Diff: Enigma.cpp

Revision:

2:ee55abc2b6a2

Parent:

1:a21920e248d3

Child:

3:9590c44c9ecd

diff -r a21920e248d3 -r ee55abc2b6a2 Enigma.cpp
--- a/Enigma.cpp	Mon Sep 23 07:50:09 2019 +0000
+++ b/Enigma.cpp	Tue Sep 24 08:52:11 2019 +0000
@@ -121,6 +121,7 @@
 /**
  * @brief   Constructor
  * @note    Selects which rotors are going to be used and sets their intial position.
+ * @note    Also connects pairs of plugs on the plugboard with cords.
  * @param
  * @retval
  */
@@ -131,12 +132,15 @@
     const uint8_t*  rightRotorSel,
     uint8_t         leftRotorPos,
     uint8_t         middleRotorPos,
-    uint8_t         rightRotorPos
+    uint8_t         rightRotorPos,
+    uint8_t         (*plugboard)[2],
+    uint8_t         cords
 ) :
     _len(256),
     _leftRotorPos(leftRotorPos),
     _middleRotorPos(middleRotorPos),
-    _rightRotorPos(rightRotorPos)
+    _rightRotorPos(rightRotorPos),
+    _cords(cords)
 {
     // Initialize entry wheel.
     for (size_t i = 0; i < _len; i++) {
@@ -150,17 +154,26 @@
 
     // Initialize reflector.
     _reflector = const_cast<uint8_t*>(REFLECTOR);
+
+    _plugboard = new uint8_t[cords][2];
+    for (size_t i = 0; i < cords; i++) {
+        for (size_t j = 0; j < 2; j++) {
+            _plugboard[i][j] = plugboard[i][j];
+        }
+    }
 }
 
 /**
  * @brief   Encrypts a byte array.
- * @note    Encryption capability is extended from 26 chars to all 256 bytes.
+ * @note    Encryption capability is extended from 26 upper case letters to any byte.
  * @retval  out Pointer to a byte array to store the encrypted bytes in.
  * @param   in  Pointer to a byte array to be encrypted.
  * @param   len Length of the byte array.
  */
 uint8_t* Enigma::encrypt(uint8_t* out, const uint8_t* in, size_t len)
 {
+    bool found;
+
     // Sets initial permutation
     int leftRotorPos = _leftRotorPos;
     int middleRotorPos = _middleRotorPos;
@@ -169,6 +182,21 @@
     for (size_t i = 0; i < len; i++) {
         uint8_t byte = in[i];
 
+        // Swap bytes connected with cords
+        found = false;
+        for (size_t j = 0; j < _cords; j++) {
+            for (size_t k = 0; k < 2; k++) {
+                if (_plugboard[j][k] == byte) {
+                    byte = k == 0 ? _plugboard[j][1] : _plugboard[j][0];
+                    found = true;
+                    break;
+                }
+            }
+            if (found) {
+                break;
+            }
+        }
+
         // Advance right rotor on every byte entry
         rightRotorPos = _mod(rightRotorPos + 1);
 
@@ -177,8 +205,8 @@
             middleRotorPos = _mod(middleRotorPos + 2);
         }
 
-        // Advance left rotor using a notch located at position #13
-        if ((middleRotorPos % 13) == 0) {
+        // Advance left rotor using a notch located at position #201
+        if ((middleRotorPos % 201) == 0) {
             leftRotorPos = _mod(leftRotorPos + 1);
         }
 
@@ -196,6 +224,21 @@
         byte = _entryWheel[_mod(_find(byte, _middleRotor) - middleRotorPos + rightRotorPos)];
         byte = _entryWheel[_mod(_find(byte, _rightRotor) - rightRotorPos)];
 
+        // Swap bytes connected with cords
+        found = false;
+        for (size_t j = 0; j < _cords; j++) {
+            for (size_t k = 0; k < 2; k++) {
+                if (_plugboard[j][k] == byte) {
+                    byte = k == 0 ? _plugboard[j][1] : _plugboard[j][0];
+                    found = true;
+                    break;
+                }
+            }
+            if (found) {
+                break;
+            }
+        }
+
         out[i] = byte;
     }