# Emet (אמת)
> **"Mathematics does not lie. Truth is immutable."**
**Emet** (Hebrew for *Truth*) is a command-line tool built in **Rust** designed to guarantee the integrity and authorship of digital files. Whether sealing the source code of a critical system or the chapters of an epic 23-volume saga (for example), Emet creates a mathematical proof that a specific content existed at a specific time and was signed by you.
At its core, Emet utilizes **Tequel v1.1.0**, a custom low-level hashing library, ensuring that even a single-bit alteration is detected.
---
## 🚀 Features (v1.0.0)
* **Seal:** Generates a digital "fingerprint" of the file by combining the content, a UTC timestamp, and your private key.
* **Audit:** Verifies if the current file matches the original seal through the `check` command.
* **Double-Check Security:** Validates both **Integrity** (has the physical file changed?) and **Authenticity** (does the signature belong to the true author?).
* **Transparent Persistence:** Generates `.emet` files in JSON format, allowing for human auditing and easy archiving.
---
## 🛠️ The Workflow of Truth
The sealing and verification process follows a rigorous cryptographic pipeline:
1. **Hashing:** Emet reads the file bytes and uses the **Tequel** algorithm to generate a high-entropy hash.
2. **Signing:** The hash is concatenated with the *timestamp* and your `private_key`. The result of this mix is hashed again to create the `digital_signature`.
3. **Verification:** When running `check`, Emet reconstructs the signature with current data. If a single character in the original file or the date in the seal is modified, the "Truth is Violated."
---
## Installation
Install CLI (bin):
```bh
cargo install emet
```
Instal with Dependencie (API):
```toml
[dependencies]
emet = "1.0.0"
```
or
```bh
cargo add emet
```
## 💻 Usage Example
In your `main.rs`:
```rust
// Instance Emet
let mut emet = Emet::up("private_key");
// Sealing a file
let sealed = emet.seal("chapter_01.md")?;
emet.save_seal("chapter_01.md", &sealed)?;
// Verifying integrity
match emet.check("chapter_01.md", "chapter_01.md.emet") {
Ok(_) => println!("✅ Good! The truth remains intact."),
Err(e) => eprintln!("❌ Error: {}", e), // e.g., Truth Violated
}
```
or via CLI:
```bh
emet up my_private_key
emet seal ./myfile.txt
emet check ./myfile.txt ./myfile.txt.emet
```
## 🧬 Tecnnical Specifications
- Language: Rust (2024 Edition)
- Hashing Engine: [Tequel v1.1.0](https://crates.io/crates/tequel-rs) (7.999885 bits/byte entropy)
- Seal Format: JSON (via `Serde`)
- Time Standard: UTC RCF3339 (via `Chrono`)
## 📜 Philosophy
Emet is not just a checksum utility; it is a personal digital notary. It was built to protect the vision of creators who understand that while the future may be uncertain, the past and authorship must be incontestable.
**Developed by Gabriel "dotxav" Xavier.** *If the truch can be corrupted, it is not the truth.*
## 📄 License
Licensed under the MIT License. Free to use, modify, and distribute.