🔐 HashGuardian — Text Integrity Checker

Detect whether text has been modified using cryptographic hashing.

HashGuardian lets you snapshot any text, then verify it later to detect even the tiniest change — a single character, an extra space, or a full rewrite.

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✨ Features

• ✅ Hash any text using MD5, SHA-1, SHA-256, or SHA-512
• 📸 Save snapshots of text with a label to a local vault
• 🔍 Verify text against saved snapshots to detect tampering
• ↔️ Compare two texts directly (no snapshot needed)
• 📋 List and delete saved snapshots
• 🎨 Beautiful terminal output with color-coded results
• 🧪 Fully tested with pytest (30+ tests)

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📁 Project Structure

hash_guardian/
├── hasher.py        # Core hashing logic (library)
├── cli.py           # CLI interface
├── test_hasher.py   # Unit tests (pytest)
├── requirements.txt
└── README.md

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🚀 Getting Started

git clone https://github.com/master-coder1998/HashGuardian-Text-Integrity-Checker.git
cd HashGuardian
pip install -r requirements.txt

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💻 CLI Usage

Hash text

python cli.py hash "Hello, World!"
python cli.py hash "Hello, World!" --all        # show all algorithms
python cli.py hash "Hello" -a md5               # use MD5

Save a snapshot

python cli.py save my_doc "This is the original text."
python cli.py save contract "Terms and conditions..." -a sha512

Verify text against snapshot

python cli.py verify my_doc "This is the original text."
# ✔ INTACT — Text has NOT been modified.

python cli.py verify my_doc "This is the modified text."
# ✘ MODIFIED — Text has been tampered with!

Compare two texts directly

python cli.py compare --file1 original.txt --file2 received.txt

Manage snapshots

python cli.py list              # show all snapshots
python cli.py delete my_doc     # delete a snapshot

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🐍 Use as a Library

from hasher import compute_hash, save_hash, verify_text, compare_texts

# Compute a hash
h = compute_hash("Hello World", algorithm="sha256")

# Save a snapshot
save_hash("my_label", "Original text here")

# Verify later
result = verify_text("my_label", "Original text here")
print(result["status"])   # "INTACT" or "MODIFIED"

# Compare two texts
result = compare_texts("text one", "text two")
print(result["identical"])  # False

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🧪 Running Tests

pip install pytest
pytest test_hasher.py -v

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🔬 How It Works

1. Hashing — Text is encoded to UTF-8 bytes and passed through a hash function (SHA-256 by default). This produces a fixed-length fingerprint unique to the content.
2. Vault — Snapshots are stored in a local hash_vault.json file with the label, hash, algorithm, length, and timestamp.
3. Verification — When verifying, the current text is re-hashed with the same algorithm and compared to the stored hash. Any change — even a single space — produces a completely different hash.

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📦 Supported Algorithms

Algorithm	Output Length	Notes
MD5	32 hex chars	Fast, not collision-resistant
SHA-1	40 hex chars	Deprecated for security use
SHA-256	64 hex chars	✅ Recommended default
SHA-512	128 hex chars	Highest security

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👤 Author

master-coder1998

• GitHub: @master-coder1998

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📄 License

MIT License — free to use and modify.