How to add content verification using hmac in PHP

Posted 25 CommentsPosted in PHP
Many times a requirement arises where we are supposed to expose an API for intended users, who can use these API endpoints to GET/POST data on our servers. But how do we verify that only the intended users are using these API's and not any hacker or attacker. In this blog post, I will show you the most elegant way of adding content verification using hash_hmac (Hash-based Message Authentication Code) in PHP. This will allow us to restrict possible misuse of our API by simply issuing an API key for intended users. Here are the steps for adding content verification...