Examples with AlgorithmIdentifier com.github.zhenwei.core.asn1.x509.AlgorithmIdentifier used on opensource projects

Example 1 with AlgorithmIdentifier

use of com.github.zhenwei.core.asn1.x509.AlgorithmIdentifier in project kafka by apache.

the class TestSslUtils method generateCertificate.

/**
     * Create a self-signed X.509 Certificate.
     * From http://bfo.com/blog/2011/03/08/odds_and_ends_creating_a_new_x_509_certificate.html.
     *
     * @param dn the X.509 Distinguished Name, eg "CN=Test, L=London, C=GB"
     * @param pair the KeyPair
     * @param days how many days from now the Certificate is valid for
     * @param algorithm the signing algorithm, eg "SHA1withRSA"
     * @return the self-signed certificate
     * @throws CertificateException thrown if a security error or an IO error occurred.
     */
public static X509Certificate generateCertificate(String dn, KeyPair pair, int days, String algorithm) throws CertificateException {
    try {
        Security.addProvider(new BouncyCastleProvider());
        AlgorithmIdentifier sigAlgId = new DefaultSignatureAlgorithmIdentifierFinder().find(algorithm);
        AlgorithmIdentifier digAlgId = new DefaultDigestAlgorithmIdentifierFinder().find(sigAlgId);
        AsymmetricKeyParameter privateKeyAsymKeyParam = PrivateKeyFactory.createKey(pair.getPrivate().getEncoded());
        SubjectPublicKeyInfo subPubKeyInfo = SubjectPublicKeyInfo.getInstance(pair.getPublic().getEncoded());
        ContentSigner sigGen = new BcRSAContentSignerBuilder(sigAlgId, digAlgId).build(privateKeyAsymKeyParam);
        X500Name name = new X500Name(dn);
        Date from = new Date();
        Date to = new Date(from.getTime() + days * 86400000L);
        BigInteger sn = new BigInteger(64, new SecureRandom());
        X509v1CertificateBuilder v1CertGen = new X509v1CertificateBuilder(name, sn, from, to, name, subPubKeyInfo);
        X509CertificateHolder certificateHolder = v1CertGen.build(sigGen);
        return new JcaX509CertificateConverter().setProvider("BC").getCertificate(certificateHolder);
    } catch (CertificateException ce) {
        throw ce;
    } catch (Exception e) {
        throw new CertificateException(e);
    }
}

Example 2 with AlgorithmIdentifier

use of com.github.zhenwei.core.asn1.x509.AlgorithmIdentifier in project XobotOS by xamarin.

the class X509CertSelector method match.

