3 # Shared sh functions for the monkeysphere
6 # Jameson Rollins <jrollins@fifthhorseman.net>
8 # Copyright 2008, released under the GPL, version 3 or later
10 # all-caps variables are meant to be user supplied (ie. from config
11 # file) and are considered global
13 ########################################################################
15 ETC="/etc/monkeysphere"
17 CACHE="/var/cache/monkeysphere"
19 ########################################################################
26 # write output to stderr
32 # cut out all comments(#) and blank lines from standard input
34 grep -v -e "^[[:space:]]*#" -e '^$'
37 # cut a specified line from standard input
39 head --line="$1" | tail -1
42 # retrieve all keys with given user id from keyserver
43 # FIXME: need to figure out how to retrieve all matching keys
49 # if CHECK_KEYSERVER variable set, check the keyserver
51 if [ "CHECK_KEYSERVER" ] ; then
53 gpg --quiet --batch --command-fd 0 --with-colons \
54 --keyserver "$KEYSERVER" \
55 --search ="$userID" >/dev/null 2>&1
57 # otherwise just return true
63 # check that characters are in a string (in an AND fashion).
64 # used for checking key capability
65 # check_capability capability a [b...]
74 if echo "$capability" | grep -q -v "$capcheck" ; then
81 # get the full fingerprint of a key ID
82 get_key_fingerprint() {
87 gpg --list-key --with-colons --fixed-list-mode \
88 --with-fingerprint "$keyID" | grep "$keyID" | \
89 grep '^fpr:' | cut -d: -f10
93 # convert escaped characters from gpg output back into original
95 # FIXME: undo all escape character translation in with-colons gpg output
97 echo "$1" | sed 's/\\x3a/:/'
100 # convert key from gpg to ssh known_hosts format
106 host=$(echo "$2" | sed -e "s|ssh://||")
108 # NOTE: it seems that ssh-keygen -R removes all comment fields from
109 # all lines in the known_hosts file. why?
110 # NOTE: just in case, the COMMENT can be matched with the
112 # '^MonkeySphere[[:digit:]]{4}(-[[:digit:]]{2}){2}T[[:digit:]]{2}(:[[:digit:]]{2}){2}$'
114 gpg --export "$keyID" | \
115 openpgp2ssh "$keyID" | tr -d '\n'
116 echo " MonkeySphere${DATE}"
119 # convert key from gpg to ssh authorized_keys format
120 gpg2authorized_keys() {
127 gpg --export "$keyID" | \
128 openpgp2ssh "$keyID" | tr -d '\n'
129 echo " MonkeySphere${DATE}: ${userID}"
132 # userid and key policy checking
133 # the following checks policy on the returned keys
134 # - checks that full key has appropriate valididy (u|f)
135 # - checks key has specified capability (REQUIRED_*_KEY_CAPABILITY)
136 # - checks that particular desired user id has appropriate validity
137 # see /usr/share/doc/gnupg/DETAILS.gz
138 # expects global variable: "MODE"
142 local requiredCapability
143 local requiredPubCapability
162 # set the required key capability based on the mode
163 if [ "$MODE" = 'known_hosts' ] ; then
164 requiredCapability="$REQUIRED_HOST_KEY_CAPABILITY"
165 elif [ "$MODE" = 'authorized_keys' ] ; then
166 requiredCapability="$REQUIRED_USER_KEY_CAPABILITY"
168 requiredPubCapability=$(echo "$requiredCapability" | tr "[:lower:]" "[:upper:]")
170 # fetch keys from keyserver, return 1 if none found
171 gpg_fetch_userid "$userID" || return 1
173 # output gpg info for (exact) userid and store
174 gpgOut=$(gpg --list-key --fixed-list-mode --with-colon \
175 --with-fingerprint --with-fingerprint \
176 ="$userID" 2>/dev/null)
178 # if the gpg query return code is not 0, return 1
179 if [ "$?" -ne 0 ] ; then
180 log " key not found."
186 # loop over all lines in the gpg output and process.
