MksDdn Reddy Auth provides OTP-based authentication with:
<ul>
<li>WordPress cookie session login for the frontend (shortcode, or REST with <code>issue_session: true</code>).</li>
<li>Optional Bearer token issuing for REST clients (<code>issue_token: true</code>; cookie not set by default on REST login).</li>
<li>Rate limiting and one-time OTP verification.</li>
<li>Optional site and REST API protection for unauthenticated visitors.</li>
<li>Optional allowed request sources (Origin/Referer) for plugin REST endpoints.</li>
</ul>
The plugin maps each Reddy ID to a WordPress user and can create an account automatically on first successful login.
<h3>Getting Started</h3>
<h4>1. Configure the Reddy bot token</h4>
For production, define the token in <code>wp-config.php</code>:
<pre><code>define( 'MKSDDN_REDDY_BOT_TOKEN', 'your-bot-token' );
</code></pre>
For local development you can store the token in Settings > Reddy Auth instead. Use Bot connection test to verify delivery to a Reddy user.
<h4>2. Set up the login page</h4>
Create a WordPress page (for example, <code>/login/</code>) and insert:
<pre><code>[mksddn_reddy_login]
</code></pre>
Users enter their Reddy ID, receive a one-time code in Reddy, and sign in through the form.
<h4>3. Review protection settings</h4>
By default, both protection options are disabled so your site stays accessible after activation. Enable them only after the login page is configured:
<ul>
<li>Protect site content — redirects unauthenticated visitors to the login page.</li>
<li>Protect all REST API content — returns <code>401</code> for protected REST routes.</li>
</ul>
Public auth routes remain available without login:
<ul>
<li><code>POST /wp-json/mksddn-reddy-auth/v1/auth/send-code</code></li>
<li><code>POST /wp-json/mksddn-reddy-auth/v1/auth/login</code></li>
<li><code>GET /wp-json/mksddn-reddy-auth/v1/auth/intent-status</code></li>
<li><code>POST /wp-json/mksddn-reddy-auth/v1/auth/intent-status</code></li>
<li><code>POST /wp-json/mksddn-reddy-auth/v1/auth/complete-intent</code></li>
</ul>
Webhook callback route is also public for BotMother integration:
<ul>
<li><code>POST /wp-json/mksddn-reddy-auth/v1/auth/button-callback</code></li>
</ul>
<h4>4. Use REST API for headless clients</h4>
Typical flow:
<ol>
<li><code>POST /auth/send-code</code> with <code>{ "reddy_id": "123456" }</code></li>
<li><code>POST /auth/login</code> with <code>{ "reddy_id": "123456", "code": "111111", "issue_token": true }</code> for headless clients. Add <code>"issue_session": true</code> only when the browser must also receive a WordPress cookie (same-origin SPA).</li>
<li>Call protected REST routes with <code>Authorization: Bearer <token></code>.</li>
<li><code>GET /auth/me</code> to read the current user (Bearer or cookie session).</li>
<li><code>POST /auth/logout</code> to end the cookie session and revoke the Bearer token when provided.</li>
</ol>
One-click flow:
<ol>
<li><code>POST /auth/send-code</code> returns <code>intent_id</code> and <code>intent_secret</code> when one-click is enabled.</li>
<li>Poll <code>GET|POST /auth/intent-status</code> with <code>intent_id</code> + <code>intent_secret</code>.</li>
<li>After approval, finalize auth via <code>POST /auth/complete-intent</code> with <code>intent_id</code>, <code>intent_secret</code>, and optional <code>issue_token</code> / <code>issue_session</code>.</li>
</ol>
For one-click polling, <code>intent-status</code> supports both:
<ul>
<li><code>GET /auth/intent-status</code> with <code>intent_id</code> + <code>intent_secret</code> query params.</li>
<li><code>POST /auth/intent-status</code> with <code>intent_id</code> + <code>intent_secret</code> in JSON body.</li>
</ul>
Protect site content checks the WordPress cookie session (shortcode login or REST login with <code>issue_session: true</code>). It does not accept Bearer tokens. Protect all REST API content requires a Bearer token and ignores cookie-only sessions.
Download OpenAPI and Postman files from Settings > Reddy Auth > Developer Resources.
<h4>5. Optional: restrict REST callers by browser source</h4>
In Settings > Reddy Auth, Allowed request sources limits plugin REST traffic (<code>/mksddn-reddy-auth/v1/*</code>) to listed <code>Origin</code> or <code>Referer</code> URLs. Leave empty to allow any client (recommended for server-to-server integrations). This is a soft guard for browser apps, not a secret key.
<h4>6. Optional: harden one-click webhook verification</h4>
In Settings > Reddy Auth > One-Click Authorization, set Webhook secret (optional) to match BotMother webhook Secret.
<ul>
<li>With a configured secret, webhook signature verification uses <code>sha256(body + bot_token + "." + webhook_secret)</code>.</li>
<li>With an empty secret, compatibility mode uses <code>sha256(body + bot_token)</code>.</li>
</ul>
<h3>External services</h3>
This plugin connects to the Reddy bot API at <code>https://bot.reddy.team</code> to deliver one-time passwords and optional admin connection test messages.
What the service is used for
<ul>
<li>Deliver OTP codes to a Reddy user during login.</li>
<li>Send an optional admin “bot connection test” message from Settings > Reddy Auth.</li>
</ul>
What data is sent and when
<ul>
<li>OTP send / login: Reddy user ID (<code>userKey</code>) and message text containing the one-time code (and expiry hint). Message text is configurable in Settings > Reddy Auth > Bot Messages (placeholders <code>{code}</code>, <code>{ttl}</code>). Sent when a user requests a code via the login form or REST API.</li>
<li>Bot connection test: Reddy user ID (<code>userKey</code>) and a configurable test message from Settings > Reddy Auth > Bot Messages. Sent only when an administrator runs Bot connection test in Settings > Reddy Auth.</li>
<li>Bot token: Your bot token is included in the API request URL path (configured via <code>MKSDDN_REDDY_BOT_TOKEN</code> in <code>wp-config.php</code> or the development fallback field in settings). It is not sent to WordPress.org.</li>
</ul>
Data is transmitted only when OTP delivery or the connection test is triggered. The plugin does not send site content, post data, or WordPress user passwords to Reddy.
This service is provided by Reddy: terms of use and privacy policy at https://help.reddy.team/pages/user-agreement
No other third-party services are required for core plugin operation.

