Add if_requestencap() interface method which is capable of calculating
various link headers for given interface. Right now there is support
for INET/INET6/ARP llheader calculation (IFENCAP_LL type request).
Other types are planned to support more complex calculation
(L2 multipath lagg nexthops, tunnel encap nexthops, etc..).
Reshape 'struct route' to be able to pass additional data (with is length)
to prepend to mbuf.
These two changes permits routing code to pass pre-calculated nexthop data
(like L2 header for route w/gateway) down to the stack eliminating the
need for other lookups. It also brings us closer to more complex scenarios
like transparently handling MPLS nexthops and tunnel interfaces.
Last, but not least, it removes layering violation introduced by flowtable
code (ro_lle) and simplifies handling of existing if_output consumers.
ARP/ND changes:
Make arp/ndp stack pre-calculate link header upon installing/updating lle
record. Interface link address change are handled by re-calculating
headers for all lles based on if_lladdr event. After these changes,
arpresolve()/nd6_resolve() returns full pre-calculated header for
supported interfaces thus simplifying if_output().
Move these lookups to separate ether_resolve_addr() function which ether
returs error or fully-prepared link header. Add <arp|nd6_>resolve_addr()
compat versions to return link addresses instead of pre-calculated data.
BPF changes:
Raw bpf writes occupied _two_ cases: AF_UNSPEC and pseudo_AF_HDRCMPLT.
Despite the naming, both of there have ther header "complete". The only
difference is that interface source mac has to be filled by OS for
AF_UNSPEC (controlled via BIOCGHDRCMPLT). This logic has to stay inside
BPF and not pollute if_output() routines. Convert BPF to pass prepend data
via new 'struct route' mechanism. Note that it does not change
non-optimized if_output(): ro_prepend handling is purely optional.
Side note: hackish pseudo_AF_HDRCMPLT is supported for ethernet and FDDI.
It is not needed for ethernet anymore. The only remaining FDDI user is
dev/pdq mostly untouched since 2007. FDDI support was eliminated from
OpenBSD in 2013 (sys/net/if_fddisubr.c rev 1.65).
Flowtable changes:
Flowtable violates layering by saving (and not correctly managing)
rtes/lles. Instead of passing lle pointer, pass pointer to pre-calculated
header data from that lle.
Differential Revision: https://reviews.freebsd.org/D4102
the wrapper functions as used in r252511. We can directly use the
locking macros.
Reviewed by: jtl, rwatson
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D4731
bridge(4) interfaces have an if_type of IFT_BRIDGE, rather than
IFT_ETHER, even though they only support Ethernet-style links. This
caused in6_if2idlen to emit an "unknown link type (209)" warning to
the console every time it was called. Add IFT_BRIDGE to the case
statement in the appropriate place, indicating that it uses the same
IPv6 address format as other Ethernet-like interfaces.
MFC after: 1 week
Before the change, things like lle state were queried via
SIOCGNBRINFO_IN6 by ndp(8) for _each_ lle entry in dump.
This ioctl was added in 1999, probably to avoid touching rtsock code.
This change maps SIOCGNBRINFO_IN6 data to standard rtsock dump the
following way:
expire (already) maps to rtm_rmx.rmx_expire
isrouter -> rtm_flags & RTF_GATEWAY
asked -> rtm_rmx.rmx_pksent
state -> rtm_rmx.rmx_state (maps to rmx_weight via define)
Reviewed by: ae
When using lagg failover mode neither Gratuitous ARP (IPv4) or Unsolicited
Neighbour Advertisements (IPv6) are sent to notify other nodes that the
address may have moved.
This results is slow failover, dropped packets and network outages for the
lagg interface when the primary link goes down.
We now use the new if_link_state_change_cond with the force param set to
allow lagg to force through link state changes and hence fire a
ifnet_link_event which are now monitored by rip and nd6.
Upon receiving these events each protocol trigger the relevant
notifications:
* inet4 => Gratuitous ARP
* inet6 => Unsolicited Neighbour Announce
This also fixes the carp IPv6 NA's that stopped working after r251584 which
added the ipv6_route__llma route.
The new behavour can be controlled using the sysctls:
* net.link.ether.inet.arp_on_link
* net.inet6.icmp6.nd6_on_link
Also removed unused param from lagg_port_state and added descriptions for the
sysctls while here.
PR: 156226
MFC after: 1 month
Sponsored by: Multiplay
Differential Revision: https://reviews.freebsd.org/D4111
Certain interfaces (e.g. pfsync0) do not have ip6 addresses (in other words,
ifp->if_afdata[AF_INET6] is NULL). Ensure we don't panic when the MTU is
updated.
pfsync interfaces will never have ip6 support, because it's explicitly disabled
in in6_domifattach().
PR: 205194
Reviewed by: melifaro, hrs
Differential Revision: https://reviews.freebsd.org/D4522
LLE structure is mostly unchanged during its lifecycle: there are only 2
things relevant for fast path lookup code:
1) link-level address change. Since r286722, these updates are performed
under AFDATA WLOCK.
