Implement Stream ciphers: Salsa20 crypto_stream_xsalsa20_xor

src/main/java/org/abstractj/kalium/NaCl.java

@@ -413,7 +413,14 @@ int crypto_scalarmult_curve25519(
         // ---------------------------------------------------------------------
         // Advanced: Stream ciphers: Salsa20
 
-        // TODO
+        int CRYPTO_STREAM_KEYBYTES = 32;
+
+        int CRYPTO_STREAM_NONCEBYTES = 24;
+
+        int crypto_stream_xor(
+                @Out byte[] result, @In byte[] message,
+                @In @u_int64_t int mlen,
+                @In byte[] nonce, @In byte[] key);
 
         // ---------------------------------------------------------------------
         // Advanced: Stream ciphers: XSalsa20

src/main/java/org/abstractj/kalium/crypto/Advanced.java

@@ -0,0 +1,34 @@
+/**
+ * Copyright 2013 Bruno Oliveira, and individual contributors
+ * <p/>
+ * 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
+ * <p/>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p/>
+ * 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.abstractj.kalium.crypto;
+
+import static org.abstractj.kalium.NaCl.Sodium.CRYPTO_STREAM_KEYBYTES;
+import static org.abstractj.kalium.NaCl.Sodium.CRYPTO_STREAM_NONCEBYTES;
+import static org.abstractj.kalium.NaCl.sodium;
+import static org.abstractj.kalium.crypto.Util.checkLength;
+
+public class Advanced {
+
+    public byte[] crypto_stream_xsalsa20_xor(byte[] message, byte[] nonce, byte[] key) {
+
+        checkLength(nonce, CRYPTO_STREAM_NONCEBYTES);
+        checkLength(key, CRYPTO_STREAM_KEYBYTES);
+        byte[] buffer = new byte[message.length];
+        sodium().crypto_stream_xor(buffer, message, message.length, nonce, key);
+        return buffer;
+
+    }
+}

src/test/java/org/abstractj/kalium/crypto/AdvancedTest.java

@@ -0,0 +1,82 @@
+/**
+ * Copyright 2013 Bruno Oliveira, and individual contributors
+ * <p/>
+ * 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
+ * <p/>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p/>
+ * 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.abstractj.kalium.crypto;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+
+public class AdvancedTest {
+
+    @Test
+    public void testXsalsa20HappyFlow() {
+        Random random = new Random();
+        Advanced advanced = new Advanced();
+        byte[] nonce = random.randomBytes(24);
+        byte[] key = random.randomBytes(32);
+        String pwd = "This is a test message :-)...";
+        byte[] plaintext = pwd.getBytes();
+        byte[] ciphertext = advanced.crypto_stream_xsalsa20_xor(plaintext, nonce, key); // encrypt
+        plaintext = advanced.crypto_stream_xsalsa20_xor(ciphertext, nonce, key); // decrypt
+        assertEquals(pwd, new String(plaintext));
+    }
+
+    @Test
+    public void testXsalsa20IncorrectNonce() {
+        Random random = new Random();
+        Advanced advanced = new Advanced();
+        byte[] nonce = random.randomBytes(24);
+        byte[] incorrectNonce = random.randomBytes(24);
+        byte[] key = random.randomBytes(32);
+        String pwd = "This is a test message :-)...";
+        byte[] plaintext = pwd.getBytes();
+        byte[] ciphertext = advanced.crypto_stream_xsalsa20_xor(plaintext, nonce, key); // encrypt
+        plaintext = advanced.crypto_stream_xsalsa20_xor(ciphertext, incorrectNonce, key); // decrypt
+        assertNotEquals(pwd, new String(plaintext));
+    }
+
+    @Test
+    public void testXsalsa20IncorrectKey() {
+        Random random = new Random();
+        Advanced advanced = new Advanced();
+        byte[] nonce = random.randomBytes(24);
+        byte[] key = random.randomBytes(32);
+        byte[] incorrectKey = random.randomBytes(32);
+        String pwd = "This is a test message :-)...";
+        byte[] plaintext = pwd.getBytes();
+        byte[] ciphertext = advanced.crypto_stream_xsalsa20_xor(plaintext, nonce, key); // encrypt
+        plaintext = advanced.crypto_stream_xsalsa20_xor(ciphertext, nonce, incorrectKey); // decrypt
+        assertNotEquals(pwd, new String(plaintext));
+    }
+
+    @Test
+    public void testXsalsa20IncorrectKeyAndIncorrectNonce() {
+        Random random = new Random();
+        Advanced advanced = new Advanced();
+        byte[] nonce = random.randomBytes(24);
+        byte[] incorrectNonce = random.randomBytes(24);
+        byte[] key = random.randomBytes(32);
+        byte[] incorrectKey = random.randomBytes(32);
+        String pwd = "This is a test message :-)...";
+        byte[] plaintext = pwd.getBytes();
+        byte[] ciphertext = advanced.crypto_stream_xsalsa20_xor(plaintext, nonce, key); // encrypt
+        plaintext = advanced.crypto_stream_xsalsa20_xor(ciphertext, incorrectNonce, incorrectKey); // decrypt
+        assertNotEquals(pwd, new String(plaintext));
+    }
+
+}