While implementing authentication using Spring Security, you may get this error when testing login function:

java.lang.IllegalArgumentException: There is no PasswordEncoder mapped for the id "null"

Or null can be any unknown password encoding algorithm.

To fix this error, you need to specify a password encoder explicitly this way:

public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

	@Bean
	public PasswordEncoder passwordEncoder() {
		return new BCryptPasswordEncoder();	
	}
	
	@Override
	protected void configure(AuthenticationManagerBuilder auth) throws Exception {
		...
	}


	@Override
	protected void configure(HttpSecurity http) throws Exception {
		...
	}
}

 

Or, in case you’re using in-memory authentication, specify the password encoder like this:

@Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
	auth.inMemoryAuthentication()
	
		.passwordEncoder(new BCryptPasswordEncoder())
		
		.withUser("namhm").password("$2a$10$fUXt47JTx/Rv/OHBkQgqAOvan445zDU7tCZcHr...")
		.roles("USER")
		;
}

If you are using JDBC, fix the error “there is no PasswordEncoder mapped” as follows:

@Autowired
public void configAuthentication(AuthenticationManagerBuilder auth) throws Exception {

	auth.jdbcAuthentication().passwordEncoder(new BCryptPasswordEncoder());
	
}

 

You may also get the same error if you specify wrong prefix for in-memory password accidentally like this:

@Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
	auth.inMemoryAuthentication()
		.withUser("namhm").password("{bvrypt}$2a$10$fUXt47JTx/Rv/OHBkQgqAOvan445zDU7tCZcHr...")
		.roles("USER")
		;
}

Spring will report this error:

java.lang.IllegalArgumentException: There is no PasswordEncoder mapped for the id "bvrypt"

So to fix this error, you need to correct the prefix, e.g. {bcrypt} is for BCrypt password encoder.

 

Related Spring Security Tutorials:

• Spring Web MVC Security Basic Example Part 1 with XML Configuration
• Spring Web MVC Security Basic Example Part 2 (Java-based Configuration)

 

Other Spring Tutorials:

• Understand the core of Spring framework
• Understand Spring MVC
• Understand Spring AOP
• Spring MVC beginner tutorial with Spring Tool Suite IDE
• Spring MVC Form Handling Tutorial
• Spring MVC Form Validation Tutorial
• 14 Tips for Writing Spring MVC Controller
• Spring Web MVC Security Basic Example (XML Configuration)
• Understand Spring Data JPA with Simple Example