Summary
SELinux, by default, uses access controls based on the file representation of communication primitives or the sockets used. On InfiniBand networks, access controls are limited to accessing the InfiniBand port and partitions. For TCP, UDP, and SCTP ports, administrators have some leeway in handling the controls through the semanage command without resorting to SELinux policy updates. Once we go into the realms of network-based communication, more advanced communication control can be accomplished through Linux netfilter support, using SECMARK labeling, and through peer labeling.
In the case of SECMARK labeling, local firewall rules are used to map contexts to packets, which are then governed through SELinux policy. With peer labeling, either the application context itself (labeled IPsec) or its sensitivity level (netfilter/CIPSO) identify the resources the access controls apply. This allows an almost application-to-application network flow control through SELinux policies...