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Diffstat (limited to 'libjava/classpath/gnu/java/security/sig/dss')
3 files changed, 632 insertions, 0 deletions
diff --git a/libjava/classpath/gnu/java/security/sig/dss/DSSSignature.java b/libjava/classpath/gnu/java/security/sig/dss/DSSSignature.java new file mode 100644 index 000000000..024521ba4 --- /dev/null +++ b/libjava/classpath/gnu/java/security/sig/dss/DSSSignature.java @@ -0,0 +1,275 @@ +/* DSSSignature.java -- + Copyright (C) 2001, 2002, 2003, 2006 Free Software Foundation, Inc. + +This file is a 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 of the License, 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; if not, write to the Free Software +Foundation, Inc., 51 Franklin St, 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.dss; + +import gnu.java.security.Registry; +import gnu.java.security.hash.IMessageDigest; +import gnu.java.security.hash.Sha160; +import gnu.java.security.prng.IRandom; +import gnu.java.security.sig.BaseSignature; +import gnu.java.security.sig.ISignature; + +import java.math.BigInteger; +import java.security.PrivateKey; +import java.security.PublicKey; +import java.security.interfaces.DSAPrivateKey; +import java.security.interfaces.DSAPublicKey; +import java.util.HashMap; +import java.util.Map; +import java.util.Random; + +/** + * The DSS (Digital Signature Standard) algorithm makes use of the following + * parameters: + * <ol> + * <li>p: A prime modulus, where + * <code>2<sup>L-1</sup> < p < 2<sup>L</sup> </code> for <code>512 <= L + * <= 1024</code> and <code>L</code> a multiple of <code>64</code>.</li> + * <li>q: A prime divisor of <code>p - 1</code>, where <code>2<sup>159</sup> + * < q < 2<sup>160</sup></code>.</li> + * <li>g: Where <code>g = h<sup>(p-1)</sup>/q mod p</code>, where + * <code>h</code> is any integer with <code>1 < h < p - 1</code> such + * that <code>h<sup> (p-1)</sup>/q mod p > 1</code> (<code>g</code> has order + * <code>q mod p</code>).</li> + * <li>x: A randomly or pseudorandomly generated integer with <code>0 < x + * < q</code>.</li> + * <li>y: <code>y = g<sup>x</sup> mod p</code>.</li> + * <li>k: A randomly or pseudorandomly generated integer with <code>0 < k + * < q</code>.</li> + * </ol> + * <p> + * The integers <code>p</code>, <code>q</code>, and <code>g</code> can be + * public and can be common to a group of users. A user's private and public + * keys are <code>x</code> and <code>y</code>, respectively. They are + * normally fixed for a period of time. Parameters <code>x</code> and + * <code>k</code> are used for signature generation only, and must be kept + * secret. Parameter <code>k</code> must be regenerated for each signature. + * <p> + * The signature of a message <code>M</code> is the pair of numbers + * <code>r</code> and <code>s</code> computed according to the equations below: + * <ul> + * <li><code>r = (g<sup>k</sup> mod p) mod q</code> and</li> + * <li><code>s = (k<sup>-1</sup>(SHA(M) + xr)) mod q</code>.</li> + * </ul> + * <p> + * In the above, <code>k<sup>-1</sup></code> is the multiplicative inverse of + * <code>k</code>, <code>mod q</code>; i.e., <code>(k<sup>-1</sup> k) mod q = + * 1</code> and <code>0 < k-1 < q</code>. The value of <code>SHA(M)</code> + * is a 160-bit string output by the Secure Hash Algorithm specified in FIPS + * 180. For use in computing <code>s</code>, this string must be converted to + * an integer. + * <p> + * As an option, one may wish to check if <code>r == 0</code> or <code>s == 0 + * </code>. + * If either <code>r == 0</code> or <code>s == 0</code>, a new value of + * <code>k</code> should be generated and the signature should be recalculated + * (it is extremely unlikely that <code>r == 0</code> or <code>s == 0</code> if + * signatures are generated properly). + * <p> + * The signature is transmitted along with the message to the verifier. + * <p> + * References: + * <ol> + * <li><a href="http://www.itl.nist.gov/fipspubs/fip186.htm">Digital Signature + * Standard (DSS)</a>, Federal Information Processing Standards Publication + * 186. National Institute of Standards and Technology.