#!/bin/sh
#
-# Marta Carbone
-# Copyright (C) 2009 UniPi
+# Marta Carbone, Luigi Rizzo
+# Copyright (C) 2009 Universita` di Pisa
# $Id$
#
-# This script is the backend to be used with
-# the vsys system.
-# It allows to configure dummynet pipes and queues.
+# This script the vsys backend used to configure emulation.
# In detail it:
-# - read the user's input from the input pipe
-# - validate the input
-# - set the firewall
-# - put results on the output vsys pipe
+# - reads the user's input from the vsys input pipe
+# - validates the input
+# - configures the firewall
+# - writes results on the output vsys pipe
#
-# This script expect to read from the input vsys
-# pipe a line formatted as follow:
-# ${PORT} ${TIMEOUT} <dummynet parameters>
-# the timeout value is expressed as:
-# week, day, month or anything else accepted by the date command
-
-# save the slicename
-SLICE=$1
-
-LOG_FILE=/tmp/netconfig.log
+# Configurable variables are at the beginning (only HOOK so far)
+
+# If HOOK is set, ${HOOK} is called before configuring a rule.
+# A sample hook can be found in the ipfwroot.rpm package,
+# it can be used to collect statistical information on dummynet usage.
+# To configure a hook, set the HOOK variable as follow:
+# HOOK=/tmp/sample_hook
+
+#--- You should not touch anything below this line. ----
+# For documentation see ARCHITECTURE near the end of the file.
+
+#--- global variables ---
+VERBOSE=0 # set to !0 to enable debug messages
+TEST=0 # set to 1 for test mode
+
+# The database and the lock file
+DBFILE=/tmp/ff
+lockfile=/var/lock/ipfw.lock
+
+# Min and max value (inclusive) for block_index
+BLOCK_MIN=1
+BLOCK_MAX=1000
+M=50 # size of per-slice block of rules
+# Min and max value (inclusive) for pipe_index
+PIPE_MIN=1
+PIPE_MAX=25000
+
+# These are the actual rule numbers used in ipfw
+IPFW_RULE_MIN=10000 # initial per-slice rule number
+IPFW_PIPE_MIN=10000 # initial pipe number
+
+# The skipto and the generic default rule
+# these values are used to initialize the firewall
+SLICE_TABLE=1 # table number used for slice ids lookup
+S=1000 # firewall rule number for the skipto rule
+D=2000 # default rule for reserved section
+
+# set slicename and slice_id
+# these are the credential of the user invoking the backend
+SLICENAME=$1
+SLICE_ID=`id -u $SLICENAME`
+[ x"$SLICE_ID" = x"" ] && echo "No sliver present." && exit
# programs
-CUT=/usr/bin/cut
+# XXX check consistency for variables {}
SED=/bin/sed
+SEDOPT=-r
+[ -x ${SED} ] || { SED=`which sed` ; SEDOPT=-E ; }
IPFW=/sbin/ipfw
-
-# set to 0 to disable debug messages
-DEBUG=0
+IPFW_CHECK="/sbin/ipfw -n"
debug() { # $1 message to be displayed
- [ x"${DEBUG}" != x"0" ] && echo $1 >>{LOG_FILE};
+ [ x"${VERBOSE}" != x"0" ] && echo "ipfw-be: $1"
}
-abort() { # $1 message to be displayed
- echo "$1"
- exit 1
+# if the first argument is -v, enable verbose mode
+set_verbose() {
+ [ x"$1" = x"-v" -o x"$2" = x"-v" ] && VERBOSE=1
+}
+
+# set test mode if -q is found
+set_test() {
+ [ x"$1" = x"-q" -o x"$2" = x"-q" ] || return
+ TEST=1
+ IPFW="/bin/echo ipfw:"
+ IPFW_CHECK="/bin/echo ipfw -n:"
}
-user_error() { # $1 message to be displayed
- echo "1 User error: $1"
+abort() { # $1 message to be displayed in case of error
+ release_lock
+ echo "ipfw-be aborting (netconfig help): $1"
exit 1
}
+# remove dangerous characters from user input
+# if present, the leading '-v/-q' will be removed
filter() { # $* variables to be filtered
- # allowed chars are: numbers, upcase and lowecase
- # chars, and the following symbols: . _ - /
- echo "$*" | ${SED} -r 's/[^0-9a-zA-Z. _\/\-]*//g'
-}
-
-# Add ipfw pipe and rules
-# We use the PORT number to configure the
-# pipe, and add rules for that port.
