# -*-shell-script-*-
+# This should be sourced by bash (though we welcome changes to make it POSIX sh compliant)
# Shared sh functions for the monkeysphere
#
# Written by
-# Jameson Rollins <jrollins@fifthhorseman.net>
+# Jameson Rollins <jrollins@finestructure.net>
+# Jamie McClelland <jm@mayfirst.org>
+# Daniel Kahn Gillmor <dkg@fifthhorseman.net>
#
# Copyright 2008, released under the GPL, version 3 or later
### COMMON VARIABLES
# managed directories
-ETC="/etc/monkeysphere"
-export ETC
+SYSCONFIGDIR=${MONKEYSPHERE_SYSCONFIGDIR:-"/etc/monkeysphere"}
+export SYSCONFIGDIR
+
+# monkeysphere version
+VERSION=__VERSION__
########################################################################
### UTILITY FUNCTIONS
# failure function. exits with code 255, unless specified otherwise.
failure() {
- echo "$1" >&2
+ [ "$1" ] && echo "$1" >&2
exit ${2:-'255'}
}
-# write output to stderr
+# write output to stderr based on specified LOG_LEVEL the first
+# parameter is the priority of the output, and everything else is what
+# is echoed to stderr
log() {
- echo -n "ms: " >&2
- echo "$@" >&2
-}
+ local priority
+ local level
+ local output
+ local alllevels
+ local found=
+
+ # don't include SILENT in alllevels: it's handled separately
+ # list in decreasing verbosity (all caps).
+ # separate with $IFS explicitly, since we do some fancy footwork
+ # elsewhere.
+ alllevels="DEBUG${IFS}VERBOSE${IFS}INFO${IFS}ERROR"
+
+ # translate lowers to uppers in global log level
+ LOG_LEVEL=$(echo "$LOG_LEVEL" | tr "[:lower:]" "[:upper:]")
+
+ # just go ahead and return if the log level is silent
+ if [ "$LOG_LEVEL" = 'SILENT' ] ; then
+ return
+ fi
+
+ for level in $alllevels ; do
+ if [ "$LOG_LEVEL" = "$level" ] ; then
+ found=true
+ fi
+ done
+ if [ -z "$found" ] ; then
+ # default to INFO:
+ LOG_LEVEL=INFO
+ fi
-loge() {
- echo "$@" >&2
+ # get priority from first parameter, translating all lower to
+ # uppers
+ priority=$(echo "$1" | tr "[:lower:]" "[:upper:]")
+ shift
+
+ # scan over available levels
+ for level in $alllevels ; do
+ # output if the log level matches, set output to true
+ # this will output for all subsequent loops as well.
+ if [ "$LOG_LEVEL" = "$level" ] ; then
+ output=true
+ fi
+ if [ "$priority" = "$level" -a "$output" = 'true' ] ; then
+ echo -n "ms: " >&2
+ echo "$@" >&2
+ fi
+ done
}
# cut out all comments(#) and blank lines from standard input
head --line="$1" "$2" | tail -1
}
+# this is a wrapper for doing lock functions.
+#
+# it lets us depend on either lockfile-progs (preferred) or procmail's
+# lockfile, and should
+lock() {
+ local use_lockfileprogs=true
+ local action="$1"
+ local file="$2"
+
+ if ! ( which lockfile-create >/dev/null 2>/dev/null ) ; then
+ if ! ( which lockfile >/dev/null ); then
+ failure "Neither lockfile-create nor lockfile are in the path!"
+ fi
+ use_lockfileprogs=
+ fi
+
+ case "$action" in
+ create)
+ if [ -n "$use_lockfileprogs" ] ; then
+ lockfile-create "$file" || failure "unable to lock '$file'"
+ else
+ lockfile -r 20 "${file}.lock" || failure "unable to lock '$file'"
+ fi
+ ;;
+ touch)
+ if [ -n "$use_lockfileprogs" ] ; then
+ lockfile-touch --oneshot "$file"
+ else
+ : Nothing to do here
+ fi
+ ;;
+ remove)
+ if [ -n "$use_lockfileprogs" ] ; then
+ lockfile-remove "$file"
+ else
+ rm -f "${file}.lock"
+ fi
+ ;;
+ *)
+ failure "bad argument for lock subfunction '$action'"
+ esac
+}
+
+
+# for portability, between gnu date and BSD date.