</li> + * </ol> + */ +public class DSSSignature + extends BaseSignature +{ + /** Trivial 0-arguments constructor. */ + public DSSSignature() + { + super(Registry.DSS_SIG, new Sha160()); + } + + /** Private constructor for cloning purposes. */ + private DSSSignature(DSSSignature that) + { + this(); + + this.publicKey = that.publicKey; + this.privateKey = that.privateKey; + this.md = (IMessageDigest) that.md.clone(); + } + + public static final BigInteger[] sign(final DSAPrivateKey k, final byte[] h) + { + final DSSSignature sig = new DSSSignature(); + final Map attributes = new HashMap(); + attributes.put(ISignature.SIGNER_KEY, k); + sig.setupSign(attributes); + return sig.computeRS(h); + } + + public static final BigInteger[] sign(final DSAPrivateKey k, final byte[] h, + Random rnd) + { + final DSSSignature sig = new DSSSignature(); + final Map attributes = new HashMap(); + attributes.put(ISignature.SIGNER_KEY, k); + if (rnd != null) + attributes.put(ISignature.SOURCE_OF_RANDOMNESS, rnd); + + sig.setupSign(attributes); + return sig.computeRS(h); + } + + public static final BigInteger[] sign(final DSAPrivateKey k, final byte[] h, + IRandom irnd) + { + final DSSSignature sig = new DSSSignature(); + final Map attributes = new HashMap(); + attributes.put(ISignature.SIGNER_KEY, k); + if (irnd != null) + attributes.put(ISignature.SOURCE_OF_RANDOMNESS, irnd); + + sig.setupSign(attributes); + return sig.computeRS(h); + } + + public static final boolean verify(final DSAPublicKey k, final byte[] h, + final BigInteger[] rs) + { + final DSSSignature sig = new DSSSignature(); + final Map attributes = new HashMap(); + attributes.put(ISignature.VERIFIER_KEY, k); + sig.setupVerify(attributes); + return sig.checkRS(rs, h); + } + + public Object clone() + { + return new DSSSignature(this); + } + + protected void setupForVerification(PublicKey k) + throws IllegalArgumentException + { + if (! (k instanceof DSAPublicKey)) + throw new IllegalArgumentException(); + + this.publicKey = k; + } + + protected void setupForSigning(PrivateKey k) throws IllegalArgumentException + { + if (! (k instanceof DSAPrivateKey)) + throw new IllegalArgumentException(); + + this.privateKey = k; + } + + protected Object generateSignature() throws IllegalStateException + { + final BigInteger[] rs = computeRS(md.digest()); + return encodeSignature(rs[0], rs[1]); + } + + protected boolean verifySignature(Object sig) throws IllegalStateException + { + final BigInteger[] rs = decodeSignature(sig); + return checkRS(rs, md.digest()); + } + + /** + * Returns the output of a signature generation phase. + * + * @return an object encapsulating the DSS signature pair <code>r</code> and + * <code>s</code>. + */ + private Object encodeSignature(BigInteger r, BigInteger s) + { + return new BigInteger[] { r, s }; + } + + /** + * Returns the output of a previously generated signature object as a pair of + * {@link java.math.BigInteger}. + * + * @return the DSS signature pair <code>r</code> and <code>s</code>. + */ + private BigInteger[] decodeSignature(Object