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Where people and agents ship software together. The open-source git platform for the whole job: issues, agents, checks and deploys to the edge.

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g1t/services/identity/src/tokens.rs

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1//! Access tokens: the `g1t_…` secrets used by git, the API and the MCP
2//! server.
3//!
4//! There is one implementation and two kinds of owner. A personal token
5//! acts as the person who made it. A workspace's token belongs to the
6//! workspace and acts as it, so automation needs no account of its own and
7//! keeps working when the member who set it up leaves.
8
9use g1t_contracts::identity::*;
10use g1t_contracts::time::{SQL_NOW, rfc3339};
11use g1t_contracts::{FailureCode, Membership, Outcome, PrincipalKind, Role, User, Viewer, new_id};
12use g1t_kit::now_ms;
13use serde::Deserialize;
14use worker::Result;
15use worker::wasm_bindgen::JsValue;
16
17use crate::{Identity, crypto};
18
19pub const TOKEN_PREFIX: &str = "g1t_";
20/// How stale a token's last-used time may get before it is written again.
21const LAST_USED_RESOLUTION_MS: u64 = 5 * 60 * 1000;
22const MAX_TOKENS_PER_WORKSPACE: usize = 50;
23const WORKSPACE_ID_PREFIX: &str = "wsp_";
24
25const TOKEN_COLUMNS: &str = "access_tokens.id, access_tokens.name, access_tokens.created_at,
26 access_tokens.last_used_at, users.username AS created_by";
27
28/// Who a new token belongs to.
29enum Owner<'a> {
30 User(&'a str),
31 Workspace {
32 id: &'a str,
33 created_by: Option<&'a str>,
34 },
35}
36
37#[derive(Deserialize)]
38struct TokenRow {
39 id: String,
40 name: String,
41 created_at: String,
42 last_used_at: Option<String>,
43 created_by: Option<String>,
44}
45
46impl From<TokenRow> for AccessToken {
47 fn from(row: TokenRow) -> Self {
48 AccessToken {
49 id: row.id,
50 name: row.name,
51 created_at: row.created_at,
52 last_used_at: row.last_used_at,
53 created_by: row.created_by,
54 }
55 }
56}
57
58/// The owner of a token being used.
59#[derive(Deserialize)]
60struct Presented {
61 id: String,
62 user_id: Option<String>,
63 workspace_id: Option<String>,
64 last_used_at: Option<String>,
65 /// Set on an agent's token: what it may do, as JSON `AgentScope`.
66 agent_scope: Option<String>,
67}
68
69#[derive(Deserialize)]
70struct WorkspaceRef {
71 id: String,
72 slug: String,
73}
74
75fn text(value: Option<&str>) -> JsValue {
76 value.map_or(JsValue::NULL, JsValue::from)
77}
78
79impl Identity {
80 pub async fn user_for_access_token(&self, token: &str) -> Result<Viewer> {
81 if !token.starts_with(TOKEN_PREFIX) {
82 return Ok(None);
83 }
84 let Some(presented) = self
85 .db
86 .prepare(format!(
87 "SELECT id, user_id, workspace_id, last_used_at, agent_scope FROM access_tokens
88 WHERE token_hash = ? AND (expires_at IS NULL OR expires_at > {SQL_NOW})"
89 ))
90 .bind(&[crypto::sha256_hex(token).into()])?
91 .first::<Presented>(None)
92 .await?
93 else {
94 return Ok(None);
95 };
96 // An agent's token: g1t-agent, a member of its repository's
97 // workspace, and only for what its scope lists.
98 if let Some(scope) = presented
99 .agent_scope
100 .as_deref()
101 .and_then(|scope| serde_json::from_str::<AgentScope>(scope).ok())
102 {
103 return Ok(Some(User {
104 id: AGENT_ID.to_owned(),
105 username: AGENT_NAME.to_owned(),
106 kind: PrincipalKind::Agent,
107 verified: true,
108 workspaces: vec![Membership {
109 slug: scope.repo.namespace,
110 role: Role::Member,
111 }],
112 }));
113 }
114 let viewer = match (&presented.user_id, &presented.workspace_id) {
115 (Some(user_id), _) => {
116 self.find_user(
117 "SELECT id, username, email_verified_at IS NOT NULL AS verified
118 FROM users WHERE id = ?",
119 user_id,
120 )
121 .await?
122 }
123 (None, Some(workspace_id)) => self.workspace_principal(workspace_id).await?,
124 (None, None) => None,
125 };
126 if viewer.is_some() {
127 self.note_use(&presented).await?;
128 }
129 Ok(viewer)
130 }
131
132 /// A workspace as the actor behind one of its own tokens. It can do
133 /// what a member can, in that workspace only.
