package pl.edu.mimuw.cloudatlas.querysigner; import pl.edu.mimuw.cloudatlas.ByteSerializer; import pl.edu.mimuw.cloudatlas.model.ValueQuery; import pl.edu.mimuw.cloudatlas.querysignerapi.QuerySignerApi; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import javax.crypto.NoSuchPaddingException; import java.rmi.RemoteException; import java.security.*; import java.util.HashMap; import java.util.HashSet; import java.util.Map; import java.util.Set; public class QuerySignerApiImplementation implements QuerySignerApi { private final static String ENCRYPTION_ALGORITHM = "RSA"; private final static String DIGEST_ALGORITHM = "SHA-256"; private PublicKey publicKey; private PrivateKey privateKey; private Map queries; private Set attribsSetByQueries; private ByteSerializer byteSerializer; QuerySignerApiImplementation(PublicKey publicKey, PrivateKey privateKey) { this.byteSerializer = new ByteSerializer(); this.publicKey = publicKey; this.privateKey = privateKey; this.queries = new HashMap<>(); this.attribsSetByQueries = new HashSet<>(); } private String byteArrayToString(byte[] arr, int offset, int len) { StringBuffer sb = new StringBuffer(); for (int i = offset, n = Math.min(arr.length, offset + len); i < n; ++i) { String hex = Integer.toHexString(0xFF & arr[i]); if (hex.length() < 2) { sb.append('0'); } sb.append(hex); } return sb.toString(); } private byte[] encryptQuery(byte[] query) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException { Cipher signCipher = Cipher.getInstance(ENCRYPTION_ALGORITHM); signCipher.init(Cipher.ENCRYPT_MODE, privateKey); byte[] encryptedBytes = signCipher.doFinal(query); System.out.println( "Bytes encrypted with " + ENCRYPTION_ALGORITHM + ": " + byteArrayToString( encryptedBytes, 0, encryptedBytes.length)); return encryptedBytes; } private byte[] decryptQuery(byte[] encryptedQuery) throws NoSuchPaddingException, NoSuchAlgorithmException, BadPaddingException, IllegalBlockSizeException, InvalidKeyException { Cipher verifyCipher = Cipher.getInstance(ENCRYPTION_ALGORITHM); verifyCipher.init(Cipher.DECRYPT_MODE, publicKey); byte[] decryptedBytes = verifyCipher.doFinal(encryptedQuery); System.out.println( "Bytes decrypted with " + ENCRYPTION_ALGORITHM + ": " + byteArrayToString( decryptedBytes, 0, decryptedBytes.length)); return decryptedBytes; } private byte[] cryptographicHash(byte[] serializedQuery) throws NoSuchAlgorithmException { MessageDigest digestGenerator = MessageDigest.getInstance(DIGEST_ALGORITHM); byte[] digest = digestGenerator.digest(serializedQuery); System.out.println( DIGEST_ALGORITHM + " digest: " + byteArrayToString( digest, 0, digest.length)); return digest; } private byte[] serializeQuery(String queryName, String queryCode) { return byteSerializer.serialize(queryName + queryCode); } @Override public QueryData signInstallQuery(String queryName, String queryCode) throws RemoteException { QueryUtils.validateQueryName(queryName); try { byte[] serializedQuery = serializeQuery(queryName, queryCode); byte[] hashedQuery = cryptographicHash(serializedQuery); byte[] querySignature = encryptQuery(hashedQuery); return new QueryData(queryCode, querySignature); } catch (Exception e) { e.printStackTrace(); throw new RemoteException(e.getLocalizedMessage()); } } @Override public void validateInstallQuery(String queryName, QueryData query) throws RemoteException { QueryUtils.validateQueryName(queryName); try { byte[] decryptedQuery = decryptQuery(query.getSignature()); byte[] serializedQuery = serializeQuery(queryName, query.getCode()); byte[] hashedSerializedQuery = cryptographicHash(serializedQuery); if (hashedSerializedQuery != decryptedQuery) { throw new QuerySigner.InvalidQueryException(); } } catch (NoSuchPaddingException | NoSuchAlgorithmException | BadPaddingException | IllegalBlockSizeException | InvalidKeyException | QuerySigner.InvalidQueryException e) { e.printStackTrace(); throw new RemoteException(e.getLocalizedMessage()); } } // TODO @Override public QueryData signUninstallQuery(String queryName) throws RemoteException { return null; } // TODO @Override public void validateUninstallQuery(String queryName, QueryData query) throws RemoteException { } }