SHOREWALL6-TCRULES(5) [FIXME: manual] SHOREWALL6-TCRULES(5)
NAME
tcrules - Shorewall6 Packet Marking rules file
SYNOPSIS
/etc/shorewall6/tcrules
DESCRIPTION
Entries in this file cause packets to be marked as a means of classifying them for traffic control or policy routing.
Important
Unlike rules in the shorewall6-rules[1](5) file, evaluation of rules in this file will continue after a match. So the final mark for
each packet will be the one assigned by the LAST tcrule that matches.
If you use multiple internet providers with the 'track' option, in /etc/shorewall6/providers be sure to read the restrictions at
http://shorewall.net/MultiISP.html.
Beginning with Shorewall 4.5.4, the tcrules file supports two different formats:
FORMAT 1 (default - deprecated)
The older limited-function version of TPROXY is supported.
FORMAT 2
The newer version of TPROXY is supported.
The format is specified by a line as follows:
FORMAT {1|2}
The columns in the file are as follows (where the column name is followed by a different name in parentheses, the different name is used in
the alternate specification syntax).
ACTION - action
action may assume one of the following values.
1. A mark value which is an integer in the range 1-255.
Normally will set the mark value. If preceded by a vertical bar ("|"), the mark value will be logically ORed with the current mark
value to produce a new mark value. If preceded by an ampersand ("&"), will be logically ANDed with the current mark value to
produce a new mark value.
Both "|" and "&" require Extended MARK Target support in your kernel and ip6tables; neither may be used with connection marks (see
below).
May optionally be followed by :P, :F or :T, :I where :P indicates that marking should occur in the PREROUTING chain, :F indicates
that marking should occur in the FORWARD chain, :I indicates that marking should occur in the INPUT chain (added in Shorewall
4.4.13) and :T indicates that marking should occur in the POSTROUTING chain. If neither :P, :F nor :T follow the mark value then
the chain is determined as follows:
- If the SOURCE is $FW[:address-or-range[,address-or-range]...], then the rule is inserted into the OUTPUT chain. The behavior
changed in Shorewall6-perl 4.1. Only high mark values may be assigned in this case. Packet marking rules for traffic shaping of
packets originating on the firewall must be coded in the POSTROUTING chain (see below).
- Otherwise, the chain is determined by the setting of MARK_IN_FORWARD_CHAIN in shorewall6.conf[2](5).
Please note that :I is included for completeness and affects neither traffic shaping nor policy routing.
If your kernel and ip6tables include CONNMARK support then you can also mark the connection rather than the packet.
The mark value may be optionally followed by "/" and a mask value (used to determine those bits of the connection mark to actually
be set). The mark and optional mask are then followed by one of:+
C
Mark the connection in the chain determined by the setting of MARK_IN_FORWARD_CHAIN
CF
Mark the connection in the FORWARD chain
CP
Mark the connection in the PREROUTING chain.
CT
Mark the connection in the POSTROUTING chain
CI
Mark the connection in the INPUT chain. This option is included for completeness and has no applicability to traffic shaping or
policy routing.
Special considerations for If HIGH_ROUTE_MARKS=Yes in shorewall6.conf[2](5).
If HIGH_ROUTE_MARKS=Yes, then you may also specify a value in the range 0x0100-0xFF00 with the low-order byte being zero. Such
values may only be used in the PREROUTING chain (value followed by :P or you have set MARK_IN_FORWARD_CHAIN=No in
shorewall6.conf[2](5) and have not followed the value with :F) or the OUTPUT chain (SOURCE is $FW). With HIGH_ROUTE_MARKS=Yes,
non-zero mark values less that 256 are not permitted. Shorewall6 prohibits non-zero mark values less that 256 in the OUTPUT chain
when HIGH_ROUTE_MARKS=Yes. While earlier versions allow such values in the OUTPUT chain, it is strongly recommended that with
HIGH_ROUTE_MARKS=Yes, you use the POSTROUTING chain to apply traffic shaping marks/classification.
