Examples with ContentInfo org.bouncycastle.asn1.cms.ContentInfo used on opensource projects

Example 11 with ContentInfo

use of org.bouncycastle.asn1.cms.ContentInfo in project XobotOS by xamarin.

the class MiscPEMGenerator method createPemObject.

private PemObject createPemObject(Object o) throws IOException {
    String type;
    byte[] encoding;
    if (o instanceof PemObject) {
        return (PemObject) o;
    }
    if (o instanceof PemObjectGenerator) {
        return ((PemObjectGenerator) o).generate();
    }
    if (o instanceof X509Certificate) {
        type = "CERTIFICATE";
        try {
            encoding = ((X509Certificate) o).getEncoded();
        } catch (CertificateEncodingException e) {
            throw new PemGenerationException("Cannot encode object: " + e.toString());
        }
    } else if (o instanceof X509CRL) {
        type = "X509 CRL";
        try {
            encoding = ((X509CRL) o).getEncoded();
        } catch (CRLException e) {
            throw new PemGenerationException("Cannot encode object: " + e.toString());
        }
    } else if (o instanceof KeyPair) {
        return createPemObject(((KeyPair) o).getPrivate());
    } else if (o instanceof PrivateKey) {
        PrivateKeyInfo info = new PrivateKeyInfo((ASN1Sequence) ASN1Object.fromByteArray(((Key) o).getEncoded()));
        if (o instanceof RSAPrivateKey) {
            type = "RSA PRIVATE KEY";
            encoding = info.getPrivateKey().getEncoded();
        } else if (o instanceof DSAPrivateKey) {
            type = "DSA PRIVATE KEY";
            DSAParameter p = DSAParameter.getInstance(info.getAlgorithmId().getParameters());
            ASN1EncodableVector v = new ASN1EncodableVector();
            v.add(new DERInteger(0));
            v.add(new DERInteger(p.getP()));
            v.add(new DERInteger(p.getQ()));
            v.add(new DERInteger(p.getG()));
            BigInteger x = ((DSAPrivateKey) o).getX();
            BigInteger y = p.getG().modPow(x, p.getP());
            v.add(new DERInteger(y));
            v.add(new DERInteger(x));
            encoding = new DERSequence(v).getEncoded();
        } else if (((PrivateKey) o).getAlgorithm().equals("ECDSA")) {
            type = "EC PRIVATE KEY";
            encoding = info.getPrivateKey().getEncoded();
        } else {
            throw new IOException("Cannot identify private key");
        }
    } else if (o instanceof PublicKey) {
        type = "PUBLIC KEY";
        encoding = ((PublicKey) o).getEncoded();
    } else if (o instanceof X509AttributeCertificate) {
        type = "ATTRIBUTE CERTIFICATE";
        encoding = ((X509V2AttributeCertificate) o).getEncoded();
    } else if (o instanceof PKCS10CertificationRequest) {
        type = "CERTIFICATE REQUEST";
        encoding = ((PKCS10CertificationRequest) o).getEncoded();
    } else if (o instanceof ContentInfo) {
        type = "PKCS7";
        encoding = ((ContentInfo) o).getEncoded();
    } else {
        throw new PemGenerationException("unknown object passed - can't encode.");
    }
    return new PemObject(type, encoding);
}

Example 12 with ContentInfo

use of org.bouncycastle.asn1.cms.ContentInfo in project XobotOS by xamarin.

the class ContentInfo method toASN1Object.

/**
     * Produce an object suitable for an ASN1OutputStream.
     * <pre>
     * ContentInfo ::= SEQUENCE {
     *          contentType ContentType,
     *          content
     *          [0] EXPLICIT ANY DEFINED BY contentType OPTIONAL }
     * </pre>
     */
public DERObject toASN1Object() {
    ASN1EncodableVector v = new ASN1EncodableVector();
    v.add(contentType);
    if (content != null) {
        v.add(new BERTaggedObject(0, content));
    }
    return new BERSequence(v);
}

Example 13 with ContentInfo

use of org.bouncycastle.asn1.cms.ContentInfo in project robovm by robovm.

