OIDC: navigate to authorization endpoint (#3499)

* utils for authorization step in OIDC code grant

* tidy

* completeAuthorizationCodeGrant util functions

* response_mode=query

* add scope to bearertoken type

* add is_guest to whoami response type

* doc comments

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

* use shimmed TextEncoder

* fetchMockJest -> fetchMock

* comment

* bearertokenresponse

* test for lowercase bearer

* handle lowercase token_type

---------

Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>

spec/unit/oidc/authorize.spec.ts

@@ -0,0 +1,209 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import fetchMock from "fetch-mock-jest";
+
+import { Method } from "../../../src";
+import * as crypto from "../../../src/crypto/crypto";
+import { logger } from "../../../src/logger";
+import {
+    completeAuthorizationCodeGrant,
+    generateAuthorizationParams,
+    generateAuthorizationUrl,
+} from "../../../src/oidc/authorize";
+import { OidcError } from "../../../src/oidc/error";
+
+// save for resetting mocks
+const realSubtleCrypto = crypto.subtleCrypto;
+
+describe("oidc authorization", () => {
+    const issuer = "https://auth.com/";
+    const authorizationEndpoint = "https://auth.com/authorization";
+    const tokenEndpoint = "https://auth.com/token";
+    const delegatedAuthConfig = {
+        issuer,
+        registrationEndpoint: issuer + "registration",
+        authorizationEndpoint: issuer + "auth",
+        tokenEndpoint,
+    };
+    const clientId = "xyz789";
+    const baseUrl = "https://test.com";
+
+    beforeAll(() => {
+        jest.spyOn(logger, "warn");
+    });
+
+    afterEach(() => {
+        // @ts-ignore reset any ugly mocking we did
+        crypto.subtleCrypto = realSubtleCrypto;
+    });
+
+    it("should generate authorization params", () => {
+        const result = generateAuthorizationParams({ redirectUri: baseUrl });
+
+        expect(result.redirectUri).toEqual(baseUrl);
+
+        // random strings
+        expect(result.state.length).toEqual(8);
+        expect(result.nonce.length).toEqual(8);
+        expect(result.codeVerifier.length).toEqual(64);
+
+        const expectedScope =
+            "openid urn:matrix:org.matrix.msc2967.client:api:* urn:matrix:org.matrix.msc2967.client:device:";
+        expect(result.scope.startsWith(expectedScope)).toBeTruthy();
+        // deviceId of 10 characters is appended to the device scope
+        expect(result.scope.length).toEqual(expectedScope.length + 10);
+    });
+
+    describe("generateAuthorizationUrl()", () => {
+        it("should generate url with correct parameters", async () => {
+            // test the no crypto case here
+            // @ts-ignore mocking
+            crypto.subtleCrypto = undefined;
+
+            const authorizationParams = generateAuthorizationParams({ redirectUri: baseUrl });
+            const authUrl = new URL(
+                await generateAuthorizationUrl(authorizationEndpoint, clientId, authorizationParams),
+            );
+
+            expect(authUrl.searchParams.get("response_mode")).toEqual("query");
+            expect(authUrl.searchParams.get("response_type")).toEqual("code");
+            expect(authUrl.searchParams.get("client_id")).toEqual(clientId);
+            expect(authUrl.searchParams.get("code_challenge_method")).toEqual("S256");
+            expect(authUrl.searchParams.get("scope")).toEqual(authorizationParams.scope);
+            expect(authUrl.searchParams.get("state")).toEqual(authorizationParams.state);
+            expect(authUrl.searchParams.get("nonce")).toEqual(authorizationParams.nonce);
+
+            // crypto not available, plain text code_challenge is used
+            expect(authUrl.searchParams.get("code_challenge")).toEqual(authorizationParams.codeVerifier);
+            expect(logger.warn).toHaveBeenCalledWith(
+                "A secure context is required to generate code challenge. Using plain text code challenge",
+            );
+        });
+
+        it("uses a s256 code challenge when crypto is available", async () => {
+            jest.spyOn(crypto.subtleCrypto, "digest");
+            const authorizationParams = generateAuthorizationParams({ redirectUri: baseUrl });
+            const authUrl = new URL(
+                await generateAuthorizationUrl(authorizationEndpoint, clientId, authorizationParams),
