BNF revision 67615
1filter-rule = [ insert ] action in-out [ options ] [ tos ] [ ttl ] 2 [ proto ] [ ip ] [ group ]. 3 4insert = "@" decnumber . 5action = block | "pass" | log | "count" | skip | auth | call . 6in-out = "in" | "out" . 7options = [ log ] [ "quick" ] [ "on" interface-name [ dup ] [ froute ] ] . 8tos = "tos" decnumber | "tos" hexnumber . 9ttl = "ttl" decnumber . 10proto = "proto" protocol . 11ip = srcdst [ flags ] [ with withopt ] [ icmp ] [ keep ] . 12group = [ "head" decnumber ] [ "group" decnumber ] . 13 14block = "block" [ reutrn-icmp[return-code] | "return-rst" ] . 15auth = "auth" | "preauth" . 16log = "log" [ "body" ] [ "first" ] [ "or-block" ] [ "level" loglevel ] . 17call = "call" [ "now" ] function-name . 18skip = "skip" decnumber . 19dup = "dup-to" interface-name[":"ipaddr] . 20froute = "fastroute" | "to" interface-name . 21protocol = "tcp/udp" | "udp" | "tcp" | "icmp" | decnumber . 22srcdst = "all" | fromto . 23fromto = "from" object "to" object . 24 25reutrn-icmp = "return-icmp" | "return-icmp-as-dest" . 26loglevel = facility"."priority | priority . 27object = addr [ port-comp | port-range ] . 28addr = "any" | nummask | host-name [ "mask" ipaddr | "mask" hexnumber ] . 29port-comp = "port" compare port-num . 30port-range = "port" port-num range port-num . 31flags = "flags" flag { flag } [ "/" flag { flag } ] . 32with = "with" | "and" . 33icmp = "icmp-type" icmp-type [ "code" decnumber ] . 34return-code = "("icmp-code")" . 35keep = "keep" "state" | "keep" "frags" . 36 37nummask = host-name [ "/" decnumber ] . 38host-name = ipaddr | hostname | "any" . 39ipaddr = host-num "." host-num "." host-num "." host-num . 40host-num = digit [ digit [ digit ] ] . 41port-num = service-name | decnumber . 42 43withopt = [ "not" | "no" ] opttype [ withopt ] . 44opttype = "ipopts" | "short" | "frag" | "opt" ipopts . 45optname = ipopts [ "," optname ] . 46ipopts = optlist | "sec-class" [ secname ] . 47secname = seclvl [ "," secname ] . 48seclvl = "unclass" | "confid" | "reserv-1" | "reserv-2" | "reserv-3" | 49 "reserv-4" | "secret" | "topsecret" . 50icmp-type = "unreach" | "echo" | "echorep" | "squench" | "redir" | 51 "timex" | "paramprob" | "timest" | "timestrep" | "inforeq" | 52 "inforep" | "maskreq" | "maskrep" | "routerad" | 53 "routersol" | decnumber . 54icmp-code = decumber | "net-unr" | "host-unr" | "proto-unr" | "port-unr" | 55 "needfrag" | "srcfail" | "net-unk" | "host-unk" | "isolate" | 56 "net-prohib" | "host-prohib" | "net-tos" | "host-tos" | 57 "filter-prohib" | "host-preced" | "cutoff-preced" . 58optlist = "nop" | "rr" | "zsu" | "mtup" | "mtur" | "encode" | "ts" | "tr" | 59 "sec" | "lsrr" | "e-sec" | "cipso" | "satid" | "ssrr" | "addext" | 60 "visa" | "imitd" | "eip" | "finn" . 61facility = "kern" | "user" | "mail" | "daemon" | "auth" | "syslog" | 62 "lpr" | "news" | "uucp" | "cron" | "ftp" | "authpriv" | 63 "audit" | "logalert" | "local0" | "local1" | "local2" | 64 "local3" | "local4" | "local5" | "local6" | "local7" . 65priority = "emerg" | "alert" | "crit" | "err" | "warn" | "notice" | 66 "info" | "debug" . 67 68hexnumber = "0" "x" hexstring . 69hexstring = hexdigit [ hexstring ] . 70decnumber = digit [ decnumber ] . 71 72compare = "=" | "!=" | "<" | ">" | "<=" | ">=" | "eq" | "ne" | "lt" | "gt" | 73 "le" | "ge" . 74range = "<>" | "><" . 75hexdigit = digit | "a" | "b" | "c" | "d" | "e" | "f" . 76digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" . 77flag = "F" | "S" | "R" | "P" | "A" | "U" . 78