X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=src%2Fmonkeysphere-server;h=d2cac0e673570f50630e2a664739c23623796b5e;hb=b7a13e19393e347ba66196a49e972d722d7d4780;hp=db2f428e5a9377caa2628ee7966ec2bb03b8a7ab;hpb=bcf8cd7707dc85f9175d79596a1d0f2c0b3b54a5;p=monkeysphere.git diff --git a/src/monkeysphere-server b/src/monkeysphere-server index db2f428..d2cac0e 100755 --- a/src/monkeysphere-server +++ b/src/monkeysphere-server @@ -4,6 +4,8 @@ # # The monkeysphere scripts are written by: # Jameson Rollins +# Jamie McClelland +# Daniel Kahn Gillmor # # They are Copyright 2008, and are all released under the GPL, version 3 # or later. @@ -11,92 +13,327 @@ ######################################################################## PGRM=$(basename $0) -SHAREDIR=${SHAREDIR:-"/usr/share/monkeysphere"} -export SHAREDIR -. "${SHAREDIR}/common" +SHARE=${MONKEYSPHERE_SHARE:="/usr/share/monkeysphere"} +export SHARE +. "${SHARE}/common" || exit 1 + +VARLIB="/var/lib/monkeysphere" +export VARLIB # date in UTF format if needed DATE=$(date -u '+%FT%T') # unset some environment variables that could screw things up -GREP_OPTIONS= +unset GREP_OPTIONS # default return code -ERR=0 +RETURN=0 ######################################################################## # FUNCTIONS ######################################################################## usage() { -cat < [args] + cat <&2 +usage: $PGRM [options] [args] MonkeySphere server admin tool. subcommands: - update-users (u) [USER]... update users authorized_keys files - gen-key (g) [HOSTNAME] generate gpg key for the server - show-fingerprint (f) show server's host key fingerprint - publish-key (p) publish server's host key to keyserver - trust-key (t) KEYID [LEVEL] set owner trust for keyid - help (h,?) this help + update-users (u) [USER]... update user authorized_keys files + + gen-key (g) [NAME[:PORT]] generate gpg key for the server + --length (-l) BITS key length in bits (2048) + --expire (-e) EXPIRE date to expire + --revoker (-r) FINGERPRINT add a revoker + extend-key (e) EXPIRE extend expiration to EXPIRE + add-hostname (n+) NAME[:PORT] add hostname user ID to server key + revoke-hostname (n-) NAME[:PORT] revoke hostname user ID + show-key (s) output all server host key information + publish-key (p) publish server host key to keyserver + diagnostics (d) report on server monkeysphere status + + add-id-certifier (c+) KEYID import and tsign a certification key + --domain (-n) DOMAIN limit ID certifications to DOMAIN + --trust (-t) TRUST trust level of certifier (full) + --depth (-d) DEPTH trust depth for certifier (1) + remove-id-certifier (c-) KEYID remove a certification key + list-id-certifiers (c) list certification keys + + gpg-authentication-cmd CMD gnupg-authentication command + + help (h,?) this help EOF } +su_monkeysphere_user() { + su --preserve-environment "$MONKEYSPHERE_USER" -- -c "$@" +} + +# function to interact with the host gnupg keyring +gpg_host() { + local returnCode + + GNUPGHOME="$GNUPGHOME_HOST" + export GNUPGHOME + + # NOTE: we supress this warning because we need the monkeysphere + # user to be able to read the host pubring. we realize this might + # be problematic, but it's the simplest solution, without too much + # loss of security. + gpg --no-permission-warning "$@" + returnCode="$?" + + # always reset the permissions on the host pubring so that the + # monkeysphere user can read the trust signatures + chgrp "$MONKEYSPHERE_USER" "${GNUPGHOME_HOST}/pubring.gpg" + chmod g+r "${GNUPGHOME_HOST}/pubring.gpg" + + return "$returnCode" +} + +# function to interact with the authentication gnupg keyring +# FIXME: this function requires basically accepts only a single +# argument because of problems with quote expansion. this needs to be +# fixed/improved. +gpg_authentication() { + GNUPGHOME="$GNUPGHOME_AUTHENTICATION" + export GNUPGHOME + + su_monkeysphere_user "gpg $@" +} + +# output just key fingerprint +fingerprint_server_key() { + gpg_host --list-secret-keys --fingerprint \ + --with-colons --fixed-list-mode 