because a link where looped back NS messages are permanently observed
does not work with either NDP or ARP for IPv4.
- draft-ietf-6man-enhanced-dad is now RFC 7527.
Discussed with: hiren
MFC after: 3 days
It is acceptable that the size can be equal to MCLBYTES. In the later
KAME's code this check has been moved under DIAGNOSTIC ifdef, because
the size of NA and NS is much smaller than MCLBYTES. So, it is safe to
replace the check with KASSERT.
PR: 199304
Discussed with: glebius
MFC after: 1 week
- 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.
to initialize mbuf's fibnum. Uninitialized fibnum value can lead to
panic in the routing code. Currently we use only RT_DEFAULT_FIB value
for initialization.
Differential Revision: https://reviews.freebsd.org/D1998
Reviewed by: hrs (previous version)
Sponsored by: Yandex LLC
draft-ietf-6man-enhanced-dad-13.
This basically adds a random nonce option (RFC 3971) to NS messages
for DAD probe to detect a looped back packet. This looped back packet
prevented DAD on some pseudo-interfaces which aggregates multiple L2 links
such as lagg(4).
The length of the nonce is set to 6 bytes. This algorithm can be disabled by
setting net.inet6.ip6.dad_enhanced sysctl to 0 in a per-vnet basis.
Reported by: hiren
Reviewed by: ae
Differential Revision: https://reviews.freebsd.org/D1835
hold mbuf chain instead of calling full-blown nd6_output_lle()
for each packet. This simplifies both callers and nd6_output_lle()
implementation.
* Make nd6_output_lle() static and remove now-unused lle and chain
arguments.
* Rename nd6_output_flush() -> nd6_flush_holdchain() to be consistent.
* Move all pre-send transmit hooks to newly-created nd6_output_ifp().
Now nd6_output(), nd6_output_lle() and nd6_flush_holdchain() are using
it to send mbufs to if_output.
* Remove SeND hook from nd6_na_input() because it was implemented
incorrectly since the beginning (r211501):
- it tagged initial input mbuf (m) instead of m_hold
- tagging _all_ mbufs in holdchain seems to be wrong anyway.
the knowledge of mbuf layout, and in particular constants such as M_EXT,
MLEN, MHLEN, and so on, in mbuf consumers by unifying various alignment
utility functions (M_ALIGN(), MH_ALIGN(), MEXT_ALIGN() in a single
M_ALIGN() macro, implemented by a now-inlined m_align() function:
- Move m_align() from uipc_mbuf.c to mbuf.h; mark as __inline.
- Reimplement M_ALIGN(), MH_ALIGN(), and MEXT_ALIGN() using m_align().
- Update consumers around the tree to simply use M_ALIGN().
This change eliminates a number of cases where mbuf consumers must be aware
of whether or not mbufs returned by the allocator use external storage, but
also assumptions about the size of the returned mbuf. This will make it
easier to introduce changes in how we use external storage, as well as
features such as variable-size mbufs.
Differential Revision: https://reviews.freebsd.org/D1436
Reviewed by: glebius, trasz, gnn, bz
Sponsored by: EMC / Isilon Storage Division
number of races which could cause double frees or use-after-frees when
performing DAD on an address. In particular, an IPv6 address can now only be
marked as a duplicate from the DAD callout.
Differential Revision: https://reviews.freebsd.org/D1258
Reviewed by: ae, hrs
Reported by: rstone
MFC after: 1 month
possible and do not clear IN6_IFF_TENTATIVE. If IFDISABLED was accidentally
set after a DAD started, TENTATIVE could be cleared because no NA was
received due to IFDISABLED, and as a result it could prevent DAD when
manually clearing IFDISABLED after that.
Thus we can use IF_AFDATA_RLOCK() instead of IF_AFDATA_LOCK() when doing
lla_lookup() without LLE_CREATE flag.
Reviewed by: glebius, adrian
MFC after: 1 week
Sponsored by: Yandex LLC
unlocked route. Use in6_rtalloc() instead of in6_rtalloc1. This helps
simplify the code and remove several now unused variables.
