MFC r331648:

Improve copy-and-pasted versions of SIOCGIFADDR.

The original implementation used a reference to ifr_data and a cast to
do the equivalent of accessing ifr_addr. This was copied multiple
times since 1996.

Approved by: kib
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14873

Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

This change re-adds L2 caching for TCP and UDP, as originally added in D4306
but removed due to other changes in the system. Restore the llentry pointer
to the "struct route", and use it to cache the L2 lookup (ARP or ND6) as
appropriate.

Submitted by: Mike Karels
Differential Revision: https://reviews.freebsd.org/D6262

sys/net*: minor spelling fixes.

No functional change.

sys: extend use of the howmany() macro when available.

We have a howmany() macro in the <sys/param.h> header that is
convenient to re-use as it makes things easier to read.

sys/net* : for pointers replace 0 with NULL.

Mostly cosmetical, no functional change.

Found with devel/coccinelle.

Finish r275196: do not dereference rtentry in if_output() routines.

The only piece of information that is required is rt_flags subset.

In particular, if_loop() requires RTF_REJECT and RTF_BLACKHOLE flags
to check if this particular mbuf needs to be dropped (and what
error should be returned).
Note that if_loop() will always return EHOSTUNREACH for "reject" routes
regardless of RTF_HOST flag existence. This is due to upcoming routing
changes where RTF_HOST value won't be available as lookup result.

All other functions require RTF_GATEWAY flag to check if they need
to return EHOSTUNREACH instead of EHOSTDOWN error.

There are 11 places where non-zero 'struct route' is passed to if_output().
For most of the callers (forwarding, bpf, arp) does not care about exact
error value. In fact, the only place where this result is propagated
is ip_output(). (ip6_output() passes NULL route to nd6_output_ifp()).

Given that, add 3 new 'struct route' flags (RT_REJECT, RT_BLACKHOLE and
RT_IS_GW) and inline function (rt_update_ro_flags()) to copy necessary
rte flags to ro_flags. Call this function in ip_output() after looking up/
verifying rte.

Reviewed by: ae

Replace the fastforward path with tryforward which does not require a
sysctl and will always be on. The former split between default and
fast forwarding is removed by this commit while preserving the ability
to use all network stack features.

Differential Revision: https://reviews.freebsd.org/D4042
Reviewed by: ae, melifaro, olivier, rwatson
MFC after: 1 month
Sponsored by: Rubicon Communications (Netgate)

Simplify the way of attaching IPv6 link-layer header.

Problem description:
How do we currently perform layer 2 resolution and header imposition:

For IPv4 we have the following chain:
ip_output() -> (ether|atm|whatever)_output() -> arpresolve()

Lookup is done in proper place (link-layer output routine) and it is possible
to provide cached lle data.

For IPv6 situation is more complex:
ip6_output() -> nd6_output() -> nd6_output_ifp() -> (whatever)_output() ->
nd6_storelladdr()

We have ip6_ouput() which calls nd6_output() instead of link output routine.
nd6_output() does the following:
* checks if lle exists, creates it if needed (similar to arpresolve())
* performes lle state transitions (similar to arpresolve())
* calls nd6_output_ifp() which pushes packets to link output routine along
with running SeND/MAC hooks regardless of lle state
(e.g. works as run-hooks placeholder).

After that, iface output routine like ether_output() calls nd6_storelladdr()
which performs lle lookup once again.

As a result, we perform lookup twice for each outgoing packet for most types
of interfaces. We also need to maintain runtime-checked table of 'nd6-free'
interfaces (see nd6_need_cache()).

