#!/bin/sh
#
# ipset Start and stop ipset firewall sets
#
# config: /etc/sysconfig/ipset-config
IPSET_BIN=/usr/sbin/ipset
IPSET_CONFIG=/etc/sysconfig/ipset-config
IPSET_DATA_COMPAT=/etc/sysconfig/ipset
IPSET_DATA_COMPAT_BACKUP=${IPSET_DATA_COMPAT}.save
IPSET_DATA_DIR=/etc/sysconfig/ipset.d
IPSET_DATA_DIR_BACKUP=${IPSET_DATA_DIR}.save
IPSET_DATA_SAVED_FLAG=${IPSET_DATA_DIR}/.saved
IPSET_LOCK=/run/ipset.lock
IPSET_RUN=/run/ipset.run
CLEAN_FILES=""
trap "rm -rf \${CLEAN_FILES}" EXIT
info() {
echo "ipset: ${*}" >&2
}
warn() {
echo "<4>ipset: ${*}" >&2
}
err() {
echo "<3>ipset: ${*}" >&2
}
[ -x ${IPSET_BIN} ] || { err "Cannot execute ${IPSET_BIN}"; exit 1; }
# Source ipset configuration
# shellcheck source=ipset-config
[ -f ${IPSET_CONFIG} ] && . ${IPSET_CONFIG}
set -f
lock() {
CLEAN_FILES="${CLEAN_FILES} ${IPSET_LOCK}"
until mkdir ${IPSET_LOCK} 2>/dev/null; do :; done
}
save() {
fail=0
# Make backups of existing configuration first, if any
[ -d ${IPSET_DATA_DIR} ] && mv -Tf ${IPSET_DATA_DIR} ${IPSET_DATA_DIR_BACKUP}
[ -f ${IPSET_DATA_COMPAT} ] && mv -Tf ${IPSET_DATA_COMPAT} ${IPSET_DATA_COMPAT_BACKUP}
rm -f ${IPSET_DATA_SAVED_FLAG}
# Save each set in a separate file
mkdir -p ${IPSET_DATA_DIR}
chmod 0700 ${IPSET_DATA_DIR}
IFS="
"
for set in $(${IPSET_BIN} list -n -t); do
# Empty name allowed, use ".set" as suffix. 'ipset save' doesn't
# quote set names with spaces: if we have a space in the name,
# work around this by quoting it ourselves in the output.
# shellcheck disable=SC2003 # No POSIX equivalent to expr index
if expr index "${set}" " " >/dev/null; then
:> "${IPSET_DATA_DIR}/${set}.set"
for line in $(${IPSET_BIN} save "${set}"); do
create=0
echo "${line}" | grep -q "^create " && create=1
if [ $create -eq 1 ]; then
line=${line#create *}
else
line=${line#add *}
fi
line=${line#${set} *}
set="$(echo "${set}" | sed 's/"/\\"/g')"
if [ $create -eq 1 ]; then
echo "create \"${set}\" ${line}" >> "${IPSET_DATA_DIR}/${set}.set"
else
echo "add \"${set}\" ${line}" >> "${IPSET_DATA_DIR}/${set}.set"
fi
done
else
${IPSET_BIN} save "${set}" > "${IPSET_DATA_DIR}/${set}.set" || fail=1
fi
[ -f "${IPSET_DATA_DIR}/${set}.set" ] && chmod 600 "${IPSET_DATA_DIR}/${set}.set"
[ $fail -eq 1 ] && err "Cannot save set ${set}" && unset IFS && return 1
done
touch ${IPSET_DATA_SAVED_FLAG} || { unset IFS; return 1; }
unset IFS
# Done: remove backups
rm -rf ${IPSET_DATA_DIR_BACKUP}
rm -rf ${IPSET_DATA_COMPAT_BACKUP}
return 0
}
# Generate a grep regexp matching abbreviated command forms. E.g., for create:
# \(c\|cr\|cre\|crea\|creat\|create\)
cmd_short_expr() {
out=
cmd_len=1
while [ "${cmd_len}" -le "${#1}" ]; do
[ -z "${out}" ] && out='\(' || out="${out}"'\|'
# shellcheck disable=SC2003 # No POSIX equivalent to expr substr
out="${out}$(expr substr "${1}" 1 "${cmd_len}")"
cmd_len=$((cmd_len + 1))
done
echo "${out}"'\)'
}
ipset_restore() {
file="${1}"
retfile="$(mktemp -q /tmp/ipset.XXXXXX)"
CLEAN_FILES="${CLEAN_FILES} ${retfile}"
