########################################################################
### UTILITY FUNCTIONS
-error() {
- log "$1"
- ERR=${2:-'1'}
-}
-
+# failure function. exits with code 255, unless specified otherwise.
failure() {
echo "$1" >&2
- exit ${2:-'1'}
+ exit ${2:-'255'}
}
# write output to stderr
# cut out all comments(#) and blank lines from standard input
meat() {
- grep -v -e "^[[:space:]]*#" -e '^$'
+ grep -v -e "^[[:space:]]*#" -e '^$' "$1"
}
# cut a specified line from standard input
cutline() {
- head --line="$1" | tail -1
+ head --line="$1" "$2" | tail -1
}
# check that characters are in a string (in an AND fashion).
return 0
}
-# convert escaped characters from gpg output back into original
-# character
-# FIXME: undo all escape character translation in with-colons gpg output
-unescape() {
- echo "$1" | sed 's/\\x3a/:/'
+# hash of a file
+file_hash() {
+ md5sum "$1" 2> /dev/null
+}
+
+# convert escaped characters in pipeline from gpg output back into
+# original character
+# FIXME: undo all escape character translation in with-colons gpg
+# output
+gpg_unescape() {
+ sed 's/\\x3a/:/g'
+}
+
+# convert nasty chars into gpg-friendly form in pipeline
+# FIXME: escape everything, not just colons!
+gpg_escape() {
+ sed 's/:/\\x3a/g'
}
# remove all lines with specified string from specified file
file="$1"
string="$2"
- if [ "$file" -a "$string" ] ; then
- grep -v "$string" "$file" | sponge "$file"
+ if [ -z "$file" -o -z "$string" ] ; then
+ return 1
+ fi
+
+ if [ ! -e "$file" ] ; then
+ return 1
+ fi
+
+ # if the string is in the file...
+ if grep -q -F "$string" "$file" 2> /dev/null ; then
+ # remove the line with the string, and return 0
+ grep -v -F "$string" "$file" | sponge "$file"
+ return 0
+ # otherwise return 1
+ else
+ return 1
fi
}
+# remove all lines with MonkeySphere strings in file
+remove_monkeysphere_lines() {
+ local file
+
+ file="$1"
+
+ if [ -z "$file" ] ; then
+ return 1
+ fi
+
+ if [ ! -e "$file" ] ; then
+ return 1
+ fi
+
+ egrep -v '^MonkeySphere[[:digit:]]{4}(-[[:digit:]]{2}){2}T[[:digit:]]{2}(:[[:digit:]]{2}){2}$' \
+ "$file" | sponge "$file"
+}
+
# translate ssh-style path variables %h and %u
translate_ssh_variables() {
local uname
echo "$path"
}
+# test that a string to conforms to GPG's expiration format
+test_gpg_expire() {
+ echo "$1" | egrep -q "^[0-9]+[mwy]?$"
+}
+
+# check that a file is properly owned, and that all it's parent
+# directories are not group/other writable
+check_key_file_permissions() {
+ local user
+ local path
+ local access
+ local gAccess
+ local oAccess
+
+ # function to check that an octal corresponds to writability
+ is_write() {
+ [ "$1" -eq 2 -o "$1" -eq 3 -o "$1" -eq 6 -o "$1" -eq 7 ]
+ }
+
+ user="$1"
+ path="$2"
+
+ # return 0 is path does not exist
+ [ -e "$path" ] || return 0
+
+ owner=$(stat --format '%U' "$path")
+ access=$(stat --format '%a' "$path")
+ gAccess=$(echo "$access" | cut -c2)
+ oAccess=$(echo "$access" | cut -c3)
+
+ # check owner
+ if [ "$owner" != "$user" -a "$owner" != 'root' ] ; then
+ return 1
+ fi
+
+ # check group/other writability
+ if is_write "$gAccess" || is_write "$oAccess" ; then
+ return 2
+ fi
+
+ if [ "$path" = '/' ] ; then
+ return 0
+ else
+ check_key_file_permissions $(dirname "$path")
+ fi
+}
+
### CONVERSION UTILITIES
# output the ssh key for a given key ID
gpg --export "$keyID" | openpgp2ssh "$keyID" 2> /dev/null
}
-# output the ssh key for a given secret key ID
-gpgsecret2ssh() {
- local keyID
-
- #keyID="$1" #TMP
- # only use last 16 characters until openpgp2ssh can take all 40 #TMP
- keyID=$(echo "$1" | cut -c 25-) #TMP
-
- gpg --export-secret-key "$keyID" | openpgp2ssh "$keyID" 2> /dev/null
-}
-
# output known_hosts line from ssh key
ssh2known_hosts() {
local host
# (not just first N (5 in this case))
gpg_fetch_userid() {
local userID
+ local returnCode
+
+ if [ "$CHECK_KEYSERVER" != 'true' ] ; then
+ return 0
+ fi
userID="$1"
gpg --quiet --batch --with-colons \
--command-fd 0 --keyserver "$KEYSERVER" \
--search ="$userID" > /dev/null 2>&1
+ returnCode="$?"
