wallet

(Client for retrieving secure data from a central server)

SYNOPSIS

wallet [-hv] [-c command] [-f file] [-k principal] [-p port] [-s server] [-S srvtab] [-u principal] command [arg ...]

wallet is a client for the wallet system, which stores or creates secure information such as Kerberos keytabs, associates them with ACLs and other metadata, and allows clients to view and download them. This client provides the user interface to the wallet system for both users and wallet administrators.

The wallet command-line client takes a command and optional arguments on the command line, authenticates to the wallet server using Kerberos, and sends that command and arguments to server. It then reads the results and displays them to the user or stores them in a file. The client itself does not know which commands are valid and which aren't; apart from some special handling of particular commands, it sends all commands to the server to respond to appropriately. This allows additional commands to be added to the wallet system without changing all of the clients.

The primary commands of the wallet system are get, which retrieves some secure data from the wallet, store, which stores some secure data in the wallet, and show, which stores the metadata about an object stored in the wallet. Each object in the wallet has a type, which determines what data the object represents and may determine special handling when downloading or storing that object, and a name. For example, a wallet object for the host/example.com Kerberos keytab would have a type of keytab and a name of host/example.com. The meaning of the name is specific to each type of object.

Most other wallet commands besides those three are only available to wallet administrators. The exception is attribute commands; see ATTRIBUTES. The other commands allow setting ownership and ACLs on objects, creating and destroying objects, creating and destroying ACLs, and adding and removing entries from ACLs. An ACL consists of one or more entries, each of which is a scheme and an identifier. A scheme specifies a way of checking whether a user is authorized. An identifier is some data specific to the scheme that specifies which users are authorized. For example, for the krb5 scheme, the identifier is a principal name and only that principal is authorized by that ACL entry.

To run the wallet command-line client, you must either already have a Kerberos ticket or use the -u option. You can obtain a Kerberos ticket with kinit and see your current Kerberos tickets with klist. The wallet client uses the remctl protocol to talk to the wallet server.

OPTIONS

-c command

The command prefix (remctl type) to use. Normally this is an internal implementation detail and the default (wallet) should be fine. It may sometimes be useful to use a different prefix for testing a different version of the wallet code on the server. This option can also be set in krb5.conf; see CONFIGURATION below.

-f file

This flag is only used in combination with the get and store commands. For get, rather than sending the secure data to standard output (the default), the secure data will be stored in file. For store, the data to be stored will be read from file.

With get, if the object being retrieved is not a keytab object, any current file named output is renamed to outout.bak before the new file is created. outout.new is used as a temporary file and any existing file with that name will be deleted.

If the object being retrieved is a keytab object and the file output already exists, the downloaded keys will be added to the existing keytab file output. Old keys are not removed; you may wish to run kadmin ktremove or an equivalent later to clean up old keys. output.new is still used as a temporary file and any existing file with that name will be deleted.

-k principal

The service principal of the wallet server. The default is to use the host principal for the wallet server. The principal chosen must match one of the keys in the keytab used by remctld on the wallet server. This option can also be set in krb5.conf; see CONFIGURATION below.

-h

Display a brief summary of options and exit. All other valid options and commands are ignored.

-p port

The port to connect to on the wallet server. The default is the default remctl port. This option can also be set in krb5.conf; see CONFIGURATION below.

-S srvtab

This flag is only used in combination with the get command on a keytab object, and must be used in conjunction with the -f flag. After the keytab is saved to the file specified by -f, the DES key for that principal will be extracted and written as a Kerberos v4 srvtab to the file srvtab. Any existing contents of srvtab will be destroyed.

The Kerberos v4 principal name will be generated from the Kerberos v5 principal name using the krb5_524_conv_principal() function of the Kerberos libraries. See its documentation for more information, but briefly (and in the absence of special configuration), the Kerberos v4 principal name will be the same as the Kerberos v5 principal name except that the components are separated by . instead of /; the second component is truncated after the first . if the first component is one of the recognized host-based principals (generally host, imap, pop, or smtp); and the first component is rcmd if the Kerberos v5 principal component is host. The principal name must not contain more than two components.

-s server

The wallet server to connect to. The default may be set when compiling the wallet client. If it isn't, either -s must be given or the server must be set in krb5.conf. See CONFIGURATION below.

-u principal

Rather than using the user's existing ticket cache for authentication, authenticate as principal first and use those credentials for authentication to the wallet server. wallet will prompt for the password for principal. Non-password authentication methods such as PKINIT aren't supported; to use those, run kinit first and use an existing ticket cache.

-v

Display the version of the wallet client and exit. All other valid options and commands are ignored.

COMMANDS

As mentioned above, most commands are only available to wallet administrators. The exceptions are acl check, check, get, store, show, destroy, flag clear, flag set, getattr, setattr, and history. acl check and check can be run by anyone. All of the rest of those commands have their own ACLs except getattr and history, which use the show ACL, setattr, which uses the store ACL, and comment, which uses the owner or show ACL depending on whether one is setting or retrieving the comment. If the appropriate ACL is set, it alone is checked to see if the user has access. Otherwise, destroy, get, store, show, getattr, setattr, history, and comment access is permitted if the user is authorized by the owner ACL of the object.