-# The default directory is the slicename root
-add_rules() { # $1 timeout value $2 delete
- local EXPIRE
-
- debug "Add a new rule, check for deletion flag";
- if [ ${2} -eq 1 ]; then
- #echo "Rules and pipes deleted";
- return;
- fi
+ [ x${1} = x"-v" -o x${1} = x"-q" ] && shift
+ [ x${1} = x"-v" -o x${1} = x"-q" ] && shift
+ # allowed chars are: numbers, uppercase and lowercase letters,
+ # spaces, and the following symbols: .,_-/
+ echo "$*" | ${SED} ${SEDOPT} 's/[^\t0-9a-zA-Z., _\/\{}@-]*//g'
+}
- debug "Add a new rule"
- # schedule the rule deletion
- EXPIRE=`date --date="${TIMEOUT}" +%s`
- [ x"${EXPIRE}" = x"" ] && abort "Date format $1 not valid"
-
- # move in the slice root dir
- cd /vservers/${SLICE}/root
- #echo ${CONFIG_STRING} | ${SED} -e "s/ profile \(.[^ ]\)/ profile \/vservers\/${SLICE}\/\1/g"
-
- # check syntax, if ok execute
- # add rules
- local IPFW_CHECK="${IPFW} -n "
- local ERROR=0
-
- [ $ERROR -eq 0 ] && \
- ${IPFW_CHECK} add ${RULE_N} pipe ${PIPE_N} ip from ${ME} to any src-port ${PORT} // ${EXPIRE} ${SLICE}
- let "ERROR += $?"
- [ $ERROR -eq 0 ] && \
- ${IPFW_CHECK} add ${RULE_N} pipe ${PIPE_N} ip from any to ${ME} dst-port ${PORT}
-
- let "ERROR += $?"
- [ $ERROR -eq 0 ] && \
- ${IPFW_CHECK} pipe ${PIPE_N} config ${CONFIG_STRING}
-
- if [ ! $ERROR -eq 0 ]; then
- echo "Some errors occurred not executing"
- user_error "ipfw syntax error"
- fi
-
- # add rules
- ${IPFW} add ${RULE_N} pipe ${PIPE_N} ip from ${ME} to any src-port ${PORT} // ${EXPIRE} ${SLICE}
- ${IPFW} add ${RULE_N} pipe ${PIPE_N} ip from any to ${ME} dst-port ${PORT}
-
- # config pipe
- ${IPFW} pipe ${PIPE_N} config ${CONFIG_STRING}
-}
-
-# Delete a given link
-delete_link()
-{
- ipfw delete ${RULE_N}
- ipfw pipe delete ${RULE_N}
-}
-
-# The rule we want to configure already exist.
-# Check for slice owner matching.
-modify_rule()
-{
- local RULE
-
- RULE=`ipfw list ${PORT} 2>&1 | cut -d ' ' -f 12`;
- if [ "${RULE}" = "${SLICE}" ] ; then # replace the link configuration
- debug "The rule already exist, the owner match, delete old rule"
- echo "Owner match"
- delete_link
- add_rules ${TIMEOUT} ${DELETE}
- else
- user_error "the rule already exist, ant you are not the slice owner, try later"
- fi
-}
-
-# process a single line of input
-# this line has the following format:
-# ipfw
-# pipe
-# port timeout configuration_string
-process()
-{
- local TMP; # temporary var
-
- debug "Received from the input pipe: $1"
-
- # allow netconfig ipfw show
- # allow netconfig pipe show
-
- CMD=`echo $1 | cut -d\ -f 1`
- if [ x${CMD} == x"ipfw" ]; then
- ipfw show
- return 0
- else if [ x${CMD} == x"pipe" ]; then
- ipfw pipe show
- return 0
- fi
- fi
+# remove all entries from the ipfw config, and create an empty db
+clean_db() {
+ rm -f ${DBFILE}
+ touch ${DBFILE}
+ # we would like to delete ranges of rules and pipes but this
+ # is not supported so for the time being we kill them all
+ ${IPFW} -q flush
+ ${IPFW} -q pipe flush
+ ${IPFW} -q table $SLICE_TABLE flush
+ #${IPFW} delete ${IPFW_RULE_MIN}-${IPFW_RULE_MAX}
+ #${IPFW} pipe delete ${IPFW_PIPE_MIN}-${IPFW_PIPE_MAX}
+ # since all rules are now deleted, we should initialize the firewall
+ ipfw_init
+}
- ARGS=`echo $1 | wc -w`
- if [ $ARGS -le 2 ]; then
- abort "One or more input parameter is missing"
- fi
+#
+# Add the ipfw rule/pipe and update the database.
+# The pipe-in and pipe-out config are through global variables
+# rule_in rule_out because they may be long. XXX why ?