PR: 156283
MFC after: 2 weeks
- Do not calculate constant length values at run time,
CTASSERT() their sanity.
- Remove superfluous cleaning of mbuf fields after allocation.
- Replace compat macros with function calls.
Sponsored by: Nginx, Inc.
it skips FLOWTABLE lookup. However, the non-NULL ro has dual meaning
here: it may be supplied to provide route, and it may be supplied to
store and return to caller the route that ip_output()/ip6_output()
finds. In the latter case skipping FLOWTABLE lookup is pessimisation.
The difference between struct route filled by FLOWTABLE and filled
by rtalloc() family is that the former doesn't hold a reference on
its rtentry. Reference is hold by flow entry, and it is about to
be released in future. Thus, route filled by FLOWTABLE shouldn't
be passed to RTFREE() macro.
- Introduce new flag for struct route/route_in6, that marks route
not holding a reference on rtentry.
- Introduce new macro RO_RTFREE() that cleans up a struct route
depending on its kind.
- All callers to ip_output()/ip6_output() that do supply non-NULL
but empty route should use RO_RTFREE() to free results of
lookup.
- ip_output()/ip6_output() now do FLOWTABLE lookup always when
ro->ro_rt == NULL.
Tested by: tuexen (SCTP part)
Extend the so far IPv4-only support for multiple routing tables (FIBs)
introduced in r178888 to IPv6 providing feature parity.
This includes an extended rtalloc(9) KPI for IPv6, the necessary
adjustments to the network stack, and user land support as in netstat.
Sponsored by: Cisco Systems, Inc.
Reviewed by: melifaro (basically)
MFC after: 10 days
from scratch, copying needed functionality from the old implemenation
on demand, with a thorough review of all code. The main change is that
interface layer has been removed from the CARP. Now redundant addresses
are configured exactly on the interfaces, they run on.
The CARP configuration itself is, as before, configured and read via
SIOCSVH/SIOCGVH ioctls. A new prefix created with SIOCAIFADDR or
SIOCAIFADDR_IN6 may now be configured to a particular virtual host id,
which makes the prefix redundant.
ifconfig(8) semantics has been changed too: now one doesn't need
to clone carpXX interface, he/she should directly configure a vhid
on a Ethernet interface.
To supply vhid data from the kernel to an application the getifaddrs(8)
function had been changed to pass ifam_data with each address. [1]
The new implementation definitely closes all PRs related to carp(4)
being an interface, and may close several others. It also allows
to run a single redundant IP per interface.
Big thanks to Bjoern Zeeb for his help with inet6 part of patch, for
idea on using ifam_data and for several rounds of reviewing!
PR: kern/117000, kern/126945, kern/126714, kern/120130, kern/117448
Reviewed by: bz
Submitted by: bz [1]
- A new per-interface knob IFF_ND6_NO_RADR and sysctl IPV6CTL_NO_RADR.
This controls if accepting a route in an RA message as the default route.
The default value for each interface can be set by net.inet6.ip6.no_radr.
The system wide default value is 0.
- A new sysctl: net.inet6.ip6.norbit_raif. This controls if setting R-bit in
NA on RA accepting interfaces. The default is 0 (R-bit is set based on
net.inet6.ip6.forwarding).
Background:
IPv6 host/router model suggests a router sends an RA and a host accepts it for
router discovery. Because of that, KAME implementation does not allow
accepting RAs when net.inet6.ip6.forwarding=1. Accepting RAs on a router can
make the routing table confused since it can change the default router
unintentionally.
However, in practice there are cases where we cannot distinguish a host from
a router clearly. For example, a customer edge router often works as a host
against the ISP, and as a router against the LAN at the same time. Another
example is a complex network configurations like an L2TP tunnel for IPv6
connection to Internet over an Ethernet link with another native IPv6 subnet.
In this case, the physical interface for the native IPv6 subnet works as a
host, and the pseudo-interface for L2TP works as the default IP forwarding
route.