the class PKCS12KeyStoreSpi 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.toASN1Primitive());
        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()) {
                ASN1ObjectIdentifier oid = (ASN1ObjectIdentifier) 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.toASN1Primitive(), new DERSet(kName));
        keyS.add(kBag);
    }
    byte[] keySEncoded = new DERSequence(keyS).getEncoded(ASN1Encoding.DER);
    BEROctetString keyString = new BEROctetString(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.toASN1Primitive());
    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()) {
                    ASN1ObjectIdentifier oid = (ASN1ObjectIdentifier) 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.toASN1Primitive(), 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()) {
                    ASN1ObjectIdentifier oid = (ASN1ObjectIdentifier) 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.toASN1Primitive(), 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()) {
                    ASN1ObjectIdentifier oid = (ASN1ObjectIdentifier) 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.toASN1Primitive(), new DERSet(fName));
            certSeq.add(sBag);
        } catch (CertificateEncodingException e) {
            throw new IOException("Error encoding certificate: " + e.toString());
        }
    }
    byte[] certSeqEncoded = new DERSequence(certSeq).getEncoded(ASN1Encoding.DER);
    byte[] certBytes = cryptData(true, cAlgId, password, false, certSeqEncoded);
    EncryptedData cInfo = new EncryptedData(data, cAlgId, new BEROctetString(certBytes));
    ContentInfo[] info = new ContentInfo[] { new ContentInfo(data, keyString), new ContentInfo(encryptedData, cInfo.toASN1Primitive()) };
    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 BEROctetString(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);
        AlgorithmIdentifier algId = new AlgorithmIdentifier(id_SHA1, DERNull.INSTANCE);
        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 14 with ContentInfo

use of org.bouncycastle.asn1.cms.ContentInfo in project ddf by codice.

the class KeystoreEditor method addToStore.