+# Other arguments are on the command line
+#
+# the new_rule variable is set if the rule to be installed is new
+# we need to know this because we do not want to clean
+# rule counters on pipes reconfiguration
+add_rule() { # slice_id new_rule type arg ipfw_rule pipe_index timeout
+ local slice_id=$1 new_rule=$2 type=$3 arg=$4
+ local ipfw_rule=$5 pipe_index=$6 timeout=$7
+ local ipfw_pipe_in ipfw_pipe_out check_timeout
+ local p h # used to split the argument
+
+ local h_in h_out
+ # local rule_in rule_out # XXX test if this works
+ # find actual pipe numbers
+ ipfw_pipe_in=$(($IPFW_PIPE_MIN + $((2 * $(($pipe_index - 1)))) ))
+ ipfw_pipe_out=$(($ipfw_pipe_in + 1))
+ local del # used to delete incompatible configurations
+
+ # split the argument, and prepare PORTLIST (p) and ADDRLIST (h)
+ p=`echo $arg | cut -s -d "@" -f1-` # empty if no separator
+ if [ "$p" = "" ] ; then
+ p=$arg
+ else
+ p=`echo $arg | cut -d "@" -f1`
+ h=`echo $arg | cut -d "@" -f2`
+ fi
+
+ if [ "$h" = "" ] ; then
+ h_in=""
+ h_out=""
+ else
+ h_in=" src-ip ${h} "
+ h_out=" dst-ip ${h} "
+ fi
+
+ # first, call ipfw -n to check syntax, if ok move on and do the action
+ if [ x"$new_rule" != x"0" ] ; then
+ case $type in
+ SERVER|server)
+ rule_in="dst-port $p"
+ rule_out="src-port $p"
+ del=service
+ ;;
+ CLIENT|client)
+ rule_in="src-port $p"
+ rule_out="dst-port $p"
+ del=service
+ ;;
+ SERVICE|service)
+ rule_in="{ src-port $p or dst-port $p }"
+ rule_out="{ src-port $p or dst-port $p }"
+ del="cli_ser"
+ ;;
+ *)
+ abort "invalid service type $type"
+ ;;
+ esac
+
+ rule_in="pipe ${ipfw_pipe_in} in ${h_in} ${rule_in} // $type $arg $slice_id"
+ rule_out="pipe ${ipfw_pipe_out} out ${h_out} ${rule_out} // $type $arg $slice_id"
+
+ # Move into the user root directory. The profile should be located there
+ ( cd /vservers/${SLICENAME}/`pwd`/ ; ${IPFW_CHECK} add ${ipfw_rule} ${rule_in} ) > /dev/null || \
+ abort "ipfw syntax error ${rule_in}"
+ ( cd /vservers/${SLICENAME}/`pwd`/ ; ${IPFW_CHECK} add ${ipfw_rule} ${rule_out} ) > /dev/null || \
+ abort "ipfw syntax error ${rule_out}"
+ fi
+
+ # check error reporting
+ ( cd /vservers/${SLICENAME}/`pwd`/ ; ${IPFW_CHECK} pipe ${ipfw_pipe_in} config ${CONFIG_PIPE_IN} ) > /dev/null || \
+ abort "ipfw syntax error pipe_in"
+ ( cd /vservers/${SLICENAME}/`pwd`/ ; ${IPFW_CHECK} pipe ${ipfw_pipe_out} config ${CONFIG_PIPE_OUT} ) > /dev/null || \
+ abort "ipfw syntax error pipe_out"
+
+ # all good, delete and add rules if necessary
+ [ "$del" = "service" ] && do_delete 0 $slice_id service $arg
+ [ "$del" = "cli_ser" ] && do_delete 0 $slice_id client $arg
+ [ "$del" = "cli_ser" ] && do_delete 0 $slice_id server $arg
+ [ "$new_rule" != "0" ] && ${IPFW} add ${ipfw_rule} $rule_in > /dev/null
+ [ "$new_rule" != "0" ] && ${IPFW} add ${ipfw_rule} $rule_out > /dev/null
+ # config pipes
+ ( cd /vservers/${SLICENAME}/`pwd`/ ; ${IPFW} pipe ${ipfw_pipe_in} config ${CONFIG_PIPE_IN} )
+ ( cd /vservers/${SLICENAME}/`pwd`/ ; ${IPFW} pipe ${ipfw_pipe_out} config ${CONFIG_PIPE_OUT} )
+
+ # send output to the user
+ ${IPFW} show ${ipfw_rule}
+ ${IPFW} pipe ${ipfw_pipe_in} show
+ ${IPFW} pipe ${ipfw_pipe_out} show
+
+ # do not write on the database on test-only
+ [ "$TEST" = "1" ] && return
+ # add to the database
+ ( grep -iv -- "^${slice_id} ${type} ${arg} " $DBFILE; \
+ echo "${slice_id} ${type} ${arg} ${ipfw_rule} ${pipe_index} ${timeout}" ) > ${DBFILE}.tmp
+ mv ${DBFILE}.tmp ${DBFILE}
+}
- # filter input
- TMP=`echo $1 | cut -d\ -f 1`
- PORT=`filter $TMP`
- TMP=`echo $1 | cut -d\ -f 2`
- TIMEOUT=`filter $TMP`
- TMP=`echo $1 | cut -d\ -f 3`
- DELETE=`filter $TMP`
- TMP=`echo $1 | cut -d\ -f 4-`
- CONFIG_STRING=`filter $TMP`
-
- debug "PORT: $PORT"
- debug "DELETE: $DELETE"
- debug "TIMEOUT: $TIMEOUT"
- debug "configuration string: $CONFIG_STRING"
-
- # find the ip address
- ME=`/sbin/ip -o addr show | grep -v "1:\ lo" | grep "inet " | cut -d " " -f7 | cut -d "/" -f1 | head -n1`
-
- # deny port <= 1024
- [ ${PORT} -le 1024 ] && user_error "it is not allowed to modify the port range [0-1024]"
