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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_notifications",
311 "get_notification_thread",
312 "get_thread_subscription",
313 "get_repo_subscription",
314 "list_watched_repos",
315 "list_pinned_projects",
316];
317
318/// What no agent's token may ever do, whatever its scope says: workspaces,
319/// repositories' settings, members, tokens, billing, integrations,
320/// webhooks, secrets, workflows' controls, merging, and putting more agents
321/// to work.
322pub const NEVER: &[&str] = &[
323 // Billing is people's: agents never spend or change it.
324 "set_budget",
325 "buy_ai_credit",
326 "create_workspace",
327 "delete_workspace",
328 "update_workspace",
329 // So is who belongs to a workspace and who owns it.
330 "list_members",
331 "update_member",
332 "remove_member",
333 "transfer_ownership",
334 "leave_workspace",
335 "transfer_repo",
336 "create_repo",
337 "update_repo",
338 "update_project",
339 "delete_repo",
340 "list_deleted_repos",
341 "restore_repo",
342 "purge_repo",
343 "rename_repo",
344 "archive_repo",
345 "unarchive_repo",
346 "set_repo_visibility",
347 "rename_branch",
348 "update_repo_settings",
349 "merge_pull_request",
350 "assign_issue",
351 "plan_work",
352 "apply_plan",
353 "import_issue",
354 "list_integrations",
355 "connect_integration",
356 "update_integration",
357 "disconnect_integration",
358 "test_integration",
359 "get_model_routes",
360 "set_model_routes",
361 "list_webhooks",
362 "create_webhook",
363 "update_webhook",
364 "delete_webhook",
365 "ping_webhook",
366 "list_webhook_deliveries",
367 "redeliver_webhook",
368 "dispatch_workflow",
369 "cancel_workflow_run",
370 "rerun_workflow_run",
371 "update_workflow",
372 // Nor lets runs or deployments through, or changes what holds them.
373 "approve_workflow_run",
374 "review_pending_deployments",
375 "update_environment",
376 "delete_environment",
377 "set_workflow_permissions",
378 "set_fork_pr_approval",
379 "set_actions_access",
380 "create_repository_dispatch",
381 "set_workspace_workflow_permissions",
382 // An agent never reports checks on its own work, nor asks for them
383 // to run again: what checks say is the integrations' to say.
384 "create_commit_status",
385 "create_check_run",
386 "update_check_run",
387 "rerequest_check_run",
388 "rerequest_check_suite",
389 "list_actions_secrets",
390 "set_actions_secret",
391 "delete_actions_secret",
392 "list_actions_variables",
393 "set_actions_variable",
394 "delete_actions_variable",
395 "list_collaborators",
396 "get_collaborator_permission",
397 "add_collaborator",
398 "update_collaborator",
399 "remove_collaborator",
400 "list_repo_invitations",
401 "revoke_repo_invitation",
402 "list_my_repo_invitations",
403 "accept_repo_invitation",
404 "decline_repo_invitation",
405 // Nor answers a workspace invitation: only the person it is for does.
406 "accept_invitation",
407 "decline_invitation",
408 "set_base_permission",
409 "list_outside_collaborators",
410 // Deploy keys, which let a machine into a repository.
411 "list_deploy_keys",
412 "get_deploy_key",
413 "create_deploy_key",
414 "delete_deploy_key",
415 // Teams: who is in which, and what they reach, is for people.
416 "create_team",
417 "update_team",
418 "delete_team",
419 "set_team_member",
420 "remove_team_member",
421 "set_team_repo",
422 "remove_team_repo",
423 "set_team_review_assignment",
424 // Dismissing a secret lets it through push protection.
425 "dismiss_security_alert",
426 "reopen_security_alert",
427 // Nor any other decision about security: closing or reopening an
428 // alert, pushing past push protection or deciding who may, changing
429 // what is looked for or when checks fail, or putting more agents to
430 // work. An agent fixes what it finds in its own pull request.
431 "update_secret_scanning_alert",
432 "bypass_push_protection",
433 "review_bypass_request",
434 "create_custom_pattern",
435 "update_custom_pattern",
436 "delete_custom_pattern",
437 "update_code_scanning_alert",
438 "update_vulnerability_alert",
439 "fix_security_alert",
440 "update_security_settings",
441 "update_workspace_security_settings",
442 // A person's own inbox: g1t's agents act as g1t, which has none.
443 "list_notifications",
444 "get_notification_thread",
445 "mark_notifications_read",
446 "mark_thread_read",
447 "mark_thread_done",
448 "save_thread",
449 "snooze_thread",
450 "get_thread_subscription",
451 "set_thread_subscription",
452 "delete_thread_subscription",
453 "get_repo_subscription",
454 "set_repo_subscription",
455 "delete_repo_subscription",
456 "list_watched_repos",
457 // Pins are a person's own, as the inbox is.
