summaryrefslogtreecommitdiffstats
path: root/iptables/iptables-apply
diff options
context:
space:
mode:
Diffstat (limited to 'iptables/iptables-apply')
-rwxr-xr-xiptables/iptables-apply302
1 files changed, 211 insertions, 91 deletions
diff --git a/iptables/iptables-apply b/iptables/iptables-apply
index 819ca4a4..4683b1b4 100755
--- a/iptables/iptables-apply
+++ b/iptables/iptables-apply
@@ -1,174 +1,294 @@
#!/bin/bash
-#
# iptables-apply -- a safer way to update iptables remotely
#
-# Copyright © Martin F. Krafft <madduck@madduck.net>
+# Usage:
+# iptables-apply [-hV] [-t timeout] [-w savefile] {[rulesfile]|-c [runcmd]}
+#
+# Versions:
+# * 1.0 Copyright 2006 Martin F. Krafft <madduck@madduck.net>
+# Original version
+# * 1.1 Copyright 2010 GW <gw.2010@tnode.com or http://gw.tnode.com/>
+# Added parameter -c (run command)
+# Added parameter -w (save successfully applied rules to file)
+# Major code cleanup
+#
# Released under the terms of the Artistic Licence 2.0
#
set -eu
-PROGNAME="${0##*/}";
-VERSION=1.0
+PROGNAME="${0##*/}"
+VERSION=1.1
+
+
+### Default settings
+
+DEF_TIMEOUT=10
+
+MODE=0 # apply rulesfile mode
+# MODE=1 # run command mode
+
+case "$PROGNAME" in
+ (*6*)
+ SAVE=ip6tables-save
+ RESTORE=ip6tables-restore
+ DEF_RULESFILE="/etc/network/ip6tables.up.rules"
+ DEF_SAVEFILE="$DEF_RULESFILE"
+ DEF_RUNCMD="/etc/network/ip6tables.up.run"
+ ;;
+ (*)
+ SAVE=iptables-save
+ RESTORE=iptables-restore
+ DEF_RULESFILE="/etc/network/iptables.up.rules"
+ DEF_SAVEFILE="$DEF_RULESFILE"
+ DEF_RUNCMD="/etc/network/iptables.up.run"
+ ;;
+esac
+
-TIMEOUT=10
+### Functions
-function blurb()
-{
- cat <<-_eof
+function blurb() {
+ cat <<-__EOF__
$PROGNAME $VERSION -- a safer way to update iptables remotely
- _eof
+ __EOF__
}
-function copyright()
-{
- cat <<-_eof
- $PROGNAME is C Martin F. Krafft <madduck@madduck.net>.
+function copyright() {
+ cat <<-__EOF__
+ $PROGNAME has been published under the terms of the Artistic Licence 2.0.
- The program has been published under the terms of the Artistic Licence 2.0
- _eof
+ Original version - Copyright 2006 Martin F. Krafft <madduck@madduck.net>.
+ Version 1.1 - Copyright 2010 GW <gw.2010@tnode.com or http://gw.tnode.com/>.
+ __EOF__
}
-function about()
-{
+function about() {
blurb
echo
copyright
}
-function usage()
-{
- cat <<-_eof
- Usage: $PROGNAME [options] ruleset
+function usage() {
+ blurb
+ echo
+ cat <<-__EOF__
+ Usage:
+ $PROGNAME [-hV] [-t timeout] [-w savefile] {[rulesfile]|-c [runcmd]}
+
+ The script will try to apply a new rulesfile (as output by iptables-save,
+ read by iptables-restore) or run a command to configure iptables and then
+ prompt the user whether the changes are okay. If the new iptables rules cut
+ the existing connection, the user will not be able to answer affirmatively.
+ In this case, the script rolls back to the previous working iptables rules
+ after the timeout expires.
+
+ Successfully applied rules can also be written to savefile and later used
+ to roll back to this state. This can be used to implement a store last good
+ configuration mechanism when experimenting with an iptables setup script:
+ $PROGNAME -w $DEF_SAVEFILE -c $DEF_RUNCMD
- The script will try to apply a new ruleset (as output by iptables-save/read
- by iptables-restore) to iptables, then prompt the user whether the changes
- are okay. If the new ruleset cut the existing connection, the user will not
- be able to answer affirmatively. In this case, the script rolls back to the
- previous ruleset.
+ When called as ip6tables-apply, the script will use ip6tables-save/-restore
+ and IPv6 default values instead. Default value for rulesfile is
+ '$DEF_RULESFILE'.
