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KLOG.KRB5(1)		     AFS Command Reference		  KLOG.KRB5(1)

NAME
       klog.krb5 - Authenticates to Kerberos and obtains a token

SYNOPSIS
       klog.krb5 [-x] [-principal <user	name>]
	   [-password <user's password>] [-cell	<cell name>]
	   [-k <realm>]	[-pipe]	[-silent]
	   [-lifetime <ticket lifetime in hh[:mm[:ss]]>]
	   [-setpag] [-tmp] [-noprdb] [-unwrap]	[-help]

       klog.krb5 [-x] [-pr <user name>]
	   [-pa	<user's	password>]
	   [-c <cell name>]
	   [-k <realm>]	[-pi] [-si]
	   [-l <ticket lifetime	in hh[:mm[:ss]]>]
	   [-se] [-t] [-n] [-u]	[-h]

DESCRIPTION
       The klog.krb5 command obtains a Kerberos	v5 ticket from a Kerberos KDC
       and, from the ticket, an	AFS token and then stores it in	the Cache
       Manager.	 The Cache Manager keeps the token in kernel memory and	uses
       it when obtaining authenticated access to the AFS filespace.  This
       command does not	affect the issuer's identity (UNIX UID)	on the local
       file system.

       By default, the command interpreter obtains a token for the AFS user
       name that matches the issuer's local user name.	To specify an
       alternate user, include the -principal argument.	 The user named	by the
       -principal argument does	not have to appear in the local	password file
       (the /etc/passwd	file or	equivalent).

       By default, the command interpreter obtains a token for the local cell,
       as defined by the AFSCELL environment variable set in the command shell
       or by the /usr/local/etc/openafs/ThisCell file on the local machine.
       To specify an alternate cell, include the -cell argument.  A user can
       have tokens in multiple cells simultaneously, but only one token	per
       cell per	connection to the client machine.  If the user's credential
       structure already contains a token for the requested cell, the token
       resulting from this command replaces it.

       By default, the command interpreter obtains a Kerberos ticket for the
       local realm.  To	specify	a different Kerberos realm, include the	-k
       argument.  The Kerberos realm name need not match the AFS cell name.
       klog.krb5 will request a	ticket for the principal "afs/cell" where cell
       is the cell name	for which the user is requesting tokens, falling back
       on the principal	"afs" if that principal	does not work.

       The lifetime of the token resulting from	this command is	the smallest
       of the following:

       o   The lifetime	specified by the issuer	with the -lifetime argument if
	   that	argument was given.

       o   The maximum ticket lifetime recorded	for the	"afs/cell" principal
	   in thet Kerberos database.

       o   The maximum ticket lifetime recorded	in the specified user's
	   Kerberos database entry.

CAUTIONS
       By default, this	command	does not create	a new process authentication
       group (PAG); see	the description	of the pagsh command to	learn about
       PAGs.  If a cell	does not use an	AFS-modified login utility, users must
       include -setpag option to this command, or issue	the pagsh command
       before this one,	to have	their tokens stored in a credential structure
       that is identified by PAG rather	than by	local UID.  Users should be
       aware that -setpag will not work	on some	systems, most notably recent
       Linux systems, and using	pagsh is preferrable and more reliable.

       When a credential structure is identified by local UID, the potential
       security	exposure is that the local superuser "root" can	use the	UNIX
       su command to assume any	other identity and automatically inherit the
       tokens associated with that UID.	 Identifying the credential structure
       by PAG makes it more difficult (but not impossible) for the local
       superuser to obtain tokens of other users.

       If the -password	argument is used, the specified	password cannot	begin
       with a hyphen, because it is interpreted	as another option name.	 Use
       of the -password	argument is not	recommended in any case.

       By default, it is possible to issue this	command	on a properly
       configured NFS client machine that is accessing AFS via the NFS/AFS
       Translator, assuming that the NFS client	machine	is a supported system
       type. However, if the translator	machine's administrator	has enabled
       UID checking by including the -uidcheck on argument to the fs exportafs
       command,	the command fails with an error	message	similar	to the
       following:

	  Warning: Remote pioctl to <translator_machine> has failed (err=8). . .
	  Unable to authenticate to AFS	because	a pioctl failed.

       Enabling	UID checking means that	the credential structure in which
       tokens are stored on the	translator machine must	be identified by a UID
       that matches the	local UID of the process that is placing the tokens in
       the credential structure.  After	the klog.krb5 command interpreter
       obtains the token on the	NFS client, it passes it to the	remote
       executor	daemon on the translator machine, which	makes the system call
       that stores the token in	a credential structure on the translator
       machine.	 The remote executor generally runs as the local superuser
       "root", so in most cases	its local UID (normally	zero) does not match
       the local UID of	the user who issued the	klog.krb5 command on the NFS
       client machine.

       Issuing the klog.krb5 command on	an NFS client machine creates a
       security	exposure: the command interpreter passes the token across the
       network to the remote executor daemon in	clear text mode.

OPTIONS
       -x  Appears only	for backwards compatibility.  Its former function is
	   now the default behavior of this command.