458 "list_pinned_projects",
459 "pin_project",
460 "unpin_project",
461 "reorder_pinned_projects",
462 // Deleting packages and deciding who may use them is for people: an
463 // agent publishes its repository's packages and never deletes them.
464 "update_package",
465 "link_package",
466 "unlink_package",
467 "set_package_access",
468 "remove_package_access",
469 "set_package_actions_access",
470 "remove_package_actions_access",
471 "delete_package",
472 "restore_package",
473 "delete_package_version",
474 "restore_package_version",
475];
476
477/// Reading what an agent needs to know about its repository.
478const TOOLS_READ: &[&str] = &[
479 "get_repo",
480 "list_issues",
481 "get_issue",
482 "list_labels",
483 "list_issue_labels",
484 "list_milestones",
485 "get_milestone",
486 "list_pull_requests",
487 "get_pull_request",
488 "get_pull_request_changes",
489 "read_session",
490 "get_merge_queue",
491 "list_events",
492 "recall",
493 "search_context",
494 "get_entity",
495 "search",
496 "list_workflows",
497 "list_workflow_runs",
498 "get_workflow_run",
499 "get_job_logs",
500 "get_pending_deployments",
501 "get_workflow_permissions",
502 "get_fork_pr_approval",
503 "list_commit_statuses",
504 "get_combined_status",
505 "list_check_runs_for_ref",
506 "get_check_run",
507 "list_check_run_annotations",
508 "list_check_suites_for_ref",
509 "get_check_suite",
510];
511
512pub fn is_read(operation: &str) -> bool {
513 READ_OPERATIONS.contains(&operation)
514}
515
516/// The API and MCP operations a run of `kind` may use with a credential
517/// for `usage`. Git is separate: see [`decide_git`].
518pub fn operations_for(kind: RunCredentialKind, usage: CredentialUse) -> Vec<&'static str> {
519 use RunCredentialKind as K;
520 let mut operations: Vec<&'static str> = Vec::new();
521 match usage {
522 CredentialUse::Runner => {
523 if kind.works_on_a_pull() {
524 operations.extend(["get_repo", "get_pull_request", "record_session"]);
525 }
526 if kind == K::Implement {
527 operations.push("mark_pull_request_ready");
528 }
529 }
530 CredentialUse::Tools => match kind {
531 K::Implement | K::Revise | K::Answer => {
532 operations.extend(TOOLS_READ.iter().copied());
533 operations.extend([
534 "create_issue",
535 "add_comment",
536 "take_messages",
537 "remember",
538 "message_agent",
539 "answer_message",
540 "get_context",
541 ]);
542 }
543 K::Review => {
544 operations.extend(TOOLS_READ.iter().copied());
545 operations.extend(["add_comment", "review_pull_request", "get_context"]);
546 }
547 K::Plan => {
548 operations.extend(TOOLS_READ.iter().copied());
549 operations.extend(["create_issue", "get_context"]);
550 }
551 K::Update => operations.extend(TOOLS_READ.iter().copied()),
552 K::Checks | K::Queue | K::Mergecheck | K::Deploy | K::Bump => {}
553 },
554 }
555 operations
556}
557
558/// What a run's credential may do, in the scope vocabulary that access
559/// tokens use (see [`crate::scopes`]): the scopes of its operations, and
560/// for a runner, git's. Its operations, its repository and its run still
561/// bound it more tightly than these scopes say.
562pub fn run_scopes(kind: RunCredentialKind, usage: CredentialUse) -> Vec<crate::scopes::Scope> {
563 use crate::scopes::{Scope, normalize, scope_for};
564 let mut scopes: Vec<Scope> = operations_for(kind, usage)
565 .into_iter()
566 .filter_map(scope_for)
567 .collect();
568 if usage == CredentialUse::Runner {
569 scopes.push(Scope::CodeRead);
570 if matches!(
571 kind,
572 RunCredentialKind::Implement
573 | RunCredentialKind::Revise
574 | RunCredentialKind::Answer
575 | RunCredentialKind::Update
576 | RunCredentialKind::Bump
577 ) {
578 scopes.push(Scope::CodeWrite);
579 }
580 }
581 normalize(&mut scopes);
582 scopes
583}
584
585/// Operations that change a pull request, which a runner may do only to
586/// the pull request its run works on.
587const PULL_WRITES: &[&str] = &["record_session", "mark_pull_request_ready"];
588
589/// Whether something was allowed, and the rule that decided it.