# If restore fails due to invalid lines, remove them and retry
while ! restore_err="$( (${IPSET_BIN} -f "${file}" -! restore 2>&1; echo $? >"${retfile}") | head -n1; exit "$(cat "${retfile}")" )"; do
warn "${restore_err}"
case ${restore_err#*: } in
"No command specified"*)
line="$(grep -m1 -n "^${restore_err##* }" "${file}")"
line="${line%:*}"
;;
"Missing second mandatory argument to command "*)
cmd="${restore_err##* }"
cmd_expr="$(cmd_short_expr "${cmd}")"
line="$(grep -n '^'"${cmd_expr}" "${file}" | grep -m1 -v '^[0-9]\+\:'"${cmd_expr}"'[[:blank:]]\+[^[:blank:]]\+[[:blank:]]\+[^[:blank:]]\+')"
line="${line%:*}"
;;
"Missing mandatory argument to command "*)
cmd="${restore_err##* }"
cmd_expr="$(cmd_short_expr "${cmd}")"
line="$(grep -n '^'"${cmd_expr}" "${file}" | grep -m1 -v '^[0-9]\+\:'"${cmd_expr}"'[[:blank:]]\+[^[:blank:]]\+')"
line="${line%:*}"
;;
"Command "*"is invalid in restore mode"*)
restore_err_cmd="${restore_err#*: }"
restore_err_cmd="${restore_err_cmd#*\`}"
restore_err_cmd="${restore_err_cmd%%\'*}"
cmd="${restore_err_cmd##* }"
cmd_expr="$(cmd_short_expr "${cmd}")"
line="$(grep -m1 -ne '^'"${cmd_expr}"'[[:blank:]]\+' -e '^'"${restore_err_cmd}"'$' "${file}")"
line="${line%:*}"
;;
"Error in line "*)
line="${restore_err%: *}"
line="${line##* }"
;;
*)
rm "${retfile}"
CLEAN_FILES="${CLEAN_FILES%* ${retfile}}"
return 1
;;
esac
[ -z "${line}" ] && return 1
warn "Skipped invalid entry: $(sed "${line}q;d" "${file}")"
sed -i -e "${line}d" "${file}"
[ -s "${file}" ] || return 1
done
rm "${retfile}"
CLEAN_FILES="${CLEAN_FILES%* ${retfile}}"
}
load() {
if [ -f ${IPSET_DATA_SAVED_FLAG} ]; then
# If we have a cleanly saved directory with all sets, we can
# delete any left-overs and use it
rm -rf ${IPSET_DATA_DIR_BACKUP}
rm -f ${IPSET_DATA_COMPAT_BACKUP}
else
# If sets weren't cleanly saved, restore from backups
[ -d ${IPSET_DATA_DIR_BACKUP} ] && rm -rf ${IPSET_DATA_DIR} && mv -Tf ${IPSET_DATA_DIR_BACKUP} ${IPSET_DATA_DIR}
[ -f ${IPSET_DATA_COMPAT_BACKUP} ] && rm -f ${IPSET_DATA_COMPAT} && mv -Tf ${IPSET_DATA_COMPAT_BACKUP} ${IPSET_DATA_COMPAT}
fi
if [ ! -d ${IPSET_DATA_DIR} ] && [ ! -f ${IPSET_DATA_COMPAT} ]; then
info "No existing configuration available, none loaded"
touch ${IPSET_RUN}
return
fi
# Merge all sets into temporary file
merged="$(mktemp -q /tmp/ipset.XXXXXX)"
CLEAN_FILES="${CLEAN_FILES} ${merged}"
chmod 600 "${merged}"
set +f
if [ -d ${IPSET_DATA_DIR} ]; then
# Copy create commands from each saved set first, then the rest:
# list:set entries depend on other sets, so make sure they all
# get created first
for f in "${IPSET_DATA_DIR}"/*; do
[ "${f}" = "${IPSET_DATA_DIR}/*" ] && break
[ -f "${f}" ] || continue
grep '^c' "${f}" >> "${merged}"
done
for f in "${IPSET_DATA_DIR}"/*; do
[ "${f}" = "${IPSET_DATA_DIR}/*" ] && break
[ -f "${f}" ] || continue
grep -v '^c' "${f}" >> "${merged}"
done
fi
set -f
[ -f ${IPSET_DATA_COMPAT} ] && cat ${IPSET_DATA_COMPAT} >> "${merged}"
# Drop sets that aren't in saved data, mark conflicts with existing sets
conflicts=""
IFS="
"
for set in $(${IPSET_BIN} list -n -t); do
grep -q "^create ${set} " "${merged}" && conflicts="${conflicts}|${set}" && continue
