In this section we will describe the Coda security mechanisms as they are currently implemented. The basic reference for this material is the paper "Integrating Security in a Large Distributed System", (M. Satyanarayanan, ACM Transactions on Computer Systems, Vol 7., N. 3. August 1989, Pages 247- 280. ) There are a number of areas where the current system could fairly easily be improved and we will point out these areas.
Basically the security in Coda falls into two parts:
The control of access to files and directories is simpler. Access control is established only after and authenticated connection has been established. It then uses the vice.pcf file in conjunction with the ACL's to determine permissions. The file vol.tk is the shared secret between the volutil clients and the volutil server routines inside srv. This token is used to establish and authenticated connection to the server from a volutil client.
Note: It might make sense to allow a system administrator to get volutil priviliges through a Coda token.
In terms of configuration files on the server, the authentication process uses several:
We will now proceed to describe the two components for security.