libnss-rs
Rust bindings for creating libnss modules.
Currently supports the following databases:
- passwd
- shadow
- group
- hosts
Getting started
- Create a new library
cargo new nss_example --lib- Change library type to
cdylibin yourCargo.toml
[lib]
name = "nss_example"
crate-type = [ "cdylib" ]*** NOTE *** The name of the crate itself is not important, however the library itself must follow the nss_xxx pattern.
- Add
libnssto yourCargo.toml
[dependencies]
libc = "0.2.0"
lazy_static = "1.3.0"
paste = "0.1"
libnss = "0.1.0"- Add the following to your
src/main.rs
extern crate libc;
#[macro_use]
extern crate lazy_static;
#[macro_use]
extern crate libnss;- Implement a
passwddatabase
use libnss::passwd::{PasswdHooks, Passwd};
struct ExamplePasswd;
libnss_passwd_hooks!(example, ExamplePasswd);It is important that the first param of libnss_passwd_hooks is the name of your final library libnss_example.so.2
impl PasswdHooks for HardcodedPasswd {
fn get_all_entries() -> Vec<Passwd> {
vec![
Passwd {
name: "test".to_string(),
passwd: "x".to_string(),
uid: 1005,
gid: 1005,
gecos: "Test Account".to_string(),
dir: "/home/test".to_string(),
shell: "/bin/bash".to_string(),
}
]
}
fn get_entry_by_uid(uid: libc::uid_t) -> Option<Passwd> {
if uid == 1005 {
return Some(Passwd {
name: "test".to_string(),
passwd: "x".to_string(),
uid: 1005,
gid: 1005,
gecos: "Test Account".to_string(),
dir: "/home/test".to_string(),
shell: "/bin/bash".to_string(),
});
}
None
}
fn get_entry_by_name(name: String) -> Option<Passwd> {
if name == "test" {
return Some(Passwd {
name: "test".to_string(),
passwd: "x".to_string(),
uid: 1005,
gid: 1005,
gecos: "Test Account".to_string(),
dir: "/home/test".to_string(),
shell: "/bin/bash".to_string(),
});
}
None
}
}- Install the library
cd target/release
cp libnss_example.so libnss_example.so.2
sudo install -m 0644 libnss_example.so.2 /lib
sudo /sbin/ldconfig -n /lib /usr/lib- Enable your nss module in
/etc/nsswitch.conf
eg:
passwd: example files systemd
The name in here must follow the final library name libnss_example.so.2
- Look at the examples for more information
