MFC r358592:

Expose ifr_buffer_get_(buffer|length) outside if.c.

This is a preparatory commit for D23933.

Reviewed by: jhb
Obtained from: CheriBSD
Sponsored by: DARPA

MFC r356863: ifa_maintain_loopback_route: adjust debugging output

MFC r355070:

Allow kernel to compile without BPF.

r297816 added some bpf magic for VIMAGE unconditionally which no longer
allows kernels to compile without bpf (but with other networking).
Add the missing ifdef checks and allow a kernel to compile without bpf
again.

PR: 242136
Reported by: dave mischler.com
MFC after: 2 weeks

MFC r352458:
Add SIOCGIFDOWNREASON.

Sponsored by: Mellanox Technologies

MFC r352246: SIOCSIFNAME: Do nothing if we're not actually changing

Instead of throwing EEXIST, just succeed if the name isn't actually
changing. We don't need to trigger departure or any of that because there's
no change from consumers' perspective.

PR: 240539

MFC r339012:
For changing the MTU on tun/tap devices, it should not matter whether it
is done via using ifconfig, which uses a SIOCSIFMTU ioctl() command, or
doing it using a TUNSIFINFO/TAPSIFINFO ioctl() command.
Without this patch, for IPv6 the new MTU is not used when creating routes.
Especially, when initiating TCP connections after increasing the MTU,
the old MTU is still used to compute the MSS.
Thanks to ae@ and bz@ for helping to improve the patch.

Reviewed by: ae@, bz@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D17180

MFC r341008:
Fix possible panic during ifnet detach in rtsock.

The panic can happen, when some application does dump of routing table
using sysctl interface. To prevent this, set IFF_DYING flag in
if_detach_internal() function, when ifnet under lock is removed from
the chain. In sysctl_rtsock() take IFNET_RLOCK_NOSLEEP() to prevent
ifnet detach during routes enumeration. In case, if some interface was
detached in the time before we take the lock, add the check, that ifnet
is not DYING. This prevents access to memory that could be freed after
ifnet is unlinked.

Differential Revision: https://reviews.freebsd.org/D18338

MFC r340066:

Notify that the ifnet will go away, even on vnet shutdown

pf subscribes to ifnet_departure_event events, so it can clean up the
ifg_pf_kif and if_pf_kif pointers in the ifnet.
During vnet shutdown interfaces could go away without sending the event,
so pf ends up cleaning these up as part of its shutdown sequence, which
happens after the ifnet has already been freed.

Send the ifnet_departure_event during vnet shutdown, allowing pf to
clean up correctly.

Sponsored by: Orange Business Services

MFC r312770 and r337854:

After the in_control() changes in r257692, an existing address is
(intentionally) deleted first and then completely added again (so all the
events, announces and hooks are given a chance to run).

This cause an issue with CARP where the existing CARP data structure is
removed together with the last address for a given VHID, which will cause
a subsequent fail when the address is later re-added.

This change fixes this issue by adding a new flag to keep the CARP data
structure when an address is not being removed.

There was an additional issue with IPv6 CARP addresses, where the CARP data
structure would never be removed after a change and lead to VHIDs which
cannot be destroyed.

PR: 229384
Sponsored by: Rubicon Communications, LLC (Netgate)

MFC r332997:

Translate 32-bit ifmedia requests into native ones.

We use transformation rather than accessors as virtually ever driver
implements SIOCGIFMEDIA and all would have to be touched.

Keep the code readable by always performing copies and (possiably no-op)
transforms.

Reviewed by: jhb, kib
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14996

MFC r331622:
Allow to specify PCP on packets not belonging to any VLAN.

Sponsored by: Mellanox Technologies

MFC r332088:

Add 32-bit compat for ioctls that take struct ifgroupreq.

Use an accessor to access ifgr_group and ifgr_groups.

Use an macro CASE_IOC_IFGROUPREQ(cmd) in place of case statements such
as "case SIOCAIFGROUP:". This avoids poluting the switch statements
with large numbers of #ifdefs.

Reviewed by: kib
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14960

MFC r332151:

ifconf(): correct handling of sockaddrs smaller than struct sockaddr.

Portable programs that use SIOCGIFCONF (e.g. traceroute) assume
that each pseudo ifreq is of length MAX(sizeof(struct ifreq),
sizeof(ifr_name) + ifr_addr.sa_len). For short sockaddrs we copied
too much from the source sockaddr resulting in a heap leak.

I believe only one such sockaddr exists (struct sockaddr_sco which
is 8 bytes) and it is unclear if such sockaddrs end up on interfaces
in practice. If it did, the result would be an 8 byte heap leak on
current architectures.

admbugs: 869
Reviewed by: kib
Obtained from: CheriBSD
Security: kernel heap leak
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14981

MFC r332087:

ifconf(): Always zero the whole struct ifreq.

The previous split of zeroing ifr_name and ifr_addr seperately is safe
on current architectures, but would be unsafe if pointers were larger
than 8 bytes. Combining the zeroing adds no real cost (a few
instructions) and makes the security property easier to verify.

Reviewed by: kib, emaste
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14912

MFC r331797:

Use an accessor function to access ifr_data.

This fixes 32-bit compat (no ioctl command defintions are required
as struct ifreq is the same size).

