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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 "delete_branch",
352 "update_repo_settings",
353 "merge_pull_request",
354 "assign_issue",
355 "plan_work",
356 "apply_plan",
357 "import_issue",
358 "list_integrations",
359 "connect_integration",
360 "update_integration",
361 "disconnect_integration",
362 "test_integration",
363 "get_model_routes",
364 "set_model_routes",
365 "list_webhooks",
366 "create_webhook",
367 "update_webhook",
368 "delete_webhook",
369 "ping_webhook",
370 "list_webhook_deliveries",
371 "redeliver_webhook",
372 "dispatch_workflow",
373 "cancel_workflow_run",
374 "rerun_workflow_run",
375 "update_workflow",
376 // Nor lets runs or deployments through, or changes what holds them.
377 "approve_workflow_run",
378 "review_pending_deployments",
379 "update_environment",
380 "delete_environment",
381 "set_workflow_permissions",
382 "set_fork_pr_approval",
383 "set_actions_access",
384 "create_repository_dispatch",
385 "set_workspace_workflow_permissions",
386 // An agent never reports checks on its own work, nor asks for them
387 // to run again: what checks say is the integrations' to say.
388 "create_commit_status",
389 "create_check_run",
390 "update_check_run",
391 "rerequest_check_run",
392 "rerequest_check_suite",
393 "list_actions_secrets",
394 "set_actions_secret",
395 "delete_actions_secret",
396 "list_actions_variables",
397 "set_actions_variable",
398 "delete_actions_variable",
399 "list_collaborators",
400 "get_collaborator_permission",
401 "add_collaborator",
402 "update_collaborator",
403 "remove_collaborator",
404 "list_repo_invitations",
405 "revoke_repo_invitation",
406 "list_my_repo_invitations",
407 "accept_repo_invitation",
408 "decline_repo_invitation",
409 // Nor answers a workspace invitation: only the person it is for does.
410 "accept_invitation",
411 "decline_invitation",
412 "set_base_permission",
413 "list_outside_collaborators",
414 // Deploy keys, which let a machine into a repository.
415 "list_deploy_keys",
416 "get_deploy_key",
417 "create_deploy_key",
418 "delete_deploy_key",
419 // Teams: who is in which, and what they reach, is for people.
420 "create_team",
421 "update_team",
422 "delete_team",
423 "set_team_member",
424 "remove_team_member",
425 "set_team_repo",
426 "remove_team_repo",
427 "set_team_review_assignment",
428 // Dismissing a secret lets it through push protection.
429 "dismiss_security_alert",
430 "reopen_security_alert",
431 // Nor any other decision about security: closing or reopening an
432 // alert, pushing past push protection or deciding who may, changing
433 // what is looked for or when checks fail, or putting more agents to
434 // work. An agent fixes what it finds in its own pull request.
435 "update_secret_scanning_alert",
436 "bypass_push_protection",
437 "review_bypass_request",
438 "create_custom_pattern",
439 "update_custom_pattern",
440 "delete_custom_pattern",
441 "update_code_scanning_alert",
442 "update_vulnerability_alert",
443 "fix_security_alert",
444 "update_security_settings",
445 "update_workspace_security_settings",
446 // A person's own inbox: g1t's agents act as g1t, which has none.
447 "list_notifications",
448 "get_notification_thread",
449 "mark_notifications_read",
450 "mark_thread_read",
451 "mark_thread_done",
452 "save_thread",
453 "snooze_thread",
454 "get_thread_subscription",
455 "set_thread_subscription",
456 "delete_thread_subscription",
457 "get_repo_subscription",
458 "set_repo_subscription",
459 "delete_repo_subscription",
460 "list_watched_repos",
461 // Pins are a person's own, as the inbox is.
462 "list_pinned_projects",
463 "pin_project",
464 "unpin_project",
465 "reorder_pinned_projects",
466 // Deleting packages and deciding who may use them is for people: an
467 // agent publishes its repository's packages and never deletes them.
468 "update_package",
469 "link_package",
470 "unlink_package",
471 "set_package_access",
472 "remove_package_access",
473 "set_package_actions_access",
474 "remove_package_actions_access",
475 "delete_package",
476 "restore_package",
477 "delete_package_version",
478 "restore_package_version",
479 // Sharing an artifact and deleting one for good are for people: an
480 // agent shares only through the agents service, with the people
481 // already in its conversation.
482 "set_workspace_artifact_access",
483 "purge_workspace_artifact",
484];
485
486/// Reading what an agent needs to know about its repository.