       -principal <user	name>
	   Specifies the user name to authenticate.  If	this argument is
	   omitted, the	default	value is the local user	name.

       -password <user's password>
	   Specifies the issuer's password (or that of the alternate user
	   identified by the -principal	argument).  Omit this argument to have
	   the command interpreter prompt for the password, in which case it
	   does	not echo visibly in the	command	shell.

       -cell <cell name>
	   Specifies the cell for which	to obtain a token.  During a single
	   login session on a given machine, a user can	be authenticated in
	   multiple cells simultaneously, but can have only one	token at a
	   time	for each of them (that is, can only authenticate under one
	   identity per	cell per session on a machine).	 It is acceptable to
	   abbreviate the cell name to the shortest form that distinguishes it
	   from	the other cells	listed in the
	   /usr/local/etc/openafs/CellServDB file on the client	machine	on
	   which the command is	issued.

	   If this argument is omitted,	the command is executed	in the local
	   cell, as defined

	   o   First, by the value of the environment variable AFSCELL.

	   o   Second, in the /usr/local/etc/openafs/ThisCell file on the
	       client machine on which the command is issued.

       -k <realm>
	   Obtain tickets and tokens from the <realm> Kerberos realm.  If this
	   option is not given,	klog.krb5 defaults to using the	default	local
	   realm.  The Kerberos	realm name need	not match the AFS cell name.

       -pipe
	   Suppresses all output to the	standard output	stream,	including
	   prompts and error messages. The klog.krb5 command interpreter
	   expects to receive the password from	the standard input stream. Do
	   not use this	argument; it is	designed for use by application
	   programs rather than	human users.

       -silent
	   Suppresses some of the trace	messages that the klog.krb5 command
	   produces on the standard output stream by default.  It still
	   reports on major problems encountered.

       -lifetime <ticket lifetime
	   Requests a specific lifetime	for the	token.	Provide	a number of
	   hours and optionally	minutes	and seconds in the format
	   hh[:mm[:ss]].

       -setpag
	   Creates a process authentication group (PAG)	prior to requesting
	   authentication. The token is	associated with	the newly created PAG.

       -tmp
	   Creates a Kerberos-style ticket file	rather than only obtaining
	   tokens.  The	ticket file will be stored in the default Kerberos
	   ticket cache	location, which	is usually in the /tmp directory of
	   the local machine (but depends on the Kerberos implementation
	   used).

       -noprdb
	   By default, klog.krb5 looks up the user's AFS ID in the Protection
	   Server and associates the token with	that AFS ID.  This is helpful
	   when	looking	at the output of commands like tokens but is not
	   required.  If this option is	given, this behavior is	suppressed and
	   klog.krb5 will store	the token under	a generic name.	 You may wish
	   this	if, for	example, you have problems contacting the Protection
	   Server for an AFS cell for some reason.

       -unwrap
	   Normally, klog.krb5 uses the	Kerberos service ticket	for the	AFS
	   principal as	the AFS	token.	If this	option is given, klog.krb5
	   creates a different,	simplified AFS token form based	on the service
	   ticket (the so-called "rxkad	2b" token).  Normally, this is not
	   necessary.  However,	if you are using older OpenAFS software	that
	   cannot handle large ticket sizes in conjunction with	Active
	   Directory as	the Kerberos server, using -unwrap can shrink the AFS
	   token size so that older software can handle	it more	easily.

       -help
	   Prints the online help for this command. All	other valid options
	   are ignored.

OUTPUT
       If the -tmp flag	is included, the following message confirms that a
       Kerberos	ticket cache was created:

	  Wrote	ticket file to /tmp/krb5cc_1000_rENJoZ

       The path	to the cache will vary,	of course.

EXAMPLES
       Most often, this	command	is issued without arguments. The appropriate
       password	is for the person currently logged into	the local system.  The
       ticket's	lifetime is calculated as described in "DESCRIPTION".

	  % klog.krb5
	  Password for user@EXAMPLE.ORG:

       The following example authenticates the user as admin in	the ABC
       Corporation's test cell:

	  % klog.krb5 -principal admin -cell test.abc.com
	  Password for admin@ABC.COM:

       In the following, the issuer requests a ticket lifetime of 104 hours 30
       minutes (4 days 8 hours 30 minutes).

	  % klog.krb5 -lifetime	104:30
	  Password for user@EXAMPLE.ORG:

PRIVILEGE REQUIRED
       None

SEE ALSO
       aklog(1), fs_exportafs(1), pagsh(1), tokens(1)

COPYRIGHT
       IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.

       This documentation is covered by	the IBM	Public License Version 1.0.
       It was converted	from HTML to POD by software written by	Chas Williams
       and Russ	Allbery, based on work by Alf Wachsmann	and Elizabeth Cassell.

OpenAFS				  2016-12-14			  KLOG.KRB5(1)

NAME | SYNOPSIS | DESCRIPTION | CAUTIONS | OPTIONS | OUTPUT | EXAMPLES | PRIVILEGE REQUIRED | SEE ALSO | COPYRIGHT

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