Enx — Encryption Xcelerate

Caesar-shift cipher CLI written in pure C++.
Shifts every byte (raw mode) or every letter A–Z/a–z (alpha mode) by a user-supplied integer key.

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Build

git clone https://github.com/MRX-72/Enx
cd Enx
bash setup.sh

Requires g++ (GCC 9+) or clang++ (LLVM 10+).
On Windows, run setup.sh under Git Bash / WSL, or compile manually:

g++ EncDec.cpp -O2 -std=c++17 -o Enx.exe

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Syntax

Enx --str "<text>" --keyN <int> +E|+D [--alpha] [--hex] [--quiet]

Flag	Type	Description
--str "<text>"	string	Input text. Omit to read from stdin.
--keyN <int>	integer	Shift key (positive or negative).
+E	flag	Encrypt (default).
+D	flag	Decrypt.
--alpha	flag	Alpha-wrap mode: only A–Z / a–z shifted, wraps within alphabet.
--hex	flag	Print hex bytes of output alongside text.
--quiet	flag	Output result only — no banner, no labels. Useful for scripting.
--version	flag	Print version string.
--help	flag	Print usage.

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Examples

Basic encrypt / decrypt (raw shift)

# Encrypt
Enx --str "Hello World" --keyN 7 +E

# Decrypt
Enx --str "Olssv'^vrld" --keyN 7 +D

Alpha-wrap mode (ROT-N, printable-safe)

# Encrypt — only letters shift, spaces/punctuation unchanged
Enx --str "Hello, World!" --keyN 13 +E --alpha
# Output: Uryyb, Jbeyq!

# Decrypt
Enx --str "Uryyb, Jbeyq!" --keyN 13 +D --alpha
# Output: Hello, World!

Hex output

Enx --str "ABC" --keyN 1 +E --hex
# Output text : BCD
# Hex         : 42 43 44

Negative key

# Shift backwards — equivalent to decrypting with positive key
Enx --str "Hello" --keyN -3 +E

Stdin / pipe

echo "Secret Message" | Enx --keyN 5 +E

cat ciphertext.txt | Enx --keyN 5 +D --quiet > plaintext.txt

Quiet mode (scripting)

CIPHER=$(Enx --str "payload" --keyN 9 +E --quiet)
echo "Encrypted: $CIPHER"

Chaining encrypt then decrypt

Enx --str "Test" --keyN 42 +E --quiet | Enx --keyN 42 +D --quiet
# Output: Test

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Modes at a glance

Raw shift  (default)   — every byte += keyN
                         non-printable bytes possible at large keys

Alpha wrap (--alpha)   — only [A-Za-z] shifted
                         wraps within a-z / A-Z boundary
                         safe key: any integer (mod 26 applied internally)

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Key behaviour

keyN =  0    →  output == input  (warning shown)
keyN =  13   →  ROT13 when used with --alpha
keyN = -N +D →  same as keyN = +N +E

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Exit codes

Code	Meaning
0	Success
1	Bad arguments or missing input

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License

MIT — see LICENSE.