.TH MONKEYSPHERE-SERVER "8" "June 2008" "monkeysphere" "User Commands" .SH NAME monkeysphere-server \- Monkeysphere server admin user interface .SH SYNOPSIS .B monkeysphere-server \fIsubcommand\fP [\fIargs\fP] .SH DESCRIPTION \fBMonkeysphere\fP is a framework to leverage the OpenPGP web of trust for OpenSSH authentication. OpenPGP keys are tracked via GnuPG, and added to the authorized_keys and known_hosts files used by OpenSSH for connection authentication. \fBmonkeysphere-server\fP is the Monkeysphere server admin utility. .SH SUBCOMMANDS \fBmonkeysphere-server\fP takes various subcommands: .TP .B update-users [ACCOUNT]... 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(5)), 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'. .TP .B gen-key [HOSTNAME] Generate a OpenPGP key pair for the host. If HOSTNAME is not specified, then the system fully-qualified domain name will be user. An alternate key bit length can be specified with the `-l' or `--length' option (default 2048). An expiration length can be specified with the `-e' or `--expire' option (prompt otherwise). A key revoker fingerprint can be specified with the `-r' or `--revoker' option. `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 diagnostics Review the state of the server with respect to the MonkeySphere in general and report on suggested changes. Among other checks, this includes making sure there is a valid host key, that the key is published, that the sshd configuration points to the right place, and that there are at least some valid identity certifiers. `d' may be used in place of `diagnostics'. .TP .B add-identity-certifier KEYID Instruct system to trust user identity certifications made by KEYID. 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). `a' may be used in place of `add-identity-certifier'. .TP .B remove-identity-certifier KEYID Instruct system to ignore user identity certifications made by KEYID. `r' may be used in place of `remove-identity-certifier'. .TP .B list-identity-certifiers List key IDs trusted by the system to certify user identities. `l' may be used in place of `list-identity-certifiers'. .TP .B gpg-authentication-cmd Execute a gpg command on the gnupg-authentication keyring as the monkeysphere user. This takes a single command (multiple gpg arguments need to be quoted). Use this command with caution, as modifying the gnupg-authentication keyring can affect ssh user authentication. .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. You must also modify the sshd_config on the server 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 (e.g. a server admin) will need to sign the host's key. This is done using standard key signing techniquies, usually by pulling the 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 removed 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 various local user's authorized_user_ids file: $ monkeysphere-server update-users USER Not specifying a specific user will cause all users on the system to updated. sshd can then use these monkeysphere generated authorized_keys files to grant access to user accounts for remote users. 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 revocations and expirations can be processed in a timely manor. .SH ENVIRONMENT The following environment variables will override those specified in the monkeysphere-server.conf configuration file (defaults in parentheses): .TP MONKEYSPHERE_KEYSERVER OpenPGP keyserver to use (subkeys.pgp.net). .TP MONKEYSPHERE_AUTHORIZED_USER_IDS Path to user authorized_user_ids file (%h/.config/monkeysphere/authorized_user_ids). .TP MONKEYSPHERE_RAW_AUTHORIZED_KEYS Path to user-controlled authorized_keys file. `-' means not to add user-controlled file (%h/.ssh/authorized_keys). .TP MONKEYSPHERE_MONKEYSPHERE_USER User to control authentication keychain (monkeysphere). .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 , Daniel Kahn Gillmor .SH SEE ALSO .BR monkeysphere (1), .BR monkeysphere (5), .BR gpg (1), .BR ssh (1)