what-the-bank/sources/org/bouncycastle/crypto/signers/ECGOST3410Signer.java

93 lines
4.1 KiB
Java

package org.bouncycastle.crypto.signers;
import java.math.BigInteger;
import java.security.SecureRandom;
import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.DSA;
import org.bouncycastle.crypto.params.ECDomainParameters;
import org.bouncycastle.crypto.params.ECKeyParameters;
import org.bouncycastle.crypto.params.ECPrivateKeyParameters;
import org.bouncycastle.crypto.params.ECPublicKeyParameters;
import org.bouncycastle.crypto.params.ParametersWithRandom;
import org.bouncycastle.math.ec.ECAlgorithms;
import org.bouncycastle.math.ec.ECConstants;
import org.bouncycastle.math.ec.ECMultiplier;
import org.bouncycastle.math.ec.ECPoint;
import org.bouncycastle.math.ec.FixedPointCombMultiplier;
/* loaded from: classes6.dex */
public class ECGOST3410Signer implements DSA {
ECKeyParameters key;
SecureRandom random;
@Override // org.bouncycastle.crypto.DSA
public boolean verifySignature(byte[] bArr, BigInteger bigInteger, BigInteger bigInteger2) {
int length = bArr.length;
byte[] bArr2 = new byte[length];
for (int i = 0; i != length; i++) {
bArr2[i] = bArr[(length - 1) - i];
}
BigInteger bigInteger3 = new BigInteger(1, bArr2);
BigInteger n = this.key.getParameters().getN();
if (bigInteger.compareTo(ECConstants.ONE) < 0 || bigInteger.compareTo(n) >= 0 || bigInteger2.compareTo(ECConstants.ONE) < 0 || bigInteger2.compareTo(n) >= 0) {
return false;
}
BigInteger modInverse = bigInteger3.modInverse(n);
ECPoint normalize = ECAlgorithms.sumOfTwoMultiplies(this.key.getParameters().getG(), bigInteger2.multiply(modInverse).mod(n), ((ECPublicKeyParameters) this.key).getQ(), n.subtract(bigInteger).multiply(modInverse).mod(n)).normalize();
if (normalize.isInfinity()) {
return false;
}
return normalize.getAffineXCoord().toBigInteger().mod(n).equals(bigInteger);
}
@Override // org.bouncycastle.crypto.DSA
public void init(boolean z, CipherParameters cipherParameters) {
ECKeyParameters eCKeyParameters;
if (!z) {
eCKeyParameters = (ECPublicKeyParameters) cipherParameters;
} else {
if (cipherParameters instanceof ParametersWithRandom) {
ParametersWithRandom parametersWithRandom = (ParametersWithRandom) cipherParameters;
this.random = parametersWithRandom.getRandom();
this.key = (ECPrivateKeyParameters) parametersWithRandom.getParameters();
return;
}
this.random = new SecureRandom();
eCKeyParameters = (ECPrivateKeyParameters) cipherParameters;
}
this.key = eCKeyParameters;
}
@Override // org.bouncycastle.crypto.DSA
public BigInteger[] generateSignature(byte[] bArr) {
int length = bArr.length;
byte[] bArr2 = new byte[length];
for (int i = 0; i != length; i++) {
bArr2[i] = bArr[(length - 1) - i];
}
BigInteger bigInteger = new BigInteger(1, bArr2);
ECDomainParameters parameters = this.key.getParameters();
BigInteger n = parameters.getN();
BigInteger d = ((ECPrivateKeyParameters) this.key).getD();
ECMultiplier createBasePointMultiplier = createBasePointMultiplier();
while (true) {
BigInteger bigInteger2 = new BigInteger(n.bitLength(), this.random);
if (!bigInteger2.equals(ECConstants.ZERO)) {
BigInteger mod = createBasePointMultiplier.multiply(parameters.getG(), bigInteger2).normalize().getAffineXCoord().toBigInteger().mod(n);
if (mod.equals(ECConstants.ZERO)) {
continue;
} else {
BigInteger mod2 = bigInteger2.multiply(bigInteger).add(d.multiply(mod)).mod(n);
if (!mod2.equals(ECConstants.ZERO)) {
return new BigInteger[]{mod, mod2};
}
}
}
}
}
protected ECMultiplier createBasePointMultiplier() {
return new FixedPointCombMultiplier();
}
}