[crossfire] Steam Protocol Proposal

[Mark Wedel]

Pippijn van Steenhoven wrote:
> Hi,
> 
> just one thing about SSL streams. I suppose they would be used to transmit
> passwords from the client to the server? Well, if the model was changed and
> the password would not even be transmitted, there would be no need for such
> streams and the entire code would be a lot smaller than it would be with
> SSL streams implemented. Look at how public key authentication works. You
> just send a hash, the server checks whether that hash equals the one in the
> player file and ... and and you get the picture. Public key authentication.

  This depends on what why are trying to protect.

  If the concern is that people are using the same password on crossfire as 
other services, this works - you can't find out a users common password by 
looking at crossfire.  Pretty much any one way method that obfuscates the 
password works (one way hash, etc)

  However, if we are looking to also make the crossfire passwords more secure, 
this doesn't work so well - one just grabs the hash in the player file (core 
file, whatever), and just hack the client to send that hash.

  Now true public key can be used, with the player file storing one key, and the 
other being transmitted.  That helps in the core dump/player analysis (that one 
key doesn't do any good), but doesn't help out much in the case of people 
sniffing - you just sniff what the client is sending to the server, and once 
again, hack your client to send that same byte sequence.

  My personal thought is that starts to over engineer this - I somehow doubt 
there are people out their sniffing the network for crossfire passwords.

  Core dumps/stack traces could be made secure - store the player password in 
something like <playername>.pw and not in the password file itself.  Thus, when 
a player logs in, password compared with that in that file, but once that is 
done, we don't need to keep the password in memory anymore.  It has to be kept 
in memory right now so we know what to write out when saving the player.