/**
     * Returns whether the specified certificate matches all the criteria
     * collected in this instance.
     *
     * @param certificate
     *            the certificate to check.
     * @return {@code true} if the certificate matches all the criteria,
     *         otherwise {@code false}.
     */
public boolean match(Certificate certificate) {
    if (!(certificate instanceof X509Certificate)) {
        return false;
    }
    X509Certificate cert = (X509Certificate) certificate;
    if ((certificateEquals != null) && !certificateEquals.equals(cert)) {
        return false;
    }
    if ((serialNumber != null) && !serialNumber.equals(cert.getSerialNumber())) {
        return false;
    }
    if ((issuer != null) && !issuer.equals(cert.getIssuerX500Principal())) {
        return false;
    }
    if ((subject != null) && !subject.equals(cert.getSubjectX500Principal())) {
        return false;
    }
    if ((subjectKeyIdentifier != null) && !Arrays.equals(subjectKeyIdentifier, // are taken from rfc 3280 (http://www.ietf.org/rfc/rfc3280.txt)
    getExtensionValue(cert, "2.5.29.14"))) {
        return false;
    }
    if ((authorityKeyIdentifier != null) && !Arrays.equals(authorityKeyIdentifier, getExtensionValue(cert, "2.5.29.35"))) {
        return false;
    }
    if (certificateValid != null) {
        try {
            cert.checkValidity(certificateValid);
        } catch (CertificateExpiredException e) {
            return false;
        } catch (CertificateNotYetValidException e) {
            return false;
        }
    }
    if (privateKeyValid != null) {
        try {
            byte[] bytes = getExtensionValue(cert, "2.5.29.16");
            if (bytes == null) {
                return false;
            }
            PrivateKeyUsagePeriod pkup = (PrivateKeyUsagePeriod) PrivateKeyUsagePeriod.ASN1.decode(bytes);
            Date notBefore = pkup.getNotBefore();
            Date notAfter = pkup.getNotAfter();
            if ((notBefore == null) && (notAfter == null)) {
                return false;
            }
            if ((notBefore != null) && notBefore.compareTo(privateKeyValid) > 0) {
                return false;
            }
            if ((notAfter != null) && notAfter.compareTo(privateKeyValid) < 0) {
                return false;
            }
        } catch (IOException e) {
            return false;
        }
    }
    if (subjectPublicKeyAlgID != null) {
        try {
            byte[] encoding = cert.getPublicKey().getEncoded();
            AlgorithmIdentifier ai = ((SubjectPublicKeyInfo) SubjectPublicKeyInfo.ASN1.decode(encoding)).getAlgorithmIdentifier();
            if (!subjectPublicKeyAlgID.equals(ai.getAlgorithm())) {
                return false;
            }
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
    }
    if (subjectPublicKey != null) {
        if (!Arrays.equals(subjectPublicKey, cert.getPublicKey().getEncoded())) {
            return false;
        }
    }
    if (keyUsage != null) {
        boolean[] ku = cert.getKeyUsage();
        if (ku != null) {
            int i = 0;
            int min_length = (ku.length < keyUsage.length) ? ku.length : keyUsage.length;
            for (; i < min_length; i++) {
                if (keyUsage[i] && !ku[i]) {
                    // but certificate does not.
                    return false;
                }
            }
            for (; i < keyUsage.length; i++) {
                if (keyUsage[i]) {
                    return false;
                }
            }
        }
    }
    if (extendedKeyUsage != null) {
        try {
            List keyUsage = cert.getExtendedKeyUsage();
            if (keyUsage != null) {
                if (!keyUsage.containsAll(extendedKeyUsage)) {
                    return false;
                }
            }
        } catch (CertificateParsingException e) {
            return false;
        }
    }
    if (pathLen != -1) {
        int p_len = cert.getBasicConstraints();
        if ((pathLen < 0) && (p_len >= 0)) {
            // need end-entity but got CA
            return false;
        }
        if ((pathLen > 0) && (pathLen > p_len)) {
            // allowed _pathLen is small
            return false;
        }
    }
    if (subjectAltNames != null) {
        PASSED: try {
            byte[] bytes = getExtensionValue(cert, "2.5.29.17");
            if (bytes == null) {
                return false;
            }
            List<GeneralName> sans = ((GeneralNames) GeneralNames.ASN1.decode(bytes)).getNames();
            if ((sans == null) || (sans.size() == 0)) {
                return false;
            }
            boolean[][] map = new boolean[9][];
            // initialize the check map
            for (int i = 0; i < 9; i++) {
                map[i] = (subjectAltNames[i] == null) ? EmptyArray.BOOLEAN : new boolean[subjectAltNames[i].size()];
            }
            for (GeneralName name : sans) {
                int tag = name.getTag();
                for (int i = 0; i < map[tag].length; i++) {
                    if (subjectAltNames[tag].get(i).equals(name)) {
                        if (!matchAllNames) {
                            break PASSED;
                        }
                        map[tag][i] = true;
                    }
                }
            }
            if (!matchAllNames) {
                // there was not any match
                return false;
            }
            // else check the map
            for (int tag = 0; tag < 9; tag++) {
                for (int name = 0; name < map[tag].length; name++) {
                    if (!map[tag][name]) {
                        return false;
                    }
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
    }
    if (nameConstraints != null) {
        if (!nameConstraints.isAcceptable(cert)) {
            return false;
        }
    }
    if (policies != null) {
        byte[] bytes = getExtensionValue(cert, "2.5.29.32");
        if (bytes == null) {
            return false;
        }
        if (policies.size() == 0) {
            // one policy in it.
            return true;
        }
        PASSED: try {
            List<PolicyInformation> policyInformations = ((CertificatePolicies) CertificatePolicies.ASN1.decode(bytes)).getPolicyInformations();
            for (PolicyInformation policyInformation : policyInformations) {
                if (policies.contains(policyInformation.getPolicyIdentifier())) {
                    break PASSED;
                }
            }
            return false;
        } catch (IOException e) {
            // the extension is invalid
            return false;
        }
    }
    if (pathToNames != null) {
        byte[] bytes = getExtensionValue(cert, "2.5.29.30");
        if (bytes != null) {
            NameConstraints nameConstraints;
            try {
                nameConstraints = (NameConstraints) NameConstraints.ASN1.decode(bytes);
            } catch (IOException e) {
                // the extension is invalid;
                return false;
            }
            if (!nameConstraints.isAcceptable(pathToNames)) {
                return false;
            }
        }
    }
    return true;
}

