Does every Android phone support SHA-256

Question

So reading this post: How can I calculate the SHA-256 hash of a string in Android?

and the docs: http://developer.android.com/reference/java/security/MessageDigest.html

I'm curious; which phones will support SHA-256? In the docs, the line about the 'NoSuchAlgorithmException' makes me think that some phones don't support all algorithms. Before I go implementing this for an app and expecting it to work the same on all phones I want to know if anyone knows anything about this...?

I find it strange that the MessageDigest class doesn't have some constants to pick the algorithm you want to use.

Answer 1

All Android devices support SHA-256. The NoSuchAlgorithmException indicates that a requested algorithm could not be found and is necessary because the method takes a String argument for the algorithm name. If you passed in "foo-256", the method's only recourse is to throw a NoSuchAlgorithmException because, for reasons beyond my understanding, there's no algorithm called "foo-256". Assuming you're passing in a name you're sure is an algorithm that Android can use, you'll never see that exception.

Answer 2

Add NoSuchAlgorithmException as below:

public static String SHA256 (String text) throws NoSuchAlgorithmException {      MessageDigest md = MessageDigest.getInstance("SHA-256");      md.update(text.getBytes());     byte[] digest = md.digest();      return Base64.encodeToString(digest, Base64.DEFAULT); }