tor-browser

helpers.js (23429B)

---

// Useful constants for working with COSE key objects
const cose_kty = 1;
const cose_kty_ec2 = 2;
const cose_alg = 3;
const cose_alg_ECDSA_w_SHA256 = -7;
const cose_alg_ECDSA_w_SHA512 = -36;
const cose_crv = -1;
const cose_crv_P256 = 1;
const cose_crv_x = -2;
const cose_crv_y = -3;

/**
* These are the default arguments that will be passed to navigator.credentials.create()
* unless modified by a specific test case
*/
var createCredentialDefaultArgs = {
   options: {
       publicKey: {
           // Relying Party:
           rp: {
               name: "Acme",
           },

           // User:
           user: {
               id: new Uint8Array(16), // Won't survive the copy, must be rebuilt
               name: "john.p.smith@example.com",
               displayName: "John P. Smith",
           },

           pubKeyCredParams: [{
               type: "public-key",
               alg: cose_alg_ECDSA_w_SHA256,
           }],

           authenticatorSelection: {
               requireResidentKey: false,
           },

           timeout: 60000, // 1 minute
           excludeCredentials: [] // No excludeList
       }
   }
};

/**
* These are the default arguments that will be passed to navigator.credentials.get()
* unless modified by a specific test case
*/
var getCredentialDefaultArgs = {
   options: {
       publicKey: {
           timeout: 60000
           // allowCredentials: [newCredential]
       }
   }
};

function createCredential(opts) {
   opts = opts || {};

   // set the default options
   var createArgs = cloneObject(createCredentialDefaultArgs);
   let challengeBytes = new Uint8Array(16);
   window.crypto.getRandomValues(challengeBytes);
   createArgs.options.publicKey.challenge = challengeBytes;
   createArgs.options.publicKey.user.id = new Uint8Array(16);

   // change the defaults with any options that were passed in
   extendObject(createArgs, opts);

   // create the credential, return the Promise
   return navigator.credentials.create(createArgs.options);
}

function assertCredential(credential) {
   var options = cloneObject(getCredentialDefaultArgs);
   let challengeBytes = new Uint8Array(16);
   window.crypto.getRandomValues(challengeBytes);
   options.challenge = challengeBytes;
   options.allowCredentials = [{type: 'public-key', id: credential.rawId}];
   return navigator.credentials.get({publicKey: options});
}

function createRandomString(len) {
   var text = "";
   var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
   for(var i = 0; i < len; i++) {
       text += possible.charAt(Math.floor(Math.random() * possible.length));
   }
   return text;
}


function ab2str(buf) {
   return String.fromCharCode.apply(null, new Uint8Array(buf));
}

// Useful constants for working with attestation data
const authenticator_data_user_present = 0x01;
const authenticator_data_user_verified = 0x04;
const authenticator_data_attested_cred_data = 0x40;
const authenticator_data_extension_data = 0x80;

function parseAuthenticatorData(buf) {
   if (buf.byteLength < 37) {
       throw new TypeError ("parseAuthenticatorData: buffer must be at least 37 bytes");
   }

   printHex ("authnrData", buf);

   var authnrData = new DataView(buf);
   var authnrDataObj = {};
   authnrDataObj.length = buf.byteLength;

   authnrDataObj.rpIdHash = new Uint8Array (buf.slice (0,32));
   authnrDataObj.rawFlags = authnrData.getUint8(32);
   authnrDataObj.counter = authnrData.getUint32(33, false);
   authnrDataObj.rawCounter = [];
   authnrDataObj.rawCounter[0] = authnrData.getUint8(33);
   authnrDataObj.rawCounter[1] = authnrData.getUint8(34);
   authnrDataObj.rawCounter[2] = authnrData.getUint8(35);
   authnrDataObj.rawCounter[3] = authnrData.getUint8(36);
   authnrDataObj.flags = {};

   authnrDataObj.flags.userPresent = (authnrDataObj.rawFlags&authenticator_data_user_present)?true:false;
   authnrDataObj.flags.userVerified = (authnrDataObj.rawFlags&authenticator_data_user_verified)?true:false;
   authnrDataObj.flags.attestedCredentialData = (authnrDataObj.rawFlags&authenticator_data_attested_cred_data)?true:false;
   authnrDataObj.flags.extensionData = (authnrDataObj.rawFlags&authenticator_data_extension_data)?true:false;

