obex/javax/obex/ObexSession.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (c) 2008-2009, Motorola, Inc.
  *
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * - Redistributions of source code must retain the above copyright notice,
  * this list of conditions and the following disclaimer.
  *
  * - Redistributions in binary form must reproduce the above copyright notice,
  * this list of conditions and the following disclaimer in the documentation
  * and/or other materials provided with the distribution.
  *
  * - Neither the name of the Motorola, Inc. nor the names of its contributors
  * may be used to endorse or promote products derived from this software
  * without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  */

 package javax.obex;

 import java.io.IOException;

 import android.util.Log;

 /**
  * The <code>ObexSession</code> interface characterizes the term
  * "OBEX Connection" as defined in the IrDA Object Exchange Protocol v1.2, which
  * could be the server-side view of an OBEX connection, or the client-side view
  * of the same connection, which is established by server's accepting of a
  * client issued "CONNECT".
  * <P>
  * This interface serves as the common super class for
  * <CODE>ClientSession</CODE> and <CODE>ServerSession</CODE>.
  * @hide
  */
 public class ObexSession {

     private static final String TAG = "ObexSession";
     private static final boolean V = ObexHelper.VDBG;

     protected Authenticator mAuthenticator;

     protected byte[] mChallengeDigest;

     /**
      * Called when the server received an authentication challenge header. This
      * will cause the authenticator to handle the authentication challenge.
      * @param header the header with the authentication challenge
      * @return <code>true</code> if the last request should be resent;
      *         <code>false</code> if the last request should not be resent
      * @throws IOException
      */
     public boolean handleAuthChall(HeaderSet header) throws IOException {
         if (mAuthenticator == null) {
             return false;
         }

         /*
          * An authentication challenge is made up of one required and two
          * optional tag length value triplets. The tag 0x00 is required to be in
          * the authentication challenge and it represents the challenge digest
          * that was received. The tag 0x01 is the options tag. This tag tracks
          * if user ID is required and if full access will be granted. The tag
          * 0x02 is the realm, which provides a description of which user name
          * and password to use.
          */
         byte[] challenge = ObexHelper.getTagValue((byte)0x00, header.mAuthChall);
         byte[] option = ObexHelper.getTagValue((byte)0x01, header.mAuthChall);
         byte[] description = ObexHelper.getTagValue((byte)0x02, header.mAuthChall);

         String realm = null;
         if (description != null) {
             byte[] realmString = new byte[description.length - 1];
             System.arraycopy(description, 1, realmString, 0, realmString.length);

             switch (description[0] & 0xFF) {

                 case ObexHelper.OBEX_AUTH_REALM_CHARSET_ASCII:
                     // ASCII encoding
                     // Fall through
                 case ObexHelper.OBEX_AUTH_REALM_CHARSET_ISO_8859_1:
                     // ISO-8859-1 encoding
                     try {
                         realm = new String(realmString, "ISO8859_1");
                     } catch (Exception e) {
                         throw new IOException("Unsupported Encoding Scheme");
                     }
                     break;

                 case ObexHelper.OBEX_AUTH_REALM_CHARSET_UNICODE:
                     // UNICODE Encoding
                     realm = ObexHelper.convertToUnicode(realmString, false);
                     break;

                 default:
                     throw new IOException("Unsupported Encoding Scheme");
             }
         }

         boolean isUserIDRequired = false;
         boolean isFullAccess = true;
         if (option != null) {
             if ((option[0] & 0x01) != 0) {
                 isUserIDRequired = true;
             }

             if ((option[0] & 0x02) != 0) {
                 isFullAccess = false;
             }
         }

         PasswordAuthentication result = null;
         header.mAuthChall = null;

         try {
             result = mAuthenticator
                     .onAuthenticationChallenge(realm, isUserIDRequired, isFullAccess);
         } catch (Exception e) {
             if (V) Log.d(TAG, "Exception occured - returning false", e);
             return false;
         }

         /*
          * If no password is provided then we not resent the request
          */
         if (result == null) {
             return false;
         }

         byte[] password = result.getPassword();
         if (password == null) {
             return false;
         }

         byte[] userName = result.getUserName();

         /*
          * Create the authentication response header. It includes 1 required and
          * 2 option tag length value triples. The required triple has a tag of
          * 0x00 and is the response digest. The first optional tag is 0x01 and
          * represents the user ID. If no user ID is provided, then no user ID
          * will be sent. The second optional tag is 0x02 and is the challenge
          * that was received. This will always be sent
          */
         if (userName != null) {
             header.mAuthResp = new byte[38 + userName.length];
             header.mAuthResp[36] = (byte)0x01;
             header.mAuthResp[37] = (byte)userName.length;
             System.arraycopy(userName, 0, header.mAuthResp, 38, userName.length);
         } else {
             header.mAuthResp = new byte[36];
         }