signature) + { + return (BigInteger[]) signature; + } + + private BigInteger[] computeRS(final byte[] digestBytes) + { + final BigInteger p = ((DSAPrivateKey) privateKey).getParams().getP(); + final BigInteger q = ((DSAPrivateKey) privateKey).getParams().getQ(); + final BigInteger g = ((DSAPrivateKey) privateKey).getParams().getG(); + final BigInteger x = ((DSAPrivateKey) privateKey).getX(); + final BigInteger m = new BigInteger(1, digestBytes); + BigInteger k, r, s; + final byte[] kb = new byte[20]; // we'll use 159 bits only + while (true) + { + this.nextRandomBytes(kb); + k = new BigInteger(1, kb); + k.clearBit(159); + r = g.modPow(k, p).mod(q); + if (r.equals(BigInteger.ZERO)) + continue; + + s = m.add(x.multiply(r)).multiply(k.modInverse(q)).mod(q); + if (s.equals(BigInteger.ZERO)) + continue; + + break; + } + return new BigInteger[] { r, s }; + } + + private boolean checkRS(final BigInteger[] rs, final byte[] digestBytes) + { + final BigInteger r = rs[0]; + final BigInteger s = rs[1]; + final BigInteger g = ((DSAPublicKey) publicKey).getParams().getG(); + final BigInteger p = ((DSAPublicKey) publicKey).getParams().getP(); + final BigInteger q = ((DSAPublicKey) publicKey).getParams().getQ(); + final BigInteger y = ((DSAPublicKey) publicKey).getY(); + final BigInteger w = s.modInverse(q); + final BigInteger u1 = w.multiply(new BigInteger(1, digestBytes)).mod(q); + final BigInteger u2 = r.multiply(w).mod(q); + final BigInteger v = g.modPow(u1, p).multiply(y.modPow(u2, p)).mod(p).mod(q); + return v.equals(r); + } +} diff --git a/libjava/classpath/gnu/java/security/sig/dss/DSSSignatureRawCodec.java b/libjava/classpath/gnu/java/security/sig/dss/DSSSignatureRawCodec.java new file mode 100644 index 000000000..169f84bd1 --- /dev/null +++ b/libjava/classpath/gnu/java/security/sig/dss/DSSSignatureRawCodec.java @@ -0,0 +1,164 @@ +/* DSSSignatureRawCodec.java -- + Copyright (C) 2001, 2002, 2003, 2006 Free Software Foundation, Inc. + +This file is a 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 of the License, 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; if not, write to the Free Software +Foundation, Inc., 51 Franklin St, 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.dss; + +import gnu.java.security.Registry; +import gnu.java.security.sig.ISignatureCodec; + +import java.io.ByteArrayOutputStream; +import java.math.BigInteger; + +/** + * An object that implements the {@link ISignatureCodec} operations for the + * <i>Raw</i> format to use with DSS signatures. + */ +public class DSSSignatureRawCodec + implements ISignatureCodec +{ + public int getFormatID() + { + return RAW_FORMAT; + } + + /** + * Returns the encoded form of the designated DSS (Digital Signature Standard) + * signature object according to the <i>Raw</i> format supported by this + * library. + * <p> + * The <i>Raw</i> format for a DSA signature, in this implementation, is a + * byte sequence consisting of the following: + * <ol> + * <li>4-byte magic consisting of the value of the literal + * {@link Registry#MAGIC_RAW_DSS_SIGNATURE},</li> + * <li>1-byte version consisting of the constant: 0x01,</li> + * <li>4-byte count of following bytes representing the DSS parameter + * <code>r</code> in internet order,</li> + * <li>n-bytes representation of a {@link BigInteger} obtained by invoking + * the <code>toByteArray()</code> method on the DSS parameter <code>r</code>, + * </li> + * <li>4-byte count of following bytes representing the DSS parameter + * <code>s</code>,</li> + * <li>n-bytes representation of a {@link BigInteger} obtained by invoking + * the <code>toByteArray()</code> method on the DSS parameter <code>s</code>. + * </li> + * </ol> + * + * @param signature the signature to encode, consisting of the two DSS + * parameters <code>r</code> and <code>s</code> as a + * {@link BigInteger} array. + * @return the <i>Raw</i> format encoding of the designated signature. + * @exception IllegalArgumentException if the designated signature is not a + * DSS (Digital Signature Standard) one. + */ + public byte[] encodeSignature(Object signature) + { + BigInteger r, s; + try + { + BigInteger[] sig = (BigInteger[]) signature; + r = sig[0]; + s = sig[1]; + } + catch (Exception x) + { + throw new IllegalArgumentException("signature"); + } + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + // magic + baos.write(Registry.MAGIC_RAW_DSS_SIGNATURE[0]); + baos.write(Registry.MAGIC_RAW_DSS_SIGNATURE[1]); + baos.write(Registry.MAGIC_RAW_DSS_SIGNATURE[2]); + baos.write(Registry.MAGIC_RAW_DSS_SIGNATURE[3]); + // version + baos.write(0x01); + // r + byte[] buffer = r.toByteArray(); + 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); + // s + buffer = s.toByteArray(); + 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(); + } + + public Object decodeSignature(byte[] k) + { + // magic + if (k[0] != Registry.MAGIC_RAW_DSS_SIGNATURE[0] + || k[1] != Registry.MAGIC_RAW_DSS_SIGNATURE[1] + || k[2] != Registry.MAGIC_RAW_DSS_SIGNATURE[2] + || k[3] != Registry.MAGIC_RAW_DSS_SIGNATURE[3]) + throw new IllegalArgumentException("magic"); + // version + if (k[4] != 0x01) + throw new IllegalArgumentException("version"); + + int i = 5; + int l; + byte[] buffer; + // r + l = k[i++] << 24 + | (k[i++] & 0xFF) << 16 + | (k[i++] & 0xFF) << 8 + | (k[i++] & 0xFF); + buffer = new byte[l]; + System.arraycopy(k, i, buffer, 0, l); + i += l; + BigInteger r = new BigInteger(1, buffer); + // s + l = k[i++] << 24 + | (k[i++] & 0xFF) << 16 + | (k[i++] & 0xFF) << 8 + | (k[i++] & 0xFF); + buffer = new byte[l]; + System.arraycopy(k, i, buffer, 0, l); + i += l; + BigInteger s = new BigInteger(1, buffer); + return new BigInteger[] { r, s }; + } +} diff --git a/libjava/classpath/gnu/java/security/sig/dss/DSSSignatureX509Codec.java b/libjava/classpath/gnu/java/security/sig/dss/DSSSignatureX509Codec.java new file mode 100644 index 000000000..d0a0188fb --- /dev/null +++ b/libjava/classpath/gnu/java/security/sig/dss/DSSSignatureX509Codec.java @@ -0,0 +1,193 @@ +/* DSSSignatureX509Codec.java -- X.509 encoder/decoder for DSS signatures + 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.dss; + +import gnu.java.security.Registry; +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.sig.ISignatureCodec; +import gnu.java.security.util.DerUtil; + +import java.io.ByteArrayOutputStream; +import java.io.IOException; +import java.math.BigInteger; +import java.security.InvalidParameterException; +import java.util.ArrayList; + +/** + * An implementation of an {@link ISignatureCodec} that knows to encode and + * decode DSS signatures into the raw bytes which would constitute a DER-encoded + * form of the ASN.1 structure defined in RFC-2459, and RFC-2313 as described in + * the next paragraphs. + * <p> + * Digital signatures when transmitted in an X.509 certificates are encoded + * in DER (Distinguished Encoding Rules) as a BIT STRING; i.e. + * + * <pre> + * Certificate ::= SEQUENCE { + * tbsCertificate TBSCertificate, + * signatureAlgorithm AlgorithmIdentifier, + * signature BIT STRING + * } + * </pre> + * <p> + * The output of the encoder, and the input of the decoder, of this codec are + * then the <i>raw</i> bytes of such a BIT STRING; i.e. not