the epoch section towards return statement. Since entering epoch
is cheap, it is easier to cover the whole function with epoch,
rather than try to properly maintain its state.
called in syscall context, so it must enter epoch itself. This
changeset originates from early version of the patch, and somehow
slipped to the final version.
Reported by: pho
Acquire the inp lock before checking whether the socket is already bound,
and around updates to the inp_vflag field.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21867
When epoch(9) was introduced to network stack, it was basically
dropped in place of existing locking, which was mutexes and
rwlocks. For the sake of performance mutex covered areas were
as small as possible, so became epoch covered areas.
However, epoch doesn't introduce any contention, it just delays
memory reclaim. So, there is no point to minimise epoch covered
areas in sense of performance. Meanwhile entering/exiting epoch
also has non-zero CPU usage, so doing this less often is a win.
Not the least is also code maintainability. In the new paradigm
we can assume that at any stage of processing a packet, we are
inside network epoch. This makes coding both input and output
path way easier.
On output path we already enter epoch quite early - in the
ip_output(), in the ip6_output().
This patch does the same for the input path. All ISR processing,
network related callouts, other ways of packet injection to the
network stack shall be performed in net_epoch. Any leaf function
that walks network configuration now asserts epoch.
Tricky part is configuration code paths - ioctls, sysctls. They
also call into leaf functions, so some need to be changed.
This patch would introduce more epoch recursions (see EPOCH_TRACE)
than we had before. They will be cleaned up separately, as several
of them aren't trivial. Note, that unlike a lock recursion the
epoch recursion is safe and just wastes a bit of resources.
Reviewed by: gallatin, hselasky, cy, adrian, kristof
Differential Revision: https://reviews.freebsd.org/D19111
contains Hop-by-Hop options, the mbuf chain is potentially changed in
ip6_hopopts_input(), called by ip6_input_hbh().
This can happen, because of the the use of IP6_EXTHDR_CHECK, which might
call m_pullup().
So provide the updated pointer back to the called of ip6_input_hbh() to
avoid using a freed mbuf chain in`ip6_input()`.
Reviewed by: markj@
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D21664
KTLS adds support for in-kernel framing and encryption of Transport
Layer Security (1.0-1.2) data on TCP sockets. KTLS only supports
offload of TLS for transmitted data. Key negotation must still be
performed in userland. Once completed, transmit session keys for a
connection are provided to the kernel via a new TCP_TXTLS_ENABLE
socket option. All subsequent data transmitted on the socket is
placed into TLS frames and encrypted using the supplied keys.
Any data written to a KTLS-enabled socket via write(2), aio_write(2),
or sendfile(2) is assumed to be application data and is encoded in TLS
frames with an application data type. Individual records can be sent
with a custom type (e.g. handshake messages) via sendmsg(2) with a new
control message (TLS_SET_RECORD_TYPE) specifying the record type.
At present, rekeying is not supported though the in-kernel framework
should support rekeying.
KTLS makes use of the recently added unmapped mbufs to store TLS
frames in the socket buffer. Each TLS frame is described by a single
ext_pgs mbuf. The ext_pgs structure contains the header of the TLS
record (and trailer for encrypted records) as well as references to
the associated TLS session.
KTLS supports two primary methods of encrypting TLS frames: software
TLS and ifnet TLS.
Software TLS marks mbufs holding socket data as not ready via
M_NOTREADY similar to sendfile(2) when TLS framing information is
added to an unmapped mbuf in ktls_frame(). ktls_enqueue() is then
called to schedule TLS frames for encryption. In the case of
sendfile_iodone() calls ktls_enqueue() instead of pru_ready() leaving
the mbufs marked M_NOTREADY until encryption is completed. For other
writes (vn_sendfile when pages are available, write(2), etc.), the
PRUS_NOTREADY is set when invoking pru_send() along with invoking
ktls_enqueue().
A pool of worker threads (the "KTLS" kernel process) encrypts TLS
frames queued via ktls_enqueue(). Each TLS frame is temporarily
mapped using the direct map and passed to a software encryption
backend to perform the actual encryption.
(Note: The use of PHYS_TO_DMAP could be replaced with sf_bufs if
someone wished to make this work on architectures without a direct
map.)
KTLS supports pluggable software encryption backends. Internally,
Netflix uses proprietary pure-software backends. This commit includes
a simple backend in a new ktls_ocf.ko module that uses the kernel's
OpenCrypto framework to provide AES-GCM encryption of TLS frames. As
a result, software TLS is now a bit of a misnomer as it can make use
of hardware crypto accelerators.
Once software encryption has finished, the TLS frame mbufs are marked
ready via pru_ready(). At this point, the encrypted data appears as
regular payload to the TCP stack stored in unmapped mbufs.
ifnet TLS permits a NIC to offload the TLS encryption and TCP
segmentation. In this mode, a new send tag type (IF_SND_TAG_TYPE_TLS)
is allocated on the interface a socket is routed over and associated
with a TLS session. TLS records for a TLS session using ifnet TLS are
not marked M_NOTREADY but are passed down the stack unencrypted. The
ip_output_send() and ip6_output_send() helper functions that apply
send tags to outbound IP packets verify that the send tag of the TLS
record matches the outbound interface. If so, the packet is tagged
with the TLS send tag and sent to the interface. The NIC device
driver must recognize packets with the TLS send tag and schedule them
for TLS encryption and TCP segmentation. If the the outbound
interface does not match the interface in the TLS send tag, the packet
is dropped. In addition, a task is scheduled to refresh the TLS send
tag for the TLS session. If a new TLS send tag cannot be allocated,
the connection is dropped. If a new TLS send tag is allocated,
however, subsequent packets will be tagged with the correct TLS send
tag. (This latter case has been tested by configuring both ports of a
Chelsio T6 in a lagg and failing over from one port to another. As
the connections migrated to the new port, new TLS send tags were
allocated for the new port and connections resumed without being
dropped.)
ifnet TLS can be enabled and disabled on supported network interfaces
via new '[-]txtls[46]' options to ifconfig(8). ifnet TLS is supported
across both vlan devices and lagg interfaces using failover, lacp with
flowid enabled, or lacp with flowid enabled.
Applications may request the current KTLS mode of a connection via a
new TCP_TXTLS_MODE socket option. They can also use this socket
option to toggle between software and ifnet TLS modes.
In addition, a testing tool is available in tools/tools/switch_tls.
This is modeled on tcpdrop and uses similar syntax. However, instead
of dropping connections, -s is used to force KTLS connections to
switch to software TLS and -i is used to switch to ifnet TLS.
Various sysctls and counters are available under the kern.ipc.tls
sysctl node. The kern.ipc.tls.enable node must be set to true to
enable KTLS (it is off by default). The use of unmapped mbufs must
also be enabled via kern.ipc.mb_use_ext_pgs to enable KTLS.
KTLS is enabled via the KERN_TLS kernel option.
This patch is the culmination of years of work by several folks
including Scott Long and Randall Stewart for the original design and
implementation; Drew Gallatin for several optimizations including the
use of ext_pgs mbufs, the M_NOTREADY mechanism for TLS records
awaiting software encryption, and pluggable software crypto backends;
and John Baldwin for modifications to support hardware TLS offload.
Reviewed by: gallatin, hselasky, rrs
Obtained from: Netflix
Sponsored by: Netflix, Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D21277
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
Consitently put () around return values.
Do not assign variables at the time of variable declaration.
Sort variables. Rename ia to ia6, remove/reuse some variables used only
once or twice for temporary calculations.
No functional changes intended.
MFC after: 3 months
Sponsored by: Netflix
Cleanup some comments (start with upper case, ends in punctuation,
use width and do not consume vertical space). Update comments to
RFC8200. Some whitespace changes.
No functional changes.
MFC after: 3 months
Sponsored by: Netflix
Previously the ICMPv6 input path incorrectly handled cases where an
MLDv2 listener query packet was internally fragmented across multiple
mbufs.
admbugs: 921
Submitted by: jtl
Reported by: CJD of Apple
Approved by: so
MFC after: 0 minutes
Security: CVE-2019-5608
The hash buckets array is called ip6q. The data structure ip6q is a
description of different object, the one the array holds these days
(since r337776). To clear some of this confusion, rename the array
to ip6qb.
When iterating over all buckets or addressing them directly, we
use at least the variables i, hash, and bucket. To keep the
terminology consistent use the variable name "bucket" and always
make it an uint32_t and not sometimes an int.
No functional behaviour changes intended.
MFC after: 3 months
Sponsored by: Netflix
Re-order functions within the file in preparation for an upcoming
code simplification.
No functional changes.
MFC after: 3 months
Sponsored by: Netflix
Bring back systm.h after r350532 and banish errno.h, time.h, and
machine/atomic.h.
Reported by: bde (Thank you!)
Pointyhat to: bz
MFC after: 12 weeks
X-MFC: with r350532
Sponsored by: Netflix
Removing the prototype from the header and making the function static
in r350533 makes architectures using gcc complain "function declaration
isn't a prototype". Add the missing void given the function has no
arguments.
Reported by: the CI machinery
Pointyhat to: bz
MFC after: 3 months
X-MFC with: r350533
Sponsored by: Netflix
Rename M_FTABLE to M_FRAG6 as the former sounds very much like the former
"flowtable" rather than anything to do with fragments and reassembly.
While here, let malloc( , .. | M_ZERO) do the zeroing rather than calling
bzero() ourselves.
MFC after: 3 months
Sponsored by: Netflix
Remove all the #if 0 and #if notyet blocks of dead code which have been
there for at least 18 years from what I can see.
No functional changes.
MFC after: 3 months
Sponsored by: Netflix
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
Sort includes and remove duplicate kernel.h as well as the unneeded
systm.h.
Hide the mac framework incude behind #fidef MAC.
MFC after: 3 months
Sponsored by: Netflix
Finish what was started a few years ago and harmonize IPv6 and IPv4
kernel names. We are down to very few places now that it is feasible
to do the change for everything remaining with causing too much disturbance.
Remove "aliases" for IPv6 names which confusingly could indicate
that we are talking about a different data structure or field or
have two fields, one for each address family.
Try to follow common conventions used in FreeBSD.
* Rename sin6p to sin6 as that is how it is spelt in most places.
* Remove "aliases" (#defines) for:
- in6pcb which really is an inpcb and nothing separate
- sotoin6pcb which is sotoinpcb (as per above)
- in6p_sp which is inp_sp
- in6p_flowinfo which is inp_flow
* Try to use ia6 for in6_addr rather than in6p.
* With all these gone also rename the in6p variables to inp as
that is what we call it in most of the network stack including
parts of netinet6.
