1# -*-shell-script-*-
2# This should be sourced by bash (though we welcome changes to make it POSIX sh compliant)
3
4# Monkeysphere authentication setup subcommand
5#
6# The monkeysphere scripts are written by:
7# Jameson Rollins <jrollins@finestructure.net>
8# Jamie McClelland <jm@mayfirst.org>
9# Daniel Kahn Gillmor <dkg@fifthhorseman.net>
10#
11# They are Copyright 2009, and are all released under the GPL,
12# version 3 or later.
13
14setup() {
15    # make all needed directories
16    log debug "checking authentication directory structure..."
17    mkdir -p "${MADATADIR}"
18    chmod 0750 "${MADATADIR}"
19    chgrp "$MONKEYSPHERE_GROUP" "${MADATADIR}"
20    mkdir -p "${MATMPDIR}"
21    chmod 0750 "${MATMPDIR}"
22    chgrp "$MONKEYSPHERE_GROUP" "${MATMPDIR}"
23    mkdir -p "${GNUPGHOME_CORE}"
24    chmod 0700 "${GNUPGHOME_CORE}"
25    mkdir -p "${GNUPGHOME_SPHERE}"
26    chmod 0700 "${GNUPGHOME_SPHERE}"
27    mkdir -p "${SYSDATADIR}"/authorized_keys
28
29    # deliberately replace the config files via truncation
30    # FIXME: should we be dumping to tmp files and then moving atomically?
31    log debug "writing core gpg.conf..."
32    cat >"${GNUPGHOME_CORE}"/gpg.conf <<EOF
33# Monkeysphere trust core GnuPG configuration
34# This file is maintained by the Monkeysphere software.
35# Edits will be overwritten.
36no-greeting
37keyid-format 0xlong
38EOF
39
40    KEYSERVER_OPTIONS=""
41    for anchorfile in "${SYSCONFIGDIR}/monkeysphere-authentication-x509-anchors.crt" "${SYSCONFIGDIR}/monkeysphere-x509-anchors.crt"; do
42        if [ -z "$KEYSERVER_OPTIONS" ] && [ -r "$anchorfile" ] ; then
43            KEYSERVER_OPTIONS="keyserver-options ca-cert-file=$anchorfile"
44            log debug "using $anchorfile for keyserver X.509 anchor"
45        fi
46    done
47
48    log debug "writing sphere gpg.conf..."
49    cat >"${GNUPGHOME_SPHERE}"/gpg.conf <<EOF
50# Monkeysphere trust sphere GnuPG configuration
51# This file is maintained by the Monkeysphere software.
52# Edits will be overwritten.
53no-greeting
54list-options show-uid-validity
55keyid-format 0xlong
56${KEYSERVER_OPTIONS}
57EOF
58
59    # make sure the monkeysphere user owns everything in the sphere
60    # gnupghome
61    log debug "fixing sphere gnupg home ownership..."
62    chown "$MONKEYSPHERE_USER:$MONKEYSPHERE_GROUP" "${GNUPGHOME_SPHERE}" "${GNUPGHOME_SPHERE}"/gpg.conf
63
64    # get fingerprint of core key.  this should be empty on unconfigured systems.
65    local CORE_FPR=$(core_fingerprint)
66    log debug "core fingerprint: $CORE_FPR"
67
68    if [ -z "$CORE_FPR" ] ; then
69	log info "setting up Monkeysphere authentication trust core..."
70
71	local CORE_UID=$(printf "Monkeysphere authentication trust core UID (random string: %s)" $(dd if=/dev/urandom bs=21 count=1 2>/dev/null | perl -MMIME::Base64 -ne 'print encode_base64($_)'))
72
73	printf "generating monkeysphere authentication trust core key:\nsize: %d bits\nuid: '%s'\n" "$CORE_KEYLENGTH" "$CORE_UID" | log debug
74	PEM2OPENPGP_USAGE_FLAGS=certify \
75	    PEM2OPENPGP_NEWKEY=$CORE_KEYLENGTH pem2openpgp "$CORE_UID" \
76	    | gpg_core --import \
77	    || failure "Could not import new key for Monkeysphere authentication trust core"
78
79	# get fingerprint of core key.  should definitely not be empty at this point
80	CORE_FPR=$(core_fingerprint)
81	log debug "core fingerprint: $CORE_FPR"
82	if [ -z "$CORE_FPR" ] ; then
83	    failure "Failed to create Monkeysphere authentication trust core!"
84	fi
85
86    else
87	log verbose "Monkeysphere authentication trust core already exists."
88    fi
89
90    # export the core key to the sphere keyring
91    log debug "exporting core pub key to sphere keyring..."
92    gpg_core --export | gpg_sphere --import
93
94    # ensure that the authentication sphere checker has absolute ownertrust on the expected key.
95    log debug "setting ultimate owner trust on core key in gpg_sphere..."
96    printf "%s:6:\n" "$CORE_FPR" | gpg_sphere --import-ownertrust 2>&1 | log verbose
97    gpg_sphere --export-ownertrust 2>&1 | log debug
98
99    # check the owner trust
100    log debug "checking gpg_sphere owner trust set properly..."
101    local ORIG_TRUST
102    if ORIG_TRUST=$(gpg_sphere --export-ownertrust | grep '^[^#]') ; then
103	if [ "${CORE_FPR}:6:" != "$ORIG_TRUST" ] ; then
104	    failure "Monkeysphere authentication trust sphere should explicitly trust the core.  It does not have proper ownertrust settings."
105	fi
106    else
107	failure "Could not get monkeysphere-authentication trust guidelines."
108	# FIXME: what does this mean?  should we suggest how to fix?
109    fi
110
111    # ensure that we're using the extended trust model (1), and that
112    # our preferences are reasonable (i.e. 3 marginal OR 1 fully
113    # trusted certifications are sufficient to grant full validity.
114    log debug "checking trust model for authentication ..."
115    local TRUST_MODEL=$(gpg_sphere --with-colons --list-keys 2>/dev/null \
116	| head -n1 | grep "^tru:" | cut -d: -f3,6,7)
117    log debug "sphere trust model: $TRUST_MODEL"
118    if [ "$TRUST_MODEL" != '1:3:1' ] ; then
119	failure "monkeysphere-authentication does not have the expected trust model settings."
120	# FIXME: what does this mean?  should we suggest how to fix?
121    fi
122}
123