   return authnrDataObj;
}

/**
* TestCase
*
* A generic template for test cases
* Is intended to be overloaded with subclasses that override testObject, testFunction and argOrder
* The testObject is the default arguments for the testFunction
* The default testObject can be modified with the modify() method, making it easy to create new tests based on the default
* The testFunction is the target of the test and is called by the doIt() method. doIt() applies the testObject as arguments via toArgs()
* toArgs() uses argOrder to make sure the resulting array is in the right order of the arguments for the testFunction
*/
class TestCase {
   constructor() {
       this.testFunction = function() {
           throw new Error("Test Function not implemented");
       };
       this.testObject = {};
       this.argOrder = [];
       this.ctx = null;
   }

   /**
    * toObject
    *
    * return a copy of the testObject
    */
   toObject() {
       return JSON.parse(JSON.stringify(this.testObject)); // cheap clone
   }

   /**
    * toArgs
    *
    * converts test object to an array that is ordered in the same way as the arguments to the test function
    */
   toArgs() {
       var ret = [];
       // XXX, TODO: this won't necessarily produce the args in the right order
       for (let idx of this.argOrder) {
           ret.push(this.testObject[idx]);
       }
       return ret;
   }

   /**
    * modify
    *
    * update the internal object by a path / value combination
    * e.g. :
    * modify ("foo.bar", 3)
    * accepts three types of args:
    *    "foo.bar", 3
    *    {path: "foo.bar", value: 3}
    *    [{path: "foo.bar", value: 3}, ...]
    */
   modify(arg1, arg2) {
       var mods;

       // check for the two argument scenario
       if (typeof arg1 === "string" && arg2 !== undefined) {
           mods = {
               path: arg1,
               value: arg2
           };
       } else {
           mods = arg1;
       }

       // accept a single modification object instead of an array
       if (!Array.isArray(mods) && typeof mods === "object") {
           mods = [mods];
       }

       // iterate through each of the desired modifications, and call recursiveSetObject on them
       for (let idx in mods) {
           var mod = mods[idx];
           let paths = mod.path.split(".");
           recursiveSetObject(this.testObject, paths, mod.value);
       }

       // iterates through nested `obj` using the `pathArray`, creating the path if it doesn't exist
       // when the final leaf of the path is found, it is assigned the specified value
       function recursiveSetObject(obj, pathArray, value) {
           var currPath = pathArray.shift();
           if (typeof obj[currPath] !== "object") {
               obj[currPath] = {};
           }
           if (pathArray.length > 0) {
               return recursiveSetObject(obj[currPath], pathArray, value);
           }
           obj[currPath] = value;
       }

       return this;
   }

   /**
    * actually runs the test function with the supplied arguments
    */
   doIt() {
       if (typeof this.testFunction !== "function") {
           throw new Error("Test function not found");
       }

       return this.testFunction.call(this.ctx, ...this.toArgs());
   }

   /**
    * run the test function with the top-level properties of the test object applied as arguments
    * expects the test to pass, and then validates the results
    */
   testPasses(desc) {
       return this.doIt()
           .then((ret) => {
               // check the result
               this.validateRet(ret);
               return ret;
           });
   }

   /**
    * run the test function with the top-level properties of the test object applied as arguments
    * expects the test to fail
    */
   testFails(t, testDesc, expectedErr) {
       if (typeof expectedErr == "string") {
           return promise_rejects_dom(t, expectedErr, this.doIt(), "Expected  bad parameters to fail");
       }

       return promise_rejects_js(t, expectedErr, this.doIt(), "Expected bad parameters to fail");
   }

   /**
    * Runs the test that's implemented by the class by calling the doIt() function
    * @param  {String} desc                A description of the test being run
    * @param  [Error|String] expectedErr   A string matching an error type, such as "SecurityError" or an object with a .name value that is an error type string
    */
   runTest(desc, expectedErr) {
       promise_test((t) => {
           return Promise.resolve().then(() => {
               return this.testSetup();
           }).then(() => {
               if (expectedErr === undefined) {
                   return this.testPasses(desc);
               } else {
                   return this.testFails(t, desc, expectedErr);
               }
           }).then((res) => {
               return this.testTeardown(res);
           })
       }, desc)
   }

