netinet: add a probe point for IP, IP6, ICMP, ICMP6, UDP and TCP stats counters

When debugging network issues one common clue is an unexpectedly
incrementing error counter. This is helpful, in that it gives us an
idea of what might be going wrong, but often these counters may be
incremented in different functions.

Add a static probe point for them so that we can use dtrace to get
futher information (e.g. a stack trace).

For example:
dtrace -n 'mib:ip:count: { printf("%d", arg0); stack(); }'

This can be disabled by setting the following kernel option:
options KDTRACE_NO_MIB_SDT

Reviewed by: gallatin, tuexen (previous version), gnn (previous version)
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D43504

icmp6: move ICMPv6 related tunables to the files where they are used

Most of them can be declared as static after the move out of in6_proto.c.
Keeping sysctl(9) declarations with their text descriptions next to the
variable declaration create self-documenting code. There should be no
functional changes.

Differential Revision: https://reviews.freebsd.org/D44481

ip6_output: Reduce cache misses on pktopts

When profiling an IP6 heavy workload, I noticed that we were
getting a lot of cache misses in ip6_output() around
ip6_pktopts. This was happening because the TCP stack passes
inp->in6p_outputopts even if all options are unused. So in the
common case of no options present, pkt_opts is not null, and is
checked repeatedly for different options. Since ip6_pktopts is
large (4 cachelines), and every field is checked, we take 4
cache misses (2 of which tend to be hidden by the adjacent line
prefetcher).

To fix this common case, I introduced a new flag in ip6_pktopts
(ip6po_valid) which tracks which options have been set. In the
common case where nothing is set, this causes just a single
cache miss to load. It also eliminates a test for some options
(if (opt != NULL && opt->val >= const) vs if ((optvalid & flag) !=0 )

To keep the struct the same size in 64-bit kernels, and to keep
the integer values (like ip6po_hlim, ip6po_tclass, etc) on the
same cacheline, I moved them to the top.

As suggested by zlei, the null check in MAKE_EXTHDR() becomes
redundant, and can be removed.

For our web server workload (with the ip6po_tclass option set),
this drops the CPI from 2.9 to 2.4 for ip6_output

Differential Revision: https://reviews.freebsd.org/D44204
Reviewed by: bz, glebius, zlei
No Objection from: melifaro
Sponsored by: Netflix Inc.

sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

sys: Remove $FreeBSD$: one-line .h pattern

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

Fix MINIMAL build

Pre-declare struct ucred, to fix build issues on the MINIMAL config:

In file included from /usr/src/sys/netpfil/pf/pfsync_nv.c:40:
/usr/src/sys/netinet6/ip6_var.h:384:31: error: declaration of 'struct ucred' will not be visible outside of this function [-Werror,-Wvisibility]
struct ip6_pktopts *, struct ucred *, int);
^
/usr/src/sys/netinet6/ip6_var.h:408:28: error: declaration of 'struct ucred' will not be visible outside of this function [-Werror,-Wvisibility]
struct inpcb *, struct ucred *, int, struct in6_addr *, int *);
^
2 errors generated.

netinet6: make IPv6 fragment TTL per-VNET configurable.

Having it configurable adds more flexibility, especially
for the systems with low amount of memory.
Additionally, it allows to speedup frag6/ tests execution.

Reviewed by: kp, markj, bz
Differential Revision: https://reviews.freebsd.org/D35755
MFC after: 2 weeks

netinet*: Fix redirects for connections from localhost

Redirect rules use PFIL_IN and PFIL_OUT events to allow packet filter
rules to change the destination address and port for a connection.
Typically, the rule triggers on an input event when a packet is received
by a router and the destination address and/or port is changed to
implement the redirect. When a reply packet on this connection is output
to the network, the rule triggers again, reversing the modification.

When the connection is initiated on the same host as the packet filter,
it is initially output via lo0 which queues it for input processing.
This causes an input event on the lo0 interface, allowing redirect
processing to rewrite the destination and create state for the
connection. However, when the reply is received, no corresponding output
event is generated; instead, the packet is delivered to the higher level
protocol (e.g. tcp or udp) without reversing the redirect, the reply is
not matched to the connection and the packet is dropped (for tcp, a
connection reset is also sent).

This commit fixes the problem by adding a second packet filter call in
the input path. The second call happens right before the handoff to
higher level processing and provides the missing output event to allow
the redirect's reply processing to perform its rewrite. This extra
processing is disabled by default and can be enabled using pfilctl:

pfilctl link -o pf:default-out inet-local
pfilctl link -o pf:default-out6 inet6-local

PR: 268717
Reviewed-by: kp, melifaro
MFC-after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D40256

net.inet6.ip6.log_interval: use ppsratecheck(9) internally

Reported by: mjg
Differential Revision: https://reviews.freebsd.org/D38758

netinet6: allow disabling excess log messages

RFC 4443 specifies cases where certain packets, like those originating from
local-scope addresses destined outside of the scope shouldn't be forwarded.
The current practice is to drop them, send ICMPv6 message where appropriate,
and log the message:

cannot forward src fe80:10::426:82ff:fe36:1d8, dst 2001:db8:db8::10, nxt
58, rcvif vlan5, outif vlan2

At times the volume of such messages cat get very high. Let's allow local
admins to disable such messages on per vnet basis, keeping the current
default (log).

Reported by: zarychtam@plan-b.pwste.edu.pl
Reviewed by: zlei (previous version), pauamma (docs)
Differential Revision: https://reviews.freebsd.org/D38644

netinet*: remove PRC_ constants and streamline ICMP processing

In the original design of the network stack from the protocol control
input method pr_ctlinput was used notify the protocols about two very
different kinds of events: internal system events and receival of an
ICMP messages from outside. These events were coded with PRC_ codes.
Today these methods are removed from the protosw(9) and are isolated
to IPv4 and IPv6 stacks and are called only from icmp*_input(). The
PRC_ codes now just create a shim layer between ICMP codes and errors
or actions taken by protocols.

- Change ipproto_ctlinput_t to pass just pointer to ICMP header. This
allows protocols to not deduct it from the internal IP header.
- Change ip6proto_ctlinput_t to pass just struct ip6ctlparam pointer.
It has all the information needed to the protocols. In the structure,
change ip6c_finaldst fields to sockaddr_in6. The reason is that
icmp6_input() already has this address wrapped in sockaddr, and the
protocols want this address as sockaddr.
- For UDP tunneling control input, as well as for IPSEC control input,
change the prototypes to accept a transparent union of either ICMP
header pointer or struct ip6ctlparam pointer.
- In icmp_input() and icmp6_input() do only validation of ICMP header and
count bad packets. The translation of ICMP codes to errors/actions is
done by protocols.
- Provide icmp_errmap() and icmp6_errmap() as substitute to inetctlerrmap,
inet6ctlerrmap arrays.
- In protocol ctlinput methods either trust what icmp_errmap() recommend,
or do our own logic based on the ICMP header.

