huskies: merge 936

server/src/chat/transport/whatsapp/mod.rs

@@ -181,8 +181,9 @@ pub async fn webhook_verify(
 /// Both providers expect a `200 OK` response, even on parse errors.
 ///
 /// For the `"meta"` provider, the `X-Hub-Signature-256` header is verified
-/// against the configured app secret (HMAC-SHA256).  Requests with a missing
-/// or invalid signature are rejected with `401`/`403` respectively.
+/// against the configured app secret (HMAC-SHA256).  For Twilio, the
+/// `X-Twilio-Signature` header is verified against the auth token.
+/// Requests with a missing or invalid signature are rejected with `403 Forbidden`.
 #[handler]
 pub async fn webhook_receive(
     req: &Request,
@@ -205,7 +206,7 @@ pub async fn webhook_receive(
         if signature.is_empty() {
             slog!("[whatsapp] Missing X-Hub-Signature-256 header; rejecting request");
             return Response::builder()
-                .status(StatusCode::UNAUTHORIZED)
+                .status(StatusCode::FORBIDDEN)
                 .body("Missing signature");
         }
         if !verify::verify_meta_signature(&ctx.app_secret, &bytes, signature) {
@@ -222,7 +223,7 @@ pub async fn webhook_receive(
         if signature.is_empty() {
             slog!("[whatsapp/twilio] Missing X-Twilio-Signature header; rejecting request");
             return Response::builder()
-                .status(StatusCode::UNAUTHORIZED)
+                .status(StatusCode::FORBIDDEN)
                 .body("Missing X-Twilio-Signature");
         }
         let url = reconstruct_request_url(req);
@@ -294,6 +295,173 @@ fn reconstruct_request_url(req: &Request) -> String {
 mod tests {
     use super::*;
 