-
- # start to configure pipes and rules
- PIPE_N=${PORT}
- RULE_N=${PORT}
-
- # check if the link is already configured
- ipfw list ${PORT} 2>&1
-
- if [ x"$?" != x"0" ]; then # new rule, add and set owner/timeout
- add_rules ${TIMEOUT} ${DELETE}
- else # the rule already exist, check owner
- modify_rule
- fi
+#
+# Delete a given configuration
+# if block_deletion !0 free block resources (if necessary)
+# otherwise leave the block allocated in case
+# we are adding the first rule
+do_delete() { # block_deletion slice_id type arg
+ local ipfw_pipe_in ipfw_pipe_out pipe_index ipfw_rule
+ local block_deletion=$1 slice_id=$2 type=$3 arg=$4
+
+ [ "${type}" = "BLOCK" ] && abort "A BLOCK can not be deleted"
+ [ "${arg}" = "" ] && abort "Missing args on 'delete', expected on of {CLIENT|SERVER|SERVICE} arg"
+ set `find_rule $slice_id $type $arg`
+ ipfw_rule=$1; pipe_index=$2
+ [ "$ipfw_rule" = "0" ] && return # no rules found
+
+ # find actual pipe numbers XXX do as function
+ ipfw_pipe_in=$(($IPFW_PIPE_MIN + $((2 * $(($pipe_index - 1)))) ))
+ ipfw_pipe_out=$(($ipfw_pipe_in + 1))
+
+ echo "removing configuration ${slice_id} ${type} ${arg}"
+ [ "$TEST" = "1" ] && return 0
+ $IPFW delete ${ipfw_rule}
+ $IPFW pipe delete ${ipfw_pipe_in}
+ $IPFW pipe delete ${ipfw_pipe_out}
+ # remove from the database (case insensitive)
+ grep -iv -- "^${slice_id} ${type} ${arg} " $DBFILE > ${DBFILE}.tmp
+ mv ${DBFILE}.tmp ${DBFILE}
+
+ # if there are no more rules for the user
+ # remove the table entry from ipfw and from the db
+ [ $block_deletion = 0 ] && return 0
+
+ local rule_counter=`grep ^${slice_id} ${DBFILE} | wc -l`
+ [ $rule_counter -gt 1 ] && return 0 # there are still user rules
+ # delete the block and clean the table
+ local block_n=`grep "^${slice_id} BLOCK" ${DBFILE} | cut -d " " -f 3`
+ debug "Deleting BLOCK <${block_n}> entry from ipfw and from the database"
+ table_remove $slice_id $block_n
+}
+
+# compare the argument with the first two field of
+# the database.
+# On match returns the block number, otherwise returns 0.
+# no echo inside
+find_block() { # $1 slice_id
+ local ret
+ ret=`grep -- "^$1 BLOCK " $DBFILE`
+
+ [ x"$ret" = x ] && echo "0" && return # nothing found
+ # ignore multiple matches. If the db is corrupt we are
+ # screwed anyways
+ set $ret
+ echo "$3"
+}
+#
+# remove the default user rule and
+# the a BLOCK entry from ipfw and update the db
+# no echo inside
+table_remove() { # $slice_id $block_n
+ [ "$TEST" = "1" ] && return 0
+
+ # compute and delete the last user rule
+ local ipfw_rulemax=$(($IPFW_RULE_MIN + $(($M *${block_n})) -1))
+ ${IPFW} table $SLICE_TABLE delete $slice_id
+ ${IPFW} delete ${ipfw_rulemax}
+ ( grep -iv -- "^${slice_id} BLOCK ${block_n}" $DBFILE; ) > ${DBFILE}.tmp
+ mv ${DBFILE}.tmp ${DBFILE}
+ return 0
+}
+
+#
+# Find a rule and pipe_index for the given key (xid type arg)
+# Allocate a new block if first entry for this xid.
+# Rule and pipe are not written into the database, only the block is.
+#
+# Return ipfw_rule pipe_index new_rule
+# 'new_rule' is 0 if the rule existed, 1 if it is new
+#
+# return ipfw_rule = 0 if there are no resources available
+find_allocate() { # slice_id type arg
+ local slice_id=$1 type=$2 arg=$3
+ local ipfw_rule pipe_index new_block=0
+
+ # search for already allocated rule and pipes
+ set `find_rule $slice_id $type $arg`
+ ipfw_rule=$1; pipe_index=$2
+ [ ! ${ipfw_rule} = 0 ] && echo $ipfw_rule $pipe_index "0" && return 0 # rules found, return
+
+ # no rules found, search for an already existing block, or
+ # allocate a new one
+ local block_n=`find_block ${slice_id}`
+ [ ${block_n} = "0" ] && new_block=1 && block_n=`find_free_block`
+ [ ${block_n} = "0" -o ${block_n} -gt $BLOCK_MAX ] && echo 0 && return 0;
+
+ # We have a valid block, compute the range for user rules
+ local ipfw_rulemin=$(($IPFW_RULE_MIN + $(($M *$(($block_n - 1))))))
+ local ipfw_rulemax=$(($(($ipfw_rulemin + $M)) - 1 ))
+
+ # Find rule and pipes, reserve the last rule for the user's
+ # default rule that catches regular traffic.
