path: root/man/man8/monkeysphere-server.8

.TH MONKEYSPHERE-SERVER "1" "June 2008" "monkeysphere 0.1" "User Commands"

.SH NAME

monkeysphere-server \- monkeysphere server admin user interface

.SH SYNOPSIS

.B monkeysphere-server \fIcommand\fP [\fIargs\fP]

.SH DESCRIPTION

\fBMonkeySphere\fP is a system to leverage the OpenPGP Web of Trust
for ssh authentication.  OpenPGP keys are tracked via GnuPG, and added
to the ssh authorized_keys and known_hosts files to be used for
authentication of ssh connections.

\fBmonkeysphere-server\fP is the MonkeySphere server admin utility.

.SH SUBCOMMANDS

\fBmonkeysphere-server\fP takes various subcommands:
.TP
.B update-users [USER]...
Update admin-controlled authorized_keys files at
/var/cache/monkeysphere/authorized_keys/USER.  For each specified
user, the user ID's listed in the user's authorized_user_ids file are
processed.  For each user ID, gpg will be queried for keys associated
with that user ID, querying a keyserver if specified.  If a key is
found, it will be converted to an ssh key, and any matching ssh keys
will be removed from the user's authorized_keys file.  If the found
key is acceptable (see KEY ACCEPTABILITY), then the key will be
updated and re-added to the authorized_keys file.  If no gpg key is
found for the user ID, then nothing is done.  If the
RAW_AUTHORIZED_KEYS variable is set, then a user-controlled
authorized_keys file (usually ~USER/.ssh/authorized_keys) is added to
the authorized_keys file.  If no users are specified, then all users
listed in /etc/passwd are processed.  `u' may be used in place of
`update-users.
.TP
.B gen-key
Generate a OpenPGP key pair for the host.  `g' may be used in place of
`gen-key'.
.TP
.B show-fingerprint
Show the fingerprint for the host's OpenPGP key.  `f' may be used in place of
`show-fingerprint'.
.TP
.B publish-key
Publish the host's OpenPGP key to the keyserver.  `p' may be used in
place of `publish-key'.
.TP
.B add-certifier KEYID
Add a certifier key to host keyring.  The key with specified key ID
will be retrieved from the keyserver and imported to the host keyring.
It will then be given a non-exportable trust signature, with default
depth of 1, so that the key may certifier users to log into the
system.  `a' may be used in place of `add-certifier'.
.TP
.B remove-certifier KEYID
Remove a certifier key from the host keyring.  The key with specified
key ID will be removed entirely from the host keyring so that the key
will not longer be able to certify users on the system.  `r' may be
used in place of `remove-certifier'.
.TP
.B list-certifiers
List certifier keys.  `l' may be used in place of `list-certifiers'.
.TP
.B help
Output a brief usage summary.  `h' or `?' may be used in place of
`help'.

.SH SETUP

In order to start using the monkeysphere, you must first generate an
OpenPGP key for the server and convert that key to an ssh key that can
be used by ssh for host authentication.  This can be done with the
\fBgen-key\fP subcommand:

$ monkeysphere-server gen-key

To enable host verification via the monkeysphere, you must then
publish the host's key to the Web of Trust using the \fBpublish-key\fP
command to push the key to a keyserver.  Then modify the sshd_config
to tell sshd where the new server host key is located:

HostKey /var/lib/monkeysphere/ssh_host_rsa_key

In order for users logging into the system to be able to verify the
host via the monkeysphere, at least one person (ie. a server admin)
will need to sign the host's key.  This is done in the same way that
key signing is usually done, by pulling the host's key from the
keyserver, signing the key, and re-publishing the signature.  Once
that is done, users logging into the host will be able to certify the
host's key via the signature of the host admin.

If the server will also handle user authentication through
monkeysphere-generated authorized_keys files, the server must be told
which keys will act as user certifiers.  This is done with the
\fBadd-certifier\fP command:

$ monkeysphere-server add-certifier KEYID

where KEYID is the key ID of the server admin, or whoever's signature
will be certifying users to the system.  Certifiers can be later
remove with the \fBremove-certifier\fP command, and listed with the
\fBlist-certifiers\fP command.

Remote user's will then be granted access to a local user account
based on the appropriately signed and valid keys associated with user
IDs listed in the authorized_user_ids file of the local user.  By
default, the authorized_user_ids file for local users is found in
~/.config/monkeysphere/authorized_user_ids.  This can be changed in
the monkeysphere-server.conf file.

The \fBupdate-users\fP command can then be used to generate
authorized_keys file for local users based on the authorized user IDs
listed in the user's authorized_user_ids file:

$ monkeysphere-server update-users USER

sshd can then use these files to grant access to user accounts for
remote users.  If no user is specified, authorized_keys files will be
generated for all users on the system.  You must also tell sshd to
look at the monkeysphere-generated authorized_keys file for user
authentication by setting the following in the sshd_config:

AuthorizedKeysFile /var/lib/monkeysphere/authorized_keys/%u

It is recommended to add "monkeysphere-server update-users" to a
system crontab, so that user keys are kept up-to-date, and key
revokations and expirations can be processed in a timely manor.

.SH KEY ACCEPTABILITY

GPG keys are considered acceptable if the following criteria are met:
.TP
.B capability
The key must have the "authentication" ("a") usage flag set.
.TP
.B validity
The key must be "fully" valid (ie. signed by a trusted certifier), and
must not be expired or revoked.

.SH FILES

.TP
/etc/monkeysphere/monkeysphere-server.conf
System monkeysphere-server config file.
.TP
/etc/monkeysphere/monkeysphere.conf
System-wide monkeysphere config file.
.TP
/var/lib/monkeysphere/authorized_keys/USER
Monkeysphere-generated user authorized_keys files.
.TP
/var/lib/monkeysphere/ssh_host_rsa_key
Copy of the host's private key in ssh format, suitable for use by
sshd.
.TP
/var/lib/monkeysphere/gnupg-host
Monkeysphere host GNUPG home directory.
.TP
/var/lib/monkeysphere/gnupg-authentication
Monkeysphere authentication GNUPG home directory.

.SH AUTHOR

Written by Jameson Rollins <jrollins@fifthhorseman.net>

.SH SEE ALSO

.BR monkeysphere (1),
.BR gpg (1),
.BR ssh (1)