Getting bad interpreter error
Craig White
plug-discuss@lists.plug.phoenix.az.us
11 Dec 2002 08:49:38 -0700
As root - bad interpreter?
chmod 700 rc.firewall-2.4 (to make sure of privileges)
does 'which sh' return /bin/sh ?
and just for fun...
iptables -L (see if the rules aren't in place already)
Craig
On Wed, 2002-12-11 at 00:00, mazdaracer wrote:
> On executing /etc/rc.d/rc.firewall-2.4 I get a bad interpreter message.
>
> I can execute the tripwire install ok, but not this one.
>
> script attached.
>
> pete
> ----
>
> #!/bin/sh
> #
> # rc.firewall-2.4
> FWVER=0.70
> #
> # Initial SIMPLE IP Masquerade test for 2.4.x kernels
> # using IPTABLES.
> #
> # Once IP Masquerading has been tested, with this simple
> # ruleset, it is highly recommended to use a stronger
> # IPTABLES ruleset either given later in this HOWTO or
> # from another reputable resource.
> #
> #
> #
> # Log:
> # 0.70 - Added commented option for IRC nat module
> # - Added additional use of environment variables
> # - Added additional formatting
> # 0.63 - Added support for the IRC IPTABLES module
> # 0.62 - Fixed a typo on the MASQ enable line that used eth0
> # instead of $EXTIF
> # 0.61 - Changed the firewall to use variables for the internal
> # and external interfaces.
> # 0.60 - 0.50 had a mistake where the ruleset had a rule to DROP
> # all forwarded packets but it didn't have a rule to ACCEPT
> # any packets to be forwarded either
> # - Load the ip_nat_ftp and ip_conntrack_ftp modules by default
> # 0.50 - Initial draft
> #
>
> echo -e "\n\nLoading simple rc.firewall version $FWVER..\n"
>
>
> # The location of the iptables and kernel module programs
> #
> # If your Linux distribution came with a copy of iptables,
> # most likely all the programs will be located in /sbin. If
> # you manually compiled iptables, the default location will
> # be in /usr/local/sbin
> #
> # ** Please use the "whereis iptables" command to figure out
> # ** where your copy is and change the path below to reflect
> # ** your setup
> #
> IPTABLES=/sbin/iptables
> #IPTABLES=/usr/local/sbin/iptables
> DEPMOD=/sbin/depmod
> INSMOD=/sbin/insmod
>
>
> #Setting the EXTERNAL and INTERNAL interfaces for the network
> #
> # Each IP Masquerade network needs to have at least one
> # external and one internal network. The external network
> # is where the natting will occur and the internal network
> # should preferably be addressed with a RFC1918 private address
> # scheme.
> #
> # For this example, "eth0" is external and "eth1" is internal"
> #
> # NOTE: If this doesnt EXACTLY fit your configuration, you must
> # change the EXTIF or INTIF variables above. For example:
> #
> # EXTIF="ppp0"
> #
> # if you are a modem user.
> #
> EXTIF="eth0"
> INTIF="eth1"
> echo " External Interface: $EXTIF"
> echo " Internal Interface: $INTIF"
>
>
> #======================================================================
> #== No editing beyond this line is required for initial MASQ testing ==
>
>
> echo -en " loading modules: "
>
> # Need to verify that all modules have all required dependencies
> #
> echo " - Verifying that all kernel modules are ok"
> $DEPMOD -a
>
> # With the new IPTABLES code, the core MASQ functionality is now either
> # modular or compiled into the kernel. This HOWTO shows ALL IPTABLES
> # options as MODULES. If your kernel is compiled correctly, there is
> # NO need to load the kernel modules manually.
> #
> # NOTE: The following items are listed ONLY for informational reasons.
> # There is no reason to manual load these modules unless your
> # kernel is either mis-configured or you intentionally disabled
> # the kernel module autoloader.
> #
>
> # Upon the commands of starting up IP Masq on the server, the
> # following kernel modules will be automatically loaded:
> #
> # NOTE: Only load the IP MASQ modules you need. All current IP MASQ
> # modules are shown below but are commented out from loading.
> # ===============================================================
>
> echo "----------------------------------------------------------------------"
>
> #Load the main body of the IPTABLES module - "iptable"
> # - Loaded automatically when the "iptables" command is invoked
> #
> # - Loaded manually to clean up kernel auto-loading timing issues
> #
> echo -en "ip_tables, "
> $INSMOD ip_tables
>
>
> #Load the IPTABLES filtering module - "iptable_filter"
> # - Loaded automatically when filter policies are activated
>
>
> #Load the stateful connection tracking framework - "ip_conntrack"
> #
> # The conntrack module in itself does nothing without other specific
> # conntrack modules being loaded afterwards such as the "ip_conntrack_ftp"
> # module
> #
> # - This module is loaded automatically when MASQ functionality is
> # enabled
> #
> # - Loaded manually to clean up kernel auto-loading timing issues
> #
> echo -en "ip_conntrack, "
> $INSMOD ip_conntrack
>
>
> #Load the FTP tracking mechanism for full FTP tracking
> #
> # Enabled by default -- insert a "#" on the next line to deactivate
> #
> echo -en "ip_conntrack_ftp, "
> $INSMOD ip_conntrack_ftp
>
>
> #Load the IRC tracking mechanism for full IRC tracking
> #
> # Enabled by default -- insert a "#" on the next line to deactivate
> #
> echo -en "ip_conntrack_irc, "
> $INSMOD ip_conntrack_irc
>
>
> #Load the general IPTABLES NAT code - "iptable_nat"
> # - Loaded automatically when MASQ functionality is turned on
> #
> # - Loaded manually to clean up kernel auto-loading timing issues
> #
> echo -en "iptable_nat, "
> $INSMOD iptable_nat
>
>
> #Loads the FTP NAT functionality into the core IPTABLES code
> # Required to support non-PASV FTP.
