kadmin Linux Service

kadmin service:

Kerberos V5 database administration program. It provides Kerberos principals, KADM5 policies, and service key tables (keytabs).
Now lets see the manual of kadmin service.
Manual kadmin:
NAME
kadmin - Kerberos V5 database administration program
SYNOPSYS
kadmin [-r realm] [-p principal] [-q query]
[[-c cache_name] | [-k [-t keytab]]] [-w password] [-s admin_server[:port]
kadmin.local [-r realm] [-p principal] [-q query]
[-d dbname] [-e "enc:salt ..."] [-m]
DESCRIPTION
kadmin and kadmin.local are command-line interfaces to the Kerberos V5 KADM5 administration system. Both kadmin and kadmin.local provide identical functionalities; the difference is that kadmin.local runs on the master KDC and does not use Kerberos to authenticate to the database. Except as explicitly noted otherwise, this man page will use kadmin to refer to both versions. kadmin provides for the maintenance of Kerberos principals, KADM5 policies, and service key tables (keytabs).
The remote version uses Kerberos authentication and an encrypted RPC, to operate securely from anywhere on the network. It authenticates to the KADM5 server using the service principal kadmin/admin. If the credentials cache contains a ticket for the kadmin/admin principal, and the -c credentials_cache option is specified, that ticket is used to authenticate to KADM5. Otherwise, the -p and -k options are used to specify the client Kerberos principal name used to authenticate. Once kadmin has determined the principal name, it requests a kadmin/admin Kerberos service ticket from the KDC, and uses that service ticket to authenticate to KADM5.
The local client kadmin.local, is intended to run directly on the master KDC without Kerberos authentication. The local version provides all of the functionality of the now obsolete kdb5_edit(8), except for database dump and load, which is now provided by the kdb5_util(8) utility.
OPTIONS
-r realm
Use realm as the default database realm.
-p principal
Use principal to authenticate. Otherwise, kadmin will append "/admin" to the primary principal name of the default ccache, the value of the USER environment variable, or the username as obtained with getpwuid, in order of preference.
-k Use a keytab to decrypt the KDC response instead of prompting for a password on the TTY. In this case, the default principal will be host/hostname. If there is not a keytab specified with the t option, then the default keytab will be used.
-t keytab
Use keytab to decrypt the KDC response. This can only be used with the -k option.
-c credentials_cache Use credentials_cache as the credentials cache. The credentials_cache should contain a service ticket for the kadmin/admin service; it can be acquired with the kinit(1) program. If this option is not specified, kadmin requests a new service ticket from the KDC, and stores it in its own temporary ccache.
-w password
Use password instead of prompting for one on the TTY. Note: placing the password for a Kerberos principal with administration access into a shell script can be dangerous if unauthorized users gain read access to the script.
-q query
pass query directly to kadmin, which will perform query and then exit. This can be useful for writing scripts.
-d dbname
Specifies the name of the Kerberos database.
-s admin_server[:port]
Specifies the admin server which kadmin should contact.
-m Do not authenticate using a keytab. This option will cause kadmin to prompt for the master database password.
-e enc:salt_list
Sets the list of encryption types and salt types to be used for any new keys created.
DATE FORMAT
Various commands in kadmin can take a variety of date formats, specifying durations or absolute times. Examples of valid formats are:
1 month ago
2 hours ago
400000 seconds ago
last year
this Monday
next Monday
yesterday
tomorrow
now
second Monday
a fortnight ago
3/31/92 10:00:07 PST
January 23, 1987 10:05pm
22:00 GMT
Dates which do not have the "ago" specifier default to being absolute dates, unless they appear in a field where a duration is expected. In that case the time specifier will be interpreted as relative. Specifying "ago" in a duration may result in unexpected behavior.
COMMANDS
add_principal [options] newprinc
creates the principal newprinc, prompting twice for a password. If no policy is specified with the -policy option, and the policy named "default" exists, then that policy is assigned to the principal; note that the assignment of the policy "default" only occurs automatically when a principal is first created, so the policy "default" must already exist for the assignment to occur. This assignment of "default" can be suppressed with the -clearpolicy option. This command requires the add privilege. This command has the aliases addprinc and ank. The options are:
-expire expdate
expiration date of the principal
-pwexpire pwexpdate
password expiration date
-maxlife maxlife
maximum ticket life for the principal
-maxrenewlife maxrenewlife
maximum renewable life of tickets for the principal
-kvno kvno
explicity set the key version number.
-policy policy
policy used by this principal. If no policy is supplied, then if the policy "default" exists and the -clearpolicy is not also specified, then the policy "default" is used; otherwise, the principal will have no policy, and a warning message will be printed.
