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-rw-r--r--libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/ec/ECNewPublicKeyTransform.java74
1 files changed, 0 insertions, 74 deletions
diff --git a/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/ec/ECNewPublicKeyTransform.java b/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/ec/ECNewPublicKeyTransform.java
deleted file mode 100644
index d8b1203b5..000000000
--- a/libraries/spongycastle/core/src/main/java/org/spongycastle/crypto/ec/ECNewPublicKeyTransform.java
+++ /dev/null
@@ -1,74 +0,0 @@
-package org.spongycastle.crypto.ec;
-
-import java.math.BigInteger;
-import java.security.SecureRandom;
-
-import org.spongycastle.crypto.CipherParameters;
-import org.spongycastle.crypto.params.ECPublicKeyParameters;
-import org.spongycastle.crypto.params.ParametersWithRandom;
-import org.spongycastle.math.ec.ECPoint;
-
-/**
- * this does your basic Elgamal encryption algorithm using EC
- */
-public class ECNewPublicKeyTransform
- implements ECPairTransform
-{
- private ECPublicKeyParameters key;
- private SecureRandom random;
-
- /**
- * initialise the EC Elgamal engine.
- *
- * @param param the necessary EC key parameters.
- */
- public void init(
- CipherParameters param)
- {
- if (param instanceof ParametersWithRandom)
- {
- ParametersWithRandom p = (ParametersWithRandom)param;
-
- if (!(p.getParameters() instanceof ECPublicKeyParameters))
- {
- throw new IllegalArgumentException("ECPublicKeyParameters are required for new public key transform.");
- }
- this.key = (ECPublicKeyParameters)p.getParameters();
- this.random = p.getRandom();
- }
- else
- {
- if (!(param instanceof ECPublicKeyParameters))
- {
- throw new IllegalArgumentException("ECPublicKeyParameters are required for new public key transform.");
- }
-
- this.key = (ECPublicKeyParameters)param;
- this.random = new SecureRandom();
- }
- }
-
- /**
- * Transform an existing cipher test pair using the ElGamal algorithm. Note: the input cipherText will
- * need to be preserved in order to complete the transformation to the new public key.
- *
- * @param cipherText the EC point to process.
- * @return returns a new ECPair representing the result of the process.
- */
- public ECPair transform(ECPair cipherText)
- {
- if (key == null)
- {
- throw new IllegalStateException("ECNewPublicKeyTransform not initialised");
- }
-
- BigInteger n = key.getParameters().getN();
- BigInteger k = ECUtil.generateK(n, random);
-
- ECPoint g = key.getParameters().getG();
- ECPoint gamma = g.multiply(k);
- ECPoint phi = key.getQ().multiply(k).add(cipherText.getY());
-
- return new ECPair(gamma.normalize(), phi.normalize());
- }
-}