Add check on password complexity by using a backend call without divulging the list being checked against.

src/components/join-flow/username-step.jsx

@@ -24,6 +24,7 @@ class UsernameStep extends React.Component {
             'handleSetUsernameRef',
             'handleValidSubmit',
             'validatePasswordIfPresent',
+            'validatePasswordRemotelyWithCache',
             'validatePasswordConfirmIfPresent',
             'validateUsernameIfPresent',
             'validateUsernameRemotelyWithCache',
@@ -32,9 +33,10 @@ class UsernameStep extends React.Component {
         this.state = {
             focused: null
         };
-        // simple object to memoize remote requests for usernames.
+        // memoize remote requests for username check and password weakness
         // keeps us from submitting multiple requests for same data.
         this.usernameRemoteCache = Object.create(null);
+        this.passwordRemoteCache = Object.create(null);
     }
     componentDidMount () {
         // Send info to analytics when we aren't on the standalone page.
@@ -92,12 +94,37 @@ class UsernameStep extends React.Component {
             }
         );
     }
+    // memoize remote requests for weak password check
+    validatePasswordRemotelyWithCache (password) {
+        if (typeof this.passwordRemoteCache[password] === 'object') {
+            return Promise.resolve(this.passwordRemoteCache[password]);
+        }
+        // password is not in our cache
+        return validate.validatePasswordRemotely(password).then(
+            remoteResult => {
+                // cache result, if it successfully heard back from server
+                if (remoteResult.requestSucceeded) {
+                    this.passwordRemoteCache[password] = remoteResult;
+                }
+                return remoteResult;
+            }
+        );
+    }
     validatePasswordIfPresent (password, username) {
         if (!password) return null; // skip validation if password is blank; null indicates valid
-        const localResult = validate.validatePassword(password, username);
-        if (localResult.valid) return null;
-        return this.props.intl.formatMessage({id: localResult.errMsgId});
-    }
+        // if password is not blank, run both local and remote validations
+        const localResult = validate.validatePasswordLocally(password, username);
+        return this.validatePasswordRemotelyWithCache(password).then(
+            remoteResult => {
+                if (localResult.valid === false) { // defer to local check first
+                    return this.props.intl.formatMessage({id: localResult.errMsgId});
+                } else if (remoteResult.valid === false) {
+                    return this.props.intl.formatMessage({id: remoteResult.errMsgId});
+                }
+                return null;
+            } // remoteResult
+        ); // validatePasswordRemotelyWithCache
+    } // validatePasswordIfPresent
     validatePasswordConfirmIfPresent (password, passwordConfirm) {
         if (!passwordConfirm) return null; // allow blank password if not submitting yet
         const localResult = validate.validatePasswordConfirm(password, passwordConfirm);
@@ -114,7 +141,7 @@ class UsernameStep extends React.Component {
         if (!usernameResult.valid) {
             errors.username = this.props.intl.formatMessage({id: usernameResult.errMsgId});
         }
-        const passwordResult = validate.validatePassword(values.password, values.username);
+        const passwordResult = validate.validatePasswordLocally(values.password, values.username);
         if (!passwordResult.valid) {
             errors.password = this.props.intl.formatMessage({id: passwordResult.errMsgId});
         }

src/lib/validate.js

@@ -54,7 +54,7 @@ module.exports.validateUsernameRemotely = username => (
  * @param  {string} username     username value to compare
  * @return {object}              {valid: boolean, errMsgId: string}
  */
-module.exports.validatePassword = (password, username) => {
+module.exports.validatePasswordLocally = (password, username) => {
     if (!password) {
         return {valid: false, errMsgId: 'general.required'};
     // Using Array.from(string).length, instead of string.length, improves unicode
@@ -67,7 +67,7 @@ module.exports.validatePassword = (password, username) => {
     // https://stackoverflow.com/a/54370584/2308190
     } else if (Array.from(password).length < 6) {
         return {valid: false, errMsgId: 'registration.validationPasswordLength'};
-    } else if (password === 'password') {
+    } else if (password.toLowerCase() === 'password') {
         return {valid: false, errMsgId: 'registration.validationPasswordNotEquals'};
     } else if (username && password === username) {
         return {valid: false, errMsgId: 'registration.validationPasswordNotUsername'};
@@ -75,6 +75,43 @@ module.exports.validatePassword = (password, username) => {
     return {valid: true};
 };
 