2. A classification Id (classid) of the form major:minor where major and minor are integers. Corresponds to the 'class' specification
in these traffic shaping modules:
atm
cbq
dsmark
pfifo_fast
htb
prio
Classification occurs in the POSTROUTING chain except when the SOURCE is $FW[:address] in which case classification occurs in the
OUTPUT chain.
When using Shorewall6's built-in traffic shaping tool, the major class is the device number (the first device in
shorewall6-tcdevices[3](5) is major class 1, the second device is major class 2, and so on) and the minor class is the class's MARK
value in shorewall6-tcclasses[4](5) preceded by the number 1 (MARK 1 corresponds to minor class 11, MARK 5 corresponds to minor
class 15, MARK 22 corresponds to minor class 122, etc.).
Beginning with Shorewall 4.4.27, the classid may be optionally followed by ':' and a capital letter designating the chain where
classification is to occur.
F
FORWARD chain.
T
POSTROUTING chain (default).
3. RESTORE[/mask] -- restore the packet's mark from the connection's mark using the supplied mask if any. Your kernel and ip6tables
must include CONNMARK support.
As in 1) above, may be followed by :P or :F
4. SAVE[/mask] -- save the packet's mark to the connection's mark using the supplied mask if any. Your kernel and ip6tables must
include CONNMARK support.
As in 1) above, may be followed by :P or :F
5. CONTINUE Don't process any more marking rules in the table.
As in 1) above, may be followed by :P or :F. Currently, CONTINUE may not be used with exclusion (see the SOURCE and DEST columns
below); that restriction will be removed when ip6tables/Netfilter provides the necessary support.
6. SAME (Added in Shorewall 4.3.5) -- Some websites run applications that require multiple connections from a client browser. Where
multiple 'balanced' providers are configured, this can lead to problems when some of the connections are routed through one
provider and some through another. The SAME target allows you to work around that problem. SAME may be used in the PREROUTING and
OUTPUT chains. When used in PREROUTING, it causes matching connections from an individual local system to all use the same
provider. For example:
#ACTION SOURCE DEST PROTO DEST
# PORT(S)
SAME:P 192.168.1.0/24 0.0.0.0/0 tcp 80,443
If a host in 192.168.1.0/24 attempts a connection on TCP port 80 or 443 and it has sent a packet on either of those ports in the
last five minutes then the new connection will use the same provider as the connection over which that last packet was sent.
When used in the OUTPUT chain, it causes all matching connections to an individual remote system to all use the same provider. For
example:
#ACTION SOURCE DEST PROTO DEST
# PORT(S)
SAME $FW 0.0.0.0/0 tcp 80,443
If the firewall attempts a connection on TCP port 80 or 443 and it has sent a packet on either of those ports in the last five
minutes to the same remote system then the new connection will use the same provider as the connection over which that last packet
was sent.
7. COMMENT -- the rest of the line will be attached as a comment to the Netfilter rule(s) generated by the following entries. The
comment will appear delimited by "/* ... */" in the output of shorewall6 show mangle
To stop the comment from being attached to further rules, simply include COMMENT on a line by itself.
8. DIVERT
Added in Shorewall 4.5.3. Two DIVERT rule should preceed the TPROXY rule and should select DEST PORT tcp 80 and SOURCE PORT tcp 80
respectively (assuming that tcp port 80 is being proxied). DIVERT avoids sending packets to the TPROXY target once a socket
connection to Squid3 has been established by TPROXY. DIVERT marks the packet with a unique mark and exempts it from any rules that
follow.
9. TPROXY(mark[,[port][,[address]]]) -- FORMAT 1
Transparently redirects a packet without altering the IP header. Requires a local provider to be defined in
shorewall6-providers[5](5).
There are three parameters to TPROXY - only the first (mark) is required:
o mark - the MARK value corresponding to the local provider in shorewall6-providers[5](5).
o port - the port on which the proxy server is listening. If omitted, the original destination port.
o address - a local (to the firewall) IP address on which the proxy server is listening. If omitted, the IP address of the
interface on which the request arrives.
10. TPROXY([port][,[address]]]) -- FORMAT 2
Transparently redirects a packet without altering the IP header. Requires a local provider to be defined in
shorewall6-providers[5](5).