+            );
+
+            const codeChallenge = authUrl.searchParams.get("code_challenge");
+            expect(crypto.subtleCrypto.digest).toHaveBeenCalledWith("SHA-256", expect.any(Object));
+
+            // didn't use plain text code challenge
+            expect(authorizationParams.codeVerifier).not.toEqual(codeChallenge);
+            expect(codeChallenge).toBeTruthy();
+        });
+    });
+
+    describe("completeAuthorizationCodeGrant", () => {
+        const codeVerifier = "abc123";
+        const redirectUri = baseUrl;
+        const code = "auth_code_xyz";
+        const validBearerTokenResponse = {
+            token_type: "Bearer",
+            access_token: "test_access_token",
+            refresh_token: "test_refresh_token",
+            expires_in: 12345,
+        };
+
+        beforeEach(() => {
+            fetchMock.mockClear();
+            fetchMock.resetBehavior();
+
+            fetchMock.post(tokenEndpoint, {
+                status: 200,
+                body: JSON.stringify(validBearerTokenResponse),
+            });
+        });
+
+        it("should make correct request to the token endpoint", async () => {
+            await completeAuthorizationCodeGrant(code, { clientId, codeVerifier, redirectUri, delegatedAuthConfig });
+
+            expect(fetchMock).toHaveBeenCalledWith(tokenEndpoint, {
+                method: Method.Post,
+                headers: { "Content-Type": "application/x-www-form-urlencoded" },
+                body: `grant_type=authorization_code&client_id=${clientId}&code_verifier=${codeVerifier}&redirect_uri=https%3A%2F%2Ftest.com&code=${code}`,
+            });
+        });
+
+        it("should return with valid bearer token", async () => {
+            const result = await completeAuthorizationCodeGrant(code, {
+                clientId,
+                codeVerifier,
+                redirectUri,
+                delegatedAuthConfig,
+            });
+
+            expect(result).toEqual(validBearerTokenResponse);
+        });
+
+        it("should return with valid bearer token where token_type is lowercase", async () => {
+            const tokenResponse = {
+                ...validBearerTokenResponse,
+                token_type: "bearer",
+            };
+            fetchMock.post(
+                tokenEndpoint,
+                {
+                    status: 200,
+                    body: JSON.stringify(tokenResponse),
+                },
+                { overwriteRoutes: true },
+            );
+
+            const result = await completeAuthorizationCodeGrant(code, {
+                clientId,
+                codeVerifier,
+                redirectUri,
+                delegatedAuthConfig,
+            });
+
+            // results in token that uses 'Bearer' token type
+            expect(result).toEqual(validBearerTokenResponse);
+            expect(result.token_type).toEqual("Bearer");
+        });
+
+        it("should throw with code exchange failed error when request fails", async () => {
+            fetchMock.post(
+                tokenEndpoint,
+                {
+                    status: 500,
+                },
+                { overwriteRoutes: true },
+            );
+            await expect(() =>
+                completeAuthorizationCodeGrant(code, { clientId, codeVerifier, redirectUri, delegatedAuthConfig }),
+            ).rejects.toThrow(new Error(OidcError.CodeExchangeFailed));
+        });
+
+        it("should throw invalid token error when token is invalid", async () => {
+            const invalidBearerTokenResponse = {
+                ...validBearerTokenResponse,
+                access_token: null,
+            };
+            fetchMock.post(
+                tokenEndpoint,
+                { status: 200, body: JSON.stringify(invalidBearerTokenResponse) },
+                { overwriteRoutes: true },
+            );
+            await expect(() =>
+                completeAuthorizationCodeGrant(code, { clientId, codeVerifier, redirectUri, delegatedAuthConfig }),
+            ).rejects.toThrow(new Error(OidcError.InvalidBearerTokenResponse));
+        });
+    });
+});

src/client.ts

@@ -871,6 +871,7 @@ export interface TimestampToEventResponse {
 interface IWhoamiResponse {
     user_id: string;
     device_id?: string;
+    is_guest?: boolean;
 }
 /* eslint-enable camelcase */