Move to using api:// for AAD Application "identifier uris" (#1243)

src/agent/onefuzz/src/auth.rs

@@ -111,19 +111,20 @@ impl ClientCredentials {
     }
 
     pub async fn access_token(&self) -> Result<AccessToken> {
-        let (authority, resource) = if let Some(domain) = &self.multi_tenant_domain {
+        let (authority, scope) = {
             let url = Url::parse(&self.resource.clone())?;
             let host = url.host_str().ok_or_else(|| {
                 anyhow::format_err!("resource URL does not have a host string: {}", url)
             })?;
-
+            if let Some(domain) = &self.multi_tenant_domain {
-            let instance: Vec<&str> = host.split('.').collect();
+                let instance: Vec<&str> = host.split('.').collect();
-            (
+                (
-                String::from("common"),
+                    String::from("common"),
-                format!("https://{}/{}/", &domain, instance[0]),
+                    format!("api://{}/{}/", &domain, instance[0]),
-            )
+                )
-        } else {
+            } else {
-            (self.tenant.clone(), self.resource.clone())
+                (self.tenant.clone(), format!("api://{}/", host))
+            }
         };
 
         let mut url = Url::parse("https://login.microsoftonline.com")?;
@@ -139,7 +140,7 @@ impl ClientCredentials {
                 ("client_secret", self.client_secret.expose_ref().to_string()),
                 ("grant_type", "client_credentials".into()),
                 ("tenant", authority),
-                ("scope", format!("{}.default", resource)),
+                ("scope", format!("{}.default", scope)),
             ])
             .send_retry_default()
             .await
@@ -180,15 +181,17 @@ const MANAGED_IDENTITY_URL: &str =
 
 impl ManagedIdentityCredentials {
     pub fn new(resource: String, multi_tenant_domain: Option<String>) -> Result<Self> {
-        let resource = if let Some(domain) = multi_tenant_domain.clone() {
+        let resource = {
             let resource_url = Url::parse(&resource)?;
             let host = resource_url.host_str().ok_or_else(|| {
                 anyhow::format_err!("resource URL does not have a host string: {}", resource_url)
             })?;
-            let instance: Vec<&str> = host.split('.').collect();
+            if let Some(domain) = multi_tenant_domain.clone() {
-            format!("https://{}/{}", domain, instance[0])
+                let instance: Vec<&str> = host.split('.').collect();
-        } else {
+                format!("api://{}/{}", domain, instance[0])
-            resource
+            } else {
+                format!("api://{}", host)
+            }
         };
 
         Ok(Self {
@@ -249,7 +252,7 @@ mod tests {
 
     #[test]
     fn test_managed_creds_with_valid_single_tenant() -> Result<()> {
-        let resource = "https://host-26.azurewebsites.net";
+        let resource = "api://host-26.azurewebsites.net";
 
         let managed_creds = ManagedIdentityCredentials::new(resource.to_string(), None)?;
 
@@ -259,7 +262,7 @@ mod tests {
 
     #[test]
     fn test_managed_creds_with_valid_multi_tenant_domain() -> Result<()> {
-        let resource = "https://host-26.azurewebsites.net";
+        let resource = "api://host-26.azurewebsites.net";
         let multi_tenant_domain = "mycloud.contoso.com";
 
         let managed_creds = ManagedIdentityCredentials::new(
@@ -267,7 +270,7 @@ mod tests {
             Some(multi_tenant_domain.to_string()),
         )?;
 
