accounting — Shorewall Accounting file
/etc/shorewall[6]/accounting
Accounting rules exist simply to count packets and bytes in categories that you define in this file. You may display these rules and their packet and byte counters using the shorewall show accounting command.
Beginning with Shorewall 4.4.18, the accounting structure can be created with three root chains:
accountin: Rules that are valid in the INPUT chain (may not specify an output interface).
accountout: Rules that are valid in the OUTPUT chain (may not specify an input interface or a MAC address).
accounting: Other rules.
The new structure is enabled by sectioning the accounting file in a manner similar to the rules file. The sections are INPUT, OUTPUT and FORWARD and must appear in that order (although any of them may be omitted). The first non-commentary record in the accounting file must be a section header when sectioning is used.
If sections are not used, the Shorewall rules compiler cannot detect certain violations of netfilter restrictions. These violations can result in run-time errors such as the following:
iptables-restore v1.4.13: Can't use -o with INPUT
Beginning with Shorewall 4.4.20, the ACCOUNTING_TABLE setting was added to shorewall.conf and shorewall6.conf. That setting determines the Netfilter table (filter or mangle) where the accounting rules are added. When ACCOUNTING_TABLE=mangle is specified, the available sections are PREROUTING, INPUT, OUTPUT, FORWARD and POSTROUTING.
Section headers have the form:
?SECTION
section-name
When sections are enabled:
A jump to a user-defined accounting chain must appear before entries that add rules to that chain. This eliminates loops and unreferenced chains.
An output interface may not be specified in the PREROUTING and INPUT sections.
In the OUTPUT and POSTROUTING sections:
An input interface may not be specified
Jumps to a chain defined in the INPUT or PREROUTING sections that specifies an input interface are prohibited
MAC addresses may not be used
Jump to a chain defined in the INPUT or PREROUTING section that specifies a MAC address are prohibited.
The default value of the CHAIN column is:
accountin in the INPUT section
accountout in the OUTPUT section
accountfwd in the FORWARD section
accountpre in the PREROUTING section
accountpost in the POSTROUTING section
Traffic addressed to the firewall goes through the rules defined in the INPUT section.
Traffic originating on the firewall goes through the rules defined in the OUTPUT section.
Traffic being forwarded through the firewall goes through the rules from the FORWARD sections.
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):
table,network)|[?]COMMENT
comment}What to do when a matching packet is found.
Simply count the match and continue with the next rule
Count the match and don't attempt to match any other accounting rules in the chain specified in the CHAIN column.
Where chain is the name of a chain;
shorewall will create the chain automatically if it doesn't
already exist. If a second chain is mentioned in the CHAIN
column, then a jump from this second chain to
chain is created. If no chain is
named in the CHAIN column, then a jump from the default chain
to chain is created. If :COUNT is included, a counting rule
matching this entry will be added to
chain. The chain may
not exceed 29 characters in length and may be composed of
letters, digits, dash ('-') and underscore ('_').
Like the previous option without the :COUNT part.
table,network)This action implements per-IP accounting and was added in Shorewall 4.4.17. Requires the ACCOUNT Target capability in your iptables and kernel (see the output of shorewall show capabilities).
tableis the name of an accounting table (you choose the name). All rules specifying the same name will have their per-IP counters accumulated in the same table.
networkis an IPv4 network in CIDR notation (e.g., 192.168.1.0/24). The network can be as large as a /8 (class A).
One nice feature of per-IP accounting is that the counters survive shorewall restart. This has a downside, however. If you change the network associated with an accounting table, then you must shorewall stop; shorewall start to have a successful restart (counters will be cleared).
The counters in a table are
printed using the iptaccount utility. For a
command synopsis, type:
iptaccount --help
As of February 2011, the ACCOUNT Target capability and the iptaccount utility are only available when xtables-addons is installed. See https://shorewall.org/Accounting.html#perIP for additional information.
Added in Shorewall 4.5.16. Allows free form iptables matches to be specified following a ';'. In the generated iptables rule(s), the free form matches will follow any matches that are generated by the column contents.
object[!]}[,...])Added in Shorewall 4.5.7. Provides a form of accounting
that survives shorewall stop/shorewall
start and shorewall restart. Requires the
NFaccnt Match capability in your kernel and iptables.
object names an nfacct object (see
man nfaccnt(8)). Multiple rules can specify the same
object; all packets that match any
of the rules increment the packet and bytes count of the
object.
