1use super::{
2 db::{self, UserId},
3 errors::TideResultExt,
4};
5use crate::{github, AppState, Request, RequestExt as _};
6use anyhow::{anyhow, Context};
7use async_trait::async_trait;
8pub use oauth2::basic::BasicClient as Client;
9use oauth2::{
10 AuthUrl, AuthorizationCode, ClientId, CsrfToken, PkceCodeChallenge, RedirectUrl,
11 TokenResponse as _, TokenUrl,
12};
13use rand::thread_rng;
14use scrypt::{
15 password_hash::{PasswordHash, PasswordHasher, PasswordVerifier, SaltString},
16 Scrypt,
17};
18use serde::{Deserialize, Serialize};
19use std::{borrow::Cow, convert::TryFrom, sync::Arc};
20use surf::{StatusCode, Url};
21use tide::Server;
22use zrpc::auth as zed_auth;
23
24static CURRENT_GITHUB_USER: &'static str = "current_github_user";
25static GITHUB_AUTH_URL: &'static str = "https://github.com/login/oauth/authorize";
26static GITHUB_TOKEN_URL: &'static str = "https://github.com/login/oauth/access_token";
27
28#[derive(Serialize)]
29pub struct User {
30 pub github_login: String,
31 pub avatar_url: String,
32 pub is_insider: bool,
33 pub is_admin: bool,
34}
35
36pub struct VerifyToken;
37
38#[async_trait]
39impl tide::Middleware<Arc<AppState>> for VerifyToken {
40 async fn handle(
41 &self,
42 mut request: Request,
43 next: tide::Next<'_, Arc<AppState>>,
44 ) -> tide::Result {
45 let mut auth_header = request
46 .header("Authorization")
47 .ok_or_else(|| anyhow!("no authorization header"))?
48 .last()
49 .as_str()
50 .split_whitespace();
51
52 let user_id = UserId(
53 auth_header
54 .next()
55 .ok_or_else(|| anyhow!("missing user id in authorization header"))?
56 .parse()?,
57 );
58 let access_token = auth_header
59 .next()
60 .ok_or_else(|| anyhow!("missing access token in authorization header"))?;
61
62 let state = request.state().clone();
63
64 let mut credentials_valid = false;
65 for password_hash in state.db.get_access_token_hashes(user_id).await? {
66 if verify_access_token(&access_token, &password_hash)? {
67 credentials_valid = true;
68 break;
69 }
70 }
71
72 if credentials_valid {
73 request.set_ext(user_id);
74 Ok(next.run(request).await)
75 } else {
76 let mut response = tide::Response::new(StatusCode::Unauthorized);
77 response.set_body("invalid credentials");
78 Ok(response)
79 }
80 }
81}
82
83#[async_trait]
84pub trait RequestExt {
85 async fn current_user(&self) -> tide::Result<Option<User>>;
86}
87
88#[async_trait]
89impl RequestExt for Request {
90 async fn current_user(&self) -> tide::Result<Option<User>> {
91 if let Some(details) = self.session().get::<github::User>(CURRENT_GITHUB_USER) {
92 let user = self.db().get_user_by_github_login(&details.login).await?;
93 Ok(Some(User {
94 github_login: details.login,
95 avatar_url: details.avatar_url,
96 is_insider: user.is_some(),
97 is_admin: user.map_or(false, |user| user.admin),
98 }))
99 } else {
100 Ok(None)
101 }
102 }
103}
104
105pub fn build_client(client_id: &str, client_secret: &str) -> Client {
106 Client::new(
107 ClientId::new(client_id.to_string()),
108 Some(oauth2::ClientSecret::new(client_secret.to_string())),
109 AuthUrl::new(GITHUB_AUTH_URL.into()).unwrap(),
110 Some(TokenUrl::new(GITHUB_TOKEN_URL.into()).unwrap()),
111 )
112}
113
114pub fn add_routes(app: &mut Server<Arc<AppState>>) {
115 app.at("/sign_in").get(get_sign_in);
116 app.at("/sign_out").post(post_sign_out);
117 app.at("/auth_callback").get(get_auth_callback);
118}
119
120#[derive(Debug, Deserialize)]
121struct NativeAppSignInParams {
122 native_app_port: String,
123 native_app_public_key: String,
124}
125
126async fn get_sign_in(mut request: Request) -> tide::Result {
127 let (pkce_challenge, pkce_verifier) = PkceCodeChallenge::new_random_sha256();
128
129 request
130 .session_mut()
131 .insert("pkce_verifier", pkce_verifier)?;
132
133 let mut redirect_url = Url::parse(&format!(
134 "{}://{}/auth_callback",
135 request
136 .header("X-Forwarded-Proto")
137 .and_then(|values| values.get(0))
138 .map(|value| value.as_str())
139 .unwrap_or("http"),
140 request.host().unwrap()
141 ))?;
142
143 let app_sign_in_params: Option<NativeAppSignInParams> = request.query().ok();