-        let expected = "https://mycloud.contoso.com/host-26";
+        let expected = "api://mycloud.contoso.com/host-26";
 
         assert_eq!(managed_creds.resource, expected);
 

src/cli/onefuzz/backend.py

@@ -177,10 +177,12 @@ class Backend:
         if self.config.tenant_domain:
             endpoint = urlparse(self.config.endpoint).netloc.split(".")[0]
             scopes = [
-                "https://" + self.config.tenant_domain + "/" + endpoint + "/.default"
+                f"api://{self.config.tenant_domain}/{endpoint}/.default",
+                f"https://{self.config.tenant_domain}/{endpoint}/.default",
             ]
         else:
-            scopes = [self.config.endpoint + "/.default"]
+            netloc = urlparse(self.config.endpoint).netloc
+            scopes = [f"api://{netloc}/.default", f"https://{netloc}/.default"]
 
         if self.config.client_secret:
             return self.client_secret(scopes)
@@ -194,7 +196,15 @@ class Backend:
                 client_credential=self.config.client_secret,
                 token_cache=self.token_cache,
             )
-        result = self.app.acquire_token_for_client(scopes=scopes)
+
+        for scope in scopes:
+            result = self.app.acquire_token_for_client(scopes=[scope])
+            # AADSTS500011: The resource principal named ... was not found in the tenant named ...
+            # This error is caused by a by mismatch between the identifierUr and the scope provided in the request.
+            if "error" in result and "AADSTS500011" in result["error_description"]:
+                LOGGER.warning(f"failed to get access token with scope {scope}")
+                continue
+
         if "error" in result:
             raise Exception(
                 "error: %s\n'%s'"
@@ -210,26 +220,47 @@ class Backend:
                 token_cache=self.token_cache,
             )
 
-        accounts = self.app.get_accounts()
+        for scope in scopes:
-        if accounts:
+            accounts = self.app.get_accounts()
-            access_token = self.app.acquire_token_silent(scopes, account=accounts[0])
+            if accounts:
-            if access_token:
+                access_token = self.app.acquire_token_silent(
-                return access_token
+                    [scope], account=accounts[0]
+                )
+                if access_token:
+                    return access_token
 
-        LOGGER.info("Attempting interactive device login")
+        for scope in scopes:
-        print("Please login", flush=True)
+            LOGGER.info("Attempting interactive device login")
+            print("Please login", flush=True)
 
-        flow = self.app.initiate_device_flow(scopes=scopes)
+            flow = self.app.initiate_device_flow(scopes=[scope])
-        check_msal_error(flow, ["user_code", "message"])
-        print(flow["message"], flush=True)
 
-        access_token = self.app.acquire_token_by_device_flow(flow)
+            check_msal_error(flow, ["user_code", "message"])
-        check_msal_error(access_token, ["access_token"])
+            # setting the expiration time to allow us to retry the interactive login with a new scope
+            flow["expires_at"] = int(time.time()) + 90  # 90 seconds from now
+            print(flow["message"], flush=True)
 
-        LOGGER.info("Interactive device authentication succeeded")
+            access_token = self.app.acquire_token_by_device_flow(flow)
-        print("Login succeeded", flush=True)
+            # AADSTS70016: OAuth 2.0 device flow error. Authorization is pending
-        self.save_cache()
+            # this happens when the intractive login request times out. This heppens when the login
-        return access_token
+            # fails because of a scope mismatch.
+            if (
+                "error" in access_token
+                and "AADSTS70016" in access_token["error_description"]
+            ):
+                LOGGER.warning(f"failed to get access token with scope {scope}")
+                continue
+            check_msal_error(access_token, ["access_token"])
+
+            LOGGER.info("Interactive device authentication succeeded")
+            print("Login succeeded", flush=True)
+            self.save_cache()
+            break
+
+        if access_token:
+            return access_token
+        else:
+            raise Exception("Failed to acquire token")
 
     def request(
         self,

src/deployment/azuredeploy.json

@@ -20,8 +20,8 @@
         "app_func_issuer": {
             "type": "string"
         },
-        "app_func_audience": {
+        "app_func_audiences": {
-            "type": "string"
+            "type": "array"
         },
         "multi_tenant_domain": {
             "type": "string"
@@ -283,9 +283,7 @@
                         "clientSecret": "[parameters('clientSecret')]",
                         "issuer": "[parameters('app_func_issuer')]",
                         "defaultProvider": "AzureActiveDirectory",
-                        "allowedAudiences": [
+                        "allowedAudiences": "[parameters('app_func_audiences')]",
-                            "[parameters('app_func_audience')]"
-                        ],
                         "isAadAutoProvisioned": false
                     }
                 },

