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1//! Run credentials: the least-privilege tokens a sandbox works with.
2//!
3//! Every sandbox run gets its own tokens, bound to the run, its repository
4//! (and the pull request's fork), what that kind of run needs to do, and an
5//! expiry no later than the run's timeout. Each carries a composite
6//! identity: an agent acting on behalf of the person who started the work.
7//! What it may do is the intersection of the two: the run's scope, and what
8//! that person may do right now.
9//!
10//! The policy lives here, as pure functions, so that identity (which mints
11//! the tokens), the API (which serves REST and MCP) and repos (which serves
12//! git) all enforce the same rules, and so the rules can be tested.
13
14use serde::{Deserialize, Serialize};
15
16use crate::identity::AgentScope;
17use crate::repos::RepoPath;
18use crate::access::{BasePermission, RepoGrant, RepoRole};
19use crate::{Membership, PrincipalKind, Role, User};
20
21/// What a run does, as far as its credentials are concerned. The same names
22/// as [`crate::agents::RunKind`], plus `deploy`, a build of one commit.
23#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
24#[serde(rename_all = "snake_case")]
25pub enum RunCredentialKind {
26 Implement,
27 Revise,
28 Review,
29 Answer,
30 Update,
31 Plan,
32 Checks,
33 Queue,
34 Mergecheck,
35 Deploy,
36 /// A security update: raising one package's version in its lockfiles
37 /// and pushing that to a branch of its own. Not an agent.
38 Bump,
39}
40
41impl RunCredentialKind {
42 pub const ALL: [RunCredentialKind; 11] = [
43 RunCredentialKind::Implement,
44 RunCredentialKind::Revise,
45 RunCredentialKind::Review,
46 RunCredentialKind::Answer,
47 RunCredentialKind::Update,
48 RunCredentialKind::Plan,
49 RunCredentialKind::Checks,
50 RunCredentialKind::Queue,
51 RunCredentialKind::Mergecheck,
52 RunCredentialKind::Deploy,
53 RunCredentialKind::Bump,
54 ];
55
56 pub fn as_str(self) -> &'static str {
57 match self {
58 RunCredentialKind::Implement => "implement",
59 RunCredentialKind::Revise => "revise",
60 RunCredentialKind::Review => "review",
61 RunCredentialKind::Answer => "answer",
62 RunCredentialKind::Update => "update",
63 RunCredentialKind::Plan => "plan",
64 RunCredentialKind::Checks => "checks",
65 RunCredentialKind::Queue => "queue",
66 RunCredentialKind::Mergecheck => "mergecheck",
67 RunCredentialKind::Deploy => "deploy",
68 RunCredentialKind::Bump => "bump",
69 }
70 }
71
72 /// Whether the run works on one pull request, whose session and
73 /// readiness it reports.
74 fn works_on_a_pull(self) -> bool {
75 matches!(
76 self,
77 RunCredentialKind::Implement
78 | RunCredentialKind::Revise
79 | RunCredentialKind::Answer
80 | RunCredentialKind::Update
81 )
82 }
83}
84
85/// Which part of a sandbox a credential is for.
86#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
87#[serde(rename_all = "snake_case")]
88pub enum CredentialUse {
89 /// g1t's runner: cloning, pushing the result, recording the session.
90 /// It acts as the person downstream, so that what it pushes and records
91 /// is theirs, within the run's scope.
92 Runner,
93 /// The agent's own tools, over MCP. It acts as the agent.
94 Tools,
95}
96
97impl CredentialUse {
98 pub fn as_str(self) -> &'static str {
99 match self {
100 CredentialUse::Runner => "runner",
101 CredentialUse::Tools => "tools",
102 }
103 }
104}
105
106/// A repository a run may push to, and the one branch, if only one.
107#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
108pub struct GitGrant {
109 pub repo: RepoPath,
110 /// Null: any branch. A pull request's fork is its own repository, so
111 /// the whole of it is the pull request's.
112 #[serde(default)]
113 pub branch: Option<String>,
114}
115
116/// What binds an agent's token to one run. Absent on agent tokens made
117/// before run credentials, which keep working for the API only.
118#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
119#[serde(rename_all = "camelCase")]
120pub struct RunBinding {
121 pub kind: RunCredentialKind,
122 #[serde(rename = "use")]
123 pub usage: CredentialUse,
124 /// The agent run, once the sandbox has recorded it.
125 #[serde(default)]
126 pub run_id: Option<String>,
127 /// The pull request the run works on, for the kinds that work on one.
128 #[serde(default)]
129 pub number: Option<u32>,
130 /// The agent's name, such as `g1t`.
131 pub agent: String,
132 /// Repositories it may clone and fetch, besides those it may push to.
133 #[serde(default)]
134 pub read: Vec<RepoPath>,
135 /// Where it may push.
136 #[serde(default)]
137 pub push: Vec<GitGrant>,
138 /// g1t's own run (a security update, an agent g1t put on one): the
139 /// credential belongs to the workspace, and acts on behalf of g1t
140 /// (`system::ID`), so what it does is g1t's, and the pull request g1t
141 /// opened, and its working copy, are its own.
142 #[serde(default, skip_serializing_if = "std::ops::Not::not")]
143 pub system: bool,
144}
145
146/// A person, by id and name.
147#[derive(Clone, Debug, Default, PartialEq, Eq, Serialize, Deserialize)]
148pub struct Principal {
149 pub id: String,
150 pub username: String,
151}
152
153impl From<&User> for Principal {
154 fn from(user: &User) -> Self {
155 Principal {
156 id: user.id.clone(),
157 username: user.username.clone(),
158 }
159 }
160}
161
162/// Set on a [`User`] resolved from an agent's token: the composite
163/// identity, "g1t on behalf of syntaqx", and what it may do.
164#[derive(Clone, Debug, Serialize, Deserialize)]
165#[serde(rename_all = "camelCase")]
166pub struct Acting {
167 /// The token's id, as audit entries name it.