Fix this behavior by eliminating first ND lookup. To be more specific:
* make all nd6_output() consumers use nd6_output_ifp() instead
* rename nd6_output[_slow]() to nd6_resolve_[slow]()
* convert nd6_resolve() and nd6_resolve_slow() to arpresolve() semantics,
e.g. copy L2 address to buffer instead of pushing packet towards lower
layers
* Make all nd6_storelladdr() users use nd6_resolve()
* eliminate nd6_storelladdr()

The resulting callchain is the following:
ip6_output() -> nd6_output_ifp() -> (whatever)_output() -> nd6_resolve()

Error handling:
Currently sending packet to non-existing la results in ip6_<output|forward>
-> nd6_output() -> nd6_output _lle() which returns 0.
In new scenario packet is propagated to <ether|whatever>_output() ->
nd6_resolve() which will return EWOULDBLOCK, and that result
will be converted to 0.

(And EWOULDBLOCK is actually used by IB/TOE code).

Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D1469

Fix typo.

Submitted by: Olivér Pintér

* Deal with ARCNET L2 multicast mapping for IPv6 the same way as in IPv4:
handle it in arc_output() instead of nd6_storelladdr().
* Remove IFT_ARCNET check from arpresolve() since arc_output() does not
use arpresolve() to handle broadcast/multicast. This check was there
since r84931. It looks like it was not used since r89099 (initial
import of Arcnet support where multicast is handled separately).
* Remove IFT_IEEE1394 case from nd6_storelladdr() since firewire_output()
calles nd6_storelladdr() for unicast addresses only.
* Remove IFT_ARCNET case from nd6_storelladdr() since arc_output() now
handles multicast by itself.

As a result, we have the following pattern: all non-ethernet-style
media have their own multicast map handling inside their appropriate
routines. On the other hand, arpresolve() (and nd6_storelladdr()) which
meant to be 'generic' ones de-facto handles ethernet-only multicast maps.

MFC after: 3 weeks

After r275196 unbreak NOIP and NOINET kernels by hiding an otherwise
unused varibale under the proper #ifdef.

Do not return unlocked/unreferenced lle in arpresolve/nd6_storelladdr -
return lle flags IFF needed.
Do not pass rte to arpresolve - pass is_gateway flag instead.

Mechanically convert to if_inc_counter().

Remove IPX support.

IPX was a network transport protocol in Novell's NetWare network operating
system from late 80s and then 90s. The NetWare itself switched to TCP/IP
as default transport in 1998. Later, in this century the Novell Open
Enterprise Server became successor of Novell NetWare. The last release
that claimed to still support IPX was OES 2 in 2007. Routing equipment
vendors (e.g. Cisco) discontinued support for IPX in 2011.

Thus, IPX won't be supported in FreeBSD 11.0-RELEASE.

Simplify filling sockaddr_dl structure for if_resolvemulti()
callback providers. link_init_sdl() function can be used to
fill most of the parameters. Use caller stack instead of
allocation / freing memory for each request. Do not drop support
for extra-long (probably non-existing) link-layer protocols by
introducing link_alloc_sdl() (used by if_resolvemulti() callback)
and link_free_sdl() (used by caller).
Since this change breaks KBI, MFC requires slightly different approach
(link_init_sdl() auto-allocating buffer if necessary to handle cases
with unmodified if_resolvemulti() callers).

MFC after: 2 weeks

The r48589 promised to remove implicit inclusion of if_var.h soon. Prepare
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h

Sponsored by: Netflix
Sponsored by: Nginx, Inc.

Add const qualifier to the dst parameter of the ifnet if_output method.

Remove __FreeBSD_version ifdefs.

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags within sys.

Exceptions:

- sys/contrib not touched
- sys/mbuf.h edited manually

Revert previous commit...

Pointyhat to: kevlo (myself)

Prefer NULL over 0 for pointers

Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.

This means that their use is restricted to a single C file.

Tag mbufs of all incoming frames or packets with the interface's FIB
setting (either default or if supported as set by SIOCSIFFIB, e.g.
from ifconfig).

Submitted by: Alexander V. Chernikov (melifaro ipfw.ru)
Reviewed by: julian
MFC after: 2 weeks

Switch cmd argument to u_long. This matches what if_ethersubr.c does and
allows the code to compile cleanly on amd64 with clang.