MksDdn Reddy Auth

Authenticate WordPress users via Reddy OTP flow for monolith and REST API clients.

Ivan

The Google Authenticator plugin for WordPress gives you two-factor authentication using the Google Authenticator app for Android/iPhone/Blackberry.
If you are security aware, you may already have the Google Authenticator app installed on your smartphone, using it for two-factor authentication on Gmail/Dropbox/Lastpass/Amazon etc.
The two-factor authentication requirement can be enabled on a per-user basis. You could enable it for your administrator account, but log in as usual with less privileged accounts.
If You need to maintain your blog using an Android/iPhone app, or any other software using the XMLRPC interface, you can enable the App password feature in this plugin, 
but please note that enabling the App password feature will make your blog less secure.
<h3>Credits</h3>
Thanks to:
<a href="https://profiles.wordpress.org/evinak/" rel="nofollow ugc">Oleksiy</a> for a bugfix in multisite.
<a href="https://github.com/pancek" rel="nofollow ugc">Paweł Nowacki</a> for the Polish translation
<a href="https://github.com/FabioZumbi12" rel="nofollow ugc">Fabio Zumbi</a> for the Portuguese translation
<a href="https://www.guidoschalkx.com/" rel="nofollow ugc">Guido Schalkx</a> for the Dutch translation.
<a href="https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=henrik%40schack%2edk&lc=US&item_name=Google%20Authenticator&item_number=Google%20Authenticator&no_shipping=0&no_note=1&tax=0&bn=PP%2dDonationsBF&charset=UTF%2d8" rel="nofollow ugc">Henrik.Schack</a> for writing/maintaining versions 0.20 through 0.48
<a href="http://tobias.baethge.com/" rel="nofollow ugc">Tobias Bäthge</a> for his code rewrite and German translation.
<a href="http://blog.pcode.nl/" rel="nofollow ugc">Pascal de Bruijn</a> for his “relaxed mode” idea.
<a href="http://technobabbl.es/" rel="nofollow ugc">Daniel Werl</a> for his usability tips.
<a href="http://dd32.id.au/" rel="nofollow ugc">Dion Hulse</a> for his bugfixes.
<a href="https://profiles.wordpress.org/users/aldolat/" rel="nofollow ugc">Aldo Latino</a> for his Italian translation.
<a href="http://www.kaijia.me/" rel="nofollow ugc">Kaijia Feng</a> for his Simplified Chinese translation.
<a href="http://www.buayacorp.com/" rel="nofollow ugc">Alex Concha</a> for his security tips.
<a href="http://jetienne.com/" rel="nofollow ugc">Jerome Etienne</a> for his jquery-qrcode plugin.
<a href="http://orizhial.com/" rel="nofollow ugc">Sébastien Prunier</a> for his Spanish and French translation.

Google Authenticator

Personally I feel 2FA should be a part of WordPress core. But since it isn't, plugins like this one are a must-have to secure your sites.

The configuration interface is clearly layed out and the login page fits in perfectly with the default WP login page styling.

This plugin is light-weight, unobtrusive, free and adds that extra layer of security. Should your admin credentials ever be compromised, 2FA will keep your site secure.

Must-have security plugin

Awesome plugin, which is almost always in first group of plugin I've install on new website. Thank you for create and maintain it.

One on few my first-to-install plugin

Google Authenticator for your WordPress blog.

MksDdn Reddy Auth vs Google Authenticator