Problem:
Disabling processing RA messages when net.inet6.ip6.forwarding=1 and
accepting them when net.inet6.ip6.forward=0 cause the following practical
issues:
- A router cannot perform SLAAC. It becomes a problem if a box has
multiple interfaces and you want to use SLAAC on some of them, for
example. A customer edge router for IPv6 Internet access service
using an IPv6-over-IPv6 tunnel sometimes needs SLAAC on the
physical interface for administration purpose; updating firmware
and so on (link-local addresses can be used there, but GUAs by
SLAAC are often used for scalability).
- When a host has multiple IPv6 interfaces and it receives multiple RAs on
them, controlling the default route is difficult. Router preferences
defined in RFC 4191 works only when the routers on the links are
under your control.
Details of Implementation Changes:
Router Advertisement messages will be accepted even when
net.inet6.ip6.forwarding=1. More precisely, the conditions are as
follow:
(ACCEPT_RTADV && !NO_RADR && !ip6.forwarding)
=> Normal RA processing on that interface. (as IPv6 host)
(ACCEPT_RTADV && (NO_RADR || ip6.forwarding))
=> Accept RA but add the router to the defroute list with
rtlifetime=0 unconditionally. This effectively prevents
from setting the received router address as the box's
default route.
(!ACCEPT_RTADV)
=> No RA processing on that interface.
ACCEPT_RTADV and NO_RADR are per-interface knob. In short, all interface
are classified as "RA-accepting" or not. An RA-accepting interface always
processes RA messages regardless of ip6.forwarding. The difference caused by
NO_RADR or ip6.forwarding is whether the RA source address is considered as
the default router or not.
R-bit in NA on the RA accepting interfaces is set based on
net.inet6.ip6.forwarding. While RFC 6204 W-1 rule (for CPE case) suggests
a router should disable the R-bit completely even when the box has
net.inet6.ip6.forwarding=1, I believe there is no technical reason with
doing so. This behavior can be set by a new sysctl net.inet6.ip6.norbit_raif
(the default is 0).
Usage:
# ifconfig fxp0 inet6 accept_rtadv
=> accept RA on fxp0
# ifconfig fxp0 inet6 accept_rtadv no_radr
=> accept RA on fxp0 but ignore default route information in it.
# sysctl net.inet6.ip6.norbit_no_radr=1
=> R-bit in NAs on RA accepting interfaces will always be set to 0.
passing the cached proxydl reference (sockaddr_dl initialized or not) to
nd6_na_output(). nd6_na_output() will thus assume a proxy NA. Revert to
conditionally passing either &proxydl or NULL if no proxy case desired.
Tested by: ipv6gw and ref9-i386
Reported by: Pete French (petefrench ingresso.co.uk on stable)
Reported by: bz, simon on Y! cluster
Reported by: kib
PR: kern/151908
MFC after: 3 days
even after dropping the reference and unlocking. Previously we
have dereferenced a NULL pointer (after r121765).
Simply unlocking after the block does not work either because of
lock ordering (see r121765) and in addition we would still hold
a pointer to something that might be gone by the time we access it.
Thus take a copy of the value rather than just caching the pointer.
PR: kern/151908
Submitted by: chenyl (netstar2008 126.com) (initial version)
MFC after: 2 weeks
Call the handler function with the lock held, return unlocked as we
might free the entry. Rework functions later in the call graph to be
either called with the lock held or, only if needed, unlocked.
Place asserts to document and tighten assumptions on various lle locking,
which were not always true before.
We call nd6_ns_output() unlocked and the assignment of ip6->ip6_src was
decentralized to minimize possible complexity introduced with the formerly
missing locking there. This also resulted in a push down of local
variable scopes into smaller blocks.
Reported by: many
PR: kern/148857
Submitted by: Dmitrij Tejblum (tejblum yandex-team.ru) (original version)
MFC After: 4 days
DPCPU_DEFINE and VNET_DEFINE macros, as these cause problems for various
people working on the affected files. A better long-term solution is
still being considered. This reversal may give some modules empty
set_pcpu or set_vnet sections, but these are harmless.
