Add piracy checking

Description

It is believed that tML needs Steam to run, but recently I found that a modified steam_api.dll can be used to bypass the Steam check. Many players here do not want to pay for the game, so they use a pirate version of Terraria, and also tML if replacing the executable. Thus, I think a check on steam_api.dll should be performed.

Versions

All versions.

Additional Information

I suggest to perform a SHA1 or any other Hash check on the library before running SocialAPI to check the integrity of official version of tML including any other libraries it uses.

The SHA1 hash of vanilla steam_api.dll is 4ee43374520904fa6d80c12c273d67eb7b5c984e. I wrote my own solution as follows:

byte[] b = new byte[] { 0x4e, 0xe4, 0x33, 0x74, 0x52, 0x09, 0x04, 0xfa, 0x6d, 0x80, 0xc1, 0x2c, 0x27, 0x3d, 0x67, 0xeb, 0x7b, 0x5c, 0x98, 0x4e };
var data = File.ReadAllBytes("steam_api.dll");
var hash = SHA1.Create().ComputeHash(data);
if (hash.SequenceEqual(b)) {...}    // using System.Linq

Also, the pirate version of steam_api.dll can be downloaded here: [modified_steam_api.zip]

[Chicken-Bones]

See, you’re missing the part where anyone can modify and build tModLoader to remove the check.

[Ristovski]

You are talking about adding another check to Terraria to battle piracy and then yourself provide a “modified” steam_api.dll.

Also, how would this work on Linux/Mac? They use native versions of steam_api.so and not the Windows dll.

If you were to implement the check with a basic sha1sum “integrity” check I can assure you that can be cracked with a single sed command under Linux by directly replacing the sha1sum with the one from the “modified” steam_api.{so,dll}.

Which means you would have to actually put effort into creating a non-trivial DRM.

Is tModLoader supposed to be a DRM? No.