Hill Cipher tests and info added

src/core/lib/HillCipher.mjs

@@ -203,6 +203,14 @@ export function encode(plaintext, key) {
     // Generate matrix representation of the plaintext.
     const plaintextMatrix = genMatrix(plaintext);
 
+    const det = determinant(keyMatrix, N);
+
+    if ((det % 2 === 0) || (det % 13 === 0))
+        throw new OperationError("Determinant has common factors with the modular base.");
+
+    if (det === 0)
+        throw new OperationError("Determinant is 0");
+
     return join(multiply(keyMatrix, plaintextMatrix));
 }
 

src/core/operations/HillCipherDecode.mjs

@@ -20,8 +20,8 @@ class HillCipherDecode extends Operation {
 
         this.name = "Hill Cipher Decode";
         this.module = "Crypto";
-        this.description = "";
-        this.infoURL = "";
+        this.description = "The Hill cipher is a polygraphic substitution cipher based on linear algebra. Invented by Lester S. Hill in 1929, it was the first polygraphic cipher in which it was practical (though barely) to operate on more than three symbols at once.";
+        this.infoURL = "https://wikipedia.org/wiki/Hill_cipher";
         this.inputType = "string";
         this.outputType = "string";
         this.args = [
@@ -39,7 +39,7 @@ class HillCipherDecode extends Operation {
      * @returns {string}
      */
     run(input, args) {
-        const key = args[0].toLowerCase();
+        let key = args[0].toLowerCase();
         input = input.toLowerCase();
         if (input.length === 0 || key.length === 0)
             return "";
@@ -47,6 +47,10 @@ class HillCipherDecode extends Operation {
         while (input.indexOf(" ") !== -1)
             input = input.replace(" ", "");
 
+        while (key.indexOf(" ") !== -1)
+            key = key.replace(" ", "");
+
+
         return HillCipher.decode(input, key);
     }
 

src/core/operations/HillCipherEncode.mjs

@@ -20,8 +20,8 @@ class HillCipherEncode extends Operation {
 
         this.name = "Hill Cipher Encode";
         this.module = "Crypto";
-        this.description = "";
-        this.infoURL = "";
+        this.description = "The Hill cipher is a polygraphic substitution cipher based on linear algebra. Invented by Lester S. Hill in 1929, it was the first polygraphic cipher in which it was practical (though barely) to operate on more than three symbols at once.";
+        this.infoURL = "https://wikipedia.org/wiki/Hill_cipher";
         this.inputType = "string";
         this.outputType = "string";
         this.args = [
@@ -40,7 +40,7 @@ class HillCipherEncode extends Operation {
      */
     run(input, args) {
 
-        const key = args[0].toLowerCase();
+        let key = args[0].toLowerCase();
         input = input.toLowerCase();
 
         // The algorithm has to have a non-empty input and a non-empty key.
@@ -51,6 +51,9 @@ class HillCipherEncode extends Operation {
         while (input.indexOf(" ") !== -1)
             input = input.replace(" ", "");
 
+        while (key.indexOf(" ") !== -1)
+            key = key.replace(" ", "");
+
         return HillCipher.encode(input, key);
     }
 

tests/operations/index.mjs

@@ -96,6 +96,7 @@ import "./tests/DefangIP.mjs";
 import "./tests/ParseUDP.mjs";
 import "./tests/AvroToJSON.mjs";
 import "./tests/Lorenz.mjs";
+import "./tests/HillCipher.mjs";
 
 
 // Cannot test operations that use the File type yet

tests/operations/tests/HillCipher.mjs

@@ -0,0 +1,47 @@
+/**
+ * HillCipher tests
+ *
+ * @author n1073645 [n1073645@gmail.com]
+ * @copyright Crown Copyright 2020
+ * @license Apache-2.0
+ */
+import TestRegister from "../../lib/TestRegister.mjs";
+
+TestRegister.addTests([
+    {
+        name: "Hill Cipher Encode",
+        input: "Hello World",
+        expectedOutput: "tutrquwdnv",
+        recipeConfig: [
+            { "op": "Hill Cipher Encode",
+                "args": ["Test"] }
+        ]
+    },
+    {
+        name: "Hill Cipher Decode",
+        input: "tutrquwdnv",
+        expectedOutput: "helloworld",
+        recipeConfig: [
+            { "op": "Hill Cipher Decode",
+                "args": ["Test"] }
+        ]
+    },
+    {
+        name: "Hill Cipher Bad Matrix",
+        input: "Hello World",
+        expectedOutput: "Determinant has common factors with the modular base.",
+        recipeConfig: [
+            { "op": "Hill Cipher Encode",
+                "args": ["th"] }
+        ]
+    },
+    {
+        name: "Hill Cipher Empty Key",
+        input: "Hello World",
+        expectedOutput: "",
+        recipeConfig: [
+            { "op": "Hill Cipher Encode",
+                "args": [""] }
+        ]
+    }
+]);