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
50 log "checking keyserver $KEYSERVER..."
52 gpg --quiet --batch --command-fd 0 --with-colons \
53 --keyserver "$KEYSERVER" \
54 --search ="$userID" >/dev/null 2>&1
55 if [ "$?" = 0 ] ; then
56 log " user ID found on keyserver."
59 log " user ID not found on keyserver."
64 # check that characters are in a string (in an AND fashion).
65 # used for checking key capability
66 # check_capability capability a [b...]
75 if echo "$capability" | grep -q -v "$capcheck" ; then
82 # get the full fingerprint of a key ID
83 get_key_fingerprint() {
88 gpg --list-key --with-colons --fixed-list-mode \
89 --with-fingerprint "$keyID" | grep "$keyID" | \
90 grep '^fpr:' | cut -d: -f10
94 # convert escaped characters from gpg output back into original
96 # FIXME: undo all escape character translation in with-colons gpg output
98 echo "$1" | sed 's/\\x3a/:/'
101 # convert key from gpg to ssh known_hosts format
107 host=$(echo "$2" | sed -e "s|ssh://||")
109 # NOTE: it seems that ssh-keygen -R removes all comment fields from
110 # all lines in the known_hosts file. why?
111 # NOTE: just in case, the COMMENT can be matched with the
113 # '^MonkeySphere[[:digit:]]{4}(-[[:digit:]]{2}){2}T[[:digit:]]{2}(:[[:digit:]]{2}){2}$'
115 gpg --export "$keyID" | \
116 openpgp2ssh "$keyID" | tr -d '\n'
117 echo " MonkeySphere${DATE}"
120 # convert key from gpg to ssh authorized_keys format
121 gpg2authorized_keys() {
128 gpg --export "$keyID" | \
129 openpgp2ssh "$keyID" | tr -d '\n'
130 echo " MonkeySphere${DATE}: ${userID}"
133 # userid and key policy checking
134 # the following checks policy on the returned keys
135 # - checks that full key has appropriate valididy (u|f)
136 # - checks key has specified capability (REQUIRED_*_KEY_CAPABILITY)
137 # - checks that particular desired user id has appropriate validity
138 # see /usr/share/doc/gnupg/DETAILS.gz
139 # expects global variable: "MODE"
143 local requiredCapability
144 local requiredPubCapability
163 # set the required key capability based on the mode
164 if [ "$MODE" = 'known_hosts' ] ; then
165 requiredCapability="$REQUIRED_HOST_KEY_CAPABILITY"
166 elif [ "$MODE" = 'authorized_keys' ] ; then
167 requiredCapability="$REQUIRED_USER_KEY_CAPABILITY"
169 requiredPubCapability=$(echo "$requiredCapability" | tr "[:lower:]" "[:upper:]")
171 # if CHECK_KEYSERVER variable set, check the keyserver
173 if [ "$CHECK_KEYSERVER" = "true" ] ; then
174 gpg_fetch_userid "$userID"
177 # output gpg info for (exact) userid and store
178 gpgOut=$(gpg --list-key --fixed-list-mode --with-colon \
179 --with-fingerprint --with-fingerprint \
180 ="$userID" 2>/dev/null)
182 # if the gpg query return code is not 0, return 1
183 if [ "$?" -ne 0 ] ; then
184 log " key not found."
190 # loop over all lines in the gpg output and process.
191 # need to do it this way (as opposed to "while read...") so that
192 # variables set in loop will be visible outside of loop
193 echo "$gpgOut" | cut -d: -f1,2,5,10,12 | \
194 while IFS=: read -r type validity keyid uidfpr usage ; do
195 # process based on record type
197 'pub') # primary keys
198 # new key, wipe the slate
204 # if overall key is not valid, skip
205 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
206 log " unacceptable primary key validity ($validity)."
209 # if overall key is disabled, skip
210 if check_capability "$usage" 'D' ; then
214 # if overall key capability is not ok, skip
215 if ! check_capability "$usage" $requiredPubCapability ; then
216 log " unacceptable primary key capability ($usage)."
