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.
(reported by: grendel@heorot.stanford.edu (Ted U)
- Don't cast malloc/realloc/calloc return values because they hide LP64 bugs.
- Don't destroy the whole array when realloc fails
- Use calloc in all cases (malloc was used inconsistently).
- Avoid duplicating code.
Reviewed by: ross
"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.
fails, return EIO instead.
- iplioctl(): If performing a NAT operation, and IP Filter is not
yet initialized (e.g. by `ipf -E'), enable it implicitly before
doing the NAT operation.
timeout()/untimeout() API:
- Clients supply callout handle storage, thus eliminating problems of
resource allocation.
- Insertion and removal of callouts is constant time, important as
this facility is used quite a lot in the kernel.
The old timeout()/untimeout() API has been removed from the kernel.
between protocol handlers.
ipsec socket pointers, ipsec decryption/auth information, tunnel
decapsulation information are in my mind - there can be several other usage.
at this moment, we use this for ipsec socket pointer passing. this will
avoid reuse of m->m_pkthdr.rcvif in ipsec code.
due to the change, MHLEN will be decreased by sizeof(void *) - for example,
for i386, MHLEN was 100 bytes, but is now 96 bytes.
we may want to increase MSIZE from 128 to 256 for some of our architectures.
take caution if you use it for keeping some data item for long period
of time - use extra caution on M_PREPEND() or m_adj(), as they may result
in loss of m->m_pkthdr.aux pointer (and mbuf leak).
this will bump kernel version.
(as discussed in tech-net, tested in kame tree)
pfil information, instead, struct protosw now contains a structure
which caontains list heads, etc. The per-protosw pfil struct is passed
to pfil_hook_get(), along with an in/out flag to get the head of the
relevant filter list. This has been done for only IPv4 and IPv6, at
present, with these patches only enabling filtering for IPPROTO_IP and
IPPROTO_IPV6, although it is possible to have tcp/udp, etc, dedicated
filters now also. The ipfilter code has been updated to only filter
IPv4 packets - next major release of ipfilter is required for ipv6.
back into the packet. (ip_output() clears it since ipsec reuses that
packet field in the output path. by putting it back, we're going to
pretend we're back on the input path now).
the member is used to pass struct socket to ip{,6}_output for ipsec decisions.
(i agree it is kind of ugly. we need to modify struct mbuf if we are
to do better - which seems to me a bit too much)
operation, since:
- in ipl_enable(), "fr_savep = fr_checkp" is not conditionalized
in the same way (not at all), and
- without this change, it was not possible to enable, disable,
and reenable ipfilter.
