| /* RSAKeyPairX509Codec.java -- X.509 Encoding/Decoding handler |
| Copyright (C) 2006, 2010 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.key.rsa; |
| |
| import gnu.java.security.Configuration; |
| import gnu.java.security.OID; |
| import gnu.java.security.Registry; |
| import gnu.java.security.der.BitString; |
| import gnu.java.security.der.DER; |
| import gnu.java.security.der.DERReader; |
| import gnu.java.security.der.DERValue; |
| import gnu.java.security.der.DERWriter; |
| import gnu.java.security.key.IKeyPairCodec; |
| import gnu.java.security.util.DerUtil; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.math.BigInteger; |
| import java.security.InvalidParameterException; |
| import java.security.PrivateKey; |
| import java.security.PublicKey; |
| import java.util.ArrayList; |
| import java.util.logging.Logger; |
| |
| /** |
| * An implementation of an {@link IKeyPairCodec} that knows how to encode / |
| * decode X.509 ASN.1 external representation of RSA public keys. |
| */ |
| public class RSAKeyPairX509Codec |
| implements IKeyPairCodec |
| { |
| private static final Logger log = Configuration.DEBUG ? |
| Logger.getLogger(RSAKeyPairX509Codec.class.getName()) : null; |
| |
| private static final OID RSA_ALG_OID = new OID(Registry.RSA_OID_STRING); |
| |
| // implicit 0-arguments constructor |
| |
| public int getFormatID() |
| { |
| return X509_FORMAT; |
| } |
| |
| /** |
| * Returns the X.509 ASN.1 <i>SubjectPublicKeyInfo</i> representation of an |
| * RSA public key. The ASN.1 specification, as defined in RFC-3280, and |
| * RFC-2459, is as follows: |
| * |
| * <pre> |
| * SubjectPublicKeyInfo ::= SEQUENCE { |
| * algorithm AlgorithmIdentifier, |
| * subjectPublicKey BIT STRING |
| * } |
| * |
| * AlgorithmIdentifier ::= SEQUENCE { |
| * algorithm OBJECT IDENTIFIER, |
| * parameters ANY DEFINED BY algorithm OPTIONAL |
| * } |
| * </pre> |
| * <p> |
| * As indicated in RFC-2459: "The parameters field shall have ASN.1 type NULL |
| * for this algorithm identifier.". |
| * <p> |
| * The <i>subjectPublicKey</i> field, which is a BIT STRING, contains the |
| * DER-encoded form of the RSA public key defined as: |
| * |
| * <pre> |
| * RSAPublicKey ::= SEQUENCE { |
| * modulus INTEGER, -- n |
| * publicExponent INTEGER -- e |
| * } |
| * </pre> |
| * |
| * @param key the {@link PublicKey} instance to encode. MUST be an instance of |
| * {@link GnuRSAPublicKey}. |
| * @return the ASN.1 representation of the <i>SubjectPublicKeyInfo</i> in an |
| * X.509 certificate. |
| * @throw InvalidParameterException if <code>key</code> is not an instance |
| * of {@link GnuRSAPublicKey} or if an exception occurs during the |
| * marshalling process. |
| */ |
| public byte[] encodePublicKey(PublicKey key) |
| { |
| if (Configuration.DEBUG) |
| log.entering(this.getClass().getName(), "encodePublicKey()", key); |
| if (! (key instanceof GnuRSAPublicKey)) |
| throw new InvalidParameterException("key"); |
| |
| DERValue derOID = new DERValue(DER.OBJECT_IDENTIFIER, RSA_ALG_OID); |
| |
| GnuRSAPublicKey rsaKey = (GnuRSAPublicKey) key; |
| BigInteger n = rsaKey.getN(); |
| BigInteger e = rsaKey.getE(); |
| |
| DERValue derN = new DERValue(DER.INTEGER, n); |
| DERValue derE = new DERValue(DER.INTEGER, e); |
| |
| ArrayList algorithmID = new ArrayList(2); |
| algorithmID.add(derOID); |
| algorithmID.add(new DERValue(DER.NULL, null)); |
| DERValue derAlgorithmID = new DERValue(DER.CONSTRUCTED | DER.SEQUENCE, |
| algorithmID); |
| |
| ArrayList publicKey = new ArrayList(2); |
| publicKey.add(derN); |
| publicKey.add(derE); |
