monkeysphere-authentication - Monkeysphere authentication admin tool.
monkeysphere-authentication subcommand [args]
Monkeysphere is a framework to leverage the OpenPGP Web of Trust (WoT)
for key-based authentication. OpenPGP keys are tracked via GnuPG, and
added to the authorized_keys files used by OpenSSH for connection
monkeysphere-authentication is a Monkeysphere server admin utility for
configuring and managing SSH user authentication through the WoT.
monkeysphere-authentication takes various subcommands:
Rebuild the monkeysphere-controlled authorized_keys files. For
each specified account, the user ID’s listed in the account’s
authorized_user_ids file are processed. For each user ID, gpg
will be queried for keys associated with that user ID,
optionally querying a keyserver. If an acceptable key is found
(see KEY ACCEPTABILITY in monkeysphere(7)), the key is added to
the account’s monkeysphere-controlled authorized_keys file. If
the RAW_AUTHORIZED_KEYS variable is set, then a separate
authorized_keys file (usually ~USER/.ssh/authorized_keys) is
appended to the monkeysphere-controlled authorized_keys file.
If no accounts are specified, then all accounts on the system
are processed. ‘u’ may be used in place of ‘update-users’.
Refresh all keys in the monkeysphere-authentication keyring. If
no accounts are specified, then all accounts on the system are
processed. ‘r’ may be used in place of ‘refresh-keys’.
Instruct system to trust user identity certifications made by
KEYID. The key ID will be loaded from the keyserver. A file
may be loaded instead of pulling the key from the keyserver by
specifying the path to the file as the argument, or by
specifying ‘-’ to load from stdin. Using the ‘-n’ or ‘--domain’
option allows you to indicate that you only trust the given
KEYID to make identifications within a specific domain (e.g.
"trust KEYID to certify user identities within the @example.org
domain"). A certifier trust level can be specified with the
‘-t’ or ‘--trust’ option (possible values are ‘marginal’ and
‘full’ (default is ‘full’)). A certifier trust depth can be
specified with the ‘-d’ or ‘--depth’ option (default is 1).
‘c+’ may be used in place of ‘add-id-certifier’.
Instruct system to ignore user identity certifications made by
KEYID. ‘c-’ may be used in place of ‘remove-id-certifier’.
List key IDs trusted by the system to certify user identities.
‘c’ may be used in place of ‘list-id-certifiers’.
Show the monkeysphere version number. ‘v’ may be used in place
help Output a brief usage summary. ‘h’ or ‘?’ may be used in place
setup Setup the server in preparation for Monkeysphere user
authentication. This command is idempotent and run
automatically by the other commands, and should therefore not
usually need to be run manually. ‘s’ may be used in place of
Review the state of the server with respect to authentication.
‘d’ may be used in place of ‘diagnostics’.
Execute a gpg command, as the monkeysphere user, on the
monkeysphere authentication ‘sphere’ keyring. This takes a
single argument (i.e. multiple gpg arguments need to be quoted
all together). Use this command with caution, as modifying the
authentication sphere keyring can affect ssh user
SETUP USER AUTHENTICATION
If the server will handle user authentication through monkeysphere-
generated authorized_keys files, the server must be told which keys
will act as identity certifiers. This is done with the
# monkeysphere-authentication add-id-certifier KEYID
where KEYID is the key ID of the server admin, or whoever’s
certifications should be acceptable to the system for the purposes of
authenticating remote users. You can run this command multiple times
to indicate that multiple certifiers are trusted. You may also specify
a filename instead of a key ID, as long as the file contains a single
OpenPGP public key. Certifiers can be removed with the
remove-id-certifier command, and listed with the list-id-certifiers
A remote user will be granted access to a local account based on the
appropriately-signed and valid keys associated with user IDs listed in
that account’s authorized_user_ids file. By default, the
authorized_user_ids file for an account is
~/.monkeysphere/authorized_user_ids. This can be changed in the
The update-users command is used to generate authorized_keys files for
a local account based on the user IDs listed in the account’s
# monkeysphere-authentication update-users USER
Not specifying USER will cause all accounts on the system to updated.
The ssh server can use these monkeysphere-generated authorized_keys
files to grant access to user accounts for remote users. In order for
sshd to look at the monkeysphere-generated authorized_keys file for
user authentication, the AuthorizedKeysFile parameter must be set in
the sshd_config to point to the monkeysphere-generated authorized_keys
It is recommended to add "monkeysphere-authentication update-users" to
a system crontab, so that user keys are kept up-to-date, and key
revocations and expirations can be processed in a timely manner.
The following environment variables will override those specified in
the config file (defaults in parentheses):
User to control authentication keychain. (monkeysphere)
Set the log level. Can be SILENT, ERROR, INFO, VERBOSE, DEBUG,
in increasing order of verbosity. (INFO)
OpenPGP keyserver to use. (pool.sks-keyservers.net)
Path to user’s authorized_user_ids file. %h gets replaced with
the user’s homedir, %u with the username.
Path to regular ssh-style authorized_keys file to append to
monkeysphere-generated authorized_keys. ‘none’ means not to add
any raw authorized_keys file. %h gets replaced with the user’s
homedir, %u with the username. (%h/.ssh/authorized_keys)
If set to ‘false’, never prompt the user for confirmation.
If set to ‘false’, ignore too-loose permissions on known_hosts,
authorized_keys, and authorized_user_ids files. NOTE: setting
this to false may expose users to abuse by other users on the
System monkeysphere-authentication config file.
If monkeysphere-authentication is configured to query an hkps
keyserver, it will use X.509 Certificate Authority certificates
in this file to validate any X.509 certificates used by the
Monkeysphere-generated user authorized_keys files.
A list of OpenPGP user IDs, one per line. OpenPGP keys with an
exactly-matching User ID (calculated valid by the designated
identity certifiers), will have any valid authorization-capable
keys or subkeys added to the given user’s authorized_keys file.
This man page was written by: Jameson Rollins
<firstname.lastname@example.org>, Daniel Kahn Gillmor
<email@example.com>, Matthew Goins <firstname.lastname@example.org>
monkeysphere(1), monkeysphere-host(8), monkeysphere(7), gpg(1), ssh(1),