2) Some sort of feedback indicating that this particular entry is used so
we send NS to perform reachability verification instead of expiring entry.
The only signal that is needed from fast path is something like binary
yes/no.
The latter is solved by the following changes:
Special r_skip_req (introduced in D3688) value is used for fast path feedback.
It is read lockless by fast path, but updated under req_mutex mutex. If this
field is non-zero, then fast path will acquire lock and set it back to 0.
After transitioning to STALE state, callout timer is armed to run each
V_nd6_delay seconds to make sure that if packet was transmitted at the start
of given interval, we would be able to switch to PROBE state in V_nd6_delay
seconds as user expects.
(in STALE state) timer is rescheduled until original V_nd6_gctimer expires
keeping lle in STALE state (remaining timer value stored in lle_remtime).
(in STALE state) timer is rescheduled if packet was transmitted less that
V_nd6_delay seconds ago to make sure we transition to PROBE state exactly
after V_n6_delay seconds.
As a result, all packets towards lle in REACHABLE/STALE/PROBE states are handled
by fast path without acquiring lle read lock.
Differential Revision: https://reviews.freebsd.org/D3780
ip_dooptions(), icmp6_redirect_input(), in6_lltable_rtcheck(),
in6p_lookup_mcast_ifp() and in6_selecthlim() use new routing api.
Eliminate now-unused ip_rtaddr().
Fix lookup key fib6_lookup_nh_basic() which was lost diring merge.
Make fib6_lookup_nh_basic() and fib6_lookup_nh_extended() always
return IPv6 destination address with embedded scope. Currently
rw_gateway has it scope embedded, do the same for non-gatewayed
destinations.
Sponsored by: Yandex LLC
new return codes of -1 were mistakenly being considered "true". Callout_stop
now returns -1 to indicate the callout had either already completed or
was not running and 0 to indicate it could not be stopped. Also update
the manual page to make it more consistent no non-zero in the callout_stop
or callout_reset descriptions.
MFC after: 1 Month with associated callout change.
instead of old "ignore-and-return 0" in r287789. This broke arp -da /
ndp -cn behavior (they exit on rtsock command failure). Fix this by
translating LLE_IFADDR to RTM_PINNED flag, passing it to userland and
making arp/ndp ignore these entries in batched delete.
MFC after: 2 weeks
without holding afdata wlock
* convert per-af delete_address callback to global lltable_delete_entry() and
more low-level "delete this lle" per-af callback
* fix some bugs/inconsistencies in IPv4/IPv6 ifscrub procedures
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D3573
interface but in6if_do_dad() already had a check for IFF_LOOPBACK.
- Remove in6if_do_dad() check in in6_broadcast_ifa(). An address
which needs DAD always has IN6_IFF_TENTATIVE there.
- in6if_do_dad() now returns EAGAIN when the interface is not ready
since DAD callout handler ignores such an interface.
- In DAD callout handler, mark an address as IN6_IFF_TENTATIVE
when the interface has ND6_IFF_IFDISABLED. And Do IFF_UP and
IFF_DRV_RUNNING check consistently when DAD is required.
- draft-ietf-6man-enhanced-dad is now published as RFC 7527.
- Fix some typos.
Before that, the logic besides lle_create() was the following:
return existing if found, create if not. This behaviour was error-prone
since we had to deal with 'sudden' static<>dynamic lle changes.
This commit fixes bunch of different issues like:
- refcount leak when lle is converted to static.
Simple check case:
console 1:
while true;
do for i in `arp -an|awk '$4~/incomp/{print$2}'|tr -d '()'`;
do arp -s $i 00:22:44:66:88:00 ; arp -d $i;
done;
done
console 2:
ping -f any-dead-host-in-L2
console 3:
# watch for memory consumption:
vmstat -m | awk '$1~/lltable/{print$2}'
- possible problems in arptimer() / nd6_timer() when dropping/reacquiring
lock.
New logic explicitly handles use-or-create cases in every lla_create
user. Basically, most of the changes are purely mechanical. However,
we explicitly avoid using existing lle's for interface/static LLE records.
* While here, call lle_event handlers on all real table lle change.
* Create lltable_free_entry() calling existing per-lltable
lle_free_t callback for entry deletion
This permits us having all (not fully true yet) all the info
needed in lookup process in first 64 bytes of 'struct llentry'.
struct llentry layout:
BEFORE:
[rwlock .. state .. state .. MAC ] (lle+1) [sockaddr_in[6]]
AFTER
[ in[6]_addr MAC .. state .. rwlock ]
Currently, address part of struct llentry has only 16 bytes for the key.
However, lltable does not restrict any custom lltable consumers with long
keys use the previous approach (store key at (lle+1)).
Sponsored by: Yandex LLC
* Split lltable_init() into lltable_allocate_htbl() (alloc
hash table with default callbacks) and lltable_link() (
links any lltable to the list).
* Switch from LLTBL_HASHTBL_SIZE to per-lltable hash size field.
* Move lltable setup to separate functions in in[6]_domifattach.
differences between projects/routing and HEAD.
