Commit Graph

158 Commits

Author SHA1 Message Date
Qing Li
130fd3bc32 MFC r201319
Remove a deleted comment line that was brought back by
my previous commit.
2010-01-05 22:37:05 +00:00
Qing Li
32c5340155 MFC r201282, r201543
r201282
-------
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.

r201543
-------
The IFA_RTSELF address flag marks a loopback route has been installed
for the interface address. This marker is necessary to properly support
PPP types of links where multiple links can have the same local end
IP address. The IFA_RTSELF flag bit maps to the RTF_HOST value, which
was combined into the route flag bits during prefix installation in
IPv6. This inclusion causing the prefix route to be unusable. This
patch fixes this bug by excluding the IFA_RTSELF flag during route
installation.

PR:		ports/141342, kern/141134
2010-01-05 22:14:55 +00:00
Qing Li
553a7dec4b MFC r197227
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
Approved by:	re
2009-09-15 22:46:06 +00:00
Robert Watson
b569420afa Merge r196510 from head to stable/8:
Make if_grow static -- it's not used outside of if.c, and with the
  internals destined to change, it's better if it remains that way.

Approved by:	re (kib)
2009-08-28 21:07:43 +00:00
Robert Watson
3ef94f2b72 Merge r196481 from head to stable/8:
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

Approved by:	re (kib)
2009-08-28 20:06:02 +00:00
Robert Watson
aeba9e80ff Merge r196263 from head to stable/8:
Remove unused if_rawoutput() macro; it has been unused since at least
  FreeBSD 2.

Approved by:	re (kib)
2009-08-20 21:14:52 +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
Brooks Davis
6cb7f168db Remove support for the /dev/net/* per-interface devices. They serve
little purpose and are unused in the base system.

The IOCTL functionality is entirely duplicated and routing sockets
provide a richer interface than the kqueue functionality.

Further, it is not practical for these devices to be made sensible in
the face of VIMAGE.

Bump __FreeBSD_version on the off chance that there is any code out
there that actually uses this stuff.

Reviewed by:	rwatson
Discussed with:	bz, zec
Approved by:	re@ (kensmith)
2009-06-29 19:46:29 +00:00
Robert Watson
f9ef96ca71 Define four wrapper functions for interface address locking,
if_addr_rlock() and if_addr_runlock() for regular address lists, and
if_maddr_rlock() and if_maddr_runlock() for multicast address lists.

We will use these in various kernel modules to avoid encoding specific
type and locking strategy information into modules that currently use
IF_ADDR_LOCK() and IF_ADDR_UNLOCK() directly.

MFC after:	6 weeks
2009-06-26 00:36:47 +00:00
Robert Watson
8896f83a58 Add a new function, ifa_ifwithaddr_check(), which rather than returning
a pointer to an ifaddr matching the passed socket address, returns a
boolean indicating whether one was present.  In the (near) future,
ifa_ifwithaddr() will return a referenced ifaddr rather than a raw
ifaddr pointer, and the new wrapper will allow callers that care only
about the boolean condition to avoid having to free that reference.

MFC after:	3 weeks
2009-06-22 10:59:34 +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
Kip Macy
d49cd9a18e add helper function for flushing software queues 2009-06-19 23:11:20 +00:00
Sam Leffler
d659538f72 r193336 moved ifq_detach to if_free which broke if_alloc followed
by if_free (w/o doing if_attach); move ifq_attach to if_alloc and
rename ifq_attach/detach to ifq_init/ifq_delete to better identify
their purpose

Reviewed by:	jhb, kmacy
2009-06-15 19:50:03 +00:00
Kip Macy
a913be0917 - add drbr routines for accessing #qentries and conditionally dequeueing
- track bytes enqueued in buf_ring
2009-06-09 19:19:16 +00:00
Marko Zec
bc29160df3 Introduce an infrastructure for dismantling vnet instances.
Vnet modules and protocol domains may now register destructor
functions to clean up and release per-module state.  The destructor
mechanisms can be triggered by invoking "vimage -d", or a future
equivalent command which will be provided via the new jail framework.

While this patch introduces numerous placeholder destructor functions,
many of those are currently incomplete, thus leaking memory or (even
worse) failing to stop all running timers.  Many of such issues are
already known and will be incrementaly fixed over the next weeks in
smaller incremental commits.

Apart from introducing new fields in structs ifnet, domain, protosw
and vnet_net, which requires the kernel and modules to be rebuilt, this
change should have no impact on nooptions VIMAGE builds, since vnet
destructors can only be called in VIMAGE kernels.  Moreover,
destructor functions should be in general compiled in only in
options VIMAGE builds, except for kernel modules which can be safely
kldunloaded at run time.

