sudo

Detect if you are running as root, restart self with sudo if needed or setup uid zero when running with the SUID flag set.

Requirements

• The sudo program is required to be installed and setup correctly on the target system.
• Linux or Mac OS X tested
  • It should work on *BSD. However, it is not tested.

Example:

First, add sudo to your Cargo.toml:

yaml [dependencies] sudo = "0.6"

In your main.rs:

rust fn main() -> Result<(), Box<dyn Error>> { sudo::escalate_if_needed()?; println!("Hello, Root-World!"); Ok( () ) }

If you are using logging based on the log infrastructure you will get timestamped and formatted output.

Passing RUST_BACKTRACE

The crate will automatically keep the setting of RUST_BACKTRACE intact if it is set to one of the following values:

• `` <- empty string means no pass-through
• 1 or true <- standard trace
• full <- full trace

bash $ RUST_BACKTRACE=full cargo run --example backtrace 2020-07-05 18:10:31,544 TRACE [sudo] Running as User 2020-07-05 18:10:31,544 DEBUG [sudo] Escalating privileges 2020-07-05 18:10:31,544 TRACE [sudo] relaying RUST_BACKTRACE=full [sudo] Passwort für user: 2020-07-05 18:10:39,238 TRACE [sudo] Running as Root 2020-07-05 18:10:39,238 TRACE [sudo] already running as Root 2020-07-05 18:10:39,238 INFO [backtrace] entering failing_function thread 'main' panicked at 'now you see me fail', examples/backtrace.rs:16:5

Keeping part of the environment

You can keep parts of your environment across the sudo barrier. This enables more configuration options often used in daemons or cloud environments:

rust // keeping all environment variables starting with "EXAMPLE_" or "CARGO" sudo::with_env(&["EXAMPLE_", "CARGO"]).expect("sudo failed");

Warning: This may introduce security problems to your application if untrusted users are able to set these variables.

``bash $ EXAMPLE_EXEC='$(ls)' EXAMPLE_BTICKS='ls`' cargo run --example environment 2020-07-07 16:32:11,261 INFO [environment] ① uid: 1000; euid: 1000;

...

declare -x EXAMPLEBTICKS="`ls`" declare -x EXAMPLEEXEC="\$(ls)" ...

[sudo] password for user:

2020-07-07 16:32:11,285 TRACE [sudo] Running as Root 2020-07-07 16:32:11,285 TRACE [sudo] already running as Root 2020-07-07 16:32:11,285 INFO [environment] ② uid: 0; euid: 0;

...

declare -x EXAMPLEBTICKS="`ls`" declare -x EXAMPLEEXEC="\$(ls)" ```

Run a program with SUID

```bash $ cargo run --example suid 2020-04-17 15:13:49,450 INFO [suid] ① uid: 1000; euid: 1000; uid=1000(user) gid=1000(user) groups=1000(user),4(adm),27(sudo) 2020-04-17 15:13:49,453 TRACE [sudo] Running as User 2020-04-17 15:13:49,453 DEBUG [sudo] Escalating privileges [sudo] password for user: 2020-04-17 15:13:53,529 INFO [suid] ① uid: 0; euid: 0; uid=0(root) gid=0(root) groups=0(root) 2020-04-17 15:13:53,532 TRACE [sudo] Running as Root 2020-04-17 15:13:53,532 TRACE [sudo] already running as Root 2020-04-17 15:13:53,532 INFO [suid] ② uid: 0; euid: 0; uid=0(root) gid=0(root) groups=0(root)

```

Then give the file to root and add the suid flag.

bash $ sudo chown root target/debug/examples/suid $ sudo chmod 4755 target/debug/examples/suid

Now run the program again:

bash $ target/debug/examples/suid 2020-04-17 15:14:37,199 INFO [suid] ① uid: 1000; euid: 0; uid=1000(user) gid=1000(user) euid=0(root) groups=1000(user),4(adm),27(sudo) 2020-04-17 15:14:37,202 TRACE [sudo] Running as Suid 2020-04-17 15:14:37,202 TRACE [sudo] setuid(0) 2020-04-17 15:14:37,202 INFO [suid] ② uid: 0; euid: 0; uid=0(root) gid=1000(user) groups=1000(user),4(adm),27(sudo)