What is Remote Procedure Call?
Remote Procedure Call is a technique for building distributed systems, and client/server applications. Basically, it allows a program on one machine to call a subroutine on another machine. RPC is not a transport protocol: rather, it is a method of using existing communications features in a transparent way. Request For Comments (RFC) 1833 (1-3) defines specifics about Remote Procedure Call, and some of its most well know aspects that apply to security specialists, particularly Port Mapper and rpcbind. The remote procedure protocol is documented and discussed in rfc 1790 (specific to Sun rpc) and rfc 1570 has additional information. If you use Unix servers and workstations you may be aware that there are applications that use RPC. There are NFS daemons, lock managers, and license managers. If you are a security manager, you will know that there are many know exploits against a large list of services (and more discovered every day). The first step dishonorably exploit a service is to de
