man AFS::KAS (3): Class to communicate with the AFS Authentication Server

SYNOPSIS

use AFS::KAS;
use AFS::KTC_PRINCIPAL;
use AFS::KTC_TOKEN;
use AFS::KTC_EKEY;
my $admin = AFS::KTC_PRINCIPAL->new('admin');
my $key = AFS::KTC_EKEY->ReadPassword($admin->name."'s Password:");
my $token = AFS::KTC_TOKEN->GetAdminToken($admin, $key, 300);
my $kas = AFS::KAS->AuthServerConn($token, &AFS::KA_MAINTENANCE_SERVICE);
my $user = AFS::KTC_PRINCIPAL->new('xyz');
my $ukey = AFS::KTC_EKEY->ReadPassword($user->name."'s Password:");
my $ok = $kas->create($user->name, $user->instance, $ukey);
my $flags = 1; # (1 = normal, 4 = admin)
my $expire = 925715000;# epoch time => 03 May 1999 07:03
my $maxassoc = 0;
my $lifetime = 48*60*60; #unit is secs; => 48 hrs
my $pwexpire = 10; #number of days
my $pw_reuse = 2; #pwreuse allowed: [ 2 = no ]
my $nfail = 4; #(nfail - 1) tries are allowed; => 3 tries
my $locktime = 3; #unit is 8.5 min => 3 * (8.5)
my $spare2 = 0;
my $packed = (($pwexpire << 24)|($pw_reuse << 16)|($nfail << 8)|$locktime);
$ok = $kas->setfields($user->name, $user->instance, $flags,
$expire, $lifetime, $maxassoc, $packed);
my $entry = $kas->getentry($user->name, $user->instance);
$packed = $$entry{'misc_auth_bytes'};
$pwexpire = (($packed >> 24) & 0xff);
$is_lockd = (($packed >> 16) & 0xff);
$nfail = (($packed >> 8) & 0xff);
$locktime = (($packed >> 0) & 0xff);
$pw_reuse = $$entry{'passwd_reuse'} - 0x12340000;
$kas->DESTROY; # destroy server connection

DESCRIPTION

This class is used to communicate with the AFS Authentication Server. It verifies user identities and provides the facilities through which participants in transactions prove their identities to one another (mutually authenticate). It maintains the Authentication Database, in which it stores user passwords converted into encryption key form as well as the AFS server encryption key. It has methods to query the information held for any given AFS user and to create, modify, and delete the records in the DB where the above information is held.

Before you can access any DB record you must establish a connection to the Authentication Server. This is done by the constructor methods SingleServerConn and AuthServerConn which return a KAS object. A KAS object is essentially a handle to talk to an Authentication Server in a given cell. Such a KAS object is required before any of the other KAS instance methods can be called.

COMPATIBILITY

This release does NOT support any features and interfaces from version 1.

METHODS

CONSTRUCTOR

$kas = AFS::KAS->AuthServerConn(TOKEN, SERVICE [, CELL]);

Creates a new object of the class AFS::KAS and establishes connections to all the Authentication Servers in a given CELL (default null). An AFS::KAS object is essentially a handle to talk to the Authentication Server. Internally an AFS::KAS object is a pointer to a ubik_client structure, although this may change and the value returned should always be treaded as an opaque handle. A TOKEN may or may not be needed depending on the SERVICE. TOKEN must be an instance of AFS::KTC_TOKEN. Possible values for SERVICE are

   &AFS::KA_MAINTENANCE_SERVICE
   &AFS::KA_AUTHENTICATION_SERVICE
   &AFS::KA_TICKET_GRANTING_SERVICE

It calls the AFS system library function 'ka_AuthServerConn'.

$kas = AFS::KAS->SingleServerConn(HOST, TOKEN, SERVICE [, CELL]);

Creates a new object of the class AFS::KAS and establishes a connection to only one Authentication Server running on HOST in a given CELL (default null). An AFS::KAS object is essentially a handle to talk to the Authentication Server. Internally an AFS::KAS object is a pointer to a ubik_client structure, although this may change and the value returned should always be treaded as an opaque handle. A TOKEN may or may not be needed depending on the SERVICE. TOKEN must be an instance of AFS::KTC_TOKEN. Possible values for SERVICE are

   &AFS::KA_MAINTENANCE_SERVICE

It calls the AFS system library function 'ka_SingleServerConn'.

