org.bouncycastle.bcpg.sig.NotationData Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of bcpg-lts8on Show documentation

The Bouncy Castle Java APIs for the OpenPGP Protocol. The APIs are designed primarily to be used in conjunction with the BC LTS provider but may also be used with other providers providing cryptographic services.

The newest version!

package org.bouncycastle.bcpg.sig;

import java.io.ByteArrayOutputStream;

import org.bouncycastle.bcpg.SignatureSubpacket;
import org.bouncycastle.bcpg.SignatureSubpacketTags;
import org.bouncycastle.util.Strings;

/**
 * Signature Subpacket encoding custom notations.
 * Notations are key-value pairs.
 *
 * @see 
 *     RFC4880 - Notation Data
 * @see 
 *     RFC9580 - Notation Data
 */
public class NotationData
    extends SignatureSubpacket
{
    public static final int HEADER_FLAG_LENGTH = 4;
    public static final int HEADER_NAME_LENGTH = 2;
    public static final int HEADER_VALUE_LENGTH = 2;

    public NotationData(
        boolean critical,
        boolean isLongLength,
        byte[] data)
    {
        super(SignatureSubpacketTags.NOTATION_DATA, critical, isLongLength, data);
    }

    public NotationData(
        boolean critical,
        boolean humanReadable,
        String notationName,
        String notationValue)
    {
        super(SignatureSubpacketTags.NOTATION_DATA, critical, false, createData(humanReadable, notationName, notationValue));
    }

    private static byte[] createData(boolean humanReadable, String notationName, String notationValue)
    {
        ByteArrayOutputStream out = new ByteArrayOutputStream();

//        (4 octets of flags, 2 octets of name length (M),
//        2 octets of value length (N),
//        M octets of name data,
//        N octets of value data)

        // flags
        out.write(humanReadable ? 0x80 : 0x00);
        out.write(0x0);
        out.write(0x0);
        out.write(0x0);

        byte[] nameData, valueData = null;
        int nameLength, valueLength;

        nameData = Strings.toUTF8ByteArray(notationName);
        nameLength = Math.min(nameData.length, 0xFFFF);

        if (nameLength != nameData.length)
        {
            throw new IllegalArgumentException("notationName exceeds maximum length.");
        }

        valueData = Strings.toUTF8ByteArray(notationValue);
        valueLength = Math.min(valueData.length, 0xFFFF);
        if (valueLength != valueData.length)
        {
            throw new IllegalArgumentException("notationValue exceeds maximum length.");
        }

        // name length
        out.write((nameLength >>> 8) & 0xFF);
        out.write((nameLength >>> 0) & 0xFF);

        // value length
        out.write((valueLength >>> 8) & 0xFF);
        out.write((valueLength >>> 0) & 0xFF);

        // name
        out.write(nameData, 0, nameLength);

        // value
        out.write(valueData, 0, valueLength);

        return out.toByteArray();
    }

    public boolean isHumanReadable()
    {
        return data[0] == (byte)0x80;
    }

    public String getNotationName()
    {
        int nameLength = (((data[HEADER_FLAG_LENGTH] & 0xff) << 8) + (data[HEADER_FLAG_LENGTH + 1] & 0xff));

        byte[] bName = new byte[nameLength];
        System.arraycopy(data, HEADER_FLAG_LENGTH + HEADER_NAME_LENGTH + HEADER_VALUE_LENGTH, bName, 0, nameLength);

        return Strings.fromUTF8ByteArray(bName);
    }

    public String getNotationValue()
    {
        return Strings.fromUTF8ByteArray(getNotationValueBytes());
    }

    public byte[] getNotationValueBytes()
    {
        int nameLength = (((data[HEADER_FLAG_LENGTH] & 0xff) << 8) + (data[HEADER_FLAG_LENGTH + 1] & 0xff));
        int valueLength = (((data[HEADER_FLAG_LENGTH + HEADER_NAME_LENGTH] & 0xff) << 8) + (data[HEADER_FLAG_LENGTH + HEADER_NAME_LENGTH + 1] & 0xff));

        byte[] bValue = new byte[valueLength];
        System.arraycopy(data, HEADER_FLAG_LENGTH + HEADER_NAME_LENGTH + HEADER_VALUE_LENGTH + nameLength, bValue, 0, valueLength);
        return bValue;
    }
}