         // Create the secret String
         byte[] digest = new byte[challenge.length + password.length + 1];
         System.arraycopy(challenge, 0, digest, 0, challenge.length);
         // Insert colon between challenge and password
         digest[challenge.length] = (byte)0x3A;
         System.arraycopy(password, 0, digest, challenge.length + 1, password.length);

         // Add the Response Digest
         header.mAuthResp[0] = (byte)0x00;
         header.mAuthResp[1] = (byte)0x10;

         System.arraycopy(ObexHelper.computeMd5Hash(digest), 0, header.mAuthResp, 2, 16);

         // Add the challenge
         header.mAuthResp[18] = (byte)0x02;
         header.mAuthResp[19] = (byte)0x10;
         System.arraycopy(challenge, 0, header.mAuthResp, 20, 16);

         return true;
     }

     /**
      * Called when the server received an authentication response header. This
      * will cause the authenticator to handle the authentication response.
      * @param authResp the authentication response
      * @return <code>true</code> if the response passed; <code>false</code> if
      *         the response failed
      */
     public boolean handleAuthResp(byte[] authResp) {
         if (mAuthenticator == null) {
             return false;
         }
         // get the correct password from the application
         byte[] correctPassword = mAuthenticator.onAuthenticationResponse(ObexHelper.getTagValue(
                 (byte)0x01, authResp));
         if (correctPassword == null) {
             return false;
         }

         byte[] temp = new byte[correctPassword.length + 16];

         System.arraycopy(mChallengeDigest, 0, temp, 0, 16);
         System.arraycopy(correctPassword, 0, temp, 16, correctPassword.length);

         byte[] correctResponse = ObexHelper.computeMd5Hash(temp);
         byte[] actualResponse = ObexHelper.getTagValue((byte)0x00, authResp);

         // compare the MD5 hash array .
         for (int i = 0; i < 16; i++) {
             if (correctResponse[i] != actualResponse[i]) {
                 return false;
             }
         }

         return true;
     }
 }
	/*
	* Copyright (c) 2008-2009, Motorola, Inc.
	*
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	*
	* - Redistributions of source code must retain the above copyright notice,
	* this list of conditions and the following disclaimer.
	*
	* - Redistributions in binary form must reproduce the above copyright notice,
	* this list of conditions and the following disclaimer in the documentation
	* and/or other materials provided with the distribution.
	*
	* - Neither the name of the Motorola, Inc. nor the names of its contributors
	* may be used to endorse or promote products derived from this software
	* without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
	* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	* POSSIBILITY OF SUCH DAMAGE.
	*/

	package javax.obex;

	import java.io.IOException;

	import android.util.Log;

	/**
	* The <code>ObexSession</code> interface characterizes the term
	* "OBEX Connection" as defined in the IrDA Object Exchange Protocol v1.2, which
	* could be the server-side view of an OBEX connection, or the client-side view
	* of the same connection, which is established by server's accepting of a
	* client issued "CONNECT".
	* <P>
	* This interface serves as the common super class for
	* <CODE>ClientSession</CODE> and <CODE>ServerSession</CODE>.
	* @hide
	*/
	public class ObexSession {

	private static final String TAG = "ObexSession";
	private static final boolean V = ObexHelper.VDBG;

	protected Authenticator mAuthenticator;

	protected byte[] mChallengeDigest;

	/**
	* Called when the server received an authentication challenge header. This
	* will cause the authenticator to handle the authentication challenge.
	* @param header the header with the authentication challenge
	* @return <code>true</code> if the last request should be resent;
	* <code>false</code> if the last request should not be resent
	* @throws IOException
	*/
	public boolean handleAuthChall(HeaderSet header) throws IOException {
	if (mAuthenticator == null) {
	return false;
	}

	/*
	* An authentication challenge is made up of one required and two
	* optional tag length value triplets. The tag 0x00 is required to be in
	* the authentication challenge and it represents the challenge digest
	* that was received. The tag 0x01 is the options tag. This tag tracks
	* if user ID is required and if full access will be granted. The tag
	* 0x02 is the realm, which provides a description of which user name
	* and password to use.
	*/
	byte[] challenge = ObexHelper.getTagValue((byte)0x00, header.mAuthChall);
	byte[] option = ObexHelper.getTagValue((byte)0x01, header.mAuthChall);
	byte[] description = ObexHelper.getTagValue((byte)0x02, header.mAuthChall);