the DER-encoded + * form itself. + * <p> + * RFC-2459 states that, for the Digital Signature Standard (DSS), which + * generates two MPIs, commonly called <code>r</code> and <code>s</code>, as the + * result of digitally signing a message, these two numbers will be transferred + * as the following ASN.1 structure: + * + * <pre> + * Dss-Sig-Value ::= SEQUENCE { + * r INTEGER, + * s INTEGER + * } + * </pre> + * <p> + * Client code that needs to build a DER BIT STRING <b>MUST</b> construct such + * an ASN.1 value. The following is an example of how to do this: + * <p> + * <pre> + * ... + * import gnu.java.security.der.BitString; + * import gnu.java.security.der.DER; + * import gnu.java.security.der.DERValue; + * ... + * DERValue bitString = new DERValue(DER.BIT_STRING, new BitString(sigBytes)); + * ... + * </pre> + */ +public class DSSSignatureX509Codec + implements ISignatureCodec +{ + // implicit 0-arguments constructor + + public int getFormatID() + { + return Registry.X509_ENCODING_ID; + } + + /** + * Encodes a DSS Signature output as the <i>signature</i> raw bytes which can + * be used to construct an ASN.1 DER-encoded BIT STRING as defined in the + * documentation of this class. + * + * @param signature the output of the DSS signature algorithm; i.e. the value + * returned by the invocation of + * {@link gnu.java.security.sig.ISignature#sign()} method. In the + * case of a DSS signature this is an array of two MPIs called + * <code>r</code> and <code>s</code>. + * @return the raw bytes of a DSS signature which could be then used as the + * contents of a BIT STRING as per rfc-2459. + * @throws InvalidParameterException if an exception occurs during the + * marshalling process. + */ + public byte[] encodeSignature(Object signature) + { + BigInteger[] rs = (BigInteger[]) signature; + + DERValue derR = new DERValue(DER.INTEGER, rs[0]); + DERValue derS = new DERValue(DER.INTEGER, rs[1]); + + ArrayList dssSigValue = new ArrayList(2); + dssSigValue.add(derR); + dssSigValue.add(derS); + DERValue derDssSigValue = new DERValue(DER.CONSTRUCTED | DER.SEQUENCE, + dssSigValue); + byte[] result; + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + try + { + DERWriter.write(baos, derDssSigValue); + result = baos.toByteArray(); + } + catch (IOException x) + { + InvalidParameterException y = new InvalidParameterException(); + y.initCause(x); + throw y; + } + + return result; + } + + /** + * Decodes a <i>signature</i> as defined in the documentation of this class. + * + * @param input the byte array to unmarshall into a valid DSS signature + * instance; i.e. an array of two MPIs. MUST NOT be null. + * @return an array of two MPIs, <code>r</code> and <code>s</code> in this + * order, decoded from the designated <code>input</code>. + * @throw InvalidParameterException if an exception occurs during the + * unmarshalling process. + */ + public Object decodeSignature(byte[] input) + { + if (input == null) + throw new InvalidParameterException("Input bytes MUST NOT be null"); + + BigInteger r, s; + DERReader der = new DERReader(input); + try + { + DERValue derDssSigValue = der.read(); + DerUtil.checkIsConstructed(derDssSigValue, "Wrong Dss-Sig-Value field"); + + DERValue val = der.read(); + DerUtil.checkIsBigInteger(val, "Wrong R field"); + r = (BigInteger) val.getValue(); + val = der.read(); + DerUtil.checkIsBigInteger(val, "Wrong S field"); + s = (BigInteger) val.getValue(); + } + catch (IOException x) + { + InvalidParameterException y = new InvalidParameterException(); + y.initCause(x); + throw y; + } + + return new BigInteger[] { r, s }; + } +} |