1use std::{
2 path::{Path, PathBuf},
3 process::Command,
4 sync::Arc,
5};
6
7use chrono::{DateTime, Duration, Utc};
8use futures::future::BoxFuture;
9use http::{
10 header::{InvalidHeaderValue, AUTHORIZATION},
11 HeaderValue, Request,
12};
13use jsonpath_rust::JsonPath;
14use secrecy::{ExposeSecret, SecretString};
15use serde::{Deserialize, Serialize};
16use thiserror::Error;
17use tokio::sync::{Mutex, RwLock};
18use tower::{filter::AsyncPredicate, BoxError};
19
20use crate::config::{AuthInfo, AuthProviderConfig, ExecAuthCluster, ExecConfig, ExecInteractiveMode};
21
22#[cfg(feature = "oauth")] mod oauth;
23#[cfg(feature = "oauth")] pub use oauth::Error as OAuthError;
24#[cfg(feature = "oidc")] mod oidc;
25#[cfg(feature = "oidc")] pub use oidc::errors as oidc_errors;
26#[cfg(target_os = "windows")] use std::os::windows::process::CommandExt;
27
28#[derive(Error, Debug)]
29pub enum Error {
31 #[error("invalid basic auth: {0}")]
33 InvalidBasicAuth(#[source] InvalidHeaderValue),
34
35 #[error("invalid bearer token: {0}")]
37 InvalidBearerToken(#[source] InvalidHeaderValue),
38
39 #[error("tried to refresh a token and got a non-refreshable token response")]
41 UnrefreshableTokenResponse,
42
43 #[error("exec-plugin response did not contain a status")]
45 ExecPluginFailed,
46
47 #[error("malformed token expiration date: {0}")]
49 MalformedTokenExpirationDate(#[source] chrono::ParseError),
50
51 #[error("unable to run auth exec: {0}")]
53 AuthExecStart(#[source] std::io::Error),
54
55 #[error("auth exec command '{cmd}' failed with status {status}: {out:?}")]
57 AuthExecRun {
58 cmd: String,
60 status: std::process::ExitStatus,
62 out: std::process::Output,
64 },
65
66 #[error("failed to parse auth exec output: {0}")]
68 AuthExecParse(#[source] serde_json::Error),
69
70 #[error("failed to serialize input: {0}")]
72 AuthExecSerialize(#[source] serde_json::Error),
73
74 #[error("failed exec auth: {0}")]
76 AuthExec(String),
77
78 #[error("failed to read token file '{1:?}': {0}")]
80 ReadTokenFile(#[source] std::io::Error, PathBuf),
81
82 #[error("failed to parse token-key")]
84 ParseTokenKey(#[source] serde_json::Error),
85
86 #[error("command must be specified to use exec authentication plugin")]
88 MissingCommand,
89
90 #[cfg(feature = "oauth")]
92 #[cfg_attr(docsrs, doc(cfg(feature = "oauth")))]
93 #[error("failed OAuth: {0}")]
94 OAuth(#[source] OAuthError),
95
96 #[cfg(feature = "oidc")]
98 #[cfg_attr(docsrs, doc(cfg(feature = "oidc")))]
99 #[error("failed OIDC: {0}")]
100 Oidc(#[source] oidc_errors::Error),
101
102 #[error("Cluster spec must be populated when `provideClusterInfo` is true")]
104 ExecMissingClusterInfo,
105
106 #[error("No valid native root CA certificates found")]
108 NoValidNativeRootCA(#[source] std::io::Error),
109}
110
111#[derive(Debug, Clone)]
112#[allow(clippy::large_enum_variant)]
113pub(crate) enum Auth {
114 None,
115 Basic(String, SecretString),
116 Bearer(SecretString),
117 RefreshableToken(RefreshableToken),
118 Certificate(String, SecretString),
119}
120
121#[derive(Debug)]
123pub struct TokenFile {
124 path: PathBuf,
125 token: SecretString,
126 expires_at: DateTime<Utc>,
127}
128
129impl TokenFile {
130 fn new<P: AsRef<Path>>(path: P) -> Result<TokenFile, Error> {