Example 3 with AlgorithmIdentifier

use of com.github.zhenwei.core.asn1.x509.AlgorithmIdentifier in project XobotOS by xamarin.

the class JCEECPublicKey method getEncoded.

public byte[] getEncoded() {
    ASN1Encodable params;
    SubjectPublicKeyInfo info;
    // BEGIN android-removed
    // if (algorithm.equals("ECGOST3410"))
    // {
    //     if (gostParams != null)
    //     {
    //         params = gostParams;
    //     }
    //     else
    //     {
    //         if (ecSpec instanceof ECNamedCurveSpec)
    //         {
    //             params = new GOST3410PublicKeyAlgParameters(
    //                            ECGOST3410NamedCurves.getOID(((ECNamedCurveSpec)ecSpec).getName()),
    //                            CryptoProObjectIdentifiers.gostR3411_94_CryptoProParamSet);
    //         }
    //         else
    //         {   // strictly speaking this may not be applicable...
    //             ECCurve curve = EC5Util.convertCurve(ecSpec.getCurve());
    //
    //             X9ECParameters ecP = new X9ECParameters(
    //                 curve,
    //                 EC5Util.convertPoint(curve, ecSpec.getGenerator(), withCompression),
    //                 ecSpec.getOrder(),
    //                 BigInteger.valueOf(ecSpec.getCofactor()),
    //                 ecSpec.getCurve().getSeed());
    //
    //             params = new X962Parameters(ecP);
    //         }
    //     }
    //
    //     BigInteger      bX = this.q.getX().toBigInteger();
    //     BigInteger      bY = this.q.getY().toBigInteger();
    //     byte[]          encKey = new byte[64];
    //
    //     extractBytes(encKey, 0, bX);
    //     extractBytes(encKey, 32, bY);
    //
    //     info = new SubjectPublicKeyInfo(new AlgorithmIdentifier(CryptoProObjectIdentifiers.gostR3410_2001, params.getDERObject()), new DEROctetString(encKey));
    // }
    // else
    // END android-removed
    {
        if (ecSpec instanceof ECNamedCurveSpec) {
            DERObjectIdentifier curveOid = ECUtil.getNamedCurveOid(((ECNamedCurveSpec) ecSpec).getName());
            if (curveOid == null) {
                curveOid = new DERObjectIdentifier(((ECNamedCurveSpec) ecSpec).getName());
            }
            params = new X962Parameters(curveOid);
        } else if (ecSpec == null) {
            params = new X962Parameters(DERNull.INSTANCE);
        } else {
            ECCurve curve = EC5Util.convertCurve(ecSpec.getCurve());
            X9ECParameters ecP = new X9ECParameters(curve, EC5Util.convertPoint(curve, ecSpec.getGenerator(), withCompression), ecSpec.getOrder(), BigInteger.valueOf(ecSpec.getCofactor()), ecSpec.getCurve().getSeed());
            params = new X962Parameters(ecP);
        }
        ECCurve curve = this.engineGetQ().getCurve();
        ASN1OctetString p = (ASN1OctetString) new X9ECPoint(curve.createPoint(this.getQ().getX().toBigInteger(), this.getQ().getY().toBigInteger(), withCompression)).getDERObject();
        info = new SubjectPublicKeyInfo(new AlgorithmIdentifier(X9ObjectIdentifiers.id_ecPublicKey, params.getDERObject()), p.getOctets());
    }
    return info.getDEREncoded();
}

