在java中使用密钥计算HMAC-SHA512

我想兴奋地构建一个函数，它生成一个带有密钥的HMAC，就像这个站点提供的：

http://www.freeformatter.com/hmac-generator.html

java 8 lib只提供MessageDigest和KeyGenerator，它们最多只支持SH256。

谷歌也没有给我任何结果来生成HMAC。

有人知道实施吗？

我有这个代码生成一个普通的SH256，但我想这对我没什么帮助：

public static String get_SHA_512_SecurePassword(String passwordToHash) throws Exception { String generatedPassword = null; MessageDigest md = MessageDigest.getInstance("SHA-512"); byte[] bytes = md.digest(passwordToHash.getBytes("UTF-8")); StringBuilder sb = new StringBuilder(); for (int i = 0; i < bytes.length; i++) { sb.append(Integer.toString((bytes[i] & 0xff) + 0x100, 16).substring(1)); } generatedPassword = sb.toString(); System.out.println(generatedPassword); return generatedPassword; } 

Answer 1

希望这可以帮助：

 import java.io.UnsupportedEncodingException; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import javax.crypto.Mac; import javax.crypto.spec.SecretKeySpec; public class Test1 { public static void main(String[] args) { Mac sha512_HMAC = null; String result = null; String key = "Welcome1"; try{ byte [] byteKey = key.getBytes("UTF-8"); final String HMAC_SHA512 = "HmacSHA512"; sha512_HMAC = Mac.getInstance(HMAC_SHA512); SecretKeySpec keySpec = new SecretKeySpec(byteKey, HMAC_SHA512); sha512_HMAC.init(keySpec); byte [] mac_data = sha512_HMAC. doFinal("My message".getBytes("UTF-8")); //result = Base64.encode(mac_data); result = bytesToHex(mac_data); System.out.println(result); } catch (UnsupportedEncodingException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (NoSuchAlgorithmException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (InvalidKeyException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally{ System.out.println("Done"); } } public static String bytesToHex(byte[] bytes) { final char[] hexArray = "0123456789ABCDEF".toCharArray(); char[] hexChars = new char[bytes.length * 2]; for ( int j = 0; j < bytes.length; j++ ) { int v = bytes[j] & 0xFF; hexChars[j * 2] = hexArray[v >>> 4]; hexChars[j * 2 + 1] = hexArray[v & 0x0F]; } return new String(hexChars); } } 

要从字节数组转换为hex，请参阅此stackoverflow应答： 此处

Answer 2

最简单的方法是 –

 private static final String HMAC_SHA512 = "HmacSHA512"; private static String toHexString(byte[] bytes) { Formatter formatter = new Formatter(); for (byte b : bytes) { formatter.format("%02x", b); } return formatter.toString(); } public static String calculateHMAC(String data, String key) throws SignatureException, NoSuchAlgorithmException, InvalidKeyException { SecretKeySpec secretKeySpec = new SecretKeySpec(key.getBytes(), HMAC_SHA512); Mac mac = Mac.getInstance(HMAC_SHA512); mac.init(secretKeySpec); return toHexString(mac.doFinal(data.getBytes())); } public static void main(String[] args) throws Exception { String hmac = calculateHMAC("data", "key"); System.out.println(hmac); } 

您可以将HMAC_SHA512变量更改为任何Mac算法，代码将以相同的方式工作。