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