Move DNAT/REDIRECT processing code to lib.nat

git-svn-id: https://shorewall.svn.sourceforge.net/svnroot/shorewall/trunk@4817 fbd18981-670d-0410-9b5c-8dc0c1a9a2bb
This commit is contained in:
teastep 2006-11-09 04:18:49 +00:00
parent 71b29cfe99
commit bad66d0f1a
4 changed files with 196 additions and 191 deletions

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@ -15,6 +15,8 @@ Changes in 3.3.4
7) Fix whitespace in LOGFORMAT.
8) Move DNAT/REDIRECT code to lib.base.
Changes in 3.3.4
1) Make exclusion work with "show zones"

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@ -1596,195 +1596,6 @@ __EOF__
done
}
#
# Add a NAT rule - Helper function for the rules file processor
#
# The caller has established the following variables:
# cli = Source IP, interface or MAC Specification
# serv = Destination IP Specification
# servport = Port the server is listening on
# dest_interface = Destination Interface Specification
# proto = Protocol Specification
# addr = Original Destination Address
# dports = Destination Port Specification. 'dports' may be changed
# by this function
# cport = Source Port Specification
# multiport = String to invoke multiport match if appropriate
# ratelimit = Optional rate limiting clause
# userandgroup = -m owner match to limit the rule to a particular user and/or group
# logtag = Log tag
# excludesource = Source Exclusion List
#
add_nat_rule() {
local chain
local excludedests=
# Be sure we can NAT
if [ -z "$NAT_ENABLED" ]; then
fatal_error "Rule \"$rule\" requires NAT which is disabled"
fi
# Parse SNAT address if any
if [ "$addr" != "${addr%:*}" ]; then
fatal_error "SNAT may no longer be specified in a DNAT rule; use ${CONFDIR}/masq instead"
fi
# Set original destination address
case $addr in
all)
addr=
;;
detect)
eval interfaces=\$${source}_interfaces
if [ -n "$DETECT_DNAT_IPADDRS" -a "$source" != "$FW" ]; then
save_command
if [ $(list_count1 $interfaces) -eq 1 ]; then
save_command "addr=\$(find_first_interface_address $interfaces)"
else
save_command "addr="
for interface in $interfaces; do
ident >&3 << __EOF__
addr="\$addr \$(find_first_interface_address $interface)"
__EOF__
done
fi
else
addr=
fi
;;
!*)
if [ $(list_count $addr) -gt 1 ]; then
excludedests="${addr#\!}"
addr=
fi
;;
esac
addr=${addr:-0.0.0.0/0}
# Select target
if [ "$logtarget" = SAME ]; then
[ -n "$servport" ] && fatal_error "Port mapping not allowed in SAME rules"
serv1=
for srv in $(separate_list $serv); do
serv1="$serv1 --to ${srv}"
done
target1="SAME $serv1"
elif [ -n "$serv" ]; then
servport="${servport:+:$servport}"
serv1=
for srv in $(separate_list $serv); do
serv1="$serv1 --to-destination ${srv}${servport}"
done
target1="DNAT $serv1"
else
target1="REDIRECT --to-port $servport"
fi
# Generate nat table rules
if [ "$source" = "$FW" ]; then
if [ -n "${excludesource}${excludedests}" ]; then
build_exclusion_chain chain nat "$excludesource" $excludedests