There are three parameters to TPROXY - only the first (mark) is required:
o port - the port on which the proxy server is listening. If omitted, the original destination port.
o address - a local (to the firewall) IP address on which the proxy server is listening. If omitted, the IP address of the
interface on which the request arrives.
11. HL([-|+]number)
Added in Shorewall 4.4.24. May be option followed by :F but the resulting rule is always added to the FORWARD chain. If + is
included, packets matching the rule will have their HL (hop limit) incremented by number. Similarly, if - is included, matching
packets have their HL decremented by number. If neither + nor - is given, the HL of matching packets is set to number. The valid
range of values for number is 1-255.
12. IMQ(number)
Added in Shorewall 4.5.1. Specifies that the packet should be passed to the IMQ identified by number. Requires IMQ Target support
in your kernel and ip6tables.
13. DSCP(dscp)
Added in Shorewall 4.5.1. Sets the Differentiated Services Code Point field in the IP header. The dscp value may be given as an
even number (hex or decimal) or as the name of a DSCP class. Valid class names and their associated hex numeric values are:
CS0 => 0x00
CS1 => 0x08
CS2 => 0x10
CS3 => 0x18
CS4 => 0x20
CS5 => 0x28
CS6 => 0x30
CS7 => 0x38
BE => 0x00
AF11 => 0x0a
AF12 => 0x0c
AF13 => 0x0e
AF21 => 0x12
AF22 => 0x14
AF23 => 0x16
AF31 => 0x1a
AF32 => 0x1c
AF33 => 0x1e
AF41 => 0x22
AF42 => 0x24
AF43 => 0x26
EF => 0x2e
May be optionally followed by ':' and a capital letter designating the chain where classification is to occur.
F
FORWARD chain.
T
POSTROUTING chain.
14. TOS(tos[/mask])
Added in Shorewall 4.5.1. Sets the Type of Service field in the IP header. The tos value may be given as an number (hex or decimal)
or as the name of a TOS type. Valid type names and their associated hex numeric values are:
Minimize-Delay => 0x10,
Maximize-Throughput => 0x08,
Maximize-Reliability => 0x04,
Minimize-Cost => 0x02,
Normal-Service => 0x00
When tos is given as a number, it may be optionally followed by '/' and a mask. When no mask is given, the value 0xff is assumed.
When tos is given as a type name, the mask 0x3f is assumed.
The action performed is to zero out the bits specified by the mask, then set the bits specified by tos.
May be optionally followed by ':' and a capital letter designating the chain where classification is to occur.
F
FORWARD chain.
T
POSTROUTING chain (default).
SOURCE - {-|{interface|$FW}|[{interface|$FW}:]<address-or-range[,address-or-range]...}[exclusion]>
Source of the packet. A comma-separated list of interface names, IP addresses, MAC addresses and/or subnets for packets being routed
through a common path. List elements may also consist of an interface name followed by ":" and an address (e.g.,
eth1:<2002:ce7c:92b4::/48>). For example, all packets for connections masqueraded to eth0 from other interfaces can be matched in a
single rule with several alternative SOURCE criteria. However, a connection whose packets gets to eth0 in a different way, e.g., direct
from the firewall itself, needs a different rule.
Accordingly, use $FW in its own separate rule for packets originating on the firewall. In such a rule, the ACTION column may NOT
specify either :P or :F because marking for firewall-originated packets always occurs in the OUTPUT chain.
MAC addresses must be prefixed with "~" and use "-" as a separator.
Example: ~00-A0-C9-15-39-78
When an interface is not specified, the angled brackets ('<' and '>') surrounding the address(es) may be omitted.
You may exclude certain hosts from the set already defined through use of an exclusion (see shorewall6-exclusion[6](5)).
DEST - {-|{interface|$FW}[{interface|$FW}:]<address-or-range[,address-or-range]...}[exclusion]>
Destination of the packet. Comma separated list of IP addresses and/or subnets. If your kernel and ip6tables include iprange match
support, IP address ranges are also allowed. List elements may also consist of an interface name followed by ":" and an address (e.g.,
eth1:<2002:ce7c:92b4::/48>). If the ACTION column specificies a classification of the form major:minor then this column may also
contain an interface name.
