Document the latest firewall knobs.

This commit is contained in:
Ruslan Ermilov 2000-10-06 11:17:06 +00:00
parent e8af5965e2
commit 79a74459fa
2 changed files with 91 additions and 32 deletions

View File

@ -269,20 +269,32 @@ Each packet can be filtered based on the following information that is
associated with it:
.Pp
.Bl -tag -width "Source and destination IP address" -offset indent -compact
.It Transmit and receive interface
(by name or address)
.It Direction
(incoming or outgoing)
.It Source and destination IP address
(possibly masked)
.It Protocol
(TCP, UDP, ICMP, etc.)
.It Source and destination IP address
(possibly masked)
.It Source and destination port
(lists, ranges or masks)
.It TCP flags
.It Direction
(incoming or outgoing)
.It Transmit and receive interface
(by name or address)
.It IP version
.It IP type of service
.It IP datagram length
.It IP identification
.It IP fragment flag
(non-zero IP offset)
.It IP time to live
.It IP options
.It TCP sequence number
.It TCP acknowledgment number
.It TCP flags
(SYN, FIN, ACK, RST, etc.)
.It TCP window
.It TCP options
.It ICMP types
(for ICMP packets)
.It User/group ID of the socket associated with the packet
.El
.Pp
@ -473,7 +485,7 @@ keywords mean any protocol will match.
The
.Aq Ar address Ns / Ns Ar mask
may be specified as:
.Bl -tag -width indent
.Bl -tag -width "ipno/bits"
.It Ar ipno
An IP number of the form 1.2.3.4.
Only this exact IP number will match the rule.
@ -627,6 +639,35 @@ when using
.Em pipes
because the same packet would be accounted for twice in terms
of bandwidth, queue occupation, and also counters.
.It Cm ipversion Ar ver
Match if the IP header version is
.Ar ver .
.It Cm iptos Ar spec
Match if the IP header contains the comma separated list of
service types specified in
.Ar spec .
The supported IP types of service are:
.Pp
.Cm lowdelay
.Pq Dv IPTOS_LOWDELAY ,
.Cm throughput
.Pq Dv IPTOS_THROUGHPUT ,
.Cm reliability
.Pq Dv IPTOS_RELIABILITY ,
.Cm mincost
.Pq Dv IPTOS_MINCOST ,
.Cm congestion
.Pq Dv IPTOS_CE .
The absence of a particular type may be denoted
with a
.Ql ! .
.It Cm iplen Ar len
Match if the total length of a packet, including header and data, is
.Ar len
bytes.
.It Cm ipid Ar id
Match if the identification of IP datagram is
.Ar id .
.It Cm frag
Match if the packet is a fragment and this is not the first
fragment of the datagram.
@ -634,6 +675,9 @@ fragment of the datagram.
may not be used in conjunction with either
.Cm tcpflags
or TCP/UDP port specifications.
.It Cm ipttl Ar ttl
Match if the time to live of IP datagram is
.Ar ttl .
.It Cm ipoptions Ar spec
Match if the IP header contains the comma separated list of
options specified in
@ -651,31 +695,14 @@ The supported IP options are:
The absence of a particular option may be denoted
with a
.Ql ! .
.It Cm tcpoptions Ar spec
Match if the TCP header contains the comma separated list of
options specified in
.Ar spec .
The supported TCP options are:
.Pp
.Cm mss
(maximum segment size),
.Cm window
(tcp window advertisement),
.Cm sack
(selective ack),
.Cm ts
(rfc1323 timestamp) and
.Cm cc
(rfc1644 t/tcp connection count).
The absence of a particular option may be denoted
with a
.Ql ! .
.It Cm established
.It Cm tcpseq Ar seq
TCP packets only.
Match packets that have the RST or ACK bits set.
.It Cm setup
Match if the TCP header sequence number field is set to
.Ar seq .
.It Cm tcpack Ar ack
TCP packets only.
Match packets that have the SYN bit set but no ACK bit.
Match if the TCP header acknowledgment number field is set to
.Ar ack .
.It Cm tcpflags Ar spec
TCP packets only.
Match if the TCP header contains the comma separated list of
@ -700,6 +727,38 @@ a non-zero offset.
See the
.Cm frag
option for details on matching fragmented packets.
.It Cm established
TCP packets only.
Match packets that have the RST or ACK bits set.
.It Cm setup
TCP packets only.
Match packets that have the SYN bit set but no ACK bit.
This is the short form of
.Dq Li tcpflags\ syn,!ack .
.It Cm tcpwin Ar win
TCP packets only.
Match if the TCP header window field is set to
.Ar win .
.It Cm tcpoptions Ar spec
TCP packets only.
Match if the TCP header contains the comma separated list of
options specified in
.Ar spec .
The supported TCP options are:
.Pp
.Cm mss
(maximum segment size),
.Cm window
(tcp window advertisement),
.Cm sack
(selective ack),
.Cm ts
(rfc1323 timestamp) and
.Cm cc
(rfc1644 t/tcp connection count).
The absence of a particular option may be denoted
with a
.Ql ! .
.It Cm icmptypes Ar types
ICMP packets only.
Match if the ICMP type is in the list

View File

@ -873,7 +873,7 @@ show_usage(const char *fmt, ...)
" ipoptions [!]{ssrr|lsrr|rr|ts},...\n"
" iplen {length}\n"
" ipid {identification number}\n"
" iptos [!]{lowdelay|throughput|reliability|mincost|congestion}\n"
" iptos [!]{lowdelay|throughput|reliability|mincost|congestion},...\n"
" ipttl {time to live}\n"
" ipversion {version number}\n"
" tcpoptions [!]{mss|window|sack|ts|cc},...\n"