168 pub credential_id: String,
169 pub agent: String,
170 pub on_behalf_of: Principal,
171 pub scope: AgentScope,
172}
173
174impl Acting {
175 pub fn run(&self) -> Option<&RunBinding> {
176 self.scope.run.as_ref()
177 }
178}
179
180/// `create_run_credential`: a token for one sandbox run. It acts as
181/// `agent` on behalf of `on_behalf_of`, can do only what `kind` and `usage`
182/// allow in `repo`, and expires after `ttl_seconds`, which should be the
183/// run's timeout. Returns `CreatedAccessToken`.
184#[derive(Clone, Debug, Serialize, Deserialize)]
185#[serde(rename_all = "camelCase")]
186pub struct CreateRunCredentialArgs {
187 pub on_behalf_of: User,
188 pub repo: RepoPath,
189 pub kind: RunCredentialKind,
190 #[serde(rename = "use")]
191 pub usage: CredentialUse,
192 #[serde(default)]
193 pub number: Option<u32>,
194 #[serde(default)]
195 pub read: Vec<RepoPath>,
196 #[serde(default)]
197 pub push: Vec<GitGrant>,
198 pub ttl_seconds: u64,
199 /// Defaults to `g1t`.
200 #[serde(default)]
201 pub agent: Option<String>,
202}
203
204/// `bind_run_credentials`: ties tokens, named by the SHA-256 of their
205/// text in hex, to the agent run their sandbox recorded. Returns how many.
206#[derive(Clone, Debug, Serialize, Deserialize)]
207#[serde(rename_all = "camelCase")]
208pub struct BindRunCredentialsArgs {
209 pub token_hashes: Vec<String>,
210 pub run_id: String,
211}
212
213/// `revoke_run_credentials`: ends tokens when their sandbox stops, by hash
214/// or by run. Only run credentials are touched, never a token a person
215/// made. Returns how many.
216#[derive(Clone, Debug, Default, Serialize, Deserialize)]
217#[serde(rename_all = "camelCase")]
218pub struct RevokeRunCredentialsArgs {
219 #[serde(default)]
220 pub token_hashes: Vec<String>,
221 #[serde(default)]
222 pub run_id: Option<String>,
223}
224
225// --- Policy --------------------------------------------------------------
226
227/// Operations that only read.
228pub const READ_OPERATIONS: &[&str] = &[
229 "whoami",
230 "get_usage",
231 "get_budget",
232 "get_ai_credit",
233 "list_invoices",
234 "get_billing_details",
235 "list_repos",
236 "get_repo",
237 "list_projects",
238 "get_project",
239 "list_deleted_repos",
240 "list_collaborators",
241 "get_collaborator_permission",
242 "list_repo_invitations",
243 "list_my_repo_invitations",
244 "list_outside_collaborators",
245 "list_teams",
246 "get_team",
247 "list_team_members",
248 "list_child_teams",
249 "list_team_repos",
250 "list_user_teams",
251 "get_codeowners_errors",
252 "get_repo_settings",
253 "list_check_names",
254 "get_merge_queue",
255 "recall",
256 "list_issues",
257 "get_issue",
258 "get_plan",
259 "list_labels",
260 "list_issue_labels",
261 "list_milestones",
262 "get_milestone",
263 "list_pull_requests",
264 "get_pull_request",
265 "read_session",
266 "get_pull_request_changes",
267 "list_events",
268 "get_context",
269 "search_context",
270 "get_entity",
271 "search",
272 "list_workflows",
273 "list_workflow_runs",
274 "get_workflow_run",
275 "get_job_logs",
276 "get_pending_deployments",
277 "get_workflow_permissions",
278 "get_fork_pr_approval",
279 "list_commit_statuses",
280 "get_combined_status",
281 "list_check_runs_for_ref",
282 "get_check_run",
283 "list_check_run_annotations",
284 "list_check_suites_for_ref",
285 "get_check_suite",
286 "list_integrations",
287 "get_model_routes",
288 "list_webhooks",
289 "list_webhook_deliveries",
290 "list_actions_secrets",
291 "list_actions_variables",
292 "list_security_alerts",
293 "list_secret_scanning_alerts",
294 "get_secret_scanning_alert",
295 "list_secret_scanning_locations",
296 "list_bypass_requests",
297 "list_custom_patterns",
298 "list_code_scanning_alerts",
299 "get_code_scanning_alert",
300 "list_code_scanning_analyses",
301 "get_sarif_upload",
302 "list_vulnerability_alerts",
303 "get_vulnerability_alert",
304 "get_dependency_graph",
305 "get_sbom",
306 "compare_dependencies",
307 "get_security_settings",
308 "get_workspace_security_settings",
309 "get_security_overview",
310 "list_security_advisories",
311 "get_security_advisory",
312 "list_vulnerability_reports",
313 "list_notifications",
314 "get_notification_thread",
315 "get_thread_subscription",
316 "get_repo_subscription",
317 "list_watched_repos",
318 "list_pinned_projects",
319];
320
321/// What no agent's token may ever do, whatever its scope says: workspaces,
322/// repositories' settings, members, tokens, billing, integrations,
323/// webhooks, secrets, workflows' controls, merging, and putting more agents
324/// to work.
325pub const NEVER: &[&str] = &[
326 // Billing is people's: agents never spend or change it.
327 "set_budget",
328 "buy_ai_credit",
329 "create_workspace",
330 "delete_workspace",
331 "update_workspace",
332 // So is who belongs to a workspace and who owns it.
333 "list_members",
334 "update_member",
335 "remove_member",
336 "transfer_ownership",
337 "leave_workspace",
338 "transfer_repo",
339 "create_repo",
340 "update_repo",
341 "update_project",
342 "delete_repo",
343 "list_deleted_repos",
344 "restore_repo",
345 "purge_repo",
346 "rename_repo",
347 "archive_repo",
348 "unarchive_repo",
349 "set_repo_visibility",
350 "rename_branch",
351 "update_repo_settings",
352 "merge_pull_request",
353 "assign_issue",
354 "plan_work",
355 "apply_plan",
356 "import_issue",
357 "list_integrations",
358 "connect_integration",
359 "update_integration",
360 "disconnect_integration",
361 "test_integration",
362 "get_model_routes",
363 "set_model_routes",
364 "list_webhooks",
365 "create_webhook",
366 "update_webhook",
367 "delete_webhook",
368 "ping_webhook",
369 "list_webhook_deliveries",
370 "redeliver_webhook",
371 "dispatch_workflow",
372 "cancel_workflow_run",
373 "rerun_workflow_run",
374 "update_workflow",
375 // Nor lets runs or deployments through, or changes what holds them.
