When expiring a neighbour cache entry we may need to look up the associated
default router, which requires the nd6 read lock. To avoid an LOR, the nd6
lock should be acquired first.
X-MFC-With: r296063
Tested by: Larry Rosenman <ler@lerctr.org> (previous revision)
route caching for TCP, with some improvements. In particular, invalidate
the route cache if a new route is added, which might be a better match.
The cache is automatically invalidated if the old route is deleted.
Submitted by: Mike Karels
Reviewed by: gnn
Differential Revision: https://reviews.freebsd.org/D4306
Factor out nd6 and in6_attach initialization to their own files.
Also move destruction into those files though still called from
the central initialization.
Sponsored by: CK Software GmbH
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Reviewed by: gnn
Differential Revision: https://reviews.freebsd.org/D5033
This allows some simplification of its callers. No functional change
intended.
Tested by: Larry Rosenman (as part of a larger change)
MFC after: 1 month
pointer isn't NULL, it is safe, because we are handling IPV6_PKTINFO
socket option in this block of code. Also, use in6ifa_withaddr() instead
of ifa_withaddr().
The m_ext.ext_cnt pointer becomes a union. It can now hold the refcount
value itself. To tell that m_ext.ext_flags flag EXT_FLAG_EMBREF is used.
The first mbuf to attach a cluster stores the refcount. The further mbufs
to reference the cluster point at refcount in the first mbuf. The first
mbuf is freed only when the last reference is freed.
The benefit over refcounts stored in separate slabs is that now refcounts
of different, unrelated mbufs do not share a cache line.
For EXT_EXTREF mbufs the zone_ext_refcnt is no longer needed, and m_extadd()
becomes void, making widely used M_EXTADD macro safe.
For EXT_SFBUF mbufs the sf_ext_ref() is removed, which was an optimization
exactly against the cache aliasing problem with regular refcounting.
Discussed with: rrs, rwatson, gnn, hiren, sbruno, np
Reviewed by: rrs
Differential Revision: https://reviews.freebsd.org/D5396
Sponsored by: Netflix
This addresses a number of race conditions that can cause crashes as a
result of unsynchronized access to the list.
PR: 206904
Tested by: Larry Rosenman <ler@lerctr.org>,
Kevin Bowling <kevin.bowling@kev009.com>
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D5315
Fix a panic that occurs when a vnet interface is unavailable at the time the
vnet jail referencing said interface is stopped.
Sponsored by: FIS Global, Inc.
back and harmize the use cases among RIB, IPFW, PF yet but it's also not
the scope of this work. Prevents instant panics on teardown and frees
the FIB bits again.
Sponsored by: The FreeBSD Foundation
There are number of radix consumers in kernel land (pf,ipfw,nfs,route)
with different requirements. In fact, first 3 don't have _any_ requirements
and first 2 does not use radix locking. On the other hand, routing
structure do have these requirements (rnh_gen, multipath, custom
to-be-added control plane functions, different locking).
Additionally, radix should not known anything about its consumers internals.
So, radix code now uses tiny 'struct radix_head' structure along with
internal 'struct radix_mask_head' instead of 'struct radix_node_head'.
Existing consumers still uses the same 'struct radix_node_head' with
slight modifications: they need to pass pointer to (embedded)
'struct radix_head' to all radix callbacks.
Routing code now uses new 'struct rib_head' with different locking macro:
RADIX_NODE_HEAD prefix was renamed to RIB_ (which stands for routing
information base).
New net/route_var.h header was added to hold routing subsystem internal
data. 'struct rib_head' was placed there. 'struct rtentry' will also
be moved there soon.
easier. Note: this is currently not in a usable state as certain
teardown parts are not called and the DOMAIN rework is missing.
More to come soon and find its way to head.
Obtained from: P4 //depot/user/bz/vimage/...
Sponsored by: The FreeBSD Foundation
The sctp6_ctlinput() function does not properly check the length of the packet
it receives from the ICMP6 input routine. This means that an attacker can craft
a packet that will cause a kernel panic.