src/deployment/deploy.py

@@ -310,7 +310,7 @@ class Client:
 
             params = ApplicationCreateParameters(
                 display_name=self.application_name,
-                identifier_uris=[url],
+                identifier_uris=[f"api://{self.application_name}.azurewebsites.net"],
                 reply_urls=[url + "/.auth/login/aad/callback"],
                 optional_claims=OptionalClaims(id_token=[], access_token=[]),
                 required_resource_access=[
@@ -362,6 +362,22 @@ class Client:
 
         else:
             app = existing[0]
+            if self.multi_tenant_domain:
+                api_id = "api://%s/%s" % (
+                    self.multi_tenant_domain,
+                    self.application_name,
+                )
+            else:
+                api_id = "api://%s.azurewebsites.net" % self.application_name
+
+            if api_id not in app.identifier_uris:
+                identifier_uris = app.identifier_uris
+                identifier_uris.append(api_id)
+                client.applications.patch(
+                    app.object_id,
+                    ApplicationUpdateParameters(identifier_uris=identifier_uris),
+                )
+
             existing_role_values = [app_role.value for app_role in app.app_roles]
             has_missing_roles = any(
                 [role.value not in existing_role_values for role in app_roles]
@@ -383,23 +399,12 @@ class Client:
                 )
 
         if self.multi_tenant_domain and app.sign_in_audience == "AzureADMyOrg":
-            url = "https://%s/%s" % (
-                self.multi_tenant_domain,
-                self.application_name,
-            )
-            client.applications.patch(
-                app.object_id, ApplicationUpdateParameters(identifier_uris=[url])
-            )
             set_app_audience(app.object_id, "AzureADMultipleOrgs")
         elif (
             not self.multi_tenant_domain
             and app.sign_in_audience == "AzureADMultipleOrgs"
         ):
             set_app_audience(app.object_id, "AzureADMyOrg")
-            url = "https://%s.azurewebsites.net" % self.application_name
-            client.applications.patch(
-                app.object_id, ApplicationUpdateParameters(identifier_uris=[url])
-            )
         else:
             logger.debug("No change to App Registration signInAudence setting")
 
@@ -471,20 +476,31 @@ class Client:
         if self.multi_tenant_domain:
             # clear the value in the Issuer Url field:
             # https://docs.microsoft.com/en-us/sharepoint/dev/spfx/use-aadhttpclient-enterpriseapi-multitenant
-            app_func_audience = "https://%s/%s" % (
+            app_func_audiences = [
-                self.multi_tenant_domain,
+                "api://%s/%s"
-                self.application_name,
+                % (
-            )
+                    self.multi_tenant_domain,
+                    self.application_name,
+                ),
+                "https://%s/%s"
+                % (
+                    self.multi_tenant_domain,
+                    self.application_name,
+                ),
+            ]
             app_func_issuer = ""
             multi_tenant_domain = {"value": self.multi_tenant_domain}
         else:
-            app_func_audience = "https://%s.azurewebsites.net" % self.application_name
+            app_func_audiences = [
+                "api://%s.azurewebsites.net" % self.application_name,
+                "https://%s.azurewebsites.net" % self.application_name,
+            ]
             tenant_oid = str(self.cli_config["authority"]).split("/")[-1]
             app_func_issuer = "https://sts.windows.net/%s/" % tenant_oid
             multi_tenant_domain = {"value": ""}
 
         params = {
-            "app_func_audience": {"value": app_func_audience},
+            "app_func_audiences": {"value": app_func_audiences},
             "name": {"value": self.application_name},
             "owner": {"value": self.owner},
             "clientId": {"value": self.results["client_id"]},