The Rust sshidentify can be used to gain information about the SSH key, that has been used for the current connection. The public get_ssh_info() will traverse through the process tree to find the parent sshd PID. Once found the PID is being used to check the systemd journal for the key fingerprint having been used for the connection. Last but not least the ~/.ssh/authorized_keys is being examined to find the public key for the fingerprint.

NOTE: The resulting binary must be called with permissions to access the system's systemd journal to be functional.

extern crate sshidentify;

/// Print information about first gpiochip
fn main() {
	let info = sshidentify::get_ssh_info().unwrap()
    println!("SSH Info: {:?}", info);
}

© 2018 Sebastian Reichel

ISC License

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.