+module.exports.validatePasswordRemotely = password => (
+    new Promise(resolve => {
+        api({
+            method: 'POST',
+            uri: `/accounts/checkpassword`,
+            json: {
+                password: `${password}`
+            }
+        }, (err, body, res) => {
+            if (err || res.statusCode !== 200) {
+                return resolve({
+                    requestSucceeded: false,
+                    valid: false,
+                    errMsgId: 'general.error'
+                });
+            }
+            let msg = '';
+            if (body && body.msg) msg = body.msg;
+            else if (body && body[0]) msg = body[0].msg;
+            switch (msg) {
+            case 'valid password':
+                return resolve({
+                    requestSucceeded: true,
+                    valid: true
+                });
+            case 'valid password':
+            default:
+                return resolve({
+                    requestSucceeded: true,
+                    valid: false,
+                    errMsgId: 'registration.validationPasswordNotEquals'
+                });
+            }; // switch
+        }); // api
+    }) // promise
+);
+
 module.exports.validatePasswordConfirm = (password, passwordConfirm) => {
     if (!passwordConfirm) {
         return {valid: false, errMsgId: 'general.required'};

test/unit/lib/validate.test.js

@@ -55,38 +55,38 @@ describe('unit test lib/validate.js', () => {
     test('validate password existence', () => {
         let response;
         expect(typeof validate.validatePassword).toBe('function');
-        response = validate.validatePassword('abcdef');
+        response = validate.validatePasswordLocally('abcdef');
         expect(response).toEqual({valid: true});
-        response = validate.validatePassword('');
+        response = validate.validatePasswordLocally('');
         expect(response).toEqual({valid: false, errMsgId: 'general.required'});
     });
 
     test('validate password length', () => {
         let response;
-        response = validate.validatePassword('abcdefghijklmnopqrst');
+        response = validate.validatePasswordLocally('abcdefghijklmnopqrst');
         expect(response).toEqual({valid: true});
-        response = validate.validatePassword('abcde');
+        response = validate.validatePasswordLocally('abcde');
         expect(response).toEqual({valid: false, errMsgId: 'registration.validationPasswordLength'});
-        response = validate.validatePassword('😺');
+        response = validate.validatePasswordLocally('😺');
         expect(response).toEqual({valid: false, errMsgId: 'registration.validationPasswordLength'});
-        response = validate.validatePassword('😺🦆🐝');
+        response = validate.validatePasswordLocally('😺🦆🐝');
         expect(response).toEqual({valid: false, errMsgId: 'registration.validationPasswordLength'});
-        response = validate.validatePassword('😺🦆🐝🐮🐠');
+        response = validate.validatePasswordLocally('😺🦆🐝🐮🐠');
         expect(response).toEqual({valid: false, errMsgId: 'registration.validationPasswordLength'});
-        response = validate.validatePassword('😺🦆🐝🐮🐠🐻');
+        response = validate.validatePasswordLocally('😺🦆🐝🐮🐠🐻');
         expect(response).toEqual({valid: true});
     });
 
     test('validate password cannot be "password"', () => {
-        const response = validate.validatePassword('password');
+        const response = validate.validatePasswordLocally('password');
         expect(response).toEqual({valid: false, errMsgId: 'registration.validationPasswordNotEquals'});
     });
 
     test('validate password cannot be same as username', () => {
         let response;
-        response = validate.validatePassword('abcdefg', 'abcdefg');
+        response = validate.validatePasswordLocally('abcdefg', 'abcdefg');
         expect(response).toEqual({valid: false, errMsgId: 'registration.validationPasswordNotUsername'});
-        response = validate.validatePassword('abcdefg', 'abcdefG');
+        response = validate.validatePasswordLocally('abcdefg', 'abcdefG');
         expect(response).toEqual({valid: true});
     });