134 async fn workspace_principal(&self, workspace_id: &str) -> Result<Viewer> {
135 let workspace = self
136 .db
137 .prepare("SELECT id, slug FROM workspaces WHERE id = ?")
138 .bind(&[workspace_id.into()])?
139 .first::<WorkspaceRef>(None)
140 .await?;
141 Ok(workspace.map(|workspace| User {
142 id: workspace.id,
143 username: workspace.slug.clone(),
144 kind: PrincipalKind::Workspace,
145 verified: true,
146 workspaces: vec![Membership {
147 slug: workspace.slug,
148 role: Role::Member,
149 }],
150 }))
151 }
152
153 async fn note_use(&self, presented: &Presented) -> Result<()> {
154 let now = now_ms();
155 let stale = rfc3339(now.saturating_sub(LAST_USED_RESOLUTION_MS));
156 if presented
157 .last_used_at
158 .as_deref()
159 .is_some_and(|at| at >= stale.as_str())
160 {
161 return Ok(());
162 }
163 self.db
164 .prepare("UPDATE access_tokens SET last_used_at = ? WHERE id = ?")
165 .bind(&[rfc3339(now).into(), presented.id.as_str().into()])?
166 .run()
167 .await?;
168 Ok(())
169 }
170
171 async fn mint(
172 &self,
173 owner: Owner<'_>,
174 name: &str,
175 ttl_seconds: Option<u64>,
176 ) -> Result<CreatedAccessToken> {
177 let token = format!("{TOKEN_PREFIX}{}", crypto::random_hex(20));
178 let now = now_ms();
179 let name: String = match name.trim() {
180 "" => "Access token".to_owned(),
181 name => name.chars().take(100).collect(),
182 };
183 let (user_id, workspace_id, created_by) = match owner {
184 Owner::User(id) => (Some(id), None, Some(id)),
185 Owner::Workspace { id, created_by } => (None, Some(id), created_by),
186 };
187 let info = AccessToken {
188 id: new_id("tok", now),
189 name,
190 created_at: rfc3339(now),
191 last_used_at: None,
192 created_by: None,
193 };
194 self.db
195 .prepare(
196 "INSERT INTO access_tokens
197 (id, user_id, workspace_id, created_by, name, token_hash, created_at, expires_at)
198 VALUES (?, ?, ?, ?, ?, ?, ?, ?)",
199 )
200 .bind(&[
201 info.id.as_str().into(),
202 text(user_id),
203 text(workspace_id),
204 text(created_by),
205 info.name.as_str().into(),
206 crypto::sha256_hex(&token).into(),
207 info.created_at.as_str().into(),
208 ttl_seconds.map_or(JsValue::NULL, |ttl| rfc3339(now + ttl * 1000).into()),
209 ])?
210 .run()
211 .await?;
212 Ok(CreatedAccessToken { token, info })
213 }
214
215 pub async fn create_access_token(
216 &self,
217 a: CreateAccessTokenArgs,
218 ) -> Result<CreatedAccessToken> {
219 // Told apart by the id, which says what it names, since callers pass
220 // on actors that other services stored as an id and a name.
221 let owner = if a.user.id.starts_with(WORKSPACE_ID_PREFIX) {
222 Owner::Workspace {
223 id: &a.user.id,
224 created_by: None,
225 }
226 } else {
227 Owner::User(&a.user.id)
228 };
229 self.mint(owner, &a.name, a.ttl_seconds).await
230 }
231
232 /// A token for a g1t agent working for `on_behalf_of`, which can do
233 /// only what `scope` lists. It is recorded as theirs, so it is listed and
234 /// can be deleted with their other tokens.
235 pub async fn create_agent_token(&self, a: CreateAgentTokenArgs) -> Result<CreatedAccessToken> {
236 let created = self
237 .mint(
238 Owner::User(&a.on_behalf_of.id),
239 &format!("g1t agent in {}/{}", a.scope.repo.namespace, a.scope.repo.name),
240 Some(a.ttl_seconds),
241 )
242 .await?;
243 self.db
244 .prepare("UPDATE access_tokens SET agent_scope = ? WHERE id = ?")
245 .bind(&[
246 serde_json::to_string(&a.scope)?.into(),
247 created.info.id.as_str().into(),
248 ])?
249 .run()
250 .await?;
251 Ok(created)
252 }
253
254 /// What an agent's token may do, or `None` for any other token.
255 pub async fn agent_scope(&self, a: TokenArgs) -> Result<Option<AgentScope>> {
256 let scope: Option<Option<String>> = self
257 .db
258 .prepare(format!(
259 "SELECT agent_scope FROM access_tokens
260 WHERE token_hash = ? AND (expires_at IS NULL OR expires_at > {SQL_NOW})"
261 ))
262 .bind(&[crypto::sha256_hex(&a.token).into()])?
