Commit Graph

186 Commits

Author SHA1 Message Date
Gleb Smirnoff
bbaa3f944e Fix SIOCDIFADDR semantics: if no address is specified, then delete first one. 2011-11-22 19:37:57 +00:00
Gleb Smirnoff
cf00e5c6b7 This check isn't needed now, sanity checking done in the beginning.
Missed it in last commit.
2011-11-21 20:07:12 +00:00
Gleb Smirnoff
6d00fd9c2d Historically in_control() did not check sockaddrs supplied with
structs ifreq/in_aliasreq and there've been several panics due
to that problem. All these panics were fixed just a couple of
lines above the panicing code.

Take a more general approach: sanity check sockaddrs supplied
with SIOCAIFADDR and SIOCSIF*ADDR at the beggining of the
function and drop all checks below.

One check is now disabled due to strange code in ifconfig(8)
that I've removed recently. I'm going to enable it with next
__FreeBSD_version bump.

Historically in_ifinit() was able to recover from an error
and restore old address. Nowadays this feature isn't working
for all error cases, but for some of them. I suppose no software
relies on this behavior, so I'd like to remove it, since this
simplifies code a lot.

Also, move if_scrub() earlier in the in_ifinit(). It is more
correct to wipe routes before removing address from local
address list, and interface address list.

Silence from:	bz, brooks, andre, rwatson, 3 weeks
2011-11-21 14:10:13 +00:00
Qing Li
b3664a14cc Exclude host routes when checking for prefix coverage on multiple
interfaces. A host route has a NULL mask so check for that condition.
I have also been told by developers who customize the packet output
path with direct manipulation of the route entry (or the outgoing
interface to be specific). This patch checks for the route mask
explicitly to make sure custom code will not panic.

PR:		kern/161805
MFC after:	3 days
2011-10-25 04:06:29 +00:00
Gleb Smirnoff
53883e0c24 Add support for IPv4 /31 prefixes, as described in RFC3021.
To run a /31 network, participating hosts MUST drop support
for directed broadcasts, and treat the first and last addresses
on subnet as unicast. The broadcast address for the prefix
should be the link local broadcast address, INADDR_BROADCAST.
2011-10-15 18:41:25 +00:00
Gleb Smirnoff
b365d954cc Remove last remnants of classful addressing:
- Remove ia_net, ia_netmask, ia_netbroadcast from struct in_ifaddr.
- Remove net.inet.ip.subnetsarelocal, I bet no one need it in 2011.
- fix bug when we were not forwarding to a host which matches classful
  net address. For example router having 192.168.x.y/16 network attached,
  would not forward traffic to 192.168.*.0, which are legal IPs in
  CIDR world.
- For compatibility, leave autoguessing of mask based on class.

Reviewed by:	andre, bz, rwatson
2011-10-15 16:28:06 +00:00
Gleb Smirnoff
a0b5928b29 De-spl(9). 2011-10-13 13:30:41 +00:00
Qing Li
15d2521975 All indirect routes will fail the rtcheck, except for a special host
route where the destination IP and the gateway IP is the same. This
special case handling is only meant for backward compatibility reason.
The last commit introduced a bug in the route check logic, where a
valid special case is treated as an error. This patch fixes that bug
along with some code cleanup.

Suggested by:	gleb
Reviewed by:	kmacy, discussed with gleb
MFC after:	1 day
2011-10-10 17:41:11 +00:00
Qing Li
6703e7ea10 Do not try removing an ARP entry associated with a given interface
address if that interface does not support ARP. Otherwise the
system will generate error messages unnecessarily due to the missing
entry.

PR:		kern/159602
Submitted by:	pluknet
MFC after:	3 days
2011-10-07 22:22:19 +00:00
Qing Li
41b210c6f6 Remove the reference held on the loopback route when the interface
address is being deleted. Only the last reference holder deletes the
loopback route. All other delete operations just clear the IFA_RTSELF
flag.

PR:		kern/159601
Submitted by:	pluknet
Reviewed by:	discussed on net@
MFC after:	3 days
2011-10-07 18:01:34 +00:00
Qing Li
db92413e6a A system may have multiple physical interfaces, all of which are on the
same prefix. Since a single route entry is installed for the prefix
(without RADIX_MPATH), incoming packets on the interfaces that are not
associated with the prefix route may trigger an error message about
unable to allocation LLE entry, and fails L2. This patch makes sure a
valid route is present in the system, and allow the aforementioned
condition to exist and treats as valid.

Reviewed by:	bz
MFC after:	5 days
2011-10-03 19:51:18 +00:00
Qing Li
6cf8e3300e This patch allows ARP to work properly in the presence of
self-referencing routes. This patch is a rework of r223862.