Differential revision: https://reviews.freebsd.org/D36731

netinet*: de-void control input IP protocol methods

After decoupling of protosw(9) and IP wire protocols in 78b1fc05b205 for
IPv4 we got vector ip_ctlprotox[] that is executed only and only from
icmp_input() and respectively for IPv6 we got ip6_ctlprotox[] executed
only and only from icmp6_input(). This allows to use protocol specific
argument types in these methods instead of struct sockaddr and void.

Reviewed by: melifaro
Differential revision: https://reviews.freebsd.org/D36727

netinet6: retire ip6protosw.h

The netinet/ipprotosw.h and netinet6/ip6protosw.h were KAME relics, with
the former removed in f0ffb944d25 in 2001 and the latter survived until
today. It has been reduced down to only one useful declaration that
moves to ip6_var.h

Reviewed by: melifaro
Differential revision: https://reviews.freebsd.org/D36726

netinet*: move ipproto_register() and co to ip_var.h and ip6_var.h

This is a FreeBSD KPI and belongs to private header not netinet/in.h.

Reviewed by: melifaro
Differential revision: https://reviews.freebsd.org/D36723

frag6: use callout(9) directly instead of pr_slowtimo

Reviewed by: melifaro
Differential revision: https://reviews.freebsd.org/D36162

protosw: separate pr_input and pr_ctlinput out of protosw

The protosw KPI historically has implemented two quite orthogonal
things: protocols that implement a certain kind of socket, and
protocols that are IPv4/IPv6 protocol. These two things do not
make one-to-one correspondence. The pr_input and pr_ctlinput methods
were utilized only in IP protocols. This strange duality required
IP protocols that doesn't have a socket to declare protosw, e.g.
carp(4). On the other hand developers of socket protocols thought
that they need to define pr_input/pr_ctlinput always, which lead to
strange dead code, e.g. div_input() or sdp_ctlinput().

With this change pr_input and pr_ctlinput as part of protosw disappear
and IPv4/IPv6 get their private single level protocol switch table
ip_protox[] and ip6_protox[] respectively, pointing at array of
ipproto_input_t functions. The pr_ctlinput that was used for
control input coming from the network (ICMP, ICMPv6) is now represented
by ip_ctlprotox[] and ip6_ctlprotox[].

ipproto_register() becomes the only official way to register in the
table. Those protocols that were always static and unlikely anybody
is interested in making them loadable, are now registered by ip_init(),
ip6_init(). An IP protocol that considers itself unloadable shall
register itself within its own private SYSINIT().

Reviewed by: tuexen, melifaro
Differential revision: https://reviews.freebsd.org/D36157

raw ip6: merge rip6_output() into rip6_send()

While here remove some code that was compat legacy back in 2005, added
in a1f7e5f8ee7fe.

Reviewed by: melifaro
Differential revision: https://reviews.freebsd.org/D36128

protocols: init with standard SYSINIT(9) or VNET_SYSINIT

The historical BSD network stack loop that rolls over domains and
over protocols has no advantages over more modern SYSINIT(9).
While doing the sweep, split global and per-VNET initializers.

Getting rid of pr_init allows to achieve several things:
o Get rid of ifdef's that protect against double foo_init() when
both INET and INET6 are compiled in.
o Isolate initializers statically to the module they init.
o Makes code easier to understand and maintain.

Reviewed by: melifaro
Differential revision: https://reviews.freebsd.org/D33537

Convert route caching to nexthop caching.

This change is build on top of nexthop objects introduced in r359823.

Nexthops are separate datastructures, containing all necessary information
to perform packet forwarding such as gateway interface and mtu. Nexthops
are shared among the routes, providing more pre-computed cache-efficient
data while requiring less memory. Splitting the LPM code and the attached
data solves multiple long-standing problems in the routing layer,
drastically reduces the coupling with outher parts of the stack and allows
to transparently introduce faster lookup algorithms.

Route caching was (re)introduced to minimise (slow) routing lookups, allowing
for notably better performance for large TCP senders. Caching works by
acquiring rtentry reference, which is protected by per-rtentry mutex.
If the routing table is changed (checked by comparing the rtable generation id)
or link goes down, cache record gets withdrawn.

Nexthops have the same reference counting interface, backed by refcount(9).
This change merely replaces rtentry with the actual forwarding nextop as a
cached object, which is mostly mechanical. Other moving parts like cache
cleanup on rtable change remains the same.

Differential Revision: https://reviews.freebsd.org/D24340

ip6: retire in6_selectroute_fib() as promised 8 years ago

In r231852 I added in6_selectroute_fib() as a compat function with the
fibnum as an extra argument compared to in6_selectroute() to keep the
KPI stable.
Way too late retire this function again and add the fib to in6_selectroute()
which also only has a single consumer now and was an orphan function before.

frag6: replace KAME hand-rolled queues with queue(9) TAILQs

Remove the KAME custom circular queue for fragments and fragmented packets
and replace them with a standard TAILQ.
This make the code a lot more understandable and maintainable and removes
further hand-rolled code from the the tree using a standard interface instead.

Hide the still public structures under #ifdef _KERNEL as there is no
use for them in user space.
The naming is a bit confusing now as struct ip6q and the ip6q[] buckets
array are not the same anymore; sadly struct ip6q is also used by the
MAC framework and we cannot rename it.

Submitted by: jtl (initally)
MFC after: 3 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D16847 (jtl's original)

frag6: fix vnet teardown leak

When shutting down a VNET we did not cleanup the fragmentation hashes.
This has multiple problems: (1) leak memory but also (2) leak on the
global counters, which might eventually lead to a problem on a system
starting and stopping a lot of vnets and dealing with a lot of IPv6
fragments that the counters/limits would be exhausted and processing
would no longer take place.

Unfortunately we do not have a useable variable to indicate when
per-VNET initialization of frag6 has happened (or when destroy happened)
so introduce a boolean to flag this. This is needed here as well as
it was in r353635 for ip_reass.c in order to avoid tripping over the
already destroyed locks if interfaces go away after the frag6 destroy.

While splitting things up convert the TRY_LOCK to a LOCK operation in
now frag6_drain_one(). The try-lock was derived from a manual hand-rolled
implementation and carried forward all the time. We no longer can afford
not to get the lock as that would mean we would continue to leak memory.

Assert that all the buckets are empty before destroying to lock to
ensure long-term stability of a clean shutdown.

Reported by: hselasky
Reviewed by: hselasky
MFC after: 3 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D22054

frag6: move public structure into file local space.

Move ip6asfrag and the accompanying IP6_REASS_MBUF macro from
ip6_var.h into frag6.c as they are not used outside frag6.c.
Sadly struct ip6q is all over the mac framework so we have to
leave it public.

This reduces the public KPI space.

MFC after: 3 months
X-MFC: possibly MFC the #define only to stable branches
Sponsored by: Netflix

frag6.c: move variables and sysctls into local file

Move the sysctls and the related variables only used in frag6.c
into the file and out of in6_proto.c. That way everything belonging
together is in one place.

Sort the variables into global and per-vnet scopes and make
them static. No longer export the (helper) function
frag6_set_bucketsize() now also file-local only.

