.println (";");
 186:     out.print ("  version: ");
 187:     out.print (version ());
 188:     out.println (";");
 189:     out.print("  length: ");
 190:     out.print(length());
 191:     out.println(";");
 192:     out.println ("  fragment {");
 193:     out.print (Util.hexDump (fragment (), "    "));
 194:     out.println ("  };");
 195:     out.print ("} Record;");
 196:     return str.toString ();
 197:   }
 198: }