487const TOOLS_READ: &[&str] = &[
488 "get_repo",
489 "list_issues",
490 "get_issue",
491 "list_labels",
492 "list_issue_labels",
493 "list_milestones",
494 "get_milestone",
495 "list_pull_requests",
496 "get_pull_request",
497 "get_pull_request_changes",
498 "read_session",
499 "get_merge_queue",
500 "list_events",
501 "recall",
502 "search_context",
503 "get_entity",
504 "search",
505 "list_workflows",
506 "list_workflow_runs",
507 "get_workflow_run",
508 "get_job_logs",
509 "get_pending_deployments",
510 "get_workflow_permissions",
511 "get_fork_pr_approval",
512 "list_commit_statuses",
513 "get_combined_status",
514 "list_check_runs_for_ref",
515 "get_check_run",
516 "list_check_run_annotations",
517 "list_check_suites_for_ref",
518 "get_check_suite",
519];
520
521pub fn is_read(operation: &str) -> bool {
522 READ_OPERATIONS.contains(&operation)
523}
524
525/// The API and MCP operations a run of `kind` may use with a credential
526/// for `usage`. Git is separate: see [`decide_git`].
527pub fn operations_for(kind: RunCredentialKind, usage: CredentialUse) -> Vec<&'static str> {
528 use RunCredentialKind as K;
529 let mut operations: Vec<&'static str> = Vec::new();
530 match usage {
531 CredentialUse::Runner => {
532 if kind.works_on_a_pull() {
533 operations.extend(["get_repo", "get_pull_request", "record_session"]);
534 }
535 if kind == K::Implement {
536 operations.push("mark_pull_request_ready");
537 }
538 }
539 CredentialUse::Tools => match kind {
540 K::Implement | K::Revise | K::Answer => {
541 operations.extend(TOOLS_READ.iter().copied());
542 operations.extend([
543 "create_issue",
544 "add_comment",
545 "take_messages",
546 "remember",
547 "message_agent",
548 "answer_message",
549 "get_context",
550 "customize_bundle",
551 ]);
552 }
553 K::Review => {
554 operations.extend(TOOLS_READ.iter().copied());
555 operations.extend(["add_comment", "review_pull_request", "get_context", "customize_bundle"]);
556 }
557 K::Plan => {
558 operations.extend(TOOLS_READ.iter().copied());
559 operations.extend(["create_issue", "get_context", "customize_bundle"]);
560 }
561 K::Update => {
562 operations.extend(TOOLS_READ.iter().copied());
563 operations.push("customize_bundle");
564 }
565 K::Checks | K::Queue | K::Mergecheck | K::Deploy | K::Bump => {}
566 },
567 }
568 operations
569}
570
571/// What a run's credential may do, in the scope vocabulary that access
572/// tokens use (see [`crate::scopes`]): the scopes of its operations, and
573/// for a runner, git's. Its operations, its repository and its run still
574/// bound it more tightly than these scopes say.
575pub fn run_scopes(kind: RunCredentialKind, usage: CredentialUse) -> Vec<crate::scopes::Scope> {
576 use crate::scopes::{Scope, normalize, scope_for};
577 let mut scopes: Vec<Scope> = operations_for(kind, usage)
578 .into_iter()
579 .filter_map(scope_for)
580 .collect();
581 if usage == CredentialUse::Runner {
582 scopes.push(Scope::CodeRead);
583 if matches!(
584 kind,
585 RunCredentialKind::Implement
586 | RunCredentialKind::Revise
587 | RunCredentialKind::Answer
588 | RunCredentialKind::Update
589 | RunCredentialKind::Bump
590 ) {
591 scopes.push(Scope::CodeWrite);
592 }
593 }
594 normalize(&mut scopes);
595 scopes
596}
597
598/// Operations that change a pull request, which a runner may do only to
599/// the pull request its run works on.
600const PULL_WRITES: &[&str] = &["record_session", "mark_pull_request_ready"];
601
602/// Whether something was allowed, and the rule that decided it.
603#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
604pub struct Decision {
605 pub allowed: bool,
606 /// A short, stable name: `run:implement/tools`, `never`,
607 /// `scope:repository` and so on. Shown in the audit log.
608 pub rule: String,
609 /// Why it was refused, for the caller.