+ set `allocate_resources $ipfw_rulemin $(($ipfw_rulemax - 1))`
+ ipfw_rule=$1; pipe_index=$2
+ [ $ipfw_rule = 0 ] && echo 0 && return 0 # no resources
+
+ # If this is a new block, add the slice to the lookup table
+ # and put a default rule at the end of the block.
+ if [ "$TEST" = "0" -a $new_block = 1 ] ; then
+ ${IPFW} table $SLICE_TABLE add ${slice_id} ${ipfw_rulemin} > /dev/null
+ ${IPFW} add ${ipfw_rulemax} allow all from any to any > /dev/null
+ ( echo "${slice_id} BLOCK ${block_n}" ) >> ${DBFILE}
+ fi
+
+ echo $ipfw_rule $pipe_index "1"
+ return 0
+}
+
+#
+# called with the database file as input
+# compare the tuple <slice_id type arg> with
+# the current firewall configuration. The database contains
+# slice_id type arg ipfw_rule pipe_index timeout
+# On match returns <ipfw_rule pipe_index timeout>
+# On non match returns 0 0 0
+# no echo inside
+find_rule() { # slice_id type arg
+ local ret
+ ret=`grep -i -- "^$1 $2 $3 " $DBFILE | grep -v BLOCK`
+
+ [ x"$ret" = x ] && echo "0 0 0 " && return # nothing found
+ # ignore multiple matches. If the db is corrupt we are
+ # screwed anyways
+ set $ret
+ echo "$4 $5 $6"
+}
+
+#
+# Find a hole in a list of numbers within a range (boundaries included)
+# The input is passed as a sorted list of numbers on stdin.
+# Return a "0" rule if there is no rule free
+find_hole() { # min max
+ local min=$1 cand=$1 max=$2 line
+ while read line ; do
+ [ $line -lt $min ] && continue
+ [ $line -ne $cand ] && break # found
+ [ $cand -ge $max ] && cand=0 && break # no space
+ cand=$(($cand + 1))
+ done
+ echo $cand
}
-# main starts here
+# XXX despite the name this does not allocate but only finds holes.
+# returns a free rule and pipe base for client|server|service
+# within a block
+# Returns r=0 if there are no resources available
+# no echo inside
+allocate_resources() { # ipfw_minrule ipfw_maxrule
+ local p r
+ # remove comments, extract field, sort
+ p=`grep -v '^#' $DBFILE | grep -v BLOCK | awk '{print $5}' | sort -n | \
+ find_hole $PIPE_MIN $PIPE_MAX`
+ r=`grep -v '^#' $DBFILE | grep -v BLOCK | awk '{print $4}' | sort -n | \
+ find_hole $1 $2`
+ [ $r = 0 -o $p = 0 ] && r=0 # no resources available
+ echo $r $p
+}
- debug "Debug activated"
- requests=[]
- i=0
- while read request
- do
- # read -a read arguments in array
- # XXX skip lines starting with #
- requests[$i]=$request;
- let i=$i+1
- done
+# Returns the index of a free block
+# Returns 0 if there are no resources available
+# no debug inside
+find_free_block() {
+ b=`grep -v '^#' $DBFILE | grep BLOCK | awk '{print $3}' | sort -n | \
+ find_hole $BLOCK_MIN $BLOCK_MAX`
+ echo $b
+}
+
+# parse the ipfw database and remove expired rules
+#
+# Each timeout value stored in the database is compared against
+# the current time. If the timeout is older than current,
+# the rules and related pipes will be deleted.
+kill_expired() { # slice_id type arg
+ local match timeout
+
+ # if there is no database file exit
+ [ ! -f ${DBFILE} ] && return 0
+
+ # Get the current time
+ now=`date -u +%s`
+
+ cp ${DBFILE} ${DBFILE}.kill
+ cat ${DBFILE}.kill | grep -v BLOCK |
+ while read line; do
+ match=`echo $line|cut -d " " -f 1-3`
+ timeout=`echo $line|cut -d " " -f 6`
+ [ $now -gt $timeout ] && do_delete 1 $match
+ done
+ rm ${DBFILE}.kill
+}
- # create the lock
+# execute functions from root context
+# can be used from root context as follow:
+# echo "super $command $args" | /vsys/ipfw-be 0
+do_super() { # $arguments...