Should be no functional changes, only reduced public KPI/KBI surface.

MFC after: 3 months
Sponsored by: Netflix

Convert all IPv4 and IPv6 multicast memberships into using a STAILQ
instead of a linear array.

The multicast memberships for the inpcb structure are protected by a
non-sleepable lock, INP_WLOCK(), which needs to be dropped when
calling the underlying possibly sleeping if_ioctl() method. When using
a linear array to keep track of multicast memberships, the computed
memory location of the multicast filter may suddenly change, due to
concurrent insertion or removal of elements in the linear array. This
in turn leads to various invalid memory access issues and kernel
panics.

To avoid this problem, put all multicast memberships on a STAILQ based
list. Then the memory location of the IPv4 and IPv6 multicast filters
become fixed during their lifetime and use after free and memory leak
issues are easier to track, for example by: vmstat -m | grep multi

All list manipulation has been factored into inline functions
including some macros, to easily allow for a future hash-list
implementation, if needed.

This patch has been tested by pho@ .

Differential Revision: https://reviews.freebsd.org/D20080
Reviewed by: markj @
MFC after: 1 week
Sponsored by: Mellanox Technologies

Add stat counter for ipv6 atomic fragments

Add a stat counter to track ipv6 atomic fragments. Atomic fragments can be
generated in response to invalid path MTU values, but are also a potential
attack vector and considered harmful (see RFC6946 and RFC8021).

While here add tracking of the atomic fragment counter to netstat and systat.

Reviewed by: tuexen, jtl, bz
Approved by: jtl (mentor), bz (mentor)
Event: Aberdeen hackathon 2019
Differential Revision: https://reviews.freebsd.org/D17511

Update for IETF draft-ietf-6man-ipv6only-flag.

All changes are hidden behind the EXPERIMENTAL option and are not compiled
in by default.

Add ND6_IFF_IPV6_ONLY_MANUAL to be able to set the interface into no-IPv4-mode
manually without router advertisement options. This will allow developers to
test software for the appropriate behaviour even on dual-stack networks or
IPv6-Only networks without the option being set in RA messages.
Update ifconfig to allow setting and displaying the flag.

Update the checks for the filters to check for either the automatic or the manual
flag to be set. Add REVARP to the list of filtered IPv4-related protocols and add
an input filter similar to the output filter.

Add a check, when receiving the IPv6-Only RA flag to see if the receiving
interface has any IPv4 configured. If it does, ignore the IPv6-Only flag.

Add a per-VNET global sysctl, which is on by default, to not process the automatic
RA IPv6-Only flag. This way an administrator (if this is compiled in) has control
over the behaviour in case the node still relies on IPv4.

New pfil(9) KPI together with newborn pfil API and control utility.

The KPI have been reviewed and cleansed of features that were planned
back 20 years ago and never implemented. The pfil(9) internals have
been made opaque to protocols with only returned types and function
declarations exposed. The KPI is made more strict, but at the same time
more extensible, as kernel uses same command structures that userland
ioctl uses.

In nutshell [KA]PI is about declaring filtering points, declaring
filters and linking and unlinking them together.

New [KA]PI makes it possible to reconfigure pfil(9) configuration:
change order of hooks, rehook filter from one filtering point to a
different one, disconnect a hook on output leaving it on input only,
prepend/append a filter to existing list of filters.

Now it possible for a single packet filter to provide multiple rulesets
that may be linked to different points. Think of per-interface ACLs in
Cisco or Juniper. None of existing packet filters yet support that,
however limited usage is already possible, e.g. default ruleset can
be moved to single interface, as soon as interface would pride their
filtering points.

Another future feature is possiblity to create pfil heads, that provide
not an mbuf pointer but just a memory pointer with length. That would
allow filtering at very early stages of a packet lifecycle, e.g. when
packet has just been received by a NIC and no mbuf was yet allocated.

Differential Revision: https://reviews.freebsd.org/D18951

Implement a limit on on the number of IPv6 reassembly queues per bucket.

There is a hashing algorithm which should distribute IPv6 reassembly
queues across the available buckets in a relatively even way. However,
if there is a flaw in the hashing algorithm which allows a large number
of IPv6 fragment reassembly queues to end up in a single bucket, a per-
bucket limit could help mitigate the performance impact of this flaw.

Implement such a limit, with a default of twice the maximum number of
reassembly queues divided by the number of buckets. Recalculate the
limit any time the maximum number of reassembly queues changes.
However, allow the user to override the value using a sysctl
(net.inet6.ip6.maxfragbucketsize).

Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923

Add a limit of the number of fragments per IPv6 packet.

The IPv4 fragment reassembly code supports a limit on the number of
fragments per packet. The default limit is currently 17 fragments.
Among other things, this limit serves to limit the number of fragments
the code must parse when trying to reassembly a packet.

Add a limit to the IPv6 reassembly code. By default, limit a packet
to 65 fragments (64 on the queue, plus one final fragment to complete
the packet). This allows an average fragment size of 1,008 bytes, which
should be sufficient to hold a fragment. (Recall that the IPv6 minimum
MTU is 1280 bytes. Therefore, this configuration allows a full-size
IPv6 packet to be fragmented on a link with the minimum MTU and still
carry approximately 272 bytes of headers before the fragmented portion
of the packet.)

Users can adjust this limit using the net.inet6.ip6.maxfragsperpacket
sysctl.

Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923

Make the IPv6 fragment limits be global, rather than per-VNET, limits.

The IPv6 reassembly fragment limit is based on the number of mbuf clusters,
which are a global resource. However, the limit is currently applied
on a per-VNET basis. Given enough VNETs (or given sufficient customization
on enough VNETs), it is possible that the sum of all the VNET fragment
limits will exceed the number of mbuf clusters available in the system.

Given the fact that the fragment limits are intended (at least in part) to
regulate access to a global resource, the IPv6 fragment limit should
be applied on a global basis.

Note that it is still possible to disable fragmentation for a particular
VNET by setting the net.inet6.ip6.maxfragpackets sysctl to 0 for that
VNET. In addition, it is now possible to disable fragmentation globally
by setting the net.inet6.ip6.maxfrags sysctl to 0.

Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923

ip(6)_freemoptions: defer imo destruction to epoch callback task

Avoid the ugly unlock / lock of the inpcbinfo where we need to
figure out what kind of lock we hold by simply deferring the
operation to another context. (Also a small dependency for
converting the pcbinfo read lock to epoch)

Modify ip6_get_prevhdr() to be able use it safely.

Instead of returning pointer to the previous header, return its offset.
In frag6_input() use m_copyback() and determined offset to store next
header instead of accessing to it by pointer and assuming that the memory
is contiguous.

In rip6_input() use offset returned by ip6_get_prevhdr() instead of
calculating it from pointers arithmetic, because IP header can belong
to another mbuf in the chain.

Reported by: Maxime Villard <max at m00nbsd dot net>
Reviewed by: kp
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D14158

sys: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

The pr_destroy field does not allow us to run the teardown code in a
specific order. VNET_SYSUNINITs however are doing exactly that.
Thus remove the VIMAGE conditional field from the domain(9) protosw
structure and replace it with VNET_SYSUNINITs.
This also allows us to change some order and to make the teardown functions
file local static.
Also convert divert(4) as it uses the same mechanism ip(4) and ip6(4) use
internally.