610 #[serde(default, skip_serializing_if = "Option::is_none")]
611 pub reason: Option<String>,
612}
613
614impl Decision {
615 pub fn allow(rule: impl Into<String>) -> Self {
616 Decision {
617 allowed: true,
618 rule: rule.into(),
619 reason: None,
620 }
621 }
622
623 pub fn deny(rule: impl Into<String>, reason: impl Into<String>) -> Self {
624 Decision {
625 allowed: false,
626 rule: rule.into(),
627 reason: Some(reason.into()),
628 }
629 }
630}
631
632fn same_repo(a: &RepoPath, b: &RepoPath) -> bool {
633 a.namespace.eq_ignore_ascii_case(&b.namespace) && a.name.eq_ignore_ascii_case(&b.name)
634}
635
636fn scope_rule(scope: &AgentScope) -> String {
637 match &scope.run {
638 Some(run) => format!("run:{}/{}", run.kind.as_str(), run.usage.as_str()),
639 None => "agent-token".to_owned(),
640 }
641}
642
643/// Whether `user`, resolved from an agent's token with `scope`, may use
644/// `operation`. `repo` is the repository the call names, if any, and
645/// `needs_repo` whether the operation is about one; `number` the issue or
646/// pull request it names.
647pub fn decide_operation(
648 user: &User,
649 scope: &AgentScope,
650 operation: &str,
651 repo: Option<&RepoPath>,
652 needs_repo: bool,
653 number: Option<u32>,
654) -> Decision {
655 let who = "A g1t agent's token";
656 if NEVER.contains(&operation) {
657 return Decision::deny(
658 "never",
659 format!(
660 "{who} can never use {operation}: settings, members, tokens, billing, integrations, webhooks, secrets and merging are for people."
661 ),
662 );
663 }
664 if !scope.operations.iter().any(|name| name == operation) {
665 return Decision::deny(
666 "scope:operation",
667 format!("{who} for this run cannot use {operation}."),
668 );
669 }
670 if needs_repo && !repo.is_some_and(|asked| same_repo(asked, &scope.repo)) {
671 return Decision::deny(
672 "scope:repository",
673 format!(
674 "{who} works in {}/{} only.",
675 scope.repo.namespace, scope.repo.name
676 ),
677 );
678 }
679 // The intersection: the person it acts for must still be able to work
680 // in the repository's workspace, as a member or with a role on its
681 // repositories. What it may do in the repository itself is their
682 // role there, which services check (`access::can`).
683 if !crate::access::has_access_in(user, &scope.repo.namespace) {
684 return Decision::deny(
685 "on-behalf-of:membership",
686 format!(
687 "The person this agent works for is no longer a member of {}.",
688 scope.repo.namespace
689 ),
690 );
691 }
692 if let Some(run) = &scope.run
693 && run.usage == CredentialUse::Runner
694 && PULL_WRITES.contains(&operation)
695 && run.number.is_some()
696 && number != run.number
697 {
698 return Decision::deny(
699 "scope:pull",
700 format!(
701 "{who} can change pull request #{} only.",
702 run.number.unwrap_or_default()
703 ),
704 );
705 }
706 Decision::allow(scope_rule(scope))
707}
708
709/// Whether a run credential may clone or fetch (`write` false), or push to
710/// (`write` true), the repository at `repo`.
711pub fn decide_git(scope: &AgentScope, repo: &RepoPath, write: bool) -> Decision {
712 let Some(run) = scope
713 .run
714 .as_ref()
715 .filter(|run| run.usage == CredentialUse::Runner)
716 else {
717 return Decision::deny(
718 "git:not-a-run",
719 "A g1t agent's tools token cannot be used with git.",
720 );
721 };
722 let pushable = run.push.iter().any(|grant| same_repo(&grant.repo, repo));
723 if write {
724 return if pushable {
725 Decision::allow(format!("{}:push", scope_rule(scope)))
726 } else {
727 Decision::deny(
728 "git:push",
729 format!(
730 "A {} run cannot push to {}/{}.",
731 run.kind.as_str(),
732 repo.namespace,
733 repo.name
734 ),
735 )
736 };
737 }
738 let readable = pushable
739 || same_repo(&scope.repo, repo)
740 || run.read.iter().any(|path| same_repo(path, repo));
741 if readable {
742 Decision::allow(format!("{}:read", scope_rule(scope)))
743 } else {
744 Decision::deny(
745 "git:read",
746 format!(
747 "A {} run cannot read {}/{}.",
748 run.kind.as_str(),
749 repo.namespace,
750 repo.name
751 ),
752 )
753 }
754}
755
756/// Whether a push to `repo` is limited to certain branches, so that the
757/// refs it moves have to be read and checked with [`decide_refs`].