144 if let Some(query) = app_sign_in_params {
145 redirect_url
146 .query_pairs_mut()
147 .clear()
148 .append_pair("native_app_port", &query.native_app_port)
149 .append_pair("native_app_public_key", &query.native_app_public_key);
150 }
151
152 let (auth_url, csrf_token) = request
153 .state()
154 .auth_client
155 .authorize_url(CsrfToken::new_random)
156 .set_redirect_uri(Cow::Owned(RedirectUrl::from_url(redirect_url)))
157 .set_pkce_challenge(pkce_challenge)
158 .url();
159
160 request
161 .session_mut()
162 .insert("auth_csrf_token", csrf_token)?;
163
164 Ok(tide::Redirect::new(auth_url).into())
165}
166
167async fn get_auth_callback(mut request: Request) -> tide::Result {
168 #[derive(Debug, Deserialize)]
169 struct Query {
170 code: String,
171 state: String,
172
173 #[serde(flatten)]
174 native_app_sign_in_params: Option<NativeAppSignInParams>,
175 }
176
177 let query: Query = request.query()?;
178
179 let pkce_verifier = request
180 .session()
181 .get("pkce_verifier")
182 .ok_or_else(|| anyhow!("could not retrieve pkce_verifier from session"))?;
183
184 let csrf_token = request
185 .session()
186 .get::<CsrfToken>("auth_csrf_token")
187 .ok_or_else(|| anyhow!("could not retrieve auth_csrf_token from session"))?;
188
189 if &query.state != csrf_token.secret() {
190 return Err(anyhow!("csrf token does not match").into());
191 }
192
193 let github_access_token = request
194 .state()
195 .auth_client
196 .exchange_code(AuthorizationCode::new(query.code))
197 .set_pkce_verifier(pkce_verifier)
198 .request_async(oauth2_surf::http_client)
199 .await
200 .context("failed to exchange oauth code")?
201 .access_token()
202 .secret()
203 .clone();
204
205 let user_details = request
206 .state()
207 .github_client
208 .user(github_access_token)
209 .details()
210 .await
211 .context("failed to fetch user")?;
212
213 let user = request
214 .db()
215 .get_user_by_github_login(&user_details.login)
216 .await?;
217
218 request
219 .session_mut()
220 .insert(CURRENT_GITHUB_USER, user_details.clone())?;
221
222 // When signing in from the native app, generate a new access token for the current user. Return
223 // a redirect so that the user's browser sends this access token to the locally-running app.
224 if let Some((user, app_sign_in_params)) = user.zip(query.native_app_sign_in_params) {
225 let access_token = create_access_token(request.db(), user.id).await?;
226 let native_app_public_key =
227 zed_auth::PublicKey::try_from(app_sign_in_params.native_app_public_key.clone())
228 .context("failed to parse app public key")?;
229 let encrypted_access_token = native_app_public_key
230 .encrypt_string(&access_token)
231 .context("failed to encrypt access token with public key")?;
232
233 return Ok(tide::Redirect::new(&format!(
234 "http://127.0.0.1:{}?user_id={}&access_token={}",
235 app_sign_in_params.native_app_port, user.id.0, encrypted_access_token,
236 ))
237 .into());
238 }
239
240 Ok(tide::Redirect::new("/").into())
241}
242
243async fn post_sign_out(mut request: Request) -> tide::Result {
244 request.session_mut().remove(CURRENT_GITHUB_USER);
245 Ok(tide::Redirect::new("/").into())
246}
247
248pub async fn create_access_token(db: &db::Db, user_id: UserId) -> tide::Result<String> {
249 let access_token = zed_auth::random_token();
250 let access_token_hash =
251 hash_access_token(&access_token).context("failed to hash access token")?;
252 db.create_access_token_hash(user_id, access_token_hash)
253 .await?;
254 Ok(access_token)
255}
256
257fn hash_access_token(token: &str) -> tide::Result<String> {
258 // Avoid slow hashing in debug mode.
259 let params = if cfg!(debug_assertions) {
260 scrypt::Params::new(1, 1, 1).unwrap()
261 } else {
262 scrypt::Params::recommended()
263 };
264
265 Ok(Scrypt
266 .hash_password(
267 token.as_bytes(),
268 None,
269 params,
270 &SaltString::generate(thread_rng()),
271 )?
272 .to_string())
273}
274
275pub fn verify_access_token(token: &str, hash: &str) -> tide::Result<bool> {
276 let hash = PasswordHash::new(hash)?;
277 Ok(Scrypt.verify_password(token.as_bytes(), &hash).is_ok())
278}