/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
* Copyright (C) 2013 by the Massachusetts Institute of Technology.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Declarations for localauth plugin module implementors.
*
* The localauth pluggable interface currently has only one supported major
* version, which is 1. Major version 1 has a current minor version number of
* 1.
*
* Localauth plugin modules should define a function named
* localauth_<modulename>_initvt, matching the signature:
*
* krb5_error_code
* localauth_modname_initvt(krb5_context context, int maj_ver, int min_ver,
* krb5_plugin_vtable vtable);
*
* The initvt function should:
*
* - Check that the supplied maj_ver number is supported by the module, or
* return KRB5_PLUGIN_VER_NOTSUPP if it is not.
*
* - Cast the vtable pointer as appropriate for maj_ver:
* maj_ver == 1: Cast to krb5_localauth_vtable
*
* - Initialize the methods of the vtable, stopping as appropriate for the
* supplied min_ver. Optional methods may be left uninitialized.
*
* Memory for the vtable is allocated by the caller, not by the module.
*/
#ifndef KRB5_LOCALAUTH_PLUGIN_H
#define KRB5_LOCALAUTH_PLUGIN_H
#include <krb5/krb5.h>
#include <krb5/plugin.h>
/* An abstract type for localauth module data. */
typedef struct krb5_localauth_moddata_st *krb5_localauth_moddata;
/*** Method type declarations ***/
/* Optional: Initialize module data. */
typedef krb5_error_code
(*krb5_localauth_init_fn)(krb5_context context,
krb5_localauth_moddata *data);
/* Optional: Release resources used by module data. */
typedef void
(*krb5_localauth_fini_fn)(krb5_context context, krb5_localauth_moddata data);
/*
* Optional: Determine whether aname is authorized to log in as the local
* account lname. Return 0 if aname is authorized, EPERM if aname is
* authoritatively not authorized, KRB5_PLUGIN_NO_HANDLE if the module cannot
* determine whether aname is authorized, and any other error code for a
* serious failure to process the request. aname will be considered authorized
* if at least one module returns 0 and all other modules return
* KRB5_PLUGIN_NO_HANDLE.
*/
typedef krb5_error_code
(*krb5_localauth_userok_fn)(krb5_context context, krb5_localauth_moddata data,
krb5_const_principal aname, const char *lname);
/*
* Optional (mandatory if an2ln_types is set): Determine the local account name
* corresponding to aname. Return 0 and set *lname_out if a mapping can be
* determined; the contents of *lname_out will later be released with a call to
* the module's free_string method. Return KRB5_LNAME_NOTRANS if no mapping
* can be determined. Return any other error code for a serious failure to
* process the request; this will halt the krb5_aname_to_localname operation.
*
* If the module's an2ln_types field is set, this method will only be invoked
* when a profile "auth_to_local" value references one of the module's types.
* type and residual will be set to the type and residual of the auth_to_local
* value.
*
* If the module's an2ln_types field is not set but the an2ln method is
* implemented, this method will be invoked independently of the profile's
* auth_to_local settings, with type and residual set to NULL. If multiple
* modules are registered with an2ln methods but no an2ln_types field, the
* order of invocation is not defined, but all such modules will be consulted
* before the built-in mechanisms are tried.
*/
typedef krb5_error_code
(*krb5_localauth_an2ln_fn)(krb5_context context, krb5_localauth_moddata data,
const char *type, const char *residual,
krb5_const_principal aname, char **lname_out);
/*
* Optional (mandatory if an2ln is implemented): Release the memory returned by
* an invocation of an2ln.
*/
typedef void
(*krb5_localauth_free_string_fn)(krb5_context context,
krb5_localauth_moddata data, char *str);
/* localauth vtable for major version 1. */
typedef struct krb5_localauth_vtable_st {
const char *name; /* Mandatory: name of module. */
const char **an2ln_types; /* Optional: uppercase auth_to_local types */
krb5_localauth_init_fn init;
krb5_localauth_fini_fn fini;
krb5_localauth_userok_fn userok;
krb5_localauth_an2ln_fn an2ln;
krb5_localauth_free_string_fn free_string;
/* Minor version 1 ends here. */
} *krb5_localauth_vtable;
#endif /* KRB5_LOCALAUTH_PLUGIN_H */