loge "done."
-}
-
-# get the full fingerprint of a key ID
-get_key_fingerprint() {
- local keyID
- keyID="$1"
+ # if the user is the monkeysphere user, then update the
+ # monkeysphere user's trustdb
+ if [ $(id -un) = "$MONKEYSPHERE_USER" ] ; then
+ gpg_authentication "--check-trustdb" > /dev/null 2>&1
+ fi
- gpg --list-key --with-colons --fixed-list-mode \
- --with-fingerprint --with-fingerprint "$keyID" | \
- grep '^fpr:' | grep "$keyID" | cut -d: -f10
+ return "$returnCode"
}
########################################################################
# (see /usr/share/doc/gnupg/DETAILS.gz)
# output is one line for every found key, in the following format:
#
-# flag fingerprint
+# flag:fingerprint
#
# "flag" is an acceptability flag, 0 = ok, 1 = bad
# "fingerprint" is the fingerprint of the key
fi
requiredPubCapability=$(echo "$requiredCapability" | tr "[:lower:]" "[:upper:]")
- # if CHECK_KEYSERVER variable set to true, check the keyserver
- # for the user ID
- if [ "$CHECK_KEYSERVER" = "true" ] ; then
- gpg_fetch_userid "$userID"
- fi
+ # fetch the user ID if necessary/requested
+ gpg_fetch_userid "$userID"
# output gpg info for (exact) userid and store
gpgOut=$(gpg --list-key --fixed-list-mode --with-colon \
# if the gpg query return code is not 0, return 1
if [ "$?" -ne 0 ] ; then
- log " - key not found."
+ log " no primary keys found."
return 1
fi
# loop over all lines in the gpg output and process.
- # need to do it this way (as opposed to "while read...") so that
- # variables set in loop will be visible outside of loop
echo "$gpgOut" | cut -d: -f1,2,5,10,12 | \
while IFS=: read -r type validity keyid uidfpr usage ; do
# process based on record type
fi
;;
'uid') # user ids
+ if [ "$lastKey" != pub ] ; then
+ log " - got a user ID after a sub key! user IDs should only follow primary keys!"
+ continue
+ fi
+ # don't bother with a uid if there is no valid or reasonable primary key.
+ if [ "$keyOK" != true ] ; then
+ continue
+ fi
# if an acceptable user ID was already found, skip
if [ "$uidOK" ] ; then
continue
fi
# if the user ID does not match, skip
- if [ "$(unescape "$uidfpr")" != "$userID" ] ; then
+ if [ "$(echo "$uidfpr" | gpg_unescape)" != "$userID" ] ; then
continue
fi
# if the user ID validity is not ok, skip
# output a line for the primary key
# 0 = ok, 1 = bad
if [ "$keyOK" -a "$uidOK" -a "$lastKeyOK" ] ; then
- log " * acceptable key found."
- echo "0:${fingerprint}"
+ log " * acceptable primary key."
+ if [ -z "$sshKey" ] ; then
+ log " ! primary key could not be translated (not RSA or DSA?)."
