path: root/gnu/javax/net/ssl/provider/ServerNameList.java

package gnu.javax.net.ssl.provider;

import gnu.javax.net.ssl.provider.Extension.Value;

import java.io.PrintWriter;
import java.io.StringWriter;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.charset.Charset;
import java.util.NoSuchElementException;

/**
 * The ServerName extension.
 * 
 * <pre>
 struct {
   NameType name_type;
   select (name_type) {
     case host_name: HostName;
   } name;
} ServerName;

enum {
  host_name(0), (255)
} NameType;

opaque HostName<1..2^16-1>;

struct {
  ServerName server_name_list<1..2^16-1>
} ServerNameList;</pre>
 *
 * <p><b>Implementation note: this class does not currently contain a
 * <code>set</code> method. If you are modifying this list, then use the
 * {@link #get(int)} method, and modify the returned {@link ServerName}.
 *
 * @author csm
 */
public class ServerNameList extends Value implements Iterable<ServerNameList.ServerName>
{
  private final ByteBuffer buffer;
  
  public ServerNameList (final ByteBuffer buffer)
  {
    this.buffer = buffer.duplicate().order(ByteOrder.BIG_ENDIAN);
  }

  public int length()
  {
    return (buffer.getShort(0) & 0xFFFF) + 2;
  }
  
  public int size()
  {
    int n = 0;
    final int len = length();
    for (int i = 2; i < len; )
      {
        int l = buffer.getShort(i+1);
        i += l + 3;
        n++;
      }
    return n;
  }
  
  public ServerName get (int index)
  {
    final int len = length();
    if (len == 0)
      throw new IndexOutOfBoundsException("0; " + index);
    int n = 0;
    int i;
    int l = buffer.getShort(3);
    for (i = 2; i < len && n < index; )
      {
        l = buffer.getShort(i+1);
        i += l + 3;
        n++;
      }
    if (n < index)
      throw new IndexOutOfBoundsException(n + "; " + index);
    ByteBuffer buf = ((ByteBuffer) buffer.duplicate().position(i).limit(i+l+3)).slice();
    return new ServerName (buf);
  }
  
  public void setLength(final int newLength)
  {
    if (newLength < 0 || newLength > 65535)
      throw new IllegalArgumentException("length must be between 0 and 65535");
    buffer.putShort(0, (short) newLength);
  }
  
  public String toString()
  {
    return toString(null);
  }

  public String toString(String prefix)
  {
    StringWriter str = new StringWriter();
    PrintWriter out = new PrintWriter(str);
    if (prefix != null) out.print(prefix);
    out.println ("ServerNameList {");
    String subprefix = "  ";
    if (prefix != null)
      subprefix = prefix + subprefix;
    for (ServerName name : this)
      {
        out.println (name.toString(subprefix));
      }
    if (prefix != null) out.print(prefix);
    out.print ("};");
    return str.toString();
  }
  
  public java.util.Iterator<ServerName> iterator()
  {
    return new Iterator();
  }

  public class Iterator implements java.util.Iterator<ServerName>
  {
    private int index;
    
    public Iterator()
    {
      index = 0;
    }
    
    public boolean hasNext()
    {
      return index < size();
    }
    
    public ServerName next() throws NoSuchElementException
    {
      try
        {
          return get (index++);
        }
      catch (IndexOutOfBoundsException ioobe)
        {
          throw new NoSuchElementException();
        }
    }
    
    public void remove()
    {
      throw new UnsupportedOperationException();
    }
  }

  public static class ServerName implements Constructed
  {
    private final ByteBuffer buffer;
    
    public ServerName(final ByteBuffer buffer)
    {
      this.buffer = buffer.duplicate().order(ByteOrder.BIG_ENDIAN);
    }
    
    public int length()
    {
      return buffer.getShort(1) & 0xFFFF;
    }

    public NameType type()
    {
      int v = (buffer.get(0) & 0xFF);
      if (v == 0)
        {
          return NameType.HOST_NAME;
        }
      throw new IllegalArgumentException ("illegal name type: " + v);
    }
    
    public String name()
    {
      int len = length();
      Charset cs = Charset.forName ("UTF-8");
      return cs.decode(((ByteBuffer) buffer.duplicate().position(3).limit(len))).toString();
    }
    
    public String toString()
    {
      return toString (null);
    }
    
    public String toString(String prefix)
    {
      StringWriter str = new StringWriter();
      PrintWriter out = new PrintWriter(str);
      if (prefix != null) out.print (prefix);
      out.println ("struct {");
      if (prefix != null) out.print (prefix);
      out.print ("  name_type = ");
      out.print (type());
      out.println (";");
      if (prefix != null) out.print (prefix);
      out.print ("  server_name = ");
      out.print (name());
      out.println (";");
      if (prefix != null) out.print (prefix);
      out.print ("} ServerName;");
      return str.toString();
    }
  }

  public static enum NameType
  {
    HOST_NAME (0);
    
    private final int value;
    
    private NameType (int value)
    {
      this.value = value;
    }
    
    public int getValue()
    {
      return value;
    }
  }
}