OSF DCE Application Development Guide--Core Components

OSF DCE Application Development Guide—Core Components
The use of authenticated RPC is explained in Chapters 13 and 14. Chapter 14 contains
information about a number of RPC routines that relate directly to security issues, such
as rpc_binding_set_auth_info().
These security chapters, however, contains conceptual information that is useful for
understanding the authentication and authorization protocols that authenticated RPC
routines use; for this information, we recommend that you read Chapters 23 and 24, as
well as this one.
22.3 About the GSSAPI
The GSS provides an alternate way of providing DCE security to distributed applications
that handle network communications by themselves. With GSSAPI, you can include
established applications in DCE and ensure the security and integrity of the applications
and their data. In peer-to-peer communications, the application that establishes the
secure connection is the context initiator or simply initiator. The context initiator is like
a DCE RPC client. The application that accepts the secure connection is the context
acceptor or simply acceptor. The context acceptor is like a DCE RPC server.
The GSS available with DCE includes two sets of routines:
• Standard GSSAPI routines, which are defined in the Internet RFC 1509 ‘‘Generic
Security Service API: C-bindings.’’ These routines have the prefix gss_.
• OSF DCE extensions to the GSSAPI routines. These are additional routines that
enable an application to use DCE security services. These routines have the prefix
gssdce_.
The chapters that follow provide information about how the GSSAPI routines use the
authentication and authorization protocols. Chapter 25 provides information about GSS
credentials, which are used to establish an application’s identity in DCE.
22.4 UNIX System Security and DCE Security
UNIX system security mostly presumes that a computer’s backplane can be trusted
because computing operations are assumed to be local, and because the computer itself
can be physically secured. In a distributed environment, the logical equivalent of the
single system’s backplane is the network itself. Network computing means distributed,
rather than localized, computing operations and, in the case of an open network (which
DCE assumes), little of the network is physically secure. Thus, the nature of distributed
systems poses special security risks, in addition to those posed by nondistributed
systems. Unlike UNIX system security, DCE security is designed specifically to address
those risks.
These considerations notwithstanding, network security is ultimately dependent on the
security features that are local to the individual computers in the network and, what is
more important, the manner in which those features are used and administered. Since
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