Servers need to be able to operate on a client's principal name. Such a name is stored by the server as a rpc_gss_principal_t structure, an opaque byte string which can be used either directly in access control lists or as database indices which can be used to look up a UNIX credential. A server may, for example, need to compare a principal name it has received with the principal name of a known entity, and to do that, it must be able to generate rpc_gss_principal_t structures from known entities.

rpc_gss_get_principal_name() takes as input a security mechanism, a pointer to a rpc_gss_principal_t structure, and several parameters which uniquely identify an entity on a network: a user or service name, a node name, and a domain name. From these parameters it constructs a unique, mechanism-dependent principal name of the rpc_gss_principal_t structure type.

How many of the identifying parameters (name , node, and domain) are necessary to specify depends on the mechanism being used. For example, Kerberos V5 requires only a user name but can accept a node and domain name. An application can choose to set unneeded parameters to NULL.

Information on RPCSEC_GSS data types for parameters may be found on the rpcsec_gss(3NSL) man page.

principal

An opaque, mechanism-dependent structure representing the client's principal name.

mech

An ASCII string representing the security mechanism in use. Valid strings may be found in the /etc/gss/mech file, or by using rpc_gss_get_mechanisms().

name

A UNIX login name (for example, 'gwashington') or service name, such as 'nfs'.

node

A node in a domain; typically, this would be a machine name (for example, 'valleyforge').

domain

A security domain; for example, a DNS, NIS, or NIS+ domain name ('eng.company.com').

rpc_gss_get_principal_name() returns TRUE if it is successful; otherwise, use rpc_gss_get_error() to get the error associated with the failure.

/etc/gss/mech

File containing valid security mechanisms

See attributes(5) for descriptions of the following attributes:

free(3C), rpc(3NSL), rpc_gss_get_mechanisms(3NSL), rpc_gss_set_svc_name(3NSL), rpcsec_gss(3NSL), mech(4), attributes(5)

ONC+ Developer's Guide

Linn, J. RFC 2078, Generic Security Service Application Program Interface, Version 2. Network Working Group. January 1997.

Principal names may be freed up by a call to free(3C). A principal name need only be freed in those instances where it was constructed by the application. (Values returned by other routines point to structures already existing in a context, and need not be freed.)