Example 4 with AlgorithmIdentifier

use of com.github.zhenwei.core.asn1.x509.AlgorithmIdentifier in project XobotOS by xamarin.

the class JDKPKCS12KeyStore method doStore.

private void doStore(OutputStream stream, char[] password, boolean useDEREncoding) throws IOException {
    if (password == null) {
        throw new NullPointerException("No password supplied for PKCS#12 KeyStore.");
    }
    //
    // handle the key
    //
    ASN1EncodableVector keyS = new ASN1EncodableVector();
    Enumeration ks = keys.keys();
    while (ks.hasMoreElements()) {
        byte[] kSalt = new byte[SALT_SIZE];
        random.nextBytes(kSalt);
        String name = (String) ks.nextElement();
        PrivateKey privKey = (PrivateKey) keys.get(name);
        PKCS12PBEParams kParams = new PKCS12PBEParams(kSalt, MIN_ITERATIONS);
        byte[] kBytes = wrapKey(keyAlgorithm.getId(), privKey, kParams, password);
        AlgorithmIdentifier kAlgId = new AlgorithmIdentifier(keyAlgorithm, kParams.getDERObject());
        org.bouncycastle.asn1.pkcs.EncryptedPrivateKeyInfo kInfo = new org.bouncycastle.asn1.pkcs.EncryptedPrivateKeyInfo(kAlgId, kBytes);
        boolean attrSet = false;
        ASN1EncodableVector kName = new ASN1EncodableVector();
        if (privKey instanceof PKCS12BagAttributeCarrier) {
            PKCS12BagAttributeCarrier bagAttrs = (PKCS12BagAttributeCarrier) privKey;
            //
            // make sure we are using the local alias on store
            //
            DERBMPString nm = (DERBMPString) bagAttrs.getBagAttribute(pkcs_9_at_friendlyName);
            if (nm == null || !nm.getString().equals(name)) {
                bagAttrs.setBagAttribute(pkcs_9_at_friendlyName, new DERBMPString(name));
            }
            //
            if (bagAttrs.getBagAttribute(pkcs_9_at_localKeyId) == null) {
                Certificate ct = engineGetCertificate(name);
                bagAttrs.setBagAttribute(pkcs_9_at_localKeyId, createSubjectKeyId(ct.getPublicKey()));
            }
            Enumeration e = bagAttrs.getBagAttributeKeys();
            while (e.hasMoreElements()) {
                DERObjectIdentifier oid = (DERObjectIdentifier) e.nextElement();
                ASN1EncodableVector kSeq = new ASN1EncodableVector();
                kSeq.add(oid);
                kSeq.add(new DERSet(bagAttrs.getBagAttribute(oid)));
                attrSet = true;
                kName.add(new DERSequence(kSeq));
            }
        }
        if (!attrSet) {
            //
            // set a default friendly name (from the key id) and local id
            //
            ASN1EncodableVector kSeq = new ASN1EncodableVector();
            Certificate ct = engineGetCertificate(name);
            kSeq.add(pkcs_9_at_localKeyId);
            kSeq.add(new DERSet(createSubjectKeyId(ct.getPublicKey())));
            kName.add(new DERSequence(kSeq));
            kSeq = new ASN1EncodableVector();
            kSeq.add(pkcs_9_at_friendlyName);
            kSeq.add(new DERSet(new DERBMPString(name)));
            kName.add(new DERSequence(kSeq));
        }
        SafeBag kBag = new SafeBag(pkcs8ShroudedKeyBag, kInfo.getDERObject(), new DERSet(kName));
        keyS.add(kBag);
    }
    byte[] keySEncoded = new DERSequence(keyS).getDEREncoded();
    BERConstructedOctetString keyString = new BERConstructedOctetString(keySEncoded);
    //
    // certificate processing
    //
    byte[] cSalt = new byte[SALT_SIZE];
    random.nextBytes(cSalt);
    ASN1EncodableVector certSeq = new ASN1EncodableVector();
    PKCS12PBEParams cParams = new PKCS12PBEParams(cSalt, MIN_ITERATIONS);
    AlgorithmIdentifier cAlgId = new AlgorithmIdentifier(certAlgorithm, cParams.getDERObject());
    Hashtable doneCerts = new Hashtable();
    Enumeration cs = keys.keys();
    while (cs.hasMoreElements()) {
        try {
            String name = (String) cs.nextElement();
            Certificate cert = engineGetCertificate(name);