131 let token = std::fs::read_to_string(&path)
132 .map_err(|source| Error::ReadTokenFile(source, path.as_ref().to_owned()))?;
133 Ok(Self {
134 path: path.as_ref().to_owned(),
135 token: SecretString::from(token),
136 expires_at: Utc::now() + SIXTY_SEC,
138 })
139 }
140
141 fn is_expiring(&self) -> bool {
142 Utc::now() + TEN_SEC > self.expires_at
143 }
144
145 fn cached_token(&self) -> Option<&str> {
147 (!self.is_expiring()).then(|| self.token.expose_secret())
148 }
149
150 fn token(&mut self) -> &str {
152 if self.is_expiring() {
153 if let Ok(token) = std::fs::read_to_string(&self.path) {
158 self.token = SecretString::from(token);
159 }
160 self.expires_at = Utc::now() + SIXTY_SEC;
161 }
162 self.token.expose_secret()
163 }
164}
165
166macro_rules! const_unwrap {
168 ($e:expr) => {
169 match $e {
170 Some(v) => v,
171 None => panic!(),
172 }
173 };
174}
175
176pub const TEN_SEC: chrono::TimeDelta = const_unwrap!(Duration::try_seconds(10));
178const SIXTY_SEC: chrono::TimeDelta = const_unwrap!(Duration::try_seconds(60));
180
181#[derive(Debug, Clone)]
192pub enum RefreshableToken {
193 Exec(Arc<Mutex<(SecretString, DateTime<Utc>, AuthInfo)>>),
194 File(Arc<RwLock<TokenFile>>),
195 #[cfg(feature = "oauth")]
196 GcpOauth(Arc<Mutex<oauth::Gcp>>),
197 #[cfg(feature = "oidc")]
198 Oidc(Arc<Mutex<oidc::Oidc>>),
199}
200
201impl<B> AsyncPredicate<Request<B>> for RefreshableToken
203where
204 B: http_body::Body + Send + 'static,
205{
206 type Future = BoxFuture<'static, Result<Request<B>, BoxError>>;
207 type Request = Request<B>;
208
209 fn check(&mut self, mut request: Self::Request) -> Self::Future {
210 let refreshable = self.clone();
211 Box::pin(async move {
212 refreshable.to_header().await.map_err(Into::into).map(|value| {
213 request.headers_mut().insert(AUTHORIZATION, value);
214 request
215 })
216 })
217 }
218}
219
220impl RefreshableToken {
221 async fn to_header(&self) -> Result<HeaderValue, Error> {
222 match self {
223 RefreshableToken::Exec(data) => {
224 let mut locked_data = data.lock().await;
225 if Utc::now() + SIXTY_SEC >= locked_data.1 {
228 match Auth::try_from(&locked_data.2)? {
230 Auth::None | Auth::Basic(_, _) | Auth::Bearer(_) | Auth::Certificate(_, _) => {
231 return Err(Error::UnrefreshableTokenResponse);
232 }
233
234 Auth::RefreshableToken(RefreshableToken::Exec(d)) => {
235 let (new_token, new_expire, new_info) = Arc::try_unwrap(d)
236 .expect("Unable to unwrap Arc, this is likely a programming error")
237 .into_inner();
238 locked_data.0 = new_token;
239 locked_data.1 = new_expire;
240 locked_data.2 = new_info;
241 }
242
243 Auth::RefreshableToken(RefreshableToken::File(_)) => unreachable!(),
245 #[cfg(feature = "oauth")]
246 Auth::RefreshableToken(RefreshableToken::GcpOauth(_)) => unreachable!(),
247 #[cfg(feature = "oidc")]
248 Auth::RefreshableToken(RefreshableToken::Oidc(_)) => unreachable!(),
249 }
250 }
251
252 bearer_header(locked_data.0.expose_secret())
253 }
254
255 RefreshableToken::File(token_file) => {
256 let guard = token_file.read().await;
257 if let Some(header) = guard.cached_token().map(bearer_header) {
258 return header;
259 }
260 drop(guard);
262 bearer_header(token_file.write().await.token())
265 }
266
267 #[cfg(feature = "oauth")]
268 RefreshableToken::GcpOauth(data) => {