Reviewed by: rwatson
Approved by: ed (mentor)

The llentry *lle is only used in cases of INET or INET6.
Put the variable declaration under proper #ifdefs.

In case variables are only needed for one of the two AFs
more them into proper scope.

remove call to IFQ_HANDOFF is it called by if_transmit in the default case
and doing so allows the ifnet driver to define its own queueing mechanism

Change if_output to take a struct route as its fourth argument in order
to allow passing a cached struct llentry * down to L2

Reviewed by: rwatson

Remove the rt argument from nd6_storelladdr() because
rt is no longer accessed.

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

Make compile without INET.

MFC after: 2 months

Retire the MALLOC and FREE macros. They are an abomination unto style(9).

MFC after: 3 months

Use ANSI C function protypes and declarations for if_arcsubr.

MFC after: 1 month

Return mbuf pointer or NULL from ip_fastforward() as the mbuf pointer
may have changed by m_pullup() during fastforward processing.

While this is a bug it is actually never triggered in real world
situations and it is not remotely exploitable.

Found by: Coverity Prevent(tm)
Coverity ID: CID780
Sponsored by: TCP/IP Optimization Fundraise 2005

- Store pointer to the link-level address right in "struct ifnet"
rather than in ifindex_table[]; all (except one) accesses are
through ifp anyway. IF_LLADDR() works faster, and all (except
one) ifaddr_byindex() users were converted to use ifp->if_addr.

- Stop storing a (pointer to) Ethernet address in "struct arpcom",
and drop the IFP2ENADDR() macro; all users have been converted
to use IF_LLADDR() instead.

Propagate rename of IFF_OACTIVE and IFF_RUNNING to IFF_DRV_OACTIVE and
IFF_DRV_RUNNING, as well as the move from ifnet.if_flags to
ifnet.if_drv_flags. Device drivers are now responsible for
synchronizing access to these flags, as they are in if_drv_flags. This
helps prevent races between the network stack and device driver in
maintaining the interface flags field.

Many __FreeBSD__ and __FreeBSD_version checks maintained and continued;
some less so.

Reviewed by: pjd, bz
MFC after: 7 days

When allocating link layer ifnet address list entries in
ifp->if_resolvemulti(), do so with M_NOWAIT rather than M_WAITOK, so
that a mutex can be held over the call. In the FDDI code, add a
missing M_ZERO. Consumers are already aware that if_resolvemulti()
can fail.

MFC after: 1 week

Stop embedding struct ifnet at the top of driver softcs. Instead the
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.

This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.

Other changes of note:
- Struct arpcom is no longer referenced in normal interface code.
Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
To enforce this ac_enaddr has been renamed to _ac_enaddr.
- The second argument to ether_ifattach is now always the mac address
from driver private storage rather than sometimes being ac_enaddr.

Reviewed by: sobomax, sam

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

Prefer C99's __func__ over GCC's __FUNCTION__.

Replace IF_HANDOFF with new IFQ_HANDOFF to enqueue with ALTQ once enabled on
the respective drivers.

add missing #include <sys/module.h>

This commit does two things:

1. rt_check() cleanup:
rt_check() is only necessary for some address families to gain access
to the corresponding arp entry, so call it only in/near the *resolve()
routines where it is actually used -- at the moment this is
arpresolve(), nd6_storelladdr() (the call is embedded here),
and atmresolve() (the call is just before atmresolve to reduce
the number of changes).
This change will make it a lot easier to decouple the arp table
from the routing table.

There is an extra call to rt_check() in if_iso88025subr.c to
determine the routing info length. I have left it alone for
the time being.

