org.springframework.security.crypto.password.MessageDigestPasswordEncoder Maven / Gradle / Ivy
/*
* Copyright 2002-2018 the original author or authors.
*
* 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
*
* https://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.springframework.security.crypto.password;
import org.springframework.security.crypto.codec.Hex;
import org.springframework.security.crypto.codec.Utf8;
import org.springframework.security.crypto.keygen.Base64StringKeyGenerator;
import org.springframework.security.crypto.keygen.StringKeyGenerator;
import java.security.MessageDigest;
import java.util.Base64;
/**
* This {@link PasswordEncoder} is provided for legacy purposes only and is not considered secure.
*
* Encodes passwords using the passed in {@link MessageDigest}.
*
* The general format of the password is:
*
*
* s = salt == null ? "" : "{" + salt + "}"
* s + digest(password + s)
*
*
* Such that "salt" is the salt, digest is the digest method, and password is the actual
* password. For example when using MD5, a password of "password", and a salt of
* "thisissalt":
*
*
* String s = salt == null ? "" : "{" + salt + "}";
* s + md5(password + s)
* "{thisissalt}" + md5(password + "{thisissalt}")
* "{thisissalt}2a4e7104c2780098f50ed5a84bb2323d"
*
*
* If the salt does not exist, then omit "{salt}" like this:
*
*
* digest(password)
*
*
* If the salt is an empty String, then only use "{}" like this:
*
*
* "{}" + digest(password + "{}")
*
*
* The format is intended to work with the DigestPasswordEncoder that was found in the
* Spring Security core module. However, the passwords will need to be migrated to include
* any salt with the password since this API provides Salt internally vs making it the
* responsibility of the user. To migrate passwords from the SaltSource use the following:
*
*
* String salt = saltSource.getSalt(user);
* String s = salt == null ? null : "{" + salt + "}";
* String migratedPassword = s + user.getPassword();
*
*
* @author Ray Krueger
* @author Luke Taylor
* @author Rob Winch
* @since 5.0
* @deprecated Digest based password encoding is not considered secure. Instead use an
* adaptive one way function like BCryptPasswordEncoder, Pbkdf2PasswordEncoder, or
* SCryptPasswordEncoder. Even better use {@link DelegatingPasswordEncoder} which supports
* password upgrades. There are no plans to remove this support. It is deprecated to indicate
* that this is a legacy implementation and using it is considered insecure.
*/
@Deprecated
public class MessageDigestPasswordEncoder implements PasswordEncoder {
private static final String PREFIX = "{";
private static final String SUFFIX = "}";
private StringKeyGenerator saltGenerator = new Base64StringKeyGenerator();
private boolean encodeHashAsBase64;
private Digester digester;
/**
* The digest algorithm to use Supports the named
*
* Message Digest Algorithms in the Java environment.
*
* @param algorithm
*/
public MessageDigestPasswordEncoder(String algorithm) {
this.digester = new Digester(algorithm, 1);
}
public void setEncodeHashAsBase64(boolean encodeHashAsBase64) {
this.encodeHashAsBase64 = encodeHashAsBase64;
}
/**
* Encodes the rawPass using a MessageDigest. If a salt is specified it will be merged
* with the password before encoding.
*
* @param rawPassword The plain text password
* @return Hex string of password digest (or base64 encoded string if
* encodeHashAsBase64 is enabled.
*/
public String encode(CharSequence rawPassword) {
String salt = PREFIX + this.saltGenerator.generateKey() + SUFFIX;
return digest(salt, rawPassword);
}
private String digest(String salt, CharSequence rawPassword) {
String saltedPassword = rawPassword + salt;
byte[] digest = this.digester.digest(Utf8.encode(saltedPassword));
String encoded = encode(digest);
return salt + encoded;
}
private String encode(byte[] digest) {
if (this.encodeHashAsBase64) {
return Utf8.decode(Base64.getEncoder().encode(digest));
}
else {
return new String(Hex.encode(digest));
}
}
/**
* Takes a previously encoded password and compares it with a rawpassword after mixing
* in the salt and encoding that value
*
* @param rawPassword plain text password
* @param encodedPassword previously encoded password
* @return true or false
*/
public boolean matches(CharSequence rawPassword, String encodedPassword) {
String salt = extractSalt(encodedPassword);
String rawPasswordEncoded = digest(salt, rawPassword);
return PasswordEncoderUtils.equals(encodedPassword.toString(), rawPasswordEncoded);
}
/**
* Sets the number of iterations for which the calculated hash value should be
* "stretched". If this is greater than one, the initial digest is calculated, the
* digest function will be called repeatedly on the result for the additional number
* of iterations.
*
* @param iterations the number of iterations which will be executed on the hashed
* password/salt value. Defaults to 1.
*/
public void setIterations(int iterations) {
this.digester.setIterations(iterations);
}
private String extractSalt(String prefixEncodedPassword) {
int start = prefixEncodedPassword.indexOf(PREFIX);
if (start != 0) {
return "";
}
int end = prefixEncodedPassword.indexOf(SUFFIX, start);
if (end < 0) {
return "";
}
return prefixEncodedPassword.substring(start, end + 1);
}
}