When the kernel receives an ICMP6 error message with one of the types/codes
it handles, it calls icmp6_notify_error() to deliver it to the upper-level
protocol. icmp6_notify_error() cycles through the extension headers (if any)
to find the protocol number of the first non-extension header. It does NOT
verify the length of the non-extension header.
It passes information about the packet (including the actual packet) to the
upper-level protocol's pr_ctlinput function. In the case of SCTP for IPv6,
icmp6_notify_error() calls sctp6_ctlinput().
sctp6_ctlinput() assumes that the incoming packet contains a sufficiently-long
SCTP header and calls m_copydata() to extract a copy of that header. In turn,
m_copydata() assumes that the caller has already verified that the offset and
length parameters are correct. If they are incorrect, it will dereference a
NULL pointer and cause a kernel panic.
In short, no one is sufficiently verifying the input, and the result is a
kernel panic.
Submitted by: jtl
Security: SA-16:01.sctp
Move actual rte selection process from rtalloc_mpath_fib()
to the rt_path_selectrte() function. Add public
rt_mpath_select() to use in fibX_lookup_ functions.
in6_selectsrc() has 2 class of users: socket-based one (raw/udp/pcb/etc) and
socket-less (ND code). The main reason for that change is inability to
specify non-default FIB for callers w/o socket since (internally) inpcb
is used to determine fib.
As as result, add 2 wrappers for in6_selectsrc() (making in6_selectsrc()
static):
1) in6_selectsrc_socket() for the former class. Embed scope_ambiguous check
along with returning hop limit when needed.
2) in6_selectsrc_addr() for the latter case. Add 'fibnum' argument and
pass IPv6 address w/ explicitly specified scope as separate argument.
Reviewed by: ae (previous version)
This check was added in initial? netinet6/ import
back in 1999 (r53541).
It effectively became unnecessary after 'address/prefix clean-ups'
KAME commit 90ff8792e676132096a440dd787f99a5a5860ee8 (github) in 2001
(merged to FreeBSD in r78064) where prefix check was added to
nd6_prefix_onlink(). Similar IPv4 check (in_addroute() was added
in r137628).
Additionally, the right plance for this (or similar) check is the prefix
addition code (nd6_prefix_onlink(), nd6_prefix_onlink_rtrequest(),
in_addprefix() or rtinit()), but not the generic radix insert routine.
entries data in unified format.
There are control plane functions that require information other than
just next-hop data (e.g. individual rtentry fields like flags or
prefix/mask). Given that the goal is to avoid rte reference/refcounting,
re-use rt_addrinfo structure to store most rte fields. If caller wants
to retrieve key/mask or gateway (which are sockaddrs and are allocated
separately), it needs to provide sufficient-sized sockaddrs structures
w/ ther pointers saved in passed rt_addrinfo.
Convert:
* lltable new records checks (in_lltable_rtcheck(),
nd6_is_new_addr_neighbor().
* rtsock pre-add/change route check.
* IPv6 NS ND-proxy check (RADIX_MPATH code was eliminated because
1) we don't support RTF_ANNOUNCE ND-proxy for networks and there should
not be multiple host routes for such hosts 2) if we have multiple
routes we should inspect them (which is not done). 3) the entire idea
of abusing KRT as storage for ND proxy seems odd. Userland programs
should be used for that purpose).
in6_selectif().
The main task of in6_selectsrc() is to return IPv6 SAS (along with
output interface used for scope checks). No data-path code uses
route argument for caching. The only users are icmp6 (reflect code),
ND6 ns/na generation code. All this fucntions are control-plane, so
there is no reason to try to 'optimize' something by passing cached
route into to ip6_output(). Given that, simplify code by eliminating
in6_selectsrc() 'struct route_in6' argument. Since in6_selectif() is
used only by in6_selectsrc(), eliminate its 'struct route_in6' argument,
too. While here, reshape rte-related code inside in6_selectif() to
free lookup result immediately after saving all the needed fields.
Add ro_mtu field to 'struct route' to be able to pass lookup MTU back to
the caller.
Currently, ip6_getpmtu() has 2 totally different use cases:
1) control plane (IPV6_PATHMTU req), where we just need to calculate MTU
and return it, w/o any reusability.