   /**
    * called before runTest
    * virtual method expected to be overridden by child class if needed
    */
   testSetup() {
       if (this.beforeTestFn) {
           this.beforeTestFn.call(this);
       }

       return Promise.resolve();
   }

   /**
    * Adds a callback function that gets called in the TestCase context
    * and within the testing process.
    */
   beforeTest(fn) {
       if (typeof fn !== "function") {
           throw new Error ("Tried to call non-function before test");
       }

       this.beforeTestFn = fn;

       return this;
   }

   /**
    * called after runTest
    * virtual method expected to be overridden by child class if needed
    */
   testTeardown(res) {
       if (this.afterTestFn) {
           this.afterTestFn.call(this, res);
       }

       return Promise.resolve();
   }

   /**
    * Adds a callback function that gets called in the TestCase context
    * and within the testing process. Good for validating results.
    */
   afterTest(fn) {
       if (typeof fn !== "function") {
           throw new Error ("Tried to call non-function after test");
       }

       this.afterTestFn = fn;

       return this;
   }

   /**
    * validates the value returned from the test function
    * virtual method expected to be overridden by child class
    */
   validateRet() {
       throw new Error("Not implemented");
   }
}

function cloneObject(o) {
   return JSON.parse(JSON.stringify(o));
}

function extendObject(dst, src) {
   Object.keys(src).forEach(function(key) {
       if (isSimpleObject(src[key]) && !isAbortSignal(src[key])) {
           dst[key] ||= {};
           extendObject(dst[key], src[key]);
       } else {
           dst[key] = src[key];
       }
   });
}

function isSimpleObject(o) {
   return (typeof o === "object" &&
       !Array.isArray(o) &&
       !(o instanceof ArrayBuffer) &&
       !(o instanceof Uint8Array));
}

function isAbortSignal(o) {
   return (o instanceof AbortSignal);
}

/**
* CreateCredentialTest
*
* tests the WebAuthn navigator.credentials.create() interface
*/
class CreateCredentialsTest extends TestCase {
   constructor() {
       // initialize the parent class
       super();

       // the function to be tested
       this.testFunction = navigator.credentials.create;
       // the context to call the test function with (i.e. - the 'this' object for the function)
       this.ctx = navigator.credentials;

       // the default object to pass to makeCredential, to be modified with modify() for various tests
       let challengeBytes = new Uint8Array(16);
       window.crypto.getRandomValues(challengeBytes);
       this.testObject = cloneObject(createCredentialDefaultArgs);
       // cloneObject can't clone the BufferSource in user.id, so let's recreate it.
       this.testObject.options.publicKey.user.id = new Uint8Array(16);
       this.testObject.options.publicKey.challenge = challengeBytes;

       // how to order the properties of testObject when passing them to makeCredential
       this.argOrder = [
           "options"
       ];

       // enable the constructor to modify the default testObject
       // would prefer to do this in the super class, but have to call super() before using `this.*`
       if (arguments.length) this.modify(...arguments);
   }

   validateRet(ret) {
       validatePublicKeyCredential(ret);
       validateAuthenticatorAttestationResponse(ret.response);
   }
}

/**
* GetCredentialsTest
*
* tests the WebAuthn navigator.credentials.get() interface
*/
class GetCredentialsTest extends TestCase {
   constructor(...args) {
       // initialize the parent class
       super();

       // the function to be tested
       this.testFunction = navigator.credentials.get;
       // the context to call the test function with (i.e. - the 'this' object for the function)
       this.ctx = navigator.credentials;

       // default arguments
       let challengeBytes = new Uint8Array(16);
       window.crypto.getRandomValues(challengeBytes);
       this.testObject = cloneObject(getCredentialDefaultArgs);
       this.testObject.options.publicKey.challenge = challengeBytes;

       // how to order the properties of testObject when passing them to makeCredential
       this.argOrder = [
           "options"
       ];

       this.credentialPromiseList = [];

       // set to true to pass an empty allowCredentials list to credentials.get
       this.isResidentKeyTest = false;

       // enable the constructor to modify the default testObject
       // would prefer to do this in the super class, but have to call super() before using `this.*`
       if (arguments.length) {
           if (args.cred instanceof Promise) this.credPromise = args.cred;
           else if (typeof args.cred === "object") this.credPromise = Promise.resolve(args.cred);
           delete args.cred;
           this.modify(...arguments);
       }
   }

   addCredential(arg) {
       // if a Promise was passed in, add it to the list
       if (arg instanceof Promise) {
           this.credentialPromiseList.push(arg);
           return this;
       }

