Steamworks Documentation
ISteamUserAuth Interface
Used to access information about users.

For more info on how to use the Steamworks Web API please see the Web API Overview.

AuthenticateUser

POST https://partner.steam-api.com/ISteamUserAuth/AuthenticateUser/v1/
NameTypeRequiredDescription
steamiduint64Should be the users steamid, unencrypted.
sessionkeyrawbinaryShould be a 32 byte random blob of data, which is then encrypted with RSA using the Steam system's public key. Randomness is important here for security.
encrypted_loginkeyrawbinaryShould be the users hashed loginkey, AES encrypted with the sessionkey.

AuthenticateUserTicket

GET https://partner.steam-api.com/ISteamUserAuth/AuthenticateUserTicket/v1/
NameTypeRequiredDescription
keystringSteamworks Web API publisher authentication key
appiduint32appid of game
ticketstringConvert the binary ticket data from GetAuthTicketForWebApi into a hexadecimal string and pass that string in as this parameter.
identitystringIdentifying string passed as a parameter to GetAuthTicketForWebApi when the ticket was created, used to identify the entity calling this webapi. If this identity string is passed, only tickets created with that parameter will successfully authenticate.

Returns: The user's 64-bit SteamID if the user's ticket is valid

NOTE: This call requires a publisher API key to use this method. As such this API MUST be called from a secure server, and can never be used directly by clients!

AuthenticateUserTIcket is also available for games servers via the https://api.steampowered.com/ domain using a Web API user authentication key. These requests are rate limited.