+ else
+ echo "0:${sshKey}"
+ fi
else
- echo "1:${fingerprint}"
+ log " - unacceptable primary key."
+ if [ -z "$sshKey" ] ; then
+ log " ! primary key could not be translated (not RSA or DSA?)."
+ else
+ echo "1:${sshKey}"
+ fi
fi
;;
'sub') # sub keys
lastKey=sub
lastKeyOK=
fingerprint=
+
+ # don't bother with sub keys if the primary key is not valid
+ if [ "$keyOK" != true ] ; then
+ continue
+ fi
+ # don't bother with sub keys if no user ID is acceptable:
+ if [ "$uidOK" != true ] ; then
+ continue
+ fi
+
# if sub key validity is not ok, skip
if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
continue
'fpr') # key fingerprint
fingerprint="$uidfpr"
+ sshKey=$(gpg2ssh "$fingerprint")
+
# if the last key was the pub key, skip
if [ "$lastKey" = pub ] ; then
continue
fi
-
- # output a line for the last subkey
+
+ # output a line for the sub key
# 0 = ok, 1 = bad
if [ "$keyOK" -a "$uidOK" -a "$lastKeyOK" ] ; then
- log " * acceptable key found."
- echo "0:${fingerprint}"
+ log " * acceptable sub key."
+ if [ -z "$sshKey" ] ; then
+ log " ! sub key could not be translated (not RSA or DSA?)."
+ else
+ echo "0:${sshKey}"
+ fi
else
- echo "1:${fingerprint}"
+ log " - unacceptable sub key."
+ if [ -z "$sshKey" ] ; then
+ log " ! sub key could not be translated (not RSA or DSA?)."
+ else
+ echo "1:${sshKey}"
+ fi
fi
;;
esac
- done
+ done | sort -t: -k1 -n -r
+ # NOTE: this last sort is important so that the "good" keys (key
+ # flag '0') come last. This is so that they take precedence when
+ # being processed in the key files over "bad" keys (key flag '1')
}
# process a single host in the known_host file
process_host_known_hosts() {
local host
local userID
+ local nKeys
+ local nKeysOK
local ok
- local keyid
+ local sshKey
local tmpfile
- local returnCode
-
- # default return code is 1, which assumes no key was found
- returnCode=1
host="$1"
+ userID="ssh://${host}"
- log "processing host: $host"
+ log "processing: $host"
- userID="ssh://${host}"
+ nKeys=0
+ nKeysOK=0
+
+ IFS=$'\n'
+ for line in $(process_user_id "${userID}") ; do
+ # note that key was found
+ nKeys=$((nKeys+1))
- for line in $(process_user_id "ssh://${host}") ; do
ok=$(echo "$line" | cut -d: -f1)
- keyid=$(echo "$line" | cut -d: -f2)
+ sshKey=$(echo "$line" | cut -d: -f2)
- sshKey=$(gpg2ssh "$keyid")
- # remove the old host key line
+ if [ -z "$sshKey" ] ; then
+ continue
+ fi
+
+ # remove the old host key line, and note if removed
remove_line "$KNOWN_HOSTS" "$sshKey"
+
# if key OK, add new host line
if [ "$ok" -eq '0' ] ; then
+ # note that key was found ok
+ nKeysOK=$((nKeysOK+1))
+
# hash if specified
if [ "$HASH_KNOWN_HOSTS" = 'true' ] ; then
# FIXME: this is really hackish cause ssh-keygen won't
else
ssh2known_hosts "$host" "$sshKey" >> "$KNOWN_HOSTS"
fi
- # set return code to be 0, since a key was found
- returnCode=0
fi
- return "$returnCode"
done
- return "$returnCode"
+ # if at least one key was found...