The reasons behind this cleanup are that we try to further
unify netinet and netinet6 code where possible and that people
will less ignore one or the other protocol family when doing
code changes as they may not have spotted places due to different
names for the same thing.
No functional changes.
Discussed with: tuexen (SCTP changes)
MFC after: 3 months
Sponsored by: Netflix
Unmapped mbufs allow sendfile to carry multiple pages of data in a
single mbuf, without mapping those pages. It is a requirement for
Netflix's in-kernel TLS, and provides a 5-10% CPU savings on heavy web
serving workloads when used by sendfile, due to effectively
compressing socket buffers by an order of magnitude, and hence
reducing cache misses.
For this new external mbuf buffer type (EXT_PGS), the ext_buf pointer
now points to a struct mbuf_ext_pgs structure instead of a data
buffer. This structure contains an array of physical addresses (this
reduces cache misses compared to an earlier version that stored an
array of vm_page_t pointers). It also stores additional fields needed
for in-kernel TLS such as the TLS header and trailer data that are
currently unused. To more easily detect these mbufs, the M_NOMAP flag
is set in m_flags in addition to M_EXT.
Various functions like m_copydata() have been updated to safely access
packet contents (using uiomove_fromphys()), to make things like BPF
safe.
NIC drivers advertise support for unmapped mbufs on transmit via a new
IFCAP_NOMAP capability. This capability can be toggled via the new
'nomap' and '-nomap' ifconfig(8) commands. For NIC drivers that only
transmit packet contents via DMA and use bus_dma, adding the
capability to if_capabilities and if_capenable should be all that is
required.
If a NIC does not support unmapped mbufs, they are converted to a
chain of mapped mbufs (using sf_bufs to provide the mapping) in
ip_output or ip6_output. If an unmapped mbuf requires software
checksums, it is also converted to a chain of mapped mbufs before
computing the checksum.
Submitted by: gallatin (earlier version)
Reviewed by: gallatin, hselasky, rrs
Discussed with: ae, kp (firewalls)
Relnotes: yes
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20616
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
- Perform ifp mismatch checks (to determine if a send tag is allocated
for a different ifp than the one the packet is being output on), in
ip_output() and ip6_output(). This avoids sending packets with send
tags to ifnet drivers that don't support send tags.
Since we are now checking for ifp mismatches before invoking
if_output, we can now try to allocate a new tag before invoking
if_output sending the original packet on the new tag if allocation
succeeds.
To avoid code duplication for the fragment and unfragmented cases,
add ip_output_send() and ip6_output_send() as wrappers around
if_output and nd6_output_ifp, respectively. All of the logic for
setting send tags and dealing with send tag-related errors is done
in these wrapper functions.
For pseudo interfaces that wrap other network interfaces (vlan and
lagg), wrapper send tags are now allocated so that ip*_output see
the wrapper ifp as the ifp in the send tag. The if_transmit
routines rewrite the send tags after performing an ifp mismatch
check. If an ifp mismatch is detected, the transmit routines fail
with EAGAIN.
- To provide clearer life cycle management of send tags, especially
in the presence of vlan and lagg wrapper tags, add a reference count
to send tags managed via m_snd_tag_ref() and m_snd_tag_rele().
Provide a helper function (m_snd_tag_init()) for use by drivers
supporting send tags. m_snd_tag_init() takes care of the if_ref
on the ifp meaning that code alloating send tags via if_snd_tag_alloc
no longer has to manage that manually. Similarly, m_snd_tag_rele
drops the refcount on the ifp after invoking if_snd_tag_free when
the last reference to a send tag is dropped.
This also closes use after free races if there are pending packets in
driver tx rings after the socket is closed (e.g. from tcpdrop).
In order for m_free to work reliably, add a new CSUM_SND_TAG flag in
csum_flags to indicate 'snd_tag' is set (rather than 'rcvif').
Drivers now also check this flag instead of checking snd_tag against
NULL. This avoids false positive matches when a forwarded packet
has a non-NULL rcvif that was treated as a send tag.
- cxgbe was relying on snd_tag_free being called when the inp was
detached so that it could kick the firmware to flush any pending
work on the flow. This is because the driver doesn't require ACK
messages from the firmware for every request, but instead does a
kind of manual interrupt coalescing by only setting a flag to
request a completion on a subset of requests. If all of the
in-flight requests don't have the flag when the tag is detached from
the inp, the flow might never return the credits. The current
snd_tag_free command issues a flush command to force the credits to
return. However, the credit return is what also frees the mbufs,
and since those mbufs now hold references on the tag, this meant
that snd_tag_free would never be called.
To fix, explicitly drop the mbuf's reference on the snd tag when the
mbuf is queued in the firmware work queue. This means that once the
inp's reference on the tag goes away and all in-flight mbufs have
been queued to the firmware, tag's refcount will drop to zero and
snd_tag_free will kick in and send the flush request. Note that we
need to avoid doing this in the middle of ethofld_tx(), so the
driver grabs a temporary reference on the tag around that loop to
defer the free to the end of the function in case it sends the last
mbuf to the queue after the inp has dropped its reference on the
tag.
- mlx5 preallocates send tags and was using the ifp pointer even when
the send tag wasn't in use. Explicitly use the ifp from other data
structures instead.
- Sprinkle some assertions in various places to assert that received
packets don't have a send tag, and that other places that overwrite
rcvif (e.g. 802.11 transmit) don't clobber a send tag pointer.
Reviewed by: gallatin, hselasky, rgrimes, ae
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20117
since r286195.
Do not forget results of route lookup and initialize rt and ifp pointers.
PR: 238098
Submitted by: Masse Nicolas <nicolas.masse at stormshield eu>
MFC after: 1 week
Currently rinit1() and its IPv6 counterpart
nd6_prefix_onlink_rtrequest() uses dummy null_sdl gateway address
during route insertion and change it afterwards. This behaviour
brings complications to the routing stack and the users of its
upcoming notification system.
This change fixes both rinit1() and nd6_prefix_onlink_rtrequest()
by filling in proper gateway in the beginning. It does not change any
of the userland notifications as in both cases, they happen after
the insertion and fixup process (rt_newaddrmsg_fib() and nd6_rtmsg()).
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D20328
This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces header
pollution substantially.
EVENTHANDLER_DECLARE and EVENTHANDLER_LIST_DECLAREs were moved out of .c
files into appropriate headers (e.g., sys/proc.h, powernv/opal.h).
As a side effect of reduced header pollution, many .c files and headers no
longer contain needed definitions. The remainder of the patch addresses
adding appropriate includes to fix those files.
LOCK_DEBUG and LOCK_FILE_LINE_ARG are moved to sys/_lock.h, as required by
sys/mutex.h since r326106 (but silently protected by header pollution prior
to this change).
No functional change (intended). Of course, any out of tree modules that
relied on header pollution for sys/eventhandler.h, sys/lock.h, or
sys/mutex.h inclusion need to be fixed. __FreeBSD_version has been bumped.
in RFC 4620, ICMPv6 Node Information Queries. A vnet jail with an
IPv6 address sent a hostname of the host environment, not the
jail, even if another hostname was set to the jail.
This change can be tested by the following commands:
# ifconfig epair0 create
# jail -c -n j1 vnet host.hostname=vnetjail path=/ persist
# ifconfig epair0b vnet j1
# ifconfig epair0a inet6 -ifdisabled auto_linklocal up
# jexec j1 ifconfig epair0b inet6 -ifdisabled auto_linklocal up
# ping6 -w ff02::1%epair0a
Differential Revision: https://reviews.freebsd.org/D20207
MFC after: 1 week
r333175 converted the global multicast lock to a sleepable sx lock,
so the lock order with respect to the (non-sleepable) inp lock changed.
To handle this, r333175 and r333505 added code to drop the inp lock,
but this opened races that could leave multicast group description
structures in an inconsistent state. This change fixes the problem by
simply acquiring the global lock sooner. Along the way, this fixes
some LORs and bogus error handling introduced in r333175, and commits
some related cleanup.
Reported by: syzbot+ba7c4943547e0604faca@syzkaller.appspotmail.com
Reported by: syzbot+1b803796ab94d11a46f9@syzkaller.appspotmail.com
Reviewed by: ae
MFC after: 3 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D20070
This uses m_dup_pkthdr() to copy all of the metadata about a packet to
each of its fragments including VLAN tags, mbuf tags, etc. instead of
hand-copying a few fields.
Reviewed by: bz
MFC after: 1 month
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20117
Drivers can now pass up numa domain information via the
mbuf numa domain field. This information is then used
by TCP syncache_socket() to associate that information
with the inpcb. The domain information is then fed back
into transmitted mbufs in ip{6}_output(). This mechanism
is nearly identical to what is done to track RSS hash values
in the inp_flowid.
Follow on changes will use this information for lacp egress
port selection, binding TCP pacers to the appropriate NUMA
domain, etc.
Reviewed by: markj, kib, slavash, bz, scottl, jtl, tuexen
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D20028
This GRE-in-UDP encapsulation allows the UDP source port field to be
used as an entropy field for load-balancing of GRE traffic in transit
networks. Also most of multiqueue network cards are able distribute
incoming UDP datagrams to different NIC queues, while very little are
able do this for GRE packets.
When an administrator enables UDP encapsulation with command
`ifconfig gre0 udpencap`, the driver creates kernel socket, that binds
to tunnel source address and after udp_set_kernel_tunneling() starts
receiving of all UDP packets destined to 4754 port. Each kernel socket
maintains list of tunnels with different destination addresses. Thus
when several tunnels use the same source address, they all handled by
single socket. The IP[V6]_BINDANY socket option is used to be able bind
socket to source address even if it is not yet available in the system.
This may happen on system boot, when gre(4) interface is created before
source address become available. The encapsulation and sending of packets
is done directly from gre(4) into ip[6]_output() without using sockets.
Reviewed by: eugen
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D19921
If kern.random.initial_seeding.bypass_before_seeding is disabled, random(4)
and arc4random(9) will block indefinitely until enough entropy is available
to initially seed Fortuna.
It seems that zero flowids are perfectly valid, so avoid blocking on random
until initial seeding takes place.
Discussed with: bz (earlier revision)
Reviewed by: thj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D20011
RFC 4391 specifies that the IB interface GID should be re-used as IPv6
link-local address. Since the code in in6_get_hw_ifid() ignored
IFT_INFINIBAND case, ibX interfaces ended up with the local address
borrowed from some other interface, which is non-compliant.
Use lowest eight bytes from GID for filling the link-local address,
same as Linux.
Reviewed by: bz (previous version), ae, hselasky, slavash,
Sponsored by: Mellanox Technologies
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D20006
fragmented packets.