private synchronized void addToStore(String alias, String keyPassword, String storePassword, String data, String type, String fileName, String path, String storepass, KeyStore store) throws KeystoreEditorException {
    OutputStream fos = null;
    try (InputStream inputStream = new ByteArrayInputStream(Base64.getDecoder().decode(data))) {
        if (StringUtils.isBlank(alias)) {
            throw new IllegalArgumentException("Alias cannot be null.");
        }
        Path storeFile = Paths.get(path);
        //check the two most common key/cert stores first (pkcs12 and jks)
        if (PKCS12_TYPE.equals(type) || StringUtils.endsWithIgnoreCase(fileName, ".p12")) {
            //priv key + cert chain
            KeyStore pkcs12Store = KeyStore.getInstance("PKCS12");
            pkcs12Store.load(inputStream, storePassword.toCharArray());
            Certificate[] chain = pkcs12Store.getCertificateChain(alias);
            Key key = pkcs12Store.getKey(alias, keyPassword.toCharArray());
            if (key != null) {
                store.setKeyEntry(alias, key, keyPassword.toCharArray(), chain);
                fos = Files.newOutputStream(storeFile);
                store.store(fos, storepass.toCharArray());
            }
        } else if (JKS_TYPE.equals(type) || StringUtils.endsWithIgnoreCase(fileName, ".jks")) {
            //java keystore file
            KeyStore jks = KeyStore.getInstance("jks");
            jks.load(inputStream, storePassword.toCharArray());
            Enumeration<String> aliases = jks.aliases();
            //we are going to store all entries from the jks regardless of the passed in alias
            while (aliases.hasMoreElements()) {
                String jksAlias = aliases.nextElement();
                if (jks.isKeyEntry(jksAlias)) {
                    Key key = jks.getKey(jksAlias, keyPassword.toCharArray());
                    Certificate[] certificateChain = jks.getCertificateChain(jksAlias);
                    store.setKeyEntry(jksAlias, key, keyPassword.toCharArray(), certificateChain);
                } else {
                    Certificate certificate = jks.getCertificate(jksAlias);
                    store.setCertificateEntry(jksAlias, certificate);
                }
            }
            fos = Files.newOutputStream(storeFile);
            store.store(fos, storepass.toCharArray());
        //need to parse der separately from pem, der has the same mime type but is binary hence checking both
        } else if (DER_TYPE.equals(type) && StringUtils.endsWithIgnoreCase(fileName, ".der")) {
            ASN1InputStream asn1InputStream = new ASN1InputStream(inputStream);
            ASN1Primitive asn1Primitive = asn1InputStream.readObject();
            X509CertificateHolder x509CertificateHolder = new X509CertificateHolder(asn1Primitive.getEncoded());
            CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509", "BC");
            Certificate certificate = certificateFactory.generateCertificate(new ByteArrayInputStream(x509CertificateHolder.getEncoded()));
            X500Name x500name = new JcaX509CertificateHolder((X509Certificate) certificate).getSubject();
            RDN cn = x500name.getRDNs(BCStyle.CN)[0];
            String cnStr = IETFUtils.valueToString(cn.getFirst().getValue());
            if (!store.isCertificateEntry(cnStr) && !store.isKeyEntry(cnStr)) {
                store.setCertificateEntry(cnStr, certificate);
            }
            store.setCertificateEntry(alias, certificate);
            fos = Files.newOutputStream(storeFile);
            store.store(fos, storepass.toCharArray());
        //if it isn't one of the stores we support, it might be a key or cert by itself
        } else if (isPemParsable(type, fileName)) {
            //This is the catch all case for PEM, P7B, etc. with common file extensions if the mime type isn't read correctly in the browser
            Reader reader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));
            PEMParser pemParser = new PEMParser(reader);
            Object object;
            boolean setEntry = false;
            while ((object = pemParser.readObject()) != null) {
                if (object instanceof PEMEncryptedKeyPair || object instanceof PEMKeyPair) {
                    PEMKeyPair pemKeyPair;
                    if (object instanceof PEMEncryptedKeyPair) {
                        PEMEncryptedKeyPair pemEncryptedKeyPairKeyPair = (PEMEncryptedKeyPair) object;
                        JcePEMDecryptorProviderBuilder jcePEMDecryptorProviderBuilder = new JcePEMDecryptorProviderBuilder();
                        pemKeyPair = pemEncryptedKeyPairKeyPair.decryptKeyPair(jcePEMDecryptorProviderBuilder.build(keyPassword.toCharArray()));
                    } else {
                        pemKeyPair = (PEMKeyPair) object;
                    }
                    KeyPair keyPair = new JcaPEMKeyConverter().setProvider("BC").getKeyPair(pemKeyPair);
                    PrivateKey privateKey = keyPair.getPrivate();
                    Certificate[] chain = store.getCertificateChain(alias);
                    if (chain == null) {
                        chain = buildCertChain(alias, store);
                    }
                    store.setKeyEntry(alias, privateKey, keyPassword.toCharArray(), chain);
                    setEntry = true;
                } else if (object instanceof X509CertificateHolder) {
                    X509CertificateHolder x509CertificateHolder = (X509CertificateHolder) object;
                    CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509", "BC");
                    Certificate certificate = certificateFactory.generateCertificate(new ByteArrayInputStream(x509CertificateHolder.getEncoded()));
                    X500Name x500name = new JcaX509CertificateHolder((X509Certificate) certificate).getSubject();
                    RDN cn = x500name.getRDNs(BCStyle.CN)[0];
                    String cnStr = IETFUtils.valueToString(cn.getFirst().getValue());
                    if (!store.isCertificateEntry(cnStr) && !store.isKeyEntry(cnStr)) {
                        store.setCertificateEntry(cnStr, certificate);
                    }
                    store.setCertificateEntry(alias, certificate);
                    setEntry = true;
                } else if (object instanceof ContentInfo) {
                    ContentInfo contentInfo = (ContentInfo) object;
                    if (contentInfo.getContentType().equals(CMSObjectIdentifiers.envelopedData)) {
                        CMSEnvelopedData cmsEnvelopedData = new CMSEnvelopedData(contentInfo);
                        OriginatorInfo originatorInfo = cmsEnvelopedData.getOriginatorInfo().toASN1Structure();
                        ASN1Set certificates = originatorInfo.getCertificates();
                        setEntry = importASN1CertificatesToStore(store, setEntry, certificates);
                    } else if (contentInfo.getContentType().equals(CMSObjectIdentifiers.signedData)) {
                        SignedData signedData = SignedData.getInstance(contentInfo.getContent());
                        ASN1Set certificates = signedData.getCertificates();
                        setEntry = importASN1CertificatesToStore(store, setEntry, certificates);
                    }
                } else if (object instanceof PKCS8EncryptedPrivateKeyInfo) {
                    PKCS8EncryptedPrivateKeyInfo pkcs8EncryptedPrivateKeyInfo = (PKCS8EncryptedPrivateKeyInfo) object;
                    Certificate[] chain = store.getCertificateChain(alias);
                    if (chain == null) {
                        chain = buildCertChain(alias, store);
                    }
                    try {
                        store.setKeyEntry(alias, pkcs8EncryptedPrivateKeyInfo.getEncoded(), chain);
                        setEntry = true;
                    } catch (KeyStoreException keyEx) {
                        try {
                            PKCS8Key pkcs8Key = new PKCS8Key(pkcs8EncryptedPrivateKeyInfo.getEncoded(), keyPassword.toCharArray());
                            store.setKeyEntry(alias, pkcs8Key.getPrivateKey(), keyPassword.toCharArray(), chain);
                            setEntry = true;
                        } catch (GeneralSecurityException e) {
                            LOGGER.info("Unable to add PKCS8 key to keystore with secondary method. Throwing original exception.", e);
                            throw keyEx;
                        }
                    }
                }
            }
            if (setEntry) {
                fos = Files.newOutputStream(storeFile);
                store.store(fos, storepass.toCharArray());
            }
        }
    } catch (Exception e) {
        LOGGER.info("Unable to add entry {} to store", alias, e);
        throw new KeystoreEditorException("Unable to add entry " + alias + " to store", e);
    } finally {
        if (fos != null) {
            try {
                fos.close();
            } catch (IOException ignore) {
            }
        }
    }
    init();
}