Slightly reshuffle the SI_SUB_* fields in kernel.h and add a new ones, e.g.,
for pfil consumers (firewalls), partially for this commit and for others
to come.

Reviewed by: gnn, tuexen (sctp), jhb (kernel.h)
Obtained from: projects/vnet
MFC after: 2 weeks
X-MFC: do not remove pr_destroy
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D6652

New way to manage reference counting of mbuf external storage.

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

MFp4 @180892:

With pr_destroy being gone, call ip6_destroy from an ordered
NET_SYSUNINT. Make ip6_destroy() static as well.

Sponsored by: The FreeBSD Foundation

Split in6_selectsrc() into in6_selectsrc_addr() and in6_selectsrc_socket().

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)

Remove 'struct route_int6' argument from in6_selectsrc() and
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.

[netinet6]: Create a new IPv6 netisr which expects the frames to have been verified.

This is required for fragments and encapsulated data (eg tunneling) to be redistributed
to the RSS bucket based on the eventual IPv6 header and protocol (TCP, UDP, etc) header.

* Add an mbuf tag with the state of IPv6 options parsing before the frame is queued
into the direct dispatch handler;
* Continue processing and complete the frame reception in the correct RSS bucket /
netisr context.

Testing results are in the phabricator review.

Differential Revision: https://reviews.freebsd.org/D3563
Submitted by: Tiwei Bie <btw@mail.ustc.edu.cn>

Implement RSS hashing/re-hashing for IPv6 ingress packets.

This mirrors the basic IPv4 implementation - IPv6 packets under RSS
now are checked for a correct RSS hash and if one isn't provided,
it's done in software.

This only handles the initial receive - it doesn't yet handle
reinjecting / rehashing packets after being decapsulated from
various tunneling setups. That'll come in some follow-up work.

For non-RSS users, this is almost a giant no-op.

It does change a couple of ipv6 methods to use const mbuf * instead of
mbuf * but it doesn't have any functional changes.

So, the following now occurs:

* If the NIC doesn't do any RSS hashing, it's all done in software.
Single-queue, non-RSS NICs will now have the RX path distributed
into multiple receive netisr queues.

* If the NIC provides the wrong hash (eg only IPv6 hash when we needed
an IPv6 TCP hash, or IPv6 UDP hash when we expected IPv6 hash)
then the hash is recalculated.

* .. if the hash is recalculated, it'll end up being injected into
the correct netisr queue for v6 processing.

Submitted by: Tiwei Bie <btw@mail.ustc.edu.cn>
Differential Revision: https://reviews.freebsd.org/D3504

Simplify ip[6] simploop:
Do not pass 'dst' sockaddr to ip[6]_mloopback:
- We have explicit check for AF_INET in ip_output()
- We assume ip header inside passed mbuf in ip_mloopback
- We assume ip6 header inside passed mbuf in ip6_mloopback

Preserve IPv6 fragment IDs accross reassembly and refragmentation

When forwarding fragmented IPv6 packets and filtering with PF we
reassemble and refragment. That means we generate new fragment headers
and a new fragment ID.

We already save the fragment IDs so we can do the reassembly so it's
straightforward to apply the incoming fragment ID on the refragmented
packets.

Differential Revision: https://reviews.freebsd.org/D2188
Approved by: gnn (mentor)

Fix deadlock in IPv6 PCB code.

When several threads are trying to send datagram to the same destination,
but fragmentation is disabled and datagram size exceeds link MTU,
ip6_output() calls pfctlinput2(PRC_MSGSIZE). It does notify all
sockets wanted to know MTU to this destination. And since all threads
hold PCB lock while sending, taking the lock for each PCB in the
in6_pcbnotify() leads to deadlock.

RFC 3542 p.11.3 suggests notify all application wanted to receive
IPV6_PATHMTU ancillary data for each ICMPv6 packet too big message.
But it doesn't require this, when we don't receive ICMPv6 message.

Change ip6_notify_pmtu() function to be able use it directly from
ip6_output() to notify only one socket, and to notify all sockets
when ICMPv6 packet too big message received.

PR: 197059
Differential Revision: https://reviews.freebsd.org/D1949
Reviewed by: no objection from #network
Obtained from: Yandex LLC
MFC after: 1 week
Sponsored by: Yandex LLC

Factor out ip6_fragment() function, to be used in IPv6 stack and pf(4).

Submitted by: Kristof Provost
Differential Revision: D1766

Factor out ip6_deletefraghdr() function, to be shared between IPv6
stack and pf(4).

Submitted by: Kristof Provost
Reviewed by: ae
Differential Revision: D1764

Renove faith(4) and faithd(8) from base. It looks like industry
have chosen different (and more traditional) stateless/statuful
NAT64 as translation mechanism. Last non-trivial commits to both
faith(4) and faithd(8) happened more than 12 years ago, so I assume
it is time to drop RFC3142 in FreeBSD.

No objections from: net@

Remove ip6_getdstifaddr() and all functions to work with auxiliary data.
It isn't safe to keep unreferenced ifaddrs. Use in6ifa_ifwithaddr() to
determine ifaddr corresponding to destination address. Since currently
we keep addresses with embedded scope zone, in6ifa_ifwithaddr is called
with zero zoneid and marked with XXX.

Also remove route and lle lookups from ip6_input. Use in6ifa_ifwithaddr()
instead.

Sponsored by: Yandex LLC

Convert netinet6/ to use new routing API.

* Remove &ifpp from ip6_output() in favor of ri->ri_nh_info
* Provide different wrappers to in6_selectsrc:
Currently it is used by 2 differenct type of customers:
- socket-based one, which all are unsure about provided
address scope and
- in-kernel ones (ND code mostly), which don't have
any sockets, options, crededentials, etc.
So, we provide two different wrappers to in6_selectsrc()
returning select source.
* Make different versions of selectroute():
Currenly selectroute() is used in two scenarios:
- SAS, via in6_selecsrc() -> in6_selectif() -> selectroute()
- output, via in6_output -> wrapper -> selectroute()
Provide different versions for each customer:
- fib6_lookup_nh_basic()-based in6_selectif() which is
capable of returning interface only, without MTU/NHOP/L2
calculations
- full-blown fib6_selectroute() with cached route/multipath/
MTU/L2
* Stop using routing table for link-local address lookups
* Add in6_ifawithifp_lla() to make for-us check faster for link-local
* Add in6_splitscope / in6_setllascope for faster embed/deembed scopes

Merge 'struct ip6protosw' and 'struct protosw' into one. Now we have
only one protocol switch structure that is shared between ipv4 and ipv6.

Phabric: D476
Reviewed by: jhb

Fixed IPv4-in-IPv6 and IPv6-in-IPv4 IPsec tunnels.
For IPv6-in-IPv4, you may need to do the following command
on the tunnel interface if it is configured as IPv4 only:
ifconfig <interface> inet6 -ifdisabled

Code logic inspired from NetBSD.

