add sha3-256

mkyong · mkyong · commit bb686c5ddfa2 · 2020-06-16T19:02:59.000+08:00
diff --git a/java-crypto/src/main/java/com/mkyong/crypto/hash/ShaUtils.java b/java-crypto/src/main/java/com/mkyong/crypto/hash/ShaUtils.java
@@ -0,0 +1,96 @@
+package com.mkyong.crypto.hash;
+
+import com.mkyong.crypto.utils.CryptoUtils;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.security.DigestInputStream;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+public class ShaUtils {
+
+    private static final Charset UTF_8 = StandardCharsets.UTF_8;
+    private static final String OUTPUT_FORMAT = "%-20s:%s";
+
+    public static byte[] digest(byte[] input, String algorithm) {
+        MessageDigest md;
+        try {
+            md = MessageDigest.getInstance(algorithm);
+        } catch (NoSuchAlgorithmException e) {
+            throw new IllegalArgumentException(e);
+        }
+        byte[] result = md.digest(input);
+        return result;
+    }
+
+    private static byte[] checksum(String filePath, String algorithm) {
+
+        MessageDigest md;
+        try {
+            md = MessageDigest.getInstance(algorithm);
+        } catch (NoSuchAlgorithmException e) {
+            throw new IllegalArgumentException(e);
+        }
+
+        try (InputStream is = new FileInputStream(filePath);
+             DigestInputStream dis = new DigestInputStream(is, md)) {
+            while (dis.read() != -1) ; //empty loop to clear the data
+            md = dis.getMessageDigest();
+        } catch (IOException e) {
+            throw new IllegalArgumentException(e);
+        }
+        return md.digest();
+
+    }
+
+    public static String bytesToHex(byte[] bytes) {
+        StringBuilder sb = new StringBuilder();
+        for (byte b : bytes) {
+            sb.append(String.format("%02x", b));
+        }
+        return sb.toString();
+    }
+
+    public static void main(String[] args) {
+
+        //String algorithm = "SHA-256";
+        String algorithm = "SHA3-256";
+
+        String pText = "Hello World";
+        System.out.println(String.format(OUTPUT_FORMAT, "Input (string)", pText));
+        System.out.println(String.format(OUTPUT_FORMAT, "Input (length)", pText.length()));
+
+        byte[] shaInBytes = ShaUtils.digest(pText.getBytes(UTF_8), algorithm);
+        System.out.println(String.format(OUTPUT_FORMAT, algorithm + " (hex) ", bytesToHex(shaInBytes)));
+
+        System.out.println(String.format(OUTPUT_FORMAT, algorithm + " (length)", shaInBytes.length));
+
+        // get file path from resources
+        /*String filePath = ClassLoader.getSystemResource("sha-file.txt").getFile();
+
+        byte[] hashInBytes = checksum(filePath, algorithm);
+        System.out.println(bytesToHex(hashInBytes));*/
+
+        // get a 16 bytes random salt.
+        /*byte[] salt = CryptoUtils.getRandomNonce(16);
+        byte[] pText = "Hello World".getBytes(StandardCharsets.UTF_8);
+
+        // combine two byte arrays
+        byte[] input = ByteBuffer.allocate(salt.length + pText.length)
+                .put(salt)
+                .put(pText)
+                .array();
+
+        // no salt, SHA3-256
+        System.out.println(bytesToHex(ShaUtils.digest(pText, "SHA3-256")));
+
+        // 16 bytes salt, SHA3-256
+        System.out.println(bytesToHex(ShaUtils.digest(input, "SHA3-256")));*/
+
+    }
+}
diff --git a/java-crypto/src/main/resources/sha-file.txt b/java-crypto/src/main/resources/sha-file.txt
@@ -0,0 +1 @@
+Hello World