When sending IPv4 and IPv6 fragmented packets and a fragment is lost,
the mbuf making up the fragment will remain in the temporary hashed
fragment list for a while. If the network interface departs before the
so-called slow timeout clears the packet, the fragment causes a panic
when the timeout kicks in due to accessing a freed network interface
structure.
Make sure that when a network device is departing, all hashed IPv4 and
IPv6 fragments belonging to it, get freed.
Backtrace:
panic()
icmp6_reflect()
hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim;
^^^^ rcvif->if_afdata[AF_INET6] is NULL.
icmp6_error()
frag6_freef()
frag6_slowtimo()
pfslowtimo()
softclock_call_cc()
softclock()
ithread_loop()
Differential Revision: https://reviews.freebsd.org/D19622
Reviewed by: bz (network), adrian
MFC after: 1 week
Sponsored by: Mellanox Technologies
IPPROTO_IPV6 level socket option IPV6_CHECKSUM enabled and the
checksum check fails, drop the message. Without this fix, an
ICMP6 message was sent indicating a parameter problem.
Thanks to bz@ for suggesting a way to simplify this fix.
Reviewed by: bz@
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D19969
is requested by the application using the IPPROTO_IPV6 level socket option
IPV6_CHECKSUM on a raw socket, ensure that the packet contains enough
bytes to contain the checksum at the specified offset.
Reported by: syzbot+6295fcc5a8aced81d599@syzkaller.appspotmail.com
Reviewed by: bz@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D19968
as requested by the user via the IPPROTO_IPV6 level socket option
IPV6_CHECKSUM. The check if there are enough bytes in the packet to
store the checksum at the requested offset was wrong by 1.
Reviewed by: bz@
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D19967
When using the IPPROTO_IPV6 level socket option IPV6_CHECKSUM on a raw
IPv6 socket, ensure that the value is either -1 or a non-negative even
number.
Reviewed by: bz@, thj@
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D19966
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
When leaving a multicast group, a hole may be created in the inpcb's
source filter and group membership arrays. To remove the hole, the
succeeding array elements are copied over by one entry. The multicast
code expects that a newly allocated array element is initialized, but
the code which shifts a tail of the array was leaving stale data
in the final entry. Fix this by explicitly reinitializing the last
entry following such a copy.
Reported by: syzbot+f8c3c564ee21d650475e@syzkaller.appspotmail.com
Reviewed by: ae
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19872
stf(4) interfaces are not multicast-capable so they can't perform DAD.
They also did not set IFF_DRV_RUNNING when an address was assigned, so
the logic in nd6_timer() would periodically flag such an address as
tentative, resulting in interface flapping.
Fix the problem by setting IFF_DRV_RUNNING when an address is assigned,
and do some related cleanup:
- In in6if_do_dad(), remove a redundant check for !UP || !RUNNING.
There is only one caller in the tree, and it only looks at whether
the return value is non-zero.
- Have in6if_do_dad() return false if the interface is not
multicast-capable.
- Set ND6_IFF_NO_DAD when an address is assigned to an stf(4) interface
and the interface goes UP as a result. Note that this is not
sufficient to fix the problem because the new address is marked as
tentative and DAD is started before in6_ifattach() is called.
However, setting no_dad is formally correct.
- Change nd6_timer() to not flag addresses as tentative if no_dad is
set.
This is based on a patch from Viktor Dukhovni.
Reported by: Viktor Dukhovni <ietf-dane@dukhovni.org>
Reviewed by: ae
MFC after: 3 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19751
Update NAT64LSN implementation:
o most of data structures and relations were modified to be able support
large number of translation states. Now each supported protocol can
use full ports range. Ports groups now are belongs to IPv4 alias
addresses, not hosts. Each ports group can keep several states chunks.
This is controlled with new `states_chunks` config option. States
chunks allow to have several translation states for single alias address
and port, but for different destination addresses.
o by default all hash tables now use jenkins hash.
o ConcurrencyKit and epoch(9) is used to make NAT64LSN lockless on fast path.
o one NAT64LSN instance now can be used to handle several IPv6 prefixes,
special prefix "::" value should be used for this purpose when instance
is created.
o due to modified internal data structures relations, the socket opcode
that does states listing was changed.
Obtained from: Yandex LLC
MFC after: 1 month
Sponsored by: Yandex LLC
o most of data structures and relations were modified to be able support
large number of translation states. Now each supported protocol can
use full ports range. Ports groups now are belongs to IPv4 alias
addresses, not hosts. Each ports group can keep several states chunks.
This is controlled with new `states_chunks` config option. States
chunks allow to have several translation states for single alias address
and port, but for different destination addresses.
o by default all hash tables now use jenkins hash.
o ConcurrencyKit and epoch(9) is used to make NAT64LSN lockless on fast path.
o one NAT64LSN instance now can be used to handle several IPv6 prefixes,
special prefix "::" value should be used for this purpose when instance
is created.
o due to modified internal data structures relations, the socket opcode
that does states listing was changed.
Obtained from: Yandex LLC
MFC after: 1 month
Sponsored by: Yandex LLC
CLAT is customer-side translator that algorithmically translates 1:1
private IPv4 addresses to global IPv6 addresses, and vice versa.
It is implemented as part of ipfw_nat64 kernel module. When module
is loaded or compiled into the kernel, it registers "nat64clat" external
action. External action named instance can be created using `create`
command and then used in ipfw rules. The create command accepts two
IPv6 prefixes `plat_prefix` and `clat_prefix`. If plat_prefix is ommitted,
IPv6 NAT64 Well-Known prefix 64:ff9b::/96 will be used.
# ipfw nat64clat CLAT create clat_prefix SRC_PFX plat_prefix DST_PFX
# ipfw add nat64clat CLAT ip4 from IPv4_PFX to any out
# ipfw add nat64clat CLAT ip6 from DST_PFX to SRC_PFX in
Obtained from: Yandex LLC
Submitted by: Boris N. Lytochkin
MFC after: 1 month
Relnotes: yes
Sponsored by: Yandex LLC
Add second IPv6 prefix to generic config structure and rename another
fields to conform to RFC6877. Now it contains two prefixes and length:
PLAT is provider-side translator that translates N:1 global IPv6 addresses
to global IPv4 addresses. CLAT is customer-side translator (XLAT) that
algorithmically translates 1:1 IPv4 addresses to global IPv6 addresses.
Use PLAT prefix in stateless (nat64stl) and stateful (nat64lsn)
translators.
Modify nat64_extract_ip4() and nat64_embed_ip4() functions to accept
prefix length and use plat_plen to specify prefix length.
Retire net.inet.ip.fw.nat64_allow_private sysctl variable.
Add NAT64_ALLOW_PRIVATE flag and use "allow_private" config option to
configure this ability separately for each NAT64 instance.
Obtained from: Yandex LLC
MFC after: 1 month
Sponsored by: Yandex LLC
When we roam between networks and our link-state goes down, automatically remove
the IPv6-Only flag from the interface. Otherwise we might switch from an
IPv6-only to and IPv4-only network and the flag would stay and we would prevent
IPv4 from working.
While the actual function call to clear the flag is under EXPERIMENTAL,
the eventhandler is not as we might want to re-use it for other
functionality on link-down event (such was re-calculate default routers
for example if there is more than one).
Reviewed by: hrs
Differential Revision: https://reviews.freebsd.org/D19487
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.
When dropping a fragment queue, account for the number of fragments in the
queue. This improves accounting between the number of fragments received and
the number of fragments dropped.
Reviewed by: jtl, bz, transport
Approved by: jtl (mentor), bz (mentor)
Differential Revision: https://review.freebsd.org/D17521
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
connectivity.
Looking at past changes in this area like r337866, some refcounting
bugs have been introduced, one by one. For example like calling
in6m_disconnect() and in6m_rele_locked() in mld_v1_process_group_timer()
where previously no disconnect nor refcount decrement was done.
Calling in6m_disconnect() when it shouldn't causes IPv6 solitation to no
longer work, because all the multicast addresses receiving the solitation
messages are now deleted from the network interface.
This patch reverts some recent changes while improving the MLD
refcounting and concurrency model after the MLD code was converted
to using EPOCH(9).
List changes:
- All CK_STAILQ_FOREACH() macros are now properly enclosed into
EPOCH(9) sections. This simplifies assertion of locking inside
in6m_ifmultiaddr_get_inm().
- Corrected bad use of in6m_disconnect() leading to loss of IPv6
connectivity for MLD v1.
- Factored out checks for valid inm structure into
in6m_ifmultiaddr_get_inm().
PR: 233535
Differential Revision: https://reviews.freebsd.org/D18887
Reviewed by: bz (net)
Tested by: ae
MFC after: 1 week
Sponsored by: Mellanox Technologies
because the destructor will access the if_ioctl() callback in the ifnet
pointer which is about to be freed. This prevents use-after-free.
PR: 233535
Differential Revision: https://reviews.freebsd.org/D18887
Reviewed by: bz (net)
Tested by: ae
MFC after: 1 week
Sponsored by: Mellanox Technologies
After the afdata read lock was converted to epoch(9), readers could
observe a linked LLE and block on the LLE while a thread was
unlinking the LLE. The writer would then release the lock and schedule
the LLE for deferred free, allowing readers to continue and potentially
schedule the LLE timer. By the point the timer fires, the structure is
freed, typically resulting in a crash in the callout subsystem.
Fix the problem by modifying the lookup path to check for the LLE_LINKED
flag upon acquiring the LLE lock. If it's not set, the lookup fails.
PR: 234296
Reviewed by: bz
Tested by: sbruno, Victor <chernov_victor@list.ru>,
Mike Andrews <mandrews@bit0.com>
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18906
The loopback interface can only receive packets with a single scope ID,
namely the scope ID of the loopback interface itself. To mitigate this
packets which use the scope ID are appearing as received by the real
network interface, see "origifp" in the patch. The current code would
drop packets which are designated for loopback which use a link-local
scope ID in the destination address or source address, because they
won't match the lo0's scope ID. To fix this restore the network
interface pointer from the scope ID in the destination address for
the problematic cases. See comments added in patch for a more detailed
description.
This issue was introduced with route caching (ae@).
Reviewed by: bz (network)
Differential Revision: https://reviews.freebsd.org/D18769
MFC after: 1 week
Sponsored by: Mellanox Technologies
- Remove macros that covertly create epoch_tracker on thread stack. Such
macros a quite unsafe, e.g. will produce a buggy code if same macro is
used in embedded scopes. Explicitly declare epoch_tracker always.