DESTRUCTOR

$kas->DESTROY;

Destroys the ubik connection to the Authentication Server and frees the ubik connection structure.

INSTANCE METHODS

Nearly all instance methods come in two flavors. The KAM_* methods are essentially the same as the low-level AFS KAS APIs. The other methods are simply just wrappers around the KAM_* methods. These have been introduced in order to offer a more perlish interface :-)

$token = $kas->Authenticate(UNAME, UINST, SERVICE, EKEY, STIME, ETIME [, PWEXP]);

Returns a token for the user entry UNAME.UINST for the specified SERVICE. The desired ticket lifetime is specified by STIME and ETIME (given in 5 minute intervals). This ticket is referred to as the AuthTicket. EKEY contains the encrypted user password and must be an instance of AFS::KTC_EKEY. It assumes that a connection to the AuthServer has already been established. Possible values for SERVICE are

    &AFS::KA_TICKET_GRANTING_SERVICE
    &AFS::KA_MAINTENANCE_SERVICE

It calls the AFS system library function 'ka_Authenticate'

$ok = $kas->ChangePassword(UNAME, UINST, OKEY, NKEY);

Changes the password for the user entry UNAME.UINST in the Authentication Database to NKEY. OKEY and NKEY must be instances of AFS::KTC_EKEY. OEKY is never used, so you can put in any key (randomkey). It calls the AFS system library function 'ka_ChangePassword'.

$ok = $kas->create(UNAME, UINST, NKEY);

$ok = $kas->KAM_CreateUser(UNAME, UINST, NKEY);

Adds the user entry UNAME.UINST to the Authentication Database and sets its password key to NKEY. NKEY must be an instance of AFS::KTC_EKEY. This call requires a connection encrypted with an AdminTicket. It calls the AFS system library function 'KAM_CreateUser'.

$entry = $kas->debug;

$entry = $kas->KAM_Debug(VERSION);

Returns information about the Authentication Database, the key cache, and the state of the AuthServer. The return value is a reference to a hash table containing the values from the C structure "ka_debugInfo". Possible values for VERSION are

   &AFS::KAMAJORVERSION

It calls the AFS system library function'KAM_Debug'.

$ok = $kas->delete(UNAME, UINST);

$ok = $kas->KAM_DeleteUser(UNAME, UINST);

Removes the user entry UNAME.UINST from the Authentication Database. It requires a connection encrypted with an AdminTicket. It calls the AFS system library function 'KAM_DeleteUser'.

$entry = $kas->getentry(UNAME, UINST);

$entry = $kas->KAM_Getentry(UNAME, UINST);

Returns information from the Authentication Database entry for the user entry UNAME.UINST. The return value is a reference to a hash table containing the values from the C structure "kaentryinfo". The hash table has the following keys

    change_password_time    flags                  keyCheckSum
    key_version             max_ticket_lifetime    minor_version
    misc_auth_bytes         modification_time      modification_user
    user_expiration

It calls the AFS system library function 'KAM_GetEntry'.

($num_admins, $kasstats, $kadstats) = $kas->getstats;

($num_admins, $kasstats, $kadstats) = $kas->KAM_GetStats(VERSION);

Returns statistics about the AuthServer and its database. If VERSION does not match that used by the server, the call returns an error code. The return values are references to the hash tables containing the values from the C structures "kasstats" and "kadstats". This call requires a connection encrypted with an AdminTicket. Possible values for VERSION are

   &AFS::KAMAJORVERSION

It calls the AFS system library function 'KAM_Getstats'.

$token = $kas->GetToken(SNAME, SINST, STIME, ETIME, AUTH_TOKEN [, AUTH_CELL]);

Return a token for the specified service SNAME.SINST. The desired ticket lifetime is specified by STIME and ETIME (given in 5 minute intervals). AUTH_TOKEN must be a ticket for the ticketgranting service (an instance of AFS::KTC_TOKEN) in the cell AUTH_CELL (default null). It assumes that a connection to the AuthServer has already been established. It calls the AFS system library function 'ka_GetToken'.

