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 ########################################################################
17 ETC="/etc/monkeysphere"
19 CACHE="/var/cache/monkeysphere"
24 ########################################################################
37 # write output to stderr
47 # cut out all comments(#) and blank lines from standard input
49 grep -v -e "^[[:space:]]*#" -e '^$'
52 # cut a specified line from standard input
54 head --line="$1" | tail -1
57 # check that characters are in a string (in an AND fashion).
58 # used for checking key capability
59 # check_capability capability a [b...]
68 if echo "$usage" | grep -q -v "$capcheck" ; then
75 # convert escaped characters from gpg output back into original
77 # FIXME: undo all escape character translation in with-colons gpg output
79 echo "$1" | sed 's/\\x3a/:/'
82 # remove all lines with specified string from specified file
90 if [ "$file" -a "$string" ] ; then
91 grep -v "$string" "$file" | sponge "$file"
95 # translate ssh-style path variables %h and %u
96 translate_ssh_variables() {
103 # get the user's home directory
104 userHome=$(getent passwd "$uname" | cut -d: -f6)
106 # translate '%u' to user name
107 path=${path/\%u/"$uname"}
108 # translate '%h' to user home directory
109 path=${path/\%h/"$userHome"}
114 ### CONVERTION UTILITIES
116 # output the ssh key for a given key ID
121 # only use last 16 characters until openpgp2ssh can take all 40 #TMP
122 keyID=$(echo "$1" | cut -c 25-) #TMP
124 gpg --export "$keyID" | openpgp2ssh "$keyID" 2> /dev/null
127 # output the ssh key for a given secret key ID
132 # only use last 16 characters until openpgp2ssh can take all 40 #TMP
133 keyID=$(echo "$1" | cut -c 25-) #TMP
135 gpg --export-secret-key "$keyID" | openpgp2ssh "$keyID" 2> /dev/null
138 # output known_hosts line from ssh key
147 echo -n "$key" | tr -d '\n'
148 echo " MonkeySphere${DATE}"
151 # output authorized_keys line from ssh key
152 ssh2authorized_keys() {
159 echo -n "$key" | tr -d '\n'
160 echo " MonkeySphere${DATE} ${userID}"
163 # convert key from gpg to ssh known_hosts format
171 # NOTE: it seems that ssh-keygen -R removes all comment fields from
172 # all lines in the known_hosts file. why?
173 # NOTE: just in case, the COMMENT can be matched with the
175 # '^MonkeySphere[[:digit:]]{4}(-[[:digit:]]{2}){2}T[[:digit:]]{2}(:[[:digit:]]{2}){2}$'
177 gpg2ssh "$keyID" | tr -d '\n'
178 echo " MonkeySphere${DATE}"
181 # convert key from gpg to ssh authorized_keys format
182 gpg2authorized_keys() {
189 # NOTE: just in case, the COMMENT can be matched with the
191 # '^MonkeySphere[[:digit:]]{4}(-[[:digit:]]{2}){2}T[[:digit:]]{2}(:[[:digit:]]{2}){2}$'
192 gpg2ssh "$keyID" | tr -d '\n'
193 echo " MonkeySphere${DATE} ${userID}"
198 # retrieve all keys with given user id from keyserver
199 # FIXME: need to figure out how to retrieve all matching keys
200 # (not just first N (5 in this case))
206 log -n " checking keyserver $KEYSERVER... "
208 gpg --quiet --batch --with-colons \
209 --command-fd 0 --keyserver "$KEYSERVER" \
210 --search ="$userID" > /dev/null 2>&1
214 # get the full fingerprint of a key ID
215 get_key_fingerprint() {
220 gpg --list-key --with-colons --fixed-list-mode \
221 --with-fingerprint --with-fingerprint "$keyID" | \
222 grep '^fpr:' | grep "$keyID" | cut -d: -f10
225 ########################################################################
226 ### PROCESSING FUNCTIONS
228 # userid and key policy checking
229 # the following checks policy on the returned keys
230 # - checks that full key has appropriate valididy (u|f)
231 # - checks key has specified capability (REQUIRED_*_KEY_CAPABILITY)
232 # - checks that requested user ID has appropriate validity
233 # (see /usr/share/doc/gnupg/DETAILS.gz)
234 # output is one line for every found key, in the following format:
238 # "flag" is an acceptability flag, 0 = ok, 1 = bad
239 # "fingerprint" is the fingerprint of the key
241 # expects global variable: "MODE"
244 local requiredCapability
245 local requiredPubCapability
260 # set the required key capability based on the mode
261 if [ "$MODE" = 'known_hosts' ] ; then
262 requiredCapability="$REQUIRED_HOST_KEY_CAPABILITY"
263 elif [ "$MODE" = 'authorized_keys' ] ; then
264 requiredCapability="$REQUIRED_USER_KEY_CAPABILITY"
266 requiredPubCapability=$(echo "$requiredCapability" | tr "[:lower:]" "[:upper:]")
268 # if CHECK_KEYSERVER variable set, check the keyserver
270 if [ "$CHECK_KEYSERVER" = "true" ] ; then
271 gpg_fetch_userid "$userID"
274 # output gpg info for (exact) userid and store
275 gpgOut=$(gpg --list-key --fixed-list-mode --with-colon \
276 --with-fingerprint --with-fingerprint \
277 ="$userID" 2>/dev/null)
279 # if the gpg query return code is not 0, return 1
280 if [ "$?" -ne 0 ] ; then
281 log " - key not found."