376 "approve_workflow_run",
377 "review_pending_deployments",
378 "update_environment",
379 "delete_environment",
380 "set_workflow_permissions",
381 "set_fork_pr_approval",
382 "set_actions_access",
383 "create_repository_dispatch",
384 "set_workspace_workflow_permissions",
385 // An agent never reports checks on its own work, nor asks for them
386 // to run again: what checks say is the integrations' to say.
387 "create_commit_status",
388 "create_check_run",
389 "update_check_run",
390 "rerequest_check_run",
391 "rerequest_check_suite",
392 "list_actions_secrets",
393 "set_actions_secret",
394 "delete_actions_secret",
395 "list_actions_variables",
396 "set_actions_variable",
397 "delete_actions_variable",
398 "list_collaborators",
399 "get_collaborator_permission",
400 "add_collaborator",
401 "update_collaborator",
402 "remove_collaborator",
403 "list_repo_invitations",
404 "revoke_repo_invitation",
405 "list_my_repo_invitations",
406 "accept_repo_invitation",
407 "decline_repo_invitation",
408 // Nor answers a workspace invitation: only the person it is for does.
409 "accept_invitation",
410 "decline_invitation",
411 "set_base_permission",
412 "list_outside_collaborators",
413 // Deploy keys, which let a machine into a repository.
414 "list_deploy_keys",
415 "get_deploy_key",
416 "create_deploy_key",
417 "delete_deploy_key",
418 // Moving a repository to g1t for good, and a remote's token and
419 // levers, are a person's to decide.
420 "move_mirror_to_g1t",
421 "add_mirror_remote",
422 "update_mirror_remote",
423 "remove_mirror_remote",
424 // Teams: who is in which, and what they reach, is for people.
425 "create_team",
426 "update_team",
427 "delete_team",
428 "set_team_member",
429 "remove_team_member",
430 "set_team_repo",
431 "remove_team_repo",
432 "set_team_review_assignment",
433 // Dismissing a secret lets it through push protection.
434 "dismiss_security_alert",
435 "reopen_security_alert",
436 // Nor any other decision about security: closing or reopening an
437 // alert, pushing past push protection or deciding who may, changing
438 // what is looked for or when checks fail, or putting more agents to
439 // work. An agent fixes what it finds in its own pull request.
440 "update_secret_scanning_alert",
441 "bypass_push_protection",
442 "review_bypass_request",
443 "create_custom_pattern",
444 "update_custom_pattern",
445 "delete_custom_pattern",
446 "update_code_scanning_alert",
447 "update_vulnerability_alert",
448 "fix_security_alert",
449 "update_security_settings",
450 "update_workspace_security_settings",
451 // A person's own inbox: g1t's agents act as g1t, which has none.
452 "list_notifications",
453 "get_notification_thread",
454 "mark_notifications_read",
455 "mark_thread_read",
456 "mark_thread_done",
457 "save_thread",
458 "snooze_thread",
459 "get_thread_subscription",
460 "set_thread_subscription",
461 "delete_thread_subscription",
462 "get_repo_subscription",
463 "set_repo_subscription",
464 "delete_repo_subscription",
465 "list_watched_repos",
466 // Pins are a person's own, as the inbox is.
467 "list_pinned_projects",
468 "pin_project",
469 "unpin_project",
470 "reorder_pinned_projects",
471 // Deleting packages and deciding who may use them is for people: an
472 // agent publishes its repository's packages and never deletes them.
473 "update_package",
474 "link_package",
475 "unlink_package",
476 "set_package_access",
477 "remove_package_access",
478 "set_package_actions_access",
479 "remove_package_actions_access",
480 "delete_package",
481 "restore_package",
482 "delete_package_version",
483 "restore_package_version",
484 // Sharing an artifact and deleting one for good are for people: an
485 // agent shares only through the agents service, with the people
486 // already in its conversation.
487 "set_workspace_artifact_access",
488 "purge_workspace_artifact",
489];
490
491/// Reading what an agent needs to know about its repository.
492const TOOLS_READ: &[&str] = &[
493 "get_repo",
494 "list_issues",
495 "get_issue",
496 "list_labels",
497 "list_issue_labels",
498 "list_milestones",
499 "get_milestone",
500 "list_pull_requests",
501 "get_pull_request",
502 "get_pull_request_changes",
503 "read_session",
504 "get_merge_queue",
505 "list_events",
506 "recall",
507 "search_context",
508 "get_entity",
509 "search",
510 "list_workflows",
511 "list_workflow_runs",
512 "get_workflow_run",
513 "get_job_logs",
514 "get_pending_deployments",
515 "get_workflow_permissions",
516 "get_fork_pr_approval",
517 "list_commit_statuses",
518 "get_combined_status",
519 "list_check_runs_for_ref",
520 "get_check_run",
521 "list_check_run_annotations",
522 "list_check_suites_for_ref",
523 "get_check_suite",
524];
525
526pub fn is_read(operation: &str) -> bool {
527 READ_OPERATIONS.contains(&operation)
528}
529
530/// The API and MCP operations a run of `kind` may use with a credential
531/// for `usage`. Git is separate: see [`decide_git`].
