Secure File Locker (C++)

A command-line tool to encrypt/decrypt files using AES-256-GCM with PBKDF2-HMAC-SHA256 key derivation, plus metadata, verify, list, and secure delete.

Features

• AES-256-GCM authenticated encryption
• PBKDF2-HMAC-SHA256 (configurable iterations)
• Per-file random salt (16B) and IV/nonce (12B)
• Embedded metadata: original filename, size, plaintext SHA-256
• Streaming I/O for large files
• Best-effort secure delete (overwrite, fsync, unlink)
• Simple CLI: encrypt, decrypt, verify, list, delete-secure

Build (macOS via Homebrew, Linux similar)

# prerequisites
xcode-select --install || true
brew install cmake openssl@3

# configure & build
OPENSSL_PREFIX="$(brew --prefix openssl@3)"
cmake -S . -B build -DCMAKE_BUILD_TYPE=Release   -DOPENSSL_ROOT_DIR="$OPENSSL_PREFIX"   -DOPENSSL_INCLUDE_DIR="$OPENSSL_PREFIX/include"   -DOPENSSL_CRYPTO_LIBRARY="$OPENSSL_PREFIX/lib/libcrypto.dylib"
cmake --build build --config Release

Usage

./build/sflk --help
./build/sflk encrypt <file> [--iter N] [--out file.sflk]
./build/sflk decrypt <file.sflk> [--out restored_name]
./build/sflk verify  <file.sflk>
./build/sflk list    <file.sflk>
./build/sflk delete-secure <file>