269 let gcp_oauth = data.lock().await;
270 let token = (*gcp_oauth).token().await.map_err(Error::OAuth)?;
271 bearer_header(&token.access_token)
272 }
273
274 #[cfg(feature = "oidc")]
275 RefreshableToken::Oidc(oidc) => {
276 let token = oidc.lock().await.id_token().await.map_err(Error::Oidc)?;
277 bearer_header(&token)
278 }
279 }
280 }
281}
282
283fn bearer_header(token: &str) -> Result<HeaderValue, Error> {
284 let mut value = HeaderValue::try_from(format!("Bearer {token}")).map_err(Error::InvalidBearerToken)?;
285 value.set_sensitive(true);
286 Ok(value)
287}
288
289impl TryFrom<&AuthInfo> for Auth {
290 type Error = Error;
291
292 fn try_from(auth_info: &AuthInfo) -> Result<Self, Self::Error> {
296 if let Some(provider) = &auth_info.auth_provider {
297 match token_from_provider(provider)? {
298 #[cfg(feature = "oidc")]
299 ProviderToken::Oidc(oidc) => {
300 return Ok(Self::RefreshableToken(RefreshableToken::Oidc(Arc::new(
301 Mutex::new(oidc),
302 ))));
303 }
304
305 #[cfg(not(feature = "oidc"))]
306 ProviderToken::Oidc(token) => {
307 return Ok(Self::Bearer(SecretString::from(token)));
308 }
309
310 ProviderToken::GcpCommand(token, Some(expiry)) => {
311 let mut info = auth_info.clone();
312 let mut provider = provider.clone();
313 provider.config.insert("access-token".into(), token.clone());
314 provider.config.insert("expiry".into(), expiry.to_rfc3339());
315 info.auth_provider = Some(provider);
316 return Ok(Self::RefreshableToken(RefreshableToken::Exec(Arc::new(
317 Mutex::new((SecretString::from(token), expiry, info)),
318 ))));
319 }
320
321 ProviderToken::GcpCommand(token, None) => {
322 return Ok(Self::Bearer(SecretString::from(token)));
323 }
324
325 #[cfg(feature = "oauth")]
326 ProviderToken::GcpOauth(gcp) => {
327 return Ok(Self::RefreshableToken(RefreshableToken::GcpOauth(Arc::new(
328 Mutex::new(gcp),
329 ))));
330 }
331 }
332 }
333
334 if let (Some(u), Some(p)) = (&auth_info.username, &auth_info.password) {
335 return Ok(Self::Basic(u.to_owned(), p.to_owned()));
336 }
337
338 if let Some(token) = &auth_info.token {
340 return Ok(Self::Bearer(token.clone()));
341 }
342
343 if let Some(file) = &auth_info.token_file {
345 return Ok(Self::RefreshableToken(RefreshableToken::File(Arc::new(
346 RwLock::new(TokenFile::new(file)?),
347 ))));
348 }
349
350 if let Some(exec) = &auth_info.exec {
351 let creds = auth_exec(exec)?;
352 let status = creds.status.ok_or(Error::ExecPluginFailed)?;
353 if let (Some(client_certificate_data), Some(client_key_data)) =
354 (status.client_certificate_data, status.client_key_data)
355 {
356 return Ok(Self::Certificate(client_certificate_data, client_key_data.into()));
357 }
358 let expiration = status
359 .expiration_timestamp
360 .map(|ts| ts.parse())
361 .transpose()
362 .map_err(Error::MalformedTokenExpirationDate)?;
363 match (status.token.map(SecretString::from), expiration) {
364 (Some(token), Some(expire)) => Ok(Self::RefreshableToken(RefreshableToken::Exec(Arc::new(
365 Mutex::new((token, expire, auth_info.clone())),
366 )))),
367 (Some(token), None) => Ok(Self::Bearer(token)),
368 _ => Ok(Self::None),
369 }
370 } else {
371 Ok(Self::None)
372 }
373 }
374}
375
376enum ProviderToken {
378 #[cfg(feature = "oidc")]
379 Oidc(oidc::Oidc),
380 #[cfg(not(feature = "oidc"))]