+ case $1 in
+ init)
+ ipfw_init; return 0
+ ;;
+ dbcleanup)
+ clean_db; return 0
+ ;;
+ killexpired)
+ kill_expired; return 0
+ ;;
+ *)
+ abort "Invalid super command"
+ ;;
+ esac
+}
- # process requests
- for i in `/usr/bin/seq 0 $((${#requests[*]} - 1))`
- do
- process "${requests[$i]}"
- done
+# refresh the rule timeout
+do_refresh() { # slice_id type arg timeout
+ local ipfw_pipe_in ipfw_pipe_out pipe_index
+ local slice_id=$1 type=$2 arg=$3 timeout=$4
+
+ debug "do_refresh type: <$type> arg: <$arg> timeout: <$timeout>"
+ [ "${type}" = "BLOCK" ] && abort "BLOCK rule not valid"
+ [ "${timeout}" = "" ] && abort "Missing args on 'refresh', expected on of {SERVICE|SERVER|CLIENT} port_number"
+ set `find_rule $slice_id $type $arg`
+ ipfw_rule=$1; pipe_index=$2
+ [ "${ipfw_rule}" = "0" ] && debug "no rules found" && return 0 # no rules found
+
+ [ "$TEST" = "1" ] && return
+ # update the database with the new timeout value
+ ( grep -iv -- "^${slice_id} ${type} ${arg} " $DBFILE; \
+ echo "${slice_id} ${type} ${arg} ${ipfw_rule} ${pipe_index} ${timeout}" ) > ${DBFILE}.tmp
+ mv ${DBFILE}.tmp ${DBFILE}
+ echo "refreshed timeout for rule ${type} ${arg}"
+}
- # delete the lock
- exit 0
+# process a request.
+# A request is made by a set of arguments formatted as follow:
+#
+# config {server|client|service} arg [-t timeout] IN <pipe_conf> OUT <pipe_conf>
+# show {rules|pipes} [args]
+# delete type arg
+# refresh type arg [-t timeout]
+#
+# The timeout value is expressed as:
+# week, day, month or anything else accepted by the date command.
+# The id of the slice issuing the request is in the $SLICE_ID variable,
+# set at the beginning of this script.
+process() {
+ local new_pipe=0
+ local timeout TMP i rule_base pipe_base
+ local cmd=$1 ; shift
+ local debug_args="$*";
+ local type=$1 ; shift
+ local args="$*"
+ debug "Received command: <$cmd> arguments: <$debug_args>"
+
+ # set the timeout value
+ # if present, extract the '-t timeout' substring from the command line
+ timeout=`echo ${args} | ${SED} ${SEDOPT} 's/(.+)( -t [a-zA-Z0-9]+ )(.*)/\2/'`
+ # if the '-t timeout' is specified, use the timeout provided by the user
+ if [ "${timeout}" != "${args}" ] ; then # match
+ # remove the '-t ' option
+ timeout=`echo ${timeout} | ${SED} ${SEDOPT} 's/-t //'`
+ timeout=`check_timeout ${timeout}`
+ [ $timeout = 0 ] && abort "Date format $1 not valid"
+ # clean the arguments
+ args=`echo ${args} | ${SED} ${SEDOPT} 's/(.+)( -t [a-zA-Z0-9]+ )(.*)/\1 \3/'`
+ else
+ # use the default value, no need to check for correctness, no need to clean arguments
+ timeout=`date --date="1day" +%s` # default to 1 day
+ fi
+
+ # if the table rule is not present, add it
+ local table_rule=`${IPFW} show $S | grep "skipto tablearg" | grep "lookup jail $SLICE_TABLE"`
+ [ -z "$table_rule" ] && ipfw_init
+
+ debug "Timeout $timeout"
+ # Handle special requests: show and delete
+ case x"$cmd" in
+ x"config")
+ case x"$type" in
+ xserver|xSERVER|xclient|xCLIENT|xservice|xSERVICE)
+ do_config $SLICE_ID $timeout $type $args && return 0
+ ;;
+ esac
+ abort "'config' should be followed by {CLIENT|SERVER|SERVICE}"
+ ;;
+ x"delete")
+ do_delete 1 $SLICE_ID $type $args
+ ;;
+ x"refresh")
+ do_refresh $SLICE_ID $type $args $timeout && return 0
+ ;;
+ x"show")
+ # XXX filter out sliver rules
+ [ "$type" = "rules" ] && ${IPFW} show && return 0
+ [ "$type" = "pipes" ] && ${IPFW} pipe show && return 0
+ abort "'show' should be followed by {rules|pipes}"
+ ;;
+ x"super")
+ [ $SLICE_ID = 0 ] && do_super $type $args && return 0
+ abort "no permission for ipfw-be super execution"
+ ;;
+ x"help")
+ do_help && return 0
+ ;;
+ *)
+ # help XXX to be done
+ abort "'command' should be one of {show|config|delete|refresh|release}"
+ ;;
+ esac
+}
+
+# validate the timeout
+check_timeout() { # timeout
+ local tt=`date --date="${1}" +%s`
+ [ "$?" != "0" ] && echo 0 && return
+ echo $tt
+}
+
+do_config() { # slice_id timeout type arg IN pipe_conf OUT pipe_conf
+ local slice_id=$1; shift
+ local timeout=$1; shift
+ local type=$1; shift
+ local arg=$1; shift # XXX addr not yet implemented
+ local p h; # port and optional hostname
+
+ [ "$1" != "IN" ] && abort "Missing addr:port, or IN requested"
+ shift
+
+ # read pipe in configuration
+ i=""
+ while [ "$1" != "" -a "$1" != "OUT" ] ; do
+ i="$i $1"
+ shift
+ done
+ CONFIG_PIPE_IN="$i" # XXX local ?
