org.unitedid.auth.client.factors.PasswordFactor.java Source code

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Here is the source code for org.unitedid.auth.client.factors.PasswordFactor.java

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/*
 * Copyright (c) 2014 United ID.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.unitedid.auth.client.factors;

import com.google.gson.annotations.Expose;
import com.google.gson.annotations.SerializedName;
import org.springframework.security.crypto.bcrypt.BCrypt;
import org.unitedid.auth.client.factors.impl.Factor;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;

public class PasswordFactor extends Factor {
    @Expose
    @SerializedName("H1")
    private String passwordHash;
    private String salt;

    public PasswordFactor(String password, String credentialId)
            throws NoSuchAlgorithmException, UnsupportedEncodingException {
        this(password, credentialId, 10);
    }

    public PasswordFactor(String password, String credentialId, int rounds)
            throws UnsupportedEncodingException, NoSuchAlgorithmException {
        this(password, credentialId, BCrypt.gensalt(rounds));
    }

    public PasswordFactor(String password, String credentialId, String salt)
            throws UnsupportedEncodingException, NoSuchAlgorithmException {
        this.type = "password";
        this.credentialId = credentialId;
        this.salt = salt;
        String bcryptHash = BCrypt.hashpw(sha256PreHash(password), salt);
        passwordHash = bcryptHash.substring(salt.length());
    }

    public String getSalt() {
        return salt;
    }

    public String getPasswordHash() {
        return passwordHash;
    }

    /**
     * Due to limitations of BCrypt() max password length of 55 characters we pre hash the password using
     * sha256 before passing it onto BCrypt() to allow for longer passwords.
     *
     * @param password
     * @return
     * @throws NoSuchAlgorithmException
     * @throws UnsupportedEncodingException
     */
    private String sha256PreHash(String password) throws NoSuchAlgorithmException, UnsupportedEncodingException {
        String result = "";
        MessageDigest digest = MessageDigest.getInstance("SHA-256");
        byte[] hash = digest.digest(password.getBytes("UTF-8"));

        for (int i = 0; i < hash.length; i++) {
            result += Integer.toString((hash[i] & 0xff) + 0x100, 16).substring(1);
        }

        return result;
    }

    public String getRandomNonce() throws NoSuchAlgorithmException {
        SecureRandom rand = SecureRandom.getInstance("SHA1PRNG");
        byte[] randomBytes = new byte[6];
        rand.nextBytes(randomBytes);

        String result = "";
        for (int i = 0; i < randomBytes.length; i++) {
            result += Integer.toString((randomBytes[i] & 0xff) + 0x100, 16).substring(1);
        }

        return result;
    }

    public Boolean verify(String plaintext, String hash)
            throws UnsupportedEncodingException, NoSuchAlgorithmException {
        return BCrypt.checkpw(sha256PreHash(plaintext), hash);
    }

    /*@Override
    public String toString() {
    return "PasswordFactor [H1=" + passwordHash
            + ", type=" + credentialType
            + ", credentialId=" + credentialId +"]";
    } */

    @Override
    public String toString() {
        return null; //To change body of implemented methods use File | Settings | File Templates.
    }
}