187 # need to do it this way (as opposed to "while read...") so that
188 # variables set in loop will be visible outside of loop
189 echo "$gpgOut" | cut -d: -f1,2,5,10,12 | \
190 while IFS=: read -r type validity keyid uidfpr usage ; do
191 # process based on record type
193 'pub') # primary keys
194 # new key, wipe the slate
200 # if overall key is not valid, skip
201 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
202 log " unacceptable primary key validity ($validity)."
205 # if overall key is disabled, skip
206 if check_capability "$usage" 'D' ; then
210 # if overall key capability is not ok, skip
211 if ! check_capability "$usage" $requiredPubCapability ; then
212 log " unacceptable primary key capability ($usage)."
216 # mark overall key as ok
219 # mark primary key as ok if capability is ok
220 if check_capability "$usage" $requiredCapability ; then
225 # if the overall key is not ok, skip
226 if [ -z "$keyOK" ] ; then
229 # if an acceptable user ID was already found, skip
230 if [ "$uidOK" ] ; then
233 # if the user ID does not match, skip
234 if [ "$(unescape "$uidfpr")" != "$userID" ] ; then
237 # if the user ID validity is not ok, skip
238 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
242 # mark user ID acceptable
245 # output a line for the primary key
247 if [ "$keyOK" -a "$uidOK" -a "$pubKeyOK" ] ; then
248 log " acceptable key found"
249 echo 0 "$fingerprint"
251 echo 1 "$fingerprint"
255 # unset acceptability of last key
259 # if the overall key is not ok, skip
260 if [ -z "$keyOK" ] ; then
263 # if sub key validity is not ok, skip
264 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
267 # if sub key capability is not ok, skip
268 if ! check_capability "$usage" $requiredCapability ; then
275 'fpr') # key fingerprint
276 fingerprint="$uidfpr"
278 # output a line for the last subkey
280 if [ "$keyOK" -a "$uidOK" -a "$subKeyOK" ] ; then
281 log " acceptable key found"
282 echo 0 "$fingerprint"
284 echo 1 "$fingerprint"
291 # update the cache for userid, and prompt to add file to
292 # authorized_user_ids file if the userid is found in gpg
293 # and not already in file.
302 log "processing userid: '$userID'"
304 # return 1 if there is no output of the user ID processing
305 # ie. no key was found
306 keyCachePath=$(process_user_id "$userID" "$cacheDir")
307 if [ -z "$keyCachePath" ] ; then
311 # check if user ID is in the authorized_user_ids file
312 if ! grep -q "^${userID}\$" "$AUTHORIZED_USER_IDS" ; then
313 read -p "user ID not currently authorized. authorize? [Y|n]: " OK; OK=${OK:=Y}
314 if [ ${OK/y/Y} = 'Y' ] ; then
316 log -n "adding user ID to authorized_user_ids file... "
317 echo "$userID" >> "$AUTHORIZED_USER_IDS"
321 log "authorized_user_ids file untouched."
326 # remove a userid from the authorized_user_ids file
332 log "processing userid: '$userID'"
334 # check if user ID is in the authorized_user_ids file
335 if ! grep -q "^${userID}\$" "$AUTHORIZED_USER_IDS" ; then
336 log "user ID not currently authorized."
340 # remove user ID from file
341 log -n "removing user ID '$userID'... "
342 grep -v "$userID" "$AUTHORIZED_USER_IDS" | sponge "$AUTHORIZED_USER_IDS"
346 # remove all keys from specified key cache from known_hosts file
347 remove_known_hosts_host_keys() {
356 meat "${keyCachePath}/keys" | \
357 while read -r hosts type key comment ; do
358 grep -v "$key" "$USER_KNOWN_HOSTS" | sponge "$USER_KNOWN_HOSTS"
362 # process a host for addition to a known_host file
371 log "processing host: $host"
373 userID="ssh://${host}"
374 process_user_id "ssh://${host}"
376 process_user_id "ssh://${host}" | \
377 while read -r ok key ; do
378 # remove the old host key line
379 remove_known_hosts_host_keys "$key"
380 # if key OK, add new host line
381 if [ "$ok" -eq '0' ] ; then
382 known_hosts_line "$host" "$key" >> "$USER_KNOWN_HOSTS"
387 # process known_hosts file
388 # go through line-by-line, extract each host, and process with the
389 # host processing function
390 process_known_hosts() {
397 # take all the hosts from the known_hosts file (first field),
398 # grep out all the hashed hosts (lines starting with '|')...