Administrators can run any command on any object or ACL except for get and store. For get and store, they must still be authorized by either the appropriate specific ACL or the owner ACL.

If the locked flag is set on an object, no commands can be run on that object that change data except the flags commands, nor can the get command be used on that object. show, history, getacl, getattr, and owner, expires, or comment without an argument can still be used on that object.

For more information on attributes, see ATTRIBUTES.

acl add <id> <scheme> <identifier>

Add an entry with <scheme> and <identifier> to the ACL <id>. <id> may be either the name of an ACL or its numeric identifier.

acl check <id>

Check whether an ACL with the ID <id> already exists. If it does, prints yes; if not, prints no.

acl create <name>

Create a new, empty ACL with name <name>. When setting an ACL on an object with a set of entries that don't match an existing ACL, first create a new ACL with acl create, add the appropriate entries to it with acl add, and then set the ACL on an object with the owner or setacl commands.

acl destroy <id>

Destroy the ACL <id>. This ACL must no longer be referenced by any object or the ACL destruction will fail. The special ACL named ADMIN cannot be destroyed.

acl history <id>

Display the history of the ACL <id>. Each change to the ACL (not including changes to the name of the ACL) will be represented by two lines. The first line will have a timestamp of the change followed by a description of the change, and the second line will give the user who made the change and the host from which the change was made.

acl remove <id> <scheme> <identifier>

Remove the entry with <scheme> and <identifier> from the ACL <id>. <id> may be either the name of an ACL or its numeric identifier. The last entry in the special ACL ADMIN cannot be removed to protect against accidental lockout, but administrators can remove themselves from the ADMIN ACL and can leave only a non-functioning entry on the ACL. Use caution when removing entries from the ADMIN ACL.

acl rename <id> <name>

Renames the ACL identified by <id> to <name>. This changes the human-readable name, not the underlying numeric ID, so the ACL's associations with objects will be unchanged. The ADMIN ACL may not be renamed. <id> may be either the current name or the numeric ID. <name> must not be all-numeric. To rename an ACL, the current user must be authorized by the ADMIN ACL.

acl replace <id> <new-id>

Find any objects owned by <id>, and then change their ownership to <new_id> instead. <new-id> should already exist, and may already have some objects owned by it. <id> is not deleted afterwards, though in most cases that is probably your next step. The ADMIN ACL may not be replaced from. <id> and <new-id> may be either the current name or the numeric ID. To replace an ACL, the current user must be authorized by the ADMIN ACL.

acl show <id>

Display the name, numeric ID, and entries of the ACL <id>.

autocreate <type> <name>

Create a new object of type <type> with name <name>. The user must be listed in the default ACL for an object with that type and name, and the object will be created with that default ACL set as the object owner.

Normally, there's no need to run this command directly. It's automatically run when trying to get or store an object that doesn't already exist.

check <type> <name>

Check whether an object of type <type> and name <name> already exists. If it does, prints yes; if not, prints no.

comment <type> <name> [<comment>]

If <comment> is not given, displays the current comment for the object identified by <type> and <name>, or No comment set if none is set.

If <comment> is given, sets the comment on the object identified by <type> and <name> to <comment>. If <comment> is the empty string, clears the comment.

create <type> <name>

Create a new object of type <type> with name <name>. With some backends, this will trigger creation of an entry in an external system as well. The new object will have no ACLs and no owner set, so usually the administrator will want to then set an owner with owner so that the object will be usable.

destroy <type> <name>

Destroy the object identified by <type> and <name>. With some backends, this will trigger destruction of an object in an external system as well.

expires <type> <name> [<expires>]

If <expires> is not given, displays the current expiration of the object identified by <type> and <name>, or No expiration set if none is set. The expiration will be displayed in seconds since epoch.

If <expires> is given, sets the expiration on the object identified by <type> and <name> to that date (and optionally time). <expires> must be in some format that can be parsed by the Perl Date::Parse module. Most common formats are supported; if in doubt, use YYYY-MM-DD HH:MM:SS. If <expires> is the empty string, clears the expiration of the object.

Currently, the expiration of an object is not used.

flag clear <type> <name> <flag>

Clears the flag <flag> on the object identified by <type> and <name>.

flag set <type> <name> <flag>

Sets the flag <flag> on the object identified by <type> and <name>. Recognized flags are locked, which prevents all further actions on that object until the flag is cleared, and unchanging, which tells the object backend to not generate new data on get but instead return the same data as previously returned. The unchanging flag is not meaningful for objects that do not generate new data on the fly.

get <type> <name>

Prints to standard output the data associated with the object identified by <type> and <name>, or stores it in a file if the -f option was given. This may trigger generation of new data and invalidate old data for that object depending on the object type.