+ if [ "$nKeys" -gt 0 ] ; then
+ # if ok keys were found, return 0
+ if [ "$nKeysOK" -gt 0 ] ; then
+ return 0
+ # else return 2
+ else
+ return 2
+ fi
+ # if no keys were found, return 1
+ else
+ return 1
+ fi
}
# update the known_hosts file for a set of hosts listed on command
# line
update_known_hosts() {
+ local nHosts
+ local nHostsOK
+ local nHostsBAD
+ local fileCheck
local host
- local returnCode
- # default return code is 0, which assumes a key was found for
- # every host. code will be set to 1 if a key is not found for at
- # least one host
- returnCode=0
+ # the number of hosts specified on command line
+ nHosts="$#"
+
+ nHostsOK=0
+ nHostsBAD=0
# set the trap to remove any lockfiles on exit
trap "lockfile-remove $KNOWN_HOSTS" EXIT
# create a lockfile on known_hosts
lockfile-create "$KNOWN_HOSTS"
+ # note pre update file checksum
+ fileCheck="$(file_hash "$KNOWN_HOSTS")"
+
for host ; do
- # process the host, change return code if host key not found
- process_host_known_hosts "$host" || returnCode=1
-
+ # process the host
+ process_host_known_hosts "$host"
+ # note the result
+ case "$?" in
+ 0)
+ nHostsOK=$((nHostsOK+1))
+ ;;
+ 2)
+ nHostsBAD=$((nHostsBAD+1))
+ ;;
+ esac
+
# touch the lockfile, for good measure.
lockfile-touch --oneshot "$KNOWN_HOSTS"
done
# remove the lockfile
lockfile-remove "$KNOWN_HOSTS"
- return "$returnCode"
+ # note if the known_hosts file was updated
+ if [ "$(file_hash "$KNOWN_HOSTS")" != "$fileCheck" ] ; then
+ log "known_hosts file updated."
+ fi
+
+ # if an acceptable host was found, return 0
+ if [ "$nHostsOK" -gt 0 ] ; then
+ return 0
+ # else if no ok hosts were found...
+ else
+ # if no bad host were found then no hosts were found at all,
+ # and return 1
+ if [ "$nHostsBAD" -eq 0 ] ; then
+ return 1
+ # else if at least one bad host was found, return 2
+ else
+ return 2
+ fi
+ fi
}
-# process known_hosts file, going through line-by-line, extract each
-# host, and process with the host processing function
+# process hosts from a known_hosts file
process_known_hosts() {
- local returnCode
+ local hosts
- # default return code is 0, which assumes a key was found for
- # every host. code will be set to 1 if a key is not found for at
- # least one host
- returnCode=0
+ log "processing known_hosts file..."
- # take all the hosts from the known_hosts file (first field), grep
- # out all the hashed hosts (lines starting with '|')...
- for line in $(cat "$KNOWN_HOSTS" | meat | cut -d ' ' -f 1 | grep -v '^|.*$') ; do
- # break up hosts into separate words
- update_known_hosts $(echo "$line" | tr , ' ') || returnCode=1
- done
+ hosts=$(meat "$KNOWN_HOSTS" | cut -d ' ' -f 1 | grep -v '^|.*$' | tr , ' ' | tr '\n' ' ')
- return "$returnCode"
+ if [ -z "$hosts" ] ; then
+ log "no hosts to process."
+ return
+ fi
+
+ # take all the hosts from the known_hosts file (first
+ # field), grep out all the hashed hosts (lines starting
+ # with '|')...
+ update_known_hosts $hosts
}
# process uids for the authorized_keys file
process_uid_authorized_keys() {
local userID
+ local nKeys
+ local nKeysOK
local ok
- local keyid
- local returnCode
-
- # default return code is 1, which assumes no key was found
- returnCode=1
+ local sshKey
userID="$1"
- log "processing user ID: $userID"
+ log "processing: $userID"
+
+ nKeys=0
+ nKeysOK=0
+ IFS=$'\n'
for line in $(process_user_id "$userID") ; do
+ # note that key was found
+ nKeys=$((nKeys+1))
+
ok=$(echo "$line" | cut -d: -f1)
- keyid=$(echo "$line" | cut -d: -f2)
+ sshKey=$(echo "$line" | cut -d: -f2)
+
+ if [ -z "$sshKey" ] ; then
+ continue
+ fi
- sshKey=$(gpg2ssh "$keyid")
# remove the old host key line
remove_line "$AUTHORIZED_KEYS" "$sshKey"
+
# if key OK, add new host line
if [ "$ok" -eq '0' ] ; then
- ssh2authorized_keys "$userID" "$sshKey" >> "$AUTHORIZED_KEYS"
+ # note that key was found ok
+ nKeysOK=$((nKeysOK+1))
- # set return code to be 0, since a key was found
- returnCode=0
+ ssh2authorized_keys "$userID" "$sshKey" >> "$AUTHORIZED_KEYS"
fi
done
- return "$returnCode"
+ # if at least one key was found...