PR: kern/169438
Submitted by: emeric.poupon@netasq.com
Reviewed by: fabient, ae
Obtained from: NETASQ

Since both netinet/ and netinet6/ call into netipsec/ and netpfil/,
the protocol specific mbuf flags are shared between them.

- Move all M_FOO definitions into a single place: netinet/in6.h, to
avoid future clashes.
- Resolve clash between M_DECRYPTED and M_SKIP_FIREWALL which resulted
in a failure of operation of IPSEC and packet filters.

Thanks to Nicolas and Georgios for all the hard work on bisecting,
testing and finally finding the root of the problem.

PR: kern/186755
PR: kern/185876
In collaboration with: Georgios Amanakis <gamanakis gmail.com>
In collaboration with: Nicolas DEFFAYET <nicolas-ml deffayet.com>
Sponsored by: Nginx, Inc.

Move the global M_SKIP_FIREWALL mbuf flags to a protocol layer specific
flag instead. The flag is only used within the IP and IPv6 layer 3
protocols.

Because some firewall packages treat IPv4 and IPv6 packets the same the
flag should have the same value for both.

Discussed with: trociny, glebius

Migrate structs ip6stat, icmp6stat and rip6stat to PCPU counters.

Prepare network statistics structures for migration to PCPU counters.
Use uint64_t as type for all fields of structures.

Changed structures: ahstat, arpstat, espstat, icmp6_ifstat, icmp6stat,
in6_ifstat, ip6stat, ipcompstat, ipipstat, ipsecstat, mrt6stat, mrtstat,
pfkeystat, pim6stat, pimstat, rip6stat, udpstat.

Discussed with: arch@

Fix build after r249543.

Replace hardcoded numbers.

Use M_PROTO7 flag for M_IP6_NEXTHOP, because M_PROTO2 was used for
M_AUTHIPHDR.

Pointy hat to: ae
Reported by: Vadim Goncharov
MFC after: 3 days

Remove the recently added sysctl variable net.pfil.forward.
Instead, add protocol specific mbuf flags M_IP_NEXTHOP and
M_IP6_NEXTHOP. Use them to indicate that the mbuf's chain
contains the PACKET_TAG_IPFORWARD tag. And do a tag lookup
only when this flag is set.

Suggested by: andre

Remove __P.

Submitted by: kevlo
Reviewed by: md5(1)
MFC after: 2 months

MFp4 bz_ipv6_fast:

Hide the ip6aux functions. The only one referenced outside ip6_input.c
is not compiled in yet (__notyet__) in route6.c (r235954). We do have
accessor functions that should be used.

Sponsored by: The FreeBSD Foundation
Sponsored by: iXsystems

Reviewed by: gnn (as part of the whole)
MFC After: 3 days
X-MFC: KPI?

In selectroute() add a missing fibnum argument to an in6_rtalloc()
call in an #if 0 section.

In in6_selecthlim() optimize a case where in6p cannot be NULL due to an
earlier check.

More consistently use u_int instead of int for fibnum function arguments.

Sponsored by: Cisco Systems, Inc.
MFC after: 3 days

Add multi-FIB IPv6 support to the core network stack supplementing
the original IPv4 implementation from r178888:

- Use RT_DEFAULT_FIB in the IPv4 implementation where noticed.
- Use rt*fib() KPI with explicit RT_DEFAULT_FIB where applicable in
the NFS code.
- Use the new in6_rt* KPI in TCP, gif(4), and the IPv6 network stack
where applicable.
- Split in6_rtqtimo() and in6_mtutimo() as done in IPv4 and equally
prevent multiple initializations of callouts in in6_inithead().
- Use wrapper functions where needed to preserve the current KPI to
ease MFCs. Use BURN_BRIDGES to indicate expected future cleanup.
- Fix (related) comments (both technical or style).
- Convert to rtinit() where applicable and only use custom loops where
currently not possible otherwise.
- Multicast group, most neighbor discovery address actions and faith(4)
are locked to the default FIB. Individual IPv6 addresses will only
appear in the default FIB, however redirect information and prefixes
of connected subnets are automatically propagated to all FIBs by
default (mimicking IPv4 behavior as closely as possible).

Sponsored by: Cisco Systems, Inc.

Add $ipv6_cpe_wanif to enable functionality required for IPv6 CPE
(r225485). When setting an interface name to it, the following
configurations will be enabled:

1. "no_radr" is set to all IPv6 interfaces automatically.

2. "-no_radr accept_rtadv" will be set only for $ipv6_cpe_wanif. This is
done just before evaluating $ifconfig_IF_ipv6 in the rc.d scripts (this
means you can manually supersede this configuration if necessary).

3. The node will add RA-sending routers to the default router list
even if net.inet6.ip6.forwarding=1.

This mode is added to conform to RFC 6204 (a router which connects
the end-user network to a service provider network). To enable
packet forwarding, you still need to set ipv6_gateway_enable=YES.

Note that accepting router entries into the default router list when
packet forwarding capability and a routing daemon are enabled can
result in messing up the routing table. To minimize such unexpected
behaviors, "no_radr" is set on all interfaces but $ipv6_cpe_wanif.

Approved by: re (bz)

- Accept Router Advertisement messages even when net.inet6.ip6.forwarding=1.

- A new per-interface knob IFF_ND6_NO_RADR and sysctl IPV6CTL_NO_RADR.
This controls if accepting a route in an RA message as the default route.
The default value for each interface can be set by net.inet6.ip6.no_radr.
The system wide default value is 0.

- A new sysctl: net.inet6.ip6.norbit_raif. This controls if setting R-bit in
NA on RA accepting interfaces. The default is 0 (R-bit is set based on
net.inet6.ip6.forwarding).

Background:

IPv6 host/router model suggests a router sends an RA and a host accepts it for
router discovery. Because of that, KAME implementation does not allow
accepting RAs when net.inet6.ip6.forwarding=1. Accepting RAs on a router can
make the routing table confused since it can change the default router
unintentionally.

However, in practice there are cases where we cannot distinguish a host from
a router clearly. For example, a customer edge router often works as a host
against the ISP, and as a router against the LAN at the same time. Another
example is a complex network configurations like an L2TP tunnel for IPv6
connection to Internet over an Ethernet link with another native IPv6 subnet.
In this case, the physical interface for the native IPv6 subnet works as a
host, and the pseudo-interface for L2TP works as the default IP forwarding
route.

Problem:

Disabling processing RA messages when net.inet6.ip6.forwarding=1 and
accepting them when net.inet6.ip6.forward=0 cause the following practical
issues:

- A router cannot perform SLAAC. It becomes a problem if a box has
multiple interfaces and you want to use SLAAC on some of them, for
example. A customer edge router for IPv6 Internet access service
using an IPv6-over-IPv6 tunnel sometimes needs SLAAC on the
physical interface for administration purpose; updating firmware
and so on (link-local addresses can be used there, but GUAs by
SLAAC are often used for scalability).