532pub fn operations_for(kind: RunCredentialKind, usage: CredentialUse) -> Vec<&'static str> {
533 use RunCredentialKind as K;
534 let mut operations: Vec<&'static str> = Vec::new();
535 match usage {
536 CredentialUse::Runner => {
537 if kind.works_on_a_pull() {
538 operations.extend(["get_repo", "get_pull_request", "record_session"]);
539 }
540 if kind == K::Implement {
541 operations.push("mark_pull_request_ready");
542 }
543 }
544 CredentialUse::Tools => match kind {
545 K::Implement | K::Revise | K::Answer => {
546 operations.extend(TOOLS_READ.iter().copied());
547 operations.extend([
548 "create_issue",
549 "add_comment",
550 "take_messages",
551 "remember",
552 "message_agent",
553 "answer_message",
554 "get_context",
555 "customize_bundle",
556 ]);
557 }
558 K::Review => {
559 operations.extend(TOOLS_READ.iter().copied());
560 operations.extend(["add_comment", "review_pull_request", "get_context", "customize_bundle"]);
561 }
562 K::Plan => {
563 operations.extend(TOOLS_READ.iter().copied());
564 operations.extend(["create_issue", "get_context", "customize_bundle"]);
565 }
566 K::Update => {
567 operations.extend(TOOLS_READ.iter().copied());
568 operations.push("customize_bundle");
569 }
570 K::Checks | K::Queue | K::Mergecheck | K::Deploy | K::Bump => {}
571 },
572 }
573 operations
574}
575
576/// What a run's credential may do, in the scope vocabulary that access
577/// tokens use (see [`crate::scopes`]): the scopes of its operations, and
578/// for a runner, git's. Its operations, its repository and its run still
579/// bound it more tightly than these scopes say.
580pub fn run_scopes(kind: RunCredentialKind, usage: CredentialUse) -> Vec<crate::scopes::Scope> {
581 use crate::scopes::{Scope, normalize, scope_for};
582 let mut scopes: Vec<Scope> = operations_for(kind, usage)
583 .into_iter()
584 .filter_map(scope_for)
585 .collect();
586 if usage == CredentialUse::Runner {
587 scopes.push(Scope::CodeRead);
588 if matches!(
589 kind,
590 RunCredentialKind::Implement
591 | RunCredentialKind::Revise
592 | RunCredentialKind::Answer
593 | RunCredentialKind::Update
594 | RunCredentialKind::Bump
595 ) {
596 scopes.push(Scope::CodeWrite);
597 }
598 }
599 normalize(&mut scopes);
600 scopes
601}
602
603/// Operations that change a pull request, which a runner may do only to
604/// the pull request its run works on.
605const PULL_WRITES: &[&str] = &["record_session", "mark_pull_request_ready"];
606
607/// Whether something was allowed, and the rule that decided it.
608#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
609pub struct Decision {
610 pub allowed: bool,
611 /// A short, stable name: `run:implement/tools`, `never`,
612 /// `scope:repository` and so on. Shown in the audit log.
613 pub rule: String,
614 /// Why it was refused, for the caller.
615 #[serde(default, skip_serializing_if = "Option::is_none")]
616 pub reason: Option<String>,
617}
618
619impl Decision {
620 pub fn allow(rule: impl Into<String>) -> Self {
621 Decision {
622 allowed: true,
623 rule: rule.into(),
624 reason: None,
625 }
626 }
627
628 pub fn deny(rule: impl Into<String>, reason: impl Into<String>) -> Self {
629 Decision {
630 allowed: false,
631 rule: rule.into(),
632 reason: Some(reason.into()),
633 }
634 }
635}
636
637fn same_repo(a: &RepoPath, b: &RepoPath) -> bool {
638 a.namespace.eq_ignore_ascii_case(&b.namespace) && a.name.eq_ignore_ascii_case(&b.name)
639}
640
641fn scope_rule(scope: &AgentScope) -> String {
642 match &scope.run {
643 Some(run) => format!("run:{}/{}", run.kind.as_str(), run.usage.as_str()),
644 None => "agent-token".to_owned(),
645 }
646}
647
648/// Whether `user`, resolved from an agent's token with `scope`, may use
649/// `operation`. `repo` is the repository the call names, if any, and
650/// `needs_repo` whether the operation is about one; `number` the issue or
651/// pull request it names.
652pub fn decide_operation(
653 user: &User,
654 scope: &AgentScope,
655 operation: &str,
656 repo: Option<&RepoPath>,
657 needs_repo: bool,
658 number: Option<u32>,
659) -> Decision {
660 let who = "A g1t agent's token";
661 if NEVER.contains(&operation) {
662 return Decision::deny(
663 "never",
664 format!(
665 "{who} can never use {operation}: settings, members, tokens, billing, integrations, webhooks, secrets and merging are for people."
666 ),
667 );
668 }
669 if !scope.operations.iter().any(|name| name == operation) {
670 return Decision::deny(
671 "scope:operation",
672 format!("{who} for this run cannot use {operation}."),
673 );
674 }
675 if needs_repo && !repo.is_some_and(|asked| same_repo(asked, &scope.repo)) {
676 return Decision::deny(
677 "scope:repository",
678 format!(
679 "{who} works in {}/{} only.",
680 scope.repo.namespace, scope.repo.name
681 ),
682 );
683 }
684 // The intersection: the person it acts for must still be able to work
685 // in the repository's workspace, as a member or with a role on its
686 // repositories. What it may do in the repository itself is their
687 // role there, which services check (`access::can`).
688 if !crate::access::has_access_in(user, &scope.repo.namespace) {
689 return Decision::deny(
690 "on-behalf-of:membership",
691 format!(
692 "The person this agent works for is no longer a member of {}.",
693 scope.repo.namespace
694 ),
695 );
696 }
697 if let Some(run) = &scope.run
698 && run.usage == CredentialUse::Runner
699 && PULL_WRITES.contains(&operation)
700 && run.number.is_some()
701 && number != run.number
702 {
703 return Decision::deny(
704 "scope:pull",
705 format!(
706 "{who} can change pull request #{} only.",
707 run.number.unwrap_or_default()
708 ),
709 );
710 }
711 Decision::allow(scope_rule(scope))
712}
713
714/// Whether a run credential may clone or fetch (`write` false), or push to
715/// (`write` true), the repository at `repo`.
