optimization made last year. should solve PR 17867 and 10195.
IP_HDRINCL behavior of raw ip socket is kept unchanged. we may want to
provide IP_HDRINCL variant that does not swap endian.
as necessary:
* Implement a new mbuf utility routine, m_copyup(), is is like
m_pullup(), except that it always prepends and copies, rather
than only doing so if the desired length is larger than m->m_len.
m_copyup() also allows an offset into the destination mbuf, which
allows space for packet headers, in the forwarding case.
* Add *_HDR_ALIGNED_P() macros for IP, IPv6, ICMP, and IGMP. These
macros expand to 1 if __NO_STRICT_ALIGNMENT is defined, so that
architectures which do not have strict alignment constraints don't
pay for the test or visit the new align-if-needed path.
* Use the new macros to check if a header needs to be aligned, or to
assert that it already is, as appropriate.
Note: This code is still somewhat experimental. However, the new
code path won't be visited if individual device drivers continue
to guarantee that packets are delivered to layer 3 already properly
aligned (which are rules that are already in use).
benefit currently). Rework tcp_reass code to optimize the 4 most likely causes
of out-of-order packets: first OoO pkt, next OoO pkt in seq, OoO pkt is part
of new chuck of OoO packets, and the OoO pkt fills the first hole. Add evcnts
to instrument tcp_reass (enabled by the options TCP_REASS_COUNTERS). This is
part 1/2 of tcp_reass changes.
deal with shortages of the VM maps where the backing pages are mapped
(usually kmem_map). Try to deal with this:
* Group all information about the backend allocator for a pool in a
separate structure. The pool references this structure, rather than
the individual fields.
* Change the pool_init() API accordingly, and adjust all callers.
* Link all pools using the same backend allocator on a list.
* The backend allocator is responsible for waiting for physical memory
to become available, but will still fail if it cannot callocate KVA
space for the pages. If this happens, carefully drain all pools using
the same backend allocator, so that some KVA space can be freed.
* Change pool_reclaim() to indicate if it actually succeeded in freeing
some pages, and use that information to make draining easier and more
efficient.
* Get rid of PR_URGENT. There was only one use of it, and it could be
dealt with by the caller.
From art@openbsd.org.
Don't copy ttl from the inner packet to the encapsulating packet. Make
the outer ttl sysctl'able. This should close PR 14269 from Jasper Wallace
(change partly from there) and it makes traceroute work over gre tunnels.
Add capabilities bits that indicate an interface can only perform
in-bound TCPv4 or UDPv4 checksums. There is at least one Gig-E chip
for which this is true (Level One LXT-1001), and this is also the
case for the Intel i82559 10/100 Ethernet chips.
network interfaces. This works by pre-computing the pseudo-header
checksum and caching it, delaying the actual checksum to ip_output()
if the hardware cannot perform the sum for us. In-bound checksums
can either be fully-checked by hardware, or summed up for final
verification by software. This method was modeled after how this
is done in FreeBSD, although the code is significantly different in
most places.
We don't delay checksums for IPv6/TCP, but we do take advantage of the
cached pseudo-header checksum.
Note: hardware-assisted checksumming defaults to "off". It is
enabled with ifconfig(8). See the manual page for details.
Implement hardware-assisted checksumming on the DP83820 Gigabit Ethernet,
3c90xB/3c90xC 10/100 Ethernet, and Alteon Tigon/Tigon2 Gigabit Ethernet.
"lots of fragmented packets" DoS attack.
the current default value is derived from ipv6 counterpart, which is
a magical value "200". it should be enough for normal systems, not sure
if it is enough when you take hundreds of thousands of tcp connections on
your system. if you have proposal for a better value with concrete reasons,
let me know.
- let ipfilter look at wire-format packet only (not the decapsulated ones),
so that VPN setting can work with NAT/ipfilter settings.
sync with kame.
TODO: use header history for stricter inbound validation
"key" and a "dlt", use a "type" (PFIL_TYPE_{AF,IFNET} for now) and
a val/ptr appropriate for that type. This allows for more future
flexibility with the pfil_hook mechanism.
- All packets are passed to PFIL_HOOKS as they come off the wire, i.e.
fields in protocol headers in network order, etc.
- Allow for multiple hooks to be registered, using a "key" and a "dlt".
The "dlt" is a BPF data link type, indicating what type of header is
present.
- INET and INET6 register with key == AF_INET or AF_INET6, and
dlt == DLT_RAW.
- PFIL_HOOKS now take an argument for the filter hook, and mbuf **,
an ifnet *, and a direction (PFIL_IN or PFIL_OUT), thus making them
less IP (really, IP Filter) centric.
Maintain compatibility with IP Filter by adding wrapper functions for
IP Filter.
correct timestamp option validation (len and ptr upper/lower bound
based on RFC791).
fill "pointer" field for parameter problem in timestamp option processing.
