Provided by: ipset_7.5-1ubuntu0.20.04.1_amd64 
NAME
ipset — administration tool for IP sets
SYNOPSIS
ipset [ OPTIONS ] COMMAND [ COMMAND-OPTIONS ]
COMMANDS := { create | add | del | test | destroy | list | save | restore | flush | rename
| swap | help | version | - }
OPTIONS := { -exist | -output { plain | save | xml } | -quiet | -resolve | -sorted | -name
| -terse | -file filename }
ipset create SETNAME TYPENAME [ CREATE-OPTIONS ]
ipset add SETNAME ADD-ENTRY [ ADD-OPTIONS ]
ipset del SETNAME DEL-ENTRY [ DEL-OPTIONS ]
ipset test SETNAME TEST-ENTRY [ TEST-OPTIONS ]
ipset destroy [ SETNAME ]
ipset list [ SETNAME ]
ipset save [ SETNAME ]
ipset restore
ipset flush [ SETNAME ]
ipset rename SETNAME-FROM SETNAME-TO
ipset swap SETNAME-FROM SETNAME-TO
ipset help [ TYPENAME ]
ipset version
ipset -
DESCRIPTION
ipset is used to set up, maintain and inspect so called IP sets in the Linux kernel.
Depending on the type of the set, an IP set may store IP(v4/v6) addresses, (TCP/UDP) port
numbers, IP and MAC address pairs, IP address and port number pairs, etc. See the set type
definitions below.
Iptables matches and targets referring to sets create references, which protect the given
sets in the kernel. A set cannot be destroyed while there is a single reference pointing
to it.
OPTIONS
The options that are recognized by ipset can be divided into several different groups.
COMMANDS
These options specify the desired action to perform. Only one of them can be specified on
the command line unless otherwise specified below. For all the long versions of the
command names, you need to use only enough letters to ensure that ipset can differentiate
it from all other commands. The ipset parser follows the order here when looking for the
shortest match in the long command names.
n, create SETNAME TYPENAME [ CREATE-OPTIONS ]
Create a set identified with setname and specified type. The type may require type
specific options. If the -exist option is specified, ipset ignores the error
otherwise raised when the same set (setname and create parameters are identical)
already exists.
add SETNAME ADD-ENTRY [ ADD-OPTIONS ]
Add a given entry to the set. If the -exist option is specified, ipset ignores if
the entry already added to the set.
del SETNAME DEL-ENTRY [ DEL-OPTIONS ]
Delete an entry from a set. If the -exist option is specified and the entry is not
in the set (maybe already expired), then the command is ignored.
test SETNAME TEST-ENTRY [ TEST-OPTIONS ]
Test whether an entry is in a set or not. Exit status number is zero if the tested
entry is in the set and nonzero if it is missing from the set.
x, destroy [ SETNAME ]
Destroy the specified set or all the sets if none is given.
If the set has got reference(s), nothing is done and no set destroyed.
list [ SETNAME ] [ OPTIONS ]
List the header data and the entries for the specified set, or for all sets if none
is given. The -resolve option can be used to force name lookups (which may be
slow). When the -sorted option is given, the entries are listed/saved sorted (which
may be slow). The option -output can be used to control the format of the listing:
plain, save or xml. (The default is plain.) If the option -name is specified,
just the names of the existing sets are listed. If the option -terse is specified,
just the set names and headers are listed. The output is printed to stdout, the
option -file can be used to specify a filename instead of stdout.
save [ SETNAME ]
Save the given set, or all sets if none is given to stdout in a format that restore
can read. The option -file can be used to specify a filename instead of stdout.
restore
Restore a saved session generated by save. The saved session can be fed from stdin
or the option -file can be used to specify a filename instead of stdin.
Please note, existing sets and elements are not erased by restore unless specified
so in the restore file. All commands are allowed in restore mode except list, help,
version, interactive mode and restore itself.
flush [ SETNAME ]
Flush all entries from the specified set or flush all sets if none is given.
e, rename SETNAME-FROM SETNAME-TO
Rename a set. Set identified by SETNAME-TO must not exist.
w, swap SETNAME-FROM SETNAME-TO
Swap the content of two sets, or in another words, exchange the name of two sets.
