From 46611904ba384b66520e4660d40bda302ffc195d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=CC=88rg=20Prante?= <joergprante@gmail.com>
Date: Tue, 19 Apr 2022 17:28:30 +0200
Subject: [PATCH] adding PBKDF2_SHA256 from 389-ds

---
 .../org/xbib/groovy/crypt/CryptUtil.groovy    | 58 ++++++++++++++++++-
 .../xbib/groovy/crypt/test/CryptTest.groovy   |  8 +++
 2 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/groovy-crypt/src/main/groovy/org/xbib/groovy/crypt/CryptUtil.groovy b/groovy-crypt/src/main/groovy/org/xbib/groovy/crypt/CryptUtil.groovy
index 715e653..daba2e8 100644
--- a/groovy-crypt/src/main/groovy/org/xbib/groovy/crypt/CryptUtil.groovy
+++ b/groovy-crypt/src/main/groovy/org/xbib/groovy/crypt/CryptUtil.groovy
@@ -1,7 +1,11 @@
 package org.xbib.groovy.crypt
 
 import javax.crypto.Mac
+import javax.crypto.SecretKeyFactory
+import javax.crypto.spec.PBEKeySpec
 import javax.crypto.spec.SecretKeySpec
+import java.nio.ByteBuffer
+import java.nio.ByteOrder
 import java.nio.charset.StandardCharsets
 import java.security.MessageDigest
 import java.security.NoSuchAlgorithmException
@@ -79,6 +83,33 @@ class CryptUtil {
         base64Digest(plainText, salt, 'SHA-512', 'ssha512')
     }
 
+    static String pbkdf2(String plainText) {
+        // the 389-ds parameters for PBKDF2-SHA256
+        pbkdf2(plainText, randomHexString(64), 30000, 256)
+    }
+
+    static String pbkdf2(String plainText, String salt) {
+        // the 389-ds parameters for PBKDF2-SHA256: 30000 iterations, 64 bytes (128 hex) salt, 256 bytes hash length
+        if (salt.length() != 128) {
+            throw new IllegalArgumentException("salt must be 64 bytes")
+        }
+        pbkdf2(plainText, salt, 30000, 256)
+    }
+
+    static String pbkdf2(String plainText, String salt, int iterations, int hashLength) {
+        byte[] n = htonl(iterations).array() // 4 bytes for network byte order = native byte order
+        byte[] b = salt.decodeHex()
+        byte[] hash = pbkdf2(plainText.toCharArray(), b, iterations, hashLength * 8)
+        int len = n.length + b .length + hash.length
+        byte[] result = new byte[len]
+        ByteBuffer buffer = ByteBuffer.wrap(result)
+        buffer.put(n)
+        buffer.put(b)
+        buffer.put(hash)
+        // 4 + 64 + 256 = 324 bytes
+        "{PBKDF2_SHA256}${result.encodeBase64()}"
+    }
+
     static String hmacSHA1(String plainText, String secret) {
         hmac(plainText.getBytes(StandardCharsets.UTF_8), secret.getBytes(StandardCharsets.UTF_8), "HmacSHA1")
     }
@@ -105,9 +136,32 @@ class CryptUtil {
         mac.doFinal(plainText).encodeHex()
     }
 
-    static String random(int length) {
+    /**
+     *  Computes the PBKDF2 hash of a password.
+     *
+     * @param   password    the password to hash.
+     * @param   salt        the salt
+     * @param   iterations  the iteration count (slowness factor)
+     * @param   bytes       the length of the hash to compute in bytes
+     * @return              the PBDKF2 hash of the password
+     */
+    static byte[] pbkdf2(char[] plainText, byte[] salt, int iterations, int len) {
+        PBEKeySpec spec = new PBEKeySpec(plainText, salt, iterations, len)
+        SecretKeyFactory skf = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256")
+        skf.generateSecret(spec).getEncoded()
+    }
+
+    static String randomHexString(int length) {
+        randomBytes(length).encodeHex()
+    }
+
+    static byte[] randomBytes(int length) {
         byte[] b = new byte[length]
         random.nextBytes(b)
-        b.encodeHex()
+        b
+    }
+
+    static ByteBuffer htonl(int value) {
+        ByteBuffer.allocate(4).order(ByteOrder.nativeOrder()).putInt(value)
     }
 }
diff --git a/groovy-crypt/src/test/groovy/org/xbib/groovy/crypt/test/CryptTest.groovy b/groovy-crypt/src/test/groovy/org/xbib/groovy/crypt/test/CryptTest.groovy
index c30fd84..ed01b34 100644
--- a/groovy-crypt/src/test/groovy/org/xbib/groovy/crypt/test/CryptTest.groovy
+++ b/groovy-crypt/src/test/groovy/org/xbib/groovy/crypt/test/CryptTest.groovy
@@ -169,4 +169,12 @@ class CryptTest {
         String code = CryptUtil.ssha512(plaintext, salt)
         assertEquals('{ssha512}jeWuCXRjsvKh/vK548GP9ZCs4q9Sh1u700C8eONyV+EL/P810C8vlx9Eu4vRjHq/TDoGW8FE1l/P2KG3w9lHITxo8fR/Qdgv', code,'test SSHA-512 method')
     }
+
+    @Test
+    void testPBKDF2() {
+        String plaintext = 'geheim'
+        String salt = "3c68f1f47f41d82f3c68f1f47f41d82f3c68f1f47f41d82f3c68f1f47f41d82f3c68f1f47f41d82f3c68f1f47f41d82f3c68f1f47f41d82f3c68f1f47f41d82f"
+        String code = CryptUtil.pbkdf2(plaintext, salt)
+        assertEquals("{PBKDF2_SHA256}MHUAADxo8fR/QdgvPGjx9H9B2C88aPH0f0HYLzxo8fR/QdgvPGjx9H9B2C88aPH0f0HYLzxo8fR/QdgvPGjx9H9B2C9DUj6t+vF3mSI5b6nExWWcUnA6DXTbEa25BIMZ5ERe9JIqjkBr2p0ot9D5x4LZx9evQNexOWb+ea/stJkmi3wWKwS/uzSpEc4NZSv/+W1ZWtnK6NMkxxRJPjXEOCrjbKCOktDwCjSelBAe/rt0DABUYoMw69c8qZ1toAIz1x6oN5y58ImMpVsPK/CkbmbeK0QtDbWYZK8V1SZ6cZlF6kngpGWnAcEilIHqCVjM1HZMI+mZz86h86ZHcbxp9twuENu3DHi3nIZRzILrRIsjWAkruSDw7W/jXseGmVeBj/22xbKSybZmXawFGM59k3U5fE+1WvudOfVzwFyVAxDxispF", code)
+    }
 }