2> /dev/null | \ + grep '^fpr:' | head -1 | cut -d: -f10 +} + +# output key information +show_server_key() { + local fingerprint + local tmpkey + + fingerprint=$(fingerprint_server_key) + gpg_authentication "--fingerprint --list-key --list-options show-unusable-uids $fingerprint" + + # dumping to a file named ' ' so that the ssh-keygen output + # doesn't claim any potentially bogus hostname(s): + tmpkey=$(mktemp -d) + gpg_authentication "--export $fingerprint" | openpgp2ssh "$fingerprint" 2>/dev/null > "$tmpkey/ " + echo -n "ssh fingerprint: " + (cd "$tmpkey" && ssh-keygen -l -f ' ' | awk '{ print $2 }') + rm -rf "$tmpkey" + echo -n "OpenPGP fingerprint: " + echo "$fingerprint" +} + +# update authorized_keys for users +update_users() { + if [ "$1" ] ; then + # get users from command line + unames="$@" + else + # or just look at all users if none specified + unames=$(getent passwd | cut -d: -f1) + fi + + # set mode + MODE="authorized_keys" + + # set gnupg home + GNUPGHOME="$GNUPGHOME_AUTHENTICATION" + + # check to see if the gpg trust database has been initialized + if [ ! -s "${GNUPGHOME}/trustdb.gpg" ] ; then + failure "GNUPG trust database uninitialized. Please see MONKEYSPHERE-SERVER(8)." + fi + + # make sure the authorized_keys directory exists + mkdir -p "${VARLIB}/authorized_keys" + + # loop over users + for uname in $unames ; do + # check all specified users exist + if ! getent passwd "$uname" >/dev/null ; then + log error "----- unknown user '$uname' -----" + continue + fi + + # set authorized_user_ids and raw authorized_keys variables, + # translating ssh-style path variables + authorizedUserIDs=$(translate_ssh_variables "$uname" "$AUTHORIZED_USER_IDS") + rawAuthorizedKeys=$(translate_ssh_variables "$uname" "$RAW_AUTHORIZED_KEYS") + + # if neither is found, skip user + if [ ! -s "$authorizedUserIDs" ] ; then + if [ "$rawAuthorizedKeys" = '-' -o ! -s "$rawAuthorizedKeys" ] ; then + continue + fi + fi + + log verbose "----- user: $uname -----" + + # exit if the authorized_user_ids file is empty + if ! check_key_file_permissions "$uname" "$AUTHORIZED_USER_IDS" ; then + log error "Improper permissions on path '$AUTHORIZED_USER_IDS'." + continue + fi + + # check permissions on the authorized_keys file path + if ! check_key_file_permissions "$uname" "$RAW_AUTHORIZED_KEYS" ; then + log error "Improper permissions on path '$RAW_AUTHORIZED_KEYS'." + continue + fi + + # make temporary directory + TMPDIR=$(mktemp -d) + + # trap to delete temporary directory on exit + trap "rm -rf $TMPDIR" EXIT + + # create temporary authorized_user_ids file + TMP_AUTHORIZED_USER_IDS="${TMPDIR}/authorized_user_ids" + touch "$TMP_AUTHORIZED_USER_IDS" + + # create temporary authorized_keys file + AUTHORIZED_KEYS="${TMPDIR}/authorized_keys" + touch "$AUTHORIZED_KEYS" + + # set restrictive permissions on the temporary files + # FIXME: is there a better way to do this? + chmod 0700 "$TMPDIR" + chmod 0600 "$AUTHORIZED_KEYS" + chmod 0600 "$TMP_AUTHORIZED_USER_IDS" + chown -R "$MONKEYSPHERE_USER" "$TMPDIR" + + # if the authorized_user_ids file exists... + if [ -s "$authorizedUserIDs" ] ; then + # copy user authorized_user_ids file to temporary + # location + cat "$authorizedUserIDs" > "$TMP_AUTHORIZED_USER_IDS" + + # export needed variables + export AUTHORIZED_KEYS + export TMP_AUTHORIZED_USER_IDS + + # process authorized_user_ids file, as monkeysphere + # user + su_monkeysphere_user \ + ". ${SHARE}/common; process_authorized_user_ids $TMP_AUTHORIZED_USER_IDS" + RETURN="$?" + fi + + # add user-controlled authorized_keys file path if specified + if [ "$rawAuthorizedKeys" != '-' -a -s "$rawAuthorizedKeys" ] ; then + log verbose "adding raw authorized_keys file... " + cat "$rawAuthorizedKeys" >> "$AUTHORIZED_KEYS" + fi + + # openssh appears to check the contents of the + # authorized_keys file as the user in question, so the + # file must be readable by that user at least. + # FIXME: is there a better way to do this? + chown root "$AUTHORIZED_KEYS" + chgrp $(getent passwd "$uname" | cut -f4 -d:) "$AUTHORIZED_KEYS" + chmod g+r "$AUTHORIZED_KEYS" + + # move the resulting authorized_keys file into place + mv -f "$AUTHORIZED_KEYS" "${VARLIB}/authorized_keys/${uname}" + + # destroy temporary directory + rm -rf "$TMPDIR" + done +} + # generate server gpg key gen_key() { + local keyType + local keyLength + local keyUsage + local keyExpire + local revoker local hostName + local userID + local keyParameters + local fingerprint + + # set default key parameter values + keyType="RSA" + keyLength="2048" + keyUsage="auth" + keyExpire= + revoker= + + # get options + TEMP=$(getopt -o e:l:r -l expire:,length:,revoker: -n "$PGRM" -- "$@") + + if [ $? != 0 ] ; then + exit 1 + fi + + # Note the quotes around `$TEMP': they are essential! + eval set -- "$TEMP" + + while true ; do + case "$1" in + -l|--length) + keyLength="$2" + shift 2 + ;; + -e|--expire) + keyExpire="$2" + shift 2 + ;; + -r|--revoker) + revoker="$2" + shift 2 + ;; + --) + shift + ;; + *) + break + ;; + esac + done hostName=${1:-$(hostname --fqdn)} - service=${SERVICE:-"ssh"} - userID="${service}://${hostName}" + userID="ssh://${hostName}" - if gpg --list-key ="$userID" > /dev/null 2>&1 ; then + # check for presense of key with user ID + if gpg_host --list-key ="$userID" > /dev/null 2>&1 ; then failure "Key for '$userID' already exists" fi - # set key defaults - KEY_TYPE=${KEY_TYPE:-"RSA"} - KEY_LENGTH=${KEY_LENGTH:-"2048"} - KEY_USAGE=${KEY_USAGE:-"auth"} - KEY_EXPIRE=${KEY_EXPIRE:-"0"} - cat < = key expires in n days - w = key expires in n weeks - m = key expires in n months - y = key expires in n years -EOF - read -p "Key is valid for? ($KEY_EXPIRE) " KEY_EXPIRE; KEY_EXPIRE=${KEY_EXPIRE:-"0"} + # prompt about key expiration if not specified + keyExpire=$(get_gpg_expiration "$keyExpire") # set key parameters keyParameters=$(cat < "${MS_HOME}/ssh_host_rsa_key") - log "Private SSH host key output to file: ${MS_HOME}/ssh_host_rsa_key" + (umask 077 && \ + gpg_host --export-secret-key "$fingerprint" | \ + openpgp2ssh "$fingerprint" > "${VARLIB}/ssh_host_rsa_key") + log info "Private SSH host key output to file: ${VARLIB}/ssh_host_rsa_key" } -# gpg output key fingerprint -fingerprint_server_key() { - local ID +# extend the lifetime of a host key: +extend_key() { + local fpr=$(fingerprint_server_key) + local extendTo="$1" + + if [ -z "$fpr" ] ; then + failure "You don't appear to have a MonkeySphere host key on this server. Try 'monkeysphere-server gen-key' first." + fi + + # get the new expiration date + extendTo=$(get_gpg_expiration "$extendTo") + + gpg_host --quiet --command-fd 0 --edit-key "$fpr" </dev/null ; then - error "----- unknown user '$uname' -----" - continue - fi +y +save +EOF + ) + + # execute edit-key script + if echo "$revuidCommand" | \ + gpg_host --quiet --command-fd 0 --edit-key "0x${fingerprint}!" ; then - log "----- user: $uname -----" + # update the trustdb for the authentication keyring + gpg_authentication "--check-trustdb" - # set authorized_user_ids variable, translating ssh-style - # path variables - authorizedUserIDs=$(translate_ssh_variables "$uname" "$AUTHORIZED_USER_IDS") + show_server_key - # temporary authorized_keys file - AUTHORIZED_KEYS=$(mktemp) + echo + echo "NOTE: User ID revoked, but revocation not published." + echo "Run '$PGRM publish-key' to publish the revocation." + else + failure "Problem revoking user ID." + fi +} + +# publish server key to keyserver +publish_server_key() { + read -p "Really publish host key to $KEYSERVER? (y/N) " OK; OK=${OK:=N} + if [ ${OK/y/Y} != 'Y' ] ; then + failure "key not published." + fi + + # find the key fingerprint + fingerprint=$(fingerprint_server_key) - # process authorized_user_ids file - if [ -s "$authorizedUserIDs" ] ; then - log "processing authorized_user_ids file..." - process_authorized_user_ids "$authorizedUserIDs" + # publish host key + gpg_authentication "--keyserver $KEYSERVER --send-keys '0x${fingerprint}!'" +} + +diagnostics() { +# * check on the status and validity of the key and public certificates + local seckey + local keysfound + local curdate + local warnwindow + local warndate + local create + local expire + local uid + local fingerprint + local badhostkeys + local sshd_config + + # FIXME: what's the correct, cross-platform answer? + sshd_config=/etc/ssh/sshd_config + seckey=$(gpg_host --list-secret-keys --fingerprint --with-colons --fixed-list-mode) + keysfound=$(echo "$seckey" | grep -c ^sec:) + curdate=$(date +%s) + # warn when anything is 2 months away from expiration + warnwindow='2 months' + warndate=$(date +%s -d "$warnwindow") + + echo "Checking host GPG key..." + if (( "$keysfound" < 1 )); then + echo "! No host key found." + echo " - Recommendation: run 'monkeysphere-server gen-key'" + elif (( "$keysfound" > 1 )); then + echo "! More than one host key found?" + # FIXME: recommend a way to resolve this + else + create=$(echo "$seckey" | grep ^sec: | cut -f6 -d:) + expire=$(echo "$seckey" | grep ^sec: | cut -f7 -d:) + fingerprint=$(echo "$seckey" | grep ^fpr: | head -n1 | cut -f10 -d:) + # check for key expiration: + if [ "$expire" ]; then + if (( "$expire" < "$curdate" )); then + echo "! Host key is expired." + echo " - Recommendation: extend lifetime of key with 'monkeysphere-server extend-key'" + elif (( "$expire" < "$warndate" )); then + echo "! Host key expires in less than $warnwindow:" $(date -d "$(( $expire - $curdate )) seconds" +%F) + echo " - Recommendation: extend lifetime of key with 'monkeysphere-server extend-key'" fi + fi + + # and weirdnesses: + if [ "$create" ] && (( "$create" > "$curdate" )); then + echo "! Host key was created in the future(?!). Is your clock correct?" + echo " - Recommendation: Check clock ($(date +%F_%T)); use NTP?" + fi - # add user-controlled authorized_keys file path if specified - if [ "$USER_CONTROLLED_AUTHORIZED_KEYS" != '-' ] ; then - userAuthorizedKeys=$(translate_ssh_variables "$uname" "$USER_CONTROLLED_AUTHORIZED_KEYS") - if [ -s "$userAuthorizedKeys" ] ; then - log -n "adding user's authorized_keys file... " - cat "$userAuthorizedKeys" >> "$AUTHORIZED_KEYS" - loge "done." + # check for UserID expiration: + echo "$seckey" | grep ^uid: | cut -d: -f6,7,10 | \ + while IFS=: read create expire uid ; do + # FIXME: should we be doing any checking on the form + # of the User ID? Should we be unmangling it somehow? + + if [ "$create" ] && (( "$create" > "$curdate" )); then + echo "! User ID '$uid' was created in the future(?!). Is your clock correct?" + echo " - Recommendation: Check clock ($(date +%F_%T)); use NTP?" + fi + if [ "$expire" ] ; then + if (( "$expire" < "$curdate" )); then + echo "! User ID '$uid' is expired." + # FIXME: recommend a way to resolve this + elif (( "$expire" < "$warndate" )); then + echo "! User ID '$uid' expires in less than $warnwindow:" $(date -d "$(( $expire - $curdate )) seconds" +%F) + # FIXME: recommend a way to resolve this fi fi + done + +# FIXME: verify that the host key is properly published to the +# keyservers (do this with the non-privileged user) + +# FIXME: check that there are valid, non-expired certifying signatures +# attached to the host key after fetching from the public keyserver +# (do this with the non-privileged user as well) + +# FIXME: propose adding a revoker to the host key if none exist (do we +# have a way to do that after key generation?) + + # Ensure that the ssh_host_rsa_key file is present and non-empty: + echo + echo "Checking host SSH key..." + if [ ! -s "${VARLIB}/ssh_host_rsa_key" ] ; then + echo "! The host key as prepared for SSH (${VARLIB}/ssh_host_rsa_key) is missing or empty." + else + if [ $(stat -c '%a' "${VARLIB}/ssh_host_rsa_key") != 600 ] ; then + echo "! Permissions seem wrong for ${VARLIB}/ssh_host_rsa_key -- should be 0600." + fi + + # propose changes needed for sshd_config (if any) + if ! grep -q "^HostKey[[:space:]]\+${VARLIB}/ssh_host_rsa_key$" "$sshd_config"; then + echo "! $sshd_config does not point to the monkeysphere host key (${VARLIB}/ssh_host_rsa_key)." + echo " - Recommendation: add a line to $sshd_config: 'HostKey ${VARLIB}/ssh_host_rsa_key'" + fi + if badhostkeys=$(grep -i '^HostKey' "$sshd_config" | grep -q -v "^HostKey[[:space:]]\+${VARLIB}/ssh_host_rsa_key$") ; then + echo "! $sshd_config refers to some non-monkeysphere host keys:" + echo "$badhostkeys" + echo " - Recommendation: remove the above HostKey lines from $sshd_config" + fi + fi + fi - # if the resulting authorized_keys file is not empty - if [ -s "$AUTHORIZED_KEYS" ] ; then - # openssh appears to check the contents of the - # authorized_keys file as the user in question, so the - # file must be readable by that user at least. - # FIXME: is there a better way to do this? - chgrp $(getent passwd "$uname" | cut -f4 -d:) "$AUTHORIZED_KEYS" - chmod g+r "$AUTHORIZED_KEYS" +# FIXME: look at the ownership/privileges of the various keyrings, +# directories housing them, etc (what should those values be? can +# we make them as minimal as possible?) - # move the temp authorized_keys file into place - mv -f "$AUTHORIZED_KEYS" "${CACHE}/authorized_keys/${uname}" +# FIXME: look to see that the ownertrust rules are set properly on the +# authentication keyring - log "authorized_keys file updated." +# FIXME: make sure that at least one identity certifier exists - # else destroy it - else - rm -f "$AUTHORIZED_KEYS" - fi - done + echo + echo "Checking for MonkeySphere-enabled public-key authentication for users ..." + # Ensure that User ID authentication is enabled: + if ! grep -q "^AuthorizedKeysFile[[:space:]]\+${VARLIB}/authorized_keys/%u$" "$sshd_config"; then + echo "! $sshd_config does not point to monkeysphere authorized keys." + echo " - Recommendation: add a line to $sshd_config: 'AuthorizedKeysFile ${VARLIB}/authorized_keys/%u'" + fi + if badauthorizedkeys=$(grep -i '^AuthorizedKeysFile' "$sshd_config" | grep -q -v "^AuthorizedKeysFile[[:space:]]\+${VARLIB}/authorized_keys/%u$") ; then + echo "! $sshd_config refers to non-monkeysphere authorized_keys files:" + echo "$badauthorizedkeys" + echo " - Recommendation: remove the above AuthorizedKeysFile lines from $sshd_config" + fi +} + +# retrieve key from web of trust, import it into the host keyring, and +# ltsign the key in the host keyring so that it may certify other keys +add_certifier() { + local domain + local trust + local depth + local keyID + local fingerprint + local ltsignCommand + local trustval + + # set default values for trust depth and domain + domain= + trust=full + depth=1 + + # get options + TEMP=$(getopt -o n:t:d: -l domain:,trust:,depth: -n "$PGRM" -- "$@") + + if [ $? != 0 ] ; then + exit 1 + fi + + # Note the quotes around `$TEMP': they are essential! + eval set -- "$TEMP" + + while true ; do + case "$1" in + -n|--domain) + domain="$2" + shift 2 + ;; + -t|--trust) + trust="$2" + shift 2 + ;; + -d|--depth) + depth="$2" + shift 2 + ;; + --) + shift + ;; + *) + break + ;; + esac + done + + keyID="$1" + if [ -z "$keyID" ] ; then + failure "You must specify the key ID of a key to add." + fi + export keyID + + # get the key from the key server + gpg_authentication "--keyserver $KEYSERVER --recv-key '0x${keyID}!'" + + # get the full fingerprint of a key ID + fingerprint=$(gpg_authentication "--list-key --with-colons --with-fingerprint 0x${keyID}!" | \ + grep '^fpr:' | grep "$keyID" | cut -d: -f10) + + if [ -z "$fingerprint" ] ; then + failure "Key '$keyID' not found." + fi + + echo + echo "key found:" + gpg_authentication "--fingerprint 0x${fingerprint}!" + + echo "Are you sure you want to add the above key as a" + read -p "certifier of users on this system? (y/N) " OK; OK=${OK:-N} + if [ "${OK/y/Y}" != 'Y' ] ; then + failure "Identity certifier not added." + fi + + # export the key to the host keyring + gpg_authentication "--export 0x${fingerprint}!" | gpg_host --import + + if [ "$trust" == marginal ]; then + trustval=1 + elif [ "$trust" == full ]; then + trustval=2 + else + failure "Trust value requested ('$trust') was unclear (only 'marginal' or 'full' are supported)." + fi + + # ltsign command + # NOTE: *all* user IDs will be ltsigned + ltsignCommand=$(cat <