# -*-shell-script-*-
# This should be sourced by bash (though we welcome changes to make it POSIX sh compliant)

# Monkeysphere authentication setup subcommand
#
# The monkeysphere scripts are written by:
# Jameson Rollins <jrollins@finestructure.net>
# Jamie McClelland <jm@mayfirst.org>
# Daniel Kahn Gillmor <dkg@fifthhorseman.net>
#
# They are Copyright 2009, and are all released under the GPL,
# version 3 or later.

setup() {
    # make the core and the sphere:
    mkdir -p "${SYSDATADIR}"/authentication
    mkdir -p "${GNUPGHOME_SPHERE}"
    mkdir -p "${GNUPGHOME_CORE}"

    # deliberately replace the config files via truncation
    # FIXME: should we be dumping to tmp files and then moving atomically?
    cat >"${GNUPGHOME_CORE}"/gpg.conf <<EOF
# Monkeysphere trust core GnuPG configuration
# This file is maintained by the Monkeysphere software.
# Edits will be overwritten.
no-greeting
list-options show-uid-validity
EOF
    
    cat >"${GNUPGHOME_SPHERE}"/gpg.conf <<EOF
# Monkeysphere trust sphere GnuPG configuration
# This file is maintained by the Monkeysphere software.
# Edits will be overwritten.
no-greeting
primary-keyring ${GNUPGHOME_SPHERE}/pubring.gpg
keyring ${GNUPGHOME_CORE}/pubring.gpg

list-options show-uid-validity
EOF

    # fingerprint of core key.  this should be empty on unconfigured systems.
    local CORE_FPR=$(gpg_core --with-colons --fixed-list-mode --fingerprint --list-secret-key | grep ^fpr: | cut -f10 -d: )

    if [ -z "$CORE_FPR" ] ; then
	log info "Setting up Monkeysphere authentication trust core"

	local CORE_UID=$(printf "Monkeysphere authentication trust core UID (random string: %s)" $(head -c21 </dev/urandom | base64))
    
	local TMPLOC=$(mktemp -d ${MATMPDIR}/tmp.XXXXXXXXXX) || failure "Could not create temporary directory!"
	ssh-keygen -q -b 2048 -t rsa -N'' "${TMPLOC}/authkey" || failure "Could not generate new key for Monkeysphere authentication trust core"

	# FIXME: pem2openpgp currently sets the A flag and a short
	# expiration date.  We should set the C flag and no expiration
	# date.
	< "${TMPLOC}/authkey" pem2openpgp "$CORE_UID" | gpg --import || failure "Could not import new key for Monkeysphere authentication trust core"

	CORE_FPR=$(gpg_core --with-colons --fixed-list-mode --fingerprint --list-secret-key | grep ^fpr: | cut -f10 -d: )
	if [ -z "$CORE_FPR" ] ; then
	    failure "Failed to create Monkeysphere authentication trust core!"
	fi
	
    else 
	log verbose "This system has already set up the Monkeysphere authentication trust core"
    fi


    # ensure that the authentication sphere checker has absolute ownertrust on the expected key.
    printf "%s:6:\n" "$CORE_FPR" | gpg_sphere --import-ownertrust
    local ORIG_TRUST
    if ORIG_TRUST=$(gpg_sphere --export-ownertrust | grep '^[^#]') ; then
	if [ "${CORE_FPR}:6:" != "$ORIG_TRUST" ] ; then
	    failure "Monkeysphere authentication trust sphere should explicitly trust the core.  It does not have proper ownertrust settings."
	fi
    else
	failure "Could not get monkeysphere-authentication trust guidelines."
    fi

    # ensure that we're using the extended trust model (1), and that
    # our preferences are reasonable (i.e. 3 marginal OR 1 fully
    # trusted certifications are sufficient to grant full validity.
    if [ "1:3:1" != $(gpg_sphere --with-colons --fixed-list-mode --list-keys | head -n1 | grep ^tru: cut -f3,6,7 -d:) ] ; then
	failure "monkeysphere-preference does not have the expected trust model settings"
    fi
}