($name, $inst) = $kas->listentry(PREV, INDX, COUNT);

($name, $inst) = $kas->KAM_ListEntry(PREV, INDX, COUNT);

Returns the name and instance of an entry in the database. It provides a way to step through all the entries in the database. The first call should be made with previous index PREV set to zero. The method updates COUNT, which is an estimate of the number of entries remaining to be returned, and INDX, which should be passed in as previous index on the next call. A negative COUNT or a nonzero return code indicates that an error occurred. A zero INDX means there were no more entries. A zero COUNT means the last entry has been returned. This call requires a connection encrypted with an AdminTicket. It calls the AFS system library function 'KAM_ListEntry'.

$rkey = $kas->randomkey;

$rkey = $kas->KAM_GetRandomKey;

Returns a random DES key (an instance of AFS::KTC_EKEY) and is preferred over a calling routine just inventing a key. It calls the AFS system library function 'KAM_GetRandomKey'.

$ok = $kas->setpassword(UNAME, UINST, KVNO, NKEY);

$ok = $kas->KAM_SetPassword(UNAME, UINST, KVNO, NKEY);

Sets the key NKEY and key version number KVNO of the user entry UNAME.UINST to the given values. NKEY must be an instance of AFS::KTC_EKEY. This call requires a connection encrypted with an AdminTicket. It calls the AFS system library function 'KAM_SetPassword'.

$ok = $kas->setfields(UNAME, UINST, FLAGS, EXPIRE, LIFETIME, MAXASSOC, PACKED);

$ok = $kas->KAM_SetFields(UNAME, UINST, FLAGS, EXPIRE, LIFETIME, MAXASSOC, PACKED);

This function alters the miscellaneous parameters associated with the user entry UNAME.UINST. The FLAGS argument can be set to the following values

   &AFS::KAFNORMAL    regular user
   &AFS::KAFADMIN     an administrator
   &AFS::KAFNOTGS     not allow principal to get or use TGT
   &AFS::KAFNOSEAL    not allow principal as server in GetTicket
   &AFS::KAFNOCPW     not allow principal to change its own key
   &AFS::KAFNEWASSOC  allow user to create associates

EXPIRE is the epoch time after which attempts to authenticate as this user will fail. The LIFETIME can be set to limit the lifetime of an authentication ticket created for a user (unit is secs). MAXASSOC defaults to -1. PACKED is an array of four bytes. It contains

  PACKED[0]: password lifetime; range must be [0..254] days; 0 = infinity
  PACKED[1]: password reuse; [1 = yes], [2 = no], [0 = not changed]
  PACKED[2]: numb of failed logins; (fail - 1) tries are allowed; 0 = infinity
  PACKED[3]: lock time, must be set in units of 8.5 minutes; 0 = infinity

This call requires a connection encrypted with an AdminTicket. It calls the AFS system library function 'KAM_SetFields'.

CURRENT AUTHOR

Norbert E. Gruener <[email protected]>.

AUTHOR EMERITUS

Roland Schemers <[email protected]>.

COPYRIGHT AND DISCLAIMER

 X 2001-2008 Norbert E. Gruener <[email protected]>.
 All rights reserved.
 X 1994 Board of Trustees, Leland Stanford Jr. University.
 All rights reserved.
 Most of the explanations in this document are taken from the original
 AFS documentation.
 AFS-3 Programmer's Reference:
 Authentication Server Interface
 Edward R. Zayas
 X 1991 Transarc Corporation.
 All rights reserved.
 IBM AFS Administration Reference
 X IBM Corporation 2000.
 All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

The original module is covered by the following copyright:: Copyright (c) 1994 Board of Trustees, Leland Stanford Jr. University
Redistribution and use in source and binary forms are permitted provided that the above copyright notice and this paragraph are duplicated in all such forms and that any documentation, advertising materials, and other materials related to such distribution and use acknowledge that the software was developed by Stanford University. The name of the University may not be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

DOCUMENT VERSION

Revision $Rev: 899 $