220 # mark overall key as ok
223 # mark primary key as ok if capability is ok
224 if check_capability "$usage" $requiredCapability ; then
229 # if the overall key is not ok, skip
230 if [ -z "$keyOK" ] ; then
233 # if an acceptable user ID was already found, skip
234 if [ "$uidOK" ] ; then
237 # if the user ID does not match, skip
238 if [ "$(unescape "$uidfpr")" != "$userID" ] ; then
241 # if the user ID validity is not ok, skip
242 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
246 # mark user ID acceptable
249 # output a line for the primary key
251 if [ "$keyOK" -a "$uidOK" -a "$pubKeyOK" ] ; then
252 log " acceptable key found"
253 echo 0 "$fingerprint"
255 echo 1 "$fingerprint"
259 # unset acceptability of last key
263 # if the overall key is not ok, skip
264 if [ -z "$keyOK" ] ; then
267 # if sub key validity is not ok, skip
268 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
271 # if sub key capability is not ok, skip
272 if ! check_capability "$usage" $requiredCapability ; then
279 'fpr') # key fingerprint
280 fingerprint="$uidfpr"
282 # output a line for the last subkey
284 if [ "$keyOK" -a "$uidOK" -a "$subKeyOK" ] ; then
285 log " acceptable key found"
286 echo 0 "$fingerprint"
288 echo 1 "$fingerprint"
295 # update the cache for userid, and prompt to add file to
296 # authorized_user_ids file if the userid is found in gpg
297 # and not already in file.
306 log "processing userid: '$userID'"
308 # return 1 if there is no output of the user ID processing
309 # ie. no key was found
310 keyCachePath=$(process_user_id "$userID" "$cacheDir")
311 if [ -z "$keyCachePath" ] ; then
315 # check if user ID is in the authorized_user_ids file
316 if ! grep -q "^${userID}\$" "$AUTHORIZED_USER_IDS" ; then
317 read -p "user ID not currently authorized. authorize? [Y|n]: " OK; OK=${OK:=Y}
318 if [ ${OK/y/Y} = 'Y' ] ; then
320 log -n "adding user ID to authorized_user_ids file... "
321 echo "$userID" >> "$AUTHORIZED_USER_IDS"
325 log "authorized_user_ids file untouched."
330 # remove a userid from the authorized_user_ids file
336 log "processing userid: '$userID'"
338 # check if user ID is in the authorized_user_ids file
339 if ! grep -q "^${userID}\$" "$AUTHORIZED_USER_IDS" ; then
340 log "user ID not currently authorized."
344 # remove user ID from file
345 log -n "removing user ID '$userID'... "
346 grep -v "$userID" "$AUTHORIZED_USER_IDS" | sponge "$AUTHORIZED_USER_IDS"
350 # remove all keys from specified key cache from known_hosts file
351 remove_known_hosts_host_keys() {
360 meat "${keyCachePath}/keys" | \
361 while read -r hosts type key comment ; do
362 grep -v "$key" "$USER_KNOWN_HOSTS" | sponge "$USER_KNOWN_HOSTS"
366 # process a host for addition to a known_host file
375 log "processing host: $host"
377 userID="ssh://${host}"
378 process_user_id "ssh://${host}"
380 process_user_id "ssh://${host}" | \
381 while read -r ok key ; do
382 # remove the old host key line
383 remove_known_hosts_host_keys "$key"
384 # if key OK, add new host line
385 if [ "$ok" -eq '0' ] ; then
386 known_hosts_line "$host" "$key" >> "$USER_KNOWN_HOSTS"
391 # process known_hosts file
392 # go through line-by-line, extract each host, and process with the
393 # host processing function
394 process_known_hosts() {
401 # take all the hosts from the known_hosts file (first field),
402 # grep out all the hashed hosts (lines starting with '|')...