+# arguments should be: number longunits format
+
+# e.g. advance_date 20 seconds +%F
+advance_date() {
+ local gnutry
+ local number="$1"
+ local longunits="$2"
+ local format="$3"
+ local shortunits
+
+ # try things the GNU way first
+ if date -d "$number $longunits" "$format" >/dev/null 2>&1; then
+ date -d "$number $longunits" "$format"
+ else
+ # otherwise, convert to (a limited version of) BSD date syntax:
+ case "$longunits" in
+ years)
+ shortunits=y
+ ;;
+ months)
+ shortunits=m
+ ;;
+ weeks)
+ shortunits=w
+ ;;
+ days)
+ shortunits=d
+ ;;
+ hours)
+ shortunits=H
+ ;;
+ minutes)
+ shortunits=M
+ ;;
+ seconds)
+ shortunits=S
+ ;;
+ *)
+ # this is a longshot, and will likely fail; oh well.
+ shortunits="$longunits"
+ esac
+ date "-v+${number}${shortunits}" "$format"
+ fi
+}
+
+
# check that characters are in a string (in an AND fashion).
# used for checking key capability
# check_capability capability a [b...]
md5sum "$1" 2> /dev/null
}
-# 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/:/g'
+# 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'
+}
+
+# prompt for GPG-formatted expiration, and emit result on stdout
+get_gpg_expiration() {
+ local keyExpire
+
+ keyExpire="$1"
+
+ if [ -z "$keyExpire" ]; then
+ cat >&2 <<EOF
+Please specify how long the key should be valid.
+ 0 = key does not expire
+ <n> = key expires in n days
+ <n>w = key expires in n weeks
+ <n>m = key expires in n months
+ <n>y = key expires in n years
+EOF
+ while [ -z "$keyExpire" ] ; do
+ read -p "Key is valid for? (0) " keyExpire
+ if ! test_gpg_expire ${keyExpire:=0} ; then
+ echo "invalid value" >&2
+ unset keyExpire
+ fi
+ done
+ elif ! test_gpg_expire "$keyExpire" ; then
+ failure "invalid key expiration value '$keyExpire'."
+ fi
+
+ echo "$keyExpire"
+}
+
+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
+ local tempfile
file="$1"
string="$2"
# if the string is in the file...
if grep -q -F "$string" "$file" 2> /dev/null ; then
+ tempfile=$(mktemp "${file}.XXXXXXX") || \
+ failure "Unable to make temp file '${file}.XXXXXXX'"
+
# remove the line with the string, and return 0
- grep -v -F "$string" "$file" | sponge "$file"
+ grep -v -F "$string" "$file" >"$tempfile"
+ cat "$tempfile" > "$file"
+ rm "$tempfile"
return 0
# otherwise return 1
else
# remove all lines with MonkeySphere strings in file
remove_monkeysphere_lines() {
local file
+ local tempfile
file="$1"
return 1
fi
+ tempfile=$(mktemp "${file}.XXXXXXX") || \
+ failure "Could not make temporary file '${file}.XXXXXXX'."
+
egrep -v '^MonkeySphere[[:digit:]]{4}(-[[:digit:]]{2}){2}T[[:digit:]]{2}(:[[:digit:]]{2}){2}$' \
- "$file" | sponge "$file"
+ "$file" >"$tempfile"
+ cat "$tempfile" > "$file"
+ rm "$tempfile"
}
# translate ssh-style path variables %h and %u
# 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 uname
local path
+ local stat
local access
local gAccess
local oAccess
- # function to check that an octal corresponds to writability
+ # function to check that the given permission corresponds to writability
is_write() {
- [ "$1" -eq 2 -o "$1" -eq 3 -o "$1" -eq 6 -o "$1" -eq 7 ]
+ [ "$1" = "w" ]
}
- user="$1"
+ uname="$1"
path="$2"
- # return 0 is path does not exist
- [ -e "$path" ] || return 0
+ # return 255 if cannot stat file
+ if ! stat=$(ls -ld "$path" 2>/dev/null) ; then
+ log error "could not stat path '$path'."
+ return 255
+ fi
- owner=$(stat --format '%U' "$path")
- access=$(stat --format '%a' "$path")
- gAccess=$(echo "$access" | cut -c2)
- oAccess=$(echo "$access" | cut -c3)
+ owner=$(echo "$stat" | awk '{ print $3 }')
+ gAccess=$(echo "$stat" | cut -c6)
+ oAccess=$(echo "$stat" | cut -c9)
- # check owner
- if [ "$owner" != "$user" -a "$owner" != 'root' ] ; then
+ # return 1 if path has invalid owner
+ if [ "$owner" != "$uname" -a "$owner" != 'root' ] ; then
+ log error "improper ownership on path '$path'."
return 1
fi
- # check group/other writability
+ # return 2 if path has group or other writability
if is_write "$gAccess" || is_write "$oAccess" ; then
+ log error "improper group or other writability on path '$path'."
return 2
fi
+ # return zero if all clear, or go to next path
if [ "$path" = '/' ] ; then
return 0
else
- check_key_file_permissions $(dirname "$path")
+ check_key_file_permissions "$uname" $(dirname "$path")
fi
}
userID="$1"
- log -n " checking keyserver $KEYSERVER... "
+ log verbose " checking keyserver $KEYSERVER... "
echo 1,2,3,4,5 | \
gpg --quiet --batch --with-colons \
--command-fd 0 --keyserver "$KEYSERVER" \
--search ="$userID" > /dev/null 2>&1
returnCode="$?"