+ [ "$CONFIG_PIPE_IN" = "" ] && abort "Missing pipe in configuration"
+
+ [ "$1" != "OUT" ] && abort "Missing pipe in configuration, or missing OUT"
+ shift
+
+ # read pipe out configuration
+ i=""
+ while [ "$1" != "" ] ; do
+ i="$i $1"
+ shift
+ done
+ CONFIG_PIPE_OUT="$i" # XXX local ?
+ [ "$CONFIG_PIPE_OUT" = "" ] && abort "Missing pipe out configuration"
+
+
+ # process the argument (port and hostname are separated by a @)
+ # split the argument, and prepare the remote host configuration string
+ p=`echo $arg | cut -s -d "@" -f1-` # empty it there is no separator
+ if [ "$p" = "" ] ; then
+ p=$arg
+ else
+ p=`echo $arg | cut -d "@" -f1`
+ h=`echo $arg | cut -d "@" -f2`
+ fi
+
+ # A port value is mandatory
+ [ "$p" = "" ] && abort "A port value is mandatory."
+
+ # SERVICE do not support remote hostname filtering
+ [ $type = "service" ] && [ "$h" != "" ] && \
+ abort "The service configuration do not support filtering remote hostnames."
+
+ debug "Configuration Required:"
+ debug "slice_id: $SLICE_ID"
+ debug "type: $type"
+ debug "full arg: $arg"
+ debug "mandatory port(s): $p optional hostname(s): $h"
+ debug "timeout: $timeout"
+ debug "IN: $CONFIG_PIPE_IN"
+ debug "OUT: $CONFIG_PIPE_OUT"
+ debug "-----------------------"
+
+ # check if the link is already configured
+ debug "Search for slice_id: ${slice_id} type: ${type} port: ${arg}"
+
+ set `find_allocate ${slice_id} ${type} ${arg}`
+ local ipfw_rule=$1 pipe_index=$2 new_rule=$3
+
+ [ ${ipfw_rule} = 0 ] && abort "No resources available"
+ debug "Found or allocated resources ipfw_rule: ${ipfw_rule} and pipe_index: ${pipe_index}"
+
+ add_rule $slice_id $new_rule $type $arg $ipfw_rule $pipe_index $timeout
+ hook_call $type $port $rule_base $pipe_base $timeout
+ return 0; # link configured, exit
+}
+
+#
+# acquire the lock XXX check lockfile
+acquire_lock() {
+ [ "$TEST" = 1 ] && return
+ lockfile -s 0 -r 0 $lockfile 2> /dev/null
+ if [ $? -ne 0 ] ; then
+ echo "lock acquisition failed"
+ exit -1
+ fi
+}
+
+#
+# release the lock
+release_lock() {
+ rm -f $lockfile
+}
+
+#
+# initialize the firewall with PlanetLab default rules
+ipfw_init() {
+ ${IPFW} -q delete $S
+ ${IPFW} -q delete $D
+ ${IPFW} add $S skipto tablearg lookup jail $SLICE_TABLE
+ ${IPFW} add $D allow all from any to any
+}
+
+#
+# if present, call a hook function
+# Arguments are:
+# slice_id type port rule_base pipe_base timeout
+hook_call() {
+ if [ -n "${HOOK}" -a -x "${HOOK}" ]; then
+ debug "Calling the hook function."
+ ${HOOK} ${SLICE_ID} "$*" &
+ fi
+}
+
+do_help() {
+ cat << EOF
+Usage:
+ ./neconfig {CLIENT|SERVER|SERVICE} arg [-t timeout] \
+ IN <pipe in configuration> OUT <pipe out configuration>
+ ./netconfig show {rules|pipes}
+ ./netconfig delete {CLIENT|SERVER|SERVICE} arg
+ ./netconfig refresh [-t timeout] {CLIENT|SERVER|SERVICE} arg
+
+We support three modes of operation:
+
+ CLIENT programs on the node connect to remote ports
+ and/or addresses. Emulation intercepts traffic
+ involving those ports/addresses
+
+ SERVER programs on the node listen on specific ports.
+ Emulation intercepts traffic on those ports,
+ optionally limited to specific client addresses.
+
+ SERVICE the node runs both clients and servers,
+ we can only specify the ports on which emulation
+ is configured.
+
+ 'arg' has the form PORTLIST[@ADDRLIST], where ADDRLIST is
+ optional and only supported for CLIENT and SERVER modes.
+ PORTLIST and ADDRLIST can be specified as any valid port
+ or address specifier in ipfw, e.g.
+ - a single value 443 or 10.20.30.40/24
+ - a comma-separated list 1111,2222,3333 1.2.3.4,5.6.7.8
+ - a range 1111-2222 (only for ports)
+ Addresses can also be specified as symbolic hostnames, and
+ they are resolved when the rule is installed.
+ Note that they always indicate the remote endpoint.
+
+ On a given port a user can have one CLIENT and/or one SERVER
+ configuration or one SERVICE configuration.