403 meat "$USER_KNOWN_HOSTS" | cut -d ' ' -f 1 | grep -v '^|.*$' | \
404 while IFS=, read -r -a hosts ; do
405 # ...and process each host
406 for host in ${hosts[*]} ; do
407 process_host "$host" "$cacheDir"
412 # update an authorized_keys file after first processing the
413 # authorized_user_ids file
414 update_authorized_keys() {
415 local msAuthorizedKeys
416 local userAuthorizedKeys
419 msAuthorizedKeys="$1"
420 userAuthorizedKeys="$2"
423 process_authorized_ids "$AUTHORIZED_USER_IDS" "$cacheDir"
425 # write output key file
426 log "writing monkeysphere authorized_keys file... "
427 touch "$msAuthorizedKeys"
428 if [ "$(ls "$cacheDir")" ] ; then
429 log -n "adding gpg keys... "
430 cat "$cacheDir"/* > "$msAuthorizedKeys"
433 log "no gpg keys to add."
435 if [ "$userAuthorizedKeys" != "-" -a -s "$userAuthorizedKeys" ] ; then
436 log -n "adding user authorized_keys file... "
437 cat "$userAuthorizedKeys" >> "$msAuthorizedKeys"
440 log "monkeysphere authorized_keys file generated:"
441 log "$msAuthorizedKeys"
444 # process an authorized_*_ids file
445 # go through line-by-line, extract each userid, and process
446 process_authorized_ids() {
454 process_user_id "$userID" | \
455 while read -r ok key ; do
456 # remove the old host key line
457 remove_authorized_keys_user_keys "$key"
458 # if key OK, add new host line
459 if [ "$ok" -eq '0' ] ; then
460 authorized_keys_line "$userID" "$key" >> "$USER_AUTHORIZED_KEYS"
465 # EXPERIMENTAL (unused) process userids found in authorized_keys file
466 # go through line-by-line, extract monkeysphere userids from comment
467 # fields, and process each userid
468 process_authorized_keys() {
476 # take all the monkeysphere userids from the authorized_keys file
477 # comment field (third field) that starts with "MonkeySphere uid:"
478 # FIXME: needs to handle authorized_keys options (field 0)
479 cat "$authorizedKeys" | \
480 while read -r options keytype key comment ; do
481 # if the comment field is empty, assume the third field was
483 if [ -z "$comment" ] ; then
486 if ! echo "$comment" | grep '^MonkeySphere userID:.*$' ; then
489 userID=$(echo "$comment" | sed -e "/^MonkeySphere userID://")
490 if [ -z "$userID" ] ; then
494 log "processing userid: '$userID'"
495 process_user_id "$userID" "$cacheDir" > /dev/null
499 # retrieve key from web of trust, and set owner trust to "full"
502 # get the key from the key server
503 if ! gpg --keyserver "$KEYSERVER" --recv-key "$keyID" ; then
504 log "could not retrieve key '$keyID'"
508 # get key fingerprint
509 fingerprint=$(get_key_fingerprint "$keyID")
511 # attach a "non-exportable" signature to the key
512 # this is required for the key to have any validity at all
513 # the 'y's on stdin indicates "yes, i really want to sign"
514 echo -e 'y\ny' | gpg --lsign-key --command-fd 0 "$fingerprint"
516 # import "full" trust for fingerprint into gpg
517 echo ${fingerprint}:5: | gpg --import-ownertrust
519 log "owner trust updated."
521 failure "there was a problem changing owner trust."
525 # publish server key to keyserver
526 publish_server_key() {
527 read -p "really publish key to $KEYSERVER? [y|N]: " OK; OK=${OK:=N}
528 if [ ${OK/y/Y} != 'Y' ] ; then
533 # FIXME: need to figure out better way to identify host key
534 # dummy command so as not to publish fakes keys during testing
536 #gpg --send-keys --keyserver "$KEYSERVER" $(hostname -f)
537 echo "NOT PUBLISHED: gpg --send-keys --keyserver $KEYSERVER $(hostname -f)"