+passphrase_prompt() {
+ local prompt="$1"
+ local fifo="$2"
+ local PASS
+
+ if [ "$DISPLAY" ] && which "${SSH_ASKPASS:-ssh-askpass}" >/dev/null; then
+ "${SSH_ASKPASS:-ssh-askpass}" "$prompt" > "$fifo"
+ else
+ read -s -p "$prompt" PASS
+ # Uses the builtin echo, so should not put the passphrase into
+ # the process table. I think. --dkg
+ echo "$PASS" > "$fifo"
+ fi
+}
+
+test_gnu_dummy_s2k_extension() {
+
+# this block contains a demonstration private key that has had the
+# primary key stripped out using the GNU S2K extension known as
+# "gnu-dummy" (see /usr/share/doc/gnupg/DETAILS.gz). The subkey is
+# present in cleartext, however.
+
+# openpgp2ssh will be able to deal with this based on whether the
+# local copy of GnuTLS contains read_s2k support that can handle it.
+
+# read up on that here:
+
+# http://lists.gnu.org/archive/html/gnutls-devel/2008-08/msg00005.html
+
+echo "
+-----BEGIN PGP PRIVATE KEY BLOCK-----
+Version: GnuPG v1.4.9 (GNU/Linux)
+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+=CR5w
+-----END PGP PRIVATE KEY BLOCK-----
+" | openpgp2ssh 4129E89D17C1D591 >/dev/null 2>/dev/null
+
+}
+
+# remove all lines with specified string from specified file
+remove_line() {
+ local file
+ local string
+
+ file="$1"
+ string="$2"
+
+ if [ -z "$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
+ local home
+
+ uname="$1"
+ path="$2"
+
+ # get the user's home directory
+ userHome=$(getent passwd "$uname" | cut -d: -f6)
+
+ # translate '%u' to user name
+ path=${path/\%u/"$uname"}
+ # translate '%h' to user home directory
+ path=${path/\%h/"$userHome"}
+
+ echo "$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
+gpg2ssh() {