gss_acquire_cred(3)

NAME
gss_acquire_cred - API function

SYNOPSIS
#include <gss.h>

OM_uint32 gss_acquire_cred(OM_uint32 * minor_status, const gss_name_t desired_name, OM_uint32 time_req, const gss_OID_set desired_mechs, gss_cred_usage_t cred_usage, gss_cred_id_t * output_cred_handle, gss_OID_set * actual_mechs, OM_uint32 * time_rec);

ARGUMENTS

OM_uint32 * minor_status
    (integer, modify) Mechanism specific status code.

const gss_name_t desired_name
    (gss_name_t, read) Name of principal whose
      credential should be acquired.

OM_uint32 time_req
    (Integer, read, optional) Number of seconds that
      credentials should remain valid. Specify GSS_C_INDEFINITE to
      request that the credentials have the maximum permitted lifetime.

const gss_OID_set desired_mechs
    (Set of Object IDs, read, optional) Set of
      underlying security mechanisms that may be used.
      GSS_C_NO_OID_SET may be used to obtain an implementation-specific
      default.

gss_cred_usage_t cred_usage
    (gss_cred_usage_t, read) GSS_C_BOTH - Credentials may
      be used either to initiate or accept security contexts.
      GSS_C_INITIATE - Credentials will only be used to initiate
      security contexts. GSS_C_ACCEPT - Credentials will only be used
      to accept security contexts.

gss_cred_id_t * output_cred_handle
    (gss_cred_id_t, modify) The returned
      credential handle. Resources associated with this credential
      handle 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 set of
      mechanisms for which the credential is valid. Storage associated
      with the returned OID-set must be released by the application
      after use with a call to gss_release_oid_set(). Specify NULL if
      not required.

OM_uint32 * time_rec
    (Integer, modify, optional) Actual number of seconds for
      which the returned credentials will remain valid. If the
      implementation does not support expiration of credentials, the
      value GSS_C_INDEFINITE will be returned. Specify NULL if not
      required.

DESCRIPTION
Allows an application to acquire a handle for a pre-existing credential by name. GSS-API implementations must impose a local access-control policy on callers of this routine to prevent unauthorized callers from acquiring credentials 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 credentials rather than merely acquiring a handle to existing credentials. 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 for a credential handle 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).

Mechanisms should honor the desired_mechs parameter, and return a credential that is suitable to use only with the requested mechanisms. An exception to this is the case where one underlying credential element can be shared by multiple mechanisms; in this case it is permissible for an implementation to indicate all mechanisms with which the credential element may be used. If desired_mechs is an empty set, behavior is undefined.

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_acquire_cred must return valid credential data, and may therefore incur the overhead of a deferred credential acquisition.

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_CREDENTIALS_EXPIRED`: The credentials could not be acquired 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 © 2003-2013 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.