When an interface is not specified, the angled brackets ('<' and '>') surrounding the address(es) may be omitted.
Beginning with Shorewall 4.4.13, $FW may be given by itself or qualified by an address list. This causes marking to occur in the INPUT
chain.
You may exclude certain hosts from the set already defined through use of an exclusion (see shorewall6-exclusion[6](5)).
PROTO - {-|tcp:syn|ipp2p|ipp2p:udp|ipp2p:all|protocol-number|protocol-name|all}
Protocol - ipp2p requires ipp2p match support in your kernel and ip6tables.
PORT(S) (dport) - [-|port-name-number-or-range[,port-name-number-or-range]...]
Optional destination Ports. A comma-separated list of Port names (from services(5)), port numbers or port ranges; if the protocol is
ipv6-icmp, this column is interpreted as the destination icmp-type(s). ICMP types may be specified as a numeric type, a numberic type
and code separated by a slash (e.g., 3/4), or a typename. See http://www.shorewall.net/configuration_file_basics.htm#ICMP.
If the protocol is ipp2p, this column is interpreted as an ipp2p option without the leading "--" (example bit for bit-torrent). If no
PORT is given, ipp2p is assumed.
An entry in this field requires that the PROTO column specify tcp (6), udp (17), ipv6-icmp (58), sctp (132) or udplite (136). Use '-'
if any of the following field is supplied.
SOURCE PORT(S) (sport) - [-|port-name-number-or-range[,port-name-number-or-range]...]
Optional source port(s). If omitted, any source port is acceptable. Specified as a comma-separated list of port names, port numbers or
port ranges.
An entry in this field requires that the PROTO column specify tcp (6), udp (17), sctp (132) or udplite (136). Use '-' if any of the
following fields is supplied.
USER - [!][user-name-or-number][:group-name-or-number]
This optional column may only be non-empty if the SOURCE is the firewall itself.
When this column is non-empty, the rule applies only if the program generating the output is running under the effective user and/or
group specified (or is NOT running under that id if "!" is given).
Examples:
joe
program must be run by joe
:kids
program must be run by a member of the 'kids' group
!:kids
program must not be run by a member of the 'kids' group
TEST - [!]value[/mask][:C]
Optional. Defines a test on the existing packet or connection mark. The rule will match only if the test returns true.
If you don't want to define a test but need to specify anything in the following columns, place a "-" in this field.
!
Inverts the test (not equal)
value
Value of the packet or connection mark.
mask
A mask to be applied to the mark before testing.
:C
Designates a connection mark. If omitted, the packet mark's value is tested.
LENGTH - [length|[min]:[max]]
Optional packet Length. This field, if present allow you to match the length of a packet against a specific value or range of values.
You must have ip6tables length support for this to work. A range is specified in the form min:max where either min or max (but not
both) may be omitted. If min is omitted, then 0 is assumed; if max is omitted, than any packet that is min or longer will match.
TOS (Optional) - tos
Type of service. Either a standard name, or a numeric value to match.
Minimize-Delay (16)
Maximize-Throughput (8)
Maximize-Reliability (4)
Minimize-Cost (2)
Normal-Service (0)
CONNBYTES - [!]min:[max[:{O|R|B}[:{B|P|A}]]]
Optional connection Bytes; defines a byte or packet range that the connection must fall within in order for the rule to match.
A packet matches if the the packet/byte count is within the range defined by min and max (unless ! is given in which case, a packet
matches if the packet/byte count is not within the range). min is an integer which defines the beginning of the byte/packet range.
max is an integer which defines the end of the byte/packet range; if omitted, only the beginning of the range is checked. The first
letter gives the direction which the range refers to:O - The original direction of the connection. .sp R - The opposite direction from
the original connection. .sp B - The total of both directions.
If omitted, B is assumed.
The second letter determines what the range refers to.B - Bytes .sp P - Packets .sp A - Average packet size.If omitted, B is assumed.
HELPER - helper
Optional. Names a Netfiler protocol helper module such as ftp, sip, amanda, etc. A packet will match if it was accepted by the named
helper module. You can also append "-" and a port number to the helper module name (e.g., ftp-21) to specify the port number that the
original connection was made on.
