How to Hash String using SHA-1 with key?

Question

The time I used to develop applications on iPhone I was converting String to SHA1 with two combination:

• Data
• Key

Now I am developing an Android application and I did not any example for how to calculate SHA1 With key.

I am greatly appreciative of any guidance or help.

---

[The code that I currently use]

private void convertStringToSHA1()
{
        String sTimeStamp  = new SimpleDateFormat("MM/dd/yyyy HH:MM:SS").format(new java.util.Date());
        String sStringToHash = String.format("%1$s\n%2$s", "Username",sTimeStamp);

        MessageDigest cript = MessageDigest.getInstance("SHA-1");
        cript.reset();

        cript.update(sStringToHash.getBytes("utf-8"));
        sStringToHash = new BigInteger(1, cript.digest()).toString(16);
}

Solution

Try something like that:

private String sha1(String s, String keyString) throws UnsupportedEncodingException, NoSuchAlgorithmException, InvalidKeyException {

SecretKeySpec key = new SecretKeySpec((keyString).getBytes("UTF-8"), "HmacSHA1");
Mac mac = Mac.getInstance("HmacSHA1");
mac.init(key);

byte[] bytes = mac.doFinal(s.getBytes("UTF-8"));

return new String( Base64.encodeBase64(bytes));

}

SecretKeySpec docs.

Comments

[thejh]

What code did you use for that conversion?

[Bozho]

SHA-1 with key .. is HMAC? what is the purpose of this?

[Ahmad Kayyali]

@ thejh i am updating the answer right a way.

[Ahmad Kayyali]

Thank you very much for the response, but Base64.encodeBase64 is imported from android.util.Base64 or org.kobjects.base64? thanks in advance.

[Ahmad Kayyali]

Just to let you know the API android.util.Base64 does not have the method you mentioned i used : android.util.Base64.encode(bytes, 0)

[evilone]

In my example this is imported from org.apache.commons.codec.binary and you can download it from commons.apache.org/codec/download_codec.cgi