758pub fn limits_branches(scope: &AgentScope, repo: &RepoPath) -> bool {
759 scope
760 .run
761 .iter()
762 .flat_map(|run| run.push.iter())
763 .any(|grant| same_repo(&grant.repo, repo) && grant.branch.is_some())
764}
765
766/// Whether a push to `repo` may move `refs` (full refs, such as
767/// `refs/heads/main`). Tags are never a run's to move.
768pub fn decide_refs(scope: &AgentScope, repo: &RepoPath, refs: &[String]) -> Decision {
769 let repo_decision = decide_git(scope, repo, true);
770 if !repo_decision.allowed {
771 return repo_decision;
772 }
773 let grants: Vec<&GitGrant> = scope
774 .run
775 .iter()
776 .flat_map(|run| run.push.iter())
777 .filter(|grant| same_repo(&grant.repo, repo))
778 .collect();
779 for git_ref in refs {
780 let Some(branch) = git_ref.strip_prefix("refs/heads/") else {
781 return Decision::deny("git:ref", format!("A run cannot push {git_ref}."));
782 };
783 let allowed = grants
784 .iter()
785 .any(|grant| grant.branch.as_deref().is_none_or(|only| only == branch));
786 if !allowed {
787 return Decision::deny(
788 "git:ref",
789 format!(
790 "A run cannot push to {branch} in {}/{}.",
791 repo.namespace, repo.name
792 ),
793 );
794 }
795 }
796 repo_decision
797}
798
799/// The most an agent may be on a repository, whoever it works for: it
800/// can push, merge and run, never change settings or who has access.
801pub const AGENT_CEILING: RepoRole = RepoRole::Write;
802
803/// The memberships an agent working for `person` has: the run's
804/// workspace, as a member, only if the person is in it now, with the
805/// person's role on its repositories (an owner's Admin included) cut down
806/// to [`AGENT_CEILING`].
807pub fn intersect(person: &[Membership], namespace: &str) -> Vec<Membership> {
808 let namespace = namespace.to_lowercase();
809 person
810 .iter()
811 .filter(|membership| membership.slug == namespace)
812 .map(|membership| {
813 let base = match membership.role {
814 Role::Owner => BasePermission::Admin,
815 Role::Member => membership.base_permission.unwrap_or_default(),
816 };
817 Membership {
818 role: Role::Member,
819 base_permission: Some(match base {
820 BasePermission::Admin => BasePermission::Write,
821 base => base,
822 }),
823 // Billing and security manager are the person's, never
824 // their agent's.
825 org_roles: Vec::new(),
826 ..membership.clone()
827 }
828 })
829 .collect()
830}
831
832/// The repository grants an agent working for `person` has: those in the
833/// run's workspace, each cut down to [`AGENT_CEILING`].
834pub fn intersect_grants(person: &[RepoGrant], namespace: &str) -> Vec<RepoGrant> {
835 let namespace = namespace.to_lowercase();
836 person
837 .iter()
838 .filter(|grant| grant.workspace == namespace)
839 .map(|grant| RepoGrant {
840 role: grant.role.min(AGENT_CEILING),
841 ..grant.clone()
842 })
843 .collect()
844}
845
846/// Who a runner's credential acts as downstream: the person, with only the
847/// agent's (already intersected) memberships. `None` for anything else.
848pub fn as_person(user: &User) -> Option<User> {
849 let acting = user.acting.as_ref()?;
850 if user.kind != PrincipalKind::Agent {
851 return None;
852 }
853 let run = acting.run()?;
854 if run.usage != CredentialUse::Runner {
855 return None;
856 }
857 Some(User {
858 id: acting.on_behalf_of.id.clone(),
859 username: acting.on_behalf_of.username.clone(),
860 display_username: None,
861 kind: PrincipalKind::User,
862 verified: user.verified,
863 workspaces: user.workspaces.clone(),
864 avatar: None,
865 acting: None,
866 grants: user.grants.clone(),
867 token: None,
868 held: Vec::new(),
869 })
870}
871
872/// How an actor is described: "g1t on behalf of syntaqx".