381 Oidc(String),
382 GcpCommand(String, Option<DateTime<Utc>>),
384 #[cfg(feature = "oauth")]
385 GcpOauth(oauth::Gcp),
386 }
389
390fn token_from_provider(provider: &AuthProviderConfig) -> Result<ProviderToken, Error> {
391 match provider.name.as_ref() {
392 "oidc" => token_from_oidc_provider(provider),
393 "gcp" => token_from_gcp_provider(provider),
394 "azure" => Err(Error::AuthExec(
395 "The azure auth plugin is not supported; use https://github.com/Azure/kubelogin instead".into(),
396 )),
397 _ => Err(Error::AuthExec(format!(
398 "Authentication with provider {:} not supported",
399 provider.name
400 ))),
401 }
402}
403
404#[cfg(feature = "oidc")]
405fn token_from_oidc_provider(provider: &AuthProviderConfig) -> Result<ProviderToken, Error> {
406 oidc::Oidc::from_config(&provider.config)
407 .map_err(Error::Oidc)
408 .map(ProviderToken::Oidc)
409}
410
411#[cfg(not(feature = "oidc"))]
412fn token_from_oidc_provider(provider: &AuthProviderConfig) -> Result<ProviderToken, Error> {
413 match provider.config.get("id-token") {
414 Some(id_token) => Ok(ProviderToken::Oidc(id_token.clone())),
415 None => Err(Error::AuthExec(
416 "No id-token for oidc Authentication provider".into(),
417 )),
418 }
419}
420
421fn token_from_gcp_provider(provider: &AuthProviderConfig) -> Result<ProviderToken, Error> {
422 if let Some(id_token) = provider.config.get("id-token") {
423 return Ok(ProviderToken::GcpCommand(id_token.clone(), None));
424 }
425
426 if let Some(access_token) = provider.config.get("access-token") {
428 if let Some(expiry) = provider.config.get("expiry") {
429 let expiry_date = expiry
430 .parse::<DateTime<Utc>>()
431 .map_err(Error::MalformedTokenExpirationDate)?;
432 if Utc::now() + SIXTY_SEC < expiry_date {
433 return Ok(ProviderToken::GcpCommand(access_token.clone(), Some(expiry_date)));
434 }
435 }
436 }
437
438 if let Some(cmd) = provider.config.get("cmd-path") {
440 let params = provider.config.get("cmd-args").cloned().unwrap_or_default();
441 let drop_env = provider.config.get("cmd-drop-env").cloned().unwrap_or_default();
444 let mut command = Command::new(cmd);
446 for env in drop_env.trim().split(' ') {
448 command.env_remove(env);
449 }
450 let output = command
451 .args(params.trim().split(' '))
452 .output()
453 .map_err(|e| Error::AuthExec(format!("Executing {cmd:} failed: {e:?}")))?;
454
455 if !output.status.success() {
456 return Err(Error::AuthExecRun {
457 cmd: format!("{cmd} {params}"),
458 status: output.status,
459 out: output,
460 });
461 }
462
463 if let Some(field) = provider.config.get("token-key") {
464 let json_output: serde_json::Value =
465 serde_json::from_slice(&output.stdout).map_err(Error::ParseTokenKey)?;
466 let token = extract_value(&json_output, "token-key", field)?;
467 if let Some(field) = provider.config.get("expiry-key") {
468 let expiry = extract_value(&json_output, "expiry-key", field)?;
469 let expiry = expiry
470 .parse::<DateTime<Utc>>()
471 .map_err(Error::MalformedTokenExpirationDate)?;
472 return Ok(ProviderToken::GcpCommand(token, Some(expiry)));
473 } else {
474 return Ok(ProviderToken::GcpCommand(token, None));
475 }
476 } else {
477 let token = std::str::from_utf8(&output.stdout)
478 .map_err(|e| Error::AuthExec(format!("Result is not a string {e:?} ")))?