Reviewed by:	bz, zec
MFC after:	5 days
2011-10-03 19:06:55 +00:00
Qing Li
1184509858 When an interface address route is removed from the system, another
route with the same prefix is searched for as a replacement. The
current code did not bypass routes that have non-operational
interfaces. This patch fixes that bug and will find a replacement
route with an active interface.

PR:		kern/159603
Submitted by:	pluknet, ambrisko at ambrisko dot com
Reviewed by:	discussed on net@
Approved by:	re (bz)
MFC after:	3 days
2011-08-28 00:14:40 +00:00
Kevin Lo
7236660627 If RTF_HOST flag is specified, then we are interested in destination
address.

PR:		kern/159600
Submitted by:	Svatopluk Kraus <onwahe at gmail dot com>
Approved by:	re (hrs)
2011-08-10 06:17:06 +00:00
Marko Zec
13e255fab7 Permit ARP to proceed for IPv4 host routes for which the gateway is the
same as the host address.  This already works fine for INET6 and ND6.

While here, remove two function pointers from struct lltable which are
only initialized but never used.

MFC after:	3 days
2011-07-08 09:38:33 +00:00
Qing Li
92322284cd Supply the LLE_STATIC flag bit to in_ifscurb() when scrubbing interface
address so that proper clean up will take place in the routing code.
This patch fixes the bootp panic on startup problem. Also, added more
error handling and logging code in function in_scrubprefix().

MFC after:	5 days
2011-05-29 02:21:35 +00:00
Qing Li
5b84dc789a The statically configured (permanent) ARP entries are removed when an
interface is brought down, even though the interface address is still
valid. This patch maintains the permanent ARP entries as long as the
interface address (having the same prefix as that of the ARP entries)
is valid.

Reviewed by:	delphij
MFC after:	5 days
2011-05-20 19:12:20 +00:00
Sergey Kandaurov
79d514355c Reference ifaddr object before unlocking as it can be freed
from another context at the moment of later access.

PR:		kern/155555
Submitted by:	Andrew Boyer <aboyer att averesystems.com>
Approved by:	avg (mentor)
MFC after:	2 weeks
2011-03-21 14:19:40 +00:00
Gleb Smirnoff
a98c06f1c8 Use time_uptime instead of non-monotonic time_second to drive ARP
timeouts.

Suggested by:	bde
2010-11-30 15:57:00 +00:00
Dimitry Andric
3e288e6238 After some off-list discussion, revert a number of changes to the
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.
2010-11-22 19:32:54 +00:00
Dimitry Andric
31c6a0037e Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.
2010-11-14 20:38:11 +00:00
George V. Neville-Neil
e162ea60d4 Add a queue to hold packets while we await an ARP reply.
When a fast machine first brings up some non TCP networking program
it is quite possible that we will drop packets due to the fact that
only one packet can be held per ARP entry.  This leads to packets
being missed when a program starts or restarts if the ARP data is
not currently in the ARP cache.

This code adds a new sysctl, net.link.ether.inet.maxhold, which defines
a system wide maximum number of packets to be held in each ARP entry.
Up to maxhold packets are queued until an ARP reply is received or
the ARP times out.  The default setting is the old value of 1
which has been part of the BSD networking code since time
immemorial.

Expose the time we hold an incomplete ARP entry by adding
the sysctl net.link.ether.inet.wait, which defaults to 20
seconds, the value used when the new ARP code was added..

Reviewed by:	bz, rpaulo
MFC after: 3 weeks
2010-11-12 22:03:02 +00:00
Bjoern A. Zeeb
12112cf676 MfP4 CH182763 (original version):
Make it harder to exploit certain in_control() related races between the
intiial lookup at the beginning and the time we will remove the entry
from the lists by re-checking that entry is still in the list before
trying to remove it.

(*) It is believed that with the current code and locking strategy we
    cannot completely fix all race.

Reported by:	Nima Misaghian (nima_misa hotmail.com) on net@ 20100817
Tested by:	Nima Misaghian (nima_misa hotmail.com) (original version)
PR:		kern/146250
Submitted by:	Mikolaj Golub (to.my.trociny gmail.com) (different version)
MFC after:	1 week
2010-10-16 19:53:22 +00:00
Bjoern A. Zeeb
42db1b87d6 In case of RADIX_MPATH do not leak the IN_IFADDR read lock on
early return.

MFC after:	3 days
2010-09-04 16:06:01 +00:00
Will Andrews
54bfbd5153 Allow carp(4) to be loaded as a kernel module. Follow precedent set by
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
2010-08-11 00:51:50 +00:00
Qing Li
0ed6142b31 This patch fixes the problem where proxy ARP entries cannot be added
over the if_ng interface.

MFC after:	3 days
2010-05-25 20:42:35 +00:00
Bjoern A. Zeeb
82cea7e6f3 MFP4: @176978-176982, 176984, 176990-176994, 177441
"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
2010-04-29 11:52:42 +00:00
Bjoern A. Zeeb
becba438d2 Plug reference leaks in the link-layer code ("new-arp") that previously
prevented the link-layer entry from being freed.