716pub fn decide_git(scope: &AgentScope, repo: &RepoPath, write: bool) -> Decision {
717 let Some(run) = scope
718 .run
719 .as_ref()
720 .filter(|run| run.usage == CredentialUse::Runner)
721 else {
722 return Decision::deny(
723 "git:not-a-run",
724 "A g1t agent's tools token cannot be used with git.",
725 );
726 };
727 let pushable = run.push.iter().any(|grant| same_repo(&grant.repo, repo));
728 if write {
729 return if pushable {
730 Decision::allow(format!("{}:push", scope_rule(scope)))
731 } else {
732 Decision::deny(
733 "git:push",
734 format!(
735 "A {} run cannot push to {}/{}.",
736 run.kind.as_str(),
737 repo.namespace,
738 repo.name
739 ),
740 )
741 };
742 }
743 let readable = pushable
744 || same_repo(&scope.repo, repo)
745 || run.read.iter().any(|path| same_repo(path, repo));
746 if readable {
747 Decision::allow(format!("{}:read", scope_rule(scope)))
748 } else {
749 Decision::deny(
750 "git:read",
751 format!(
752 "A {} run cannot read {}/{}.",
753 run.kind.as_str(),
754 repo.namespace,
755 repo.name
756 ),
757 )
758 }
759}
760
761/// Whether a push to `repo` is limited to certain branches, so that the
762/// refs it moves have to be read and checked with [`decide_refs`].
763pub fn limits_branches(scope: &AgentScope, repo: &RepoPath) -> bool {
764 scope
765 .run
766 .iter()
767 .flat_map(|run| run.push.iter())
768 .any(|grant| same_repo(&grant.repo, repo) && grant.branch.is_some())
769}
770
771/// Whether a push to `repo` may move `refs` (full refs, such as
772/// `refs/heads/main`). Tags are never a run's to move.
773pub fn decide_refs(scope: &AgentScope, repo: &RepoPath, refs: &[String]) -> Decision {
774 let repo_decision = decide_git(scope, repo, true);
775 if !repo_decision.allowed {
776 return repo_decision;
777 }
778 let grants: Vec<&GitGrant> = scope
779 .run
780 .iter()
781 .flat_map(|run| run.push.iter())
782 .filter(|grant| same_repo(&grant.repo, repo))
783 .collect();
784 for git_ref in refs {
785 let Some(branch) = git_ref.strip_prefix("refs/heads/") else {
786 return Decision::deny("git:ref", format!("A run cannot push {git_ref}."));
787 };
788 let allowed = grants
789 .iter()
790 .any(|grant| grant.branch.as_deref().is_none_or(|only| only == branch));
791 if !allowed {
792 return Decision::deny(
793 "git:ref",
794 format!(
795 "A run cannot push to {branch} in {}/{}.",
796 repo.namespace, repo.name
797 ),
798 );
799 }
800 }
801 repo_decision
802}
803
804/// The most an agent may be on a repository, whoever it works for: it
805/// can push, merge and run, never change settings or who has access.
806pub const AGENT_CEILING: RepoRole = RepoRole::Write;
807
808/// The memberships an agent working for `person` has: the run's
809/// workspace, as a member, only if the person is in it now, with the
810/// person's role on its repositories (an owner's Admin included) cut down
811/// to [`AGENT_CEILING`].
812pub fn intersect(person: &[Membership], namespace: &str) -> Vec<Membership> {
813 let namespace = namespace.to_lowercase();
814 person
815 .iter()
816 .filter(|membership| membership.slug == namespace)
817 .map(|membership| {
818 let base = match membership.role {
819 Role::Owner => BasePermission::Admin,
820 Role::Member => membership.base_permission.unwrap_or_default(),
821 };
822 Membership {
823 role: Role::Member,
824 base_permission: Some(match base {
825 BasePermission::Admin => BasePermission::Write,
826 base => base,
827 }),
828 // Billing and security manager are the person's, never
829 // their agent's.
830 org_roles: Vec::new(),
831 ..membership.clone()
832 }
833 })
834 .collect()
835}
836
837/// The repository grants an agent working for `person` has: those in the
838/// run's workspace, each cut down to [`AGENT_CEILING`].
839pub fn intersect_grants(person: &[RepoGrant], namespace: &str) -> Vec<RepoGrant> {
840 let namespace = namespace.to_lowercase();
841 person
842 .iter()
843 .filter(|grant| grant.workspace == namespace)
844 .map(|grant| RepoGrant {
845 role: grant.role.min(AGENT_CEILING),
846 ..grant.clone()
847 })
848 .collect()
849}
850
851/// Who a runner's credential acts as downstream: the person, with only the
852/// agent's (already intersected) memberships. `None` for anything else.
853pub fn as_person(user: &User) -> Option<User> {
854 let acting = user.acting.as_ref()?;
855 if user.kind != PrincipalKind::Agent {
856 return None;
857 }
858 let run = acting.run()?;
859 if run.usage != CredentialUse::Runner {
860 return None;
861 }
862 Some(User {
863 id: acting.on_behalf_of.id.clone(),
864 username: acting.on_behalf_of.username.clone(),
865 display_username: None,
866 kind: PrincipalKind::User,
867 verified: user.verified,
868 workspaces: user.workspaces.clone(),
869 avatar: None,
870 acting: None,
871 grants: user.grants.clone(),
872 token: None,
873 held: Vec::new(),
874 })
875}
876
877/// How an actor is described: "g1t on behalf of syntaqx".