- Unmask interface list IFNET_RLOCK_NOSLEEP(), interface address list
IF_ADDR_RLOCK() and interface AF specific data IF_AFDATA_RLOCK() read
locking macros to what they actually are - the net_epoch.
Keeping them as is is very misleading. They all are named FOO_RLOCK(),
while they no longer have lock semantics. Now they allow recursion and
what's more important they now no longer guarantee protection against
their companion WLOCK macros.
Note: INP_HASH_RLOCK() has same problems, but not touched by this commit.
This is non functional mechanical change. The only functionally changed
functions are ni6_addrs() and ni6_store_addrs(), where we no longer enter
epoch recursively.
Discussed with: jtl, gallatin
Memory beyond that limit was previously unused, wasting roughly 1MB per
8GB of RAM. Also retire INP_PCBLBGROUP_PORTHASH, which was identical to
INP_PCBPORTHASH.
Reviewed by: glebius
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D17803
Various network protocol sysctl handlers were not zero-filling their
output buffers and thus would export uninitialized stack memory to
userland. Fix a number of such handlers.
Reported by: Thomas Barabosch, Fraunhofer FKIE
Reviewed by: tuexen
MFC after: 3 days
Security: kernel memory disclosure
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18301
Now an interface name can be specified for nptv6 instance instead of
ext_prefix. The module will track if_addr_ext events and when suitable
IPv6 address will be added to specified interface, it will be configured
as external prefix. When address disappears instance becomes unusable,
i.e. it doesn't match any packets.
Reviewed by: 0mp (manpages)
Tested by: Dries Michiels <driesm dot michiels gmail com>
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D17765
If another thread immediately removes the link-local address
added by in6_update_ifa(), in6ifa_ifpforlinklocal() can return NULL,
so the following assertion (or dereference) is wrong.
Remove the assertion, and handle NULL somewhat better than panicking.
This matches all of the other callers of in6_update_ifa().
PR: 219250
Reviewed by: bz, dab (both an earlier version)
MFC after: 1 week
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D17898
This change defines the RA "6" (IPv6-Only) flag which routers
may advertise, kernel logic to check if all routers on a link
have the flag set and accordingly update a per-interface flag.
If all routers agree that it is an IPv6-only link, ether_output_frame(),
based on the interface flag, will filter out all ETHERTYPE_IP/ARP
frames, drop them, and return EAFNOSUPPORT to upper layers.
The change also updates ndp to show the "6" flag, ifconfig to
display the IPV6_ONLY nd6 flag if set, and rtadvd to allow
announcing the flag.
Further changes to tcpdump (contrib code) are availble and will
be upstreamed.
Tested the code (slightly earlier version) with 2 FreeBSD
IPv6 routers, a FreeBSD laptop on ethernet as well as wifi,
and with Win10 and OSX clients (which did not fall over with
the "6" flag set but not understood).
We may also want to (a) implement and RX filter, and (b) over
time enahnce user space to, say, stop dhclient from running
when the interface flag is set. Also we might want to start
IPv6 before IPv4 in the future.
All the code is hidden under the EXPERIMENTAL option and not
compiled by default as the draft is a work-in-progress and
we cannot rely on the fact that IANA will assign the bits
as requested by the draft and hence they may change.
Dear 6man, you have running code.
Discussed with: Bob Hinden, Brian E Carpenter
After r335924 rip6_input() needs inp validation to avoid
working on FREED inps.
Apply the relevant bits from r335497,r335501 (rip_input() change)
to the IPv6 counterpart.
PR: 232194
Reviewed by: rgrimes, ae (,hps)
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D17594
This change is similar to r339646. The callback that checks for appearing
and disappearing of tunnel ingress address can be called during VNET
teardown. To prevent access to already freed memory, add check to the
callback and epoch_wait() call to be sure that callback has finished its
work.
MFC after: 20 days
This should have been a part of r338470. No functional changes
intended.
Reported by: gallatin
Reviewed by: gallatin, Johannes Lundberg <johalun0@gmail.com>
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17109
* register handler for ingress address appearing/disappearing;
* add new srcaddr hash table for fast softc lookup by srcaddr;
* when srcaddr disappears, clear IFF_DRV_RUNNING flag from interface,
and set it otherwise;
MFC after: 1 month
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17214
* register handler for ingress address appearing/disappearing;
* add new srcaddr hash table for fast softc lookup by srcaddr;
* when srcaddr disappears, clear IFF_DRV_RUNNING flag from interface,
and set it otherwise;
* remove the note about ingress address from BUGS section.
MFC after: 1 month
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17134
handler receives the type of event IFADDR_EVENT_ADD/IFADDR_EVENT_DEL,
and the pointer to ifaddr. Also ifaddr_event now is implemented using
ifaddr_event_ext handler.
MFC after: 3 weeks
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D17100
epoch section without exiting that epoch section. This is bad for two
reasons: the epoch section won't exit, and we will leave the epoch tracker
from the stack on the epoch list.
Fix the epoch leak by making sure we exit epoch sections before returning.
Reviewed by: ae, gallatin, mmacy
Approved by: re (gjb, kib)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D17450
using an application trying to use a v4mapped destination address on a
kernel without INET support or on a v6only socket.
Catch this case and prevent the packet from going anywhere;
else, without the KASSERT() armed, a v4mapped destination
address might go out on the wire or other undefined behaviour
might happen, while with the KASSERT() we panic.
PR: 231728
Reported by: Jeremy Faulkner (gldisater gmail.com)
Approved by: re (kib)
once we have a lock, make sure the inp is not marked freed.
This can happen since the list traversal and locking was
converted to epoch(9). If the inp is marked "freed", skip it.
This prevents a NULL pointer deref panic later on.
Reported by: slavash (Mellanox)
Tested by: slavash (Mellanox)
Reviewed by: markj (no formal review but caught my unlock mistake)
Approved by: re (kib)
not freed. This can happen since the list traversal and locking
was converted to epoch(9). If the inp is marked "freed", skip it.
This prevents a NULL pointer deref panic in ip6_savecontrol_v4()
trying to access the socket hanging off the inp, which was gone
by the time we got there.
Reported by: andrew
Tested by: andrew
Approved by: re (gjb)
route cache updates.
Bring over locking changes applied to udp_output() for the route cache
in r297225 and fixed in r306559 which achieve multiple things:
(1) acquire an exclusive inp lock earlier depending on the expected
conditions; we add a comment explaining this in udp6,
(2) having acquired the exclusive lock earlier eliminates a slight
possible chance for a race condition which was present in v4 for
multiple years as well and is now gone, and
(3) only pass the inp_route6 to ip6_output() if we are holding an
exclusive inp lock, so that possible route cache updates in case
of routing table generation number changes can happen safely.
In addition this change (as the legacy IP counterpart) decomposes the
tracking of inp and pcbinfo lock and adds extra assertions, that the
two together are acquired correctly.
PR: 230950
Reviewed by: karels, markj
Approved by: re (gjb)
Pointyhat to: bz (for completely missing this bit)
Differential Revision: https://reviews.freebsd.org/D17230
Lookups are protected by an epoch section, so the LB group linkage must
be a CK_LIST rather than a plain LIST. Furthermore, we were not
deferring LB group frees, so in_pcbremlbgrouphash() could race with
readers and cause a use-after-free.
Reviewed by: sbruno, Johannes Lundberg <johalun0@gmail.com>
Tested by: gallatin
Approved by: re (gjb)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17031
to clear L2 and L3 route caches.
Also mark one function argument as __unused.
Reviewed by: karels, ae
Approved by: re (rgrimes)
Differential Revision: https://reviews.freebsd.org/D17007
macro rather than hand crafted code.
No functional changes.
Reviewed by: karels
Approved by: re (rgrimes)
Differential Revision: https://reviews.freebsd.org/D17006
inp_route6 for IPv6 code after r301217.
This was most likely a c&p error from the legacy IP code, which
did not matter as it is a union and both structures have the same
layout at the beginning.
No functional changes.
Reviewed by: karels, ae
Approved by: re (rgrimes)
Differential Revision: https://reviews.freebsd.org/D17005
r337776 started hashing the fragments into buckets for faster lookup.
The hashkey is larger than intended. This results in random stack data being
included in the hashed data, which in turn means that fragments of the same
packet might end up in different buckets, causing the reassembly to fail.
Set the correct size for hashkey.
PR: 231045
Approved by: re (kib)
MFC after: 3 days
Similar to how the IPv4 code will reject an IPv6 LB group,
we must ignore IPv4 LB groups when looking up an IPv6
listening socket. If this is not done, a port only match
may return an IPv4 socket, which causes problems (like
sending IPv6 packets with a hopcount of 0, making them unrouteable).
Thanks to rrs for all the work to diagnose this.
Approved by: re (rgrimes)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D16899
Migrate udp6_send() v4mapped code to udp6_output() saving us a re-lock and
further simplifying the address-family handling code by eliminating
AF_INET checks and almost all v4mapped handling right after the start
as cases could actually not happen anymore.
Rework output path locking similar to UDP4 allowing for better
parallelism (see r222488, and later versions).
Sponsored by: The FreeBSD Foundation (2012)
Sponsored by: iXsystems (2012)
Differential Revision: https://reviews.freebsd.org/D3721
This is actually several different bugs:
- The code is not designed to handle inpcb deletion after interface deletion
- add reference for inpcb membership
- The multicast address has to be removed from interface lists when the refcount
goes to zero OR when the interface goes away
- decouple list disconnect from refcount (v6 only for now)
- ifmultiaddr can exist past being on interface lists
- add flag for tracking whether or not it's enqueued
- deferring freeing moptions makes the incpb cleanup code simpler but opens the
door wider still to races
- call inp_gcmoptions synchronously after dropping the the inpcb lock
Fundamentally multicast needs a rewrite - but keep applying band-aids for now.
Tested by: kp
Reported by: novel, kp, lwhsu
Currently, the limits are quite high. On machines with millions of
mbuf clusters, the reassembly queue limits can also run into
the millions. Lower these values.
Also, try to ensure that no bucket will have a reassembly
queue larger than approximately 100 items. This limits the cost to
find the correct reassembly queue when processing an incoming
fragment.
Due to the low limits on each bucket's length, increase the size of
the hash table from 64 to 1024.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
Currently, we process IPv6 fragments with 0 bytes of payload, add them
to the reassembly queue, and do not recognize them as duplicating or
overlapping with adjacent 0-byte fragments. An attacker can exploit this
to create long fragment queues.
There is no legitimate reason for a fragment with no payload. However,
because IPv6 packets with an empty payload are acceptable, allow an
"atomic" fragment with no payload.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
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
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
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
Currently, all IPv6 fragment reassembly queues are kept in a flat
linked list. This has a number of implications. Two significant
implications are: all reassembly operations share a common lock,
and it is possible for the linked list to grow quite large.
