d-OAuth-Client/crates/provision/tests/keygen.rs

//! `provision keygen` contract: fresh P-256 key, `0600` file, stable
//! thumbprint, and no silent overwrite of an in-use key.

use std::path::PathBuf;

use provision::keygen::{DEFAULT_DPOP_KEY_PATH, generate_key};

fn unique_dir(tag: &str) -> PathBuf {
  let dir = std::env::temp_dir().join(format!("provision-keygen-{}-{tag}", std::process::id()));
  std::fs::create_dir_all(&dir).expect("test tempdir must be creatable");
  dir
}

#[test]
fn keygen_writes_0600_reloads_with_stable_thumbprint() {
  let dir = unique_dir("roundtrip");
  let path = dir.join("dpop-key.json");

  let first_jkt = generate_key(&path, false).expect("first keygen must succeed");
  assert!(path.exists(), "key file must exist after keygen");

  let loaded =
    oauth_core::dpop::key::DpopKey::load_from_file(&path).expect("generated file must reload");
  assert_eq!(loaded.thumbprint().expect("thumbprint"), first_jkt);

  let raw = std::fs::read_to_string(&path).expect("key file must be readable");
  let value: serde_json::Value = serde_json::from_str(&raw).expect("key file must be JSON");
  assert_eq!(value.get("kty").and_then(|v| v.as_str()), Some("EC"));
  assert!(value.get("d").is_some(), "persisted JWK carries the scalar");

  #[cfg(unix)]
  {
    use std::os::unix::fs::PermissionsExt;
    let mode = std::fs::metadata(&path)
      .expect("metadata")
      .permissions()
      .mode()
      & 0o777;
    assert_eq!(mode, 0o600, "DPoP key file must be owner-only");
  }

  std::fs::remove_file(&path).expect("cleanup");
  std::fs::remove_dir(&dir).expect("cleanup");
}

#[test]
fn keygen_refuses_overwrite_without_force_and_rotates_with_force() {
  let dir = unique_dir("overwrite");
  let path = dir.join("dpop-key.json");

  let first_jkt = generate_key(&path, false).expect("first keygen must succeed");
  let before = std::fs::read(&path).expect("key file must be readable");

  let err = generate_key(&path, false).expect_err("second keygen must fail");
  assert!(
    matches!(err, provision::keygen::KeygenError::Exists { .. }),
    "rerun without --force must be a typed Exists error"
  );
  let kept = std::fs::read(&path).expect("key file must still be readable");
  assert_eq!(kept, before, "refused rerun must leave the key untouched");

  let second_jkt = generate_key(&path, true).expect("--force must rotate");
  assert_ne!(first_jkt, second_jkt, "forced rerun must mint a fresh key");
  let rotated =
    oauth_core::dpop::key::DpopKey::load_from_file(&path).expect("rotated file must reload");
  assert_eq!(rotated.thumbprint().expect("thumbprint"), second_jkt);

  std::fs::remove_file(&path).expect("cleanup");
  std::fs::remove_dir(&dir).expect("cleanup");
}

#[test]
fn default_dpop_key_path_matches_server_convention() {
  assert_eq!(DEFAULT_DPOP_KEY_PATH, "config/dpop-key.json");
}