590#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
591pub struct Decision {
592 pub allowed: bool,
593 /// A short, stable name: `run:implement/tools`, `never`,
594 /// `scope:repository` and so on. Shown in the audit log.
595 pub rule: String,
596 /// Why it was refused, for the caller.
597 #[serde(default, skip_serializing_if = "Option::is_none")]
598 pub reason: Option<String>,
599}
600
601impl Decision {
602 pub fn allow(rule: impl Into<String>) -> Self {
603 Decision {
604 allowed: true,
605 rule: rule.into(),
606 reason: None,
607 }
608 }
609
610 pub fn deny(rule: impl Into<String>, reason: impl Into<String>) -> Self {
611 Decision {
612 allowed: false,
613 rule: rule.into(),
614 reason: Some(reason.into()),
615 }
616 }
617}
618
619fn same_repo(a: &RepoPath, b: &RepoPath) -> bool {
620 a.namespace.eq_ignore_ascii_case(&b.namespace) && a.name.eq_ignore_ascii_case(&b.name)
621}
622
623fn scope_rule(scope: &AgentScope) -> String {
624 match &scope.run {
625 Some(run) => format!("run:{}/{}", run.kind.as_str(), run.usage.as_str()),
626 None => "agent-token".to_owned(),
627 }
628}
629
630/// Whether `user`, resolved from an agent's token with `scope`, may use
631/// `operation`. `repo` is the repository the call names, if any, and
632/// `needs_repo` whether the operation is about one; `number` the issue or
633/// pull request it names.
634pub fn decide_operation(
635 user: &User,
636 scope: &AgentScope,
637 operation: &str,
638 repo: Option<&RepoPath>,
639 needs_repo: bool,
640 number: Option<u32>,
641) -> Decision {
642 let who = "A g1t agent's token";
643 if NEVER.contains(&operation) {
644 return Decision::deny(
645 "never",
646 format!(
647 "{who} can never use {operation}: settings, members, tokens, billing, integrations, webhooks, secrets and merging are for people."
648 ),
649 );
650 }
651 if !scope.operations.iter().any(|name| name == operation) {
652 return Decision::deny(
653 "scope:operation",
654 format!("{who} for this run cannot use {operation}."),
655 );
656 }
657 if needs_repo && !repo.is_some_and(|asked| same_repo(asked, &scope.repo)) {
658 return Decision::deny(
659 "scope:repository",
660 format!(
661 "{who} works in {}/{} only.",
662 scope.repo.namespace, scope.repo.name
663 ),
664 );
665 }
666 // The intersection: the person it acts for must still be able to work
667 // in the repository's workspace, as a member or with a role on its
668 // repositories. What it may do in the repository itself is their
669 // role there, which services check (`access::can`).
670 if !crate::access::has_access_in(user, &scope.repo.namespace) {
671 return Decision::deny(
672 "on-behalf-of:membership",
673 format!(
674 "The person this agent works for is no longer a member of {}.",
675 scope.repo.namespace
676 ),
677 );
678 }
679 if let Some(run) = &scope.run
680 && run.usage == CredentialUse::Runner
681 && PULL_WRITES.contains(&operation)
682 && run.number.is_some()
683 && number != run.number
684 {
685 return Decision::deny(
686 "scope:pull",
687 format!(
688 "{who} can change pull request #{} only.",
689 run.number.unwrap_or_default()
690 ),
691 );
692 }
693 Decision::allow(scope_rule(scope))
694}
695
696/// Whether a run credential may clone or fetch (`write` false), or push to
697/// (`write` true), the repository at `repo`.
698pub fn decide_git(scope: &AgentScope, repo: &RepoPath, write: bool) -> Decision {
699 let Some(run) = scope
700 .run
701 .as_ref()
702 .filter(|run| run.usage == CredentialUse::Runner)
703 else {
704 return Decision::deny(
705 "git:not-a-run",
706 "A g1t agent's tools token cannot be used with git.",
707 );
708 };
709 let pushable = run.push.iter().any(|grant| same_repo(&grant.repo, repo));
710 if write {
711 return if pushable {
712 Decision::allow(format!("{}:push", scope_rule(scope)))
713 } else {
714 Decision::deny(
715 "git:push",
716 format!(
717 "A {} run cannot push to {}/{}.",
718 run.kind.as_str(),
719 repo.namespace,
720 repo.name
721 ),
722 )
723 };
724 }
725 let readable = pushable
726 || same_repo(&scope.repo, repo)
727 || run.read.iter().any(|path| same_repo(path, repo));
728 if readable {
729 Decision::allow(format!("{}:read", scope_rule(scope)))
730 } else {
731 Decision::deny(
732 "git:read",
733 format!(
734 "A {} run cannot read {}/{}.",
735 run.kind.as_str(),
736 repo.namespace,
737 repo.name
738 ),
739 )
740 }
741}
742
743/// Whether a push to `repo` is limited to certain branches, so that the
744/// refs it moves have to be read and checked with [`decide_refs`].