Improve IPv6 reassembly performance by hashing fragments into buckets,
each of which has its own lock. Calculate the hash key using a Jenkins
hash with a random seed.
Reviewed by: jhb
Security: FreeBSD-SA-18:10.ip
Security: CVE-2018-6923
It was lost when tryforward appeared. Now ip[6]_tryforward will be enabled
only when sending redirects for corresponding IP version is disabled via
sysctl. Otherwise will be used default forwarding function.
PR: 221137
Submitted by: mckay@
MFC after: 2 weeks
On PowerPC (and possibly other architectures), that doesn't use
EARLY_AP_STARTUP, the config task queue may be used initialized.
This was observed while trying to mount the root fs from NFS, as
reported here: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=230168.
This patch has 2 main changes:
1- Perform a basic initialization of qgroup_config, similar to
what is done in taskqgroup_adjust, but simpler.
This makes qgroup_config ready to be used during NFS root mount.
2- When EARLY_AP_STARTUP is not used, call inm_init() and
in6m_init() right before SI_SUB_ROOT_CONF, because bootp needs
to send multicast packages to request an IP.
PR: Bug 230168
Reported by: sbruno
Reviewed by: jhibbits, mmacy, sbruno
Approved by: jhibbits
Differential Revision: D16633
The dtrace provider for UDP-Lite is modeled after the UDP provider.
This fixes the bug that UDP-Lite packets were triggering the UDP
provider.
Thanks to dteske@ for providing the dwatch module.
Reviewed by: dteske@, markj@, rrs@
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D16377
TCP/IPv4 allows an implicit connection setup using sendto(), which
is used for TTCP and TCP fast open. This patch adds support for
TCP/IPv6.
While there, improve some tests for detecting multicast addresses,
which are mapped.
Reviewed by: bz@, kbowling@, rrs@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16458
The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have grown at least 28 syscalls that use timespecs in some
way, leading many programs both inside and outside of the base system to
redefine those macros. It's better just to make the definitions public.
Our kernel currently defines two-argument versions of timespecadd and
timespecsub. NetBSD, OpenBSD, and FreeDesktop.org's libbsd, however, define
three-argument versions. Solaris also defines a three-argument version, but
only in its kernel. This revision changes our definition to match the
common three-argument version.
Bump _FreeBSD_version due to the breaking KPI change.
Discussed with: cem, jilles, ian, bde
Differential Revision: https://reviews.freebsd.org/D14725
Fire UDP receive probes when a packet is received and there is no
endpoint consuming it. Fire the probe also if the TTL of the
received packet is smaller than the minimum required by the endpoint.
Clarify also in the man page, when the probe fires.
Reviewed by: dteske@, markj@, rrs@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16046
This deduplicates the code a bit, and also implicitly adds missing
callout_stop() to in[6]_lltable_delete_entry() functions.
PR: 209682, 225927
Submitted by: hselasky (previous version)
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D4605
Simple fix to address panics relating to setting IPV6_TCLASS
with setsockopt(). The premise of this change is that it is
ok to call malloc with M_NOWAIT while holding a lock on the
in6p.
If it later turns out that it is not ok, then major surgery
will be required, as ip6_setpktopt() will have to be fixed
(as it also calls malloc with M_NOWAIT) which pulls in the
ip6_pcbopts(), ip6_setpktopts(), ip6_setpktopt() call chain.
Submitted by: Jason Eggnet
Reviewed by: rrs, transport, sbruno
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D16201
- Add tracker argument to preemptible epochs
- Inline epoch read path in kernel and tied modules
- Change in_epoch to take an epoch as argument
- Simplify tfb_tcp_do_segment to not take a ti_locked argument,
there's no longer any benefit to dropping the pcbinfo lock
and trying to do so just adds an error prone branchfest to
these functions
- Remove cases of same function recursion on the epoch as
recursing is no longer free.
- Remove the the TAILQ_ENTRY and epoch_section from struct
thread as the tracker field is now stack or heap allocated
as appropriate.
Tested by: pho and Limelight Networks
Reviewed by: kbowling at llnw dot com
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D16066
encap_lookup_t method can be invoked by IP encap subsytem even if none
of gif/gre/me interfaces are exist. Hash tables are allocated on demand,
when first interface is created. So, make NULL pointer check before
doing access to hash table.
PR: 229378
Using of rwlock with multiqueue NICs for IP forwarding on high pps
produces high lock contention and inefficient. Rmlock fits better for
such workloads.
Reviewed by: melifaro, olivier
Obtained from: Yandex LLC
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D15789
It is possible that ifma_protospec becomes NULL in this function for
some entry, but it is still referenced and thus it will not unlinked
from the list. Then "restart" condition triggers and this entry with
NULL ifma_protospec will lead to page fault.
PR: 228982
of needed interface when many gre interfaces are present.
Remove rmlock from gre_softc, use epoch(9) and CK_LIST instead.
Move more AF-related code into AF-related locations. Use hash table to
speedup lookup of needed softc.
This patch adds a new socket option, SO_REUSEPORT_LB, which allow multiple
programs or threads to bind to the same port and incoming connections will be
load balanced using a hash function.
Most of the code was copied from a similar patch for DragonflyBSD.
However, in DragonflyBSD, load balancing is a global on/off setting and can not
be set per socket. This patch allows for simultaneous use of both the current
SO_REUSEPORT and the new SO_REUSEPORT_LB options on the same system.
Required changes to structures:
Globally change so_options from 16 to 32 bit value to allow for more options.
Add hashtable in pcbinfo to hold all SO_REUSEPORT_LB sockets.
Limitations:
As DragonflyBSD, a load balance group is limited to 256 pcbs (256 programs or
threads sharing the same socket).
This is a substantially different contribution as compared to its original
incarnation at svn r332894 and reverted at svn r332967. Thanks to rwatson@
for the substantive feedback that is included in this commit.
Submitted by: Johannes Lundberg <johalun0@gmail.com>
Obtained from: DragonflyBSD
Relnotes: Yes
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D11003
of needed interface when many gif interfaces are present.
Remove rmlock from gif_softc, use epoch(9) and CK_LIST instead.
Move more AF-related code into AF-related locations.
Use hash table to speedup lookup of needed softc. Interfaces
with GIF_IGNORE_SOURCE flag are stored in plain CK_LIST.
Sysctl net.link.gif.parallel_tunnels is removed. The removal was planed
16 years ago, and actually it could work only for outbound direction.
Each protocol, that can be handled by if_gif(4) interface is registered
by separate encap handler, this helps avoid invoking the handler
for unrelated protocols (GRE, PIM, etc.).
This change allows dramatically improve performance when many gif(4)
interfaces are used.
Sponsored by: Yandex LLC
Currently it has several disadvantages:
- it uses single mutex to protect internal structures. It is used by
data- and control- path, thus there are no parallelism at all.
- it uses single list to keep encap handlers for both INET and INET6
families.
- struct encaptab keeps unneeded information (src, dst, masks, protosw),
that isn't used by code in the source tree.
- matches are prioritized and when many tunneling interfaces are
registered, encapcheck handler of each interface is invoked for each
packet. The search takes O(n) for n interfaces. All this work is done
with exclusive lock held.
What this patch includes:
- the datapath is converted to be lockless using epoch(9) KPI.
- struct encaptab now linked using CK_LIST.
- all unused fields removed from struct encaptab. Several new fields
addedr: min_length is the minimum packet length, that encapsulation
handler expects to see; exact_match is maximum number of bits, that
can return an encapsulation handler, when it wants to consume a packet.
- IPv6 and IPv4 handlers are stored in separate lists;
- added new "encap_lookup_t" method, that will be used later. It is
targeted to speedup lookup of needed interface, when gif(4)/gre(4) have
many interfaces.
- the need to use protosw structure is eliminated. The only pr_input
method was used from this structure, so I don't see the need to keep
using it.
- encap_input_t method changed to avoid using mbuf tags to store softc
pointer. Now it is passed directly trough encap_input_t method.
encap_getarg() funtions is removed.
- all sockaddr structures and code that uses them removed. We don't have
any code in the tree that uses them. All consumers use encap_attach_func()
method, that relies on invoking of encapcheck() to determine the needed
handler.
- introduced struct encap_config, it contains parameters of encap handler
that is going to be registered by encap_attach() function.
- encap handlers are stored in lists ordered by exact_match value, thus
handlers that need more bits to match will be checked first, and if
encapcheck method returns exact_match value, the search will be stopped.
- all current consumers changed to use new KPI.
Reviewed by: mmacy
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D15617
Per vnet(9), CURVNET_SET and CURVNET_RESTORE cannot be used as a single
statement for a conditional and CURVNET_RESTORE must be in the same
block as CURVNET_SET (or a subblock).
Reviewed by: andrew
Sponsored by: The FreeBSD Foundation
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)
r333175 updated the join_group functions, but not the leave_group ones.
Reviewed by: sbruno
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D15393
Use LIST_FOREACH_SAFE in in6m_disconnect() since we're
deleting and freeing item from the membership list
while traversing the list.
Reviewed by: mmacy
Sponsored by: Netflix
based link-local address.
The default link local address for IPv6 is added as part of bringing the
network interface up. Move the call to "EVENTHANDLER_INVOKE(ifaddr_event,)"
from the SIOCAIFADDR_IN6 ioctl(2) handler to in6_notify_ifa() which should
catch all the cases of adding IPv6 based addresses to a network interface.
Add a witness warning in case the event handler is not allowed to sleep.
Reviewed by: network (ae), kib
Differential Revision: https://reviews.freebsd.org/D13407
MFC after: 1 week
Sponsored by: Mellanox Technologies
to sleep on commands to the NIC when updating multicast filters. More generally this permitted
driver's to use an sx as a softc lock. Unfortunately this change introduced a race whereby a
a multicast update would still be queued for deletion when ifconfig deleted the interface
thus calling down in to _purgemaddrs and synchronously deleting _all_ of the multicast addresses
on the interface.
Synchronously remove all external references to a multicast address before enqueueing for delete.
Reported by: lwhsu
Approved by: sbruno
to avoid a LOR on the multicast list lock in the freemoptions routines.
As it turns out, tcp_usr_detach can acquire the tcbinfo lock readonly.
Trying to wunlock the pcbinfo lock in that context has caused a number
of reported crashes.
This change unclutters in_pcbfree and moves the handling of wunlock vs
runlock of pcbinfo to the freemoptions routine.
Reported by: mjg@, bde@, o.hartmann at walstatt.org
Approved by: sbruno
is too big for the outgoing interface and no firewall is involed.
