src/monkeysphere-server



#!/bin/bash

# monkeysphere-server: MonkeySphere server admin tool
#
# The monkeysphere scripts are written by:
# Jameson Rollins <jrollins@fifthhorseman.net>
#
# They are Copyright 2008, and are all released under the GPL, version 3
# or later.

########################################################################
PGRM=$(basename $0)

SHAREDIR=${SHAREDIR:-"/usr/share/monkeysphere"}
export SHAREDIR
. "${SHAREDIR}/common"

# date in UTF format if needed
DATE=$(date -u '+%FT%T')

# unset some environment variables that could screw things up
GREP_OPTIONS=

########################################################################
# FUNCTIONS
########################################################################

usage() {
cat <<EOF
usage: $PGRM <subcommand> [args]
MonkeySphere server admin tool.

subcommands:
  gen-key (g) [HOSTNAME]                generate gpg key for the server
  show-fingerprint (f)                  show server's host key fingerprint
  publish-key (p)                       publish server key to keyserver
  trust-keys (t) KEYID...               mark keyids as trusted

  update-users (s) [USER]...            update users authorized_keys files
  update-user-userids (u) USER UID...   add/update user IDs for a user
  remove-user-userids (r) USER UID...   remove user IDs for a user
  help (h,?)                            this help

EOF
}

# generate server gpg key
gen_key() {
    local hostName

    hostName=${1:-$(hostname --fqdn)}

    # set key defaults
    KEY_TYPE=${KEY_TYPE:-"RSA"}
    KEY_LENGTH=${KEY_LENGTH:-"2048"}
    KEY_USAGE=${KEY_USAGE:-"auth"}
    cat <<EOF
Please specify how long the key should be valid.
         0 = key does not expire
      <n>  = key expires in n days
      <n>w = key expires in n weeks
      <n>m = key expires in n months
      <n>y = key expires in n years
EOF
    read -p "Key is valid for? ($EXPIRE) " EXPIRE; EXPIRE=${EXPIRE:-"0"}

    SERVICE=${SERVICE:-"ssh"}
    USERID=${USERID:-"$SERVICE"://"$hostName"}

    # set key parameters
    keyParameters=$(cat <<EOF
Key-Type: $KEY_TYPE
Key-Length: $KEY_LENGTH
Key-Usage: $KEY_USAGE
Name-Real: $USERID
Expire-Date: $EXPIRE
EOF
)

    # add the revoker field if requested
# FIXME: the 1: below assumes that $REVOKER's key is an RSA key.  why?
# FIXME: why is this marked "sensitive"?  how will this signature ever
# be transmitted to the expected revoker?
    if [ "$REVOKER" ] ; then
    keyParameters="${keyParameters}"$(cat <<EOF

Revoker: 1:$REVOKER sensitive
EOF
)
    fi

    echo "The following key parameters will be used:"
    echo "$keyParameters"

    read -p "generate key? [Y|n]: " OK; OK=${OK:=Y}
    if [ ${OK/y/Y} != 'Y' ] ; then
    failure "aborting."
    fi

    if gpg --list-key ="$USERID" > /dev/null 2>&1 ; then
    failure "key for '$USERID' already exists"
    fi

    # add commit command
    keyParameters="${keyParameters}"$(cat <<EOF

%commit
%echo done
EOF
)

    log -n "generating server key... "
    echo "$keyParameters" | gpg --batch --gen-key
    loge "done."
    fingerprint_server_key
}

fingerprint_server_key() {
    gpg --fingerprint --list-secret-keys =ssh://$(hostname --fqdn)
}

########################################################################
# MAIN
########################################################################

COMMAND="$1"
[ "$COMMAND" ] || failure "Type '$PGRM help' for usage."
shift

# set ms home directory
MS_HOME=${MS_HOME:-"$ETC"}

# load configuration file
MS_CONF=${MS_CONF:-"$MS_HOME"/monkeysphere-server.conf}
[ -e "$MS_CONF" ] && . "$MS_CONF"

# set empty config variable with defaults
GNUPGHOME=${GNUPGHOME:-"${MS_HOME}/gnupg"}
KEYSERVER=${KEYSERVER:-"subkeys.pgp.net"}
CHECK_KEYSERVER=${CHECK_KEYSERVER:="true"}
REQUIRED_USER_KEY_CAPABILITY=${REQUIRED_USER_KEY_CAPABILITY:-"a"}
AUTHORIZED_USER_IDS=${AUTHORIZED_USER_IDS:-"%h/.config/monkeysphere/authorized_user_ids"}
USER_CONTROLLED_AUTHORIZED_KEYS=${USER_CONTROLLED_AUTHORIZED_KEYS:-"%h/.ssh/authorized_keys"}