Changes reverted:
------------------------------------------------------------------------
r215318 | dim | 2010-11-14 21:40:55 +0100 (Sun, 14 Nov 2010) | 4 lines
Instead of unconditionally emitting .globl's for the __start_set_xxx and
__stop_set_xxx symbols, only emit them when the set_vnet or set_pcpu
sections are actually defined.
------------------------------------------------------------------------
r215317 | dim | 2010-11-14 21:38:11 +0100 (Sun, 14 Nov 2010) | 3 lines
Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.
------------------------------------------------------------------------
r215316 | dim | 2010-11-14 21:23:02 +0100 (Sun, 14 Nov 2010) | 2 lines
Add macros to define static instances of VNET_DEFINE and DPCPU_DEFINE.
Add kernel side support for Secure Neighbor Discovery (SeND), RFC 3971.
The implementation consists of a kernel module that gets packets from
the nd6 code, sends them to user space on a dedicated socket and reinjects
them back for further processing.
Hooks are used from nd6 code paths to divert relevant packets to the
send implementation for processing in user space. The hooks are only
triggered if the send module is loaded. In case no user space
application is connected to the send socket, processing continues
normaly as if the module would not be loaded. Unloading the module
is not possible at this time due to missing nd6 locking.
The native SeND socket is similar to a raw IPv6 socket but with its own,
internal pseudo-protocol.
Approved by: bz (mentor)
bridge(4), lagg(4) etc. and make use of function pointers and
pf_proto_register() to hook carp into the network stack.
Currently, because of the uncertainty about whether the unload path is free
of race condition panics, unloads are disallowed by default. Compiling with
CARPMOD_CAN_UNLOAD in CFLAGS removes this anti foot shooting measure.
This commit requires IP6PROTOSPACER, introduced in r211115.
Reviewed by: bz, simon
Approved by: ken (mentor)
MFC after: 2 weeks
"Whitspace" churn after the VIMAGE/VNET whirls.
Remove the need for some "init" functions within the network
stack, like pim6_init(), icmp_init() or significantly shorten
others like ip6_init() and nd6_init(), using static initialization
again where possible and formerly missed.
Move (most) variables back to the place they used to be before the
container structs and VIMAGE_GLOABLS (before r185088) and try to
reduce the diff to stable/7 and earlier as good as possible,
to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9.
This also removes some header file pollution for putatively
static global variables.
Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are
no longer needed.
Reviewed by: jhb
Discussed with: rwatson
Sponsored by: The FreeBSD Foundation
Sponsored by: CK Software GmbH
MFC after: 6 days
automatic link-local address configuration:
- Convert a sysctl net.inet6.ip6.accept_rtadv to one for the
default value of a per-IF flag ND6_IFF_ACCEPT_RTADV, not a
global knob. The default value of the sysctl is 0.
- Add a new per-IF flag ND6_IFF_AUTO_LINKLOCAL and convert a
sysctl net.inet6.ip6.auto_linklocal to one for its default
value. The default value of the sysctl is 1.
- Make ND6_IFF_IFDISABLED more robust. It can be used to disable
IPv6 functionality of an interface now.
- Receiving RA is allowed if ip6_forwarding==0 *and*
ND6_IFF_ACCEPT_RTADV is set on that interface. The former
condition will be revisited later to support a "host + router" box
like IPv6 CPE router. The current behavior is compatible with
the older releases of FreeBSD.
- The ifconfig(8) now supports these ND6 flags as well as "nud",
"prefer_source", and "disabled" in ndp(8). The ndp(8) now
supports "auto_linklocal".
Discussed with: bz and jinmei
Reviewed by: bz
MFC after: 3 days
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks. Minor cleanups are done in the process,
and comments updated to reflect these changes.
Reviewed by: bz
Approved by: re (vimage blanket)
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator. Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...). This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.
Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack. Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory. Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.
Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy. Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address. When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.
This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.
Bump __FreeBSD_version and update UPDATING.
Portions submitted by: bz
Reviewed by: bz, zec
Discussed with: gnn, jamie, jeff, jhb, julian, sam
Suggested by: peter
Approved by: re (kensmith)
to save the selected source address rather than returning an
unreferenced copy to a pointer that might long be gone by the
time we use the pointer for anything meaningful.