- When a host has multiple IPv6 interfaces and it receives multiple RAs on
them, controlling the default route is difficult. Router preferences
defined in RFC 4191 works only when the routers on the links are
under your control.

Details of Implementation Changes:

Router Advertisement messages will be accepted even when
net.inet6.ip6.forwarding=1. More precisely, the conditions are as
follow:

(ACCEPT_RTADV && !NO_RADR && !ip6.forwarding)
=> Normal RA processing on that interface. (as IPv6 host)

(ACCEPT_RTADV && (NO_RADR || ip6.forwarding))
=> Accept RA but add the router to the defroute list with
rtlifetime=0 unconditionally. This effectively prevents
from setting the received router address as the box's
default route.

(!ACCEPT_RTADV)
=> No RA processing on that interface.

ACCEPT_RTADV and NO_RADR are per-interface knob. In short, all interface
are classified as "RA-accepting" or not. An RA-accepting interface always
processes RA messages regardless of ip6.forwarding. The difference caused by
NO_RADR or ip6.forwarding is whether the RA source address is considered as
the default router or not.

R-bit in NA on the RA accepting interfaces is set based on
net.inet6.ip6.forwarding. While RFC 6204 W-1 rule (for CPE case) suggests
a router should disable the R-bit completely even when the box has
net.inet6.ip6.forwarding=1, I believe there is no technical reason with
doing so. This behavior can be set by a new sysctl net.inet6.ip6.norbit_raif
(the default is 0).

Usage:

# ifconfig fxp0 inet6 accept_rtadv
=> accept RA on fxp0
# ifconfig fxp0 inet6 accept_rtadv no_radr
=> accept RA on fxp0 but ignore default route information in it.
# sysctl net.inet6.ip6.norbit_no_radr=1
=> R-bit in NAs on RA accepting interfaces will always be set to 0.

Fix more continuous/contiguous typos (cf. r215955)

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

MFp4 CH=183052 183053 183258:

In protosw we define pr_protocol as short, while on the wire
it is an uint8_t. That way we can have "internal" protocols
like DIVERT, SEND or gaps for modules (PROTO_SPACER).
Switch ipproto_{un,}register to accept a short protocol number(*)
and do an upfront check for valid boundries. With this we
also consistently report EPROTONOSUPPORT for out of bounds
protocols, as we did for proto == 0. This allows a caller
to not error for this case, which is especially important
if we want to automatically call these from domain handling.

(*) the functions have been without any in-tree consumer
since the initial introducation, so this is considered save.

Implement ip6proto_{un,}register() similarly to their legacy IP
counter parts to allow modules to hook up dynamically.

Reviewed by: philip, will
MFC after: 1 week

MFC r207369:
MFP4: @176978-176982, 176984, 176990-176994, 177441

"Whitspace" churn after the VIMAGE/VNET whirls.

Remove the need for some "init" functions within the network
stack, like pim6_init(), icmp_init() or significantly shorten
others like ip6_init() and nd6_init(), using static initialization
again where possible and formerly missed.

Move (most) variables back to the place they used to be before the
container structs and VIMAGE_GLOABLS (before r185088) and try to
reduce the diff to stable/7 and earlier as good as possible,
to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9.

This also removes some header file pollution for putatively
static global variables.

Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are
no longer needed.

Reviewed by: jhb
Discussed with: rwatson
Sponsored by: The FreeBSD Foundation
Sponsored by: CK Software GmbH

MFP4: @176978-176982, 176984, 176990-176994, 177441

"Whitspace" churn after the VIMAGE/VNET whirls.

Remove the need for some "init" functions within the network
stack, like pim6_init(), icmp_init() or significantly shorten
others like ip6_init() and nd6_init(), using static initialization
again where possible and formerly missed.

Move (most) variables back to the place they used to be before the
container structs and VIMAGE_GLOABLS (before r185088) and try to
reduce the diff to stable/7 and earlier as good as possible,
to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9.

This also removes some header file pollution for putatively
static global variables.

Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are
no longer needed.

Reviewed by: jhb
Discussed with: rwatson
Sponsored by: The FreeBSD Foundation
Sponsored by: CK Software GmbH
MFC after: 6 days

MFC of 197952 and 198075

Virtualize the pfil hooks so that different jails may chose different
packet filters. ALso allows ipfw to be enabled on on ejail and disabled
on another. In 8.0 it's a global setting.
and
Unbreak the VIMAGE build with IPSEC, broken with r197952 by
virtualizing the pfil hooks.
For consistency add the V_ to virtualize the pfil hooks in here as well.

Virtualize the pfil hooks so that different jails may chose different
packet filters. ALso allows ipfw to be enabled on on ejail and disabled
on another. In 8.0 it's a global setting.

Sitting aroung in tree waiting to commit for: 2 months
MFC after: 2 months

Remove unused VNET_SET() and related macros; only VNET_GET() is
ever actually used. Rename VNET_GET() to VNET() to shorten
variable references.

Discussed with: bz, julian
Reviewed by: bz
Approved by: re (kensmith, kib)

Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator. Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...). This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack. Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory. Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy. Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address. When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by: bz
Reviewed by: bz, zec
Discussed with: gnn, jamie, jeff, jhb, julian, sam
Suggested by: peter
Approved by: re (kensmith)

Make callers to in6_selectsrc() and in6_pcbladdr() pass in memory
to save the selected source address rather than returning an
unreferenced copy to a pointer that might long be gone by the
time we use the pointer for anything meaningful.

Asked for by: rwatson
Reviewed by: rwatson

Introduce an infrastructure for dismantling vnet instances.

Vnet modules and protocol domains may now register destructor
functions to clean up and release per-module state. The destructor
mechanisms can be triggered by invoking "vimage -d", or a future
equivalent command which will be provided via the new jail framework.

While this patch introduces numerous placeholder destructor functions,
many of those are currently incomplete, thus leaking memory or (even
worse) failing to stop all running timers. Many of such issues are
already known and will be incrementaly fixed over the next weeks in
smaller incremental commits.

Apart from introducing new fields in structs ifnet, domain, protosw
and vnet_net, which requires the kernel and modules to be rebuilt, this
change should have no impact on nooptions VIMAGE builds, since vnet
destructors can only be called in VIMAGE kernels. Moreover,
destructor functions should be in general compiled in only in
options VIMAGE builds, except for kernel modules which can be safely
kldunloaded at run time.