This problem was introduced in
https://svnweb.freebsd.org/changeset/base/324996
Thanks to Irene Ruengeler for finding the bug and testing the fix.
Reviewed by: kp@
MFC after: 3 days
Multicast incorrectly calls in to drivers with a mutex held causing drivers
to have to go through all manner of contortions to use a non sleepable lock.
Serialize multicast updates instead.
Submitted by: mmacy <mmacy@mattmacy.io>
Reviewed by: shurd, sbruno
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14969
This patch adds a new socket option, SO_REUSEPORT_LB, which allow multiple
programs or threads to bind to the same port and incoming connections will be
load balanced using a hash function.
Most of the code was copied from a similar patch for DragonflyBSD.
However, in DragonflyBSD, load balancing is a global on/off setting and can not
be set per socket. This patch allows for simultaneous use of both the current
SO_REUSEPORT and the new SO_REUSEPORT_LB options on the same system.
Required changes to structures
Globally change so_options from 16 to 32 bit value to allow for more options.
Add hashtable in pcbinfo to hold all SO_REUSEPORT_LB sockets.
Limitations
As DragonflyBSD, a load balance group is limited to 256 pcbs
(256 programs or threads sharing the same socket).
Submitted by: Johannes Lundberg <johanlun0@gmail.com>
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D11003
considered as originated by our host packet. And thus rcvif should be
NULL, since it is used by ipfw(4) to determine that packet was originated
from this host. Some of icmp6_reflect() consumers reuse mbuf and m_pkthdr
without resetting rcvif pointer. To avoid this always reset m_pkthdr.rcvif
pointer to NULL in icmp6_reflect(). Also remove such line and comment
describing this from icmp6_error(), since it does not longer matters.
PR: 227674
Reported by: eugen
MFC after: 1 week
While Arcnet has some continued deployment in industrial controls, the
lack of drivers for any of the PCI, USB, or PCIe NICs on the market
suggests such users aren't running FreeBSD.
Evidence in the PR database suggests that the cm(4) driver (our sole
Arcnet NIC) was broken in 5.0 and has not worked since.
PR: 182297
Reviewed by: jhibbits, vangyzen
Relnotes: yes
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D15057
Defines in net/if_media.h remain in case code copied from ifconfig is in
use elsewere (supporting non-existant media type is harmless).
Reviewed by: kib, jhb
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D15017
opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.
Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c. A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.
Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.
Reviewed by: kib, cem, jhb, jtl
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14941
- The two types must be type-punnable for shared members of ifr_ifru.
This allows compatibility accessors to be shared.
- There must be no padding gap between ifr_name and ifr_ifru. This is
assumed in tcpdump's use of SIOCGIFFLAGS output which attempts to be
broadly portable. This is true for all current architectures, but very
large (256-bit) fat-pointers could violate this invariant.
Reviewed by: kib
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14910
currently on the queue. This prevents accidentally doubly-removing a DAD
entry from the queue, while also simplifying some of the logic in
nd6_dad_stop().
Reviewed by: ae, hrs, vangyzen
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D10943
Forwarded packets passed through PFIL_OUT, which made it difficult for
firewalls to figure out if they were forwarding or producing packets. This in
turn is an issue for pf for IPv6 fragment handling: it needs to call
ip6_output() or ip6_forward() to handle the fragments. Figuring out which was
difficult (and until now, incorrect).
Having pfil distinguish the two removes an ugly piece of code from pf.
Introduce a new variant of the netpfil callbacks with a flags variable, which
has PFIL_FWD set for forwarded packets. This allows pf to reliably work out if
a packet is forwarded.
Reviewed by: ae, kevans
Differential Revision: https://reviews.freebsd.org/D13715
Created GET_PKTOPT_EXT_HDR() and GET_PKTOPT_SOCKADDR() macros to
handle safely fetching options from in6p_outputopts, including
properly dealing with in6p locking and preparing memory for
sooptcopyout().
Changed the function signature of ip6_getpcbopt() to allow the
function to acquire and release locks on in6p as needed.
Submitted by: Jason Eggleston <jason@eggnet.com>
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14619
through the lock-switching hoops.
A few of the INP lookup operations that lock INPs after the lookup do
so using this mechanism (to maintain lock ordering):
1. Lock lookup structure.
2. Find INP.
3. Acquire reference on INP.
4. Drop lock on lookup structure.
5. Acquire INP lock.
6. Drop reference on INP.
This change provides a slightly shorter path for cases where the INP
lock is uncontested:
1. Lock lookup structure.
2. Find INP.
3. Try to acquire the INP lock.
4. If successful, drop lock on lookup structure.
Of course, if the INP lock is contested, the functions will need to
revert to the previous way of switching locks safely.
This saves a few atomic operations when the INP lock is uncontested.
Discussed with: gallatin, rrs, rwatson
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D12911
Current arp/nd code relies on the feedback from the datapath indicating
that the entry is still used. This mechanism is incorporated into the
arpresolve()/nd6_resolve() routines. After the inpcb route cache
introduction, the packet path for the locally-originated packets changed,
passing cached lle pointer to the ether_output() directly. This resulted
in the arp/ndp entry expire each time exactly after the configured max_age
interval. During the small window between the ARP/NDP request and reply
from the router, most of the packets got lost.
Fix this behaviour by plugging datapath notification code to the packet
path used by route cache. Unify the notification code by using single
inlined function with the per-AF callbacks.
Reported by: sthaug at nethelp.no
Reviewed by: ae
MFC after: 2 weeks
ip6_calcmtu() only looks at the interface MTU if neither the TCP hostcache
nor the route provides an MTU. Update the routes so they do not provide
stale MTUs.
This fixes UNH IPv6 conformance test cases v6LC_4_1_08 and v6LC_4_1_09,
which use a RA to reduce the link MTU from 1500 to 1280.
Reported and tested by: Farrell Woods <Farrell_Woods@Dell.com>
Reviewed by: dab, melifaro
Discussed with: ae
MFC after: 1 week
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D14257
icmp6_redirect_input() validates that a redirect packet came from the
current gateway for the respective destination. To do this, it compares
the source address, which has an embedded scope zone id, to the next-hop
address, which does not. If the address is link-local, which should be
the case, the comparison fails and the redirect is ignored.
Insert the scope zone id into the next-hop address so the comparison
is accurate.
Unsurprisingly, this fixes 35 UNH IPv6 conformance test cases.
Submitted by: Farrell Woods <Farrell_Woods@Dell.com> (initial revision)
Reviewed by: ae melifaro dab
MFC after: 1 week
Relnotes: yes
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D14254
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
Fix a pretty simple, yet pretty tragic typo: we should return IPPROTO_DONE,
not IPPROTO_NONE. With IPPROTO_NONE we will keep parsing the header chain
on an mbuf that was already freed.
Reported by: Maxime Villard <max at m00nbsd dot net>
MFC after: 3 days
Restore state 6. Many of the UNH tests end up exercising this
state, where we have a new neighbor cache entry and a new link-layer
entry is being created for it. The link-layer address is currently
unknown so the initial state of the "llentry" should remain initialized
to ND6_LLINFO_NOSTATE so that the ND code will send a solicitation.
Setting this to ND6_LLINFO_STALE implies that the link-level entry
is valid and can be used (but needs to be refreshed via the Neighbor
Unreachability state machine).
https://forums.freebsd.org/threads/64287/
Submitted by: Farrell Woods <Farrell_Woods@Dell.com>
Reviewed by: mjoras, dab, ae
MFC after: 1 week
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D14059
When mbuf has M_FASTFWD_OURS flag, this means that a destination address
is our local, but we still need to pass scope zone violation check,
because protocol level expects that IPv6 link-local addresses have
embedded scope zone indexes. This should fix the problem, when ipfw is
used to forward packets to local address and source address of a packet
is IPv6 LLA.
Reported by: sbruno
MFC after: 3 weeks
When an interface has IFF_LOOPBACK flag in6_ifattach() tries to assing
IPv6 loopback address to this interface. It uses in6ifa_ifpwithaddr()
to check, that interface doesn't already have given address and then
uses in6_ifattach_loopback(). If in6_ifattach_loopback() fails, it just
exits and thus skips assignment of IPv6 LLA.
Fix this using in6ifa_ifwithaddr() function. If IPv6 loopback address is
already assigned in the system, do not call in6_ifattach_loopback().
PR: 138678
MFC after: 3 weeks
the first mbuf of the reassembled datagram should have a pkthdr.
This was discovered with cxgbe(4) + IPSEC + ping with payload more than
interface MTU. cxgbe can generate !M_WRITEABLE mbufs and this results
in m_unshare being called on the reassembled datagram, and it complains:
panic: m_unshare: m0 0xfffff80020f82600, m 0xfffff8005d054100 has M_PKTHDR
PR: 224922
Reviewed by: ae@
MFC after: 1 week
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D14009
Uses of mallocarray(9).
The use of mallocarray(9) has rocketed the required swap to build FreeBSD.
This is likely caused by the allocation size attributes which put extra pressure
on the compiler.
Given that most of these checks are superfluous we have to choose better
where to use mallocarray(9). We still have more uses of mallocarray(9) but
hopefully this is enough to bring swap usage to a reasonable level.
Reported by: wosch
PR: 225197
Focus on code where we are doing multiplications within malloc(9). None of
these ire likely to overflow, however the change is still useful as some
static checkers can benefit from the allocation attributes we use for
mallocarray.
This initial sweep only covers malloc(9) calls with M_NOWAIT. No good
reason but I started doing the changes before r327796 and at that time it
was convenient to make sure the sorrounding code could handle NULL values.
X-Differential revision: https://reviews.freebsd.org/D13837
This bring back r327293 from OpenBSD, with the important difference that
we are now getting it from their ip6_id.c file.
Obtained from: OpenBSD (CVS v1.3)
correct non-repetitive ID code, based on comments from niels provos.
- seed2 is necessary, but use it as "seed2 + x" not "seed2 ^ x".
- skipping number is not needed, so disable it for 16bit generator (makes
the repetition period to 30000)
Obtained from: OpenBSD (CVS rev. 1.2)
MFC after: 1 week
netinet6/ip6_id.c: niels kindly dropped clause 3/4 from the license.
I was looking at the wrong file. There is an important merge that must be
done before I can bring this change.
This file is supposed to be based on the OpenBSD CVS v1.6 but checking
the OpenBSD repository the license had already dropped the 2&3 clasues by
then. Catch up with the licensing.
Obtained from: OpenBSD (CVS 1.2)
This reduces noise when kernel is compiled by newer GCC versions,
such as one used by external toolchain ports.