745pub fn limits_branches(scope: &AgentScope, repo: &RepoPath) -> bool {
746 scope
747 .run
748 .iter()
749 .flat_map(|run| run.push.iter())
750 .any(|grant| same_repo(&grant.repo, repo) && grant.branch.is_some())
751}
752
753/// Whether a push to `repo` may move `refs` (full refs, such as
754/// `refs/heads/main`). Tags are never a run's to move.
755pub fn decide_refs(scope: &AgentScope, repo: &RepoPath, refs: &[String]) -> Decision {
756 let repo_decision = decide_git(scope, repo, true);
757 if !repo_decision.allowed {
758 return repo_decision;
759 }
760 let grants: Vec<&GitGrant> = scope
761 .run
762 .iter()
763 .flat_map(|run| run.push.iter())
764 .filter(|grant| same_repo(&grant.repo, repo))
765 .collect();
766 for git_ref in refs {
767 let Some(branch) = git_ref.strip_prefix("refs/heads/") else {
768 return Decision::deny("git:ref", format!("A run cannot push {git_ref}."));
769 };
770 let allowed = grants
771 .iter()
772 .any(|grant| grant.branch.as_deref().is_none_or(|only| only == branch));
773 if !allowed {
774 return Decision::deny(
775 "git:ref",
776 format!(
777 "A run cannot push to {branch} in {}/{}.",
778 repo.namespace, repo.name
779 ),
780 );
781 }
782 }
783 repo_decision
784}
785
786/// The most an agent may be on a repository, whoever it works for: it
787/// can push, merge and run, never change settings or who has access.
788pub const AGENT_CEILING: RepoRole = RepoRole::Write;
789
790/// The memberships an agent working for `person` has: the run's
791/// workspace, as a member, only if the person is in it now, with the
792/// person's role on its repositories (an owner's Admin included) cut down
793/// to [`AGENT_CEILING`].
794pub fn intersect(person: &[Membership], namespace: &str) -> Vec<Membership> {
795 let namespace = namespace.to_lowercase();
796 person
797 .iter()
798 .filter(|membership| membership.slug == namespace)
799 .map(|membership| {
800 let base = match membership.role {
801 Role::Owner => BasePermission::Admin,
802 Role::Member => membership.base_permission.unwrap_or_default(),
803 };
804 Membership {
805 role: Role::Member,
806 base_permission: Some(match base {
807 BasePermission::Admin => BasePermission::Write,
808 base => base,
809 }),
810 // Billing and security manager are the person's, never
811 // their agent's.
812 org_roles: Vec::new(),
813 ..membership.clone()
814 }
815 })
816 .collect()
817}
818
819/// The repository grants an agent working for `person` has: those in the
820/// run's workspace, each cut down to [`AGENT_CEILING`].
821pub fn intersect_grants(person: &[RepoGrant], namespace: &str) -> Vec<RepoGrant> {
822 let namespace = namespace.to_lowercase();
823 person
824 .iter()
825 .filter(|grant| grant.workspace == namespace)
826 .map(|grant| RepoGrant {
827 role: grant.role.min(AGENT_CEILING),
828 ..grant.clone()
829 })
830 .collect()
831}
832
833/// Who a runner's credential acts as downstream: the person, with only the
834/// agent's (already intersected) memberships. `None` for anything else.
835pub fn as_person(user: &User) -> Option<User> {
836 let acting = user.acting.as_ref()?;
837 if user.kind != PrincipalKind::Agent {
838 return None;
839 }
840 let run = acting.run()?;
841 if run.usage != CredentialUse::Runner {
842 return None;
843 }
844 Some(User {
845 id: acting.on_behalf_of.id.clone(),
846 username: acting.on_behalf_of.username.clone(),
847 display_username: None,
848 kind: PrincipalKind::User,
849 verified: user.verified,
850 workspaces: user.workspaces.clone(),
851 avatar: None,
852 acting: None,
853 grants: user.grants.clone(),
854 token: None,
855 held: Vec::new(),
856 })
857}
858
859/// How an actor is described: "g1t on behalf of syntaqx".
