sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.
- introduce a limit for the routes accepted via IPv6 Router Advertisement:
a common 2 interface client will have 6, the default limit is 100 and
can be adjusted via sysctl
- report the current number of routes installed via RA via sysctl
- count discarded route additions. Note that one RA message is two routes.
This is at present only across all interfaces even though per-interface
would be more useful, since the per-interface structure complies to RFC2466
- bump kernel version due to the previous change
- adjust netstat to use the new value (with netstat -p icmp6)
methods called Vestigial Time-Wait (VTW) and Maximum Segment Lifetime
Truncation (MSLT).
MSLT and VTW were contributed by Coyote Point Systems, Inc.
Even after a TCP session enters the TIME_WAIT state, its corresponding
socket and protocol control blocks (PCBs) stick around until the TCP
Maximum Segment Lifetime (MSL) expires. On a host whose workload
necessarily creates and closes down many TCP sockets, the sockets & PCBs
for TCP sessions in TIME_WAIT state amount to many megabytes of dead
weight in RAM.
Maximum Segment Lifetimes Truncation (MSLT) assigns each TCP session to
a class based on the nearness of the peer. Corresponding to each class
is an MSL, and a session uses the MSL of its class. The classes are
loopback (local host equals remote host), local (local host and remote
host are on the same link/subnet), and remote (local host and remote
host communicate via one or more gateways). Classes corresponding to
nearer peers have lower MSLs by default: 2 seconds for loopback, 10
seconds for local, 60 seconds for remote. Loopback and local sessions
expire more quickly when MSLT is used.
Vestigial Time-Wait (VTW) replaces a TIME_WAIT session's PCB/socket
dead weight with a compact representation of the session, called a
"vestigial PCB". VTW data structures are designed to be very fast and
memory-efficient: for fast insertion and lookup of vestigial PCBs,
the PCBs are stored in a hash table that is designed to minimize the
number of cacheline visits per lookup/insertion. The memory both
for vestigial PCBs and for elements of the PCB hashtable come from
fixed-size pools, and linked data structures exploit this to conserve
memory by representing references with a narrow index/offset from the
start of a pool instead of a pointer. When space for new vestigial PCBs
runs out, VTW makes room by discarding old vestigial PCBs, oldest first.
VTW cooperates with MSLT.
It may help to think of VTW as a "FIN cache" by analogy to the SYN
cache.
A 2.8-GHz Pentium 4 running a test workload that creates TIME_WAIT
sessions as fast as it can is approximately 17% idle when VTW is active
versus 0% idle when VTW is inactive. It has 103 megabytes more free RAM
when VTW is active (approximately 64k vestigial PCBs are created) than
when it is inactive.
will have an easier time replacing it with something different, even if
it is a second radix-trie implementation.
sys/net/route.c and sys/net/rtsock.c no longer operate directly on
radix_nodes or radix_node_heads.
Hopefully this will reduce the temptation to implement multipath or
source-based routing using grotty hacks to the grotty old radix-trie
code, too. :-)
with an uninitialized struct ip6_pktopts on the stack, opt.
ip6_clearpktopts(&opt, ...) could dereference dangling pointers,
leading to memory corruption or a crash. Now, udp6_output() calls
ip6_clearpktopts(&opt, ...) only if opt was initialized. Thanks to
Clement LECIGNE for reporting this bug.
Fix a potential memory leak: it is udp6_output()'s responsibility
to free its mbuf arguments on error. In the unlikely event that
sa6_embedscope() failed, udp6_output() would not free its mbuf
arguments.
I will ask for this to be pulled up to -4, -5, and -5-0.
nd6_storelladdr: sdl_alen == 0, dst=... if=wm1", add printfs for some
"impossible" conditions, and make the nd6_storelladdr() printf more
informative by printing the value of sdl_alen.
#if NBPFILTER is no longer required in the client. This change
doesn't yet add support for loading bpf as a module, since drivers
can register before bpf is attached. However, callers of bpf can
now be modularized.
Dynamically loadable bpf could probably be done fairly easily with
coordination from the stub driver and the real driver by registering
attachments in the stub before the real driver is loaded and doing
a handoff. ... and I'm not going to ponder the depths of unload
here.
Tested with i386/MONOLITHIC, modified MONOLITHIC without bpf and rump.
Many drivers set the UDP/TCP v4 flags even for v6 traffic and if the
packet is encapsulated with gif, the IPv6 header would get corrupted by
ip_output. Patch suggested by bad@
Add a flag ND6_IFF_OVERRIDE_RTADV that tells the kernel to override
ip6_accept_rtadv (net.inet6.ip6.accept_rtadv) on an interface.
Add a routine nd6_accepts_rtadv(ndi) that evaluates both the flags
on the interface represented by ndi and ip6_accept_rtadv, and
returns 'true' if the given interface should accept Router
Advertisements, and 'false' if not.
Now, ND6_IFF_ACCEPT_RTADV works as it was historically documented:
if it is set, then accept router advertisements iff ip6_accept_rtadv
!= 0. Otherwise, do not accept router advertisements.
If ND6_IFF_OVERRIDE_RTADV is set, then the flag ND6_IFF_ACCEPT_RTADV
overrides ip6_accept_rtadv: if ND6_IFF_ACCEPT_RTADV is set, accept;
otherwise reject. Ignore ip6_accept_rtadv.
If neither ND6_IFF_ACCEPT_RTADV nor ND6_IFF_OVERRIDE_RTADV is set,
reject Router Advertisements.
for arg and gre because they cause a race condition by calling ioctl() during
interface initialization. To make this work correctly we would need to
synchronize all interface init routines.
addresses. Make the kernel support SIOC[SG]IFADDRPREF for IPv6
interface addresses.
In in6ifa_ifpforlinklocal(), consult preference numbers before
making an otherwise arbitrary choice of in6_ifaddr. Otherwise,
preference numbers are *not* consulted by the kernel, but that will
be rather easy for somebody with a little bit of free time to fix.
Please note that setting the preference number for a link-local
IPv6 address does not work right, yet, but that ought to be fixed
soon.
In support of the changes above,
1 Add a method to struct domain for "externalizing" a sockaddr, and
provide an implementation for IPv6. Expect more work in this area: it
may be more proper to say that the IPv6 implementation "internalizes"
a sockaddr. Add sockaddr_externalize().
2 Add a subroutine, sofamily(), that returns a struct socket's address
family or AF_UNSPEC.
3 Make a lot of IPv4-specific code generic, and move it from
sys/netinet/ to sys/net/ for re-use by IPv6 parts of the kernel and
ifconfig(8).
to an interface. This keeps the kernel from entering ifp->if_ioctl
recursively, which can deadlock if if_ioctl takes locks. This will
fix deadlocks & LOCKDEBUG errors in agr(4) (kern/39940) and in
gre(4).
christos