Reviewed by: kib, andrew(sys/arm and sys/arm64), emaste(partial), erj(partial)
Reviewed by: jhb (sys/dev/pci/* sys/kern/vfs_aio.c and sys/kern/kern_synch.c)
Differential Revision: https://reviews.freebsd.org/D10385
clang does not know that two lookup calls will return the same
pointer, so it assumes correctly that using the old pointer
after dropping the reference to it is a bit risky.
that had the IPv6 fragmentation header:
o Neighbor Solicitation
o Neighbor Advertisement
o Router Solicitation
o Router Advertisement
o Redirect
Introduce M_FRAGMENTED mbuf flag, and set it after IPv6 fragment reassembly
is completed. Then check the presence of this flag in correspondig ND6
handling routines.
PR: 224247
MFC after: 2 weeks
This option was used in the early days to allow performance measurements
extrapolating the use of SCTP checksum offloading. Since this feature
is now available, get rid of this option.
This also un-breaks the LINT kernel. Thanks to markj@ for making me
aware of the problem.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
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.
No functional change intended.
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.
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.
Initially, only tag files that use BSD 4-Clause "Original" license.
RelNotes: yes
Differential Revision: https://reviews.freebsd.org/D13133
and other similar socket options.
Provide new control message SCM_TIME_INFO to supply information about
timestamp. Currently it indicates that the timestamp was
hardware-assisted and high-precision, for software timestamps the
message is not returned. Reserved fields are added to ABI to report
additional info about it, it is expected that raw hardware clock value
might be useful for some applications.
Reviewed by: gallatin (previous version), hselasky
Sponsored by: Mellanox Technologies
MFC after: 2 weeks
X-Differential revision: https://reviews.freebsd.org/D12638
Defer the packet size check until after the firewall has had a look at it. This
means that the firewall now has the opportunity to (re-)fragment an oversized
packet.
This mirrors what the slow path does.
Reviewed by: ae
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D12779
Violators may define _WANT_SOCKET and _WANT_UNPCB respectively and
are not guaranteed for stability of the structures. The violators
list is the the usual one: libprocstat(3) and netstat(1) internally
and lsof in ports.
In struct xunpcb remove the inclusion of kernel structure and add
a bunch of spare fields. The xsocket already has socket not included,
but add there spares as well. Embed xsockbuf into xsocket.
Sort declarations in sys/socketvar.h to separate kernel only from
userland available ones.
PR: 221820 (exp-run)
flowtable anymore (as flowtable was never considered to be useful in
the forwarding path).
Reviewed by: np
Differential Revision: https://reviews.freebsd.org/D11448
This macro allocates memory and, if malloc does not return NULL, copies
data into the new memory. However, it doesn't just check whether malloc
returns NULL. It also checks whether we called malloc with M_NOWAIT. That
is not necessary.
While it may be that malloc() will only return NULL when the M_NOWAIT flag
is set, we don't need to check for this when checking malloc's return
value. Further, in this case, the check was not completely accurate,
because it checked for flags == M_NOWAIT, rather than treating it as a bit
field and checking for (flags & M_NOWAIT).
Reviewed by: ae
MFC after: 2 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D10942
in the icmp6_input() function.
When processing an ICMP6_ECHO_REQUEST, if IP6_EXTHDR_GET fails, it will
set nicmp6 and n to NULL. Therefore, we should condition our modification
to nicmp6 on n being not NULL.
And, when processing an ICMP6_WRUREQUEST in the (mode != FQDN) case, if
m_dup_pkthdr() fails, the code will set n to NULL. However, the very next
line dereferences n. Therefore, when m_dup_pkthdr() fails, we should
discontinue further processing and follow the same path as when m_gethdr()
fails.
Reported by: clang static analyzer
Reviewed by: ae
MFC after: 2 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D10941
response.
Delete an unneeded rate limit for UDP under IPv6. Because ICMP6
messages have their own rate limit, it is unnecessary to apply a
second rate limit to UDP messages.
Reviewed by: glebius
MFC after: 2 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D10387
if it is called on a TCP socket
* with an IPv6 address and the socket is bound to an
IPv4-mapped IPv6 address.
* with an IPv4-mapped IPv6 address and the socket is bound to an
IPv6 address.
Thanks to Jonathan T. Leighton for reporting this issue.
Reviewed by: bz gnn
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D9163
A long long time ago the register keyword told the compiler to store
the corresponding variable in a CPU register, but it is not relevant
for any compiler used in the FreeBSD world today.
ANSIfy related prototypes while here.
Reviewed by: cem, jhb
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D10193
compiled into the kernel
This ensures that .iss_asm (the number of ASM listeners) isn't incorrectly
decremented for MLD-layer source datagrams when inspecting im*s_st[1]
(the second state in the structure).
MFC after: 2 months
PR: 217509 [1]
Reported by: Coverity (Isilon)
Reviewed by: ae ("This patch looks correct to me." [1])
Submitted by: Miles Ohlrich <miles.ohlrich@isilon.com>
Sponsored by: Dell EMC Isilon
Rename the mtu variable in ip6_fragment(), because mtu is misleading. The
variable actually holds the fragment length.
No functional change.
Suggested by: ae
When forwarding pf tracks the size of the largest fragment in a fragmented
packet, and refragments based on this size.
It failed to ensure that this size was a multiple of 8 (as is required for all
but the last fragment), so it could end up generating incorrect fragments.
For example, if we received an 8 byte and 12 byte fragment pf would emit a first
fragment with 12 bytes of payload and the final fragment would claim to be at
offset 8 (not 12).
We now assert that the fragment size is a multiple of 8 in ip6_fragment(), so
other users won't make the same mistake.
Reported by: Antonios Atlasis <aatlasis at secfu net>
MFC after: 3 days
do for streaming sockets.
And do more cleanup in the sbappendaddr_locked_internal() to prevent
leak information from existing mbuf to the one, that will be possible
created later by netgraph.
Suggested by: glebius
Tested by: Irina Liakh <spell at itl ua>
MFC after: 1 week
When checksums of received IP and UDP header already checked, UDP uses
sbappendaddr_locked() to pass received data to the socket.
sbappendaddr_locked() uses given mbuf as is, and if NIC supports checksum
offloading, mbuf contains csum_data and csum_flags that were calculated
for already stripped headers. Some NICs support only limited checksums
offloading and do not use CSUM_PSEUDO_HDR flag, and csum_data contains
some value that UDP/TCP should use for pseudo header checksum calculation.
When L2TP is used for tunneling with mpd5, ng_ksocket receives mbuf with
filled csum_flags and csum_data, that were calculated for outer headers.
When L2TP header is stripped, a packet that was tunneled goes to the IP
layer and due to presence of csum_flags (without CSUM_PSEUDO_HDR) and
csum_data, the UDP/TCP checksum check fails for this packet.
Reported by: Irina Liakh <spell at itl ua>
Tested by: Irina Liakh <spell at itl ua>
MFC after: 1 week
If a jail has an explicitly assigned IPv6 loopback address then allow it
to be used instead of remapping requests for the loopback adddress to the
first IPv6 address assigned to the jail.
This fixes issues where applications attempt to detect their bound port
where they requested a loopback address, which was available, but instead
the kernel remapped it to the jails first address.
This is the same fix applied to IPv4 fix by: r316313
Also:
* Correct the description of prison_check_ip6_locked to match the code.
MFC after: 2 weeks
Relnotes: Yes
Sponsored by: Multiplay
ip_forward, TCP/IPv6, and probably SCTP leaked references to L2 cache
entry because they used their own routes on the stack, not in_pcb routes.
The original model for route caching was callers that provided a route
structure to ip{,6}input() would keep the route, and this model was used
for L2 caching as well. Instead, change L2 caching to be done by default
only when using a route structure in the in_pcb; the pcb deallocation
code frees L2 as well as L3 cacches. A separate change will add route
caching to TCP/IPv6.
Another suggestion was to have the transport protocols indicate willingness
to use L2 caching, but this approach keeps the changes in the network
level
Reviewed by: ae gnn
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D10059
sys/netinet6/icmp6.c
Use the interface's FIB for source address selection in ICMPv6 error
responses.
sys/netinet6/in6.c
In in6_newaddrmsg, announce arrival of local addresses on the
interface's FIB only. In in6_lltable_rtcheck, use a per-fib ND6
cache instead of a single cache.
sys/netinet6/in6_src.c
In in6_selectsrc, use the caller's fib instead of the default fib.
In in6_selectsrc_socket, remove a superfluous check.
sys/netinet6/nd6.c
In nd6_lle_event, use the interface's fib for routing socket
messages. In nd6_is_new_addr_neighbor, check all FIBs when trying
to determine whether an address is a neighbor. Also, simplify the
code for point to point interfaces.
sys/netinet6/nd6.h
sys/netinet6/nd6.c
sys/netinet6/nd6_rtr.c
Make defrouter_select fib-aware, and make all of its callers pass in
the interface fib.
sys/netinet6/nd6_nbr.c
When inputting a Neighbor Solicitation packet, consider the
interface fib instead of the default fib for DAD. Output NS and
Neighbor Advertisement packets on the correct fib.
sys/netinet6/nd6_rtr.c
Allow installing the same host route on different interfaces in
different FIBs. If rt_add_addr_allfibs=0, only install or delete
the prefix route on the interface fib.
tests/sys/netinet/fibs_test.sh
Clear some expected failures, but add a skip for the newly revealed
BUG217871.
PR: 196361
Submitted by: Erick Turnquist <jhujhiti@adjectivism.org>
Reported by: Jason Healy <jhealy@logn.net>
Reviewed by: asomers
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D9451
Unfortunately they will have different integer value due to Linux value being already assigned in FreeBSD.
The patch is similar to IP_RECVDSTADDR but also provides the destination port value to the application.
This allows/improves implementation of transparent proxies on UDP sockets due to having the whole information on forwarded packets.
Reviewed by: adrian, aw
Approved by: ae (mentor)
Sponsored by: rsync.net
Differential Revision: D9235
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
and csum_flags using information from all fragments. This fixes
dropping of reassembled packets due to wrong checksum when the IPv6
checksum offloading is enabled on a network card.
Obtained from: Yandex LLC
MFC after: 1 week
Sponsored by: Yandex LLC
The inpcb structure has inp_sp pointer that is initialized by
ipsec_init_pcbpolicy() function. This pointer keeps strorage for IPsec
security policies associated with a specific socket.
An application can use IP_IPSEC_POLICY and IPV6_IPSEC_POLICY socket
options to configure these security policies. Then ip[6]_output()
uses inpcb pointer to specify that an outgoing packet is associated
with some socket. And IPSEC_OUTPUT() method can use a security policy
stored in the inp_sp. For inbound packet the protocol-specific input
routine uses IPSEC_CHECK_POLICY() method to check that a packet conforms
to inbound security policy configured in the inpcb.