878pub fn describe(user: &User) -> String {
879 match &user.acting {
880 Some(acting) => format!(
881 "{} on behalf of {}",
882 acting.agent, acting.on_behalf_of.username
883 ),
884 None => user.username.clone(),
885 }
886}
887
888#[cfg(test)]
889mod tests {
890 use super::*;
891
892 #[test]
893 fn a_run_s_scopes_are_never_admin() {
894 for kind in RunCredentialKind::ALL {
895 for usage in [CredentialUse::Runner, CredentialUse::Tools] {
896 let scopes = run_scopes(kind, usage);
897 assert!(scopes.iter().all(|scope| !scope.dangerous()), "{kind:?} {usage:?}: {scopes:?}");
898 }
899 }
900 let review = run_scopes(RunCredentialKind::Review, CredentialUse::Tools);
901 assert!(review.contains(&crate::scopes::Scope::PullRequestsWrite));
902 assert!(!review.contains(&crate::scopes::Scope::CodeWrite));
903 }
904
905 #[test]
906 fn agents_can_search_the_context_hub() {
907 for kind in [RunCredentialKind::Implement, RunCredentialKind::Review, RunCredentialKind::Plan] {
908 let tools = operations_for(kind, CredentialUse::Tools);
909 assert!(tools.contains(&"search_context") && tools.contains(&"get_entity"));
910 }
911 assert!(is_read("search_context") && is_read("get_entity"));
912 }
913
914 #[test]
915 fn agents_can_search_all_of_g1t() {
916 // Site-wide search only reads: every run that reads its repository
917 // may use it, and nothing that never reads gets it.
918 assert!(is_read("search"));
919 assert!(!NEVER.contains(&"search"));
920 for kind in [
921 RunCredentialKind::Implement,
922 RunCredentialKind::Revise,
923 RunCredentialKind::Answer,
924 RunCredentialKind::Review,
925 RunCredentialKind::Plan,
926 RunCredentialKind::Update,
927 ] {
928 let tools = operations_for(kind, CredentialUse::Tools);
929 assert!(tools.contains(&"search"), "{kind:?} should search");
930 // The context hub's search stays its own tool beside it.
931 assert!(tools.contains(&"search_context"), "{kind:?} keeps search_context");
932 }
933 for kind in [RunCredentialKind::Checks, RunCredentialKind::Queue, RunCredentialKind::Mergecheck, RunCredentialKind::Deploy, RunCredentialKind::Bump] {
934 assert!(!operations_for(kind, CredentialUse::Tools).contains(&"search"));
935 }
936 assert!(!operations_for(RunCredentialKind::Implement, CredentialUse::Runner).contains(&"search"));
937 }
938
939 fn path(namespace: &str, name: &str) -> RepoPath {
940 RepoPath {
941 namespace: namespace.to_owned(),
942 name: name.to_owned(),
943 }
944 }
945
946 fn scope(kind: RunCredentialKind, usage: CredentialUse) -> AgentScope {
947 AgentScope {
948 repo: path("acme", "rocket"),
949 operations: operations_for(kind, usage)
950 .into_iter()
951 .map(str::to_owned)
952 .collect(),
953 run: Some(RunBinding {
954 kind,
955 usage,
956 run_id: Some("run_1".to_owned()),
957 number: Some(7),
958 agent: "g1t".to_owned(),
959 system: false,
960 read: vec![path("acme", "rocket")],
961 push: match kind {
962 RunCredentialKind::Implement
963 | RunCredentialKind::Revise
964 | RunCredentialKind::Answer => vec![GitGrant {
965 repo: path("pulls", "pul_7"),
966 branch: None,
967 }],
968 RunCredentialKind::Update => vec![GitGrant {
969 repo: path("acme", "rocket"),
970 branch: Some("fix-login".to_owned()),
971 }],
972 _ => vec![],
973 },
974 }),
975 }
976 }
977
978 fn agent(member_of: &[&str], scope: AgentScope) -> User {
979 User {
980 id: "usr_g1t_agent".to_owned(),
981 username: "g1t".to_owned(),
982 display_username: None,
983 kind: PrincipalKind::Agent,
984 verified: true,
985 workspaces: member_of
986 .iter()
987 .map(|slug| Membership::member(*slug))
988 .collect(),
989 avatar: None,
990 grants: Vec::new(),
991 token: None,
992 held: Vec::new(),
993 acting: Some(Box::new(Acting {
994 credential_id: "tok_1".to_owned(),
995 agent: "g1t".to_owned(),
996 on_behalf_of: Principal {
997 id: "usr_1".to_owned(),
998 username: "syntaqx".to_owned(),
999 },
1000 scope,
1001 })),
1002 }
1003 }
1004
1005 fn op(kind: RunCredentialKind, usage: CredentialUse, operation: &str) -> Decision {
1006 let scope = scope(kind, usage);
1007 let user = agent(&["acme"], scope.clone());
1008 decide_operation(
1009 &user,
1010 &scope,
1011 operation,
1012 Some(&path("acme", "rocket")),
1013 true,
1014 Some(7),
1015 )
1016 }
1017
1018 use CredentialUse::{Runner, Tools};
1019 use RunCredentialKind as K;
1020
1021 /// Which operations each kind of run may use through its tools: the
1022 /// allowed and denied matrix.
1023 #[test]
1024 fn tools_matrix() {
1025 let cases: [(&str, [bool; 6]); 12] = [
1026 // implement revise answer review plan checks
1027 ("get_issue", [true, true, true, true, true, false]),
1028 ("create_issue", [true, true, true, false, true, false]),
1029 ("add_comment", [true, true, true, true, false, false]),
1030 (
1031 "review_pull_request",
1032 [false, false, false, true, false, false],
1033 ),
1034 ("remember", [true, true, true, false, false, false]),
1035 ("take_messages", [true, true, true, false, false, false]),
1036 ("record_session", [false, false, false, false, false, false]),
1037 (
1038 "merge_pull_request",
1039 [false, false, false, false, false, false],
1040 ),
1041 (
1042 "update_repo_settings",
1043 [false, false, false, false, false, false],
1044 ),
1045 ("create_webhook", [false, false, false, false, false, false]),
1046 (
1047 "set_actions_secret",
1048 [false, false, false, false, false, false],
1049 ),
1050 ("assign_issue", [false, false, false, false, false, false]),
1051 ];
1052 let kinds = [
1053 K::Implement,
1054 K::Revise,
1055 K::Answer,
1056 K::Review,
1057 K::Plan,
1058 K::Checks,
1059 ];
1060 for (operation, expected) in cases {
1061 for (kind, allowed) in kinds.into_iter().zip(expected) {
1062 assert_eq!(
1063 op(kind, Tools, operation).allowed,
1064 allowed,
1065 "{operation} by a {} run's tools",
1066 kind.as_str()
1067 );
1068 }
1069 }
1070 }
1071
1072 #[test]
1073 fn runner_matrix() {
1074 assert!(op(K::Implement, Runner, "record_session").allowed);
1075 assert!(op(K::Implement, Runner, "mark_pull_request_ready").allowed);
1076 assert!(op(K::Revise, Runner, "record_session").allowed);
1077 assert!(!op(K::Revise, Runner, "mark_pull_request_ready").allowed);
1078 assert!(!op(K::Implement, Runner, "create_issue").allowed);
1079 assert!(!op(K::Review, Runner, "record_session").allowed);
1080 assert!(!op(K::Checks, Runner, "get_issue").allowed);
1081 }
1082
1083 #[test]
1084 fn settings_billing_tokens_and_members_are_never_reachable() {
1085 for kind in RunCredentialKind::ALL {
1086 for usage in [Runner, Tools] {
1087 for operation in NEVER.iter().copied() {
1088 let decision = op(kind, usage, operation);
1089 assert!(!decision.allowed);
1090 assert_eq!(decision.rule, "never");
1091 }
1092 }
1093 }
1094 // Even a scope that lists one is refused.