	String realm = null;
	if (description != null) {
	byte[] realmString = new byte[description.length - 1];
	System.arraycopy(description, 1, realmString, 0, realmString.length);

	switch (description[0] & 0xFF) {

	case ObexHelper.OBEX_AUTH_REALM_CHARSET_ASCII:
	// ASCII encoding
	// Fall through
	case ObexHelper.OBEX_AUTH_REALM_CHARSET_ISO_8859_1:
	// ISO-8859-1 encoding
	try {
	realm = new String(realmString, "ISO8859_1");
	} catch (Exception e) {
	throw new IOException("Unsupported Encoding Scheme");
	}
	break;

	case ObexHelper.OBEX_AUTH_REALM_CHARSET_UNICODE:
	// UNICODE Encoding
	realm = ObexHelper.convertToUnicode(realmString, false);
	break;

	default:
	throw new IOException("Unsupported Encoding Scheme");
	}
	}

	boolean isUserIDRequired = false;
	boolean isFullAccess = true;
	if (option != null) {
	if ((option[0] & 0x01) != 0) {
	isUserIDRequired = true;
	}

	if ((option[0] & 0x02) != 0) {
	isFullAccess = false;
	}
	}

	PasswordAuthentication result = null;
	header.mAuthChall = null;

	try {
	result = mAuthenticator
	.onAuthenticationChallenge(realm, isUserIDRequired, isFullAccess);
	} catch (Exception e) {
	if (V) Log.d(TAG, "Exception occured - returning false", e);
	return false;
	}

	/*
	* If no password is provided then we not resent the request
	*/
	if (result == null) {
	return false;
	}

	byte[] password = result.getPassword();
	if (password == null) {
	return false;
	}

	byte[] userName = result.getUserName();

	/*
	* Create the authentication response header. It includes 1 required and
	* 2 option tag length value triples. The required triple has a tag of
	* 0x00 and is the response digest. The first optional tag is 0x01 and
	* represents the user ID. If no user ID is provided, then no user ID
	* will be sent. The second optional tag is 0x02 and is the challenge
	* that was received. This will always be sent
	*/
	if (userName != null) {
	header.mAuthResp = new byte[38 + userName.length];
	header.mAuthResp[36] = (byte)0x01;
	header.mAuthResp[37] = (byte)userName.length;
	System.arraycopy(userName, 0, header.mAuthResp, 38, userName.length);
	} else {
	header.mAuthResp = new byte[36];
	}

	// Create the secret String
	byte[] digest = new byte[challenge.length + password.length + 1];
	System.arraycopy(challenge, 0, digest, 0, challenge.length);
	// Insert colon between challenge and password
	digest[challenge.length] = (byte)0x3A;
	System.arraycopy(password, 0, digest, challenge.length + 1, password.length);

	// Add the Response Digest
	header.mAuthResp[0] = (byte)0x00;
	header.mAuthResp[1] = (byte)0x10;

	System.arraycopy(ObexHelper.computeMd5Hash(digest), 0, header.mAuthResp, 2, 16);

	// Add the challenge
	header.mAuthResp[18] = (byte)0x02;
	header.mAuthResp[19] = (byte)0x10;
	System.arraycopy(challenge, 0, header.mAuthResp, 20, 16);

	return true;
	}

	/**
	* Called when the server received an authentication response header. This
	* will cause the authenticator to handle the authentication response.
	* @param authResp the authentication response
	* @return <code>true</code> if the response passed; <code>false</code> if
	* the response failed
	*/
	public boolean handleAuthResp(byte[] authResp) {
	if (mAuthenticator == null) {
	return false;
	}
	// get the correct password from the application
	byte[] correctPassword = mAuthenticator.onAuthenticationResponse(ObexHelper.getTagValue(
	(byte)0x01, authResp));
	if (correctPassword == null) {
	return false;
	}

	byte[] temp = new byte[correctPassword.length + 16];

	System.arraycopy(mChallengeDigest, 0, temp, 0, 16);
	System.arraycopy(correctPassword, 0, temp, 16, correctPassword.length);

	byte[] correctResponse = ObexHelper.computeMd5Hash(temp);
	byte[] actualResponse = ObexHelper.getTagValue((byte)0x00, authResp);

	// compare the MD5 hash array .
	for (int i = 0; i < 16; i++) {
	if (correctResponse[i] != actualResponse[i]) {
	return false;
	}
	}

	return true;
	}
	}