Name
tcfilters — Shorewall u32/basic classifier rules file
Synopsis
/etc/shorewall[6]/tcfilters
Description
Entries in this file cause packets to be classified for traffic shaping.
Beginning with Shorewall 4.4.15, the file may contain entries for both IPv4 and IPv6. By default, all rules apply to IPv4 but that can be changed by inserting a line as follows:
- IPV4
Following entries apply to IPv4.
- IPV6
Following entries apply to IPv6
- ALL
Following entries apply to both IPv4 and IPv6. Each entry is processed twice; once for IPv4 and once for IPv6.
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).
- CLASS - interface:class
The name or number of an interface defined in shorewall-tcdevices(5) followed by a
classnumber defined for that interface in shorewall-tcclasses(5).- SOURCE - {-|address|+
ipset} Source of the packet. May be a host or network
address. DNS names are not allowed. Beginning with Shorewall 4.6.0, an ipset name (prefixed with '+') may be used if your kernel and ip6tables have the Basic Ematch capability and you set BASIC_FILTERS=Yes in shorewall.conf (5). The ipset name may optionally be followed by a number or a comma separated list of src and/or dst enclosed in square brackets ([...]). See shorewall-ipsets(5) for details.- DEST - {-|address|+
ipset} Destination of the packet. May be a host or network
address. DNS names are not allowed. Beginning with Shorewall 4.6.0, an ipset name (prefixed with '+') may be used if your kernel and ip6tables have the Basic Ematch capability and you set BASIC_FILTERS=Yes in shorewall.conf (5). The ipset name may optionally be followed by a number or a comma separated list of src and/or dst enclosed in square brackets ([...]). See shorewall-ipsets(5) for details.You may exclude certain hosts from the set already defined through use of an exclusion (see shorewall-exclusion(5)).
- PROTO - {-|{protocol-number|protocol-name|all}[,...]}
Protocol.
Beginning with Shorewall 4.5.12, this column can accept a comma-separated list of protocols.
- DPORT - [-|port-name-or-number]
Optional destination Ports. A Port name (from services(5)) or a port number; if the protocol is icmp, this column is interpreted as the destination icmp-type(s).
This column was previously labelled DEST PORT(S).
- SPORT - [-|port-name-or-number]
Optional source port.
This column was previously labelled SOURCE PORT(S).
- TOS (Optional) - [-|tos]
Specifies the value of the TOS field. The
tosvalue can be any of the following:tos-minimize-delaytos-maximize-throughputtos-maximize-reliabilitytos-minimize-costtos-normal-servicehex-numberhex-number/hex-number
The
hex-numbers must be exactly two digits (e.g., 0x04)x.- LENGTH - [-|number]
Optional - Must be a power of 2 between 32 and 8192 inclusive. Packets with a total length that is strictly less than the specified
numberwill match the rule.- PRIORITY - [-|priority]
Added in Shorewall 4.5.8. Specifies the rule
priority. Thepriorityvalue must be > 0 and <= 65535.When a
priorityis not given:For Shorewall versions prior to 4.5.8 - all filters have priority 10.
For Shorewall 4.5.8 and later - for each device, the compiler maintains a high-water priority with an initial value of 0. When a filter has no
priority, the high-water priority is incremented by 1 and assigned to the filter. When aprioritygreater than the high-water priority is entered in this column, the high-water priority is set to the specifiedpriority. An attempt to assign a priority value greater than 65535 (explicitly or implicitly) raises an error.
The default priority values used by other Shorewall-generated filters are as follows:
Classify by packet mark - (
class priority<< 8 ) | 20.Ingress policing - 10
Simple TC ACK packets - 1
Complex TC ACK packets - (
class priority<< 8 ) | 10.Classify by TOS - (
class priority<< 8 ) | 15.Class with 'occurs' - 65535
Example
- IPv4 Example 1:
Place all 'ping' traffic on interface 1 in class 10. Note that ALL cannot be used because IPv4 ICMP and IPv6 ICMP are two different protocols.
#CLASS SOURCE DEST PROTO DPORT IPV4 1:10 0.0.0.0/0 0.0.0.0/0 icmp echo-request 1:10 0.0.0.0/0 0.0.0.0/0 icmp echo-reply IPV6 1:10 ::/0 ::/0 icmp6 echo-request 1:10 ::/0 ::/0 icmp6 echo-reply- IPv4 Example 2:
Add two filters with priority 10 (Shorewall 4.5.8 or later).
#CLASS SOURCE DEST PROTO DPORT PRIORITY IPV4 1:10 0.0.0.0/0 0.0.0.0/0 icmp echo-request 10 1:10 0.0.0.0/0 0.0.0.0/0 icmp echo-reply 10- IPv6 Example 1:
Add two filters with priority 10 (Shorewall 4.5.8 or later).
#CLASS SOURCE DEST PROTO DPORT PRIORITY IPV6 1:10 ::/0 ::/0 icmp echo-request 10 1:10 ::/0 ::/0 icmp echo-reply 10