       // if a credential object was passed in, convert it to a Promise for consistency
       if (typeof arg === "object") {
           this.credentialPromiseList.push(Promise.resolve(arg));
           return this;
       }

       // if no credential specified then create one
       var p = createCredential();
       this.credentialPromiseList.push(p);

       return this;
   }

   testSetup(desc) {
       if (!this.credentialPromiseList.length) {
           throw new Error("Attempting list without defining credential to test");
       }

       return Promise.all(this.credentialPromiseList)
           .then((credList) => {
               var idList = credList.map((cred) => {
                   return {
                       id: cred.rawId,
                       transports: ["usb", "nfc", "ble"],
                       type: "public-key"
                   };
               });
               if (!this.isResidentKeyTest) {
                   this.testObject.options.publicKey.allowCredentials = idList;
               }
               // return super.test(desc);
           })
           .catch((err) => {
               throw Error(err);
           });
   }

   validateRet(ret) {
       validatePublicKeyCredential(ret);
       validateAuthenticatorAssertionResponse(ret.response);
   }

   setIsResidentKeyTest(isResidentKeyTest) {
       this.isResidentKeyTest = isResidentKeyTest;
       return this;
   }
}

/**
* converts a uint8array to base64 url-safe encoding
* based on similar function in resources/utils.js
*/
function base64urlEncode(array) {
 let string = String.fromCharCode.apply(null, array);
 let result = btoa(string);
 return result.replace(/=+$/g, '').replace(/\+/g, "-").replace(/\//g, "_");
}
/**
* runs assertions against a PublicKeyCredential object to ensure it is properly formatted
*/
function validatePublicKeyCredential(cred) {
   // class
   assert_class_string(cred, "PublicKeyCredential", "Expected return to be instance of 'PublicKeyCredential' class");
   // id
   assert_idl_attribute(cred, "id", "should return PublicKeyCredential with id attribute");
   assert_readonly(cred, "id", "should return PublicKeyCredential with readonly id attribute");
   // rawId
   assert_idl_attribute(cred, "rawId", "should return PublicKeyCredential with rawId attribute");
   assert_readonly(cred, "rawId", "should return PublicKeyCredential with readonly rawId attribute");
   assert_equals(cred.id, base64urlEncode(new Uint8Array(cred.rawId)), "should return PublicKeyCredential with id attribute set to base64 encoding of rawId attribute");

   // type
   assert_idl_attribute(cred, "type", "should return PublicKeyCredential with type attribute");
   assert_equals(cred.type, "public-key", "should return PublicKeyCredential with type 'public-key'");
}

/**
* runs assertions against a AuthenticatorAttestationResponse object to ensure it is properly formatted
*/
function validateAuthenticatorAttestationResponse(attr) {
   // class
   assert_class_string(attr, "AuthenticatorAttestationResponse", "Expected credentials.create() to return instance of 'AuthenticatorAttestationResponse' class");

   // clientDataJSON
   assert_idl_attribute(attr, "clientDataJSON", "credentials.create() should return AuthenticatorAttestationResponse with clientDataJSON attribute");
   assert_readonly(attr, "clientDataJSON", "credentials.create() should return AuthenticatorAttestationResponse with readonly clientDataJSON attribute");
   // TODO: clientDataJSON() and make sure fields are correct

   // attestationObject
   assert_idl_attribute(attr, "attestationObject", "credentials.create() should return AuthenticatorAttestationResponse with attestationObject attribute");
   assert_readonly(attr, "attestationObject", "credentials.create() should return AuthenticatorAttestationResponse with readonly attestationObject attribute");
   // TODO: parseAuthenticatorData() and make sure flags are correct
}

/**
* runs assertions against a AuthenticatorAssertionResponse object to ensure it is properly formatted
*/
function validateAuthenticatorAssertionResponse(assert) {
   // class
   assert_class_string(assert, "AuthenticatorAssertionResponse", "Expected credentials.create() to return instance of 'AuthenticatorAssertionResponse' class");