-clearpolicy
-clearpolicy prevents the policy "default" from being assigned when -policy is not specified. This option has no effect if the policy "default" does not exist.
{-|+}allow_postdated
-allow_postdated prohibits this principal from obtaining postdated tickets. (Sets the KRB5_KDB_DISALLOW_POSTDATED flag.) +allow_postdated clears this flag.
{-|+}allow_forwardable
-allow_forwardable prohibits this principal from obtaining forwardable tickets. (Sets the KRB5_KDB_DISALLOW_FORWARDABLE flag.) +allow_forwardable clears this flag.
{-|+}allow_renewable
-allow_renewable prohibits this principal from obtaining renewable tickets. (Sets the KRB5_KDB_DISALLOW_RENEWABLE flag.) +allow_renewable clears this flag.
{-|+}allow_proxiable
-allow_proxiable prohibits this principal from obtaining proxiable tickets. (Sets the KRB5_KDB_DISALLOW_PROXIABLE flag.) +allow_proxiable clears this flag.
{-|+}allow_dup_skey
-allow_dup_skey Disables user-to-user authentication for this principal by prohibiting this principal from obtaining a session key for another user. (Sets the KRB5_KDB_DISALLOW_DUP_SKEY flag.) +allow_dup_skey clears this flag.
{-|+}requires_preauth
+requires_preauth requires this principal to preauthenticate before being allowed to kinit. (Sets the KRB5_KDB_REQUIRES_PRE_AUTH flag.) -requires_preauth clears this flag.
{-|+}requires_hwauth
+requires_hwauth requires this principal to preauthenticate using a hardware device before being allowed to kinit. (Sets the KRB5_KDB_REQUIRES_HW_AUTH flag.) -requires_hwauth clears this flag.
{-|+}allow_svr
-allow_svr prohibits the issuance of service tickets for this principal. (Sets the KRB5_KDB_DISALLOW_SVR flag.) +allow_svr clears this flag.
{-|+}allow_tgs_req
-allow_tgs_req specifies that a Ticket-Granting Service (TGS) request for a service ticket for this principal is not permitted. This option is useless for most things. +allow_tgs_req clears this flag. The default is +allow_tgs_req. In effect, -allow_tgs_req sets the KRB5_KDB_DISALLOW_TGT_BASED flag on the principal in the database.
{-|+}allow_tix
-allow_tix forbids the issuance of any tickets for this principal. +allow_tix clears this flag. The default is +allow_tix. In effect, -allow_tix sets the KRB5_KDB_DISALLOW_ALL_TIX flag on the principal in the database.
{-|+}needchange
+needchange sets a flag in attributes field to force a password change; -needchange clears it. The default is -needchange. In effect, +needchange sets the KRB5_KDB_REQUIRES_PWCHANGE flag on the principal in the database.
{-|+}password_changing_service
+password_changing_service sets a flag in the attributes field marking this as a password change service principal (useless for most things). -password_changing_service clears the flag. This flag intentionally has a long name. The default is -password_changing_service. In effect, +password_changing_service sets the KRB5_KDB_PWCHANGE_SERVICE flag on the principal in the database.
-randkey
sets the key of the principal to a random value
-pw password
sets the key of the principal to the specified string and does not prompt for a password. Note: using this option in a shell script can be dangerous if unauthorized users gain read access to the script.
-e "enc:salt ..."
uses the specified list of enctype-salttype pairs for setting the key of the principal. The quotes are necessary if there are multiple enctype-salttype pairs. This will not function against kadmin daemons earlier than krb5-1.2.
EXAMPLE:
kadmin: addprinc tlyu/admin
WARNING: no policy specified for "tlyu/admin@BLEEP.COM";
defaulting to no policy.
Enter password for principal tlyu/admin@BLEEP.COM:
Re-enter password for principal tlyu/admin@BLEEP.COM:
Principal "tlyu/admin@BLEEP.COM" created.
kadmin:
ERRORS:
KADM5_AUTH_ADD (requires "add" privilege)
KADM5_BAD_MASK (shouldn't happen)
KADM5_DUP (principal exists already)
KADM5_UNK_POLICY (policy does not exist)
KADM5_PASS_Q_* (password quality violations)
delete_principal [-force] principal
deletes the specified principal from the database. This command prompts for deletion, unless the -force option is given. This command requires the delete privilege. Aliased to delprinc.
EXAMPLE:
kadmin: delprinc mwm_user
Are you sure you want to delete the principal
"mwm_user@BLEEP.COM"? (yes/no): yes
Principal "mwm_user@BLEEP.COM" deleted.