1095 let mut wide = scope(K::Implement, Tools);
1096 wide.operations.push("merge_pull_request".to_owned());
1097 let user = agent(&["acme"], wide.clone());
1098 let decision = decide_operation(
1099 &user,
1100 &wide,
1101 "merge_pull_request",
1102 Some(&path("acme", "rocket")),
1103 true,
1104 Some(7),
1105 );
1106 assert_eq!(decision.rule, "never");
1107 }
1108
1109 #[test]
1110 fn another_repository_is_refused() {
1111 let scope = scope(K::Implement, Tools);
1112 let user = agent(&["acme"], scope.clone());
1113 let decision = decide_operation(
1114 &user,
1115 &scope,
1116 "create_issue",
1117 Some(&path("acme", "other")),
1118 true,
1119 None,
1120 );
1121 assert!(!decision.allowed);
1122 assert_eq!(decision.rule, "scope:repository");
1123 let decision = decide_operation(&user, &scope, "create_issue", None, true, None);
1124 assert_eq!(decision.rule, "scope:repository");
1125 // The repository's name is matched without regard to case.
1126 let decision = decide_operation(
1127 &user,
1128 &scope,
1129 "create_issue",
1130 Some(&path("Acme", "Rocket")),
1131 true,
1132 None,
1133 );
1134 assert!(decision.allowed);
1135 assert_eq!(decision.rule, "run:implement/tools");
1136 }
1137
1138 #[test]
1139 fn the_permission_is_the_intersection_with_the_person() {
1140 let scope = scope(K::Implement, Tools);
1141 // The person left the workspace: their agent can do nothing there.
1142 let user = agent(&[], scope.clone());
1143 let decision = decide_operation(
1144 &user,
1145 &scope,
1146 "get_issue",
1147 Some(&path("acme", "rocket")),
1148 true,
1149 Some(1),
1150 );
1151 assert!(!decision.allowed);
1152 assert_eq!(decision.rule, "on-behalf-of:membership");
1153 // And an owner's agent is only ever a member.
1154 let owner = vec![
1155 Membership {
1156 slug: "acme".to_owned(),
1157 role: Role::Owner,
1158 name: None,
1159 avatar: None,
1160 base_permission: Some(BasePermission::None),
1161 team_creation: None,
1162 org_roles: vec![crate::OrgRole::SecurityManager],
1163 privileges: None,
1164 },
1165 Membership::member("elsewhere"),
1166 ];
1167 let memberships = intersect(&owner, "Acme");
1168 assert_eq!(memberships.len(), 1);
1169 assert_eq!(memberships[0].slug, "acme");
1170 assert_eq!(memberships[0].role, Role::Member);
1171 assert!(memberships[0].org_roles.is_empty());
1172 assert!(intersect(&owner, "nowhere").is_empty());
1173 }
1174
1175 /// An agent gets at most the person's role on the repository, and
1176 /// never more than Write; nothing outside the run's workspace.
1177 #[test]
1178 fn an_agent_has_at_most_its_persons_role() {
1179 use crate::access::{Capability, RepoRef, can, permission};
1180 let rocket = RepoRef { id: "rep_1", namespace: "acme", private: true };
1181 let other = RepoRef { id: "rep_2", namespace: "acme", private: true };
1182 let elsewhere = RepoRef { id: "rep_3", namespace: "globex", private: true };
1183 let tools = scope(K::Implement, Tools);
1184 let scope = scope(K::Implement, Runner);
1185 // An owner's agent: Write, never Admin.
1186 let owner = [Membership { role: Role::Owner, ..Membership::member("acme") }, Membership::member("globex")];
1187 let mut agent_user = agent(&[], scope.clone());
1188 agent_user.workspaces = intersect(&owner, "acme");
1189 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Write));
1190 assert!(!can(Some(&agent_user), rocket, Capability::ManageSettings));
1191 assert_eq!(permission(Some(&agent_user), elsewhere), None);
1192 // A member whose workspace gives Read: Read, so it cannot push.
1193 let reader = [Membership { base_permission: Some(BasePermission::Read), ..Membership::member("acme") }];
1194 agent_user.workspaces = intersect(&reader, "acme");
1195 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Read));
1196 assert!(!can(Some(&agent_user), rocket, Capability::Push));
1197 // An outside collaborator with Maintain on one repository: Write
1198 // there, nothing elsewhere, and the run is allowed.