The interface of arpresolve() and nd6_storelladdr() now changes slightly:
+ the 'rtentry' parameter (really a hint from the upper level layer)
is now passed unchanged from *_output(), so it becomes the route
to the final destination and not to the gateway.
+ the routines will return 0 if resolution is possible, non-zero
otherwise.
+ arpresolve() returns EWOULDBLOCK in case the mbuf is being held
waiting for an arp reply -- in this case the error code is masked
in the caller so the upper layer protocol will not see a failure.

2. arpcom untangling
Where possible, use 'struct ifnet' instead of 'struct arpcom' variables,
and use the IFP2AC macro to access arpcom fields.
This mostly affects the netatalk code.

=== Detailed changes: ===
net/if_arcsubr.c
rt_check() cleanup, remove a useless variable

net/if_atmsubr.c
rt_check() cleanup

net/if_ethersubr.c
rt_check() cleanup, arpcom untangling

net/if_fddisubr.c
rt_check() cleanup, arpcom untangling

net/if_iso88025subr.c
rt_check() cleanup

netatalk/aarp.c
arpcom untangling, remove a block of duplicated code

netatalk/at_extern.h
arpcom untangling

netinet/if_ether.c
rt_check() cleanup (change arpresolve)

netinet6/nd6.c
rt_check() cleanup (change nd6_storelladdr)

whoops, forgot to fix these places where arpresolve() was used

Detected by: tinderbox

MAC addresses are 8 bits in ARCNET. Adjust bcopy().

- Correct variable name.
- Correct unnecessary use of htons().

Reported by: many.

Handle AF_ARP.

Introduce ip_fastforward and remove ip_flow.

Short description of ip_fastforward:

o adds full direct process-to-completion IPv4 forwarding code
o handles ip fragmentation incl. hw support (ip_flow did not)
o sends icmp needfrag to source if DF is set (ip_flow did not)
o supports ipfw and ipfilter (ip_flow did not)
o supports divert, ipfw fwd and ipfilter nat (ip_flow did not)
o returns anything it can't handle back to normal ip_input

Enable with sysctl -w net.inet.ip.fastforwarding=1

Reviewed by: sam (mentor)

Replace the if_name and if_unit members of struct ifnet with new members
if_xname, if_dname, and if_dunit. if_xname is the name of the interface
and if_dname/unit are the driver name and instance.

This change paves the way for interface renaming and enhanced pseudo
device creation and configuration symantics.

Approved By: re (in principle)
Reviewed By: njl, imp
Tested On: i386, amd64, sparc64
Obtained From: NetBSD (if_xname)

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

Reduce code duplication. This adds the function rt_check() to route.c.

Approved by: sam (in principle)

Back out M_* changes, per decision of the TRB.

Approved by: trb

- bpf is now working (tested with tcpdump)
- fix promiscious mode

MFC after: 3 days

- add support for IPX (tested with mount -t nwfs and mars_nwe),
IP fast forwarding, SIOCGIFADDR, setting hardware address (not currently
enabled in cm driver), multicasts (experimental)
- add ARC_MAX_DATA, use IF_HANDOFF, remove arc_sprintf() and some unused
variables
- if_simloop logic is made more similar to ethernet
- drop not ours packets early (if we are not in promiscous mode)

Submitted by: mark tinguely (partially)

Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.

network interface and link layer changes:

o on input don't strip the Ethernet header from packets
o input packet handling is now done with if_input
o track changes to ether_ifattach/ether_ifdetach API
o track changes to bpf tapping
o call ether_ioctl for default handling of ioctl's
o use constants from net/ethernet.h where possible

Reviewed by: many
Approved by: re

Use if_printf(ifp, "blah") instead of
printf("%s%d: blah", ifp->if_name, ifp->if_xname).

Be consistent about functions being static.

Spotted by: FlexeLint

Cosmetical change: remove empty line to reduce diffs to RELENG_4

Fix incorrect m_free - m_freem() usage.

Remove __P.

- generic Arcnet framework
- device driver for SMC COM90cx6 Arcnet network adapters

Obtained from: NetBSD