Zhone 2004 ユーザーガイド

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C-6
2 0 0 0 - A 2 - G B 2 2 - 0 0
Other ifnames include ppp0fr0pppoa0hdlc0. Please note that when 
creating and deleting PVCs, ifnames can change. Please review the IP 
Filtering rule set after modifying WAN connections to ensure that the 
rule set is still valid.
JetFusion IP Packet Filtering Syntax and Grammar
Each packet is compared to all the rules in the list for the interface and 
direction, with the last matching rule being applied (exception: see “quick” 
command below). Therefore, the most restrictive rules (block) should be 
placed first in the list, with pass rules following. This will allow only certain 
packet types to traverse the IAD.
NOTICE: 
When modifying or deleting PVCs, the interface names can change. 
Verify the interface names match the desired interfaces after modifying 
or deleting PVCs.
The rules are stored on the IAD in the file, filter.st, and can be viewed 
through the user interface. You may edit the filter.st file external to the IAD 
and then download it to the IAD.
Grammar
The format used for construction of filtering rules can be described using the 
following grammar in BNF:
filter-rule = action in-out [ options ] [ match ] [ keep ]
action 
= “block” | "pass" | “count”
in-out   
= "in" | "out" 
options  
= [ "quick" ] [ "on" interface-name ] 
match    
= [ tos ] [ ttl ] [ proto ] [ ip ] 
keep     
= "keep state"
tos       
= "tos" decnumber | "tos" hexnumber 
ttl       
= "ttl" decnumber 
proto     
= "proto" protocol 
ip       
= srcdst [ flags ] [ with withopt ] [ icmp ] [ keep ] 
protocol 
= "tcp/udp" | "udp" | "tcp" | "icmp" | decnumber 
srcdst    
= "all" | fromto 
fromto     = "from" object "to" object 
object   
= [“!”] addr [ port-comp | port-range ] 
addr 
= "any" | nummask | host-name [ "mask" ipaddr | "mask" hexnumber ] 
port-comp = "port" compare port-num 
port-range = "port" port-num range port-num 
flags     
= "flags" flag { flag } [ "/" flag { flag } ] 
with 
= "with" | "and" 
icmp 
= "icmp-type" icmp-type [ "code" decnumber ]