export GNUPGHOME

# make sure the monkeysphere home directory exists
mkdir -p "${MS_HOME}/authorized_user_ids"
# make sure gpg home exists with proper permissions
mkdir -p -m 0700 "$GNUPGHOME"
# make sure the authorized_keys directory exists
mkdir -p "${CACHE}/authorized_keys"

case $COMMAND in
    'update-users'|'update-user'|'s')
    if [ "$1" ] ; then
        # get users from command line
        unames="$@"
    else
        # or just look at all users if none specified
        unames=$(getent passwd | cut -d: -f1)
    fi

    # loop over users
    for uname in $unames ; do
        MODE="authorized_keys"

        # set authorized_user_ids variable,
        # translate ssh-style path variables
        authorizedUserIDs=$(translate_ssh_variables "$uname" "$AUTHORIZED_USER_IDS")

        # skip user if authorized_user_ids file does not exist
        if [ ! -f "$authorizedUserIDs" ] ; then
        continue
        fi

        log "----- user: $uname -----"

        # temporary authorized_keys file
        AUTHORIZED_KEYS=$(mktemp)

        # skip if the user's authorized_user_ids file is empty
        if [ ! -s "$authorizedUserIDs" ] ; then
        log "authorized_user_ids file '$authorizedUserIDs' is empty."
        continue
        fi

        # process authorized_user_ids file
        log "processing authorized_user_ids file..."
        process_authorized_user_ids "$authorizedUserIDs"

        # add user-controlled authorized_keys file path if specified
        if [ "$USER_CONTROLLED_AUTHORIZED_KEYS" != '-' ] ; then
        userAuthorizedKeys=$(translate_ssh_variables "$uname" "$USER_CONTROLLED_AUTHORIZED_KEYS")
        if [ -f "$userAuthorizedKeys" ] ; then
            log -n "adding user's authorized_keys file... "
            cat "$userAuthorizedKeys" >> "$AUTHORIZED_KEYS"
            loge "done."
        fi
        fi

        # move the temp authorized_keys file into place
        mv -f "$AUTHORIZED_KEYS" "${CACHE}/authorized_keys/${uname}"

        log "authorized_keys file updated."
    done

    log "----- done. -----"
    ;;

    'gen-key'|'g')
    gen_key "$1"
    ;;

    'show-fingerprint'|'f')
    fingerprint_server_key
    ;;

    'publish-key'|'p')
    publish_server_key
    ;;

    'trust-keys'|'trust-key'|'t')
    if [ -z "$1" ] ; then
        failure "You must specify at least one key to trust."
    fi

    # process key IDs
    for keyID ; do
        trust_key "$keyID"
    done
    ;;

    'update-user-userids'|'update-user-userid'|'u')
    uname="$1"
    shift
    if [ -z "$uname" ] ; then
        failure "You must specify user."
    fi
    if [ -z "$1" ] ; then
        failure "You must specify at least one user ID."
    fi

    # set authorized_user_ids variable,
    # translate ssh-style path variables
    authorizedUserIDs=$(translate_ssh_variables "$uname" "$AUTHORIZED_USER_IDS")

        # make sure user's authorized_user_ids file exists
    touch "$authorizedUserIDs"

    # process the user IDs
    for userID ; do
        update_userid "$userID" "$authorizedUserIDs"
    done

    log "Run the following to update user's authorized_keys file:"
    log "$PGRM update-users $uname"
    ;;

    'remove-user-userids'|'remove-user-userid'|'r')
    uname="$1"
    shift
    if [ -z "$uname" ] ; then
        failure "You must specify user."
    fi
    if [ -z "$1" ] ; then
        failure "You must specify at least one user ID."
    fi

    # set authorized_user_ids variable,
    # translate ssh-style path variables
    authorizedUserIDs=$(translate_ssh_variables "$uname" "$AUTHORIZED_USER_IDS")

        # make sure user's authorized_user_ids file exists
    if [ ! -f "$authorizedUserIDs" ] ; then
        failure "authorized_user_ids file '$authorizedUserIDs' does not exist."
    fi

    # process the user IDs
    for userID ; do
        remove_userid "$userID" "$authorizedUserIDs"
    done

    log "Run the following to update user's authorized_keys file:"
    log "$PGRM update-users $uname"
    ;;

    'help'|'h'|'?')
        usage
        ;;

    *)
        failure "Unknown command: '$COMMAND'
Type '$PGRM help' for usage."
        ;;
esac