873pub fn describe(user: &User) -> String {
874 match &user.acting {
875 Some(acting) => format!(
876 "{} on behalf of {}",
877 acting.agent, acting.on_behalf_of.username
878 ),
879 None => user.username.clone(),
880 }
881}
882
883#[cfg(test)]
884mod tests {
885 use super::*;
886
887 #[test]
888 fn a_run_s_scopes_are_never_admin() {
889 for kind in RunCredentialKind::ALL {
890 for usage in [CredentialUse::Runner, CredentialUse::Tools] {
891 let scopes = run_scopes(kind, usage);
892 assert!(scopes.iter().all(|scope| !scope.dangerous()), "{kind:?} {usage:?}: {scopes:?}");
893 }
894 }
895 let review = run_scopes(RunCredentialKind::Review, CredentialUse::Tools);
896 assert!(review.contains(&crate::scopes::Scope::PullRequestsWrite));
897 assert!(!review.contains(&crate::scopes::Scope::CodeWrite));
898 }
899
900 #[test]
901 fn agents_can_search_the_context_hub() {
902 for kind in [RunCredentialKind::Implement, RunCredentialKind::Review, RunCredentialKind::Plan] {
903 let tools = operations_for(kind, CredentialUse::Tools);
904 assert!(tools.contains(&"search_context") && tools.contains(&"get_entity"));
905 }
906 assert!(is_read("search_context") && is_read("get_entity"));
907 }
908
909 #[test]
910 fn agents_can_search_all_of_g1t() {
911 // Site-wide search only reads: every run that reads its repository
912 // may use it, and nothing that never reads gets it.
913 assert!(is_read("search"));
914 assert!(!NEVER.contains(&"search"));
915 for kind in [
916 RunCredentialKind::Implement,
917 RunCredentialKind::Revise,
918 RunCredentialKind::Answer,
919 RunCredentialKind::Review,
920 RunCredentialKind::Plan,
921 RunCredentialKind::Update,
922 ] {
923 let tools = operations_for(kind, CredentialUse::Tools);
924 assert!(tools.contains(&"search"), "{kind:?} should search");
925 // The context hub's search stays its own tool beside it.
926 assert!(tools.contains(&"search_context"), "{kind:?} keeps search_context");
927 }
928 for kind in [RunCredentialKind::Checks, RunCredentialKind::Queue, RunCredentialKind::Mergecheck, RunCredentialKind::Deploy, RunCredentialKind::Bump] {
929 assert!(!operations_for(kind, CredentialUse::Tools).contains(&"search"));
930 }
931 assert!(!operations_for(RunCredentialKind::Implement, CredentialUse::Runner).contains(&"search"));
932 }
933
934 fn path(namespace: &str, name: &str) -> RepoPath {
935 RepoPath {
936 namespace: namespace.to_owned(),
937 name: name.to_owned(),
938 }
939 }
940
941 fn scope(kind: RunCredentialKind, usage: CredentialUse) -> AgentScope {
942 AgentScope {
943 repo: path("acme", "rocket"),
944 operations: operations_for(kind, usage)
945 .into_iter()
946 .map(str::to_owned)
947 .collect(),
948 run: Some(RunBinding {
949 kind,
950 usage,
951 run_id: Some("run_1".to_owned()),
952 number: Some(7),
953 agent: "g1t".to_owned(),
954 system: false,
955 read: vec![path("acme", "rocket")],
956 push: match kind {
957 RunCredentialKind::Implement
958 | RunCredentialKind::Revise
959 | RunCredentialKind::Answer => vec![GitGrant {
960 repo: path("pulls", "pul_7"),
961 branch: None,
962 }],
963 RunCredentialKind::Update => vec![GitGrant {
964 repo: path("acme", "rocket"),
965 branch: Some("fix-login".to_owned()),
966 }],
967 _ => vec![],
968 },
969 }),
970 }
971 }
972
973 fn agent(member_of: &[&str], scope: AgentScope) -> User {
974 User {
975 id: "usr_g1t_agent".to_owned(),
976 username: "g1t".to_owned(),
977 display_username: None,
978 kind: PrincipalKind::Agent,
979 verified: true,
980 workspaces: member_of
981 .iter()
982 .map(|slug| Membership::member(*slug))
983 .collect(),
984 avatar: None,
985 grants: Vec::new(),
986 token: None,
987 held: Vec::new(),
988 acting: Some(Box::new(Acting {
989 credential_id: "tok_1".to_owned(),
990 agent: "g1t".to_owned(),
991 on_behalf_of: Principal {
992 id: "usr_1".to_owned(),
993 username: "syntaqx".to_owned(),
994 },
995 scope,
996 })),
997 }
998 }
999
1000 fn op(kind: RunCredentialKind, usage: CredentialUse, operation: &str) -> Decision {
1001 let scope = scope(kind, usage);
1002 let user = agent(&["acme"], scope.clone());
1003 decide_operation(
1004 &user,
1005 &scope,
1006 operation,
1007 Some(&path("acme", "rocket")),
1008 true,
1009 Some(7),
1010 )
1011 }
1012
1013 use CredentialUse::{Runner, Tools};
1014 use RunCredentialKind as K;
1015
1016 /// Which operations each kind of run may use through its tools: the
1017 /// allowed and denied matrix.