263 .first::<Option<String>>(Some("agent_scope"))
264 .await?;
265 Ok(scope
266 .flatten()
267 .and_then(|scope| serde_json::from_str(&scope).ok()))
268 }
269
270 pub async fn list_access_tokens(&self, a: UserArgs) -> Result<Vec<AccessToken>> {
271 self.tokens_where("access_tokens.user_id = ?", &a.user.id)
272 .await
273 }
274
275 /// Tokens that do not expire: the ones a person made on purpose, rather
276 /// than those issued to an application or a hosted agent.
277 async fn tokens_where(&self, owner: &str, id: &str) -> Result<Vec<AccessToken>> {
278 let rows = self
279 .db
280 .prepare(format!(
281 "SELECT {TOKEN_COLUMNS} FROM access_tokens
282 LEFT JOIN users ON users.id = access_tokens.created_by
283 WHERE {owner} AND access_tokens.expires_at IS NULL
284 ORDER BY access_tokens.id"
285 ))
286 .bind(&[id.into()])?
287 .all()
288 .await?
289 .results::<TokenRow>()?;
290 Ok(rows.into_iter().map(AccessToken::from).collect())
291 }
292
293 pub async fn list_workspace_tokens(
294 &self,
295 a: WorkspaceTokensArgs,
296 ) -> Result<Outcome<Vec<AccessToken>>> {
297 let slug = a.slug.to_lowercase();
298 if !a.viewer.is_some_and(|viewer| viewer.is_member(&slug)) {
299 return Ok(Outcome::fail(
300 FailureCode::Forbidden,
301 "Only members can see a workspace's access tokens.",
302 ));
303 }
304 let Some(workspace) = self.get_workspace(SlugArgs { slug }).await? else {
305 return Ok(Outcome::fail(FailureCode::NotFound, "Workspace not found."));
306 };
307 Ok(Outcome::Ok(
308 self.tokens_where("access_tokens.workspace_id = ?", &workspace.id)
309 .await?,
310 ))
311 }
312
313 /// The workspace's id, if `actor` is a person who owns it.
314 async fn owned_workspace(&self, actor: &User, slug: &str) -> Result<Outcome<String>> {
315 let slug = slug.to_lowercase();
316 if actor.kind != PrincipalKind::User || actor.role_in(&slug) != Some(Role::Owner) {
317 return Ok(Outcome::fail(
318 FailureCode::Forbidden,
319 "Only an owner can manage a workspace's access tokens.",
320 ));
321 }
322 Ok(match self.get_workspace(SlugArgs { slug }).await? {
323 Some(workspace) => Outcome::Ok(workspace.id),
324 None => Outcome::fail(FailureCode::NotFound, "Workspace not found."),
325 })
326 }
327
328 pub async fn create_workspace_token(
329 &self,
330 a: CreateWorkspaceTokenArgs,
331 ) -> Result<Outcome<CreatedAccessToken>> {
332 let workspace_id = match self.owned_workspace(&a.actor, &a.slug).await? {
333 Outcome::Ok(id) => id,
334 Outcome::Fail(failure) => return Ok(Outcome::Fail(failure)),
335 };
336 if a.name.trim().is_empty() {
337 return Ok(Outcome::fail(
338 FailureCode::Invalid,
339 "Name the token after what will use it.",
340 ));
341 }
342 let existing = self
343 .tokens_where("access_tokens.workspace_id = ?", &workspace_id)
344 .await?;
345 if existing.len() >= MAX_TOKENS_PER_WORKSPACE {
346 return Ok(Outcome::fail(
347 FailureCode::Conflict,
348 "This workspace has the maximum number of access tokens. Delete one first.",
349 ));
350 }
351 let mut created = self
352 .mint(
353 Owner::Workspace {
354 id: &workspace_id,
355 created_by: Some(&a.actor.id),
356 },
357 &a.name,
358 None,
359 )
360 .await?;
361 created.info.created_by = Some(a.actor.username);
362 Ok(Outcome::Ok(created))
363 }
364
365 pub async fn remove_workspace_token(
366 &self,
367 a: RemoveWorkspaceTokenArgs,
368 ) -> Result<Outcome<bool>> {
369 let workspace_id = match self.owned_workspace(&a.actor, &a.slug).await? {
370 Outcome::Ok(id) => id,
371 Outcome::Fail(failure) => return Ok(Outcome::Fail(failure)),
372 };
373 self.db
374 .prepare("DELETE FROM access_tokens WHERE id = ? AND workspace_id = ?")
375 .bind(&[a.id.into(), workspace_id.into()])?
376 .run()
377 .await?;
378 Ok(Outcome::Ok(true))
379 }
380}