NAME
gss_add_cred - API function
SYNOPSIS
#include <gss.h>
OM_uint32 gss_add_cred(OM_uint32 * minor_status, const gss_cred_id_t
input_cred_handle, const gss_name_t desired_name, const gss_OID
desired_mech, gss_cred_usage_t cred_usage, OM_uint32
initiator_time_req, OM_uint32 acceptor_time_req, gss_cred_id_t *
output_cred_handle, gss_OID_set * actual_mechs, OM_uint32 *
initiator_time_rec, OM_uint32 * acceptor_time_rec);
ARGUMENTS
OM_uint32 * minor_status
(integer, modify) Mechanism specific status code.
const gss_cred_id_t input_cred_handle
(gss_cred_id_t, read, optional) The credential
to which a credential-element will be added. If
GSS_C_NO_CREDENTIAL is specified, the routine will
compose the
new credential based on default behavior (see text).
Note that, while the credential-handle is not modified by
gss_add_cred(), the underlying credential will be
modified if
output_credential_handle is NULL.
const gss_name_t desired_name
(gss_name_t, read.) Name of principal whose
credential should be acquired.
const gss_OID desired_mech
(Object ID, read) Underlying security mechanism with
which the credential may be used.
gss_cred_usage_t cred_usage
(gss_cred_usage_t, read) GSS_C_BOTH - Credential may
be used either to initiate or accept security contexts.
GSS_C_INITIATE - Credential will only be used to initiate
security contexts. GSS_C_ACCEPT - Credential will only
be used
to accept security contexts.
OM_uint32 initiator_time_req
(Integer, read, optional) number of seconds
that the credential should remain valid for initiating
security
contexts. This argument is ignored if the composed
credentials
are of type GSS_C_ACCEPT. Specify GSS_C_INDEFINITE to
request
that the credentials have the maximum permitted initiator
lifetime.
OM_uint32 acceptor_time_req
(Integer, read, optional) number of seconds
that the credential should remain valid for accepting
security
contexts. This argument is ignored if the composed
credentials
are of type GSS_C_INITIATE. Specify GSS_C_INDEFINITE to
request
that the credentials have the maximum permitted initiator
lifetime.
gss_cred_id_t * output_cred_handle
(gss_cred_id_t, modify, optional) The returned
credential handle, containing the new credential-element
and all
the credential-elements from input_cred_handle. If a
valid
pointer to a gss_cred_id_t is supplied for this
parameter,
gss_add_cred creates a new credential handle containing
all
credential-elements from the input_cred_handle and the
newly
acquired credential-element; if NULL is specified for
this
parameter, the newly acquired credential-element will be
added to
the credential identified by input_cred_handle. The
resources
associated with any credential handle returned via this
parameter
must be released by the application after use with a call
to
gss_release_cred().
gss_OID_set * actual_mechs
(Set of Object IDs, modify, optional) The complete
set of mechanisms for which the new credential is valid.
Storage
for the returned OID-set must be freed by the application
after
use with a call to gss_release_oid_set(). Specify NULL if
not
required.
OM_uint32 * initiator_time_rec
(Integer, modify, optional) Actual number of
seconds for which the returned credentials will remain
valid for
initiating contexts using the specified mechanism. If
the
implementation or mechanism does not support expiration
of
credentials, the value GSS_C_INDEFINITE will be returned.
Specify
NULL if not required
OM_uint32 * acceptor_time_rec
(Integer, modify, optional) Actual number of
seconds for which the returned credentials will remain
valid for
accepting security contexts using the specified
mechanism. If
the implementation or mechanism does not support
expiration of
credentials, the value GSS_C_INDEFINITE will be returned.
Specify
NULL if not required
DESCRIPTION
Adds a credential-element to a credential. The credential-element is
identified by the name of the principal to which it refers. GSS-API
implementations must impose a local access-control policy on callers of
this routine to prevent unauthorized callers from acquiring
credential-elements to which they are not entitled. This routine is not
intended to provide a "login to the network" function, as such a
function would involve the creation of new mechanism-specific
authentication data, rather than merely acquiring a GSS-API handle to
existing data. Such functions, if required, should be defined in
implementation-specific extensions to the API.
If desired_name is GSS_C_NO_NAME, the call is interpreted as a request
to add a credential element that will invoke default behavior when
passed to gss_init_sec_context() (if cred_usage is GSS_C_INITIATE or
GSS_C_BOTH) or gss_accept_sec_context() (if cred_usage is GSS_C_ACCEPT
or GSS_C_BOTH).
This routine is expected to be used primarily by context acceptors,
since implementations are likely to provide mechanism-specific ways of
obtaining GSS-API initiator credentials from the system login process.
Some implementations may therefore not support the acquisition of
GSS_C_INITIATE or GSS_C_BOTH credentials via gss_acquire_cred for any
name other than GSS_C_NO_NAME, or a name produced by applying either
gss_inquire_cred to a valid credential, or gss_inquire_context to an
active context.
If credential acquisition is time-consuming for a mechanism, the
mechanism may choose to delay the actual acquisition until the
credential is required (e.g. by gss_init_sec_context or
gss_accept_sec_context). Such mechanism-specific implementation
decisions should be invisible to the calling application; thus a call
of gss_inquire_cred immediately following the call of gss_add_cred must
return valid credential data, and may therefore incur the overhead of a
deferred credential acquisition.
This routine can be used to either compose a new credential containing
all credential-elements of the original in addition to the
newly-acquire credential-element, or to add the new credential- element
to an existing credential. If NULL is specified for the
output_cred_handle parameter argument, the new credential-element will
be added to the credential identified by input_cred_handle; if a valid
pointer is specified for the output_cred_handle parameter, a new
credential handle will be created.
If GSS_C_NO_CREDENTIAL is specified as the input_cred_handle,
gss_add_cred will compose a credential (and set the output_cred_handle
parameter accordingly) based on default behavior. That is, the call
will have the same effect as if the application had first made a call
to gss_acquire_cred(), specifying the same usage and passing
GSS_C_NO_NAME as the desired_name parameter to obtain an explicit
credential handle embodying default behavior, passed this credential
handle to gss_add_cred(), and finally called gss_release_cred() on the
first credential handle.
If GSS_C_NO_CREDENTIAL is specified as the input_cred_handle parameter,
a non-NULL output_cred_handle must be supplied.
RETURN VALUE
‘GSS_S_COMPLETE‘: Successful completion.
‘GSS_S_BAD_MECH‘: Unavailable mechanism requested.
‘GSS_S_BAD_NAMETYPE‘: Type contained within desired_name parameter is
not supported.
‘GSS_S_BAD_NAME‘: Value supplied for desired_name parameter is
ill-formed.
‘GSS_S_DUPLICATE_ELEMENT‘: The credential already contains an element
for the requested mechanism with overlapping usage and validity period.
‘GSS_S_CREDENTIALS_EXPIRED‘: The required credentials could not be
added because they have expired.
‘GSS_S_NO_CRED‘: No credentials were found for the specified name.
REPORTING BUGS
Report bugs to <bug-gss@gnu.org>. GNU Generic Security Service home
page: http://www.gnu.org/software/gss/ General help using GNU software:
http://www.gnu.org/gethelp/
COPYRIGHT
Copyright © 2003-2010 Simon Josefsson.
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.
SEE ALSO
The full documentation for gss is maintained as a Texinfo manual. If
the info and gss programs are properly installed at your site, the
command
info gss
should give you access to the complete manual.