860pub fn describe(user: &User) -> String {
861 match &user.acting {
862 Some(acting) => format!(
863 "{} on behalf of {}",
864 acting.agent, acting.on_behalf_of.username
865 ),
866 None => user.username.clone(),
867 }
868}
869
870#[cfg(test)]
871mod tests {
872 use super::*;
873
874 #[test]
875 fn a_run_s_scopes_are_never_admin() {
876 for kind in RunCredentialKind::ALL {
877 for usage in [CredentialUse::Runner, CredentialUse::Tools] {
878 let scopes = run_scopes(kind, usage);
879 assert!(scopes.iter().all(|scope| !scope.dangerous()), "{kind:?} {usage:?}: {scopes:?}");
880 }
881 }
882 let review = run_scopes(RunCredentialKind::Review, CredentialUse::Tools);
883 assert!(review.contains(&crate::scopes::Scope::PullRequestsWrite));
884 assert!(!review.contains(&crate::scopes::Scope::CodeWrite));
885 }
886
887 #[test]
888 fn agents_can_search_the_context_hub() {
889 for kind in [RunCredentialKind::Implement, RunCredentialKind::Review, RunCredentialKind::Plan] {
890 let tools = operations_for(kind, CredentialUse::Tools);
891 assert!(tools.contains(&"search_context") && tools.contains(&"get_entity"));
892 }
893 assert!(is_read("search_context") && is_read("get_entity"));
894 }
895
896 #[test]
897 fn agents_can_search_all_of_g1t() {
898 // Site-wide search only reads: every run that reads its repository
899 // may use it, and nothing that never reads gets it.
900 assert!(is_read("search"));
901 assert!(!NEVER.contains(&"search"));
902 for kind in [
903 RunCredentialKind::Implement,
904 RunCredentialKind::Revise,
905 RunCredentialKind::Answer,
906 RunCredentialKind::Review,
907 RunCredentialKind::Plan,
908 RunCredentialKind::Update,
909 ] {
910 let tools = operations_for(kind, CredentialUse::Tools);
911 assert!(tools.contains(&"search"), "{kind:?} should search");
912 // The context hub's search stays its own tool beside it.
913 assert!(tools.contains(&"search_context"), "{kind:?} keeps search_context");
914 }
915 for kind in [RunCredentialKind::Checks, RunCredentialKind::Queue, RunCredentialKind::Mergecheck, RunCredentialKind::Deploy, RunCredentialKind::Bump] {
916 assert!(!operations_for(kind, CredentialUse::Tools).contains(&"search"));
917 }
918 assert!(!operations_for(RunCredentialKind::Implement, CredentialUse::Runner).contains(&"search"));
919 }
920
921 fn path(namespace: &str, name: &str) -> RepoPath {
922 RepoPath {
923 namespace: namespace.to_owned(),
924 name: name.to_owned(),
925 }
926 }
927
928 fn scope(kind: RunCredentialKind, usage: CredentialUse) -> AgentScope {
929 AgentScope {
930 repo: path("acme", "rocket"),
931 operations: operations_for(kind, usage)
932 .into_iter()
933 .map(str::to_owned)
934 .collect(),
935 run: Some(RunBinding {
936 kind,
937 usage,
938 run_id: Some("run_1".to_owned()),
939 number: Some(7),
940 agent: "g1t".to_owned(),
941 system: false,
942 read: vec![path("acme", "rocket")],
943 push: match kind {
944 RunCredentialKind::Implement
945 | RunCredentialKind::Revise
946 | RunCredentialKind::Answer => vec![GitGrant {
947 repo: path("pulls", "pul_7"),
948 branch: None,
949 }],
950 RunCredentialKind::Update => vec![GitGrant {
951 repo: path("acme", "rocket"),
952 branch: Some("fix-login".to_owned()),
953 }],
954 _ => vec![],
955 },
956 }),
957 }
958 }
959
960 fn agent(member_of: &[&str], scope: AgentScope) -> User {
961 User {
962 id: "usr_g1t_agent".to_owned(),
963 username: "g1t".to_owned(),
964 display_username: None,
965 kind: PrincipalKind::Agent,
966 verified: true,
967 workspaces: member_of
968 .iter()
969 .map(|slug| Membership::member(*slug))
970 .collect(),
971 avatar: None,
972 grants: Vec::new(),
973 token: None,
974 held: Vec::new(),
975 acting: Some(Box::new(Acting {
976 credential_id: "tok_1".to_owned(),
977 agent: "g1t".to_owned(),
978 on_behalf_of: Principal {
979 id: "usr_1".to_owned(),
980 username: "syntaqx".to_owned(),
981 },
982 scope,
983 })),
984 }
985 }
986
987 fn op(kind: RunCredentialKind, usage: CredentialUse, operation: &str) -> Decision {
988 let scope = scope(kind, usage);
989 let user = agent(&["acme"], scope.clone());
990 decide_operation(
991 &user,
992 &scope,
993 operation,
994 Some(&path("acme", "rocket")),
995 true,
996 Some(7),
997 )
998 }
999
1000 use CredentialUse::{Runner, Tools};
1001 use RunCredentialKind as K;
1002
1003 /// Which operations each kind of run may use through its tools: the
1004 /// allowed and denied matrix.