Example: Mark all FTP data connections with mark 4:
#ACTION SOURCE DEST PROTO PORT(S) SOURCE USER TEST LENGTH TOS CONNBYTES HELPER
# PORT(S)
4 ::/0 ::/0 TCP - - - - - - - ftp
HEADERS - [!][any:|exactly:]header-list (Optional - Added in Shorewall 4.4.15)
The header-list consists of a comma-separated list of headers from the following list.
auth, ah, or 51
Authentication Headers extension header.
esp, or 50
Encrypted Security Payload extension header.
hop, hop-by-hop or 0
Hop-by-hop options extension header.
route, ipv6-route or 41
IPv6 Route extension header.
frag, ipv6-frag or 44
IPv6 fragmentation extension header.
none, ipv6-nonxt or 59
No next header
proto, protocol or 255
Any protocol header.
If any: is specified, the rule will match if any of the listed headers are present. If exactly: is specified, the will match packets
that exactly include all specified headers. If neither is given, any: is assumed.
If ! is entered, the rule will match those packets which would not be matched when ! is omitted.
PROBABILITY - [probability]
Added in Shorewall 4.5.0. When non-empty, requires the Statistics Match capability in your kernel and ip6tables and causes the rule to
match randomly but with the given probability. The probability is a number 0 < probability <= 1 and may be expressed at up to 8 decimal
points of precision.
EXAMPLE
Example 1:
Mark all forwarded ICMP echo traffic with packet mark 1. Mark all forwarded peer to peer traffic with packet mark 4.
This is a little more complex than otherwise expected. Since the ipp2p module is unable to determine all packets in a connection are
P2P packets, we mark the entire connection as P2P if any of the packets are determined to match.
We assume packet/connection mark 0 means unclassified.
#ACTION SOURCE DEST PROTO PORT(S) SOURCE USER TEST
# PORT(S)
1 ::/0 ::/0 icmp echo-request
1 ::/0 ::/0 icmp echo-reply
RESTORE ::/0 ::/0 all - - - 0
CONTINUE ::/0 ::/0 all - - - !0
4 ::/0 ::/0 ipp2p:all
SAVE ::/0 ::/0 all - - - !0
If a packet hasn't been classifed (packet mark is 0), copy the connection mark to the packet mark. If the packet mark is set, we're
done. If the packet is P2P, set the packet mark to 4. If the packet mark has been set, save it to the connection mark.
FILES
/etc/shorewall6/tcrules
SEE ALSO
http://shorewall.net/traffic_shaping.htm
http://shorewall.net/MultiISP.html
http://shorewall.net/PacketMarking.html
http://shorewall.net/configuration_file_basics.htm#Pairs
shorewall6(8), shorewall6-accounting(5), shorewall6-actions(5), shorewall6-blacklist(5), shorewall6-ecn(5), shorewall6-exclusion(5),
shorewall6-hosts(5), shorewall6-interfaces(5), shorewall6-maclist(5), shoewall6-netmap(5),shorewall6-params(5), shorewall6-policy(5),
shorewall6-providers(5), shorewall6-rtrules(5), shorewall6-routestopped(5), shorewall6-rules(5), shorewall6.conf(5),
shorewall6-secmarks(5), shorewall6-tcclasses(5), shorewall6-tcdevices(5), shorewall6-tos(5), shorewall6-tunnels(5), shorewall6-zones(5)
NOTES
1. shorewall6-rules
http://www.shorewall.net/manpages6/shorewall6-rules.html
2. shorewall6.conf
http://www.shorewall.net/manpages6/shorewall6.conf.html
3. shorewall6-tcdevices
http://www.shorewall.net/manpages6/shorewall6-tcdevices.html
4. shorewall6-tcclasses
http://www.shorewall.net/manpages6/shorewall6-tcclasses.html
5. shorewall6-providers
http://www.shorewall.net/manpages6/shorewall6-providers.html
6. shorewall6-exclusion
http://www.shorewall.net/manpages6/shorewall6-exclusion.html
[FIXME: source] 06/28/2012 SHOREWALL6-TCRULES(5)