If an object with type <type> and name <name> does not already exist when this command is issued (as checked with the check interface), wallet will attempt to automatically create it (using autocreate).

getacl <type> <name> <acl>

Prints the ACL <acl>, which must be one of get, store, show, destroy, or flags, for the object identified by <type> and <name>. Prints No ACL set if that ACL isn't set on that object. Remember that if the get, store, or show ACLs aren't set, authorization falls back to checking the owner ACL. See the owner command for displaying or setting it.

getattr <type> <name> <attr>

Prints the object attribute <attr> for the object identified by <type> and <name>. Attributes are used to store backend-specific information for a particular object type, and <attr> must be an attribute type known to the underlying object implementation. The attribute values, if any, are printed one per line. If the attribute is not set on this object, nothing is printed.

history <type> <name>

Displays the history for the object identified by <type> and <name>. This human-readable output will have two lines for each action that changes the object, plus for any get action. The first line has the timestamp of the action and the action, and the second line gives the user who performed the action and the host from which they performed it.

owner <type> <name> [<owner>]

If <owner> is not given, displays the current owner ACL of the object identified by <type> and <name>, or No owner set if none is set. The result will be the name of an ACL.

If <owner> is given, sets the owner of the object identified by <type> and <name> to <owner>. If <owner> is the empty string, clears the owner of the object.

setacl <type> <name> <acl> <id>

Sets the ACL <acl>, which must be one of get, store, show, destroy, or flags, to <id> on the object identified by <type> and <name>. If <id> is the empty string, clears that ACL on the object.

setattr <type> <name> <attr> <value> [<value> ...]

Sets the object attribute <attr> for the object identified by <type> and <name>. Attributes are used to store backend-specific information for a particular object type, and <attr> must be an attribute type known to the underlying object implementation. To clear the attribute for this object, pass in a <value> of the empty string ('').

show <type> <name>

Displays the current object metadata for the object identified by <type> and <name>. This human-readable output will show the object type and name, the owner, any specific ACLs set on the object, the expiration if any, and the user, remote host, and time when the object was created, last stored, and last downloaded.

store <type> <name> [<data>]

Stores <data> for the object identified by <type> and <name> for later retrieval with get. Not all object types support this. If <data> is not specified on the command line, it will be read from the file specified with -f (if given) or from standard input.

update <type> <name>

Prints to standard output the data associated with the object identified by <type> and <name>, or stores it in a file if the -f option was given. This will generate new data in the object, and only works for objects that support generating new data automatically, such as keytabs or passwords. Types that do not support generating new data will fail and direct you to use get instead.

ATTRIBUTES

Object attributes store additional properties and configuration information for objects stored in the wallet. They are displayed as part of the object data with show, retrieved with getattr, and set with setattr.

Keytab Attributes

Keytab objects support the following attributes:

enctypes

Restricts the generated keytab to a specific set of encryption types. The values of this attribute must be enctype strings recognized by Kerberos (strings like aes256-cts-hmac-sha1-96 or des-cbc-crc). Note that the salt should not be included; since the salt is irrelevant for keytab keys, it will always be set to normal by the wallet.

If this attribute is set, the specified enctype list will be passed to ktadd when get() is called for that keytab. If it is not set, the default set in the KDC will be used.

This attribute is ignored if the unchanging flag is set on a keytab. Keytabs retrieved with unchanging set will contain all keys present in the KDC for that Kerberos principal and therefore may contain different enctypes than those requested by this attribute.

CONFIGURATION

wallet can optionally be configured in the system krb5.conf. It will read the default krb5.conf file for the Kerberos libraries with which it was compiled. To set an option, put the option in the [appdefaults] section. wallet will look for options either at the top level of the [appdefaults] section or in a subsection named wallet. For example, the following fragment of a krb5.conf file would set the default port to 4373 and the default server to wallet.example.org.

    [appdefaults]
        wallet_port = 4373
        wallet = {
            wallet_server = wallet.example.org
        }

The supported options are:

wallet_principal: The service principal of the wallet server. The default is to use the host principal for the wallet server. The principal chosen must match one of the keys in the keytab used by remctld on the wallet server. The -k command-line option overrides this setting.
wallet_port: The port to connect to on the wallet server. The default is the default remctl port. The -p command-line option overrides this setting.
wallet_server: The wallet server to connect to. The -s command-line option overrides this setting. The default may be set when compiling the wallet client. If it isn't, either -s must be given or this parameter must be present in in krb5.conf.
wallet_type: The command prefix (remctl type) to use. Normally this is an internal implementation detail and the default (wallet) should be fine. It may sometimes be useful to use a different prefix for testing a different version of the wallet code on the server. The -c command-line option overrides this setting.

AUTHOR

Russ Allbery <eagle@eyrie.org>

COPYRIGHT AND LICENSE

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. This file is offered as-is, without any warranty.

SPDX-License-Identifier: FSFAP