diff options
Diffstat (limited to 'libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dh/KeyAgreementSpi.java')
-rw-r--r-- | libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dh/KeyAgreementSpi.java | 227 |
1 files changed, 0 insertions, 227 deletions
diff --git a/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dh/KeyAgreementSpi.java b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dh/KeyAgreementSpi.java deleted file mode 100644 index 631272363..000000000 --- a/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dh/KeyAgreementSpi.java +++ /dev/null @@ -1,227 +0,0 @@ -package org.spongycastle.jcajce.provider.asymmetric.dh; - -import java.math.BigInteger; -import java.security.InvalidAlgorithmParameterException; -import java.security.InvalidKeyException; -import java.security.Key; -import java.security.SecureRandom; -import java.security.spec.AlgorithmParameterSpec; -import java.util.Hashtable; - -import javax.crypto.SecretKey; -import javax.crypto.ShortBufferException; -import javax.crypto.interfaces.DHPrivateKey; -import javax.crypto.interfaces.DHPublicKey; -import javax.crypto.spec.DHParameterSpec; -import javax.crypto.spec.SecretKeySpec; - -import org.spongycastle.crypto.params.DESParameters; -import org.spongycastle.util.Integers; -import org.spongycastle.util.Strings; - -/** - * Diffie-Hellman key agreement. There's actually a better way of doing this - * if you are using long term public keys, see the light-weight version for - * details. - */ -public class KeyAgreementSpi - extends javax.crypto.KeyAgreementSpi -{ - private BigInteger x; - private BigInteger p; - private BigInteger g; - private BigInteger result; - - private static final Hashtable algorithms = new Hashtable(); - - static - { - Integer i64 = Integers.valueOf(64); - Integer i192 = Integers.valueOf(192); - Integer i128 = Integers.valueOf(128); - Integer i256 = Integers.valueOf(256); - - algorithms.put("DES", i64); - algorithms.put("DESEDE", i192); - algorithms.put("BLOWFISH", i128); - algorithms.put("AES", i256); - } - - private byte[] bigIntToBytes( - BigInteger r) - { - // - // RFC 2631 (2.1.2) specifies that the secret should be padded with leading zeros if necessary - // must be the same length as p - // - int expectedLength = (p.bitLength() + 7) / 8; - - byte[] tmp = r.toByteArray(); - - if (tmp.length == expectedLength) - { - return tmp; - } - - if (tmp[0] == 0 && tmp.length == expectedLength + 1) - { - byte[] rv = new byte[tmp.length - 1]; - - System.arraycopy(tmp, 1, rv, 0, rv.length); - return rv; - } - - // tmp must be shorter than expectedLength - // pad to the left with zeros. - byte[] rv = new byte[expectedLength]; - - System.arraycopy(tmp, 0, rv, rv.length - tmp.length, tmp.length); - - return rv; - } - - protected Key engineDoPhase( - Key key, - boolean lastPhase) - throws InvalidKeyException, IllegalStateException - { - if (x == null) - { - throw new IllegalStateException("Diffie-Hellman not initialised."); - } - - if (!(key instanceof DHPublicKey)) - { - throw new InvalidKeyException("DHKeyAgreement doPhase requires DHPublicKey"); - } - DHPublicKey pubKey = (DHPublicKey)key; - - if (!pubKey.getParams().getG().equals(g) || !pubKey.getParams().getP().equals(p)) - { - throw new InvalidKeyException("DHPublicKey not for this KeyAgreement!"); - } - - if (lastPhase) - { - result = ((DHPublicKey)key).getY().modPow(x, p); - return null; - } - else - { - result = ((DHPublicKey)key).getY().modPow(x, p); - } - - return new BCDHPublicKey(result, pubKey.getParams()); - } - - protected byte[] engineGenerateSecret() - throws IllegalStateException - { - if (x == null) - { - throw new IllegalStateException("Diffie-Hellman not initialised."); - } - - return bigIntToBytes(result); - } - - protected int engineGenerateSecret( - byte[] sharedSecret, - int offset) - throws IllegalStateException, ShortBufferException - { - if (x == null) - { - throw new IllegalStateException("Diffie-Hellman not initialised."); - } - - byte[] secret = bigIntToBytes(result); - - if (sharedSecret.length - offset < secret.length) - { - throw new ShortBufferException("DHKeyAgreement - buffer too short"); - } - - System.arraycopy(secret, 0, sharedSecret, offset, secret.length); - - return secret.length; - } - - protected SecretKey engineGenerateSecret( - String algorithm) - { - if (x == null) - { - throw new IllegalStateException("Diffie-Hellman not initialised."); - } - - String algKey = Strings.toUpperCase(algorithm); - byte[] res = bigIntToBytes(result); - - if (algorithms.containsKey(algKey)) - { - Integer length = (Integer)algorithms.get(algKey); - - byte[] key = new byte[length.intValue() / 8]; - System.arraycopy(res, 0, key, 0, key.length); - - if (algKey.startsWith("DES")) - { - DESParameters.setOddParity(key); - } - - return new SecretKeySpec(key, algorithm); - } - - return new SecretKeySpec(res, algorithm); - } - - protected void engineInit( - Key key, - AlgorithmParameterSpec params, - SecureRandom random) - throws InvalidKeyException, InvalidAlgorithmParameterException - { - if (!(key instanceof DHPrivateKey)) - { - throw new InvalidKeyException("DHKeyAgreement requires DHPrivateKey for initialisation"); - } - DHPrivateKey privKey = (DHPrivateKey)key; - - if (params != null) - { - if (!(params instanceof DHParameterSpec)) - { - throw new InvalidAlgorithmParameterException("DHKeyAgreement only accepts DHParameterSpec"); - } - DHParameterSpec p = (DHParameterSpec)params; - - this.p = p.getP(); - this.g = p.getG(); - } - else - { - this.p = privKey.getParams().getP(); - this.g = privKey.getParams().getG(); - } - - this.x = this.result = privKey.getX(); - } - - protected void engineInit( - Key key, - SecureRandom random) - throws InvalidKeyException - { - if (!(key instanceof DHPrivateKey)) - { - throw new InvalidKeyException("DHKeyAgreement requires DHPrivateKey"); - } - - DHPrivateKey privKey = (DHPrivateKey)key; - - this.p = privKey.getParams().getP(); - this.g = privKey.getParams().getG(); - this.x = this.result = privKey.getX(); - } -} |