+
+ Options:
+
+ -t seconds, --timeout seconds
+ Specify the timeout in seconds (default: $DEF_TIMEOUT).
+ -w savefile, --write savefile
+ Specify the savefile where successfully applied rules will be written to
+ (default if empty string is given: $DEF_SAVEFILE).
+ -c runcmd, --command runcmd
+ Run command runcmd to configure iptables instead of applying a rulesfile
+ (default: $DEF_RUNCMD).
+ -h, --help
+ Display this help text.
+ -V, --version
+ Display version information.
+
+ __EOF__
+}
- The following options may be specified, using standard conventions:
+function checkcommands() {
+ for cmd in "${COMMANDS[@]}"; do
+ if ! command -v "$cmd" >/dev/null; then
+ echo "Error: needed command not found: $cmd" >&2
+ exit 127
+ fi
+ done
+}
- -t | --timeout Specify the timeout in seconds (default: $TIMEOUT)
- -V | --version Display version information
- -h | --help Display this help text
- _eof
+function revertrules() {
+ echo -n "Reverting to old iptables rules... "
+ "$RESTORE" <"$TMPFILE"
+ echo "done."
}
-SHORTOPTS="t:Vh";
-LONGOPTS="timeout:,version,help";
+
+### Parsing and checking parameters
+
+TIMEOUT="$DEF_TIMEOUT"
+SAVEFILE=""
+
+SHORTOPTS="t:w:chV";
+LONGOPTS="timeout:,write:,command,help,version";
OPTS=$(getopt -s bash -o "$SHORTOPTS" -l "$LONGOPTS" -n "$PROGNAME" -- "$@") || exit $?
for opt in $OPTS; do
case "$opt" in
- (-*) unset OPT_STATE;;
+ (-*)
+ unset OPT_STATE
+ ;;
(*)
case "${OPT_STATE:-}" in
- (SET_TIMEOUT)
- eval TIMEOUT=$opt
- case "$TIMEOUT" in
- ([0-9]*) :;;
- (*)
- echo "E: non-numeric timeout value." >&2
- exit 1
- ;;
- esac
+ (SET_TIMEOUT) eval TIMEOUT=$opt;;
+ (SET_SAVEFILE)
+ eval SAVEFILE=$opt
+ [ -z "$SAVEFILE" ] && SAVEFILE="$DEF_SAVEFILE"
;;
esac
;;
esac
case "$opt" in
+ (-t|--timeout) OPT_STATE="SET_TIMEOUT";;
+ (-w|--write) OPT_STATE="SET_SAVEFILE";;
+ (-c|--command) MODE=1;;
(-h|--help) usage >&2; exit 0;;
(-V|--version) about >&2; exit 0;;
- (-t|--timeout) OPT_STATE=SET_TIMEOUT;;
(--) break;;
esac
shift
done
-case "$PROGNAME" in
- (*6*)
- SAVE=ip6tables-save
- RESTORE=ip6tables-restore
- DEFAULT_FILE=/etc/network/ip6tables
- ;;
- (*)
- SAVE=iptables-save
- RESTORE=iptables-restore
- DEFAULT_FILE=/etc/network/iptables
- ;;
-esac
-
-FILE="${1:-$DEFAULT_FILE}";
-
-if [[ -z "$FILE" ]]; then
- echo "E: missing file argument." >&2
+# Validate parameters
+if [ "$TIMEOUT" -ge 0 ] 2>/dev/null; then
+ TIMEOUT=$(($TIMEOUT))
+else
+ echo "Error: timeout must be a positive number" >&2
exit 1
fi
-if [[ ! -r "$FILE" ]]; then
- echo "E: cannot read $FILE" >&2
- exit 2
+if [ -n "$SAVEFILE" -a -e "$SAVEFILE" -a ! -w "$SAVEFILE" ]; then
+ echo "Error: savefile not writable: $SAVEFILE" >&2
+ exit 8
fi
-COMMANDS=(tempfile "$SAVE" "$RESTORE")
+case "$MODE" in
+ (1)
+ # Treat parameter as runcmd (run command mode)
+ RUNCMD="${1:-$DEF_RUNCMD}"
+ if [ ! -x "$RUNCMD" ]; then
+ echo "Error: runcmd not executable: $RUNCMD" >&2
+ exit 6
+ fi
+
+ # Needed commands
+ COMMANDS=(mktemp "$SAVE" "$RESTORE" "$RUNCMD")
+ checkcommands
+ ;;
+ (*)
+ # Treat parameter as rulesfile (apply rulesfile mode)