Asked for by: rwatson
Reviewed by: rwatson
rather than pointers, requiring callers to properly dispose of those
references. The following routines now return references:
ifaddr_byindex
ifa_ifwithaddr
ifa_ifwithbroadaddr
ifa_ifwithdstaddr
ifa_ifwithnet
ifaof_ifpforaddr
ifa_ifwithroute
ifa_ifwithroute_fib
rt_getifa
rt_getifa_fib
IFP_TO_IA
ip_rtaddr
in6_ifawithifp
in6ifa_ifpforlinklocal
in6ifa_ifpwithaddr
in6_ifadd
carp_iamatch6
ip6_getdstifaddr
Remove unused macro which didn't have required referencing:
IFP_TO_IA6
This closes many small races in which changes to interface
or address lists while an ifaddr was in use could lead to use of freed
memory (etc). In a few cases, add missing if_addr_list locking
required to safely acquire references.
Because of a lack of deep copying support, we accept a race in which
an in6_ifaddr pointed to by mbuf tags and extracted with
ip6_getdstifaddr() doesn't hold a reference while in transmit. Once
we have mbuf tag deep copy support, this can be fixed.
Reviewed by: bz
Obtained from: Apple, Inc. (portions)
MFC after: 6 weeks (portions)
- Unify reference count and lock initialization in a single function,
ifa_init().
- Move tear-down from a macro (IFAFREE) to a function ifa_free().
- Move reference count bump from a macro (IFAREF) to a function ifa_ref().
- Instead of using a u_int protected by a mutex to refcount(9) for
reference count management.
The ifa_mtx is now used for exactly one ioctl, and possibly should be
removed.
MFC after: 3 weeks
previously always pointing to the default vnet context, to a
dynamically changing thread-local one. The currvnet context
should be set on entry to networking code via CURVNET_SET() macros,
and reverted to previous state via CURVNET_RESTORE(). Recursions
on curvnet are permitted, though strongly discuouraged.
This change should have no functional impact on nooptions VIMAGE
kernel builds, where CURVNET_* macros expand to whitespace.
The curthread->td_vnet (aka curvnet) variable's purpose is to be an
indicator of the vnet context in which the current network-related
operation takes place, in case we cannot deduce the current vnet
context from any other source, such as by looking at mbuf's
m->m_pkthdr.rcvif->if_vnet, sockets's so->so_vnet etc. Moreover, so
far curvnet has turned out to be an invaluable consistency checking
aid: it helps to catch cases when sockets, ifnets or any other
vnet-aware structures may have leaked from one vnet to another.
The exact placement of the CURVNET_SET() / CURVNET_RESTORE() macros
was a result of an empirical iterative process, whith an aim to
reduce recursions on CURVNET_SET() to a minimum, while still reducing
the scope of CURVNET_SET() to networking only operations - the
alternative would be calling CURVNET_SET() on each system call entry.
In general, curvnet has to be set in three typicall cases: when
processing socket-related requests from userspace or from within the
kernel; when processing inbound traffic flowing from device drivers
to upper layers of the networking stack, and when executing
timer-driven networking functions.
This change also introduces a DDB subcommand to show the list of all
vnet instances.
Approved by: julian (mentor)
macros: ICMPSTAT_ADD(), ICMPSTAT_INC(), ICMP6STAT_ADD(), and
ICMP6STAT_INC(), rather than directly manipulating the fields
of these structures across the kernel. This will make it
easier to change the implementation of these statistics,
such as using per-CPU versions of the data structures.
In on case, icmp6stat members are manipulated indirectly, by
icmp6_errcount(), and this will require further work to fix
for per-CPU stats.
MFC after: 3 days
a locked route. Thus we have to use RTFREE_LOCKED(9) to get it unlocked
and rtfree(9)d rather than just rtfree(9)d.
Since the PR was filed, new places with the same problem were added
with new code. Also check that the rt is valid before freeing it
either way there.
PR: kern/129793
Submitted by: Dheeraj Reddy <dheeraj@ece.gatech.edu>
MFC after: 2 weeks
Committed from: Bugathon #6