479 .to_owned();
480 return Ok(ProviderToken::GcpCommand(token, None));
481 }
482 }
483
484 #[cfg(feature = "oauth")]
486 {
487 Ok(ProviderToken::GcpOauth(
488 oauth::Gcp::default_credentials_with_scopes(provider.config.get("scopes"))
489 .map_err(Error::OAuth)?,
490 ))
491 }
492 #[cfg(not(feature = "oauth"))]
493 {
494 Err(Error::AuthExec(
495 "Enable oauth feature to use Google Application Credentials-based token source".into(),
496 ))
497 }
498}
499
500fn extract_value(json: &serde_json::Value, context: &str, path: &str) -> Result<String, Error> {
501 let parsed_path = path
502 .trim_matches(|c| c == '"' || c == '{' || c == '}')
503 .parse::<JsonPath>()
504 .map_err(|err| {
505 Error::AuthExec(format!(
506 "Failed to parse {context:?} as a JsonPath: {path}\n
507 Error: {err}"
508 ))
509 })?;
510
511 let res = parsed_path.find_slice(json);
512
513 let Some(res) = res.into_iter().next() else {
514 return Err(Error::AuthExec(format!(
515 "Target {context:?} value {path:?} not found"
516 )));
517 };
518
519 let jval = res.to_data();
520 let val = jval.as_str().ok_or(Error::AuthExec(format!(
521 "Target {context:?} value {path:?} is not a string"
522 )))?;
523
524 Ok(val.to_string())
525}
526
527#[derive(Clone, Debug, Serialize, Deserialize)]
530pub struct ExecCredential {
531 pub kind: Option<String>,
532 #[serde(rename = "apiVersion")]
533 pub api_version: Option<String>,
534 pub spec: Option<ExecCredentialSpec>,
535 #[serde(skip_serializing_if = "Option::is_none")]
536 pub status: Option<ExecCredentialStatus>,
537}
538
539#[derive(Clone, Debug, Serialize, Deserialize)]
542pub struct ExecCredentialSpec {
543 #[serde(skip_serializing_if = "Option::is_none")]
544 interactive: Option<bool>,
545
546 #[serde(skip_serializing_if = "Option::is_none")]
547 cluster: Option<ExecAuthCluster>,
548}
549
550#[derive(Clone, Debug, Serialize, Deserialize)]
552pub struct ExecCredentialStatus {
553 #[serde(rename = "expirationTimestamp")]
554 pub expiration_timestamp: Option<String>,
555 pub token: Option<String>,
556 #[serde(rename = "clientCertificateData")]
557 pub client_certificate_data: Option<String>,
558 #[serde(rename = "clientKeyData")]
559 pub client_key_data: Option<String>,
560}
561
562fn auth_exec(auth: &ExecConfig) -> Result<ExecCredential, Error> {
563 let mut cmd = match &auth.command {
564 Some(cmd) => Command::new(cmd),
565 None => return Err(Error::MissingCommand),
566 };
567
568 if let Some(args) = &auth.args {
569 cmd.args(args);
570 }
571 if let Some(env) = &auth.env {
572 let envs = env
573 .iter()
574 .flat_map(|env| match (env.get("name"), env.get("value")) {
575 (Some(name), Some(value)) => Some((name, value)),
576 _ => None,
577 });
578 cmd.envs(envs);
579 }
580
581 let interactive = auth.interactive_mode != Some(ExecInteractiveMode::Never);
582 if interactive {
583 cmd.stdin(std::process::Stdio::inherit());
584 } else {
585 cmd.stdin(std::process::Stdio::piped());
586 }
587
588 let mut exec_credential_spec = ExecCredentialSpec {
589 interactive: Some(interactive),
590 cluster: None,
591 };
592
593 if auth.provide_cluster_info {
594 exec_credential_spec.cluster = Some(auth.cluster.clone().ok_or(Error::ExecMissingClusterInfo)?);