The referred sets must exist and compatible type of sets can be swapped only.
help [ TYPENAME ]
Print help and set type specific help if TYPENAME is specified.
version
Print program version.
- If a dash is specified as command, then ipset enters a simple interactive mode and
the commands are read from the standard input. The interactive mode can be
finished by entering the pseudo-command quit.
OTHER OPTIONS
The following additional options can be specified. The long option names cannot be
abbreviated.
-!, -exist
Ignore errors when exactly the same set is to be created or already added entry is
added or missing entry is deleted.
-o, -output { plain | save | xml }
Select the output format to the list command.
-q, -quiet
Suppress any output to stdout and stderr. ipset will still exit with error if it
cannot continue.
-r, -resolve
When listing sets, enforce name lookup. The program will try to display the IP
entries resolved to host names which requires slow DNS lookups.
-s, -sorted
Sorted output. When listing or saving sets, the entries are listed sorted.
-n, -name
List just the names of the existing sets, i.e. suppress listing of set headers and
members.
-t, -terse
List the set names and headers, i.e. suppress listing of set members.
-f, -file filename
Specify a filename to print into instead of stdout (list or save commands) or read
from instead of stdin (restore command).
INTRODUCTION
A set type comprises of the storage method by which the data is stored and the data
type(s) which are stored in the set. Therefore the TYPENAME parameter of the create
command follows the syntax
TYPENAME := method:datatype[,datatype[,datatype]]
where the current list of the methods are bitmap, hash, and list and the possible data
types are ip, net, mac, port and iface. The dimension of a set is equal to the number of
data types in its type name.
When adding, deleting or testing entries in a set, the same comma separated data syntax
must be used for the entry parameter of the commands, i.e
ipset add foo ipaddr,portnum,ipaddr
If host names or service names with dash in the name are used instead of IP addresses or
service numbers, then the host name or service name must be enclosed in square brackets.
Example:
ipset add foo [test-hostname],[ftp-data]
In the case of host names the DNS resolver is called internally by ipset but if it returns
multiple IP addresses, only the first one is used.
The bitmap and list types use a fixed sized storage. The hash types use a hash to store
the elements. In order to avoid clashes in the hash, a limited number of chaining, and if
that is exhausted, the doubling of the hash size is performed when adding entries by the
ipset command. When entries added by the SET target of iptables/ip6tables, then the hash
size is fixed and the set won't be duplicated, even if the new entry cannot be added to
the set.
GENERIC CREATE AND ADD OPTIONS
timeout
All set types supports the optional timeout parameter when creating a set and adding
entries. The value of the timeout parameter for the create command means the default
timeout value (in seconds) for new entries. If a set is created with timeout support, then
the same timeout option can be used to specify non-default timeout values when adding
entries. Zero timeout value means the entry is added permanent to the set. The timeout
value of already added elements can be changed by re-adding the element using the -exist
option. The largest possible timeout value is 2147483 (in seconds). Example:
ipset create test hash:ip timeout 300
ipset add test 192.168.0.1 timeout 60
ipset -exist add test 192.168.0.1 timeout 600
When listing the set, the number of entries printed in the header might be larger than the
listed number of entries for sets with the timeout extensions: the number of entries in
the set is updated when elements added/deleted to the set and periodically when the
garbage collector evicts the timed out entries.