+    // ── webhook_receive signature-verification handler tests ──────────
+
+    use crate::chat::transport::whatsapp::history::MessagingWindowTracker;
+    use poem::EndpointExt;
+    use std::fmt::Write as FmtWrite;
+    use std::sync::Arc;
+
+    struct NullTransport;
+
+    #[async_trait::async_trait]
+    impl crate::chat::ChatTransport for NullTransport {
+        async fn send_message(
+            &self,
+            _: &str,
+            _: &str,
+            _: &str,
+        ) -> Result<crate::chat::MessageId, String> {
+            Ok(String::new())
+        }
+        async fn edit_message(&self, _: &str, _: &str, _: &str, _: &str) -> Result<(), String> {
+            Ok(())
+        }
+        async fn send_typing(&self, _: &str, _: bool) -> Result<(), String> {
+            Ok(())
+        }
+    }
+
+    fn make_ctx(
+        provider: &str,
+        app_secret: &str,
+        twilio_auth_token: &str,
+    ) -> Arc<WhatsAppWebhookContext> {
+        let tmp = tempfile::tempdir().unwrap();
+        let services =
+            crate::services::Services::new_test(tmp.path().to_path_buf(), "Bot".to_string());
+        Arc::new(WhatsAppWebhookContext {
+            services,
+            verify_token: "tok".to_string(),
+            provider: provider.to_string(),
+            transport: Arc::new(NullTransport),
+            history: Arc::new(tokio::sync::Mutex::new(Default::default())),
+            history_size: 20,
+            window_tracker: Arc::new(MessagingWindowTracker::new()),
+            allowed_phones: vec![],
+            app_secret: app_secret.to_string(),
+            twilio_auth_token: twilio_auth_token.to_string(),
+        })
+    }
+
+    fn handler_app(
+        provider: &str,
+        app_secret: &str,
+        twilio_auth_token: &str,
+    ) -> impl poem::Endpoint {
+        let ctx = make_ctx(provider, app_secret, twilio_auth_token);
+        poem::Route::new()
+            .at("/webhook", poem::post(webhook_receive))
+            .data(ctx)
+    }
+
+    fn make_meta_sig(secret: &str, body: &[u8]) -> String {
+        use hmac::{Hmac, KeyInit, Mac};
+        use sha2::Sha256;
+        let mut mac = Hmac::<Sha256>::new_from_slice(secret.as_bytes()).unwrap();
+        mac.update(body);
+        let result = mac.finalize().into_bytes();
+        let mut hex = String::from("sha256=");
+        for b in &result {
+            write!(hex, "{b:02x}").unwrap();
+        }
+        hex
+    }
+
+    #[tokio::test]
+    async fn meta_missing_signature_returns_403() {
+        let app = handler_app("meta", "secret", "");
+        let cli = poem::test::TestClient::new(app);
+        let resp = cli
+            .post("/webhook")
+            .body(b"{\"entry\":[]}".to_vec())
+            .send()
+            .await;
+        assert_eq!(resp.0.status(), poem::http::StatusCode::FORBIDDEN);
+    }
+
+    #[tokio::test]
+    async fn meta_invalid_signature_returns_403() {
+        let app = handler_app("meta", "secret", "");
+        let cli = poem::test::TestClient::new(app);
+        let resp = cli
+            .post("/webhook")
+            .header(
+                "X-Hub-Signature-256",
+                "sha256=0000000000000000000000000000000000000000000000000000000000000000",
+            )
+            .body(b"{\"entry\":[]}".to_vec())
+            .send()
+            .await;
+        assert_eq!(resp.0.status(), poem::http::StatusCode::FORBIDDEN);
+    }
+
+    #[tokio::test]
+    async fn meta_valid_signature_passes() {
+        let body = b"{\"entry\":[]}";
+        let sig = make_meta_sig("secret", body);
+        let app = handler_app("meta", "secret", "");
+        let cli = poem::test::TestClient::new(app);
+        let resp = cli
+            .post("/webhook")
+            .header("X-Hub-Signature-256", sig)
+            .body(body.to_vec())
+            .send()
+            .await;
+        assert_eq!(resp.0.status(), poem::http::StatusCode::OK);
+    }
+
+    #[tokio::test]
+    async fn meta_no_secret_configured_skips_verification() {
+        // When app_secret is empty, signature checking is disabled (backwards-compat).
+        let app = handler_app("meta", "", "");
+        let cli = poem::test::TestClient::new(app);
+        let resp = cli
+            .post("/webhook")
+            .body(b"{\"entry\":[]}".to_vec())
+            .send()
+            .await;
+        assert_eq!(resp.0.status(), poem::http::StatusCode::OK);
+    }
+
+    #[tokio::test]
+    async fn twilio_missing_signature_returns_403() {
+        let app = handler_app("twilio", "", "twilio-token");
+        let cli = poem::test::TestClient::new(app);
+        let resp = cli
+            .post("/webhook")
+            .body(b"Body=hello&From=whatsapp%3A%2B15551234567".to_vec())
+            .send()
+            .await;
+        assert_eq!(resp.0.status(), poem::http::StatusCode::FORBIDDEN);
+    }
+
+    #[tokio::test]
+    async fn twilio_invalid_signature_returns_403() {
+        let app = handler_app("twilio", "", "twilio-token");
+        let cli = poem::test::TestClient::new(app);
+        let resp = cli
+            .post("/webhook")
+            .header("X-Twilio-Signature", "invalidsig==")
+            .body(b"Body=hello&From=whatsapp%3A%2B15551234567".to_vec())
+            .send()
+            .await;
+        assert_eq!(resp.0.status(), poem::http::StatusCode::FORBIDDEN);
+    }
+
+    #[tokio::test]
+    async fn twilio_no_auth_token_configured_skips_verification() {
+        // When twilio_auth_token is empty, signature checking is disabled (backwards-compat).
+        let app = handler_app("twilio", "", "");
+        let cli = poem::test::TestClient::new(app);
+        let resp = cli
+            .post("/webhook")
+            .body(b"Body=hello&From=whatsapp%3A%2B15551234567".to_vec())
+            .send()
+            .await;
+        assert_eq!(resp.0.status(), poem::http::StatusCode::OK);
+    }
+
     // ── Existing webhook / transport tests ────────────────────────────
 
     #[test]