1005 #[test]
1006 fn tools_matrix() {
1007 let cases: [(&str, [bool; 6]); 12] = [
1008 // implement revise answer review plan checks
1009 ("get_issue", [true, true, true, true, true, false]),
1010 ("create_issue", [true, true, true, false, true, false]),
1011 ("add_comment", [true, true, true, true, false, false]),
1012 (
1013 "review_pull_request",
1014 [false, false, false, true, false, false],
1015 ),
1016 ("remember", [true, true, true, false, false, false]),
1017 ("take_messages", [true, true, true, false, false, false]),
1018 ("record_session", [false, false, false, false, false, false]),
1019 (
1020 "merge_pull_request",
1021 [false, false, false, false, false, false],
1022 ),
1023 (
1024 "update_repo_settings",
1025 [false, false, false, false, false, false],
1026 ),
1027 ("create_webhook", [false, false, false, false, false, false]),
1028 (
1029 "set_actions_secret",
1030 [false, false, false, false, false, false],
1031 ),
1032 ("assign_issue", [false, false, false, false, false, false]),
1033 ];
1034 let kinds = [
1035 K::Implement,
1036 K::Revise,
1037 K::Answer,
1038 K::Review,
1039 K::Plan,
1040 K::Checks,
1041 ];
1042 for (operation, expected) in cases {
1043 for (kind, allowed) in kinds.into_iter().zip(expected) {
1044 assert_eq!(
1045 op(kind, Tools, operation).allowed,
1046 allowed,
1047 "{operation} by a {} run's tools",
1048 kind.as_str()
1049 );
1050 }
1051 }
1052 }
1053
1054 #[test]
1055 fn runner_matrix() {
1056 assert!(op(K::Implement, Runner, "record_session").allowed);
1057 assert!(op(K::Implement, Runner, "mark_pull_request_ready").allowed);
1058 assert!(op(K::Revise, Runner, "record_session").allowed);
1059 assert!(!op(K::Revise, Runner, "mark_pull_request_ready").allowed);
1060 assert!(!op(K::Implement, Runner, "create_issue").allowed);
1061 assert!(!op(K::Review, Runner, "record_session").allowed);
1062 assert!(!op(K::Checks, Runner, "get_issue").allowed);
1063 }
1064
1065 #[test]
1066 fn settings_billing_tokens_and_members_are_never_reachable() {
1067 for kind in RunCredentialKind::ALL {
1068 for usage in [Runner, Tools] {
1069 for operation in NEVER.iter().copied() {
1070 let decision = op(kind, usage, operation);
1071 assert!(!decision.allowed);
1072 assert_eq!(decision.rule, "never");
1073 }
1074 }
1075 }
1076 // Even a scope that lists one is refused.
1077 let mut wide = scope(K::Implement, Tools);
1078 wide.operations.push("merge_pull_request".to_owned());
1079 let user = agent(&["acme"], wide.clone());
1080 let decision = decide_operation(
1081 &user,
1082 &wide,
1083 "merge_pull_request",
1084 Some(&path("acme", "rocket")),
1085 true,
1086 Some(7),
1087 );
1088 assert_eq!(decision.rule, "never");
1089 }
1090
1091 #[test]
1092 fn another_repository_is_refused() {
1093 let scope = scope(K::Implement, Tools);
1094 let user = agent(&["acme"], scope.clone());
1095 let decision = decide_operation(
1096 &user,
1097 &scope,
1098 "create_issue",
1099 Some(&path("acme", "other")),
1100 true,
1101 None,
1102 );
1103 assert!(!decision.allowed);
1104 assert_eq!(decision.rule, "scope:repository");
1105 let decision = decide_operation(&user, &scope, "create_issue", None, true, None);
1106 assert_eq!(decision.rule, "scope:repository");
1107 // The repository's name is matched without regard to case.
1108 let decision = decide_operation(
1109 &user,
1110 &scope,
1111 "create_issue",
1112 Some(&path("Acme", "Rocket")),
1113 true,
1114 None,
1115 );
1116 assert!(decision.allowed);
1117 assert_eq!(decision.rule, "run:implement/tools");
1118 }
1119
1120 #[test]
1121 fn the_permission_is_the_intersection_with_the_person() {
1122 let scope = scope(K::Implement, Tools);
1123 // The person left the workspace: their agent can do nothing there.