285 # loop over all lines in the gpg output and process.
286 # need to do it this way (as opposed to "while read...") so that
287 # variables set in loop will be visible outside of loop
288 echo "$gpgOut" | cut -d: -f1,2,5,10,12 | \
289 while IFS=: read -r type validity keyid uidfpr usage ; do
290 # process based on record type
292 'pub') # primary keys
293 # new key, wipe the slate
300 log " primary key found: $keyid"
302 # if overall key is not valid, skip
303 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
304 log " - unacceptable primary key validity ($validity)."
307 # if overall key is disabled, skip
308 if check_capability "$usage" 'D' ; then
309 log " - key disabled."
312 # if overall key capability is not ok, skip
313 if ! check_capability "$usage" $requiredPubCapability ; then
314 log " - unacceptable primary key capability ($usage)."
318 # mark overall key as ok
321 # mark primary key as ok if capability is ok
322 if check_capability "$usage" $requiredCapability ; then
327 # if an acceptable user ID was already found, skip
328 if [ "$uidOK" ] ; then
331 # if the user ID does not match, skip
332 if [ "$(unescape "$uidfpr")" != "$userID" ] ; then
335 # if the user ID validity is not ok, skip
336 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
340 # mark user ID acceptable
343 # output a line for the primary key
345 if [ "$keyOK" -a "$uidOK" -a "$lastKeyOK" ] ; then
346 log " * acceptable key found."
347 echo 0 "$fingerprint"
349 echo 1 "$fingerprint"
353 # unset acceptability of last key
358 # if sub key validity is not ok, skip
359 if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
362 # if sub key capability is not ok, skip
363 if ! check_capability "$usage" $requiredCapability ; then
370 'fpr') # key fingerprint
371 fingerprint="$uidfpr"
373 # if the last key was the pub key, skip
374 if [ "$lastKey" = pub ] ; then
378 # output a line for the last subkey
380 if [ "$keyOK" -a "$uidOK" -a "$lastKeyOK" ] ; then
381 log " * acceptable key found."
382 echo 0 "$fingerprint"
384 echo 1 "$fingerprint"
391 # process hosts in the known_host file
392 process_hosts_known_hosts() {
399 # create a lockfile on known_hosts
400 lockfile-create "$KNOWN_HOSTS"
403 log "processing host: $host"
405 userID="ssh://${host}"
407 process_user_id "ssh://${host}" | \
408 while read -r ok keyid ; do
409 sshKey=$(gpg2ssh "$keyid")
410 # remove the old host key line
411 remove_line "$KNOWN_HOSTS" "$sshKey"
412 # if key OK, add new host line
413 if [ "$ok" -eq '0' ] ; then
415 if [ "$HASH_KNOWN_HOSTS" = 'true' ] ; then
416 # FIXME: this is really hackish cause ssh-keygen won't
417 # hash from stdin to stdout
419 ssh2known_hosts "$host" "$sshKey" > "$tmpfile"
420 ssh-keygen -H -f "$tmpfile" 2> /dev/null
421 cat "$tmpfile" >> "$KNOWN_HOSTS"
422 rm -f "$tmpfile" "${tmpfile}.old"
424 ssh2known_hosts "$host" "$sshKey" >> "$KNOWN_HOSTS"
428 # touch the lockfile, for good measure.