counters, packets, bytes
All set types support the optional counters option when creating a set. If the option is
specified then the set is created with packet and byte counters per element support. The
packet and byte counters are initialized to zero when the elements are (re-)added to the
set, unless the packet and byte counter values are explicitly specified by the packets and
bytes options. An example when an element is added to a set with non-zero counter values:
ipset create foo hash:ip counters
ipset add foo 192.168.1.1 packets 42 bytes 1024
comment
All set types support the optional comment extension. Enabling this extension on an ipset
enables you to annotate an ipset entry with an arbitrary string. This string is completely
ignored by both the kernel and ipset itself and is purely for providing a convenient means
to document the reason for an entry's existence. Comments must not contain any quotation
marks and the usual escape character (\) has no meaning. For example, the following shell
command is illegal:
ipset add foo 1.1.1.1 comment "this comment is \"bad\""
In the above, your shell will of course escape the quotation marks and ipset will see the
quote marks in the argument for the comment, which will result in a parse error. If you
are writing your own system, you should avoid creating comments containing a quotation
mark if you do not want to break "ipset save" and "ipset restore", nonetheless, the kernel
will not stop you from doing so. The following is perfectly acceptable:
ipset create foo hash:ip comment
ipset add foo 192.168.1.1/24 comment "allow access to SMB share on \\\\fileserv\\"
the above would appear as: "allow access to SMB share on \\fileserv\"
skbinfo, skbmark, skbprio, skbqueue
All set types support the optional skbinfo extension. This extension allows you to store
the metainfo (firewall mark, tc class and hardware queue) with every entry and map it to
packets by usage of SET netfilter target with --map-set option. skbmark option format:
MARK or MARK/MASK, where MARK and MASK are 32bit hex numbers with 0x prefix. If only mark
is specified mask 0xffffffff are used. skbprio option has tc class format: MAJOR:MINOR,
where major and minor numbers are hex without 0x prefix. skbqueue option is just decimal
number.
ipset create foo hash:ip skbinfo
ipset add foo skbmark 0x1111/0xff00ffff skbprio 1:10 skbqueue 10
hashsize
This parameter is valid for the create command of all hash type sets. It defines the
initial hash size for the set, default is 1024. The hash size must be a power of two, the
kernel automatically rounds up non power of two hash sizes to the first correct value.
Example:
ipset create test hash:ip hashsize 1536
maxelem
This parameter is valid for the create command of all hash type sets. It does define the
maximal number of elements which can be stored in the set, default 65536. Example:
ipset create test hash:ip maxelem 2048.
family { inet | inet6 }
This parameter is valid for the create command of all hash type sets except for hash:mac.
It defines the protocol family of the IP addresses to be stored in the set. The default is
inet, i.e IPv4. For the inet family one can add or delete multiple entries by specifying
a range or a network of IPv4 addresses in the IP address part of the entry:
ipaddr := { ip | fromaddr-toaddr | ip/cidr }
netaddr := { fromaddr-toaddr | ip/cidr }
Example:
ipset create test hash:ip family inet6
nomatch
The hash set types which can store net type of data (i.e. hash:*net*) support the optional
nomatch option when adding entries. When matching elements in the set, entries marked as
nomatch are skipped as if those were not added to the set, which makes possible to build
up sets with exceptions. See the example at hash type hash:net below.
When elements are tested by ipset, the nomatch flags are taken into account. If one wants
to test the existence of an element marked with nomatch in a set, then the flag must be
specified too.
forceadd
All hash set types support the optional forceadd parameter when creating a set. When sets
created with this option become full the next addition to the set may succeed and evict a
random entry from the set.
ipset create foo hash:ip forceadd
wildcard
This flag is valid when adding elements to a hash:net,iface set. If the flag is set, then
prefix matching is used when comparing with this element. For example, an element
containing the interface name "eth" will match any name with that prefix.
SET TYPES
bitmap:ip
The bitmap:ip set type uses a memory range to store either IPv4 host (default) or IPv4
network addresses. A bitmap:ip type of set can store up to 65536 entries.
CREATE-OPTIONS := range fromip-toip|ip/cidr [ netmask cidr ] [ timeout value ] [ counters
] [ comment ] [ skbinfo ]
ADD-ENTRY := { ip | fromip-toip | ip/cidr }
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := { ip | fromip-toip | ip/cidr }
TEST-ENTRY := ip
Mandatory create options:
range fromip-toip|ip/cidr
Create the set from the specified inclusive address range expressed in an IPv4
address range or network. The size of the range (in entries) cannot exceed the
limit of maximum 65536 elements.