399 meat "$USER_KNOWN_HOSTS" | cut -d ' ' -f 1 | grep -v '^|.*$' | \
400 while IFS=, read -r -a hosts ; do
401 # ...and process each host
402 for host in ${hosts[*]} ; do
403 process_host "$host" "$cacheDir"
408 # update an authorized_keys file after first processing the
409 # authorized_user_ids file
410 update_authorized_keys() {
411 local msAuthorizedKeys
412 local userAuthorizedKeys
415 msAuthorizedKeys="$1"
416 userAuthorizedKeys="$2"
419 process_authorized_ids "$AUTHORIZED_USER_IDS" "$cacheDir"
421 # write output key file
422 log "writing monkeysphere authorized_keys file... "
423 touch "$msAuthorizedKeys"
424 if [ "$(ls "$cacheDir")" ] ; then
425 log -n "adding gpg keys... "
426 cat "$cacheDir"/* > "$msAuthorizedKeys"
429 log "no gpg keys to add."
431 if [ "$userAuthorizedKeys" -a -s "$userAuthorizedKeys" ] ; then
432 log -n "adding user authorized_keys file... "
433 cat "$userAuthorizedKeys" >> "$msAuthorizedKeys"
436 log "monkeysphere authorized_keys file generated:"
437 log "$msAuthorizedKeys"
440 # process an authorized_*_ids file
441 # go through line-by-line, extract each userid, and process
442 process_authorized_ids() {
450 process_user_id "$userID" | \
451 while read -r ok key ; do
452 # remove the old host key line
453 remove_authorized_keys_user_keys "$key"
454 # if key OK, add new host line
455 if [ "$ok" -eq '0' ] ; then
456 authorized_keys_line "$userID" "$key" >> "$USER_AUTHORIZED_KEYS"
461 # EXPERIMENTAL (unused) process userids found in authorized_keys file
462 # go through line-by-line, extract monkeysphere userids from comment
463 # fields, and process each userid
464 process_authorized_keys() {
472 # take all the monkeysphere userids from the authorized_keys file
473 # comment field (third field) that starts with "MonkeySphere uid:"
474 # FIXME: needs to handle authorized_keys options (field 0)
475 cat "$authorizedKeys" | \
476 while read -r options keytype key comment ; do
477 # if the comment field is empty, assume the third field was
479 if [ -z "$comment" ] ; then
482 if ! echo "$comment" | grep '^MonkeySphere userID:.*$' ; then
485 userID=$(echo "$comment" | sed -e "/^MonkeySphere userID://")
486 if [ -z "$userID" ] ; then
490 log "processing userid: '$userID'"
491 process_user_id "$userID" "$cacheDir" > /dev/null
495 # retrieve key from web of trust, and set owner trust to "full"
498 # get the key from the key server
499 if ! gpg --keyserver "$KEYSERVER" --recv-key "$keyID" ; then
500 log "could not retrieve key '$keyID'"
504 # get key fingerprint
505 fingerprint=$(get_key_fingerprint "$keyID")
507 # attach a "non-exportable" signature to the key
508 # this is required for the key to have any validity at all
509 # the 'y's on stdin indicates "yes, i really want to sign"
510 echo -e 'y\ny' | gpg --lsign-key --command-fd 0 "$fingerprint"
512 # import "full" trust for fingerprint into gpg
513 echo ${fingerprint}:5: | gpg --import-ownertrust
515 log "owner trust updated."
517 failure "there was a problem changing owner trust."
521 # publish server key to keyserver
522 publish_server_key() {
523 read -p "really publish key to $KEYSERVER? [y|N]: " OK; OK=${OK:=N}
524 if [ ${OK/y/Y} != 'Y' ] ; then
529 # FIXME: need to figure out better way to identify host key
530 # dummy command so as not to publish fakes keys during testing
532 #gpg --send-keys --keyserver "$KEYSERVER" $(hostname -f)
533 echo "NOT PUBLISHED: gpg --send-keys --keyserver $KEYSERVER $(hostname -f)"