Add argon2 hash function

Co-authored-by: Soulflyer <[email protected]>

Add deps.edn

Fix bad url in README

Remove unrelated code

Co-authored-by: Iain Wood <[email protected]>

Remove more unrelated code

Co-authored-by: Iain Wood <[email protected]>

Fix README and docstrings length

Fix format

README.md

@@ -8,6 +8,7 @@ A Clojure library for securing user passwords using a
 * [PBKDF2](http://en.wikipedia.org/wiki/PBKDF2)
 * [Bcrypt](http://bcrypt.sourceforge.net/)
 * [scrypt](http://www.tarsnap.com/scrypt.html)
+* [argon2](https://github.com/phxql/argon2-jvm)
 
 [1]: http://en.wikipedia.org/wiki/Key_derivation_function
 
@@ -19,7 +20,8 @@ Add the following dependency to your `project.clj` file:
 
 ## Usage
 
-Pick an encryption algorithm, either `pbkdf2`, `bcrypt` or `scrypt`:
+Pick an encryption algorithm, either `pbkdf2`, `bcrypt`, `scrypt`
+or `argon2`:
 
 ```clojure
 (require '[crypto.password.<algorithm> :as password])

project.clj

@@ -8,7 +8,8 @@
                  [crypto-equality "1.0.0"]
                  [commons-codec "1.15"]
                  [at.favre.lib/bcrypt "0.9.0"]
-                 [com.lambdaworks/scrypt "1.4.0"]]
+                 [com.lambdaworks/scrypt "1.4.0"]
+                 [de.mkammerer/argon2-jvm "2.11"]]
   :plugins [[lein-codox "0.9.4"]]
   :codox
   {:output-path "codox"

src/crypto/password/argon2.clj

@@ -0,0 +1,38 @@
+(ns crypto.password.argon2
+ "Functions for encrypting passwords using the recommended argon2 algorithm.
+
+  See: https://infosecscout.com/best-algorithm-password-storage
+  https://github.com/phxql/argon2-jvm"
+ (:import [de.mkammerer.argon2 Argon2 Argon2Factory Argon2Advanced]))
+
+(def argon2 (Argon2Factory/create))
+
+(def ^:private default-iterations
+  (Long/parseLong (System/getProperty "crypto.password.argon2.default-iterations" "22")))
+
+(def ^:private default-memory-cost
+  (Long/parseLong (System/getProperty "crypto.password.argon2.default-memory-cost" "65536")))
+
+(def ^:private default-parallelization-parameter
+  (Long/parseLong (System/getProperty "crypto.password.argon2.default-parallelization-parameter" "1")))
+
+(defn encrypt
+  "Encrypt a password string using the argon2 algorithm. This function takes
+  three optional parameters:
+
+  * `iter`     - the number of iterations, defaults to 22
+  * `mem`      - the memory cost, defaults to 65536
+  * `parallel` - the parallelization parameter, defaults to 1"
+  ([raw]
+   (encrypt raw
+            default-iterations
+            default-memory-cost
+            default-parallelization-parameter))
+  ([raw iter mem parallel]
+   (.hash argon2 iter mem parallel raw)))
+
+(defn check
+  "Compare a raw string with a string encrypted with the [[encrypt]]
+  function. Returns true if the string matches, false otherwise."
+  [raw hash]
+  (.verify argon2 hash raw))

test/crypto/password/argon2_test.clj

@@ -0,0 +1,20 @@
+(ns crypto.password.argon2-test
+  (:require [clojure.test :refer [deftest are]]
+            [crypto.password.argon2 :as password]))
+
+(deftest test-passwords
+  (are [s] (password/check s (password/encrypt s))
+    "a"
+    "foo"
+    "password"
+    "Testing"
+    "Test123"
+    "ÁäñßOÔ"
+    "großpösna"
+    "Some rather long pass phrase perhaps out of a book or poem")
+
+  (are [s r] (not (password/check r (password/encrypt s)))
+    "a" "b"
+    "a" "a "
+    "aaaaa" "aaaaa\n"
+    "großpösna" "grossposna"))