This commit tries to keep code logic the same while changing underlying
code to use unified callbacks.
* Add llt_foreach_entry method to traverse all entries in given llt
* Add llt_dump_entry method to export particular lle entry in sysctl/rtsock
format (code is not indented properly to minimize diff). Will be fixed
in the next commits.
* Add llt_link_entry/llt_unlink_entry methods to link/unlink particular lle.
* Add llt_fill_sa_entry method to export address in the lle to sockaddr
format.
* Add llt_hash method to use in generic hash table support code.
* Add llt_free_entry method which is used in llt_prefix_free code.
* Prepare for fine-grained locking by separating lle unlink and deletion in
lltable_free() and lltable_prefix_free().
* Provide lltable_get<ifp|af>() functions to reduce direct 'struct lltable'
access by external callers.
* Remove @llt agrument from lle_free() lle callback since it was unused.
* Temporarily add L3_CADDR() macro for 'const' sockaddr typecasting.
* Switch to per-af hashing code.
* Rename LLE_FREE_LOCKED() callback from in[6]_lltable_free() to
in_[6]lltable_destroy() to avoid clashing with llt_free_entry() method.
Update description from these functions.
* Use unified lltable_free_entry() function instead of per-af one.
Reviewed by: ae
* Move lle creation/deletion from lla_lookup to separate functions:
lla_lookup(LLE_CREATE) -> lla_create
lla_lookup(LLE_DELETE) -> lla_delete
lla_create now returns with LLE_EXCLUSIVE lock for lle.
* Provide typedefs for new/existing lltable callbacks.
Reviewed by: ae
Both are used to protect access to IP addresses lists and they can be
acquired for reading several times per packet. To reduce lock contention
it is better to use rmlock here.
Reviewed by: gnn (previous version)
Obtained from: Yandex LLC
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D3149
- Add no_dad and ignoreloop per-IF knob. no_dad disables DAD completely,
and ignoreloop is to prevent infinite loop in loopback probing state when
loopback is permanently expected.
and arp were being used. They basically would pass in the
mutex to the callout_init. Because they used this method
to the callout system, it was possible to "stop" the callout.
When flushing the table and you stopped the running callout, the
callout_stop code would return 1 indicating that it was going
to stop the callout (that was about to run on the callout_wheel blocked
by the function calling the stop). Now when 1 was returned, it would
lower the reference count one extra time for the stopped timer, then
a few lines later delete the memory. Of course the callout_wheel was
stuck in the lock code and would then crash since it was accessing
freed memory. By using callout_init(c, 1) we always get a 0 back
and the reference counting bug does not rear its head. We do have
to make a few adjustments to the callouts themselves though to make
sure it does the proper thing if rescheduled as well as gets the lock.
Commented upon by hiren and sbruno
See Phabricator D1777 for more details.
Commented upon by hiren and sbruno
Reviewed by: adrian, jhb and bz
Sponsored by: Netflix Inc.
* Make most of lltable_* methods 'normal' functions instead of inline
* Add lltable_get_<af|ifp>() functions to access given lltable fields
* Temporarily resurrect nd6_lookup() function
use llt_fill_sa_entry() llt method to store lle address in sa.
* Eliminate L3_ADDR macro and either reference IPv4/IPv6 address
directly from lle or use newly-created llt_fill_sa_entry().
* Do not store sockaddr inside arp/ndp lle anymore.
and explicit calls to RTENTRY_FREE_LOCKED()
* Use lltable_prefix_free() in arp_ifscrub to be consistent with nd6.
* Rename <lltable_|llt>_delete function to _delete_addr() to note that
this function is used to external callers. Make this function maintain
its own locking.
* Use lookup/unlink/clear call chain from internal callers instead of
delete_addr.
* Fix LLE_DELETED flag handling
cleanup including unlinking/freeing
* Relax locking in lltable_prefix_free_af/lltable_free
* Do not pass @llt to lle free callback: it is always NULL now.
* Unify arptimer/nd6_llinfo_timer: explicitly unlock lle avoiding
unlock/lock sequinces
* Do not pass unlocked lle to nd6_ns_output(): add nd6_llinfo_get_holdsrc()
to retrieve preferred source address from lle hold queue and pass it
instead of lle.
* Finally, make nd6_create() create and return unlocked lle
* Separate defrtr handling code from nd6_free():
use nd6_check_del_defrtr() to check if we need to keep entry instead of
performing GC,
use nd6_check_recalc_defrtr() to perform actual recalc on lle removal.
* Move isRouter handling from nd6_cache_lladdr() to separate
nd6_check_router()
* Add initial code to maintain lle runtime flags in sync.
does actual new lle creation without extensive locking and existing
lle search.
Move lle updating code from gigantic in_arpinput() to arp_update_llle()
and some other functions.
IPv6 changes to follow.
use rwlock accessible via external functions
(IF_AFDATA_CFG_* -> if_afdata_cfg_*()) for all control plane tasks
use rmlock (IF_AFDATA_RUN_*) for fast-path lookups.