            boolean cAttrSet = false;
            CertBag cBag = new CertBag(x509Certificate, new DEROctetString(cert.getEncoded()));
            ASN1EncodableVector fName = new ASN1EncodableVector();
            if (cert instanceof PKCS12BagAttributeCarrier) {
                PKCS12BagAttributeCarrier bagAttrs = (PKCS12BagAttributeCarrier) cert;
                //
                // make sure we are using the local alias on store
                //
                DERBMPString nm = (DERBMPString) bagAttrs.getBagAttribute(pkcs_9_at_friendlyName);
                if (nm == null || !nm.getString().equals(name)) {
                    bagAttrs.setBagAttribute(pkcs_9_at_friendlyName, new DERBMPString(name));
                }
                //
                if (bagAttrs.getBagAttribute(pkcs_9_at_localKeyId) == null) {
                    bagAttrs.setBagAttribute(pkcs_9_at_localKeyId, createSubjectKeyId(cert.getPublicKey()));
                }
                Enumeration e = bagAttrs.getBagAttributeKeys();
                while (e.hasMoreElements()) {
                    DERObjectIdentifier oid = (DERObjectIdentifier) e.nextElement();
                    ASN1EncodableVector fSeq = new ASN1EncodableVector();
                    fSeq.add(oid);
                    fSeq.add(new DERSet(bagAttrs.getBagAttribute(oid)));
                    fName.add(new DERSequence(fSeq));
                    cAttrSet = true;
                }
            }
            if (!cAttrSet) {
                ASN1EncodableVector fSeq = new ASN1EncodableVector();
                fSeq.add(pkcs_9_at_localKeyId);
                fSeq.add(new DERSet(createSubjectKeyId(cert.getPublicKey())));
                fName.add(new DERSequence(fSeq));
                fSeq = new ASN1EncodableVector();
                fSeq.add(pkcs_9_at_friendlyName);
                fSeq.add(new DERSet(new DERBMPString(name)));
                fName.add(new DERSequence(fSeq));
            }
            SafeBag sBag = new SafeBag(certBag, cBag.getDERObject(), new DERSet(fName));
            certSeq.add(sBag);
            doneCerts.put(cert, cert);
        } catch (CertificateEncodingException e) {
            throw new IOException("Error encoding certificate: " + e.toString());
        }
    }
    cs = certs.keys();
    while (cs.hasMoreElements()) {
        try {
            String certId = (String) cs.nextElement();
            Certificate cert = (Certificate) certs.get(certId);
            boolean cAttrSet = false;
            if (keys.get(certId) != null) {
                continue;
            }
            CertBag cBag = new CertBag(x509Certificate, new DEROctetString(cert.getEncoded()));
            ASN1EncodableVector fName = new ASN1EncodableVector();
            if (cert instanceof PKCS12BagAttributeCarrier) {
                PKCS12BagAttributeCarrier bagAttrs = (PKCS12BagAttributeCarrier) cert;
                //
                // make sure we are using the local alias on store
                //
                DERBMPString nm = (DERBMPString) bagAttrs.getBagAttribute(pkcs_9_at_friendlyName);
                if (nm == null || !nm.getString().equals(certId)) {
                    bagAttrs.setBagAttribute(pkcs_9_at_friendlyName, new DERBMPString(certId));
                }
                Enumeration e = bagAttrs.getBagAttributeKeys();
                while (e.hasMoreElements()) {
                    DERObjectIdentifier oid = (DERObjectIdentifier) e.nextElement();
                    // If we find one, we'll prune it out.
                    if (oid.equals(PKCSObjectIdentifiers.pkcs_9_at_localKeyId)) {
                        continue;
                    }
                    ASN1EncodableVector fSeq = new ASN1EncodableVector();
                    fSeq.add(oid);
                    fSeq.add(new DERSet(bagAttrs.getBagAttribute(oid)));
                    fName.add(new DERSequence(fSeq));
