Is there an AES library for clojure?

Question

Is there an AES encryption library for clojure? should I use a java libray available through maven or clojars? Thank your for your time and consideration.

Answer 1

Here is a perhaps more idiomatic example using the available java crypto libraries. encrypt and decrypt here each simply take input text and the encryption key, both as Strings.

(import (javax.crypto Cipher KeyGenerator SecretKey)
        (javax.crypto.spec SecretKeySpec)
        (java.security SecureRandom)
        (org.apache.commons.codec.binary Base64))

(defn bytes [s]
  (.getBytes s "UTF-8"))

(defn base64 [b]
  (Base64/encodeBase64String b))

(defn debase64 [s]
  (Base64/decodeBase64 (bytes s)))

(defn get-raw-key [seed]
  (let [keygen (KeyGenerator/getInstance "AES")
        sr (SecureRandom/getInstance "SHA1PRNG")]
    (.setSeed sr (bytes seed))
    (.init keygen 128 sr)
    (.. keygen generateKey getEncoded)))

(defn get-cipher [mode seed]
  (let [key-spec (SecretKeySpec. (get-raw-key seed) "AES")
        cipher (Cipher/getInstance "AES")]
    (.init cipher mode key-spec)
    cipher))

(defn encrypt [text key]
  (let [bytes (bytes text)
        cipher (get-cipher Cipher/ENCRYPT_MODE key)]
    (base64 (.doFinal cipher bytes))))

(defn decrypt [text key]
  (let [cipher (get-cipher Cipher/DECRYPT_MODE key)]
    (String. (.doFinal cipher (debase64 text)))))

Used suchwise:

(def key "secret key")
(def encrypted (encrypt "My Secret" key)) ;; => "YsuYVJK+Q6E36WjNBeZZdg=="
(decrypt encrypted key) ;; => "My Secret"

Answer 2

Java's AES implementation is well-tested and included in the JDK…any Clojure library would likely use that impl itself.

See Java 256-bit AES Password-Based Encryption for a decent discussion of the Java API. Also, http://jyliao.blogspot.com/2010/08/exploring-java-aes-encryption-algorithm.html has an example of using the API from Clojure (though the code there isn't entirely idiomatic).

Answer 3

Tinklj is a great library that is wrapping Clojure around the Google Tink Java API. Google Tink supports all forms of encryption/decryption using streaming or deterministic. AES is supported AeadKeyTemplates.AES128_GCM.

It also offers MAC and Digital Signatures well worth checking out and getting involved.

For example:

(:require [tinklj.keys.keyset-handle :as keyset-handles])

(keyset-handles/generate-new :aes128-gcm)

(:require [tinklj.encryption.aead :refer [encrypt decrypt])

(encrypt aead (.getBytes data-to-encrypt) aad)
(decrypt aead encrypted aad)

Answer 4

The encryption library Clojure-AES is written entirely in Clojure. The only dependency is on Clojure 1.10 (as of Nov 2021), and it does not utilize any Java-based libraries. Feel free to try it out. It was coded directly from the original NIST specification.