Spring MVC : On the fly encryption/decryption for 2 columns in db

问题

I am working on a Spring-MVC application which uses Hibernate as the ORM and PostgreSQL as the database, in which I am looking for on-the-fly encryption decryption solution, but only for 2 columns in the database, the rest all can stay non-encrypted. I have a Person entity, which has a password and I am encrypting the password with BCrypt and saving them in database.
- If possible, I would like to use this password to encrypt/decrypt those 2 columns once the user logs in and does action on those 2 columns.
- As I am using Spring-Security too, I am injecting the encoder bean so Spring-Security can login the user. Here is how I am saving the password and my security-application-context. As I am just starting with this problem, not that much progress to paste here :

Person entity :

@Entity
@Table(name="person")
public class Person implements UserDetails{


@Id
@Column(name="id")
@GeneratedValue(strategy = GenerationType.SEQUENCE,generator = "person_seq_gen")
@SequenceGenerator(name = "person_seq_gen",sequenceName = "person_seq")
private int id;

 @Valid
    @Email
    @Pattern(regexp = emailRegexp)
    @Column(name = "username")
    private String username;

@Valid
@NotEmpty(message = "Password may not be empty")
@Column(name = "password")
private String password;

// getters and setters ommitted }

PersonServiceImpl :

  @Override
    @Transactional
    public boolean addPerson(Person p) {

        Person existingUser = personDAO.findPersonByUsername(p.getUsername());
        if(existingUser == null) {
            this.personDAO.addPerson(p);
            p.setAccountstatus(false);
            p.setOnetimeemail(false);
            p.setUsername(p.getUsername().toLowerCase());
// as you can see I am encrypting the password and saving in DB, I don't know how to access the plain password at this point to use in some algorithm for on-the-fly encryption/decryption
            p.setPassword(BCrypt.hashpw(p.getPassword(), BCrypt.gensalt(11)));
            p.setUsername(p.getUsername().toLowerCase());
            this.personDAO.addPerson(p);
            sendAccountActivationEmail(p.getUsername(), p.getFirstName());
            return true;
        } else {
            return  false;
        }
    }

Security-application-context.xml :

<beans:bean id="encoder"
                class="org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder">
        <beans:constructor-arg name="strength" value="11" />
    </beans:bean>

    <beans:bean id="daoAuthenticationProvider"
                class="org.springframework.security.authentication.dao.DaoAuthenticationProvider">
                <beans:property name="userDetailsService" ref="LoginServiceImpl"/>
               <beans:property name="passwordEncoder" ref="encoder"/>
    </beans:bean>

Any pointers, help would be nice. If there is anything unclear, kindly let me know. Thanks a lot.

来源：https://stackoverflow.com/questions/28810059/spring-mvc-on-the-fly-encryption-decryption-for-2-columns-in-db

标签

java

hibernate

spring-mvc

encryption

cryptography