Optional create options:
netmask cidr
When the optional netmask parameter specified, network addresses will be stored in
the set instead of IP host addresses. The cidr prefix value must be between 1-32.
An IP address will be in the set if the network address, which is resulted by
masking the address with the specified netmask, can be found in the set.
The bitmap:ip type supports adding or deleting multiple entries in one command.
Examples:
ipset create foo bitmap:ip range 192.168.0.0/16
ipset add foo 192.168.1/24
ipset test foo 192.168.1.1
bitmap:ip,mac
The bitmap:ip,mac set type uses a memory range to store IPv4 and a MAC address pairs. A
bitmap:ip,mac type of set can store up to 65536 entries.
CREATE-OPTIONS := range fromip-toip|ip/cidr [ timeout value ] [ counters ] [ comment ] [
skbinfo ]
ADD-ENTRY := ip[,macaddr]
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := ip[,macaddr]
TEST-ENTRY := ip[,macaddr]
Mandatory options to use when creating a bitmap:ip,mac type of set:
range fromip-toip|ip/cidr
Create the set from the specified inclusive address range expressed in an IPv4
address range or network. The size of the range cannot exceed the limit of maximum
65536 entries.
The bitmap:ip,mac type is exceptional in the sense that the MAC part can be left out when
adding/deleting/testing entries in the set. If we add an entry without the MAC address
specified, then when the first time the entry is matched by the kernel, it will
automatically fill out the missing MAC address with the MAC address from the packet. The
source MAC address is used if the entry matched due to a src parameter of the set match,
and the destination MAC address is used if available and the entry matched due to a dst
parameter. If the entry was specified with a timeout value, the timer starts off when the
IP and MAC address pair is complete.
The bitmap:ip,mac type of sets require two src/dst parameters of the set match and SET
target netfilter kernel modules. For matches on destination MAC addresses, see COMMENTS
below.
Examples:
ipset create foo bitmap:ip,mac range 192.168.0.0/16
ipset add foo 192.168.1.1,12:34:56:78:9A:BC
ipset test foo 192.168.1.1
bitmap:port
The bitmap:port set type uses a memory range to store port numbers and such a set can
store up to 65536 ports.
CREATE-OPTIONS := range fromport-toport [ timeout value ] [ counters ] [ comment ] [
skbinfo ]
ADD-ENTRY := { [proto:]port | [proto:]fromport-toport }
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := { [proto:]port | [proto:]fromport-toport }
TEST-ENTRY := [proto:]port
Mandatory options to use when creating a bitmap:port type of set:
range [proto:]fromport-toport
Create the set from the specified inclusive port range.
The set match and SET target netfilter kernel modules interpret the stored numbers as TCP
or UDP port numbers.
proto only needs to be specified if a service name is used and that name does not exist as
a TCP service. The protocol is never stored in the set, just the port number of the
service.
Examples:
ipset create foo bitmap:port range 0-1024
ipset add foo 80
ipset test foo 80
ipset del foo udp:[macon-udp]-[tn-tl-w2]
hash:ip
The hash:ip set type uses a hash to store IP host addresses (default) or network
addresses. Zero valued IP address cannot be stored in a hash:ip type of set.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
netmask cidr ] [ timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := ipaddr
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := ipaddr
TEST-ENTRY := ipaddr
Optional create options:
netmask cidr
When the optional netmask parameter specified, network addresses will be stored in
the set instead of IP host addresses. The cidr prefix value must be between 1-32
for IPv4 and between 1-128 for IPv6. An IP address will be in the set if the
network address, which is resulted by masking the address with the netmask, can be
found in the set. Examples:
ipset create foo hash:ip netmask 30
ipset add foo 192.168.1.0/24
ipset test foo 192.168.1.2
hash:mac
The hash:mac set type uses a hash to store MAC addresses. Zero valued MAC addresses cannot
be stored in a hash:mac type of set. For matches on destination MAC addresses, see
COMMENTS below.
