# `encrypted-message`
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Safely encrypt & store serializable data using AES-256-GCM.

## Install

```toml
[dependencies]
encrypted-message = "0.3"
```

## Integration with Diesel

`EncryptedMessage` implements [`FromSql`][diesel-fromsql] & [`ToSql`][diesel-tosql], allowing you to use `EncryptedMessage` as a field type in your models.

- **MySQL**: Enable the `diesel` & `diesel-mysql` features. Supports the [`Json`][diesel-json] type.
- **PostgreSQL**: Enable the `diesel` & `diesel-postgres` features. Supports the [`Json`][diesel-json] & [`Jsonb`][diesel-jsonb] types.

```toml
[dependencies]
encrypted-message = { version = "0.3", features = ["diesel", "diesel-<mysql|postgres>"] }
```

## Examples

- [`examples/basic.rs`](./examples/basic.rs), a basic example of how to use `encrypted-message`.
- [`examples/config_with_external_data.rs`](./examples/config_with_external_data.rs), an example of a `Config` that depends on external data, like a user-provided key or password.

## Security

This crate uses trusted, pure-Rust encryption using the [`aes_gcm`](https://crates.io/crates/aes_gcm) crate
from the [Rust Crypto][rust-crypto] organization.

Keys are handled safely using the [`secrecy`](https://crates.io/crates/secrecy) crate,
which internally uses the [`zeroize`](https://crates.io/crates/zeroize) crate (also from [Rust Crypto][rust-crypto])
to zero-out the keys in memory when no longer used.

[diesel-fromsql]: https://docs.diesel.rs/2.1.x/diesel/deserialize/trait.FromSql.html
[diesel-tosql]: https://docs.diesel.rs/2.1.x/diesel/serialize/trait.ToSql.html
[diesel-json]: https://docs.diesel.rs/2.1.x/diesel/sql_types/struct.Json.html
[diesel-jsonb]: https://docs.diesel.rs/2.1.x/diesel/sql_types/struct.Jsonb.html

[rust-crypto]: https://github.com/RustCrypto