Bump __FreeBSD_version to 800097.
Reviewed by:	bz, julian
Approved by:	rwatson, kib (re), julian (mentor)
2009-06-08 17:15:40 +00:00
Attilio Rao
1abcdbd127 When user_frac in the polling subsystem is low it is going to busy the
CPU for too long period than necessary.  Additively, interfaces are kept
polled (in the tick) even if no more packets are available.
In order to avoid such situations a new generic mechanism can be
implemented in proactive way, keeping track of the time spent on any
packet and fragmenting the time for any tick, stopping the processing
as soon as possible.

In order to implement such mechanism, the polling handler needs to
change, returning the number of packets processed.
While the intended logic is not part of this patch, the polling KPI is
broken by this commit, adding an int return value and the new flag
IFCAP_POLLING_NOCOUNT (which will signal that the return value is
meaningless for the installed handler and checking should be skipped).

Bump __FreeBSD_version in order to signal such situation.

Reviewed by:	emaste
Sponsored by:	Sandvine Incorporated
2009-05-30 15:14:44 +00:00
Marko Zec
e0c14af9b3 Introduce the if_vmove() function, which will be used in the future
for reassigning ifnets from one vnet to another.

if_vmove() works by calling a restricted subset of actions normally
executed by if_detach() on an ifnet in the current vnet, and then
switches to the target vnet and executes an appropriate subset of
if_attach() actions there.

if_attach() and if_detach() have become wrapper functions around
if_attach_internal() and if_detach_internal(), where the later
variants have an additional argument, a flag indicating whether a
full attach or detach sequence is to be executed, or only a
restricted subset suitable for moving an ifnet from one vnet to
another.  Hence, if_vmove() will not call if_detach() and if_attach()
directly, but will call the if_detach_internal() and
if_attach_internal() variants instead, with the vmove flag set.

While here, staticize ifnet_setbyindex() since it is not referenced
from outside of sys/net/if.c.

Also rename ifccnt field in struct vimage to ifcnt, and do some minor
whitespace garbage collection where appropriate.

This change should have no functional impact on nooptions VIMAGE kernel
builds.

Reviewed by:	bz, rwatson, brooks?
Approved by:	julian (mentor)
2009-05-22 22:09:00 +00:00
Marko Zec
21ca7b57bd Change the curvnet variable from a global const struct vnet *,
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)
2009-05-05 10:56:12 +00:00
Marko Zec
f6dfe47a14 Permit buiding kernels with options VIMAGE, restricted to only a single
active network stack instance.  Turning on options VIMAGE at compile
time yields the following changes relative to default kernel build:

1) V_ accessor macros for virtualized variables resolve to structure
fields via base pointers, instead of being resolved as fields in global
structs or plain global variables.  As an example, V_ifnet becomes:

    options VIMAGE:          ((struct vnet_net *) vnet_net)->_ifnet
    default build:           vnet_net_0._ifnet
    options VIMAGE_GLOBALS:  ifnet

2) INIT_VNET_* macros will declare and set up base pointers to be used
by V_ accessor macros, instead of resolving to whitespace:

    INIT_VNET_NET(ifp->if_vnet); becomes

    struct vnet_net *vnet_net = (ifp->if_vnet)->mod_data[VNET_MOD_NET];

3) Memory for vnet modules registered via vnet_mod_register() is now
allocated at run time in sys/kern/kern_vimage.c, instead of per vnet
module structs being declared as globals.  If required, vnet modules
can now request the framework to provide them with allocated bzeroed
memory by filling in the vmi_size field in their vmi_modinfo structures.

4) structs socket, ifnet, inpcbinfo, tcpcb and syncache_head are
extended to hold a pointer to the parent vnet.  options VIMAGE builds
will fill in those fields as required.

5) curvnet is introduced as a new global variable in options VIMAGE
builds, always pointing to the default and only struct vnet.

6) struct sysctl_oid has been extended with additional two fields to
store major and minor virtualization module identifiers, oid_v_subs and
oid_v_mod.  SYSCTL_V_* family of macros will fill in those fields
accordingly, and store the offset in the appropriate vnet container
struct in oid_arg1.
In sysctl handlers dealing with virtualized sysctls, the
SYSCTL_RESOLVE_V_ARG1() macro will compute the address of the target
variable and make it available in arg1 variable for further processing.

Unused fields in structs vnet_inet, vnet_inet6 and vnet_ipfw have
been deleted.

Reviewed by:	bz, rwatson
Approved by:	julian (mentor)
2009-04-30 13:36:26 +00:00
Robert Watson
6064c5d362 Add ifunit_ref(), a version of ifunit(), that returns not just an
interface pointer, but also a reference to it.

Modify ifioctl() to use ifunit_ref(), holding the reference until
all ioctls, etc, have completed.

This closes a class of reader-writer races in which interfaces
could be removed during long-running ioctls, leading to crashes.
Many other consumers of ifunit() should now use ifunit_ref() to
avoid similar races.

