Rainbow implements the isolation shell implicitly described in the Bitfrost security specification. This means that it isolates activities (and eventually system services) that it is asked to run from one another and the rest of the system.
Rainbow implements this isolation by generating a new uid (and perhaps a new gid) for each program it is asked to run. Running each activity as a separate user means that standard Unix access checks can be used as the primary 'gate' to control the visibility of activity-driven side-effects like reading from or writing to files or devices or signalling other processes.
Design and Implementation
The basic design principles of the present 0.7-series incarnation of rainbow were presented in rainbow.txt. The implementation of rainbow can be found alongside that file in the "rainbow/rainbow" subdirectory of security git repo and in its several forks. Finally, a somewhat dated guided tour of the source code is available.
- P_NETWORK -- Isolation LSM
- cli interface: rainbow-cli
- pristine root patches -- nss-rainbow
- P_DOCUMENT -- Olpcfs
- P_X -- we'll start by trying out XSECURITY (i.e. by making activities untrusted clients) and see where that leaves us. Then on to XACE as per previous discussion