Bump __FreeBSD_version to 800097.
Reviewed by: bz, julian
Approved by: rwatson, kib (re), julian (mentor)

Bite the bullet, and make the IPv6 SSM and MLDv2 mega-commit:
import from p4 bms_netdev. Summary of changes:

* Connect netinet6/in6_mcast.c to build.
The legacy KAME KPIs are mostly preserved.
* Eliminate now dead code from ip6_output.c.
Don't do mbuf bingo, we are not going to do RFC 2292 style
CMSG tricks for multicast options as they are not required
by any current IPv6 normative reference.
* Refactor transports (UDP, raw_ip6) to do own mcast filtering.
SCTP, TCP unaffected by this change.
* Add ip6_msource, in6_msource structs to in6_var.h.
* Hookup mld_ifinfo state to in6_ifextra, allocate from
domifattach path.
* Eliminate IN6_LOOKUP_MULTI(), it is no longer referenced.
Kernel consumers which need this should use in6m_lookup().
* Refactor IPv6 socket group memberships to use a vector (like IPv4).
* Update ifmcstat(8) for IPv6 SSM.
* Add witness lock order for IN6_MULTI_LOCK.
* Move IN6_MULTI_LOCK out of lower ip6_output()/ip6_input() paths.
* Introduce IP6STAT_ADD/SUB/INC/DEC as per rwatson's IPv4 cleanup.
* Update carp(4) for new IPv6 SSM KPIs.
* Virtualize ip6_mrouter socket.
Changes mostly localized to IPv6 MROUTING.
* Don't do a local group lookup in MROUTING.
* Kill unused KAME prototypes in6_purgemkludge(), in6_restoremkludge().
* Preserve KAME DAD timer jitter behaviour in MLDv1 compatibility mode.
* Bump __FreeBSD_version to 800084.
* Update UPDATING.

NOTE WELL:
* This code hasn't been tested against real MLDv2 queriers
(yet), although the on-wire protocol has been verified in Wireshark.
* There are a few unresolved issues in the socket layer APIs to
do with scope ID propagation.
* There is a LOR present in ip6_output()'s use of
in6_setscope() which needs to be resolved. See comments in mld6.c.
This is believed to be benign and can't be avoided for the moment
without re-introducing an indirect netisr.

This work was mostly derived from the IGMPv3 implementation, and
has been sponsored by a third party.

Remove the single global unlocked route cache ip6_forward_rt
from the inet6 stack along with statistics and make sure we
properly free the rt in all cases.

While the current situation is not better performance wise it
prevents panics seen more often these days.
After more inet6 and ipsec cleanup we should be able to improve
the situation again passing the rt to ip6_forward directly.

Leave the ip6_forward_rt entry in struct vinet6 but mark it
for removal.

PR: kern/128247, kern/131038
MFC after: 25 days
Committed from: Bugathon #6
Tested by: Denis Ahrens <denis@h3q.com> (different initial version)

Remove 4 entirely unsued ip6 variables.
Leave then in struct vinet6 to not break the ABI with kernel modules
but mark them for removal so we can do it in one batch when the time
is right.

MFC after: 1 month

This main goals of this project are:
1. separating L2 tables (ARP, NDP) from the L3 routing tables
2. removing as much locking dependencies among these layers as
possible to allow for some parallelism in the search operations
3. simplify the logic in the routing code,

The most notable end result is the obsolescent of the route
cloning (RTF_CLONING) concept, which translated into code reduction
in both IPv4 ARP and IPv6 NDP related modules, and size reduction in
struct rtentry{}. The change in design obsoletes the semantics of
RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland
applications such as "arp" and "ndp" have been modified to reflect
those changes. The output from "netstat -r" shows only the routing
entries.

Quite a few developers have contributed to this project in the
past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and
Andre Oppermann. And most recently:

- Kip Macy revised the locking code completely, thus completing
the last piece of the puzzle, Kip has also been conducting
active functional testing
- Sam Leffler has helped me improving/refactoring the code, and
provided valuable reviews
- Julian Elischer setup the perforce tree for me and has helped
me maintaining that branch before the svn conversion

Second round of putting global variables, which were virtualized
but formerly missed under VIMAGE_GLOBAL.

Put the extern declarations of the virtualized globals
under VIMAGE_GLOBAL as the globals themsevles are already.
This will help by the time when we are going to remove the globals
entirely.

Sponsored by: The FreeBSD Foundation

Put a global variables, which were virtualized but formerly
missed under VIMAGE_GLOBAL.

Start putting the extern declarations of the virtualized globals
under VIMAGE_GLOBAL as the globals themsevles are already.
This will help by the time when we are going to remove the globals
entirely.

While there garbage collect a few dead externs from ip6_var.h.

Sponsored by: The FreeBSD Foundation

Add a MAC label, MAC Framework, and MAC policy entry points for IPv6
fragment reassembly queues.

This allows policies to label reassembly queues, perform access
control checks when matching fragments to a queue, update a queue
label when fragments are matched, and label the resulting
reassembled datagram.

Obtained from: TrustedBSD Project

- Import the HEAD csup code which is the basis for the cvsmode work.

Fix a regression introduced in r179289 splitting up ip6_savecontrol()
into v4-only vs. v6-only inp_flags processing.
When ip6_savecontrol_v4() is called from ip6_savecontrol() we
were not passing back the **mp thus the information will be missing
in userland.
Istead of going with a *** as suggested in the PR we are returning
**mp now and passing in the v4only flag as a pointer argument.

PR: kern/126349
Reviewed by: rwatson, dwmalone

Change the parameters to in6_selectsrc():
- pass in the inp instead of both in6p_moptions and laddr.
- pass in cred for upcoming prison checks.

Reviewed by: rwatson

Factor out the v4-only vs. the v6-only inp_flags processing in
ip6_savecontrol in preparation for udp_append() to no longer
need an WLOCK as we will no longer be modifying socket options.

Requested by: rwatson
Reviewed by: gnn
MFC after: 10 days

Replace the last susers calls in netinet6/ with privilege checks.

Introduce a new privilege allowing to set certain IP header options
(hop-by-hop, routing headers).

Leave a few comments to be addressed later.

Reviewed by: rwatson (older version, before addressing his comments)

Clean up VCS Ids.

Space cleanup

Approved by: re (rwatson)

cleanup about the reassembly structures and routine:
- removed unused structure members
- fixed a minor bug that the ECN code point may not be restored correctly

Approved by: ume (mentor)
MFC after: 1 week

Make IPv6 multicast forwarding dynamically loadable from a GENERIC kernel.
It is built in the same module as IPv4 multicast forwarding, i.e. ip_mroute.ko,
if and only if IPv6 support is enabled for loadable modules.
Export IPv6 forwarding structs to userland netstat(1) via sysctl(9).

sync with KAME (renamed a macro IPV6_DADOUTPUT to IPV6_UNSPECSRC)

Obtained from: KAME

added a knob to enable path MTU discovery for multicast packets.
(by default, it is disabled)

Submitted by: suz
Obtained from: KAME

supports stealth forwarding in IPv6, as well as in IPv4

PR: kern/54625
MFC after: 1 week

scope cleanup. with this change
- most of the kernel code will not care about the actual encoding of
scope zone IDs and won't touch "s6_addr16[1]" directly.
- similarly, most of the kernel code will not care about link-local
scoped addresses as a special case.
- scope boundary check will be stricter. For example, the current
*BSD code allows a packet with src=::1 and dst=(some global IPv6
address) to be sent outside of the node, if the application do:
s = socket(AF_INET6);
bind(s, "::1");
sendto(s, some_global_IPv6_addr);
This is clearly wrong, since ::1 is only meaningful within a single
node, but the current implementation of the *BSD kernel cannot
reject this attempt.