| DERValue derPublicKey = new DERValue(DER.CONSTRUCTED | DER.SEQUENCE, |
| publicKey); |
| byte[] spkBytes = derPublicKey.getEncoded(); |
| DERValue derSPK = new DERValue(DER.BIT_STRING, new BitString(spkBytes)); |
| |
| ArrayList spki = new ArrayList(2); |
| spki.add(derAlgorithmID); |
| spki.add(derSPK); |
| DERValue derSPKI = new DERValue(DER.CONSTRUCTED | DER.SEQUENCE, spki); |
| |
| byte[] result; |
| ByteArrayOutputStream baos = new ByteArrayOutputStream(); |
| try |
| { |
| DERWriter.write(baos, derSPKI); |
| result = baos.toByteArray(); |
| } |
| catch (IOException x) |
| { |
| InvalidParameterException y = new InvalidParameterException(x.getMessage()); |
| y.initCause(x); |
| throw y; |
| } |
| if (Configuration.DEBUG) |
| log.exiting(this.getClass().getName(), "encodePublicKey()", result); |
| return result; |
| } |
| |
| /** |
| * @throws InvalidParameterException ALWAYS. |
| */ |
| public byte[] encodePrivateKey(PrivateKey key) |
| { |
| throw new InvalidParameterException("Wrong format for private keys"); |
| } |
| |
| /** |
| * @param input the byte array to unmarshall into a valid RSA |
| * {@link PublicKey} instance. MUST NOT be null. |
| * @return a new instance of a {@link GnuRSAPublicKey} decoded from the |
| * <i>SubjectPublicKeyInfo</i> material in an X.509 certificate. |
| * @throw InvalidParameterException if an exception occurs during the |
| * unmarshalling process. |
| */ |
| public PublicKey decodePublicKey(byte[] input) |
| { |
| if (Configuration.DEBUG) |
| log.entering(this.getClass().getName(), "decodePublicKey()", input); |
| if (input == null) |
| throw new InvalidParameterException("Input bytes MUST NOT be null"); |
| |
| BigInteger n, e; |
| DERReader der = new DERReader(input); |
| try |
| { |
| DERValue derSPKI = der.read(); |
| DerUtil.checkIsConstructed(derSPKI, "Wrong SubjectPublicKeyInfo field"); |
| |
| DERValue derAlgorithmID = der.read(); |
| DerUtil.checkIsConstructed(derAlgorithmID, "Wrong AlgorithmIdentifier field"); |
| |
| DERValue derOID = der.read(); |
| if (! (derOID.getValue() instanceof OID)) |
| throw new InvalidParameterException("Wrong Algorithm field"); |
| |
| OID algOID = (OID) derOID.getValue(); |
| if (! algOID.equals(RSA_ALG_OID)) |
| throw new InvalidParameterException("Unexpected OID: " + algOID); |
| |
| // rfc-2459 states that this field is OPTIONAL but NULL if/when present |
| DERValue val = der.read(); |
| if (val.getTag() == DER.NULL) |
| val = der.read(); |
| |
| if (! (val.getValue() instanceof BitString)) |
| throw new InvalidParameterException("Wrong SubjectPublicKey field"); |
| |
| byte[] spkBytes = ((BitString) val.getValue()).toByteArray(); |
| |
| der = new DERReader(spkBytes); |
| val = der.read(); |
| DerUtil.checkIsConstructed(derAlgorithmID, "Wrong subjectPublicKey field"); |
| |
| val = der.read(); |
| DerUtil.checkIsBigInteger(val, "Wrong modulus field"); |
| n = (BigInteger) val.getValue(); |
| val = der.read(); |
| DerUtil.checkIsBigInteger(val, "Wrong publicExponent field"); |
| e = (BigInteger) val.getValue(); |
| } |
| catch (IOException x) |
| { |
| InvalidParameterException y = new InvalidParameterException(x.getMessage()); |
| y.initCause(x); |
| throw y; |
| } |
| PublicKey result = new GnuRSAPublicKey(Registry.X509_ENCODING_ID, n, e); |
| if (Configuration.DEBUG) |
| log.exiting(this.getClass().getName(), "decodePublicKey()", result); |
| return result; |
| } |
| |
| /** |
| * @throws InvalidParameterException ALWAYS. |
| */ |
| public PrivateKey decodePrivateKey(byte[] input) |
| { |
| throw new InvalidParameterException("Wrong format for private keys"); |
| } |
| } |