429 lockfile-touch --oneshot "$KNOWN_HOSTS"
432 # remove the lockfile
433 lockfile-remove "$KNOWN_HOSTS"
436 # process uids for the authorized_keys file
437 process_uids_authorized_keys() {
442 # create a lockfile on authorized_keys
443 lockfile-create "$AUTHORIZED_KEYS"
446 log "processing user ID: $userID"
448 process_user_id "$userID" | \
449 while read -r ok keyid ; do
450 sshKey=$(gpg2ssh "$keyid")
451 # remove the old host key line
452 remove_line "$AUTHORIZED_KEYS" "$sshKey"
453 # if key OK, add new host line
454 if [ "$ok" -eq '0' ] ; then
455 ssh2authorized_keys "$userID" "$sshKey" >> "$AUTHORIZED_KEYS"
458 # touch the lockfile, for good measure.
459 lockfile-touch --oneshot "$AUTHORIZED_KEYS"
462 # remove the lockfile
463 lockfile-remove "$AUTHORIZED_KEYS"
466 # process known_hosts file
467 # go through line-by-line, extract each host, and process with the
468 # host processing function
469 process_known_hosts() {
473 # take all the hosts from the known_hosts file (first field),
474 # grep out all the hashed hosts (lines starting with '|')...
475 cat "$KNOWN_HOSTS" | meat | \
476 cut -d ' ' -f 1 | grep -v '^|.*$' | \
477 while IFS=, read -r -a hosts ; do
478 process_hosts_known_hosts ${hosts[@]}
482 # process an authorized_user_ids file for authorized_keys
483 process_authorized_user_ids() {
486 authorizedUserIDs="$1"
488 cat "$authorizedUserIDs" | meat | \
489 while read -r userid ; do
490 process_uids_authorized_keys "$userid"
494 # EXPERIMENTAL (unused) process userids found in authorized_keys file
495 # go through line-by-line, extract monkeysphere userids from comment
496 # fields, and process each userid
498 process_authorized_keys() {
504 # take all the monkeysphere userids from the authorized_keys file
505 # comment field (third field) that starts with "MonkeySphere uid:"
506 # FIXME: needs to handle authorized_keys options (field 0)
507 cat "$authorizedKeys" | meat | \
508 while read -r options keytype key comment ; do
509 # if the comment field is empty, assume the third field was
511 if [ -z "$comment" ] ; then
515 if echo "$comment" | egrep -v -q '^MonkeySphere[[:digit:]]{4}(-[[:digit:]]{2}){2}T[[:digit:]]{2}(:[[:digit:]]{2}){2}' ; then
518 userID=$(echo "$comment" | awk "{ print $2 }")
519 if [ -z "$userID" ] ; then
524 log "processing userid: '$userID'"
525 process_user_id "$userID" > /dev/null
529 ##################################################
530 ### GPG HELPER FUNCTIONS
532 # retrieve key from web of trust, and set owner trust to "full"
535 # get the key from the key server
536 if ! gpg --keyserver "$KEYSERVER" --recv-key "$keyID" ; then
537 failure "Could not retrieve key '$keyID'."
540 # get key fingerprint
541 fingerprint=$(get_key_fingerprint "$keyID")
543 # attach a "non-exportable" signature to the key
544 # this is required for the key to have any validity at all
545 # the 'y's on stdin indicates "yes, i really want to sign"
546 echo -e 'y\ny' | gpg --lsign-key --command-fd 0 "$fingerprint"
548 # import "full" trust for fingerprint into gpg
549 echo ${fingerprint}:5: | gpg --import-ownertrust
551 log "Owner trust updated."
553 failure "There was a problem changing owner trust."
557 # publish server key to keyserver
558 publish_server_key() {
559 read -p "really publish key to $KEYSERVER? [y|N]: " OK; OK=${OK:=N}
560 if [ ${OK/y/Y} != 'Y' ] ; then
565 # FIXME: need to figure out better way to identify host key
566 # dummy command so as not to publish fakes keys during testing
568 #gpg --keyserver "$KEYSERVER" --send-keys $(hostname -f)
569 failure "NOT PUBLISHED (to avoid permanent publication errors during monkeysphere development).
570 To publish manually, do: gpg --keyserver $KEYSERVER --send-keys $(hostname -f)"