                    cAttrSet = true;
                }
            }
            if (!cAttrSet) {
                ASN1EncodableVector fSeq = new ASN1EncodableVector();
                fSeq.add(pkcs_9_at_friendlyName);
                fSeq.add(new DERSet(new DERBMPString(certId)));
                fName.add(new DERSequence(fSeq));
            }
            SafeBag sBag = new SafeBag(certBag, cBag.getDERObject(), new DERSet(fName));
            certSeq.add(sBag);
            doneCerts.put(cert, cert);
        } catch (CertificateEncodingException e) {
            throw new IOException("Error encoding certificate: " + e.toString());
        }
    }
    cs = chainCerts.keys();
    while (cs.hasMoreElements()) {
        try {
            CertId certId = (CertId) cs.nextElement();
            Certificate cert = (Certificate) chainCerts.get(certId);
            if (doneCerts.get(cert) != null) {
                continue;
            }
            CertBag cBag = new CertBag(x509Certificate, new DEROctetString(cert.getEncoded()));
            ASN1EncodableVector fName = new ASN1EncodableVector();
            if (cert instanceof PKCS12BagAttributeCarrier) {
                PKCS12BagAttributeCarrier bagAttrs = (PKCS12BagAttributeCarrier) cert;
                Enumeration e = bagAttrs.getBagAttributeKeys();
                while (e.hasMoreElements()) {
                    DERObjectIdentifier oid = (DERObjectIdentifier) e.nextElement();
                    // If we find one, we'll prune it out.
                    if (oid.equals(PKCSObjectIdentifiers.pkcs_9_at_localKeyId)) {
                        continue;
                    }
                    ASN1EncodableVector fSeq = new ASN1EncodableVector();
                    fSeq.add(oid);
                    fSeq.add(new DERSet(bagAttrs.getBagAttribute(oid)));
                    fName.add(new DERSequence(fSeq));
                }
            }
            SafeBag sBag = new SafeBag(certBag, cBag.getDERObject(), new DERSet(fName));
            certSeq.add(sBag);
        } catch (CertificateEncodingException e) {
            throw new IOException("Error encoding certificate: " + e.toString());
        }
    }
    byte[] certSeqEncoded = new DERSequence(certSeq).getDEREncoded();
    byte[] certBytes = cryptData(true, cAlgId, password, false, certSeqEncoded);
    EncryptedData cInfo = new EncryptedData(data, cAlgId, new BERConstructedOctetString(certBytes));
    ContentInfo[] info = new ContentInfo[] { new ContentInfo(data, keyString), new ContentInfo(encryptedData, cInfo.getDERObject()) };
    AuthenticatedSafe auth = new AuthenticatedSafe(info);
    ByteArrayOutputStream bOut = new ByteArrayOutputStream();
    DEROutputStream asn1Out;
    if (useDEREncoding) {
        asn1Out = new DEROutputStream(bOut);
    } else {
        asn1Out = new BEROutputStream(bOut);
    }
    asn1Out.writeObject(auth);
    byte[] pkg = bOut.toByteArray();
    ContentInfo mainInfo = new ContentInfo(data, new BERConstructedOctetString(pkg));
    //
    // create the mac
    //
    byte[] mSalt = new byte[20];
    int itCount = MIN_ITERATIONS;
    random.nextBytes(mSalt);
    byte[] data = ((ASN1OctetString) mainInfo.getContent()).getOctets();
    MacData mData;
    try {
        byte[] res = calculatePbeMac(id_SHA1, mSalt, itCount, password, false, data);
        // BEGIN android-changed
        AlgorithmIdentifier algId = new AlgorithmIdentifier(id_SHA1, DERNull.INSTANCE);
        // END android-changed
        DigestInfo dInfo = new DigestInfo(algId, res);
        mData = new MacData(dInfo, mSalt, itCount);
    } catch (Exception e) {
        throw new IOException("error constructing MAC: " + e.toString());
    }
    //
    // output the Pfx
    //
    Pfx pfx = new Pfx(mainInfo, mData);
    if (useDEREncoding) {
        asn1Out = new DEROutputStream(stream);
    } else {
        asn1Out = new BEROutputStream(stream);
    }
    asn1Out.writeObject(pfx);
}