CREATE-OPTIONS := [ hashsize value ] [ maxelem value ] [ timeout value ] [ counters ] [
comment ] [ skbinfo ]
ADD-ENTRY := macaddr
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := macaddr
TEST-ENTRY := macaddr
Examples:
ipset create foo hash:mac
ipset add foo 01:02:03:04:05:06
ipset test foo 01:02:03:04:05:06
hash:ip,mac
The hash:ip,mac set type uses a hash to store IP and a MAC address pairs. Zero valued MAC
addresses cannot be stored in a hash:ip,mac type of set. For matches on destination MAC
addresses, see COMMENTS below.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := ipaddr,macaddr
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := ipaddr,macaddr
TEST-ENTRY := ipaddr,macaddr
Examples:
ipset create foo hash:ip,mac
ipset add foo 1.1.1.1,01:02:03:04:05:06
ipset test foo 1.1.1.1,01:02:03:04:05:06
hash:net
The hash:net set type uses a hash to store different sized IP network addresses. Network
address with zero prefix size cannot be stored in this type of sets.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := netaddr
ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] [ comment
string ] [ skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := netaddr
TEST-ENTRY := netaddr
where netaddr := ip[/cidr]
When adding/deleting/testing entries, if the cidr prefix parameter is not specified, then
the host prefix value is assumed. When adding/deleting entries, the exact element is
added/deleted and overlapping elements are not checked by the kernel. When testing
entries, if a host address is tested, then the kernel tries to match the host address in
the networks added to the set and reports the result accordingly.
From the set netfilter match point of view the searching for a match always starts from
the smallest size of netblock (most specific prefix) to the largest one (least specific
prefix) added to the set. When adding/deleting IP addresses to the set by the SET
netfilter target, it will be added/deleted by the most specific prefix which can be
found in the set, or by the host prefix value if the set is empty.
The lookup time grows linearly with the number of the different prefix values added to the
set.
Example:
ipset create foo hash:net
ipset add foo 192.168.0.0/24
ipset add foo 10.1.0.0/16
ipset add foo 192.168.0/24
ipset add foo 192.168.0/30 nomatch
When matching the elements in the set above, all IP addresses will match from the networks
192.168.0.0/24, 10.1.0.0/16 and 192.168.0/24 except the ones from 192.168.0/30.
hash:net,net
The hash:net,net set type uses a hash to store pairs of different sized IP network
addresses. Bear in mind that the first parameter has precedence over the second, so
a nomatch entry could be potentially be ineffective if a more specific first parameter
existed with a suitable second parameter. Network address with zero prefix size cannot be
stored in this type of set.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := netaddr,netaddr
ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] [ comment
string ] [ skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := netaddr,netaddr
TEST-ENTRY := netaddr,netaddr
where netaddr := ip[/cidr]
When adding/deleting/testing entries, if the cidr prefix parameter is not specified, then
the host prefix value is assumed. When adding/deleting entries, the exact element is
added/deleted and overlapping elements are not checked by the kernel. When testing
entries, if a host address is tested, then the kernel tries to match the host address in
the networks added to the set and reports the result accordingly.
From the set netfilter match point of view the searching for a match always starts from
the smallest size of netblock (most specific prefix) to the largest one (least specific
prefix) with the first param having precedence. When adding/deleting IP addresses to
the set by the SET netfilter target, it will be added/deleted by the most specific
prefix which can be found in the set, or by the host prefix value if the set is empty.
The lookup time grows linearly with the number of the different prefix values added to the
first parameter of the set. The number of secondary prefixes further increases this as the
list of secondary prefixes is traversed per primary prefix.
Example:
ipset create foo hash:net,net
ipset add foo 192.168.0.0/24,10.0.1.0/24
ipset add foo 10.1.0.0/16,10.255.0.0/24
ipset add foo 192.168.0/24,192.168.54.0-192.168.54.255
ipset add foo 192.168.0/30,192.168.64/30 nomatch
When matching the elements in the set above, all IP addresses will match from the networks
192.168.0.0/24<->10.0.1.0/24, 10.1.0.0/16<->10.255.0.0/24 and
192.168.0/24<->192.168.54.0/24 except the ones from 192.168.0/30<->192.168.64/30.