Example 15 with ContentInfo

use of org.bouncycastle.asn1.cms.ContentInfo in project keystore-explorer by kaikramer.

the class CryptoFileUtil method detectKeyStoreType.

/**
 * Detect the KeyStore type contained in the supplied file.
 *
 * @param is
 *            Input stream to detect type for
 * @return KeyStore type or null if none matched
 * @throws IOException
 *             If an I/O problem occurred
 */
public static KeyStoreType detectKeyStoreType(InputStream is) throws IOException {
    byte[] contents = ReadUtil.readFully(is);
    try (DataInputStream dis = new DataInputStream(new ByteArrayInputStream(contents))) {
        // If less than 4 bytes are available it isn't a KeyStore
        if (dis.available() < 4) {
            return null;
        }
        // Read first integer (4 bytes)
        int i1 = dis.readInt();
        // Test for JKS - starts with appropriate magic number
        if (i1 == JKS_MAGIC_NUMBER) {
            return JKS;
        }
        // Test for JCEKS - starts with appropriate magic number
        if (i1 == JCEKS_MAGIC_NUMBER) {
            return JCEKS;
        }
        // Both start with a version number of 0, 1 or 2
        if ((i1 == 0) || (i1 == 1) || (i1 == 2)) {
            if (contents.length < 26) {
                // Insufficient bytes to be BKS or UBER
                return null;
            }
            // Skip to 21st from last byte (file length minus 21 and the 4 bytes already read)
            dis.skip(contents.length - 25);
            // Read what may be the null byte
            if (dis.readByte() == 0) {
                // Found null byte - BKS/BKS-V1
                if (i1 == 1) {
                    return BKS_V1;
                } else {
                    return BKS;
                }
            } else {
                // No null byte - UBER
                return UBER;
            }
        }
    }
    // @formatter:off
    /*
		 * Test for PKCS #12. ASN.1 should look like this:
		 *
		 * PFX ::= ASN1Sequence { version ASN1Integer {v3(3)}(v3,...), authSafe
		 * ContentInfo, macData MacData OPTIONAL
		 */
    // @formatter:on
    ASN1Primitive pfx = null;
    try {
        pfx = ASN1Primitive.fromByteArray(contents);
    } catch (IOException e) {
        // if it cannot be parsed as ASN1, it is certainly not a pfx key store
        return null;
    }
    // Is a sequence...
    if ((pfx != null) && (pfx instanceof ASN1Sequence)) {
        // Has two or three components...
        ASN1Sequence sequence = (ASN1Sequence) pfx;
        if ((sequence.size() == 2) || (sequence.size() == 3)) {
            // ...the first of which is a version of 3
            ASN1Encodable firstComponent = sequence.getObjectAt(0);
            if (firstComponent instanceof ASN1Integer) {
                ASN1Integer version = (ASN1Integer) firstComponent;
                if (version.getValue().intValue() == 3) {
                    return PKCS12;
                }
            }
        }
    }
    // KeyStore type not recognised
    return null;
}