1018 #[test]
1019 fn tools_matrix() {
1020 let cases: [(&str, [bool; 6]); 12] = [
1021 // implement revise answer review plan checks
1022 ("get_issue", [true, true, true, true, true, false]),
1023 ("create_issue", [true, true, true, false, true, false]),
1024 ("add_comment", [true, true, true, true, false, false]),
1025 (
1026 "review_pull_request",
1027 [false, false, false, true, false, false],
1028 ),
1029 ("remember", [true, true, true, false, false, false]),
1030 ("take_messages", [true, true, true, false, false, false]),
1031 ("record_session", [false, false, false, false, false, false]),
1032 (
1033 "merge_pull_request",
1034 [false, false, false, false, false, false],
1035 ),
1036 (
1037 "update_repo_settings",
1038 [false, false, false, false, false, false],
1039 ),
1040 ("create_webhook", [false, false, false, false, false, false]),
1041 (
1042 "set_actions_secret",
1043 [false, false, false, false, false, false],
1044 ),
1045 ("assign_issue", [false, false, false, false, false, false]),
1046 ];
1047 let kinds = [
1048 K::Implement,
1049 K::Revise,
1050 K::Answer,
1051 K::Review,
1052 K::Plan,
1053 K::Checks,
1054 ];
1055 for (operation, expected) in cases {
1056 for (kind, allowed) in kinds.into_iter().zip(expected) {
1057 assert_eq!(
1058 op(kind, Tools, operation).allowed,
1059 allowed,
1060 "{operation} by a {} run's tools",
1061 kind.as_str()
1062 );
1063 }
1064 }
1065 }
1066
1067 #[test]
1068 fn runner_matrix() {
1069 assert!(op(K::Implement, Runner, "record_session").allowed);
1070 assert!(op(K::Implement, Runner, "mark_pull_request_ready").allowed);
1071 assert!(op(K::Revise, Runner, "record_session").allowed);
1072 assert!(!op(K::Revise, Runner, "mark_pull_request_ready").allowed);
1073 assert!(!op(K::Implement, Runner, "create_issue").allowed);
1074 assert!(!op(K::Review, Runner, "record_session").allowed);
1075 assert!(!op(K::Checks, Runner, "get_issue").allowed);
1076 }
1077
1078 #[test]
1079 fn settings_billing_tokens_and_members_are_never_reachable() {
1080 for kind in RunCredentialKind::ALL {
1081 for usage in [Runner, Tools] {
1082 for operation in NEVER.iter().copied() {
1083 let decision = op(kind, usage, operation);
1084 assert!(!decision.allowed);
1085 assert_eq!(decision.rule, "never");
1086 }
1087 }
1088 }
1089 // Even a scope that lists one is refused.
1090 let mut wide = scope(K::Implement, Tools);
1091 wide.operations.push("merge_pull_request".to_owned());
1092 let user = agent(&["acme"], wide.clone());
1093 let decision = decide_operation(
1094 &user,
1095 &wide,
1096 "merge_pull_request",
1097 Some(&path("acme", "rocket")),
1098 true,
1099 Some(7),
1100 );
1101 assert_eq!(decision.rule, "never");
1102 }
1103
1104 #[test]
1105 fn another_repository_is_refused() {
1106 let scope = scope(K::Implement, Tools);
1107 let user = agent(&["acme"], scope.clone());
1108 let decision = decide_operation(
1109 &user,
1110 &scope,
1111 "create_issue",
1112 Some(&path("acme", "other")),
1113 true,
1114 None,
1115 );
1116 assert!(!decision.allowed);
1117 assert_eq!(decision.rule, "scope:repository");
1118 let decision = decide_operation(&user, &scope, "create_issue", None, true, None);
1119 assert_eq!(decision.rule, "scope:repository");
1120 // The repository's name is matched without regard to case.
1121 let decision = decide_operation(
1122 &user,
1123 &scope,
1124 "create_issue",
1125 Some(&path("Acme", "Rocket")),
1126 true,
1127 None,
1128 );
1129 assert!(decision.allowed);
1130 assert_eq!(decision.rule, "run:implement/tools");
1131 }
1132
1133 #[test]
1134 fn the_permission_is_the_intersection_with_the_person() {
1135 let scope = scope(K::Implement, Tools);
1136 // The person left the workspace: their agent can do nothing there.
