# # Shorewall version 3.0 - Sample Rules File for one-interface configuration. # # /etc/shorewall/rules # # Rules in this file govern connection establishment. Requests and # responses are automatically allowed using connection tracking. For any # particular (source,dest) pair of zones, the rules are evaluated in the # order in which they appear in this file and the first match is the one # that determines the disposition of the request. # # In most places where an IP address or subnet is allowed, you # can preceed the address/subnet with "!" (e.g., !192.168.1.0/24) to # indicate that the rule matches all addresses except the address/subnet # given. Notice that no white space is permitted between "!" and the # address/subnet. #------------------------------------------------------------------------------ # WARNING: If you masquerade or use SNAT from a local system to the internet, # you cannot use an ACCEPT rule to allow traffic from the internet to # that system. You *must* use a DNAT rule instead. #------------------------------------------------------------------------------ # # The rules file is divided into sections. Each section is introduced by # a "Section Header" which is a line beginning with SECTION followed by the # section name. # # Sections are as follows and must appear in the order listed: # # ESTABLISHED Packets in the ESTABLISHED state are processed # by rules in this section. # # The only ACTIONs allowed in this section are # ACCEPT, DROP, REJECT, LOG and QUEUE # # There is an implicit ACCEPT rule inserted # at the end of this section. # # RELATED Packets in the RELATED state are processed by # rules in this section. # # The only ACTIONs allowed in this section are # ACCEPT, DROP, REJECT, LOG and QUEUE # # There is an implicit ACCEPT rule inserted # at the end of this section. # # NEW Packets in the NEW and INVALID states are # processed by rules in this section. # # WARNING: If you specify FASTACCEPT=Yes in shorewall.conf then the # ESTABLISHED and RELATED sections must be empty. # # Note: If you are not familiar with Netfilter to the point where you are # comfortable with the differences between the various connection # tracking states, then I suggest that you omit the ESTABLISHED and # RELATED sections and place all of your rules in the NEW section. # # You may omit any section that you don't need. If no Section Headers appear # in the file then all rules are assumed to be in the NEW section. # # Columns are: # # ACTION ACCEPT, DROP, REJECT, DNAT, DNAT-, REDIRECT, CONTINUE, # LOG, QUEUE or an . # # ACCEPT -- allow the connection request # ACCEPT+ -- like ACCEPT but also excludes the # connection from any subsequent # DNAT[-] or REDIRECT[-] rules # NONAT -- Excludes the connection from any # subsequent DNAT[-] or REDIRECT[-] # rules but doesn't generate a rule # to accept the traffic. # DROP -- ignore the request # REJECT -- disallow the request and return an # icmp-unreachable or an RST packet. # DNAT -- Forward the request to another # system (and optionally another # port). # DNAT- -- Advanced users only. # Like DNAT but only generates the # DNAT iptables rule and not # the companion ACCEPT rule. # SAME -- Similar to DNAT except that the # port may not be remapped and when # multiple server addresses are # listed, all requests from a given # remote system go to the same # server. # SAME- -- Advanced users only. # Like SAME but only generates the # NAT iptables rule and not # the companion ACCEPT rule. # REDIRECT -- Redirect the request to a local # port on the firewall. # REDIRECT- # -- Advanced users only. # Like REDIRET but only generates the # REDIRECT iptables rule and not # the companion ACCEPT rule. # # CONTINUE -- (For experts only). Do not process # any of the following rules for this # (source zone,destination zone). If # The source and/or destination IP # address falls into a zone defined # later in /etc/shorewall/zones, this # connection request will be passed # to the rules defined for that # (those) zone(s). # LOG -- Simply log the packet and continue. # QUEUE -- Queue the packet to a user-space # application such as ftwall # (http://p2pwall.sf.net). # -- The name of an action defined in # /etc/shorewall/actions or in # /usr/share/shorewall/actions.std. # -- The name of a macro defined in a # file named macro.. If # the macro accepts an action # parameter (Look at the macro # source to see if it has PARAM in # the TARGET column) then the macro # name is followed by "/" and the # action (ACCEPT, DROP, REJECT, ...) # to be substituted for the # parameter. Example: FTP/ACCEPT. # # The ACTION may optionally be followed # by ":" and a syslog log level (e.g, REJECT:info or # DNAT:debug). This causes the packet to be # logged at the specified level. # # If the ACTION names an action defined in # /etc/shorewall/actions or in # /usr/share/shorewall/actions.std then: # # - If the log level is followed by "!' then all rules # in the action are logged at the log level. # # - If the log level is not followed by "!" then only # those rules in the action that do not specify # logging are logged at the specified level. # # - The special log level 'none!' suppresses logging # by the action. # # You may also specify