hash:ip,port
The hash:ip,port set type uses a hash to store IP address and port number pairs. The port
number is interpreted together with a protocol (default TCP) and zero protocol number
cannot be used.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := ipaddr,[proto:]port
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := ipaddr,[proto:]port
TEST-ENTRY := ipaddr,[proto:]port
The [proto:]port part of the elements may be expressed in the following forms, where the
range variations are valid when adding or deleting entries:
portname[-portname]
TCP port or range of ports expressed in TCP portname identifiers from /etc/services
portnumber[-portnumber]
TCP port or range of ports expressed in TCP port numbers
tcp|sctp|udp|udplite:portname|portnumber[-portname|portnumber]
TCP, SCTP, UDP or UDPLITE port or port range expressed in port name(s) or port
number(s)
icmp:codename|type/code
ICMP codename or type/code. The supported ICMP codename identifiers can always be
listed by the help command.
icmpv6:codename|type/code
ICMPv6 codename or type/code. The supported ICMPv6 codename identifiers can always
be listed by the help command.
proto:0
All other protocols, as an identifier from /etc/protocols or number. The pseudo
port number must be zero.
The hash:ip,port type of sets require two src/dst parameters of the set match and SET
target kernel modules.
Examples:
ipset create foo hash:ip,port
ipset add foo 192.168.1.0/24,80-82
ipset add foo 192.168.1.1,udp:53
ipset add foo 192.168.1.1,vrrp:0
ipset test foo 192.168.1.1,80
hash:net,port
The hash:net,port set type uses a hash to store different sized IP network address and
port pairs. The port number is interpreted together with a protocol (default TCP) and zero
protocol number cannot be used. Network address with zero prefix size is not accepted
either.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := netaddr,[proto:]port
ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] [ comment
string ] [ skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := netaddr,[proto:]port
TEST-ENTRY := netaddr,[proto:]port
where netaddr := ip[/cidr]
For the netaddr part of the elements see the description at the hash:net set type. For the
[proto:]port part of the elements see the description at the hash:ip,port set type.
When adding/deleting/testing entries, if the cidr prefix parameter is not specified, then
the host prefix value is assumed. When adding/deleting entries, the exact element is
added/deleted and overlapping elements are not checked by the kernel. When testing
entries, if a host address is tested, then the kernel tries to match the host address in
the networks added to the set and reports the result accordingly.
From the set netfilter match point of view the searching for a match always starts from
the smallest size of netblock (most specific prefix) to the largest one (least specific
prefix) added to the set. When adding/deleting IP addresses to the set by the SET
netfilter target, it will be added/deleted by the most specific prefix which can be
found in the set, or by the host prefix value if the set is empty.
The lookup time grows linearly with the number of the different prefix values added to the
set.
Examples:
ipset create foo hash:net,port
ipset add foo 192.168.0/24,25
ipset add foo 10.1.0.0/16,80
ipset test foo 192.168.0/24,25
hash:ip,port,ip
The hash:ip,port,ip set type uses a hash to store IP address, port number and a second IP
address triples. The port number is interpreted together with a protocol (default TCP) and
zero protocol number cannot be used.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := ipaddr,[proto:]port,ip
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := ipaddr,[proto:]port,ip
TEST-ENTRY := ipaddr,[proto:]port,ip
For the first ipaddr and [proto:]port parts of the elements see the descriptions at the
hash:ip,port set type.
The hash:ip,port,ip type of sets require three src/dst parameters of the set match and SET
target kernel modules.
Examples:
ipset create foo hash:ip,port,ip
ipset add foo 192.168.1.1,80,10.0.0.1
ipset test foo 192.168.1.1,udp:53,10.0.0.1
hash:ip,port,net
The hash:ip,port,net set type uses a hash to store IP address, port number and IP network
address triples. The port number is interpreted together with a protocol (default TCP) and
zero protocol number cannot be used. Network address with zero prefix size cannot be
stored either.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := ipaddr,[proto:]port,netaddr
ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] [ comment
string ] [ skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := ipaddr,[proto:]port,netaddr
TEST-ENTRY := ipaddr,[proto:]port,netaddr
where netaddr := ip[/cidr]
For the ipaddr and [proto:]port parts of the elements see the descriptions at the
hash:ip,port set type. For the netaddr part of the elements see the description at the
hash:net set type.