2) Actual ip6_output() data path where we (nearly) always use the provided
route lookup data. If this data is not 'valid' we need to perform another
lookup and save the result (which cannot be re-used by ip6_output()).
Given that, handle 1) by calling separate function doing rte lookup itself.
Resulting MTU is calculated by (newly-added) ip6_calcmtu() used by both
ip6_getpmtu_ctl() and ip6_getpmtu().
For 2) instead of storing ref'ed rte, store mtu (the only needed data
from the lookup result) inside newly-added ro_mtu field.
'struct route' was shrinked by 8(or 4 bytes) in r292978. Grow it again
by 4 bytes. New ro_mtu field will be used in other places like
ip/tcp_output (EMSGSIZE handling from output routines).
Reviewed by: ae
Add if_requestencap() interface method which is capable of calculating
various link headers for given interface. Right now there is support
for INET/INET6/ARP llheader calculation (IFENCAP_LL type request).
Other types are planned to support more complex calculation
(L2 multipath lagg nexthops, tunnel encap nexthops, etc..).
Reshape 'struct route' to be able to pass additional data (with is length)
to prepend to mbuf.
These two changes permits routing code to pass pre-calculated nexthop data
(like L2 header for route w/gateway) down to the stack eliminating the
need for other lookups. It also brings us closer to more complex scenarios
like transparently handling MPLS nexthops and tunnel interfaces.
Last, but not least, it removes layering violation introduced by flowtable
code (ro_lle) and simplifies handling of existing if_output consumers.
ARP/ND changes:
Make arp/ndp stack pre-calculate link header upon installing/updating lle
record. Interface link address change are handled by re-calculating
headers for all lles based on if_lladdr event. After these changes,
arpresolve()/nd6_resolve() returns full pre-calculated header for
supported interfaces thus simplifying if_output().
Move these lookups to separate ether_resolve_addr() function which ether
returs error or fully-prepared link header. Add <arp|nd6_>resolve_addr()
compat versions to return link addresses instead of pre-calculated data.
BPF changes:
Raw bpf writes occupied _two_ cases: AF_UNSPEC and pseudo_AF_HDRCMPLT.
Despite the naming, both of there have ther header "complete". The only
difference is that interface source mac has to be filled by OS for
AF_UNSPEC (controlled via BIOCGHDRCMPLT). This logic has to stay inside
BPF and not pollute if_output() routines. Convert BPF to pass prepend data
via new 'struct route' mechanism. Note that it does not change
non-optimized if_output(): ro_prepend handling is purely optional.
Side note: hackish pseudo_AF_HDRCMPLT is supported for ethernet and FDDI.
It is not needed for ethernet anymore. The only remaining FDDI user is
dev/pdq mostly untouched since 2007. FDDI support was eliminated from
OpenBSD in 2013 (sys/net/if_fddisubr.c rev 1.65).
Flowtable changes:
Flowtable violates layering by saving (and not correctly managing)
rtes/lles. Instead of passing lle pointer, pass pointer to pre-calculated
header data from that lle.
Differential Revision: https://reviews.freebsd.org/D4102
the wrapper functions as used in r252511. We can directly use the
locking macros.
Reviewed by: jtl, rwatson
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D4731
bridge(4) interfaces have an if_type of IFT_BRIDGE, rather than
IFT_ETHER, even though they only support Ethernet-style links. This
caused in6_if2idlen to emit an "unknown link type (209)" warning to
the console every time it was called. Add IFT_BRIDGE to the case
statement in the appropriate place, indicating that it uses the same
IPv6 address format as other Ethernet-like interfaces.
MFC after: 1 week
Reported by: Matthew D. Fuller (fullermd over-yonder.net),
Kevin Bowling (kevin.bowling kev009.com)
MFC after: 13 days
X-MFC with: r292601
Sponsored by: The FreeBSD Foundation
on vnet enabled jail shutdown. Call the provided cleanup
routines for IP versions 4 and 6 to plug these leaks.
Sponsored by: The FreeBSD Foundation
MFC atfer: 2 weeks
Reviewed by: gnn
Differential Revision: https://reviews.freebsd.org/D4530