Prior to Shorewall 4.5.16, only one
object could be specified.
Beginning with Shorewall 4.5.16, an arbitrary number of
objects may be given.
With Shorewall 4.5.16 or later, an nfacct
object in the list may optionally
be followed by ! to indicate
that the nfacct object will be
incremented unconditionally for each packet. When ! is omitted, the
object will be incremented only if
all of the matches in the rule succeed.
Causes each matching packet to be sent via the currently loaded logging back-end (usually nfnetlink_log) where it is available to accounting daemons through a netlink socket.
The remainder of the line is treated as a comment which is attached to subsequent rules until another COMMENT line is found or until the end of the file is reached. To stop adding comments to rules, use a line with only the word ?COMMENT.
The name of a chain. If specified as - the accounting chain is assumed when the file is un-sectioned. When the file is sectioned, the default is one of accountin, accountout, etc. depending on the section. This is the chain where the accounting rule is added. The chain will be created if it doesn't already exist. The chain may not exceed 29 characters in length.
Packet Source.
The name of an interface, an
address (host or net) or an
interface name followed by ":" and a host
or net address. An ipset name is also
accepted as an address.
This column was formerly named DESTINATION.
Packet Destination.
Format same as SOURCE column.
This column was formerly named PROTOCOL
A protocol-name (from protocols(5)), a protocol-number, ipp2p, ipp2p:udp or ipp2p:all
Beginning with Shorewall 4.5.12, this column can accept a comma-separated list of protocols.
Destination Port number. Service name from services(5) or port number. May only be specified if the protocol is TCP (6), UDP (17), DCCP (33), SCTP (132) or UDPLITE (136).
You may place a comma-separated list of port names or numbers in this column if your kernel and iptables include multi-port match support.
If the PROTOCOL is ipp2p then this column must contain an ipp2p-option ("iptables -m ipp2p --help") without the leading "--". If no option is given in this column, ipp2p is assumed.
This column was formerly named DEST PORT(S).
Service name from services(5) or port number. May only be specified if the protocol is TCP (6), UDP (17), DCCP (33), SCTP (132) or UDPLITE (136).
You may place a comma-separated list of port numbers in this column if your kernel and iptables include multi-port match support.
Beginning with Shorewall 4.5.15, you may place '=' in this column, provided that the DEST PORT(S) column is non-empty. This causes the rule to match when either the source port or the destination port in a packet matches one of the ports specified in DPORT. Use of '=' requires multi-port match in your iptables and kernel.
This column was formerly labelled SOURCE PORT(S).
This column was formerly named USER/GROUP and may only be non-empty if the CHAIN is OUTPUT.
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:
program must be run by joe
program must be run by a member of the 'kids' group
program must not be run by a member of the 'kids' group
#program named upnpd
The ability to specify a program name was removed from Netfilter in kernel version 2.6.14.
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 of the packet or connection mark.
A mask to be applied to the mark before testing.
Designates a connection mark. If omitted, the packet mark's value is tested.
The option-list consists of a comma-separated list of options from the following list. Only packets that will be encrypted or have been decrypted via an SA that matches these options will have their source address changed.
where number is specified using setkey(8) using the 'unique:number option for the SPD level.
where number is the SPI of the SA used to encrypt/decrypt packets.
IPSEC Encapsulation Protocol
sets the MSS field in TCP packets
IPSEC mode
only available with mode=tunnel
only available with mode=tunnel
Means that packets must match all rules.
Separates rules; can only be used with strict
When used by itself, causes all traffic that will be encrypted/encapsulated or has been decrypted/un-encapsulated to match the rule.
When used by itself, causes all traffic that will not be encrypted/encapsulated or has been decrypted/un-encapsulated to match the rule.
May only be used in the FORWARD section and must be the first or the only item the list. Indicates that matching packets have been decrypted in input.
May only be used in the FORWARD section and must be the first or the only item in the list. Indicates that matching packets will be encrypted on output.
If this column is non-empty and sections are not used, then:
A chain NAME appearing in the ACTION column must be a chain branched either directly or indirectly from the accipsecin or accipsecout chain.
The CHAIN column must contain either accipsecin or accipsecout or a chain branched either directly or indirectly from those chains.
These rules will NOT appear in the accounting chain.
In all of the above columns except ACTION and CHAIN, the values -, any and all may be used as wildcard'gs. Omitted trailing columns are also treated as wildcard'g.