Tips for security
KeyAuth is an authentication API, not a client-side obfuscation service. The developer (you) are responsible for protecting your code. This is a standard in the industry in other authentication services.
There's no point in doing below steps if you're sending request from a server. As servers won't need this protection as the user won't be able to modify network traffic between the server and KeyAuth API
GUID Setup
You're going to want to include a random GUID in the enckey paramater with the initialization request to the 1.2 API endpoint. Make sure the length of the GUID is 36 characters or less. You will send this GUID in the enckey parameter only on init, none of the other requests.
And then store this GUID along with your application secret for later checking. Like this [GUID]-[secret]
So if my GUID I passed in the enckey parameter was 4a59f8ca-b304-47 and my app secret is 76489f2ba92ddf9132e28d56870004a62d30ec5b40eaf2071ae48036e7144b5f I want to store the string 4a59f8ca-b304-47-76489f2ba92ddf9132e28d56870004a62d30ec5b40eaf2071ae48036e7144b5f for later use
For Initialization Response
For initialization request responses, there's a signature header which is a SHA256 HMAC of the JSON response encoded with the application secret.
So the header is signature: 8d0a11b00f44bee4e563117db28533943f5170854f5f65e69470c59bffb7d0d5 and the JSON response is:
{"success":true,"message":"Initialized","sessionid":"b8Q1f62SdW","appinfo":{"numUsers":"6","numOnlineUsers":"120","numKeys":"1533","version":"1.0","customerPanelLink":"https:\/\/localhost\/panel\/wnelson03\/test\/"}}
Encoding the above JSON with my application secret 76489f2ba92ddf9132e28d56870004a62d30ec5b40eaf2071ae48036e7144b5f on the website HMAC SHA256 ONLINE, I get the output 8d0a11b00f44bee4e563117db28533943f5170854f5f65e69470c59bffb7d0d5. In my application, I compare these and abort the program if they don't match.
For All Other Responses
For all other requests, you're going to need that string you saved earlier, [GUID]-[secret]
My string is `4a59f8ca-b304-47-76489f2ba92ddf9132e28d56870004a62d30ec5b40eaf2071ae48036e7144b5f and the JSON response is:
{"success":true,"message":"Logged in!","info":{"username":"3Y8FC2-MRHKUO-U9RH8I-GNHD2U-THK4X8-PW584D","subscriptions":[{"subscription":"default","key":"3Y8FC2-MRHKUO-U9RH8I-GNHD2U-THK4X8-PW584D","expiry":"1659657607"},{"subscription":"default","key":null,"expiry":"1659749662"}],"ip":"::1","hwid":null,"createdate":"1659225608","lastlogin":"1659363059"}}
and the header I received was signature: e2993347290077c90011694bf887975117bff08897106f9c501d75c48102f721
Encoding the JSON response I received with the string I saved before I made the init request, 4a59f8ca-b304-47-76489f2ba92ddf9132e28d56870004a62d30ec5b40eaf2071ae48036e7144b5f on the website HMAC SHA256 ONLINE I get the same result as the signature e2993347290077c90011694bf887975117bff08897106f9c501d75c48102f721.