# We can't destroy the set if it's in use, flush it instead
if ! ${IPSET_BIN} destroy "${set}" 2>/dev/null; then
${IPSET_BIN} flush "${set}"
fi
done
unset IFS
conflicts="${conflicts#|*}"
# Common case: if we have no conflicts, just restore in one shot
if [ -z "${conflicts}" ]; then
if ! ipset_restore "${merged}"; then
err "Failed to restore configured sets"
exit 1
fi
rm "${merged}"
CLEAN_FILES="${CLEAN_FILES%* ${merged}}"
touch ${IPSET_RUN}
return
fi
# Find a salt for md5sum that makes names of saved sets unique
salt=0
while true; do
unique=1
IFS="
"
for set in $(${IPSET_BIN} list -n -t); do
if grep -q "^create $(echo "${salt}${set}" | md5sum | head -c31) " "${merged}"; then
unique=0
break
fi
done
unset IFS
[ ${unique} -eq 1 ] && break
salt=$((salt + 1))
done
# Add sets, mangling names for conflicting sets
mangled="$(mktemp -q /tmp/ipset.XXXXXX)"
CLEAN_FILES="${CLEAN_FILES} ${mangled}"
chmod 600 "${mangled}"
awk '/^(add|create) ('"${conflicts}"')/ { printf "%s ",$1; system("echo '${salt}'" $2 " | md5sum | head -c31"); $1=""; $2=""; print; next} {print}' "${merged}" > "${mangled}"
if ! ipset_restore "${mangled}"; then
err "Failed to restore configured sets"
exit 1
fi
rm "${mangled}"
CLEAN_FILES="${CLEAN_FILES%* ${mangled}}"
# Swap and delete old sets
IFS='|'
for set in ${conflicts}; do
mangled="$(echo "${salt}${set}" | md5sum | head -c31)"
if ! ${IPSET_BIN} swap "${set}" "${mangled}" 2>/dev/null; then
# This fails if set types are different: try to destroy
# existing set
if ! ${IPSET_BIN} destroy "${set}" 2>/dev/null; then
# Conflicting set is in use, we can only warn
# and flush the existing set
err "Cannot load set \"${set}\", set with same name and conflicting type in use"
${IPSET_BIN} flush "${set}"
${IPSET_BIN} destroy "${mangled}"
else
${IPSET_BIN} rename "${mangled}" "${set}"
fi
else
${IPSET_BIN} destroy "${mangled}"
fi
done
unset IFS
rm "${merged}"
CLEAN_FILES="${CLEAN_FILES%* ${merged}}"
touch ${IPSET_RUN}
}
cleanup() {
${IPSET_BIN} flush || err "Failed to flush sets"
# Try to destroy all sets at once. This will fail if some are in use,
# destroy all the other ones in that case
${IPSET_BIN} destroy 2>/dev/null && return
IFS="
"
for set in $(${IPSET_BIN} list -n -t); do
if ! ${IPSET_BIN} destroy "${set}"; then
err "Failed to destroy set ${set}"
fi
done
unset IFS
}
stop() {
[ -f ${IPSET_RUN} ] || { info "Not running"; return 0; }
[ "${IPSET_SAVE_ON_STOP}" = "yes" ] && { save || err "Failed to save sets"; }
# Nothing to stop if the ip_set module is not loaded
lsmod | grep -q "^ip_set " || { info "Not running"; rm ${IPSET_RUN}; return 0; }
# If the xt_set module is in use, then iptables is using ipset, so
# refuse to stop the service
if mod="$(lsmod | grep ^xt_set)"; then
if [ "$(echo "${mod}" | tr -s ' ' | cut -d' ' -f3)" != "0" ]; then
err "Current iptables configuration requires ipset" && return 1
fi
fi
cleanup
rm ${IPSET_RUN}
return 0
}
lock
case "$1" in
start)
load
;;
stop)
stop
;;
reload)
cleanup
load
;;
save)
save
;;
*)
info "Usage: $0 {start|stop|reload|save}"
exit 1
esac
exit $?