Desk Checked

Clojure and MessageDigest

June 22nd, 2009

Last night I needed a quick and dirty SHA function for a clojure-based web application. MessageDigest to the rescue!

(ns com.deskchecked.utils
  (:use clojure.contrib.str-utils)
  (:import [java.security MessageDigest]))

(defn sha
  "Generates a SHA-256 hash of the given input plaintext."
  [input]
  (let [md (MessageDigest/getInstance "SHA-256")]
    (. md update (.getBytes input))
    (let [digest (.digest md)]
      (str-join "" (map #(Integer/toHexString (bit-and % 0xff)) digest)))))

There’s obviously a dependency on clojure-contrib here which you can do away with if you don’t need it. And of course, you can pick a hashing algorithm to suit your needs.

Nothing exciting, but I figure I can’t be the only person in need of this sort of stuff.

Categories: Functional Programming, Software Development |