happy-cracking

A fast, comprehensive CTF (Capture The Flag) toolkit written in Rust. Provides 30+ command-line utilities for cryptographic encoding/decoding, classic ciphers, hash operations, and analysis tools commonly used in security competitions.

Installation

git clone https://github.com/riya-amemiya/happy-cracking.git
cd happy-cracking
cargo build --release

The binary will be available at target/release/happy-cracking.

Features

Encoding (11 tools)

Command	Description
`base64`	Base64 encode/decode
`base32`	Base32 encode/decode
`base58`	Base58 encode/decode (Bitcoin-style)
`base85`	Base85 (ASCII85) encode/decode
`base91`	Base91 encode/decode
`hex`	Hexadecimal encode/decode
`url`	URL percent-encoding encode/decode
`binary`	Binary (8-bit) encode/decode
`morse`	Morse code encode/decode
`a1z26`	A=1, B=2, ..., Z=26 number-letter conversion
`numconv`	Number base conversion (bases 2-36)

Classic Ciphers (12 tools)

Command	Description
`rot13`	ROT13 cipher
`rot47`	ROT47 cipher (ASCII 33-126 range)
`caesar`	Caesar cipher with encrypt/decrypt/bruteforce
`vigenere`	Vigenere polyalphabetic cipher
`beaufort`	Beaufort cipher (self-reciprocal Vigenere variant)
`atbash`	Atbash cipher (A↔Z substitution)
`affine`	Affine cipher (ax+b mod 26)
`railfence`	Rail Fence transposition cipher
`playfair`	Playfair cipher (5x5 digraph substitution)
`columnar`	Columnar transposition cipher
`baconian`	Baconian cipher (5-bit A/B steganographic encoding)
`polybius`	Polybius square cipher
`xor`	XOR cipher with single-byte bruteforce

Hash Operations (2 tools)

Command	Description
`hash`	Generate MD5, SHA1, SHA256, SHA512 hashes
`hashid`	Identify hash type from a hash string

Utilities (7 tools)

Command	Description
`auto`	Auto-detect and decode common encodings
`chain`	Chain multiple operations together (CyberChef-style)
`entropy`	Shannon entropy analysis
`frequency`	Character frequency analysis
`math`	Number theory tools (GCD, LCM, modular inverse, modular exponentiation)
`primes`	Prime factorization and primality test
`str`	String tools (reverse, ord, chr)

Usage

Encoding

# Base64
happy-cracking base64 encode "Hello, World!"
happy-cracking base64 decode "SGVsbG8sIFdvcmxkIQ=="

# Base85 (ASCII85)
happy-cracking base85 encode "Hello"
happy-cracking base85 decode "87cURDZ"

# A1Z26
happy-cracking a1z26 encode "HELLO"        # 8-5-12-12-15
happy-cracking a1z26 decode "8-5-12-12-15"  # HELLO

# Number base conversion
happy-cracking numconv convert 255 --from 10 --to 16   # ff
happy-cracking numconv convert ff --from 16 --to 2      # 11111111

Classic Ciphers

# Caesar cipher
happy-cracking caesar encrypt "Hello" --shift 3
happy-cracking caesar bruteforce "Khoor"

# Vigenere cipher
happy-cracking vigenere encrypt "HELLO" --key "KEY"
happy-cracking vigenere decrypt "RIJVS" --key "KEY"

# Playfair cipher
happy-cracking playfair encrypt "HELLO WORLD" --key "MONARCHY"

# Columnar transposition
happy-cracking columnar encrypt "HELLO WORLD" --key "ZEBRA"

# ROT47 (numbers and symbols too)
happy-cracking rot47 "Hello, World! 123"

Hash Operations

happy-cracking hash sha256 "password"
happy-cracking hashid identify "5d41402abc4b2a76b9719d911017c592"

Utilities

# Shannon entropy analysis
happy-cracking entropy analyze "Hello World"

# Number theory
happy-cracking math gcd 12345 67890
happy-cracking math modinv 3 26        # Modular inverse
happy-cracking math modpow 2 10 1000   # Modular exponentiation

# Prime factorization
happy-cracking primes factorize 84      # 2^2 × 3 × 7
happy-cracking primes isprime 104729

# String tools
happy-cracking str reverse "flag{hello}"
happy-cracking str ord "ABC"                    # A=65 B=66 C=67
happy-cracking str chr "72 101 108 108 111"     # Hello

# Chain operations (CyberChef-style pipeline)
happy-cracking chain run "Hello" --ops "base64-encode"
happy-cracking chain run "SGVsbG8=" --ops "base64-decode,rot13"
happy-cracking chain run "Hello" --ops "upper,hex-encode"

The chain command supports the following operations: base64-encode, base64-decode, base32-encode, base32-decode, hex-encode, hex-decode, url-encode, url-decode, binary-encode, binary-decode, rot13, rot47, reverse, upper, lower.

Development

cargo build            # Build
cargo test             # Run all tests (265 tests)
cargo fmt              # Format code
cargo clippy -- -D warnings  # Lint

License

This project is for educational and CTF competition purposes.

happy-cracking 0.1.0