   // clientDataJSON
   assert_idl_attribute(assert, "clientDataJSON", "credentials.get() should return AuthenticatorAssertionResponse with clientDataJSON attribute");
   assert_readonly(assert, "clientDataJSON", "credentials.get() should return AuthenticatorAssertionResponse with readonly clientDataJSON attribute");
   // TODO: clientDataJSON() and make sure fields are correct

   // signature
   assert_idl_attribute(assert, "signature", "credentials.get() should return AuthenticatorAssertionResponse with signature attribute");
   assert_readonly(assert, "signature", "credentials.get() should return AuthenticatorAssertionResponse with readonly signature attribute");

   // authenticatorData
   assert_idl_attribute(assert, "authenticatorData", "credentials.get() should return AuthenticatorAssertionResponse with authenticatorData attribute");
   assert_readonly(assert, "authenticatorData", "credentials.get() should return AuthenticatorAssertionResponse with readonly authenticatorData attribute");
   // TODO: parseAuthenticatorData() and make sure flags are correct
}

function defaultAuthenticatorArgs() {
 return {
   protocol: 'ctap1/u2f',
   transport: 'usb',
   hasResidentKey: false,
   hasUserVerification: false,
   isUserVerified: false,
 };
}

function standardSetup(cb, options = {}) {
 // Setup an automated testing environment if available.
 let authenticatorArgs = Object.assign(defaultAuthenticatorArgs(), options);
 window.test_driver.add_virtual_authenticator(authenticatorArgs)
     .then(authenticator => {
       cb();
       // XXX add a subtest to clean up the virtual authenticator since
       // testharness does not support waiting for promises on cleanup.
       promise_test(
           () =>
               window.test_driver.remove_virtual_authenticator(authenticator),
           'Clean up the test environment');
     })
     .catch(error => {
       if (error !==
           'error: Action add_virtual_authenticator not implemented') {
         throw error;
       }
       // The protocol is not available. Continue manually.
       cb();
     });
}

// virtualAuthenticatorPromiseTest runs |testCb| in a promise_test with a
// virtual authenticator set up before and destroyed after the test, if the
// virtual testing API is available. In manual tests, setup and teardown is
// skipped.
function virtualAuthenticatorPromiseTest(
   testCb, options = {}, name = 'Virtual Authenticator Test') {
 let authenticatorArgs = Object.assign(defaultAuthenticatorArgs(), options);
 promise_test(async t => {
   let authenticator;
   try {
     authenticator =
         await window.test_driver.add_virtual_authenticator(authenticatorArgs);
     t.add_cleanup(
         () => window.test_driver.remove_virtual_authenticator(authenticator));
   } catch (error) {
     if (error !== 'error: Action add_virtual_authenticator not implemented') {
       throw error;
     }
   }
   return testCb(t, authenticator);
 }, name);
}

function bytesEqual(a, b) {
 if (a instanceof ArrayBuffer) {
   a = new Uint8Array(a);
 }
 if (b instanceof ArrayBuffer) {
   b = new Uint8Array(b);
 }
 if (a.byteLength != b.byteLength) {
   return false;
 }
 for (let i = 0; i < a.byteLength; i++) {
   if (a[i] != b[i]) {
     return false;
   }
 }
 return true;
}

// Compares two PublicKeyCredentialUserEntity objects.
function userEntityEquals(a, b) {
 return bytesEqual(a.id, b.id) && a.name == b.name && a.displayName == b.displayName;
}

// Asserts that `actual` and `expected`, which are both JSON types, are equal.
// The object key order is ignored for comparison.
function assertJsonEquals(actual, expected, optMsg) {
 // Returns a copy of `jsonObj`, which must be a JSON type, with object keys
 // recursively sorted in lexicographic order; or simply `jsonObj` if it is not
 // an instance of Object.
 function deepSortKeys(jsonObj) {
   if (jsonObj instanceof Array) {
     return Array.from(jsonObj, (x) => { return deepSortKeys(x); })
   }
   if (typeof jsonObj !== 'object' || jsonObj === null ||
     jsonObj.__proto__.constructor !== Object ||
     Object.keys(jsonObj).length === 0) {
     return jsonObj;
   }
   return Object.keys(jsonObj).sort().reduce((acc, key) => {
     acc[key] = deepSortKeys(jsonObj[key]);
     return acc;
   }, {});
 }

 assert_equals(
   JSON.stringify(deepSortKeys(actual)),
   JSON.stringify(deepSortKeys(expected)), optMsg);
}