> #
> # Enabled by default -- insert a "#" on the next line to deactivate
> #
> echo -en "ip_nat_ftp, "
> $INSMOD ip_nat_ftp
>
>
> #Loads the IRC NAT functionality into the core IPTABLES code
> # Require to support NAT of IRC DCC requests
> #
> # Disabled by default -- remove the "#" on the next line to activate
> #
> #echo -e "ip_nat_irc"
> #$INSMOD ip_nat_irc
>
> echo "----------------------------------------------------------------------"
>
> # Just to be complete, here is a list of the remaining kernel modules
> # and their function. Please note that several modules should be only
> # loaded by the correct master kernel module for proper operation.
> # --------------------------------------------------------------------
> #
> # ipt_mark - this target marks a given packet for future action.
> # This automatically loads the ipt_MARK module
> #
> # ipt_tcpmss - this target allows to manipulate the TCP MSS
> # option for braindead remote firewalls.
> # This automatically loads the ipt_TCPMSS module
> #
> # ipt_limit - this target allows for packets to be limited to
> # to many hits per sec/min/hr
> #
> # ipt_multiport - this match allows for targets within a range
> # of port numbers vs. listing each port individually
> #
> # ipt_state - this match allows to catch packets with various
> # IP and TCP flags set/unset
> #
> # ipt_unclean - this match allows to catch packets that have invalid
> # IP/TCP flags set
> #
> # iptable_filter - this module allows for packets to be DROPped,
> # REJECTed, or LOGged. This module automatically
> # loads the following modules:
> #
> # ipt_LOG - this target allows for packets to be
> # logged
> #
> # ipt_REJECT - this target DROPs the packet and returns
> # a configurable ICMP packet back to the
> # sender.
> #
> # iptable_mangle - this target allows for packets to be manipulated
> # for things like the TCPMSS option, etc.
>
> echo ". Done loading modules."
>
>
>
> #CRITICAL: Enable IP forwarding since it is disabled by default since
> #
> # Redhat Users: you may try changing the options in
> # /etc/sysconfig/network from:
> #
> # FORWARD_IPV4=false
> # to
> # FORWARD_IPV4=true
> #
> echo " enabling forwarding.."
> echo "1" > /proc/sys/net/ipv4/ip_forward
>
>
> # Dynamic IP users:
> #
> # If you get your IP address dynamically from SLIP, PPP, or DHCP,
> # enable this following option. This enables dynamic-address hacking
> # which makes the life with Diald and similar programs much easier.
> #
> #echo " enabling DynamicAddr.."
> #echo "1" > /proc/sys/net/ipv4/ip_dynaddr
>
>
> # Enable simple IP forwarding and Masquerading
> #
> # NOTE: In IPTABLES speak, IP Masquerading is a form of SourceNAT or SNAT.
> #
> # NOTE #2: The following is an example for an internal LAN address in the
> # 192.168.0.x network with a 255.255.255.0 or a "24" bit subnet mask
> # connecting to the Internet on external interface "eth0". This
> # example will MASQ internal traffic out to the Internet but not
> # allow non-initiated traffic into your internal network.
> #
> #
> # ** Please change the above network numbers, subnet mask, and your
> # *** Internet connection interface name to match your setup
> #
>
>
> #Clearing any previous configuration
> #
> # Unless specified, the defaults for INPUT and OUTPUT is ACCEPT
> # The default for FORWARD is DROP
> #
> echo " clearing any existing rules and setting default policy.."
> $IPTABLES -P INPUT ACCEPT
> $IPTABLES -F INPUT
> $IPTABLES -P OUTPUT ACCEPT
> $IPTABLES -F OUTPUT
> $IPTABLES -P FORWARD DROP
> $IPTABLES -F FORWARD
> $IPTABLES -t nat -F
>
> echo " FWD: Allow all connections OUT and only existing and related ones IN"
> $IPTABLES -A FORWARD -i $EXTIF -o $INTIF -m state --state ESTABLISHED,RELATED -j ACCEPT
> $IPTABLES -A FORWARD -i $INTIF -o $EXTIF -j ACCEPT
> $IPTABLES -A FORWARD -j LOG
>
> echo " Enabling SNAT (MASQUERADE) functionality on $EXTIF"
> $IPTABLES -t nat -A POSTROUTING -o $EXTIF -j MASQUERADE
>
>
>
> echo -e "\nDone.\n"