+ if [ "$nKeys" -gt 0 ] ; then
+ # if ok keys were found, return 0
+ if [ "$nKeysOK" -gt 0 ] ; then
+ return 0
+ # else return 2
+ else
+ return 2
+ fi
+ # if no keys were found, return 1
+ else
+ return 1
+ fi
}
# update the authorized_keys files from a list of user IDs on command
# line
update_authorized_keys() {
local userID
- local returnCode
+ local nIDs
+ local nIDsOK
+ local nIDsBAD
+ local fileCheck
+
+ # the number of ids specified on command line
+ nIDs="$#"
- # default return code is 0, which assumes a key was found for
- # every user ID. code will be set to 1 if a key is not found for
- # at least one user ID
- returnCode=0
+ nIDsOK=0
+ nIDsBAD=0
# set the trap to remove any lockfiles on exit
trap "lockfile-remove $AUTHORIZED_KEYS" EXIT
# create a lockfile on authorized_keys
lockfile-create "$AUTHORIZED_KEYS"
+ # note pre update file checksum
+ fileCheck="$(file_hash "$AUTHORIZED_KEYS")"
+
+ # remove any monkeysphere lines from authorized_keys file
+ remove_monkeysphere_lines "$AUTHORIZED_KEYS"
+
for userID ; do
# process the user ID, change return code if key not found for
# user ID
- process_uid_authorized_keys "$userID" || returnCode=1
+ process_uid_authorized_keys "$userID"
+
+ # note the result
+ case "$?" in
+ 0)
+ nIDsOK=$((nIDsOK+1))
+ ;;
+ 2)
+ nIDsBAD=$((nIDsBAD+1))
+ ;;
+ esac
# touch the lockfile, for good measure.
lockfile-touch --oneshot "$AUTHORIZED_KEYS"
# remove the lockfile
lockfile-remove "$AUTHORIZED_KEYS"
- return "$returnCode"
+ # note if the authorized_keys file was updated
+ if [ "$(file_hash "$AUTHORIZED_KEYS")" != "$fileCheck" ] ; then
+ log "authorized_keys file updated."
+ fi
+
+ # if an acceptable id was found, return 0
+ if [ "$nIDsOK" -gt 0 ] ; then
+ return 0
+ # else if no ok ids were found...
+ else
+ # if no bad ids were found then no ids were found at all, and
+ # return 1
+ if [ "$nIDsBAD" -eq 0 ] ; then
+ return 1
+ # else if at least one bad id was found, return 2
+ else
+ return 2
+ fi
+ fi
}
# process an authorized_user_ids file for authorized_keys
process_authorized_user_ids() {
- local userid
- local returnCode
-
- # default return code is 0, and is set to 1 if a key for a user ID
- # is not found
- returnCode=0
+ local line
+ local nline
+ local userIDs
authorizedUserIDs="$1"
- # set the IFS to be newline for parsing the authorized_user_ids
- # file. can't find it in BASH(1) (found it on the net), but it
- # works.
