IPSET(8) IPSET(8) 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. added to (already expired from) the set. test SETNAME TEST-ENTRY [ TEST-OPTIONS ] Test wether 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 sorted (if the given set type supports the operation). 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 identical 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. 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 sets entries are listed sorted. Not supported yet. -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 ipta‐ bles/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 readding the element using the -exist option. Example: ipset create test hash:ip timeout 300 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 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 ] ADD-ENTRY := { ip | fromip-toip | ip/cidr } ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes 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 net‐ work. 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. range fromip-toip|ip/cidr Create the set from the specified inclusive address range expressed in an IPv4 address range or net‐ work. 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/delet‐ ing/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 source MAC address from the packet. 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 and the second one must be src to match, add or delete entries, because the set match and SET target have access to the source MAC address only. 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 ] ADD-ENTRY := { port | fromport-toport } ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] DEL-ENTRY := { port | fromport-toport } TEST-ENTRY := port Mandatory options to use when creating a bitmap:port type of set: range 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. Examples: ipset create foo bitmap:port range 0-1024 ipset add foo 80 ipset test foo 80 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. Optional create options: family { inet | inet6 } The protocol family of the IP addresses to be stored in the set. The default is inet, i.e IPv4. hashsize value 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. maxelem value The maximal number of elements which can be stored in the set, default 65536. 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. For the inet family one can add or delete multiple entries by specifying a range or a network: ipaddr := { ip | fromaddr-toaddr | ip/cidr } Examples: ipset create foo hash:ip netmask 30 ipset add foo 192.168.1.0/24 ipset test foo 192.168.1.2 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 ] [ coun‐ ters ] ADD-ENTRY := netaddr ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] DEL-ENTRY := netaddr TEST-ENTRY := netaddr where netaddr := ip[/cidr] Optional create options: family { inet | inet6 } The protocol family of the IP addresses to be stored in the set. The default is inet, i.e IPv4. hashsize value The initial hash size for the set, default is 1024. The hash size must be a power of two, the kernel 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:ip,port The hash:ip,port set type uses a hash to store IP address and port number pairs. The port number is inter‐ preted together with a protocol (default TCP) and zero protocol number cannot be used. CREATE-OPTIONS := [ family { inet | inet6 } ] | [ hashsize value ] [ maxelem value ] [ timeout value ] [ coun‐ ters ] ADD-ENTRY := ipaddr,[proto:]port ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] DEL-ENTRY := ipaddr,[proto:]port TEST-ENTRY := ipaddr,[proto:]port Optional create options: family { inet | inet6 } The protocol family of the IP addresses to be stored in the set. The default is inet, i.e IPv4. hashsize value 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 maxelem value The maximal number of elements which can be stored in the set, default 65536. 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: 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 ] [ coun‐ ters ] ADD-ENTRY := netaddr,[proto:]port ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] DEL-ENTRY := netaddr,[proto:]port TEST-ENTRY := netaddr,[proto:]port where netaddr := ip[/cidr] Optional create options: family { inet | inet6 } The protocol family of the IP addresses to be stored in the set. The default is inet, i.e IPv4. hashsize value The initial hash size for the set, default is 1024. The hash size must be a power of two, the kernel 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 ] [ coun‐ ters ] ADD-ENTRY := ipaddr,[proto:]port,ip ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes 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. Optional create options: family { inet | inet6 } The protocol family of the IP addresses to be stored in the set. The default is inet, i.e IPv4. hashsize value 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. maxelem value The maximal number of elements which can be stored in the set, default 65536. The hash:ip,port,ip type of sets require three src/dst parameters of the set match and SET target kernel mod‐ ules. Examples: ipset create foo hash:ip,port,ip ADD-ENTRY := ipaddr,[proto:]port,netaddr ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes 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. Optional create options: family { inet | inet6 } The protocol family of the IP addresses to be stored in the set. The default is inet, i.e IPv4. hashsize value 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. maxelem value The maximal number of elements which can be stored in the set, default 65536. 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 spe‐ cific 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 mod‐ ules. 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: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 ] [ coun‐ ters ] ADD-ENTRY := netaddr,[physdev:]iface ADD-OPTIONS := [ timeout value ] [ nomatch ] [ packets value ] [ bytes value ] hashsize value 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. maxelem value The maximal number of elements which can be stored in the set, default 65536. 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 (simi‐ lar 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 ] ADD-ENTRY := setname [ { before | after } setname ] ADD-OPTIONS := [ timeout value ] [ packets value ] [ bytes value ] DEL-ENTRY := setname [ { before | after } setname ] TEST-ENTRY := setname [ { before | after } setname ] Optional create options: 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 sin‐ gle 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 bit‐ map: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. 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) AUTHORS Jozsef Kadlecsik wrote ipset, which is based on ippool by Joakim Axelsson, Patrick Schaaf and Martin Josefs‐ son. Sven Wegener wrote the iptreemap type. LAST REMARK I stand on the shoulders of giants. Jozsef Kadlecsik Apr 4, 2013 IPSET(8)