In both in.c and in6.c (though that code path seems to be basically dead)
plug a reference leak in case of a pending callout being drained.

In if_ether.c consistently add a reference before resetting the callout
and in case we canceled a pending one remove the reference for that.
In the final case in arptimer, before freeing the expired entry, remove
the reference again and explicitly call callout_stop() to clear the active
flag.

In nd6.c:nd6_free() we are only ever called from the callout function and
thus need to remove the reference there as well before calling into
llentry_free().

In if_llatbl.c when freeing entire tables make sure that in case we cancel
a pending callout to remove the reference as well.

Reviewed by:		qingli (earlier version)
MFC after:		10 days
Problem observed, patch tested by: simon on ipv6gw.f.o,
			Christian Kratzer (ck cksoft.de),
			Evgenii Davidov (dado korolev-net.ru)
PR:			kern/144564
Configurations still affected:	with options FLOWTABLE
2010-04-11 16:04:08 +00:00
Qing Li
c7ea0aa648 One of the advantages of enabling ECMP (a.k.a RADIX_MPATH) is to
allow for connection load balancing across interfaces. Currently
the address alias handling method is colliding with the ECMP code.
For example, when two interfaces are configured on the same prefix,
only one prefix route is installed. So connection load balancing
among the available interfaces is not possible.

The other advantage of ECMP is for failover. The issue with the
current code, is that the interface link-state is not reflected
in the route entry. For example, if there are two interfaces on
the same prefix, the cable on one interface is unplugged, new and
existing connections should switch over to the other interface.
This is not done today and packets go into a black hole.

Also, there is a small bug in the kernel where deleting ECMP routes
in the userland will always return an error even though the command
is successfully executed.

MFC after:	5 days
2010-03-09 01:11:45 +00:00
Qing Li
d577d18a00 Some of the existing ppp and vpn related scripts create and set
the IP addresses of the tunnel end points to the same value. In
these cases the loopback route is not installed for the local
end.

Verified by:	avg
MFC after:	5 days
2010-02-02 20:38:30 +00:00
Qing Li
646c800540 Ensure an address is removed from the interface address
list when the installation of that address fails.

PR:		139559
2010-01-08 17:49:24 +00:00
Qing Li
ccbb9c359d Consolidate the route message generation code for when address
aliases were added or deleted. The announced route entry for
an address alias is no longer empty because this empty route
entry was causing some route daemon to fail and exit abnormally.

MFC after:	5 days
2009-12-30 22:13:01 +00:00
Qing Li
c7ab66020f The proxy arp entries could not be added into the system over the
IFF_POINTOPOINT link types. The reason was due to the routing
entry returned from the kernel covering the remote end is of an
interface type that does not support ARP. This patch fixes this
problem by providing a hint to the kernel routing code, which
indicates the prefix route instead of the PPP host route should
be returned to the caller. Since a host route to the local end
point is also added into the routing table, and there could be
multiple such instantiations due to multiple PPP links can be
created with the same local end IP address, this patch also fixes
the loopback route installation failure problem observed prior to
this patch. The reference count of loopback route to local end would
be either incremented or decremented. The first instantiation would
create the entry and the last removal would delete the route entry.

MFC after:	5 days
2009-12-30 21:35:34 +00:00
Qing Li
6cb2b4e7a8 Use the correct option name in the preprocessor command to enable
or disable diagnostic messages.

Reviewed by:	ru
MFC after:	3 days
2009-10-23 18:27:34 +00:00
Qing Li
93704ac5d7 This patch fixes the following issues in the ARP operation:
1. There is a regression issue in the ARP code. The incomplete
   ARP entry was timing out too quickly (1 second timeout), as
   such, a new entry is created each time arpresolve() is called.
   Therefore the maximum attempts made is always 1. Consequently
   the error code returned to the application is always 0.
2. Set the expiration of each incomplete entry to a 20-second
   lifetime.
3. Return "incomplete" entries to the application.

Reviewed by:	kmacy
MFC after:	3 days
2009-10-15 06:12:04 +00:00
Qing Li
b4a22c365c Remove a log message from production code. This log message can be
triggered by a misconfigured host that is sending out gratuious ARPs.
This log message can also be triggered during a network renumbering
event when multiple prefixes co-exist on a single network segment.

MFC after:	immediately
2009-10-02 01:45:11 +00:00
Qing Li
fa3cfd39ff Previously, if an address alias is configured on an interface, and
this address alias has a prefix matching that of another address
configured on the same interface, then the ARP entry for the alias
is not deleted from the ARP table when that address alias is removed.
This patch fixes the aforementioned issue.