- IFS=$'\n'
- for userid in $(cat "$authorizedUserIDs" | meat) ; do
- update_authorized_keys "$userid" || returnCode=1
- done
-
- return "$returnCode"
-}
-
-# EXPERIMENTAL (unused) process userids found in authorized_keys file
-# go through line-by-line, extract monkeysphere userids from comment
-# fields, and process each userid
-# NOT WORKING
-process_authorized_keys() {
- local authorizedKeys
- local userID
- local returnCode
-
- # default return code is 0, and is set to 1 if a key for a user
- # is not found
- returnCode=0
-
- authorizedKeys="$1"
-
- # take all the monkeysphere userids from the authorized_keys file
- # comment field (third field) that starts with "MonkeySphere uid:"
- # FIXME: needs to handle authorized_keys options (field 0)
- cat "$authorizedKeys" | meat | \
- while read -r options keytype key comment ; do
- # if the comment field is empty, assume the third field was
- # the comment
- if [ -z "$comment" ] ; then
- comment="$key"
- fi
-
- if echo "$comment" | egrep -v -q '^MonkeySphere[[:digit:]]{4}(-[[:digit:]]{2}){2}T[[:digit:]]{2}(:[[:digit:]]{2}){2}' ; then
- continue
- fi
- userID=$(echo "$comment" | awk "{ print $2 }")
- if [ -z "$userID" ] ; then
- continue
- fi
-
- # process the userid
- log "processing userid: '$userID'"
- process_user_id "$userID" > /dev/null || returnCode=1
- done
-
- return "$returnCode"
-}
-
-##################################################
-### GPG HELPER FUNCTIONS
-
-# retrieve key from web of trust, and set owner trust to "full"
-# if key is found.
-trust_key() {
- local keyID
- local trustLevel
-
- keyID="$1"
- trustLevel="$2"
+ log "processing authorized_user_ids file..."
- if [ -z "$keyID" ] ; then
- failure "You must specify key to trust."
+ if ! meat "$authorizedUserIDs" > /dev/null ; then
+ log "no user IDs to process."
+ return
fi
- # get the key from the key server
- if ! gpg --keyserver "$KEYSERVER" --recv-key "$keyID" ; then
- failure "Could not retrieve key '$keyID'."
- fi
+ nline=0
- # get key fingerprint
- fingerprint=$(get_key_fingerprint "$keyID")
-
- echo "key found:"
- gpg --fingerprint "$fingerprint"
-
- while [ -z "$trustLevel" ] ; do
- cat <<EOF
-Please decide how far you trust this user to correctly verify other users' keys
-(by looking at passports, checking fingerprints from different sources, etc.)
-
- 1 = I don't know or won't say
- 2 = I do NOT trust
- 3 = I trust marginally
- 4 = I trust fully
- 5 = I trust ultimately
-
-EOF
- read -p "Your decision? " trustLevel
- if echo "$trustLevel" | grep -v "[1-5]" ; then
- echo "Unknown trust level '$trustLevel'."
- unset trustLevel
- elif [ "$trustLevel" = 'q' ] ; then
- failure "Aborting."
- fi
+ # extract user IDs from authorized_user_ids file
+ IFS=$'\n'
+ for line in $(meat "$authorizedUserIDs") ; do
+ userIDs["$nline"]="$line"
+ nline=$((nline+1))
done
- # attach a "non-exportable" signature to the key
- # this is required for the key to have any validity at all
- # the 'y's on stdin indicates "yes, i really want to sign"
- echo -e 'y\ny' | gpg --quiet --lsign-key --command-fd 0 "$fingerprint"
-
- # index trustLevel by one to difference between level in ui and level
- # internally
- trustLevel=$((trustLevel+1))
-
- # import new owner trust level for key
- echo "${fingerprint}:${trustLevel}:" | gpg --import-ownertrust
- if [ $? = 0 ] ; then
- log "Owner trust updated."
- else
- failure "There was a problem changing owner trust."
- fi
-}
-
-# publish server key to keyserver
-publish_server_key() {
- read -p "really publish key to $KEYSERVER? [y|N]: " OK; OK=${OK:=N}
- if [ ${OK/y/Y} != 'Y' ] ; then
- failure "aborting."
- fi
-
- # publish host key
- # FIXME: need to figure out better way to identify host key
- # dummy command so as not to publish fakes keys during testing
- # eventually:
- #gpg --keyserver "$KEYSERVER" --send-keys $(hostname -f)
- failure "NOT PUBLISHED (to avoid permanent publication errors during monkeysphere development).
-To publish manually, do: gpg --keyserver $KEYSERVER --send-keys $(hostname -f)"
+ update_authorized_keys "${userIDs[@]}"
}