System Administration Guide: IP Services

Managing Packet Filtering Rule Sets for Solaris IP Filter

When Solaris IP Filter is enabled, both active and inactive packet filtering rule sets can reside in the kernel. The active rule set determines what filtering is being done on incoming packets and outgoing packets. The inactive rule set also stores rules. These rules are not used unless you make the inactive rule set the active rule set. You can manage, view, and modify both active and inactive packet filtering rule sets.

ProcedureHow to View the Active Packet Filtering Rule Set

  1. Assume a role that includes the IP Filter Management rights profile, or become superuser.

    You can assign the IP Filter Management rights profile to a role that you create. To create the role and assign the role to a user, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

  2. View the active packet filtering rule set that is loaded in the kernel.


    # ipfstat -io
    

Example 25–1 Viewing the Active Packet Filtering Rule Set

The following example shows output from the active packet filtering rule set that is loaded in the kernel.


# ipfstat -io
empty list for ipfilter(out)
pass in quick on dmfe1 from 192.168.1.0/24 to any
pass in all
block in on dmfe1 from 192.168.1.10/32 to any

ProcedureHow to View the Inactive Packet Filtering Rule Set

  1. Assume a role that includes the IP Filter Management rights profile, or become superuser.

    You can assign the IP Filter Management rights profile to a role that you create. To create the role and assign the role to a user, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

  2. View the inactive packet filtering rule set.


    # ipfstat -I -io
    

Example 25–2 Viewing the Inactive Packet Filtering Rule Set

The following example shows output from the inactive packet filtering rule set.


# ipfstat -I -io
pass out quick on dmfe1 all
pass in quick on dmfe1 all

ProcedureHow to Activate a Different or Updated Packet Filtering Rule Set

Use the following procedure if you want to perform either of the following tasks:

  1. Assume a role that includes the IP Filter Management rights profile, or become superuser.

    You can assign the IP Filter Management rights profile to a role that you create. To create the role and assign the role to a user, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

  2. Choose one of the following steps:

    • Create a new rule set in a separate file of your choice if you want to activate an entirely different rule set.

    • Update the current rule set by editing the configuration file that contains that rule set.

  3. Remove the current rule set and load the new rule set.


    # ipf -Fa -f filename
    

    The filename can either be the new file with the new rule set or the updated file that contains the active rule set.

    The active rule set is removed from the kernel. The rules in the filename file become the active rule set.


    Note –

    You still need to issue the command even if you are reloading the current configuration file. Otherwise, the old rule set continues to be operative, and the modified rule set in the updated configuration file is not applied.

    Do not use commands such as ipf -D or svcadm restart to load the updated rule set. Such commands expose your network by disabling the firewall first before loading the new rule set.



Example 25–3 Activating a Different Packet Filtering Rule Set

The following example shows how to replace one packet filtering rule set with another packet filtering rule set in a separate configuration file, /etc/ipf/ipf.conf.


# ipfstat -io
empty list for ipfilter(out)
pass in quick on dmfe all
# ipf -Fa -f /etc/ipf/ipf.conf
# ipfstat -io
empty list for ipfilter(out)
block in log quick from 10.0.0.0/8 to any


Example 25–4 Reloading an Updated Packet Filtering Rule Set

The following example shows how to reload a packet filtering rule set that is currently active and which is then updated. In this example, the file in use is /etc/ipf/ipf.conf.


# ipfstat -io (Optional)
empty list for ipfilter (out)
block in log quick from 10.0.0.0/8 to any

(Edit the /etc/ipf/ipf.conf configuration file.)

# ip -Fa -f /etc/ipf/ipf.conf
# ipfstat -io (Optional)
empty list for ipfilter (out)
block in log quick from 10.0.0.0/8 to any
block in quick on elx10 from 192.168.0.0/12 to any

ProcedureHow to Remove a Packet Filtering Rule Set

  1. Assume a role that includes the IP Filter Management rights profile, or become superuser.

    You can assign the IP Filter Management rights profile to a role that you create. To create the role and assign the role to a user, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

  2. Remove the rule set.


    # ipf -F [a|i|o]
    
    -a

    Removes all filtering rules from the rule set.

    -i

    Removes the filtering rules for incoming packets.

    -o

    Removes the filtering rules for outgoing packets.


Example 25–5 Removing a Packet Filtering Rule Set

The following example shows how to remove all filtering rules from the active filtering rule set.