for adr in $(separate_list $addr); do
run_iptables2 -t nat -A OUTPUT $cli $proto $userandgroup $multiport $sports $dports $(dest_ip_range $adr) -j $chain
done
if [ -n "$loglevel" ]; then
log_rule_limit $loglevel $chain OUTPUT $logtarget "$ratelimit" "$logtag" -A -t nat
fi
addnatrule $chain $ratelimit $proto -j $target1 # Protocol is necessary for port redirection
else
for adr in $(separate_list $addr); do
if [ -n "$loglevel" ]; then
log_rule_limit $loglevel OUTPUT OUTPUT $logtarget "$ratelimit" "$logtag" -A -t nat \
$(fix_bang $proto $cli $sports $userandgroup $(dest_ip_range $adr) $multiport $dports)
fi
run_iptables2 -t nat -A OUTPUT $ratelimit $proto $sports $userandgroup $(dest_ip_range $adr) $multiport $dports -j $target1
done
fi
else
if [ -n "${excludesource}${excludedests}" ]; then
build_exclusion_chain chain nat "$excludesource" $excludedests
if [ $addr = detect ]; then
ensurenatchain $(dnat_chain $source)
#
# The 'for loops' begun below are completed in add_a_rule() whose declaration follows
#
indent >&3 << __EOF__
for adr in \$addr; do
run_iptables -t nat -A $(fix_bang $(dnat_chain $source) $cli $proto $multiport $sports $dports) -d \$adr -j $chain
__EOF__
else
for adr in $(separate_list $addr); do
addnatrule $(dnat_chain $source) $cli $proto $multiport $sports $dports $(dest_ip_range $adr) -j $chain
done
fi
if [ -n "$loglevel" ]; then
log_rule_limit $loglevel $chain $(dnat_chain $source) $logtarget "$ratelimit" "$logtag" -A -t nat
fi
addnatrule $chain $ratelimit $proto -j $target1 # Protocol is necessary for port redirection
else
chain=$(dnat_chain $source)
if [ $addr = detect ]; then
ensurenatchain $chain
indent >&3 << __EOF__
for adr in \$addr; do
__EOF__
if [ -n "$loglevel" ]; then
indent >&3 << __EOF__
log_rule_limit $loglevel $chain $chain $logtarget "$ratelimit" "$logtag" -A -t nat $(fix_bang $proto $cli $sports $multiport $dports) -d \$adr
__EOF__
fi
indent >&3 << __EOF__
run_iptables -t nat -A $chain $(fix_bang $proto $ratelimit $cli $sports $multiport $dports) -d \$adr -j $target1
__EOF__
else
for adr in $(separate_list $addr); do
if [ -n "$loglevel" ]; then
ensurenatchain $chain
log_rule_limit $loglevel $chain $chain $logtarget "$ratelimit" "$logtag" -A -t nat \
$(fix_bang $proto $cli $sports $(dest_ip_range $adr) $multiport $dports)
fi
addnatrule $chain $proto $ratelimit $cli $sports \
-d $adr $multiport $dports -j $target1
done
fi
fi
fi
# Replace destination port by the new destination port
if [ -n "$servport" ]; then
if [ -z "$multiport" ]; then
dports="--dport ${servport#*:}"
else
dports="--dports ${servport#*:}"
fi
fi
[ "x$addr" = "x0.0.0.0/0" ] && addr=
ratelimit=
}
#
# Add one Filter Rule
#
@ -2028,6 +1839,7 @@ add_a_rule() {
# A specific server or server port given
if [ -n "$natrule" ]; then
lib_load nat "$logtarget Rules"
add_nat_rule
[ $policy = ACCEPT ] && return
elif [ -n "$servport" -a "$servport" != "$port" ]; then

