Darren Reed hosszú csipkerózsika álmából magához térve bejelentette az IP Filter következő, 4.1-es verzióját.
Aki követte az IPF fejlődését, tudhatja, hogy Darren, még az OpenBSD pf megjelenése előtt nagyon ígérgette a redundáns működést, amelyről azóta nem igen lehetett hallani.
A 4-es verzióban úgy tűnik ez a funkció is működőképes már. A másik meglepetés az, hogy Darren szerint hamarosan elérhető lesz programja Linuxra is.Újdonságok a 3.x-es szériához képest:
Administration:
- Run-time support for modifying ipf table size parameters.
- Run-time support for tuning other ipfilter parameters.
Content Scanning:
- Simple matching of content for TCP session startup.
Firewall Synchronising:
- Master/slave programs available.
General:
- All input files allow simple 'macro' definitions and expansion,
including nesting.
- Code has been rototilled to make maintenance and enhancements
eaiser for me and you.
- More configuration files and binaries.
- Takes up more memory.
- Probably slower.
- Versioned API to support changes in the ABI without breaking
existing binaries (4.0 onward only.)
- IP-Filter framework in place for handling multiple different
types of packet matching for firewalling.
- IP Id number rewriting available.
- Verification of checksums for recognised packet types.
- Optionally enable/disable IP forwarding when enabled/disabled.
IPF:
- BPF syntax available for matching packets in ipf rules (1).
- Can convert IPv4 ipf rules into C code and either:
* load them as an LKM o;
* compile them statically into the kernel (where possible.)
- Address pools allow for simpler rules covering large numbers of
addresses/networks (IPv4 only).
- Lookup functions available to map an IPv4 address to a group.
- Groups can be referenced by multiple heads for subroutine-like use.
- NAT/ipf rules can refer to each other via a tag, creating an implied
join that forms part of the packet matching.
- Extra packet attributes available for filter rules:
* source address/routing interface mismatch;
* multicast (3);
* broadcast (2,3);
* state lookup partially failed;
* out of the TCP window for a state connection;
* NAT lookup partially failed.
- PPS (packets per second) matching available for ipf rules.
- Rule collections (cf FreeBSD numbering) supported for ipf rules.
- Groups can now be names rather than just numbers
IPV6:
- understands extension headers.
- can filter on extension headers.
Logging:
- ipmon now comes with a configuration file for more advanced logging
behaviour.
- Can append arbitrary logging tags with ipf rules for easy matching.
NAT:
- "sticky" mapping available to ensure an address translation on
a per-address basis is always the same (while known) for a set
IP address.
Operating System Support:
- HP-UX 11 added.
- Tru64 5.1a added.
- Solaris/HP-UX now use pfil STREAMS module.
- Linux 2.4 on the way.
Proxies:
- PPTP proxy added.
- IRC proxy added.
- RPCBIND proxy added.
- FTP proxy support for EPSV (IPv4 only.)
Stateful Inspection:
- Can insist that all TCP data arrives in order.
- Can insist that all fragments pass through in order.
- The number of states created per-rule can be set where the total
across all rules may exceed the maximum allowed.
- Can elect not to automatically match ICMP error packets.
- TCP sequence number rewriting supported.