+ When a SERVICE configuration is installed any existing CLIENT
+ and SERVER configuration on the same port are removed.
+ When a CLIENT or SERVER configuration is installed any existing
+ SERVICE configuration on the same port is removed.
+
+The pipe's configuration, both for the upstream and downstream link,
+follows the dummynet syntax. A quick and not exaustive example
+of the parameters that can be used to configure the delay,
+the bandwidth and the packet loss rate for a link follow:
+
+ IN|OUT delay 100ms bw 1Mbit/s plr 0.1
+
+The profile file, if present, should be located into the sliver's
+root directory.
+The full documentation is on the manpage[1].
+
+The timeout value follow the linux 'date' command format[2]
+and can be specified as follow:
+ 1week
+ 2hours
+ 3days
+
+--- References:
+[1] http://www.freebsd.org/cgi/man.cgi?query=ipfw
+[2] http://linuxmanpages.com/man1/date.1.php
+EOF
+}
+
+#--- DOCUMENTATION AND INTERNAL ARCHITECTURE ---
+#
+# When a user configures an emulated link, we need to allocate
+# two pipes and one ipfw rule number to store the parameters.
+# Reconfigurations of existing links reuse the previous resources.
+# We keep track of all resources (pipes, rules and blocks of rules)
+# in a database stored in a text file, see DATABASE FORMAT below.
+#
+# Pipes are allocated in pairs. In the database each pair is numbered
+# from PIPE_MIN to PIPE_MAX. The actual pipe numbers for each pair are
+#
+# ipfw_pipein = IPFW_PIPE_MIN + 2*(pipe_index-1)
+# ipfw_pipeout = ipfw_pipein + 1
+#
+# The rules number is allocated within a block of M consecutive rules
+# for each slice. The block is allocated at the first configuration
+# of an emulated link, and deallocated when the last link is removed.
+# In the database, blocks are numbered from BLOCK_MIN to BLOCK_MAX,
+# and the range of rules for a given block_index is
+#
+# ipfw_min_rule = RULE_BASE
+# ipfw_max_rule = RULE_BASE + ((M-1)*block_index) -1
+#
+# All lookups, and the block allocation, are done in find_allocate().
+# The rule_number and pipe_index are written in the database
+# by add_rule() after checking the correctness of the request.
+#
+#
+#--- RULESET STRUCTURE ---
+# The ruleset is made of different sections, as follows:
+# - an initial block of rules, reserved and configurable by
+# the root context only;
+# - a skipto rule (S), used to jump directly to the block
+# associated with a given slice;
+# - a second block of reserved rules, to catch remaining traffic.
+# This ends with rule number D which is an 'accept all';
+# - after D, we have a block of M rule numbers for each slice.
+# Each of these blocks ends with an 'accept all' rule;
+# - finally, rule 65535 is the firewall's default rule.
+#
+# To summarize:
+# 1...S-1 first block of reserved rules
+# S skipto tablearg lookup jail 1
+# S+1..D-1 ... second block of reserved rules
+# D allow ip from any to any
+#
+# RULE_BASE <block of M entries for first user>
+# RULE_BASE+M <block of M entry for second user ...>
+# ...
+#
+#--- DATABASE FORMAT ---
+# The database is stored in a text file, and contains one record per
+# line with the following structure
+#
+# XID TYPE arg1 arg2 ...
+#
+# Whitespace separates the fields. arg1, arg2, ... have different
+# meaning depending on the TYPE. XID is the slice ID.
+#
+# In the database we have the following records:
+# - one entry of type BLOCK for each slice with configured links.
+# This entry represents the block_index of the block of M ipfw
+# rules allocated to the slice, as follows:
+#
+# XID BLOCK block_index
+# (BLOCK_MIN <= block_index <= BLOCK_MAX)
+#
+# - one entry for each link (CLIENT, SERVER, SERVICE).
+# The database entry for this info has the form
+#
+# XID {CLIENT|SERVER|SERVICE} arg ipfw_rule pipe_index timeout
+#
+# 'TYPE' reflects the configuration mode;
+# 'arg' is PORTLIST@ADDRLIST and is used as a search key together
+# with the XID and TYPE;
+# 'ipfw_rule' is the unique ipfw rule number used for this
+# emulated link. It must be within the block of M rule numbers
+# allocated to the slice;
+# 'pipe_index' is the index of the pair of pipes used for the
+# configuration;
+
+#-- main starts here
+debug "--- $0 START for $SLICENAME ---"
+
+# If the db does not exist, create it and clean rules and pipes
+[ ! -e ${DBFILE} ] && clean_db
+
+# A request to the vsys backend is composed by a single line of input
+read REQ # read one line, ignore the rest
+set_verbose ${REQ} # use inital -v if present
+set_test ${REQ} # use inital -t if present
+REQ="`filter ${REQ}`" # remove -v and -q and invalid chars
+debug "--- processing <${REQ}>"
+acquire_lock # critical section
+process ${REQ}
+release_lock
+debug "--- $0 END ---"
+exit 0