Example 5 with AlgorithmIdentifier

use of com.github.zhenwei.core.asn1.x509.AlgorithmIdentifier in project android_frameworks_base by ResurrectionRemix.

the class AndroidKeyStoreKeyPairGeneratorSpi method generateSelfSignedCertificateWithFakeSignature.

@SuppressWarnings("deprecation")
private X509Certificate generateSelfSignedCertificateWithFakeSignature(PublicKey publicKey) throws IOException, CertificateParsingException {
    V3TBSCertificateGenerator tbsGenerator = new V3TBSCertificateGenerator();
    ASN1ObjectIdentifier sigAlgOid;
    AlgorithmIdentifier sigAlgId;
    byte[] signature;
    switch(mKeymasterAlgorithm) {
        case KeymasterDefs.KM_ALGORITHM_EC:
            sigAlgOid = X9ObjectIdentifiers.ecdsa_with_SHA256;
            sigAlgId = new AlgorithmIdentifier(sigAlgOid);
            ASN1EncodableVector v = new ASN1EncodableVector();
            v.add(new DERInteger(0));
            v.add(new DERInteger(0));
            signature = new DERSequence().getEncoded();
            break;
        case KeymasterDefs.KM_ALGORITHM_RSA:
            sigAlgOid = PKCSObjectIdentifiers.sha256WithRSAEncryption;
            sigAlgId = new AlgorithmIdentifier(sigAlgOid, DERNull.INSTANCE);
            signature = new byte[1];
            break;
        default:
            throw new ProviderException("Unsupported key algorithm: " + mKeymasterAlgorithm);
    }
    try (ASN1InputStream publicKeyInfoIn = new ASN1InputStream(publicKey.getEncoded())) {
        tbsGenerator.setSubjectPublicKeyInfo(SubjectPublicKeyInfo.getInstance(publicKeyInfoIn.readObject()));
    }
    tbsGenerator.setSerialNumber(new ASN1Integer(mSpec.getCertificateSerialNumber()));
    X509Principal subject = new X509Principal(mSpec.getCertificateSubject().getEncoded());
    tbsGenerator.setSubject(subject);
    tbsGenerator.setIssuer(subject);
    tbsGenerator.setStartDate(new Time(mSpec.getCertificateNotBefore()));
    tbsGenerator.setEndDate(new Time(mSpec.getCertificateNotAfter()));
    tbsGenerator.setSignature(sigAlgId);
    TBSCertificate tbsCertificate = tbsGenerator.generateTBSCertificate();
    ASN1EncodableVector result = new ASN1EncodableVector();
    result.add(tbsCertificate);
    result.add(sigAlgId);
    result.add(new DERBitString(signature));
    return new X509CertificateObject(Certificate.getInstance(new DERSequence(result)));
}