Reviewed by: kib
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14900

MFC r331641, r331644, r332158

r331641:
Fix access to ifru_buffer on freebsd32.

Make all kernel accesses to ifru_buffer go via access functions
which take the process ABI into account and use an appropriate union
to access members in the correct place in struct ifreq.

Reviewed by: kib
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14846

r331644:
Fix a whitespace bug missed in refactoring prior to r331641.

MFC with: r331641

r332158:
Remove the thread argument from ifr_buffer_*() accessors.

They are always used in a context where curthread is the correct thread.
This makes them more similar to the ifr_data_get_ptr() accessor.

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

MFC r325436: RTF_PINNED for an interface

Allow a process to assign an IP address to local ppp interface
even if kernel routing table already has a route to the address in question
installed by some routing daemon (PR 223129).

Also, allow loopback route deletion when stopping a VIMAGE jail (PR 222647).

PR: 222647, 223129
Reviewed by: gnn
Approved by: mav (mentor)
Differential Revision: https://reviews.freebsd.org/D12747

MFC 323170

if: Add ioctls to get RSS key and hash type/function.

It will be needed by hn(4) to configure its RSS key and hash
type/function in the transparent VF mode in order to match VF's
RSS settings. The description of the transparent VF mode and
the RSS hash value issue are here:
https://svnweb.freebsd.org/base?view=revision&revision=322299
https://svnweb.freebsd.org/base?view=revision&revision=322485

These are generic enough to promise two independent IOCs instead
of abusing SIOCGDRVSPEC.

Setting RSS key and hash type/function is a different story,
which probably requires more discussion.

Comment about UDP_{IPV4,IPV6,IPV6_EX} were only in the patch
in the review request; these hash types are standardized now.

Reviewed by: gallatin
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D12174

MFC r318160, 318176: Persistently store NIC's hardware MAC address, and add
a way to retrive it

The MAC address reported by `ifconfig ${nic} ether' does not always match
the address in the hardware, as reported by the driver during attach. In
particular, NICs which are components of a lagg(4) interface all report the
same MAC.

When attaching, the NIC driver passes the MAC address it read from the
hardware as an argument to ether_ifattach(). Keep a second copy of it, and
create ioctl(SIOCGHWADDR) to return it. Teach `ifconfig' to report it along
with the active MAC address.

PR: 194386

MFC: 312687, 312916

Approved by: sephe (mentor)

r312687
ifnet: introduce event handlers for ifup/ifdown events

Hyper-V's NIC SR-IOV implementation needs a Hyper-V synthetic NIC and
a VF NIC to work together, mainly to support seamless live migration.

When the VF device becomes UP (or DOWN), the synthetic NIC driver needs
to switch the data path from the synthetic NIC to the VF (or the opposite).

So the synthetic NIC driver needs to know when a VF device is becoming
UP or DOWN and hence the patch is made.

Reviewed by: sephe
Approved by: sephe (mentor)
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D8963

r312916
ifnet: move the new ifnet_event EVENTHANDLER_DECLARE to net/if_var.h

Thank glebius for pointing this out:
"The network stuff shall not be added to sys/eventhandler.h"

Reviewed by: David_A_Bright_DELL.com, sephe, glebius
Approved by: sephe (mentor)
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D9345

revert the MFC r314085

Sorry, I generated a wrong commit log for r314085 due to a copy&pasate mistake.
Let me revert it and I'll redo the MFC.

MFC: 312687, 312688

Approved by: sephe (mentor)

r312687
ifnet: introduce event handlers for ifup/ifdown events

Hyper-V's NIC SR-IOV implementation needs a Hyper-V synthetic NIC and
a VF NIC to work together, mainly to support seamless live migration.

When the VF device becomes UP (or DOWN), the synthetic NIC driver needs
to switch the data path from the synthetic NIC to the VF (or the opposite).

So the synthetic NIC driver needs to know when a VF device is becoming
UP or DOWN and hence the patch is made.

Reviewed by: sephe
Approved by: sephe (mentor)
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D8963

r312688
hyperv/hn: add the support for VF drivers (SR-IOV)

Hyper-V's NIC SR-IOV implementation needs a Hyper-V synthetic NIC and
a VF NIC to work together (both NICs have the same MAC address), mainly to
support seamless live migration.

When the VF device becomes UP (or DOWN), the synthetic NIC driver needs
to switch the data path from the synthetic NIC to the VF (or the opposite).

Note: multicast/broadcast packets are still received through the synthetic
NIC and we need to inject the packets through the VF interface (if the VF is
UP), even if the synthetic NIC is DOWN (so we need to force the rxfilter
to be NDIS_PACKET_TYPE_PROMISCUOUS, when the VF is UP).

Reviewed by: sephe
Approved by: sephe (mentor)
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D8964

MFC 311475

if: Defer the if_up until the ifnet.if_ioctl is called.

This ensures the interface is initialized by the interface driver
before it can be used by the rest of the system.

Reviewed by: jhb, karels, gnn
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D8905

MFC 307078

ifnet: Use if_link_state snapshot to invoke ifnet_link_event

So that everyone in this task have consistent view of link state.

Reviewed by: ae
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D8214

Merge r303263:
Partially revert r257696/r257713, which have an issue with writing to user
controlled address. Restore the old code that emulated OSIOCGIFCONF in if.c.

Approved by: re (kib)