Example usage for org.bouncycastle.asn1.x9 X9IntegerConverter X9IntegerConverter

Introduction

In this page you can find the example usage for org.bouncycastle.asn1.x9 X9IntegerConverter X9IntegerConverter.

Prototype

X9IntegerConverter

Source Link

Usage

From source file:at.asitplus.regkassen.common.util.CryptoUtil.java

License:Apache License

/**
 * Helper method to convert DER-encoded signature values (e.g. used by Java)
 * to concatenated signature values//  w  w  w .  j a v a 2 s . co  m
 * (as used by the JWS-standard)
 *
 * @param derEncodedSignatureValue
 *          DER-encoded signature value
 * @return concatenated signature value (as used by JWS standard)
 * @throws IOException
 */
public static byte[] convertDEREncodedSignatureToJWSConcatenated(final byte[] derEncodedSignatureValue)
        throws IOException {
    final ASN1InputStream asn1InputStream = new ASN1InputStream(derEncodedSignatureValue);
    final ASN1Primitive asn1Primitive = asn1InputStream.readObject();
    asn1InputStream.close();
    final ASN1Sequence asn1Sequence = (ASN1Sequence.getInstance(asn1Primitive));
    final ASN1Integer rASN1 = (ASN1Integer) asn1Sequence.getObjectAt(0);
    final ASN1Integer sASN1 = (ASN1Integer) asn1Sequence.getObjectAt(1);
    final X9IntegerConverter x9IntegerConverter = new X9IntegerConverter();
    final byte[] r = x9IntegerConverter.integerToBytes(rASN1.getValue(), 32);
    final byte[] s = x9IntegerConverter.integerToBytes(sASN1.getValue(), 32);

    final byte[] concatenatedSignatureValue = new byte[64];
    System.arraycopy(r, 0, concatenatedSignatureValue, 0, 32);
    System.arraycopy(s, 0, concatenatedSignatureValue, 32, 32);

    return concatenatedSignatureValue;
}

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From source file:at.asitplus.regkassen.core.base.util.CryptoUtil.java

License:Apache License

/**
 * Helper method to convert DER-encoded signature values (e.g. used by Java) to concatenated signature values
 * (as used by the JWS-standard)// ww w  . j  a  va  2  s .  com
 *
 * @param derEncodedSignatureValue DER-encoded signature value
 * @return concatenated signature value (as used by JWS standard)
 * @throws IOException
 */
public static byte[] convertDEREncodedSignatureToJWSConcatenated(byte[] derEncodedSignatureValue)
        throws IOException {
    ASN1InputStream asn1InputStream = new ASN1InputStream(derEncodedSignatureValue);
    ASN1Primitive asn1Primitive = asn1InputStream.readObject();
    ASN1Sequence asn1Sequence = (ASN1Sequence.getInstance(asn1Primitive));
    ASN1Integer rASN1 = (ASN1Integer) asn1Sequence.getObjectAt(0);
    ASN1Integer sASN1 = (ASN1Integer) asn1Sequence.getObjectAt(1);
    X9IntegerConverter x9IntegerConverter = new X9IntegerConverter();
    byte[] r = x9IntegerConverter.integerToBytes(rASN1.getValue(), 32);
    byte[] s = x9IntegerConverter.integerToBytes(sASN1.getValue(), 32);

    byte[] concatenatedSignatureValue = new byte[64];
    System.arraycopy(r, 0, concatenatedSignatureValue, 0, 32);
    System.arraycopy(s, 0, concatenatedSignatureValue, 32, 32);

    return concatenatedSignatureValue;
}

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From source file:com.google.bitcoin.core.ECKey.java

License:Apache License

/** Decompress a compressed public key (x co-ord and low-bit of y-coord). */
private static ECPoint decompressKey(BigInteger xBN, boolean yBit) {
    X9IntegerConverter x9 = new X9IntegerConverter();
    byte[] compEnc = x9.integerToBytes(xBN, 1 + x9.getByteLength(CURVE.getCurve()));
    compEnc[0] = (byte) (yBit ? 0x03 : 0x02);
    return CURVE.getCurve().decodePoint(compEnc);
}

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