rpc_gss_set_callback(3N)rpc_gss_set_callback(3N)NAMErpc_gss_set_callback() - specify callback for context
SYNOPSISDESCRIPTION
A server may want to specify a callback routine so that it knows when a
context gets first used. This user-defined callback may be specified
through the routine. The callback routine is invoked the first time a
context is used for data exchanges, after the context is established
for the specified program and version.
The user-defined callback routine should take the following form:
PARAMETERS
takes one argument: a pointer to a structure. This structure contains
the RPC program and version number as well as a pointer to a user-
defined routine. For a description of and other data types, see the
rpcsec_gss(3N) manpage.
The user-defined routine itself takes the following arguments:
req Pointer to the received service request. svc_req is an RPC
structure containing information on the context of an RPC
invocation, such as program, version, and transport infor‐
mation.
deleg Delegated credentials, if any. (See WARNING, below.)
gss_context GSS context (allows the server to do GSS operations on the
context to test for acceptance criteria). (See below.)
lock This parameter is used to enforce a particular QOP and ser‐
vice for a session. This parameter points to a structure.
When the call-back is invoked, the field is set to thus
locking the context. A locked context will reject all
requests having different values for QOP or service than
those specified by the raw_cred field of the structure.
cookie A four-byte quantity that an application may use in any
manner because RPC does not interpret it. For example, the
cookie could be a pointer or index to a structure that rep‐
resents a context initiator. The cookie is returned, along
with the caller's credentials, with each invocation of
MULTITHREAD USAGE
Thread Safe: Yes
Cancel Safe: Yes
Fork Safe: No
Async-cancel Safe: No
Async-signal Safe: No
These functions can be called safely in a multithreaded environment.
They may be cancellation points in that they call functions that are
cancel points.
In a multithreaded environment, these functions are not safe to be
called by a child process after and before These functions should not
be called by a multithreaded application that supports asynchronous
cancellation or asynchronous signals.
RETURN VALUE
returns if the use of the context is accepted; otherwise.
WARNING
If a server does not specify a callback, all incoming contexts will be
accepted.
Because the is not currently exposed, the deleg and gss_context argu‐
ments are mentioned for informational purposes only, and the user-
defined callback function may choose to do nothing with them.
SEE ALSOrpc(3N), rpc_gss_getcred(3N), rpcsec_gss(3N).
Network Working Group RFC 2078
rpc_gss_set_callback(3N)