Make sure that you have removed this principal from all ACLs before reusing.
kadmin:
ERRORS:
KADM5_AUTH_DELETE (reequires "delete" privilege)
KADM5_UNK_PRINC (principal does not exist)
modify_principal [options] principal
modifies the specified principal, changing the fields as specified. The options are as above for add_principal, except that password changing and flags related to password changing are forbidden by this command. In addition, the option -clearpolicy will clear the current policy of a principal. This command requires the modify privilege. Aliased to modprinc.
ERRORS:
KADM5_AUTH_MODIFY (requires "modify" privilege)
KADM5_UNK_PRINC (principal does not exist)
KADM5_UNK_POLICY (policy does not exist)
KADM5_BAD_MASK (shouldn't happen)
change_password [options] principal
changes the password of principal. Prompts for a new password if neither -randkey or -pw is specified. Requires the changepw privilege, or that the principal that is running the program to be the same as the one changed. Aliased to cpw. The following options are available:
-randkey
sets the key of the principal to a random value
-pw password
set the password to the specified string. Not recommended.
-e "enc:salt ..."
uses the specified list of enctype-salttype pairs for setting the key of the principal. The quotes are necessary if there are multiple enctype-salttype pairs. This will not function against kadmin daemons earlier than krb5-1.2.
-keepold
Keeps the previous kvno's keys around. There is no easy way to delete the old keys, and this flag is usually not necessary except perhaps for TGS keys. Don't use this flag unless you know what you're doing.
EXAMPLE:
kadmin: cpw systest
Enter password for principal systest@BLEEP.COM:
Re-enter password for principal systest@BLEEP.COM:
Password for systest@BLEEP.COM changed.
kadmin:
ERRORS:
KADM5_AUTH_MODIFY (requires the modify privilege)
KADM5_UNK_PRINC (principal does not exist)
KADM5_PASS_Q_* (password policy violation errors)
KADM5_PADD_REUSE (password is in principal's password history)
KADM5_PASS_TOOSOON (current password minimum life not expired)
get_principal [-terse] principal
gets the attributes of principal. Requires the inquire privilege, or that the principal that is running the the program to be the same as the one being listed. With the -terse option, outputs fields as quoted tab- separated strings. Alias getprinc.
EXAMPLES:
kadmin: getprinc tlyu/admin
Principal: tlyu/admin@BLEEP.COM
Expiration date: [never]
Last password change: Mon Aug 12 14:16:47 EDT 1996
Password expiration date: [none]
Maximum ticket life: 0 days 10:00:00
Maximum renewable life: 7 days 00:00:00
Last modified: Mon Aug 12 14:16:47 EDT 1996 (bjaspan/admin@BLEEP.COM)
Last successful authentication: [never]
Last failed authentication: [never]
Failed password attempts: 0
Number of keys: 2
Key: vno 1, DES cbc mode with CRC-32, no salt
Key: vno 1, DES cbc mode with CRC-32, Version 4
Attributes:
Policy: [none]
kadmin: getprinc -terse systest
systest@BLEEP.COM 3 86400 604800 1
785926535 753241234 785900000
tlyu/admin@BLEEP.COM 786100034 0 0
kadmin:
ERRORS:
KADM5_AUTH_GET (requires the get (inquire) privilege)
KADM5_UNK_PRINC (principal does not exist)
list_principals [expression]
Retrieves all or some principal names. Expression is a shell-style glob expression that can contain the wild-card characters ?, *, and []'s. All principal names matching the expression are printed. If no expression is provided, all principal names are printed. If the expression does not contain an "@" character, an "@" character followed by the local realm is appended to the expression. Requires the list priviledge. Alias listprincs, get_principals, get_princs.
EXAMPLES:
kadmin: listprincs test*
test3@SECURE-TEST.OV.COM
test2@SECURE-TEST.OV.COM
test1@SECURE-TEST.OV.COM
testuser@SECURE-TEST.OV.COM
kadmin:
add_policy [options] policy
adds the named policy to the policy database. Requires the add privilege. Aliased to addpol. The following options are available:
-maxlife time
sets the maximum lifetime of a password
-minlife time
sets the minimum lifetime of a password
-minlength length
sets the minimum length of a password
-minclasses number
sets the minimum number of character classes allowed in a password
-history number
sets the number of past keys kept for a principal
ERRORS:
KADM5_AUTH_ADD (requires the add privilege)
KADM5_DUP (policy already exists)
delete_policy [-force] policy
deletes the named policy. Prompts for confirmation before deletion. The command will fail if the policy is in use by any principals. Requires the delete privilege. Alias delpol.