ULOG (must be in upper case) as a # log level.This will log to the ULOG target for routing # to a separate log through use of ulogd # (http://www.gnumonks.org/projects/ulogd). # # Actions specifying logging may be followed by a # log tag (a string of alphanumeric characters) # are appended to the string generated by the # LOGPREFIX (in /etc/shorewall/shorewall.conf). # # Example: ACCEPT:info:ftp would include 'ftp ' # at the end of the log prefix generated by the # LOGPREFIX setting. # # SOURCE Source hosts to which the rule applies. May be a zone # defined in /etc/shorewall/zones, $FW to indicate the # firewall itself, "all", "all+" or "none" If the ACTION # is DNAT or REDIRECT, sub-zones of the specified zone # may be excluded from the rule by following the zone # name with "!' and a comma-separated list of sub-zone # names. # # When "none" is used either in the SOURCE or DEST # column, the rule is ignored. # # When "all" is used either in the SOURCE or DEST column # intra-zone traffic is not affected. When "all+" is # used, intra-zone traffic is affected. # # Except when "all[+]" is specified, clients may be # further restricted to a list of subnets and/or hosts by # appending ":" and a comma-separated list of subnets # and/or hosts. Hosts may be specified by IP or MAC # address; mac addresses must begin with "~" and must use # "-" as a separator. # # Hosts may be specified as an IP address range using the # syntax -. This requires that # your kernel and iptables contain iprange match support. # If you kernel and iptables have ipset match support # then you may give the name of an ipset prefaced by "+". # The ipset name may be optionally followed by a number # from 1 to 6 enclosed in square brackets ([]) to # indicate the number of levels of source bindings to be # matched. # # dmz:192.168.2.2 Host 192.168.2.2 in the DMZ # # net:155.186.235.0/24 Subnet 155.186.235.0/24 on the # Internet # # loc:192.168.1.1,192.168.1.2 # Hosts 192.168.1.1 and # 192.168.1.2 in the local zone. # loc:~00-A0-C9-15-39-78 Host in the local zone with # MAC address 00:A0:C9:15:39:78. # # net:192.0.2.11-192.0.2.17 # Hosts 192.0.2.11-192.0.2.17 in # the net zone. # # Alternatively, clients may be specified by interface # by appending ":" to the zone name followed by the # interface name. For example, loc:eth1 specifies a # client that communicates with the firewall system # through eth1. This may be optionally followed by # another colon (":") and an IP/MAC/subnet address # as described above (e.g., loc:eth1:192.168.1.5). # # DEST Location of Server. May be a zone defined in # /etc/shorewall/zones, $FW to indicate the firewall # itself, "all". "all+" or "none". # # When "none" is used either in the SOURCE or DEST # column, the rule is ignored. # # When "all" is used either in the SOURCE or DEST column # intra-zone traffic is not affected. When "all+" is # used, intra-zone traffic is affected. # # Except when "all[+]" is specified, the server may be # further restricted to a particular subnet, host or # interface by appending ":" and the subnet, host or # interface. See above. # # Restrictions: # # 1. MAC addresses are not allowed. # 2. In DNAT rules, only IP addresses are # allowed; no FQDNs or subnet addresses # are permitted. # 3. You may not specify both an interface and # an address. # # Like in the SOURCE column, you may specify a range of # up to 256 IP addresses using the syntax # -. When the ACTION is DNAT or DNAT-, # the connections will be assigned to addresses in the # range in a round-robin fashion. # # If you kernel and iptables have ipset match support # then you may give the name of an ipset prefaced by "+". # The ipset name may be optionally followed by a number # from 1 to 6 enclosed in square brackets ([]) to # indicate the number of levels of destination bindings # to be matched. Only one of the SOURCE and DEST columns # may specify an ipset name. # # The port that the server is listening on may be # included and separated from the server's IP address by # ":". If omitted, the firewall will not modifiy the # destination port. A destination port may only be # included if the ACTION is DNAT or REDIRECT. # # Example: loc:192.168.1.3:3128 specifies a local # server at IP address 192.168.1.3 and listening on port # 3128. The port number MUST be specified as an integer # and not as a name from /etc/services. # # if the ACTION is REDIRECT, this column needs only to # contain the port number on the firewall that the # request should be redirected to. # # PROTO Protocol - Must be "tcp", "udp", "icmp", "ipp2p", # "ipp2p:udp", "ipp2p:all" a number, or "all". # "ipp2p*" requires ipp2p match support in your kernel # and iptables. # # DEST PORT(S) Destination Ports. A comma-separated list of Port # names (from /etc/services), port numbers or port # ranges; if the protocol is "icmp", this column is # interpreted as the destination icmp-type(s). # # If the protocol is ipp2p, this column is interpreted # as an ipp2p option without the leading "--" (example # "bit" for bit-torrent). If no port is given, "ipp2p" is # assumed. # # A port range is expressed as :. # # This column is ignored if PROTOCOL = all but must be # entered if any of the following