595 }
596
597 let exec_info = serde_json::to_string(&ExecCredential {
599 api_version: auth.api_version.clone(),
600 kind: "ExecCredential".to_string().into(),
601 spec: Some(exec_credential_spec),
602 status: None,
603 })
604 .map_err(Error::AuthExecSerialize)?;
605 cmd.env("KUBERNETES_EXEC_INFO", exec_info);
606
607 if let Some(envs) = &auth.drop_env {
608 for env in envs {
609 cmd.env_remove(env);
610 }
611 }
612
613 #[cfg(target_os = "windows")]
614 {
615 const CREATE_NO_WINDOW: u32 = 0x08000000;
616 cmd.creation_flags(CREATE_NO_WINDOW);
617 }
618
619 let out = cmd.output().map_err(Error::AuthExecStart)?;
620 if !out.status.success() {
621 return Err(Error::AuthExecRun {
622 cmd: format!("{cmd:?}"),
623 status: out.status,
624 out,
625 });
626 }
627 let creds = serde_json::from_slice(&out.stdout).map_err(Error::AuthExecParse)?;
628
629 Ok(creds)
630}
631
632#[cfg(test)]
633mod test {
634 use crate::config::Kubeconfig;
635
636 use super::*;
637 #[tokio::test]
638 #[ignore = "fails on windows mysteriously"]
639 async fn exec_auth_command() -> Result<(), Error> {
640 let expiry = (Utc::now() + SIXTY_SEC).to_rfc3339();
641 let test_file = format!(
642 r#"
643 apiVersion: v1
644 clusters:
645 - cluster:
646 certificate-authority-data: XXXXXXX
647 server: https://36.XXX.XXX.XX
648 name: generic-name
649 contexts:
650 - context:
651 cluster: generic-name
652 user: generic-name
653 name: generic-name
654 current-context: generic-name
655 kind: Config
656 preferences: {{}}
657 users:
658 - name: generic-name
659 user:
660 auth-provider:
661 config:
662 cmd-args: '{{"something": "else", "credential": {{"access_token": "my_token", "token_expiry": "{expiry}"}}}}'
663 cmd-path: echo
664 expiry-key: '{{.credential.token_expiry}}'
665 token-key: '{{.credential.access_token}}'
666 name: gcp
667 "#
668 );
669
670 let config: Kubeconfig = serde_yaml::from_str(&test_file).unwrap();
671 let auth_info = config.auth_infos[0].auth_info.as_ref().unwrap();
672 match Auth::try_from(auth_info).unwrap() {
673 Auth::RefreshableToken(RefreshableToken::Exec(refreshable)) => {
674 let (token, _expire, info) = Arc::try_unwrap(refreshable).unwrap().into_inner();
675 assert_eq!(token.expose_secret(), &"my_token".to_owned());
676 let config = info.auth_provider.unwrap().config;
677 assert_eq!(config.get("access-token"), Some(&"my_token".to_owned()));
678 }
679 _ => unreachable!(),
680 }
681 Ok(())
682 }
683
684 #[test]
685 fn token_file() {
686 let file = tempfile::NamedTempFile::new().unwrap();
687 std::fs::write(file.path(), "token1").unwrap();
688 let mut token_file = TokenFile::new(file.path()).unwrap();
689 assert_eq!(token_file.cached_token().unwrap(), "token1");
690 assert!(!token_file.is_expiring());
691 assert_eq!(token_file.token(), "token1");
692 std::fs::write(file.path(), "token2").unwrap();
694 assert_eq!(token_file.token(), "token1");
695
696 token_file.expires_at = Utc::now();
697 assert!(token_file.is_expiring());
698 assert_eq!(token_file.cached_token(), None);
699 assert_eq!(token_file.token(), "token2");
700 assert!(!token_file.is_expiring());
701 assert_eq!(token_file.cached_token().unwrap(), "token2");
702 }
703}