From the set netfilter match point of view the searching for a match always starts from
the smallest size of netblock (most specific cidr) to the largest one (least specific
cidr) added to the set. When adding/deleting triples to the set by the SET netfilter
target, it will be added/deleted by the most specific cidr which can be found in the
set, or by the host cidr value if the set is empty.
The lookup time grows linearly with the number of the different cidr values added to the
set.
The hash:ip,port,net type of sets require three src/dst parameters of the set match and
SET target kernel modules.
Examples:
ipset create foo hash:ip,port,net
ipset add foo 192.168.1,80,10.0.0/24
ipset add foo 192.168.2,25,10.1.0.0/16
ipset test foo 192.168.1,80.10.0.0/24
hash:ip,mark
The hash:ip,mark set type uses a hash to store IP address and packet mark pairs.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ markmask value ] [ hashsize value ] [
maxelem value ] [ timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := ipaddr,mark
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := ipaddr,mark
TEST-ENTRY := ipaddr,mark
Optional create options:
markmask value
Allows you to set bits you are interested in the packet mark. This values is then
used to perform bitwise AND operation for every mark added. markmask can be any
value between 1 and 4294967295, by default all 32 bits are set.
The mark can be any value between 0 and 4294967295.
The hash:ip,mark type of sets require two src/dst parameters of the set match and SET
target kernel modules.
Examples:
ipset create foo hash:ip,mark
ipset add foo 192.168.1.0/24,555
ipset add foo 192.168.1.1,0x63
ipset add foo 192.168.1.1,111236
hash:net,port,net
The hash:net,port,net set type behaves similarly to hash:ip,port,net but accepts a cidr
value for both the first and last parameter. Either subnet is permitted to be a /0 should
you wish to match port between all destinations.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := netaddr,[proto:]port,netaddr
ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] [ comment
string ] [ skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := netaddr,[proto:]port,netaddr
TEST-ENTRY := netaddr,[proto:]port,netaddr
where netaddr := ip[/cidr]
For the [proto:]port part of the elements see the description at the hash:ip,port set
type. For the netaddr part of the elements see the description at the hash:net set type.
From the set netfilter match point of view the searching for a match always starts from
the smallest size of netblock (most specific cidr) to the largest one (least specific
cidr) added to the set. When adding/deleting triples to the set by the SET netfilter
target, it will be added/deleted by the most specific cidr which can be found in the
set, or by the host cidr value if the set is empty. The first subnet has precedence when
performing the most-specific lookup, just as for hash:net,net
The lookup time grows linearly with the number of the different cidr values added to the
set and by the number of secondary cidr values per primary.
The hash:net,port,net type of sets require three src/dst parameters of the set match and
SET target kernel modules.
Examples:
ipset create foo hash:net,port,net
ipset add foo 192.168.1.0/24,0,10.0.0/24
ipset add foo 192.168.2.0/24,25,10.1.0.0/16
ipset test foo 192.168.1.1,80,10.0.0.1
hash:net,iface
The hash:net,iface set type uses a hash to store different sized IP network address and
interface name pairs.
CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [
timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := netaddr,[physdev:]iface
ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] [ comment
string ] [ skbmark value ] [ skbprio value ] [ skbqueue value ] [ wildcard ]
DEL-ENTRY := netaddr,[physdev:]iface
TEST-ENTRY := netaddr,[physdev:]iface
where netaddr := ip[/cidr]
For the netaddr part of the elements see the description at the hash:net set type.
When adding/deleting/testing entries, if the cidr prefix parameter is not specified, then
the host prefix value is assumed. When adding/deleting entries, the exact element is
added/deleted and overlapping elements are not checked by the kernel. When testing
entries, if a host address is tested, then the kernel tries to match the host address in
the networks added to the set and reports the result accordingly.