PR:		kern/139113
MFC after:	3 days
2009-10-02 01:34:55 +00:00
Qing Li
9bb7d0f47a Self pointing routes are installed for configured interface addresses
and address aliases. After an interface is brought down and brought
back up again, those self pointing routes disappeared. This patch
ensures after an interface is brought back up, the loopback routes
are reinstalled properly.

Reviewed by:	bz
MFC after:	immediately
2009-09-15 19:18:34 +00:00
Qing Li
96ed1732bb The bootp code installs an interface address and the nfs client
module tries to install the same address again. This extra code
is removed, which was discovered by the removal of a call to
in_ifscrub() in r196714. This call to in_ifscrub is put back here
because the SIOCAIFADDR command can be used to change the prefix
length of an existing alias.

Reviewed by:    kmacy
2009-09-15 01:01:03 +00:00
Navdeep Parhar
9a31144537 Add arp_update_event. This replaces route_arp_update_event, which
has not worked since the arp-v2 rewrite.

The event handler will be called with the llentry write-locked and
can examine la_flags to determine whether the entry is being added
or removed.

Reviewed by:	gnn, kmacy
Approved by:	gnn (mentor)
MFC after:	1 month
2009-09-08 21:17:17 +00:00
Qing Li
1bf38b1292 This patch fixes the following issues:
- Routing messages are not generated when adding and removing
  interface address aliases.
- Loopback route installed for an interface address alias is
  not deleted from the routing table when that address alias
  is removed from the associated interface.
- Function in_ifscrub() is called extraneously.

Reviewed by:	gnn, kmacy, sam
MFC after:	3 days
2009-08-31 21:02:48 +00:00
Robert Watson
dc56e98f0d Use locks specific to the lltable code, rather than borrow the ifnet
list/index locks, to protect link layer address tables.  This avoids
lock order issues during interface teardown, but maintains the bug that
sysctl copy routines may be called while a non-sleepable lock is held.

Reviewed by:	bz, kmacy
MFC after:	3 days
2009-08-25 09:52:38 +00:00
Robert Watson
77dfcdc445 Rework global locks for interface list and index management, correcting
several critical bugs, including race conditions and lock order issues:

Replace the single rwlock, ifnet_lock, with two locks, an rwlock and an
sxlock.  Either can be held to stablize the lists and indexes, but both
are required to write.  This allows the list to be held stable in both
network interrupt contexts and sleepable user threads across sleeping
memory allocations or device driver interactions.  As before, writes to
the interface list must occur from sleepable contexts.

Reviewed by:	bz, julian
MFC after:	3 days
2009-08-23 20:40:19 +00:00
Robert Watson
530c006014 Merge the remainder of kern_vimage.c and vimage.h into vnet.c and
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)
2009-08-01 19:26:27 +00:00
Qing Li
df813b7ea2 This patch does the following:
- Allow loopback route to be installed for address assigned to
      interface of IFF_POINTOPOINT type.
    - Install loopback route for an IPv4 interface addreess when the
      "useloopback" sysctl variable is enabled. Similarly, install
      loopback route for an IPv6 interface address when the sysctl variable
      "nd6_useloopback" is enabled. Deleting loopback routes for interface
      addresses is unconditional in case these sysctl variables were
      disabled after an interface address has been assigned.

Reviewed by:	bz
Approved by:	re
2009-07-27 17:08:06 +00:00
Robert Watson
1e77c1056a Remove unused VNET_SET() and related macros; only VNET_GET() is
ever actually used.  Rename VNET_GET() to VNET() to shorten
variable references.

Discussed with:	bz, julian
Reviewed by:	bz
Approved by:	re (kensmith, kib)
2009-07-16 21:13:04 +00:00
Robert Watson
eddfbb763d Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(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)
2009-07-14 22:48:30 +00:00
Robert Watson
2d9cfabad4 Add a new global rwlock, in_ifaddr_lock, which will synchronize use of the
in_ifaddrhead and INADDR_HASH address lists.

Previously, these lists were used unsynchronized as they were effectively
never changed in steady state, but we've seen increasing reports of
writer-writer races on very busy VPN servers as core count has gone up
(and similar configurations where address lists change frequently and
concurrently).

For the time being, use rwlocks rather than rmlocks in order to take
advantage of their better lock debugging support.  As a result, we don't
enable ip_input()'s read-locking of INADDR_HASH until an rmlock conversion
is complete and a performance analysis has been done.  This means that one
class of reader-writer races still exists.

MFC after:      6 weeks
Reviewed by:    bz
2009-06-25 11:52:33 +00:00
Robert Watson
8c0fec805f Modify most routines returning 'struct ifaddr *' to return references
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)
2009-06-23 20:19:09 +00:00
Robert Watson
1099f828b3 Clean up common ifaddr management:
- 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
2009-06-21 19:30:33 +00:00