package com.google.bitcoin.bouncycastle.asn1.cmp; import com.google.bitcoin.bouncycastle.asn1.ASN1Encodable; import com.google.bitcoin.bouncycastle.asn1.ASN1EncodableVector; import com.google.bitcoin.bouncycastle.asn1.ASN1OctetString; import com.google.bitcoin.bouncycastle.asn1.ASN1Sequence; import com.google.bitcoin.bouncycastle.asn1.DERObject; import com.google.bitcoin.bouncycastle.asn1.DERSequence; import com.google.bitcoin.bouncycastle.asn1.x509.AlgorithmIdentifier; public class Challenge extends ASN1Encodable { private AlgorithmIdentifier owf; private ASN1OctetString witness; private ASN1OctetString challenge; private Challenge(ASN1Sequence seq) { int index = 0; if (seq.size() == 3) { owf = AlgorithmIdentifier.getInstance(seq.getObjectAt(index++)); } witness = ASN1OctetString.getInstance(seq.getObjectAt(index++)); challenge = ASN1OctetString.getInstance(seq.getObjectAt(index)); } public static Challenge getInstance(Object o) { if (o instanceof Challenge) { return (Challenge)o; } if (o instanceof ASN1Sequence) { return new Challenge((ASN1Sequence)o); } throw new IllegalArgumentException("Invalid object: " + o.getClass().getName()); } public AlgorithmIdentifier getOwf() { return owf; } /** * <pre> * Challenge ::= SEQUENCE { * owf AlgorithmIdentifier OPTIONAL, * * -- MUST be present in the first Challenge; MAY be omitted in * -- any subsequent Challenge in POPODecKeyChallContent (if * -- omitted, then the owf used in the immediately preceding * -- Challenge is to be used). * * witness OCTET STRING, * -- the result of applying the one-way function (owf) to a * -- randomly-generated INTEGER, A. [Note that a different * -- INTEGER MUST be used for each Challenge.] * challenge OCTET STRING * -- the encryption (under the public key for which the cert. * -- request is being made) of Rand, where Rand is specified as * -- Rand ::= SEQUENCE { * -- int INTEGER, * -- - the randomly-generated INTEGER A (above) * -- sender GeneralName * -- - the sender's name (as included in PKIHeader) * -- } * } * </pre> * @return a basic ASN.1 object representation. */ public DERObject toASN1Object() { ASN1EncodableVector v = new ASN1EncodableVector(); addOptional(v, owf); v.add(witness); v.add(challenge); return new DERSequence(v); } private void addOptional(ASN1EncodableVector v, ASN1Encodable obj) { if (obj != null) { v.add(obj); } } }