# capsicum
[](https://crates.io/crates/capsicum)
## Contain the awesome!
Rust bindings for the FreeBSD [capsicum](https://www.freebsd.org/cgi/man.cgi?query=capsicum)
framework for OS capability and sandboxing
## Prerequisites
[Rust](https://www.rust-lang.org/), [Cargo](https://crates.io/), and [FreeBSD](https://www.freebsd.org/).
**Note:** This currently only compiles on FreeBSD
## Getting Started
### Get the code
```
git clone https://github.com/danlrobertson/capsicum-rs
cd capsicum-rs
cargo build
```
### Writing code using `capsicum-rs`
#### Entering capability mode
```rust
use capsicum::{enter, sandboxed};
use std::fs::File;
use std::io::Read;
let mut ok_file = File::open("/tmp/foo").unwrap();
let mut s = String::new();
enter().expect("enter failed!");
assert!(sandboxed(), "application is not sandboxed!");
match File::create("/tmp/cant_touch_this") {
Ok(_) => panic!("application is not properly sandboxed!"),
Err(e) => println!("properly sandboxed: {:?}", e)
}
match ok_file.read_to_string(&mut s) {
Ok(_) => println!("This is okay since we opened the descriptor before sandboxing"),
Err(_) => panic!("application is not properly sandboxed!")
}
```
#### Limit capability rights to files
```rust
use capsicum::{CapRights, Right, RightsBuilder};
use std::fs::File;
use std::io::Read;
let x = rand::random::<bool>();
let mut ok_file = File::open("/tmp/foo").unwrap();
let mut s = String::new();
let mut builder = RightsBuilder::new(Right::Seek);
if x {
builder.add(Right::Read);
}
let rights = builder.finalize().unwrap();
rights.limit(&ok_file).unwrap();
match ok_file.read_to_string(&mut s) {
Ok(_) if x => println!("Allowed reading: x = {} ", x),
Err(_) if !x => println!("Did not allow reading: x = {}", x),
_ => panic!("Not properly sandboxed"),
}
```