- loge "done."
# if the user is the monkeysphere user, then update the
# monkeysphere user's trustdb
# (see /usr/share/doc/gnupg/DETAILS.gz)
# output is one line for every found key, in the following format:
#
-# flag:fingerprint
+# flag:sshKey
#
# "flag" is an acceptability flag, 0 = ok, 1 = bad
-# "fingerprint" is the fingerprint of the key
+# "sshKey" is the translated gpg key
+#
+# all log output must go to stderr, as stdout is used to pass the
+# flag:sshKey to the calling function.
#
# expects global variable: "MODE"
process_user_id() {
# if the gpg query return code is not 0, return 1
if [ "$?" -ne 0 ] ; then
- log " no primary keys found."
+ log verbose " no primary keys found."
return 1
fi
lastKeyOK=
fingerprint=
- log " primary key found: $keyid"
+ log verbose " primary key found: $keyid"
# if overall key is not valid, skip
if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
- log " - unacceptable primary key validity ($validity)."
+ log debug " - unacceptable primary key validity ($validity)."
continue
fi
# if overall key is disabled, skip
if check_capability "$usage" 'D' ; then
- log " - key disabled."
+ log debug " - key disabled."
continue
fi
# if overall key capability is not ok, skip
if ! check_capability "$usage" $requiredPubCapability ; then
- log " - unacceptable primary key capability ($usage)."
+ log debug " - unacceptable primary key capability ($usage)."
continue
fi
;;
'uid') # user ids
if [ "$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 [ "$keyOK" != true ] ; then
+ log verbose " ! got a user ID after a sub key?! user IDs should only follow primary keys!"
continue
fi
# if an acceptable user ID was already found, skip
- if [ "$uidOK" ] ; then
- continue
- fi
- # if the user ID does not match, skip
- if [ "$(unescape "$uidfpr")" != "$userID" ] ; then
+ if [ "$uidOK" = 'true' ] ; then
continue
fi
- # if the user ID validity is not ok, skip
- if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
+ # if the user ID does matches...
+ if [ "$(echo "$uidfpr" | gpg_unescape)" = "$userID" ] ; then
+ # and the user ID validity is ok
+ if [ "$validity" = 'u' -o "$validity" = 'f' ] ; then
+ # mark user ID acceptable
+ uidOK=true
+ else
+ log debug " - unacceptable user ID validity ($validity)."
+ fi
+ else
continue
fi
- # mark user ID acceptable
- uidOK=true
-
# output a line for the primary key
# 0 = ok, 1 = bad
if [ "$keyOK" -a "$uidOK" -a "$lastKeyOK" ] ; then
- log " * acceptable primary key."
+ log verbose " * acceptable primary key."
if [ -z "$sshKey" ] ; then
- log " ! primary key could not be translated (not RSA or DSA?)."
+ log error " ! primary key could not be translated (not RSA or DSA?)."
else
echo "0:${sshKey}"
fi
else
- log " - unacceptable primary key."
+ log debug " - unacceptable primary key."
if [ -z "$sshKey" ] ; then
- log " ! primary key could not be translated (not RSA or DSA?)."
+ log debug " ! primary key could not be translated (not RSA or DSA?)."
else
echo "1:${sshKey}"
fi
# if sub key validity is not ok, skip
if [ "$validity" != 'u' -a "$validity" != 'f' ] ; then
+ log debug " - unacceptable sub key validity ($validity)."
continue
fi
# if sub key capability is not ok, skip
if ! check_capability "$usage" $requiredCapability ; then
+ log debug " - unacceptable sub key capability ($usage)."
continue
fi
# output a line for the sub key
# 0 = ok, 1 = bad
if [ "$keyOK" -a "$uidOK" -a "$lastKeyOK" ] ; then
- log " * acceptable sub key."
+ log verbose " * acceptable sub key."
if [ -z "$sshKey" ] ; then
- log " ! sub key could not be translated (not RSA or DSA?)."