View File

@ -22,7 +22,8 @@
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA
#
# This library is loaded by /usr/share/shorewall/compiler when any of the following
# configuration files are non-empty: masq, nat, netmap
# configuration files are non-empty: masq, nat, netmap; or when there are
# DNAT/REDIRECT rules in the /etc/shorewall/rules file.
#
#
@ -580,3 +581,192 @@ setup_netmap() {
done < $TMP_DIR/netmap
}
#
# Add a NAT rule - Helper function for the rules file processor
#
# The caller has established the following variables:
# cli = Source IP, interface or MAC Specification
# serv = Destination IP Specification
# servport = Port the server is listening on
# dest_interface = Destination Interface Specification
# proto = Protocol Specification
# addr = Original Destination Address
# dports = Destination Port Specification. 'dports' may be changed
# by this function
# cport = Source Port Specification
# multiport = String to invoke multiport match if appropriate
# ratelimit = Optional rate limiting clause
# userandgroup = -m owner match to limit the rule to a particular user and/or group
# logtag = Log tag
# excludesource = Source Exclusion List
#
add_nat_rule() {
local chain
local excludedests=
# Be sure we can NAT
if [ -z "$NAT_ENABLED" ]; then
fatal_error "Rule \"$rule\" requires NAT which is disabled"
fi
# Parse SNAT address if any
if [ "$addr" != "${addr%:*}" ]; then
fatal_error "SNAT may no longer be specified in a DNAT rule; use ${CONFDIR}/masq instead"
fi
# Set original destination address
case $addr in
all)
addr=
;;
detect)
eval interfaces=\$${source}_interfaces
if [ -n "$DETECT_DNAT_IPADDRS" -a "$source" != "$FW" ]; then
save_command
if [ $(list_count1 $interfaces) -eq 1 ]; then
save_command "addr=\$(find_first_interface_address $interfaces)"
else
save_command "addr="
for interface in $interfaces; do
ident >&3 << __EOF__
addr="\$addr \$(find_first_interface_address $interface)"
__EOF__
done
fi
else
addr=
fi
;;
!*)
if [ $(list_count $addr) -gt 1 ]; then
excludedests="${addr#\!}"
addr=
fi
;;
esac
addr=${addr:-0.0.0.0/0}
# Select target
if [ "$logtarget" = SAME ]; then
[ -n "$servport" ] && fatal_error "Port mapping not allowed in SAME rules"
serv1=
for srv in $(separate_list $serv); do
serv1="$serv1 --to ${srv}"
done
target1="SAME $serv1"
elif [ -n "$serv" ]; then
servport="${servport:+:$servport}"
serv1=
for srv in $(separate_list $serv); do
serv1="$serv1 --to-destination ${srv}${servport}"
done
target1="DNAT $serv1"
else
target1="REDIRECT --to-port $servport"
fi
# Generate nat table rules
if [ "$source" = "$FW" ]; then
if [ -n "${excludesource}${excludedests}" ]; then
build_exclusion_chain chain nat "$excludesource" $excludedests
for adr in $(separate_list $addr); do
run_iptables2 -t nat -A OUTPUT $cli $proto $userandgroup $multiport $sports $dports $(dest_ip_range $adr) -j $chain
done
if [ -n "$loglevel" ]; then
log_rule_limit $loglevel $chain OUTPUT $logtarget "$ratelimit" "$logtag" -A -t nat
fi
addnatrule $chain $ratelimit $proto -j $target1 # Protocol is necessary for port redirection
else
for adr in $(separate_list $addr); do
if [ -n "$loglevel" ]; then
log_rule_limit $loglevel OUTPUT OUTPUT $logtarget "$ratelimit" "$logtag" -A -t nat \
$(fix_bang $proto $cli $sports $userandgroup $(dest_ip_range $adr) $multiport $dports)
fi
run_iptables2 -t nat -A OUTPUT $ratelimit $proto $sports $userandgroup $(dest_ip_range $adr) $multiport $dports -j $target1
done
fi
else
if [ -n "${excludesource}${excludedests}" ]; then
build_exclusion_chain chain nat "$excludesource" $excludedests
if [ $addr = detect ]; then
ensurenatchain $(dnat_chain $source)
#
# The 'for loops' begun below are completed in add_a_rule() whose declaration follows
#
indent >&3 << __EOF__
for adr in \$addr; do
run_iptables -t nat -A $(fix_bang $(dnat_chain $source) $cli $proto $multiport $sports $dports) -d \$adr -j $chain
__EOF__
else
for adr in $(separate_list $addr); do
addnatrule $(dnat_chain $source) $cli $proto $multiport $sports $dports $(dest_ip_range $adr) -j $chain
done
fi
if [ -n "$loglevel" ]; then
log_rule_limit $loglevel $chain $(dnat_chain $source) $logtarget "$ratelimit" "$logtag" -A -t nat
fi
addnatrule $chain $ratelimit $proto -j $target1 # Protocol is necessary for port redirection
else
chain=$(dnat_chain $source)
if [ $addr = detect ]; then
ensurenatchain $chain
indent >&3 << __EOF__
for adr in \$addr; do
__EOF__
if [ -n "$loglevel" ]; then
indent >&3 << __EOF__
log_rule_limit $loglevel $chain $chain $logtarget "$ratelimit" "$logtag" -A -t nat $(fix_bang $proto $cli $sports $multiport $dports) -d \$adr
__EOF__
fi
indent >&3 << __EOF__
run_iptables -t nat -A $chain $(fix_bang $proto $ratelimit $cli $sports $multiport $dports) -d \$adr -j $target1
__EOF__
else
for adr in $(separate_list $addr); do
if [ -n "$loglevel" ]; then
ensurenatchain $chain
log_rule_limit $loglevel $chain $chain $logtarget "$ratelimit" "$logtag" -A -t nat \
$(fix_bang $proto $cli $sports $(dest_ip_range $adr) $multiport $dports)
fi
addnatrule $chain $proto $ratelimit $cli $sports \
-d $adr $multiport $dports -j $target1
done
fi
fi
fi
# Replace destination port by the new destination port
if [ -n "$servport" ]; then
if [ -z "$multiport" ]; then
dports="--dport ${servport#*:}"
else
dports="--dports ${servport#*:}"
fi
fi
[ "x$addr" = "x0.0.0.0/0" ] && addr=
ratelimit=
}

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@ -122,7 +122,8 @@ New Features:
option in /etc/shorewall/interfaces or /etc/shorewall/hosts.
- lib.nat. Must be available if you have entries in
/etc/shorewall/masq, /etc/shorewall/nat or /etc/shorewall/netmap.
/etc/shorewall/masq, /etc/shorewall/nat or /etc/shorewall/netmap
or if you use DNAT or REDIRECT rules.
- lib.providers. Must be available if you have entries in
/etc/shorewall/providers.