ields are supplied. # In that case, it is suggested that this field contain # "-" # # If your kernel contains multi-port match support, then # only a single Netfilter rule will be generated if in # this list and the CLIENT PORT(S) list below: # 1. There are 15 or less ports listed. # 2. No port ranges are included. # Otherwise, a separate rule will be generated for each # port. # # CLIENT PORT(S) (Optional) Port(s) used by the client. If omitted, # any source port is acceptable. Specified as a comma- # separated list of port names, port numbers or port # ranges. # # If you don't want to restrict client ports but need to # specify an ORIGINAL DEST in the next column, then # place "-" in this column. # # If your kernel contains multi-port match support, then # only a single Netfilter rule will be generated if in # this list and the DEST PORT(S) list above: # 1. There are 15 or less ports listed. # 2. No port ranges are included. # Otherwise, a separate rule will be generated for each # port. # # ORIGINAL DEST (0ptional) -- If ACTION is DNAT[-] or REDIRECT[-] # then if included and different from the IP # address given in the SERVER column, this is an address # on some interface on the firewall and connections to # that address will be forwarded to the IP and port # specified in the DEST column. # # A comma-separated list of addresses may also be used. # This is usually most useful with the REDIRECT target # where you want to redirect traffic destined for # particular set of hosts. # # Finally, if the list of addresses begins with "!" then # the rule will be followed only if the original # destination address in the connection request does not # match any of the addresses listed. # # For other actions, this column may be included and may # contain one or more addresses (host or network) # separated by commas. Address ranges are not allowed. # When this column is supplied, rules are generated # that require that the original destination address # matches one of the listed addresses. This feature is # most useful when you want to generate a filter rule # that corresponds to a DNAT- or REDIRECT- rule. In this # usage, the list of addresses should not begin with "!". # # See http://shorewall.net/PortKnocking.html for an # example of using an entry in this column with a # user-defined action rule. # # RATE LIMIT You may rate-limit the rule by placing a value in # this colume: # # /[:] # # where is the number of connections per # ("sec" or "min") and is the # largest burst permitted. If no is given, # a value of 5 is assumed. There may be no # no whitespace embedded in the specification. # # Example: 10/sec:20 # # USER/GROUP This column may only be non-empty if the SOURCE is # the firewall itself. # # The column may contain: # # [!][][:][+] # # When this column is non-empty, the rule applies only # if the program generating the output is running under # the effective and/or specified (or is # NOT running under that id if "!" is given). # # Examples: # # joe #program must be run by joe # :kids #program must be run by a member of # #the 'kids' group # !:kids #program must not be run by a member # #of the 'kids' group # +upnpd #program named upnpd (This feature was # #removed from Netfilter in kernel # #version 2.6.14). # # Example: Accept SMTP requests from the DMZ to the internet # # #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # # PORT PORT(S) DEST # ACCEPT dmz net tcp smtp # # Example: Forward all ssh and http connection requests from the # internet to local system 192.168.1.3 # # #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # # PORT PORT(S) DEST # DNAT net loc:192.168.1.3 tcp ssh,http # # Example: Forward all http connection requests from the internet # to local system 192.168.1.3 with a limit of 3 per second and # a maximum burst of 10 # # #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE # # PORT PORT(S) DEST LIMIT # DNAT net loc:192.168.1.3 tcp http - - 3/sec:10 # # Example: Redirect all locally-originating www connection requests to # port 3128 on the firewall (Squid running on the firewall # system) except when the destination address is 192.168.2.2 # # #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # # PORT PORT(S) DEST # REDIRECT loc 3128 tcp www - !192.168.2.2 # # Example: All http requests from the internet to address # 130.252.100.69 are to be forwarded to 192.168.1.3 # # #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # # PORT PORT(S) DEST # DNAT net loc:192.168.1.3 tcp 80 - 130.252.100.69 # # Example: You want to accept SSH connections to your firewall only # from internet IP addresses 130.252.100.69 and 130.252.100.70 # # #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL # # PORT PORT(S) DEST # ACCEPT net:130.252.100.69,130.252.100.70 $FW \ # tcp 22 ############################################################################################################# #ACTION SOURCE DEST PROTO DEST SOURCE ORIGINAL RATE USER/ # PORT PORT(S) DEST LIMIT GROUP # Reject Ping from the "bad" net zone.. and prevent your log from being flooded.. Ping/REJECT net $FW # Permit all ICMP traffic FROM the firewall TO the net zone ACCEPT $FW net icmp #LAST LINE -- ADD YOUR ENTRIES BEFORE THIS ONE -- DO NOT REMOVE