EXAMPLE:
kadmin: del_policy guests
Are you sure you want to delete the policy "guests"?
(yes/no): yes
kadmin:
ERRORS:
KADM5_AUTH_DELETE (requires the delete privilege)
KADM5_UNK_POLICY (policy does not exist)
KADM5_POLICY_REF (reference count on policy is not zero)
modify_policy [options] policy
modifies the named policy. Options are as above for add_policy. Requires the modify privilege. Alias modpol.
ERRORS:
KADM5_AUTH_MODIFY (requires the modify privilege)
KADM5_UNK_POLICY (policy does not exist)
get_policy [-terse] policy
displays the values of the named policy. Requires the inquire privilege. With the -terse flag, outputs the fields as quoted strings separated by tabs. Alias getpol.
EXAMPLES:
kadmin: get_policy admin
Policy: admin
Maximum password life: 180 days 00:00:00
Minimum password life: 00:00:00
Minimum password length: 6
Minimum number of password character classes: 2
Number of old keys kept: 5
Reference count: 17
kadmin: get_policy -terse admin
admin 15552000 0 6 2 5 17
kadmin:
ERRORS:
KADM5_AUTH_GET (requires the get privilege)
KADM5_UNK_POLICY (policy does not exist)
list_policies [expression]
Retrieves all or some policy names. Expression is a shell-style glob expression that can contain the wildcard characters ?, *, and []'s. All policy names matching the expression are printed. If no expression is provided, all existing policy names are printed. Requires the list priviledge. Alias listpols, get_policies, getpols.
EXAMPLES:
kadmin: listpols
test-pol
dict-only
once-a-min
test-pol-nopw
kadmin: listpols t*
test-pol
test-pol-nopw
kadmin:
ktadd [-k keytab] [-q] [-e keysaltlist]
[principal | -glob princ-exp] [...]
Adds a principal or all principals matching princ-exp to a keytab, randomizing each principal's key in the process. Requires the inquire and changepw privileges. An entry for each of the principal's unique encryption types is added, ignoring multiple keys with the same encryption type but different salt types. If the -k argument is not specified, the default keytab /etc/krb5.keytab is used. If the -q option is specified, less verbose status information is displayed.
The -glob option requires the list privilege. princ-exp follows the same rules described for the list_principals command.
EXAMPLE:
kadmin: ktadd -k /tmp/foo-new-keytab host/foo.mit.edu
Entry for principal host/foo.mit.edu@ATHENA.MIT.EDU with
kvno 3, encryption type DES-CBC-CRC added to keytab
WRFILE:/tmp/foo-new-keytab
kadmin:
ktremove [-k keytab] [-q] principal [kvno | all | old]
Removes entries for the specified principal from a keytab. Requires no permissions, since this does not require database access. If the string "all" is specified, all entries for that principal are removed; if the string "old" is specified, all entries for that principal except those with the highest kvno are removed. Otherwise, the value specified is parsed as an integer, and all entries whose kvno match that integer are removed. If the -k argument is not specifeid, the default keytab /etc/krb5.keytab is used. If the -q option is specified, less verbose status information is displayed.
EXAMPLE:
kadmin: ktremove -k /var/kerberos/krb5kdc/kadm5.keytab kadmin/admin
Entry for principal kadmin/admin with kvno 3 removed
from keytab WRFILE:/var/kerberos/krb5kdc/kadm5.keytab.
kadmin:
FILES
principal.db default name for Kerberos principal database
<dbname>.kadm5 KADM5 administrative database. (This would be "principal.kadm5", if you use the default database name.) Contains policy information.
<dbname>.kadm5.lock lock file for the KADM5 administrative database. This file works backwards from most other lock files. I.e., kadmin will exit with an error if this file does not exist.
kadm5.acl file containing list of principals and their kadmin administrative privileges. See kadmind(8) for a description.
kadm5.keytab keytab file for kadmin/admin principal.
kadm5.dict file containing dictionary of strings explicitly disallowed as passwords.
HISTORY
The kadmin prorgam was originally written by Tom Yu at MIT, as an interface to the OpenVision Kerberos administration program.
SEE ALSO
kerberos(1), kpasswd(1), kadmind(8)
BUGS
Command output needs to be cleaned up.
There is no way to delete a key kept around from a "-keepold" option to a password-changing command, other than to do a password change without the "-keepold" option, which will of course cause problems if the key is a TGS key. There will be more powerful key-manipulation commands in the future.