1124 let user = agent(&[], scope.clone());
1125 let decision = decide_operation(
1126 &user,
1127 &scope,
1128 "get_issue",
1129 Some(&path("acme", "rocket")),
1130 true,
1131 Some(1),
1132 );
1133 assert!(!decision.allowed);
1134 assert_eq!(decision.rule, "on-behalf-of:membership");
1135 // And an owner's agent is only ever a member.
1136 let owner = vec![
1137 Membership {
1138 slug: "acme".to_owned(),
1139 role: Role::Owner,
1140 name: None,
1141 avatar: None,
1142 base_permission: Some(BasePermission::None),
1143 team_creation: None,
1144 org_roles: vec![crate::OrgRole::SecurityManager],
1145 privileges: None,
1146 },
1147 Membership::member("elsewhere"),
1148 ];
1149 let memberships = intersect(&owner, "Acme");
1150 assert_eq!(memberships.len(), 1);
1151 assert_eq!(memberships[0].slug, "acme");
1152 assert_eq!(memberships[0].role, Role::Member);
1153 assert!(memberships[0].org_roles.is_empty());
1154 assert!(intersect(&owner, "nowhere").is_empty());
1155 }
1156
1157 /// An agent gets at most the person's role on the repository, and
1158 /// never more than Write; nothing outside the run's workspace.
1159 #[test]
1160 fn an_agent_has_at_most_its_persons_role() {
1161 use crate::access::{Capability, RepoRef, can, permission};
1162 let rocket = RepoRef { id: "rep_1", namespace: "acme", private: true };
1163 let other = RepoRef { id: "rep_2", namespace: "acme", private: true };
1164 let elsewhere = RepoRef { id: "rep_3", namespace: "globex", private: true };
1165 let tools = scope(K::Implement, Tools);
1166 let scope = scope(K::Implement, Runner);
1167 // An owner's agent: Write, never Admin.
1168 let owner = [Membership { role: Role::Owner, ..Membership::member("acme") }, Membership::member("globex")];
1169 let mut agent_user = agent(&[], scope.clone());
1170 agent_user.workspaces = intersect(&owner, "acme");
1171 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Write));
1172 assert!(!can(Some(&agent_user), rocket, Capability::ManageSettings));
1173 assert_eq!(permission(Some(&agent_user), elsewhere), None);
1174 // A member whose workspace gives Read: Read, so it cannot push.
1175 let reader = [Membership { base_permission: Some(BasePermission::Read), ..Membership::member("acme") }];
1176 agent_user.workspaces = intersect(&reader, "acme");
1177 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Read));
1178 assert!(!can(Some(&agent_user), rocket, Capability::Push));
1179 // An outside collaborator with Maintain on one repository: Write
1180 // there, nothing elsewhere, and the run is allowed.
1181 let grants = [
1182 RepoGrant { repo_id: "rep_1".into(), workspace: "acme".into(), role: RepoRole::Maintain, team: None },
1183 RepoGrant { repo_id: "rep_3".into(), workspace: "globex".into(), role: RepoRole::Admin, team: None },
1184 ];
1185 agent_user.workspaces = intersect(&[], "acme");
1186 agent_user.grants = intersect_grants(&grants, "Acme");
1187 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Write));
1188 assert_eq!(permission(Some(&agent_user), other), None);
1189 assert_eq!(permission(Some(&agent_user), elsewhere), None);
1190 let decision = decide_operation(&agent_user, &tools, "get_issue", Some(&path("acme", "rocket")), true, Some(1));
1191 assert!(decision.allowed, "{}", decision.reason.unwrap_or_default());
1192 // The person, downstream of a runner's credential, carries the same.
1193 let person = as_person(&agent_user).expect("a runner acts as the person");
1194 assert_eq!(permission(Some(&person), rocket), Some(RepoRole::Write));
1195 }
1196
1197 #[test]
1198 fn a_runner_changes_only_its_own_pull_request() {
1199 let scope = scope(K::Implement, Runner);
1200 let user = agent(&["acme"], scope.clone());
1201 let repo = path("acme", "rocket");
1202 let other = decide_operation(&user, &scope, "record_session", Some(&repo), true, Some(8));
1203 assert!(!other.allowed);
1204 assert_eq!(other.rule, "scope:pull");
1205 let own = decide_operation(&user, &scope, "record_session", Some(&repo), true, Some(7));
1206 assert!(own.allowed);
1207 // Reading another is fine.