1137 let user = agent(&[], scope.clone());
1138 let decision = decide_operation(
1139 &user,
1140 &scope,
1141 "get_issue",
1142 Some(&path("acme", "rocket")),
1143 true,
1144 Some(1),
1145 );
1146 assert!(!decision.allowed);
1147 assert_eq!(decision.rule, "on-behalf-of:membership");
1148 // And an owner's agent is only ever a member.
1149 let owner = vec![
1150 Membership {
1151 slug: "acme".to_owned(),
1152 role: Role::Owner,
1153 name: None,
1154 avatar: None,
1155 base_permission: Some(BasePermission::None),
1156 team_creation: None,
1157 org_roles: vec![crate::OrgRole::SecurityManager],
1158 privileges: None,
1159 },
1160 Membership::member("elsewhere"),
1161 ];
1162 let memberships = intersect(&owner, "Acme");
1163 assert_eq!(memberships.len(), 1);
1164 assert_eq!(memberships[0].slug, "acme");
1165 assert_eq!(memberships[0].role, Role::Member);
1166 assert!(memberships[0].org_roles.is_empty());
1167 assert!(intersect(&owner, "nowhere").is_empty());
1168 }
1169
1170 /// An agent gets at most the person's role on the repository, and
1171 /// never more than Write; nothing outside the run's workspace.
1172 #[test]
1173 fn an_agent_has_at_most_its_persons_role() {
1174 use crate::access::{Capability, RepoRef, can, permission};
1175 let rocket = RepoRef { id: "rep_1", namespace: "acme", private: true };
1176 let other = RepoRef { id: "rep_2", namespace: "acme", private: true };
1177 let elsewhere = RepoRef { id: "rep_3", namespace: "globex", private: true };
1178 let tools = scope(K::Implement, Tools);
1179 let scope = scope(K::Implement, Runner);
1180 // An owner's agent: Write, never Admin.
1181 let owner = [Membership { role: Role::Owner, ..Membership::member("acme") }, Membership::member("globex")];
1182 let mut agent_user = agent(&[], scope.clone());
1183 agent_user.workspaces = intersect(&owner, "acme");
1184 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Write));
1185 assert!(!can(Some(&agent_user), rocket, Capability::ManageSettings));
1186 assert_eq!(permission(Some(&agent_user), elsewhere), None);
1187 // A member whose workspace gives Read: Read, so it cannot push.
1188 let reader = [Membership { base_permission: Some(BasePermission::Read), ..Membership::member("acme") }];
1189 agent_user.workspaces = intersect(&reader, "acme");
1190 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Read));
1191 assert!(!can(Some(&agent_user), rocket, Capability::Push));
1192 // An outside collaborator with Maintain on one repository: Write
1193 // there, nothing elsewhere, and the run is allowed.
1194 let grants = [
1195 RepoGrant { repo_id: "rep_1".into(), workspace: "acme".into(), role: RepoRole::Maintain, team: None },
1196 RepoGrant { repo_id: "rep_3".into(), workspace: "globex".into(), role: RepoRole::Admin, team: None },
1197 ];
1198 agent_user.workspaces = intersect(&[], "acme");
1199 agent_user.grants = intersect_grants(&grants, "Acme");
1200 assert_eq!(permission(Some(&agent_user), rocket), Some(RepoRole::Write));
1201 assert_eq!(permission(Some(&agent_user), other), None);
1202 assert_eq!(permission(Some(&agent_user), elsewhere), None);
1203 let decision = decide_operation(&agent_user, &tools, "get_issue", Some(&path("acme", "rocket")), true, Some(1));
1204 assert!(decision.allowed, "{}", decision.reason.unwrap_or_default());
1205 // The person, downstream of a runner's credential, carries the same.
1206 let person = as_person(&agent_user).expect("a runner acts as the person");
1207 assert_eq!(permission(Some(&person), rocket), Some(RepoRole::Write));
1208 }
1209
1210 #[test]
1211 fn a_runner_changes_only_its_own_pull_request() {
1212 let scope = scope(K::Implement, Runner);
1213 let user = agent(&["acme"], scope.clone());
1214 let repo = path("acme", "rocket");
1215 let other = decide_operation(&user, &scope, "record_session", Some(&repo), true, Some(8));
1216 assert!(!other.allowed);
1217 assert_eq!(other.rule, "scope:pull");
1218 let own = decide_operation(&user, &scope, "record_session", Some(&repo), true, Some(7));
1219 assert!(own.allowed);
1220 // Reading another is fine.