+ log error " ! sub key could not be translated (not RSA or DSA?)."
else
echo "0:${sshKey}"
fi
else
- log " - unacceptable sub key."
+ log debug " - unacceptable sub key."
if [ -z "$sshKey" ] ; then
- log " ! sub key could not be translated (not RSA or DSA?)."
+ log debug " ! 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 noKey=
local nKeys
local nKeysOK
local ok
local tmpfile
host="$1"
-
- log "processing: $host"
-
userID="ssh://${host}"
+ log verbose "processing: $host"
+
nKeys=0
nKeysOK=0
IFS=$'\n'
- for line in $(process_user_id "ssh://${host}") ; do
+ for line in $(process_user_id "${userID}") ; do
# note that key was found
nKeys=$((nKeys+1))
continue
fi
- # remove the old host key line, and note if removed
- remove_line "$KNOWN_HOSTS" "$sshKey"
+ # remove any old host key line, and note if removed nothing is
+ # removed
+ remove_line "$KNOWN_HOSTS" "$sshKey" || noKey=true
# if key OK, add new host line
if [ "$ok" -eq '0' ] ; then
if [ "$HASH_KNOWN_HOSTS" = 'true' ] ; then
# FIXME: this is really hackish cause ssh-keygen won't
# hash from stdin to stdout
- tmpfile=$(mktemp)
+ tmpfile=$(mktemp ${TMPDIR:-/tmp}/tmp.XXXXXXXXXX)
ssh2known_hosts "$host" "$sshKey" > "$tmpfile"
ssh-keygen -H -f "$tmpfile" 2> /dev/null
cat "$tmpfile" >> "$KNOWN_HOSTS"
else
ssh2known_hosts "$host" "$sshKey" >> "$KNOWN_HOSTS"
fi
+
+ # log if this is a new key to the known_hosts file
+ if [ "$noKey" ] ; then
+ log info "* new key for $host added to known_hosts file."
+ fi
fi
done
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"
+ # create a lockfile on known_hosts:
+ lock create "$KNOWN_HOSTS"
+ # FIXME: we're discarding any pre-existing EXIT trap; is this bad?
+ trap "lock remove $KNOWN_HOSTS" EXIT
# note pre update file checksum
fileCheck="$(file_hash "$KNOWN_HOSTS")"
esac
# touch the lockfile, for good measure.
- lockfile-touch --oneshot "$KNOWN_HOSTS"
+ lock touch "$KNOWN_HOSTS"
done
- # remove the lockfile
- lockfile-remove "$KNOWN_HOSTS"
+ # remove the lockfile and the trap
+ lock remove "$KNOWN_HOSTS"
+ trap - EXIT
# note if the known_hosts file was updated
if [ "$(file_hash "$KNOWN_HOSTS")" != "$fileCheck" ] ; then
- log "known_hosts file updated."
+ log debug "known_hosts file updated."
fi
# if an acceptable host was found, return 0
process_known_hosts() {
local hosts
- log "processing known_hosts file..."
+ log debug "processing known_hosts file..."
hosts=$(meat "$KNOWN_HOSTS" | cut -d ' ' -f 1 | grep -v '^|.*$' | tr , ' ' | tr '\n' ' ')
if [ -z "$hosts" ] ; then
- log "no hosts to process."
+ log debug "no hosts to process."
return
fi
userID="$1"
- log "processing: $userID"
+ log verbose "processing: $userID"
nKeys=0
nKeysOK=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"
+ lock create "$AUTHORIZED_KEYS"
+ # FIXME: we're discarding any pre-existing EXIT trap; is this bad?
+ trap "lock remove $AUTHORIZED_KEYS" EXIT
# note pre update file checksum
fileCheck="$(file_hash "$AUTHORIZED_KEYS")"
esac
# touch the lockfile, for good measure.
- lockfile-touch --oneshot "$AUTHORIZED_KEYS"
+ lock touch "$AUTHORIZED_KEYS"
done
- # remove the lockfile
- lockfile-remove "$AUTHORIZED_KEYS"
+ # remove the lockfile and the trap
+ lock remove "$AUTHORIZED_KEYS"
+ trap - EXIT
# note if the authorized_keys file was updated
if [ "$(file_hash "$AUTHORIZED_KEYS")" != "$fileCheck" ] ; then
- log "authorized_keys file updated."
+ log debug "authorized_keys file updated."
fi
# if an acceptable id was found, return 0
authorizedUserIDs="$1"
- log "processing authorized_user_ids file..."
+ log debug "processing authorized_user_ids file..."
if ! meat "$authorizedUserIDs" > /dev/null ; then
- log "no user IDs to process."
+ log debug " no user IDs to process."
return
fi