Java tutorial
/* * The MIT License * * Copyright 2016 Ahseya. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package com.github.horrorho.inflatabledonkey.data.der; import java.util.Arrays; import java.util.Map; import java.util.Objects; import java.util.Optional; import net.jcip.annotations.Immutable; import org.bouncycastle.asn1.ASN1EncodableVector; import org.bouncycastle.asn1.ASN1Integer; import org.bouncycastle.asn1.ASN1Object; import org.bouncycastle.asn1.ASN1OctetString; import org.bouncycastle.asn1.ASN1Primitive; import org.bouncycastle.asn1.DERBitString; import org.bouncycastle.asn1.DEROctetString; import org.bouncycastle.asn1.DERSequence; import org.bouncycastle.asn1.DERTaggedObject; import org.bouncycastle.util.encoders.Hex; /** * SEC1 EC private key. * * @author Ahseya */ @Immutable public final class SECPrivateKey extends ASN1Object { private static final int PARAMETERS = 0; private static final int PUBLIC_KEY = 0; /* SEC 1 ECPrivateKey ::= SEQUENCE { version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1), privateKey OCTET STRING, parameters [0] Parameters OPTIONAL, publicKey [1] BIT STRING OPTIONAL } */ private final int version; private final byte[] privateKey; private final Optional<byte[]> parameters; private final Optional<byte[]> publicKey; public SECPrivateKey(int version, byte[] privateKey, Optional<byte[]> parameters, Optional<byte[]> publicKey) { this.version = Objects.requireNonNull(version, "version"); this.privateKey = Objects.requireNonNull(privateKey, "privateKey"); this.parameters = Objects.requireNonNull(parameters, "parameters"); this.publicKey = Objects.requireNonNull(publicKey, "publicKey"); } public SECPrivateKey(ASN1Primitive primitive) { DERIterator i = DER.asSequence(primitive); Map<Integer, ASN1Primitive> tagged = i.derTaggedObjects(); version = DER.as(ASN1Integer.class, i).getValue().intValue(); privateKey = DER.as(DEROctetString.class, i).getOctets(); parameters = Optional.ofNullable(tagged.get(PARAMETERS)).map(DER.as(DEROctetString.class)) .map(ASN1OctetString::getOctets); publicKey = Optional.ofNullable(tagged.get(PUBLIC_KEY)).map(DER.as(DERBitString.class)) .map(DERBitString::getBytes); } public int version() { return version; } public byte[] privateKey() { return Arrays.copyOf(privateKey, privateKey.length); } public Optional<byte[]> parameters() { return parameters.map(a -> Arrays.copyOf(a, a.length)); } public Optional<byte[]> publicKey() { return publicKey.map(a -> Arrays.copyOf(a, a.length)); } @Override public ASN1Primitive toASN1Primitive() { DERTaggedObject parametersEncodable = parameters().map(DEROctetString::new) .map(e -> new DERTaggedObject(PARAMETERS, e)).orElseGet(null); DERTaggedObject publicKeyEncodable = publicKey().map(DERBitString::new) .map(e -> new DERTaggedObject(PUBLIC_KEY, e)).orElseGet(null); ASN1EncodableVector vector = DER.vector(new ASN1Integer(version), new DEROctetString(privateKey), parametersEncodable, publicKeyEncodable); return new DERSequence(vector); } @Override public String toString() { return "SECPrivateKey{" + "version=" + version + ", privateKey=" + Hex.toHexString(privateKey) + ", parameters=" + parameters.map(Hex::toHexString).orElse(null) + ", publicKey=" + publicKey.map(Hex::toHexString).orElse(null) + '}'; } }