1221 assert!(
1222 decide_operation(
1223 &user,
1224 &scope,
1225 "get_pull_request",
1226 Some(&repo),
1227 true,
1228 Some(8)
1229 )
1230 .allowed
1231 );
1232 }
1233
1234 #[test]
1235 fn git_matrix() {
1236 let fork = path("pulls", "pul_7");
1237 let upstream = path("acme", "rocket");
1238 let elsewhere = path("acme", "billing");
1239 let implement = scope(K::Implement, Runner);
1240 assert!(decide_git(&implement, &fork, true).allowed);
1241 assert!(decide_git(&implement, &fork, false).allowed);
1242 assert!(decide_git(&implement, &upstream, false).allowed);
1243 assert_eq!(decide_git(&implement, &upstream, true).rule, "git:push");
1244 assert_eq!(decide_git(&implement, &elsewhere, false).rule, "git:read");
1245 let review = scope(K::Review, Runner);
1246 assert!(decide_git(&review, &upstream, false).allowed);
1247 assert!(!decide_git(&review, &upstream, true).allowed);
1248 assert!(!decide_git(&review, &fork, true).allowed);
1249 // A tools token made before run credentials never reaches git.
1250 let old = AgentScope {
1251 repo: upstream.clone(),
1252 operations: vec!["get_issue".to_owned()],
1253 run: None,
1254 };
1255 assert_eq!(decide_git(&old, &upstream, false).rule, "git:not-a-run");
1256 // Nor does an agent's tools token.
1257 assert_eq!(
1258 decide_git(&scope(K::Implement, Tools), &upstream, false).rule,
1259 "git:not-a-run"
1260 );
1261 }
1262
1263 #[test]
1264 fn a_push_moves_only_granted_branches() {
1265 let update = scope(K::Update, Runner);
1266 let repo = path("acme", "rocket");
1267 let refs = |names: &[&str]| {
1268 names
1269 .iter()
1270 .map(|name| (*name).to_owned())
1271 .collect::<Vec<_>>()
1272 };
1273 assert!(decide_refs(&update, &repo, &refs(&["refs/heads/fix-login"])).allowed);
1274 assert_eq!(
1275 decide_refs(&update, &repo, &refs(&["refs/heads/main"])).rule,
1276 "git:ref"
1277 );
1278 assert_eq!(
1279 decide_refs(
1280 &update,
1281 &repo,
1282 &refs(&["refs/heads/fix-login", "refs/tags/v1"])
1283 )
1284 .rule,
1285 "git:ref"
1286 );
1287 let implement = scope(K::Implement, Runner);
1288 assert!(
1289 decide_refs(
1290 &implement,
1291 &path("pulls", "pul_7"),
1292 &refs(&["refs/heads/main"])
1293 )
1294 .allowed
1295 );
1296 }
1297
1298 #[test]
1299 fn a_runner_acts_downstream_as_the_person() {
1300 let user = agent(&["acme"], scope(K::Implement, Runner));
1301 let person = as_person(&user).unwrap();
1302 assert_eq!(person.id, "usr_1");
1303 assert_eq!(person.username, "syntaqx");
1304 assert_eq!(person.kind, PrincipalKind::User);
1305 assert!(person.is_member("acme"));
1306 assert!(person.acting.is_none());
1307 assert_eq!(describe(&user), "g1t on behalf of syntaqx");
1308 // The tools act as the agent.
1309 assert!(as_person(&agent(&["acme"], scope(K::Implement, Tools))).is_none());
1310 }
1311
1312 #[test]
1313 fn scopes_without_a_run_still_parse() {
1314 let old: AgentScope = serde_json::from_str(
1315 r#"{"repo":{"namespace":"acme","name":"rocket"},"operations":["get_issue"]}"#,
1316 )
1317 .unwrap();
1318 assert!(old.run.is_none());
1319 let written = serde_json::to_string(&scope(K::Review, Tools)).unwrap();
1320 assert!(written.contains(r#""use":"tools""#));
1321 assert!(written.contains(r#""kind":"review""#));
1322 let back: AgentScope = serde_json::from_str(&written).unwrap();
1323 assert_eq!(back.run.unwrap().kind, K::Review);
1324 // Only g1t's own runs say so; every other reads as not.
1325 assert!(!written.contains("system"));
1326 assert!(!back_run(&written).system);
1327 let mut own = scope(K::Bump, Runner);
1328 own.run.as_mut().unwrap().system = true;
1329 let written = serde_json::to_string(&own).unwrap();
1330 assert!(written.contains(r#""system":true"#));
1331 assert!(back_run(&written).system);
1332 }
1333
1334 fn back_run(written: &str) -> RunBinding {
1335 serde_json::from_str::<AgentScope>(written).unwrap().run.unwrap()
1336 }
1337}