net.java.slee.resource.diameter.base.events.avp
Interface IPFilterRuleAvp
- All Known Implementing Classes:
- IPFilterRuleAvpImpl
public interface IPFilterRuleAvp
Java class to represent the Diameter IPFilterRule AVP type.
The IPFilterRule format is derived from the OctetString AVP Base Format. It uses the ASCII charset.
Packets may be filtered based on the following information that is associated with it.
Direction (in or out)
Source and destination IP address (possibly masked)
Protocol
Source and destination port (lists or ranges)
TCP flags
IP fragment flag
IP options
ICMP types
Rules for the appropriate direction are evaluated in order, with
the first matched rule terminating the evaluation. Each packet is
evaluated once. If no rule matches, the packet is dropped if the
last rule evaluated was a permit, and passed if the last rule was
a deny.
IPFilterRule filters MUST follow the format:
action dir proto from src to dst [options]
action permit - Allow packets that match the rule.
deny - Drop packets that match the rule.
dir "in" is from the terminal, "out" is to the
terminal.
proto An IP protocol specified by number. The "ip"
keyword means any protocol will match.
src and dst <address/mask> [ports]
The <address/mask> may be specified as:
ipno An IPv4 or IPv6 number in dotted-
quad or canonical IPv6 form. Only
this exact IP number will match the
rule.
ipno/bits An IP number as above with a mask
width of the form 1.2.3.4/24. In
this case, all IP numbers from
1.2.3.0 to 1.2.3.255 will match.
The bit width MUST be valid for the
IP version and the IP number MUST
NOT have bits set beyond the mask.
For a match to occur, the same IP
version must be present in the
packet that was used in describing
the IP address. To test for a
particular IP version, the bits part
can be set to zero. The keyword
"any" is 0.0.0.0/0 or the IPv6
equivalent. The keyword "assigned"
is the address or set of addresses
assigned to the terminal. For IPv4,
a typical first rule is often "deny
in ip! assigned"
The sense of the match can be inverted by
preceding an address with the not modifier (!),
causing all other addresses to be matched
instead. This does not affect the selection of
port numbers.
With the TCP, UDP and SCTP protocols, optional
ports may be specified as:
{port/port-port}[,ports[,...]]
The '-' notation specifies a range of ports
(including boundaries).
Fragmented packets that have a non-zero offset
(i.e., not the first fragment) will never match
a rule that has one or more port
specifications. See the frag option for
details on matching fragmented packets.
options:
frag Match if the packet is a fragment and this is not
the first fragment of the datagram. frag may not
be used in conjunction with either tcpflags or
TCP/UDP port specifications.
ipoptions spec
Match if the IP header contains the comma
separated list of options specified in spec. The
supported IP options are:
ssrr (strict source route), lsrr (loose source
route), rr (record packet route) and ts
(timestamp). The absence of a particular option
may be denoted with a '!'.
tcpoptions spec
Match if the TCP header contains the comma
separated list of options specified in spec. The
supported TCP options are:
mss (maximum segment size), window (tcp window
advertisement), sack (selective ack), ts (rfc1323
timestamp) and cc (rfc1644 t/tcp connection
count). The absence of a particular option may
be denoted with a '!'.
established
TCP packets only. Match packets that have the RST
or ACK bits set.
setup TCP packets only. Match packets that have the SYN
bit set but no ACK bit.
tcpflags spec
TCP packets only. Match if the TCP header
contains the comma separated list of flags
specified in spec. The supported TCP flags are:
fin, syn, rst, psh, ack and urg. The absence of a
particular flag may be denoted with a '!'. A rule
that contains a tcpflags specification can never
match a fragmented packet that has a non-zero
offset. See the frag option for details on
matching fragmented packets.
icmptypes types
ICMP packets only. Match if the ICMP type is in
the list types. The list may be specified as any
combination of ranges or individual types
separated by commas. Both the numeric values and
the symbolic values listed below can be used. The
supported ICMP types are:
echo reply (0), destination unreachable (3),
source quench (4), redirect (5), echo request
(8), router advertisement (9), router
solicitation (10), time-to-live exceeded (11), IP
header bad (12), timestamp request (13),
timestamp reply (14), information request (15),
information reply (16), address mask request (17)
and address mask reply (18).
There is one kind of packet that the access device MUST always
discard, that is an IP fragment with a fragment offset of one. This
is a valid packet, but it only has one use, to try to circumvent
firewalls.
An access device that is unable to interpret or apply a deny rule
MUST terminate the session. An access device that is unable to
interpret or apply a permit rule MAY apply a more restrictive
rule. An access device MAY apply deny rules of its own before the
supplied rules, for example to protect the access device owner's
infrastructure.
The rule syntax is a modified subset of ipfw(8) from FreeBSD.
- Author:
- Open Cloud
getAction
int getAction()
getDirection
int getDirection()
isAnyProtocol
boolean isAnyProtocol()
getProtocol
int getProtocol()
getSourceIp
java.lang.String getSourceIp()
getSourceBits
int getSourceBits()
isSourceAssignedIps
boolean isSourceAssignedIps()
getSourcePorts
int[][] getSourcePorts()
getDestIp
java.lang.String getDestIp()
getDestBits
int getDestBits()
isDestAssignedIps
boolean isDestAssignedIps()
getDestPorts
int[][] getDestPorts()
isFragment
boolean isFragment()
getIpOptions
java.lang.String[] getIpOptions()
getTcpOptions
java.lang.String[] getTcpOptions()
isEstablised
boolean isEstablised()
isSetup
boolean isSetup()
getTcpFlags
java.lang.String[] getTcpFlags()
getIcmpTypes
java.lang.String[] getIcmpTypes()
getNumericIcmpTypes
int[] getNumericIcmpTypes()
Copyright © 2008. All Rights Reserved.