Enigma Cipher

Advanced Enigma-style cipher engine with strong modern cryptography, fully stateless, ciphertext-only, supporting password, stealth, plugboard randomization, and MAC (message authentication code) integrity check. No meta/header required — everything is encoded in the ciphertext.

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Algorithm Details

• Rotor Machine: Uses three configurable rotors with custom wiring, position, notch, and ring setting logic inspired by the classical Enigma, but all rotor state is encoded in ciphertext (randomized each message unless using password/seed).
• Plugboard: Random or password-derived pairs provide extra permutation before/after the rotor chain (A-Z only).
• Reflector: Classic Enigma-style fixed mapping, creates a non-invertible chain for each pass.
• MAC Integrity: After all transformations, an HMAC-SHA256 is computed over ciphertext + encoded param to ensure tamper-proof security (using password or random salt as key).
• Base62 Encoding: All output is encoded using custom base62 to maximize density and printable output.
• Stealth Mode: If enabled, ciphertext is xored with random base62 pad, output is double-length and looks like random data.
• Self-Contained Param: All param (rotor position, plugboard, salt, order) is hidden inside the ciphertext, can be parsed back without any header/meta.

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Function/Flow

1. Encryption

   • Input is uppercased and swapped by the plugboard
   • Passed through 3 rotors (forward and backward), stepped on each char
   • Reflected
   • Reswapped by plugboard
   • Encoded to base62, length recorded
   • All settings (salt, plug, rotor position/order) obfuscated and encoded into ciphertext
   • MAC is computed over all relevant fields (no header)
   • In stealth mode: result is xored by random pad and output is double-length
   • Output: pure base62 string (no meta)

2. Decryption

   • If stealth: xor-pad decoding
   • Parse all settings from ciphertext (rotor, plug, salt, order)
   • Validate MAC over decoded fields (reject on mismatch)
   • Decode base62 to plaintext, plugboard swap
   • Reverse through rotors and plugboard
   • Output: fully reconstructed uppercase plaintext (A-Z and symbols)

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Code Comparison: Classic Enigma vs Enigma Cipher

Aspect	Classic Enigma	Enigma Cipher
Hardware	Electromechanical, fixed rotors	Pure software, stateless, random or passworded
Plugboard	Manual, fixed	Random or password-derived, encoded in ciphertext
Rotor Selection	Manual	Random/password, embedded and recoverable from cipher
Security	Weak by modern standards	Modern HMAC, brute-force resistant, password, MAC
Key/State Storage	Physical, operator memory	All state embedded and hidden in ciphertext
Output	Letters (A-Z) only	Letters/numbers, printable base62, supports symbols
Integrity	No built-in integrity	Tamper-proof, MAC checked before output
Mode/Replay	Deterministic by rotor start	Randomized each run (unless password/seed used)
Meta/Header	Not used, physical record	No header needed—ciphertext only, all param self-coded
Stealth	Not possible	Output xored with random pad for deniability

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Brute-Force Security Statistic

Attack Vector	Parameter	Value / Entropy
Plugboard	6 pairs, 12 letters	100+ billion combinations
Rotor Positions	26 × 26 × 26	17,576
Rotor Wiring Order	3!	6
Salt (random)	3 chars (base62)	238,328 possible salts
Password (user set)	8+ chars, strong	62^8 = 218 trillion+
Stealth Pad (if used)	N chars random	62^N (very high, per char)
HMAC Integrity	8 chars (base64)	2^48
Total Combined Entropy	Plug × Rotor × ...	>10^20 (if password strong)

• Brute-force attack is practically impossible with modern computing if a strong password is used.
• All security parameters are randomized and encoded for every message (unless seeded/password).

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Use Cases

1. Message Encryption (Stateless)

   node Enigma-Cipher.js encrypt 'Attack At Dawn'
   # Output: <base62-ciphertext>
   
   node Enigma-Cipher.js decrypt <base62-ciphertext>
   # Output: ATTACK AT DAWN

2. Password-Protected Secure Channel

   node Enigma-Cipher.js encrypt 'NeaByteLab Secret' --pass mySuperSecret
   # Output: <ciphertext>
   
   node Enigma-Cipher.js decrypt <ciphertext> --pass mySuperSecret
   # Output: NEABYTELAB SECRET

3. Stealth Mode For Obfuscated Messages

   node Enigma-Cipher.js encrypt 'Top Secret Order #123' --pass sniper --stealth
   # Output: <stealth base62>
   
   node Enigma-Cipher.js decrypt <stealth base62> --pass sniper --stealth
   # Output: TOP SECRET ORDER #123

4. Integrity Fail On Wrong Password

   node Enigma-Cipher.js decrypt <anycipher> --pass wrong
   # Output: FAILED: MAC integrity check failed!

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Research Use Guidance

• Fully open-source and transparent for cryptanalysis and academic study
• Modular design allows easy modification of rotors, plugboard, and MAC parameters
• Suitable for experiments on rotor-based ciphers combined with modern integrity checks
• Not intended for production commercial use without license compliance
• Cite NeaByteLab for any academic publication or presentation

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License

Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

• Free to use, modify, fork, study for any personal, academic, or open-source purpose
• Commercial use of any kind (selling, SaaS, company internal) is strictly prohibited
• Include credit to NeaByteLab if redistributed or published
• https://creativecommons.org/licenses/by-nc/4.0/