+ RULESFILE="${1:-$DEF_RULESFILE}";
+ if [ ! -r "$RULESFILE" ]; then
+ echo "Error: rulesfile not readable: $RULESFILE" >&2
+ exit 2
+ fi
+
+ # Needed commands
+ COMMANDS=(mktemp "$SAVE" "$RESTORE")
+ checkcommands
+ ;;
+esac
-for cmd in "${COMMANDS[@]}"; do
- if ! command -v $cmd >/dev/null; then
- echo "E: command not found: $cmd" >&2
- exit 127
- fi
-done
-umask 0700
+### Begin work
-TMPFILE=$(tempfile -p iptap)
+# Store old iptables rules to temporary file
+TMPFILE=`mktemp /tmp/$PROGNAME-XXXXXXXX`
trap "rm -f $TMPFILE" EXIT HUP INT QUIT ILL TRAP ABRT BUS \
FPE USR1 SEGV USR2 PIPE ALRM TERM
if ! "$SAVE" >"$TMPFILE"; then
+ # An error occured
if ! grep -q ipt /proc/modules 2>/dev/null; then
- echo "E: iptables support lacking from the kernel." >&2
+ echo "Error: iptables support lacking from the kernel" >&2
exit 3
else
- echo "E: unknown error saving current iptables ruleset." >&2
+ echo "Error: unknown error saving old iptables rules: $TMPFILE" >&2
exit 4
fi
fi
+# Legacy to stop the fail2ban daemon if present
[ -x /etc/init.d/fail2ban ] && /etc/init.d/fail2ban stop
-echo -n "Applying new ruleset... "
-if ! "$RESTORE" <"$FILE"; then
- echo "failed."
- echo "E: unknown error applying new iptables ruleset." >&2
- exit 5
-else
- echo "done."
-fi
+# Configure iptables
+case "$MODE" in
+ (1)
+ # Run command in background and kill it if it times out
+ echo -n "Running command '$RUNCMD'... "
+ "$RUNCMD" &
+ CMD_PID=$!
+ ( sleep "$TIMEOUT"; kill "$CMD_PID" 2>/dev/null; exit 0 ) &
+ CMDTIMEOUT_PID=$!
+ if ! wait "$CMD_PID"; then
+ echo "failed."
+ echo "Error: unknown error running command: $RUNCMD" >&2
+ revertrules
+ exit 7
+ else
+ echo "done."
+ fi
+ ;;
+ (*)
+ # Apply iptables rulesfile
+ echo -n "Applying new iptables rules from '$RULESFILE'... "
+ if ! "$RESTORE" <"$RULESFILE"; then
+ echo "failed."
+ echo "Error: unknown error applying new iptables rules: $RULESFILE" >&2
+ revertrules
+ exit 5
+ else
+ echo "done."
+ fi
+ ;;
+esac
+# Prompt user for confirmation
echo -n "Can you establish NEW connections to the machine? (y/N) "
-read -n1 -t "${TIMEOUT:-15}" ret 2>&1 || :
+read -n1 -t "$TIMEOUT" ret 2>&1 || :
case "${ret:-}" in
(y*|Y*)
+ # Success
echo
+
+ if [ ! -z "$SAVEFILE" ]; then
+ # Write successfully applied rules to the savefile
+ echo "Writing successfully applied rules to '$SAVEFILE'..."
+ if ! "$SAVE" >"$SAVEFILE"; then
+ echo "Error: unknown error writing successfully applied rules: $SAVEFILE" >&2
+ exit 9
+ fi
+ fi
+
echo "... then my job is done. See you next time."
;;
(*)
- if [[ -z "${ret:-}" ]]; then
- echo "apparently not..."
+ # Failed
+ echo
+ if [ -z "${ret:-}" ]; then
+ echo "Timeout! Something happened (or did not). Better play it safe..."
else
- echo
+ echo "No affirmative response! Better play it safe..."
fi
- echo "Timeout. Something happened (or did not). Better play it safe..."
- echo -n "Reverting to old ruleset... "
- "$RESTORE" <"$TMPFILE";
- echo "done."
+ revertrules
exit 255
;;
esac
+# Legacy to start the fail2ban daemon again
[ -x /etc/init.d/fail2ban ] && /etc/init.d/fail2ban start
exit 0