AuraVPN/crates/aura-cli/tests/pki_roundtrip.rs

//! PKI roundtrip: drive the `aura pki` handlers to init a CA, issue server + client certs, then
//! verify each against [`aura_pki::AuraCertVerifier`]. A cert from a *different* CA must fail.
//!
//! Runs without root or network: everything is file I/O into a unique temp directory.

use std::path::PathBuf;

use aura_cli::pki;
use aura_pki::{AuraCa, AuraCertVerifier};
use rustls_pki_types::CertificateDer;

/// A unique temp directory for this test process (no `tempfile` dependency in the workspace).
fn temp_dir(tag: &str) -> PathBuf {
    let mut dir = std::env::temp_dir();
    dir.push(format!(
        "aura-cli-test-{tag}-{}-{}",
        std::process::id(),
        std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)
            .unwrap()
            .as_nanos()
    ));
    std::fs::create_dir_all(&dir).expect("create temp dir");
    dir
}

/// Decode a single-certificate PEM string into a DER chain for the verifier.
fn pem_chain(pem: &str) -> Vec<CertificateDer<'static>> {
    let (_, parsed) = x509_parser::pem::parse_x509_pem(pem.as_bytes()).expect("parse PEM");
    vec![CertificateDer::from(parsed.contents)]
}

#[test]
fn ca_init_issue_and_verify_roundtrip() {
    let dir = temp_dir("pki");

    // init the CA.
    let (ca_cert_path, ca_key_path) = pki::init("Aura Roundtrip CA", &dir).expect("pki init");
    assert!(ca_cert_path.exists() && ca_key_path.exists());
    assert_eq!(ca_cert_path.file_name().unwrap(), "ca.crt");

    // issue server + client certs (CA dir defaults to the same dir).
    let (server_crt, server_key) =
        pki::issue_server("vpn.example.com", &dir, &dir).expect("issue server");
    let (client_crt, client_key) =
        pki::issue_client("client-42", &dir, &dir).expect("issue client");
    assert!(server_crt.exists() && server_key.exists());
    assert!(client_crt.exists() && client_key.exists());

    // Load the CA back and build a verifier from its PEM.
    let ca = AuraCa::load(&ca_cert_path, &ca_key_path).expect("load CA");
    let verifier = AuraCertVerifier::new(&ca.ca_cert_pem()).expect("verifier");

    // Verify the server cert for its SAN.
    let server_pem = std::fs::read_to_string(&server_crt).unwrap();
    verifier
        .verify_server_cert(&pem_chain(&server_pem), "vpn.example.com")
        .expect("server cert verifies for its SAN");

    // Wrong name must fail.
    assert!(verifier
        .verify_server_cert(&pem_chain(&server_pem), "wrong.example.com")
        .is_err());

    // Verify the client cert; the returned CN must be the issued id.
    let client_pem = std::fs::read_to_string(&client_crt).unwrap();
    let cn = verifier
        .verify_client_cert(&pem_chain(&client_pem))
        .expect("client cert verifies");
    assert_eq!(cn, "client-42");

    // A certificate from a *different* CA must NOT verify against this CA.
    let other_dir = temp_dir("pki-other");
    pki::init("Other CA", &other_dir).expect("other CA");
    let (other_client, _k) =
        pki::issue_client("intruder", &other_dir, &other_dir).expect("other client");
    let other_pem = std::fs::read_to_string(&other_client).unwrap();
    assert!(
        verifier.verify_client_cert(&pem_chain(&other_pem)).is_err(),
        "a cert from a different CA must fail verification"
    );

    // Cleanup (best effort).
    let _ = std::fs::remove_dir_all(&dir);
    let _ = std::fs::remove_dir_all(&other_dir);
}

#[test]
fn revoke_then_list() {
    let dir = temp_dir("crl");
    let crl = dir.join("revoked.crl");

    // Empty / absent CRL lists nothing.
    assert!(pki::list(&crl).unwrap().is_empty());

    pki::revoke("client-42", &crl).expect("revoke 1");
    pki::revoke("deadbeef", &crl).expect("revoke 2");
    // Re-revoking is idempotent (set semantics).
    pki::revoke("client-42", &crl).expect("revoke dup");

    let mut listed = pki::list(&crl).expect("list");
    listed.sort();
    assert_eq!(
        listed,
        vec!["client-42".to_string(), "deadbeef".to_string()]
    );

    let _ = std::fs::remove_dir_all(&dir);
}