Submitted by: JINMEI Tatuya <jinmei__at__isl.rdc.toshiba.co.jp>
Obtained from: KAME

always copy ip6_pktopt. remove needcopy and needfree
argument/structure member accordingly.

Submitted by: Keiichi SHIMA <keiichi__at__iijlab.net>
Obtained from: KAME

be consistent on naming advanced API functions; use ip6_XXXpktopt(s).

Submitted by: Keiichi SHIMA <keiichi__at__iijlab.net>
Obtained from: KAME

Check the alignment of the IP header before passing the packet up to the
packet filter. This would cause a panic on architectures that require strict
alignment such as sparc64 (tier1) and ia64/ppc (tier2).

This adds two new macros that check the alignment, these are compile time
dependent on __NO_STRICT_ALIGNMENT which is set for i386 and amd64 where
alignment isn't need so the cost is avoided.

IP_HDR_ALIGNED_P()
IP6_HDR_ALIGNED_P()

Move bridge_ip_checkbasic()/bridge_ip6_checkbasic() up so that the alignment
is checked for ipfw and dummynet too.

PR: ia64/81284
Obtained from: NetBSD
Approved by: re (dwhite), mlaier (mentor)

/* -> /*- for license, minor formatting changes, separate for KAME

Always compile PFIL_HOOKS into the kernel and remove the associated kernel
compile option. All FreeBSD packet filters now use the PFIL_HOOKS API and
thus it becomes a standard part of the network stack.

If no hooks are connected the entire packet filter hooks section and related
activities are jumped over. This removes any performance impact if no hooks
are active.

Both OpenBSD and DragonFlyBSD have integrated PFIL_HOOKS permanently as well.

Get rid of the RANDOM_IP_ID option and make it a sysctl. NetBSD
have already done this, so I have styled the patch on their work:

1) introduce a ip_newid() static inline function that checks
the sysctl and then decides if it should return a sequential
or random IP ID.

2) named the sysctl net.inet.ip.random_id

3) IPv6 flow IDs and fragment IDs are now always random.
Flow IDs and frag IDs are significantly less common in the
IPv6 world (ie. rarely generated per-packet), so there should
be smaller performance concerns.

The sysctl defaults to 0 (sequential IP IDs).

Reviewed by: andre, silby, mlaier, ume
Based on: NetBSD
MFC after: 2 months

Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson

source address selection part of RFC3484.
TODO: since there is scope issue to be solved, multicast and
link-local address are treated as special for workaround for
now.

Obtained from: KAME

ip6_savecontrol() argument is redundant

hide m_tag, again.

Requested by: sam

cleanup use of m_tag.

Obtained from: KAME

re-add wrongly disappered IPV6_CHECKSUM stuff by introducing
ip6_raw_ctloutput().

Obtained from: KAME

Switch Advanced Sockets API for IPv6 from RFC2292 to RFC3542
(aka RFC2292bis). Though I believe this commit doesn't break
backward compatibility againt existing binaries, it breaks
backward compatibility of API.
Now, the applications which use Advanced Sockets API such as
telnet, ping6, mld6query and traceroute6 use RFC3542 API.

Obtained from: KAME

- implement lock around IPv6 reassembly, to avoid panic due to
frag6_drain (mutex version will come later).
- limit number of fragments (not fragment queues) in kernel.

Obtained from: KAME

- fix typo in comments.
- style.
- NULL is not 0.
- some variables were renamed.
- nuke unused logic.
(there is no functional change.)

Obtained from: KAME

randomize IPv6 flowlabel when RANDOM_IP_ID is defined.

Obtained from: KAME

we don't need ip6_id when RANDOM_IP_ID is defined.

Don't compiled ip6_randomid() in if RANDOM_IP_ID is not defined.

randomize IPv6 fragment ID.

Obtained from: KAME

o update PFIL_HOOKS support to current API used by netbsd
o revamp IPv4+IPv6+bridge usage to match API changes
o remove pfil_head instances from protosw entries (no longer used)
o add locking
o bump FreeBSD version for 3rd party modules

Heavy lifting by: "Max Laier" <max@love2party.net>
Supported by: FreeBSD Foundation
Obtained from: NetBSD (bits of pfil.h and pfil.c)

Update netisr handling; Each SWI now registers its queue, and all queue
drain routines are done by swi_net, which allows for better queue control
at some future point. Packets may also be directly dispatched to a netisr
instead of queued, this may be of interest at some installations, but
currently defaults to off.

Reviewed by: hsu, silby, jayanth, sam
Sponsored by: DARPA, NAI Labs

Fix typos, mostly s/ an / a / where appropriate and a few s/an/and/
Add FreeBSD Id tag where missing.

Replace aux mbufs with packet tags:

o instead of a list of mbufs use a list of m_tag structures a la openbsd
o for netgraph et. al. extend the stock openbsd m_tag to include a 32-bit
ABI/module number cookie
o for openbsd compatibility define a well-known cookie MTAG_ABI_COMPAT and
use this in defining openbsd-compatible m_tag_find and m_tag_get routines
o rewrite KAME use of aux mbufs in terms of packet tags
o eliminate the most heavily used aux mbufs by adding an additional struct
inpcb parameter to ip_output and ip6_output to allow the IPsec code to
locate the security policy to apply to outbound packets
o bump __FreeBSD_version so code can be conditionalized
o fixup ipfilter's call to ip_output based on __FreeBSD_version

Reviewed by: julian, luigi (silent), -arch, -net, darren
Approved by: julian, silence from everyone else
Obtained from: openbsd (mostly)
MFC after: 1 month

cleanup usage of ip6_mapped_addr_on and ip6_v6only. now,
ip6_mapped_addr_on is unified into ip6_v6only.

MFC after: 1 week

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha

Sync with recent KAME.
This work was based on kame-20010528-freebsd43-snap.tgz and some
critical problem after the snap was out were fixed.
There are many many changes since last KAME merge.

TODO:
- The definitions of SADB_* in sys/net/pfkeyv2.h are still different
from RFC2407/IANA assignment because of binary compatibility
issue. It should be fixed under 5-CURRENT.
- ip6po_m member of struct ip6_pktopts is no longer used. But, it
is still there because of binary compatibility issue. It should
be removed under 5-CURRENT.

Reviewed by: itojun
Obtained from: KAME
MFC after: 3 weeks

remove m_pulldown statistics, which is highly experimental and does not
belong to *bsd-merged tree

sync with kame tree as of july00. tons of bug fixes/improvements.

API changes:
- additional IPv6 ioctls
- IPsec PF_KEY API was changed, it is mandatory to upgrade setkey(8).
(also syntax change)

Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by: msmith and others

Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by: phk
Reviewed by: phk
Approved by: mdodd

IPSEC support in the kernel.
pr_input() routines prototype is also changed to support IPSEC and IPV6
chained protocol headers.

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project

KAME netinet6 basic part(no IPsec,no V6 Multicast Forwarding, no UDP/TCP
for IPv6 yet)

With this patch, you can assigne IPv6 addr automatically, and can reply to
IPv6 ping.

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project