| /* RSAPKCS1V1_5SignatureRawCodec.java -- Raw RSA PKCS1 v1.5 signature codeec |
| Copyright (C) 2006 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.java.security.sig.rsa; |
| |
| import java.io.ByteArrayOutputStream; |
| |
| import gnu.java.security.Registry; |
| import gnu.java.security.sig.ISignatureCodec; |
| |
| /** |
| * An object that implements the {@link ISignatureCodec} operations for the |
| * <i>Raw</i> format to use with RSA-PKCS#1 v1.5 signatures. |
| */ |
| public class RSAPKCS1V1_5SignatureRawCodec |
| implements ISignatureCodec |
| { |
| public int getFormatID() |
| { |
| return RAW_FORMAT; |
| } |
| |
| /** |
| * Returns the encoded form of the designated RSA-PKCS#1 (v1.5) signature |
| * object according to the <i>Raw</i> format supported by this library. |
| * <p> |
| * The <i>Raw</i> format for such a signature, in this implementation, is a |
| * byte sequence consisting of the following: |
| * <p> |
| * <ol> |
| * <li>4-byte magic consisting of the value of the literal |
| * {@link Registry#MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE}, |
| * <li> |
| * <li>1-byte version consisting of the constant: 0x01,</li> |
| * <li>4-byte count of following bytes representing the RSA-PKCS#1 (v1.5) |
| * signature bytes in internet order,</li> |
| * <li>the RSA-PKCS#1 (v1.5) signature bytes in internet order.</li> |
| * </ol> |
| * |
| * @param signature the signature to encode, consisting of the output of the |
| * <code>sign()</code> method of a {@link RSAPKCS1V1_5Signature} |
| * instance --a byte array. |
| * @return the <i>Raw</i> format encoding of the designated signature. |
| * @exception IllegalArgumentException if the designated signature is not an |
| * RSA-PKCS#1 (v1.5) one. |
| */ |
| public byte[] encodeSignature(Object signature) |
| { |
| byte[] buffer; |
| try |
| { |
| buffer = (byte[]) signature; |
| } |
| catch (Exception x) |
| { |
| throw new IllegalArgumentException("Signature/codec mismatch"); |
| } |
| |
| ByteArrayOutputStream baos = new ByteArrayOutputStream(); |
| |
| // magic |
| baos.write(Registry.MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE[0]); |
| baos.write(Registry.MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE[1]); |
| baos.write(Registry.MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE[2]); |
| baos.write(Registry.MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE[3]); |
| |
| // version |
| baos.write(0x01); |
| |
| // signature bytes |
| int length = buffer.length; |
| baos.write( length >>> 24); |
| baos.write((length >>> 16) & 0xFF); |
| baos.write((length >>> 8) & 0xFF); |
| baos.write( length & 0xFF); |
| baos.write(buffer, 0, length); |
| |
| return baos.toByteArray(); |
| } |
| |
| /** |
| * Returns the decoded object from a designated input assumed to have been |
| * generated by the {@link #encodeSignature(Object)} method. |
| * |
| * @param input the input bytes of a previously Raw-encoded RSA PKCS1 (v1.5) |
| * signature. |
| * @return the signature object. |
| * @throws IllegalArgumentException if the designated input does not start |
| * with the right <i>magic</i> characters, or if the <i>version</i> |
| * is not supported. |
| */ |
| public Object decodeSignature(byte[] input) |
| { |
| // magic |
| if (input[0] != Registry.MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE[0] |
| || input[1] != Registry.MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE[1] |
| || input[2] != Registry.MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE[2] |
| || input[3] != Registry.MAGIC_RAW_RSA_PKCS1V1_5_SIGNATURE[3]) |
| throw new IllegalArgumentException("Signature/codec mismatch"); |
| |
| // version |
| if (input[4] != 0x01) |
| throw new IllegalArgumentException("Wrong or unsupported format version"); |
| |
| int i = 5; |
| int l; |
| |
| // signature bytes |
| l = input[i++] << 24 |
| | (input[i++] & 0xFF) << 16 |
| | (input[i++] & 0xFF) << 8 |
| | (input[i++] & 0xFF); |
| byte[] result = new byte[l]; |
| System.arraycopy(input, i, result, 0, l); |
| |
| return result; |
| } |
| } |