1199 let grants = [
1200 RepoGrant { repo_id: "rep_1".into(), workspace: "acme".into(), role: RepoRole::Maintain, team: None },
1201 RepoGrant { repo_id: "rep_3".into(), workspace: "globex".into(), role: RepoRole::Admin, team: None },
1202 ];
1203 agent_user.workspaces = intersect(&[], "acme");
1204 agent_user.grants = intersect_grants(&grants, "Acme");
1205 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Write));
1206 assert_eq!(permission(Some(&agent_user), other), None);
1207 assert_eq!(permission(Some(&agent_user), elsewhere), None);
1208 let decision = decide_operation(&agent_user, &tools, "get_issue", Some(&path("acme", "rocket")), true, Some(1));
1209 assert!(decision.allowed, "{}", decision.reason.unwrap_or_default());
1210 // The person, downstream of a runner's credential, carries the same.
1211 let person = as_person(&agent_user).expect("a runner acts as the person");
1212 assert_eq!(permission(Some(&person), rocket), Some(RepoRole::Write));
1213 }
1214
1215 #[test]
1216 fn a_runner_changes_only_its_own_pull_request() {
1217 let scope = scope(K::Implement, Runner);
1218 let user = agent(&["acme"], scope.clone());
1219 let repo = path("acme", "rocket");
1220 let other = decide_operation(&user, &scope, "record_session", Some(&repo), true, Some(8));
1221 assert!(!other.allowed);
1222 assert_eq!(other.rule, "scope:pull");
1223 let own = decide_operation(&user, &scope, "record_session", Some(&repo), true, Some(7));
1224 assert!(own.allowed);
1225 // Reading another is fine.
1226 assert!(
1227 decide_operation(
1228 &user,
1229 &scope,
1230 "get_pull_request",
1231 Some(&repo),
1232 true,
1233 Some(8)
1234 )
1235 .allowed
1236 );
1237 }
1238
1239 #[test]
1240 fn git_matrix() {
1241 let fork = path("pulls", "pul_7");
1242 let upstream = path("acme", "rocket");
1243 let elsewhere = path("acme", "billing");
1244 let implement = scope(K::Implement, Runner);
1245 assert!(decide_git(&implement, &fork, true).allowed);
1246 assert!(decide_git(&implement, &fork, false).allowed);
1247 assert!(decide_git(&implement, &upstream, false).allowed);
1248 assert_eq!(decide_git(&implement, &upstream, true).rule, "git:push");
1249 assert_eq!(decide_git(&implement, &elsewhere, false).rule, "git:read");
1250 let review = scope(K::Review, Runner);
1251 assert!(decide_git(&review, &upstream, false).allowed);
1252 assert!(!decide_git(&review, &upstream, true).allowed);
1253 assert!(!decide_git(&review, &fork, true).allowed);
1254 // A tools token made before run credentials never reaches git.
1255 let old = AgentScope {
1256 repo: upstream.clone(),
1257 operations: vec!["get_issue".to_owned()],
1258 run: None,
1259 };
1260 assert_eq!(decide_git(&old, &upstream, false).rule, "git:not-a-run");
1261 // Nor does an agent's tools token.
1262 assert_eq!(
1263 decide_git(&scope(K::Implement, Tools), &upstream, false).rule,
1264 "git:not-a-run"
1265 );
1266 }
1267
1268 #[test]
1269 fn a_push_moves_only_granted_branches() {
1270 let update = scope(K::Update, Runner);
1271 let repo = path("acme", "rocket");
1272 let refs = |names: &[&str]| {
1273 names
1274 .iter()
1275 .map(|name| (*name).to_owned())
1276 .collect::<Vec<_>>()
1277 };
1278 assert!(decide_refs(&update, &repo, &refs(&["refs/heads/fix-login"])).allowed);
1279 assert_eq!(
1280 decide_refs(&update, &repo, &refs(&["refs/heads/main"])).rule,
1281 "git:ref"
1282 );
1283 assert_eq!(
1284 decide_refs(
1285 &update,
1286 &repo,
1287 &refs(&["refs/heads/fix-login", "refs/tags/v1"])
1288 )
1289 .rule,
1290 "git:ref"
1291 );
1292 let implement = scope(K::Implement, Runner);
1293 assert!(
1294 decide_refs(
1295 &implement,
1296 &path("pulls", "pul_7"),
1297 &refs(&["refs/heads/main"])
1298 )
1299 .allowed
1300 );
1301 }
1302
1303 #[test]
1304 fn a_runner_acts_downstream_as_the_person() {
1305 let user = agent(&["acme"], scope(K::Implement, Runner));
1306 let person = as_person(&user).unwrap();
1307 assert_eq!(person.id, "usr_1");
1308 assert_eq!(person.username, "syntaqx");
1309 assert_eq!(person.kind, PrincipalKind::User);
1310 assert!(person.is_member("acme"));
1311 assert!(person.acting.is_none());
1312 assert_eq!(describe(&user), "g1t on behalf of syntaqx");
1313 // The tools act as the agent.
1314 assert!(as_person(&agent(&["acme"], scope(K::Implement, Tools))).is_none());
1315 }
1316
1317 #[test]
1318 fn scopes_without_a_run_still_parse() {
1319 let old: AgentScope = serde_json::from_str(
1320 r#"{"repo":{"namespace":"acme","name":"rocket"},"operations":["get_issue"]}"#,
1321 )
1322 .unwrap();
1323 assert!(old.run.is_none());
1324 let written = serde_json::to_string(&scope(K::Review, Tools)).unwrap();
1325 assert!(written.contains(r#""use":"tools""#));
1326 assert!(written.contains(r#""kind":"review""#));
1327 let back: AgentScope = serde_json::from_str(&written).unwrap();
1328 assert_eq!(back.run.unwrap().kind, K::Review);
1329 // Only g1t's own runs say so; every other reads as not.
1330 assert!(!written.contains("system"));
1331 assert!(!back_run(&written).system);
1332 let mut own = scope(K::Bump, Runner);
1333 own.run.as_mut().unwrap().system = true;
1334 let written = serde_json::to_string(&own).unwrap();
1335 assert!(written.contains(r#""system":true"#));
1336 assert!(back_run(&written).system);
1337 }
1338
1339 fn back_run(written: &str) -> RunBinding {
1340 serde_json::from_str::<AgentScope>(written).unwrap().run.unwrap()
1341 }
1342}