# ipfstat -io
block out log on dmf0 all
block in log quick from 10.0.0.0/8 to any
# ipf -Fa
# ipfstat -io
empty list for ipfilter(out)
empty list for ipfilter(in)

ProcedureHow to Append Rules to the Active Packet Filtering Rule Set

  1. Assume a role that includes the IP Filter Management rights profile, or become superuser.

    You can assign the IP Filter Management rights profile to a role that you create. To create the role and assign the role to a user, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

  2. Use one of the following methods to append rules to the active rule set:

    • Append rules to the rule set at the command line using the ipf -f - command.


      # echo "block in on dmfe1 proto tcp from 10.1.1.1/32 to any" | ipf -f -
      
    • Perform the following commands:

      1. Create a rule set in a file of your choice.

      2. Add the rules you have created to the active rule set.


        # ipf -f filename
        

        The rules in filename are added to the end of the active rule set. Because Solaris IP Filter uses a “last matching rule” algorithm, the added rules determine filtering priorities, unless you use the quick keyword. If the packet matches a rule containing the quick keyword, the action for that rule is taken, and no subsequent rules are checked.


Example 25–6 Appending Rules to the Active Packet Filtering Rule Set

The following example shows how to add a rule to the active packet filtering rule set from the command line.


# ipfstat -io
empty list for ipfilter(out)
block in log quick from 10.0.0.0/8 to any
# echo "block in on dmfe1 proto tcp from 10.1.1.1/32 to any" | ipf -f -
# ipfstat -io
empty list for ipfilter(out)
block in log quick from 10.0.0.0/8 to any
block in on dmfe1 proto tcp from 10.1.1.1/32 to any

ProcedureHow to Append Rules to the Inactive Packet Filtering Rule Set

  1. Assume a role that includes the IP Filter Management rights profile, or become superuser.

    You can assign the IP Filter Management rights profile to a role that you create. To create the role and assign the role to a user, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

  2. Create a rule set in a file of your choice.

  3. Add the rules you have created to the inactive rule set.


    # ipf -I -f filename
    

    The rules in filename are added to the end of the inactive rule set. Because Solaris IP Filter uses a “last matching rule” algorithm, the added rules determine filtering priorities, unless you use the quick keyword. If the packet matches a rule containing the quick keyword, the action for that rule is taken, and no subsequent rules are checked.


Example 25–7 Appending Rules to the Inactive Rule Set

The following example shows how to add a rule to the inactive rule set from a file.


# ipfstat -I -io
pass out quick on dmfe1 all
pass in quick on dmfe1 all
# ipf -I -f /etc/ipf/ipf.conf
# ipfstat -I -io
pass out quick on dmfe1 all
pass in quick on dmfe1 all
block in log quick from 10.0.0.0/8 to any

ProcedureHow to Switch Between Active and Inactive Packet Filtering Rule Sets

  1. Assume a role that includes the IP Filter Management rights profile, or become superuser.

    You can assign the IP Filter Management rights profile to a role that you create. To create the role and assign the role to a user, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

  2. Switch the active and inactive rule sets.


    # ipf -s
    

    This command enables you to switch between the active and inactive rule sets in the kernel. Note that if the inactive rule set is empty, there is no packet filtering.


Example 25–8 Switching Between the Active and Inactive Packet Filtering Rule Sets

The following example shows how using the ipf -s command results in the inactive rule set becoming the active rule set and the active rule set becoming the inactive rule set.


ProcedureHow to Remove an Inactive Packet Filtering Rule Set From the Kernel

  1. Assume a role that includes the IP Filter Management rights profile, or become superuser.

    You can assign the IP Filter Management rights profile to a role that you create. To create the role and assign the role to a user, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.

  2. Specify the inactive rule set in the “flush all” command.


    # ipf -I -Fa
    

    This command flushes the inactive rule set from the kernel.


    Note –

    If you subsequently run ipf -s, the empty inactive rule set will become the active rule set. An empty active rule set means that no filtering will be done.



Example 25–9 Removing an Inactive Packet Filtering Rule Set From the Kernel

The following example shows how to flush the inactive packet filtering rule set so that all rules have been removed.


# ipfstat -I -io
empty list for inactive ipfilter(out)
block in log quick from 10.0.0.0/8 to any
block in on dmfe1 proto tcp from 10.1.1.1/32 to any
# ipf -I -Fa
# ipfstat -I -io
empty list for inactive ipfilter(out)
empty list for inactive ipfilter(in)