1208 assert!(
1209 decide_operation(
1210 &user,
1211 &scope,
1212 "get_pull_request",
1213 Some(&repo),
1214 true,
1215 Some(8)
1216 )
1217 .allowed
1218 );
1219 }
1220
1221 #[test]
1222 fn git_matrix() {
1223 let fork = path("pulls", "pul_7");
1224 let upstream = path("acme", "rocket");
1225 let elsewhere = path("acme", "billing");
1226 let implement = scope(K::Implement, Runner);
1227 assert!(decide_git(&implement, &fork, true).allowed);
1228 assert!(decide_git(&implement, &fork, false).allowed);
1229 assert!(decide_git(&implement, &upstream, false).allowed);
1230 assert_eq!(decide_git(&implement, &upstream, true).rule, "git:push");
1231 assert_eq!(decide_git(&implement, &elsewhere, false).rule, "git:read");
1232 let review = scope(K::Review, Runner);
1233 assert!(decide_git(&review, &upstream, false).allowed);
1234 assert!(!decide_git(&review, &upstream, true).allowed);
1235 assert!(!decide_git(&review, &fork, true).allowed);
1236 // A tools token made before run credentials never reaches git.
1237 let old = AgentScope {
1238 repo: upstream.clone(),
1239 operations: vec!["get_issue".to_owned()],
1240 run: None,
1241 };
1242 assert_eq!(decide_git(&old, &upstream, false).rule, "git:not-a-run");
1243 // Nor does an agent's tools token.
1244 assert_eq!(
1245 decide_git(&scope(K::Implement, Tools), &upstream, false).rule,
1246 "git:not-a-run"
1247 );
1248 }
1249
1250 #[test]
1251 fn a_push_moves_only_granted_branches() {
1252 let update = scope(K::Update, Runner);
1253 let repo = path("acme", "rocket");
1254 let refs = |names: &[&str]| {
1255 names
1256 .iter()
1257 .map(|name| (*name).to_owned())
1258 .collect::<Vec<_>>()
1259 };
1260 assert!(decide_refs(&update, &repo, &refs(&["refs/heads/fix-login"])).allowed);
1261 assert_eq!(
1262 decide_refs(&update, &repo, &refs(&["refs/heads/main"])).rule,
1263 "git:ref"
1264 );
1265 assert_eq!(
1266 decide_refs(
1267 &update,
1268 &repo,
1269 &refs(&["refs/heads/fix-login", "refs/tags/v1"])
1270 )
1271 .rule,
1272 "git:ref"
1273 );
1274 let implement = scope(K::Implement, Runner);
1275 assert!(
1276 decide_refs(
1277 &implement,
1278 &path("pulls", "pul_7"),
1279 &refs(&["refs/heads/main"])
1280 )
1281 .allowed
1282 );
1283 }
1284
1285 #[test]
1286 fn a_runner_acts_downstream_as_the_person() {
1287 let user = agent(&["acme"], scope(K::Implement, Runner));
1288 let person = as_person(&user).unwrap();
1289 assert_eq!(person.id, "usr_1");
1290 assert_eq!(person.username, "syntaqx");
1291 assert_eq!(person.kind, PrincipalKind::User);
1292 assert!(person.is_member("acme"));
1293 assert!(person.acting.is_none());
1294 assert_eq!(describe(&user), "g1t on behalf of syntaqx");
1295 // The tools act as the agent.
1296 assert!(as_person(&agent(&["acme"], scope(K::Implement, Tools))).is_none());
1297 }
1298
1299 #[test]
1300 fn scopes_without_a_run_still_parse() {
1301 let old: AgentScope = serde_json::from_str(
1302 r#"{"repo":{"namespace":"acme","name":"rocket"},"operations":["get_issue"]}"#,
1303 )
1304 .unwrap();
1305 assert!(old.run.is_none());
1306 let written = serde_json::to_string(&scope(K::Review, Tools)).unwrap();
1307 assert!(written.contains(r#""use":"tools""#));
1308 assert!(written.contains(r#""kind":"review""#));
1309 let back: AgentScope = serde_json::from_str(&written).unwrap();
1310 assert_eq!(back.run.unwrap().kind, K::Review);
1311 // Only g1t's own runs say so; every other reads as not.
1312 assert!(!written.contains("system"));
1313 assert!(!back_run(&written).system);
1314 let mut own = scope(K::Bump, Runner);
1315 own.run.as_mut().unwrap().system = true;
1316 let written = serde_json::to_string(&own).unwrap();
1317 assert!(written.contains(r#""system":true"#));
1318 assert!(back_run(&written).system);
1319 }
1320
1321 fn back_run(written: &str) -> RunBinding {
1322 serde_json::from_str::<AgentScope>(written).unwrap().run.unwrap()
1323 }
1324}