what-the-bank/sources/org/bouncycastle/crypto/agreement/kdf/ConcatenationKDFGenerator.java

93 lines
3.1 KiB
Java

package org.bouncycastle.crypto.agreement.kdf;
import org.bouncycastle.crypto.DataLengthException;
import org.bouncycastle.crypto.DerivationFunction;
import org.bouncycastle.crypto.DerivationParameters;
import org.bouncycastle.crypto.Digest;
import org.bouncycastle.crypto.params.KDFParameters;
/* loaded from: classes6.dex */
public class ConcatenationKDFGenerator implements DerivationFunction {
private Digest digest;
private int hLen;
private byte[] otherInfo;
private byte[] shared;
@Override // org.bouncycastle.crypto.DerivationFunction
public void init(DerivationParameters derivationParameters) {
if (!(derivationParameters instanceof KDFParameters)) {
throw new IllegalArgumentException("KDF parameters required for generator");
}
KDFParameters kDFParameters = (KDFParameters) derivationParameters;
this.shared = kDFParameters.getSharedSecret();
this.otherInfo = kDFParameters.getIV();
}
public Digest getDigest() {
return this.digest;
}
@Override // org.bouncycastle.crypto.DerivationFunction
public int generateBytes(byte[] bArr, int i, int i2) throws DataLengthException, IllegalArgumentException {
int i3;
int i4;
if (bArr.length - i2 < i) {
throw new DataLengthException("output buffer too small");
}
byte[] bArr2 = new byte[this.hLen];
byte[] bArr3 = new byte[4];
this.digest.reset();
int i5 = 1;
if (i2 > this.hLen) {
i3 = 0;
while (true) {
ItoOSP(i5, bArr3);
this.digest.update(bArr3, 0, 4);
Digest digest = this.digest;
byte[] bArr4 = this.shared;
digest.update(bArr4, 0, bArr4.length);
Digest digest2 = this.digest;
byte[] bArr5 = this.otherInfo;
digest2.update(bArr5, 0, bArr5.length);
this.digest.doFinal(bArr2, 0);
System.arraycopy(bArr2, 0, bArr, i + i3, this.hLen);
int i6 = this.hLen;
i3 += i6;
i4 = i5 + 1;
if (i5 >= i2 / i6) {
break;
}
i5 = i4;
}
i5 = i4;
} else {
i3 = 0;
}
if (i3 < i2) {
ItoOSP(i5, bArr3);
this.digest.update(bArr3, 0, 4);
Digest digest3 = this.digest;
byte[] bArr6 = this.shared;
digest3.update(bArr6, 0, bArr6.length);
Digest digest4 = this.digest;
byte[] bArr7 = this.otherInfo;
digest4.update(bArr7, 0, bArr7.length);
this.digest.doFinal(bArr2, 0);
System.arraycopy(bArr2, 0, bArr, i + i3, i2 - i3);
}
return i2;
}
private void ItoOSP(int i, byte[] bArr) {
bArr[0] = (byte) (i >>> 24);
bArr[1] = (byte) (i >>> 16);
bArr[2] = (byte) (i >>> 8);
bArr[3] = (byte) i;
}
public ConcatenationKDFGenerator(Digest digest) {
this.digest = digest;
this.hLen = digest.getDigestSize();
}
}