SCTP protocol doesn't specify inpcb for ip[6]_output() when it sends
packets. Thus IPSEC_OUTPUT() method does not consider such packets as
associated with some socket and can not apply security policies
from inpcb, even if they are configured. Since IPSEC_CHECK_POLICY()
method is called from protocol-specific input routine, it can specify
inpcb pointer and associated with socket inbound policy will be
checked. But there are two problems:
1. Such check is asymmetric, becasue we can not apply security policy
from inpcb for outgoing packet.
2. IPSEC_CHECK_POLICY() expects that caller holds INPCB lock and
access to inp_sp is protected. But for SCTP this is not correct,
becasue SCTP uses own locks to protect inpcb.
To fix these problems remove IPsec related PCB code from SCTP.
This imply that IP_IPSEC_POLICY and IPV6_IPSEC_POLICY socket options
will be not applicable to SCTP sockets. To be able correctly check
inbound security policies for SCTP, mark its protocol header with
the PR_LASTHDR flag.
Reported by: tuexen
Reviewed by: tuexen
Differential Revision: https://reviews.freebsd.org/D9538
Unfortunately they will have different integer value due to Linux value being already assigned in FreeBSD.
The patch is similar to IP_RECVDSTADDR but also provides the destination port value to the application.
This allows/improves implementation of transparent proxies on UDP sockets due to having the whole information on forwarded packets.
Sponsored-by: rsync.net
Differential Revision: D9235
Reviewed-by: adrian
Small summary
-------------
o Almost all IPsec releated code was moved into sys/netipsec.
o New kernel modules added: ipsec.ko and tcpmd5.ko. New kernel
option IPSEC_SUPPORT added. It enables support for loading
and unloading of ipsec.ko and tcpmd5.ko kernel modules.
o IPSEC_NAT_T option was removed. Now NAT-T support is enabled by
default. The UDP_ENCAP_ESPINUDP_NON_IKE encapsulation type
support was removed. Added TCP/UDP checksum handling for
inbound packets that were decapsulated by transport mode SAs.
setkey(8) modified to show run-time NAT-T configuration of SA.
o New network pseudo interface if_ipsec(4) added. For now it is
build as part of ipsec.ko module (or with IPSEC kernel).
It implements IPsec virtual tunnels to create route-based VPNs.
o The network stack now invokes IPsec functions using special
methods. The only one header file <netipsec/ipsec_support.h>
should be included to declare all the needed things to work
with IPsec.
o All IPsec protocols handlers (ESP/AH/IPCOMP protosw) were removed.
Now these protocols are handled directly via IPsec methods.
o TCP_SIGNATURE support was reworked to be more close to RFC.
o PF_KEY SADB was reworked:
- now all security associations stored in the single SPI namespace,
and all SAs MUST have unique SPI.
- several hash tables added to speed up lookups in SADB.
- SADB now uses rmlock to protect access, and concurrent threads
can do SA lookups in the same time.
- many PF_KEY message handlers were reworked to reflect changes
in SADB.
- SADB_UPDATE message was extended to support new PF_KEY headers:
SADB_X_EXT_NEW_ADDRESS_SRC and SADB_X_EXT_NEW_ADDRESS_DST. They
can be used by IKE daemon to change SA addresses.
o ipsecrequest and secpolicy structures were cardinally changed to
avoid locking protection for ipsecrequest. Now we support
only limited number (4) of bundled SAs, but they are supported
for both INET and INET6.
o INPCB security policy cache was introduced. Each PCB now caches
used security policies to avoid SP lookup for each packet.
o For inbound security policies added the mode, when the kernel does
check for full history of applied IPsec transforms.
o References counting rules for security policies and security
associations were changed. The proper SA locking added into xform
code.
o xform code was also changed. Now it is possible to unregister xforms.
tdb_xxx structures were changed and renamed to reflect changes in
SADB/SPDB, and changed rules for locking and refcounting.
Reviewed by: gnn, wblock
Obtained from: Yandex LLC
Relnotes: yes
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D9352
This interface type ("a parent interface of wlanX") is not used since
r287197
Reviewed by: adrian, glebius
Differential Revision: https://reviews.freebsd.org/D9308
(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.
Reviewed by: glebius
Obtained from: pfSense
MFC after: 2 weeks
Sponsored by: Rubicon Communications, LLC (Netgate)
- Add RATELIMIT kernel configuration keyword which must be set to
enable the new functionality.
- Add support for hardware driven, Receive Side Scaling, RSS aware, rate
limited sendqueues and expose the functionality through the already
established SO_MAX_PACING_RATE setsockopt(). The API support rates in
the range from 1 to 4Gbytes/s which are suitable for regular TCP and
UDP streams. The setsockopt(2) manual page has been updated.
- Add rate limit function callback API to "struct ifnet" which supports
the following operations: if_snd_tag_alloc(), if_snd_tag_modify(),
if_snd_tag_query() and if_snd_tag_free().
- Add support to ifconfig to view, set and clear the IFCAP_TXRTLMT
flag, which tells if a network driver supports rate limiting or not.
- This patch also adds support for rate limiting through VLAN and LAGG
intermediate network devices.
- How rate limiting works:
1) The userspace application calls setsockopt() after accepting or
making a new connection to set the rate which is then stored in the
socket structure in the kernel. Later on when packets are transmitted
a check is made in the transmit path for rate changes. A rate change
implies a non-blocking ifp->if_snd_tag_alloc() call will be made to the
destination network interface, which then sets up a custom sendqueue
with the given rate limitation parameter. A "struct m_snd_tag" pointer is
returned which serves as a "snd_tag" hint in the m_pkthdr for the
subsequently transmitted mbufs.
2) When the network driver sees the "m->m_pkthdr.snd_tag" different
from NULL, it will move the packets into a designated rate limited sendqueue
given by the snd_tag pointer. It is up to the individual drivers how the rate
limited traffic will be rate limited.
3) Route changes are detected by the NIC drivers in the ifp->if_transmit()
routine when the ifnet pointer in the incoming snd_tag mismatches the
one of the network interface. The network adapter frees the mbuf and
returns EAGAIN which causes the ip_output() to release and clear the send
tag. Upon next ip_output() a new "snd_tag" will be tried allocated.
4) When the PCB is detached the custom sendqueue will be released by a
non-blocking ifp->if_snd_tag_free() call to the currently bound network
interface.
Reviewed by: wblock (manpages), adrian, gallatin, scottl (network)
Differential Revision: https://reviews.freebsd.org/D3687
Sponsored by: Mellanox Technologies
MFC after: 3 months
sources to return timestamps when SO_TIMESTAMP is enabled. Two additional
clock sources are:
o nanosecond resolution realtime clock (equivalent of CLOCK_REALTIME);
o nanosecond resolution monotonic clock (equivalent of CLOCK_MONOTONIC).
In addition to this, this option provides unified interface to get bintime
(equivalent of using SO_BINTIME), except it also supported with IPv6 where
SO_BINTIME has never been supported. The long term plan is to depreciate
SO_BINTIME and move everything to using SO_TS_CLOCK.
Idea for this enhancement has been briefly discussed on the Net session
during dev summit in Ottawa last June and the general input was positive.
This change is believed to benefit network benchmarks/profiling as well
as other scenarios where precise time of arrival measurement is necessary.
There are two regression test cases as part of this commit: one extends unix
domain test code (unix_cmsg) to test new SCM_XXX types and another one
implementis totally new test case which exchanges UDP packets between two
processes using both conventional methods (i.e. calling clock_gettime(2)
before recv(2) and after send(2)), as well as using setsockopt()+recv() in
receive path. The resulting delays are checked for sanity for all supported
clock types.
Reviewed by: adrian, gnn
Differential Revision: https://reviews.freebsd.org/D9171
The caller may unlink a prefix before purging referencing addresses. An
identical assertion in nd6_prefix_del() verifies that the addresses are
purged before the prefix is freed.
PR: 215372
X-MFC With: r306829
This can lead to change of mbuf pointer (packet filter could do m_pullup(),
NAT, etc). Also in case of change of destination address, tryforward can
decide that packet should be handled by local system. In this case modified
mbuf can be returned to the ip[6]_input(). To handle this correctly, check
M_FASTFWD_OURS flag after return from ip[6]_tryforward. And if it is present,
update variables that depend from mbuf pointer and skip another inbound
firewall processing.
No objection from: #network
MFC after: 3 weeks
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D8764
Add rcvif local variable to keep inbound interface pointer. Count
ifs6_in_discard errors in all "goto bad" cases. Now it will count
errors even if mbuf was freed. Modify all places where m->m_pkthdr.rcvif
is used to use local rcvif variable.
Obtained from: Yandex LLC
MFC after: 1 month
for IPv6.
It gets performance benefits from reduced number of checks. It doesn't
copy mbuf to be able send ICMPv6 error message, because it keeps mbuf
unchanged until the moment, when the route decision has been made.
It doesn't do IPsec checks, and when some IPsec security policies present,
ip6_input() uses normal slow path.
Reviewed by: bz, gnn
Obtained from: Yandex LLC
MFC after: 1 month
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D8527
The tools using to generate the sources has been updated and produces
different whitespaces. Commit this seperately to avoid intermixing
these with real code changes.
MFC after: 3 days
handling. Ensure that:
* Protocol unreachable errors are handled by indicating ECONNREFUSED
to the TCP user for both IPv4 and IPv6. These were ignored for IPv6.
* Communication prohibited errors are handled by indicating ECONNREFUSED
to the TCP user for both IPv4 and IPv6. These were ignored for IPv6.
* Hop Limited exceeded errors are handled by indicating EHOSTUNREACH
to the TCP user for both IPv4 and IPv6.
For IPv6 the TCP connected was dropped but errno wasn't set.
Reviewed by: gallatin, rrs
MFC after: 1 month
Sponsored by: Netflix
Differential Revision: 7904
This change extends the nd6 lock to protect the ND prefix list as well
as the list of advertising routers associated with each prefix. To handle
cases where the nd6 lock must be dropped while iterating over either the
prefix or default router lists, a generation counter is used to track
modifications to the lists. Additionally, a new mutex is used to serialize
prefix on-link/off-link transitions. This mutex must be acquired before
the nd6 lock and is held while updating the routing table in
nd6_prefix_onlink() and nd6_prefix_offlink().
Reviewed by: ae, tuexen (SCTP bits)
Tested by: Jason Wolfe <jason@llnw.com>,
Larry Rosenman <ler@lerctr.org>
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D8125