From the set netfilter match point of view the searching for a match always starts from
the smallest size of netblock (most specific prefix) to the largest one (least specific
prefix) added to the set. When adding/deleting IP addresses to the set by the SET
netfilter target, it will be added/deleted by the most specific prefix which can be
found in the set, or by the host prefix value if the set is empty.
The second direction parameter of the set match and SET target modules corresponds to the
incoming/outgoing interface: src to the incoming one (similar to the -i flag of iptables),
while dst to the outgoing one (similar to the -o flag of iptables). When the interface is
flagged with physdev:, the interface is interpreted as the incoming/outgoing bridge port.
The lookup time grows linearly with the number of the different prefix values added to the
set.
The internal restriction of the hash:net,iface set type is that the same network prefix
cannot be stored with more than 64 different interfaces in a single set.
Examples:
ipset create foo hash:net,iface
ipset add foo 192.168.0/24,eth0
ipset add foo 10.1.0.0/16,eth1
ipset test foo 192.168.0/24,eth0
list:set
The list:set type uses a simple list in which you can store set names.
CREATE-OPTIONS := [ size value ] [ timeout value ] [ counters ] [ comment ] [ skbinfo ]
ADD-ENTRY := setname [ { before | after } setname ]
ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] [ comment string ] [
skbmark value ] [ skbprio value ] [ skbqueue value ]
DEL-ENTRY := setname [ { before | after } setname ]
TEST-ENTRY := setname [ { before | after } setname ]
Optional create options:
size value
The size of the list, the default is 8. The parameter is ignored since ipset
version 6.24.
By the ipset command you can add, delete and test set names in a list:set type of set.
By the set match or SET target of netfilter you can test, add or delete entries in the
sets added to the list:set type of set. The match will try to find a matching entry in the
sets and the target will try to add an entry to the first set to which it can be added.
The number of direction options of the match and target are important: sets which require
more parameters than specified are skipped, while sets with equal or less parameters are
checked, elements added/deleted. For example if a and b are list:set type of sets then in
the command
iptables -m set --match-set a src,dst -j SET --add-set b src,dst
the match and target will skip any set in a and b which stores data triples, but will
match all sets with single or double data storage in a set and stop matching at the first
successful set, and add src to the first single or src,dst to the first double data
storage set in b to which the entry can be added. You can imagine a list:set type of set
as an ordered union of the set elements.
Please note: by the ipset command you can add, delete and test the setnames in a list:set
type of set, and not the presence of a set's member (such as an IP address).
GENERAL RESTRICTIONS
Zero valued set entries cannot be used with hash methods. Zero protocol value with ports
cannot be used.
COMMENTS
If you want to store same size subnets from a given network (say /24 blocks from a /8
network), use the bitmap:ip set type. If you want to store random same size networks (say
random /24 blocks), use the hash:ip set type. If you have got random size of netblocks,
use hash:net.
Matching on destination MAC addresses using the dst parameter of the set match netfilter
kernel modules will only work if the destination MAC address is available in the packet at
the given processing stage, that is, it only applies for incoming packets in the
PREROUTING, INPUT and FORWARD chains, against the MAC address as originally found in the
received packet (typically, one of the MAC addresses of the local host). This is not the
destination MAC address a destination IP address resolves to, after routing. If the MAC
address is not available (e.g. in the OUTPUT chain), the packet will simply not match.
Backward compatibility is maintained and old ipset syntax is still supported.
The iptree and iptreemap set types are removed: if you refer to them, they are
automatically replaced by hash:ip type of sets.
DIAGNOSTICS
Various error messages are printed to standard error. The exit code is 0 for correct
functioning.
BUGS
Bugs? No, just funny features. :-) OK, just kidding...
SEE ALSO
iptables(8), ip6tables(8) iptables-extensions(8)
AUTHORS
Jozsef Kadlecsik wrote ipset, which is based on ippool by Joakim Axelsson, Patrick Schaaf
and Martin Josefsson.
Sven Wegener wrote the iptreemap type.
LAST REMARK
I stand on the shoulders of giants.