MFC after:	3 weeks
2009-04-23 13:08:47 +00:00
Robert Watson
111c6b617b During if_detach(), invoke if_dead() to set the ifnet's function
pointers to "dead" implementations that no-op rather than invoking
the device driver.  This would generally be unexpected and
possibly quite badly handled by most device drivers after
if_detach() has completed.

Reviewed by:	bms
MFC after:	3 weeks
2009-04-23 11:51:53 +00:00
Robert Watson
27d37320ec Start to address a number of races relating to use of ifnet pointers
after the corresponding interface has been destroyed:

(1) Add an ifnet refcount, ifp->if_refcount.  Initialize it to 1 in
    if_alloc(), and modify if_free_type() to decrement and check the
    refcount.

(2) Add new if_ref() and if_rele() interfaces to allow kernel code
    walking global interface lists to release IFNET_[RW]LOCK() yet
    keep the ifnet stable.  Currently, if_rele() is a no-op wrapper
    around if_free(), but this may change in the future.

(3) Add new ifnet field, if_alloctype, which caches the type passed
    to if_alloc(), but unlike if_type, won't be changed by drivers.
    This allows asynchronous free's of the interface after the
    driver has released it to still use the right type.  Use that
    instead of the type passed to if_free_type(), but assert that
    they are the same (might have to rethink this if that doesn't
    work out).

(4) Add a new ifnet_byindex_ref(), which looks up an interface by
    index and returns a reference rather than a pointer to it.

(5) Fix if_alloc() to fully initialize the if_addr_mtx before hooking
    up the ifnet to global lists.

(6) Modify sysctls in if_mib.c to use ifnet_byindex_ref() and release
    the ifnet when done.

When this change is MFC'd, it will need to replace if_ispare fields
rather than adding new fields in order to avoid breaking the binary
interface.  Once this change is MFC'd, if_free_type() should be
removed, as its 'type' argument is now optional.

This refcount is not appropriate for counting mbuf pkthdr references,
and also not for counting entry into the device driver via ifnet
function pointers.  An rmlock may be appropriate for the latter.
Rather, this is about ensuring data structure stability when reaching
an ifnet via global ifnet lists and tables followed by copy in or out
of userspace.

MFC after:      3 weeks
Reported by:    mdtancsa
Reviewed by:    brooks
2009-04-21 22:43:32 +00:00
Kip Macy
7cc5b47fb3 export if_qflush for use by driver if_qflush routines
only set ifp->if_{transmit, qflush} if not already set
KASSERT that neither or both are set
2009-04-16 23:05:10 +00:00
Kip Macy
279aa3d419 Change if_output to take a struct route as its fourth argument in order
to allow passing a cached struct llentry * down to L2

Reviewed by:	rwatson
2009-04-16 20:30:28 +00:00
Kip Macy
3efea33724 Adapt buf_ring abstraction interface to allow consumers to interoperate with ALTQ 2009-04-14 00:27:59 +00:00
Robert Watson
e5adda3d51 Remove IFF_NEEDSGIANT, a compatibility infrastructure introduced
in FreeBSD 5.x to allow network device drivers to run with Giant
despite the network stack being Giant-free.  This significantly
simplifies calls into ioctl() on network interfaces, especially
in the multicast code, as well as eliminates deferred invocation
of interface if_start routines.

Disable the build on device drivers still depending on
IFF_NEEDSGIANT as they no longer compile.  They will be removed
in a few weeks if they haven't been made MPSAFE in that time.
Disabled drivers:

        if_ar
        if_axe
        if_aue
        if_cdce
        if_cue
        if_kue
        if_ray
        if_rue
        if_rum
        if_sr
        if_udav
        if_ural
        if_zyd

Drivers that were already disabled because of tty changes:

        if_ppp
        if_sl

Discussed on:	arch@
2009-03-15 14:21:05 +00:00
Robert Watson
3055e123d7 Do a bit of struct ifnet cleanup in preparation for 8.0: group function
pointers together, move padding to the bottom of the structure, and add
two new integer spares due to attrition over time.  Remove unused spare
"flags" field, we can use one of the spare ints if we need it later.

This change requires a rebuild of device driver modules that depend on
the layout of ifnet for binary compatibility reasons.

Discussed with:	kmacy
2009-03-01 12:42:54 +00:00
Kip Macy
64c44e5db8 Keep stats in drbr_enqueue
Discussed with: ps
2008-12-17 08:12:50 +00:00
Kip Macy
1635d9171c merge in 2 buf_ring helper routines for enqueueing and freeing buf_rings 2008-12-17 04:00:43 +00:00
Kip Macy
991f8615e4 convert ifnet and afdata locks from mutexes to rwlocks 2008-12-17 00:11:56 +00:00
Qing Li
6e6b3f7cbc This main goals of this project are:
1. separating L2 tables (ARP, NDP) from the L3 routing tables
2. removing as much locking dependencies among these layers as
   possible to allow for some parallelism in the search operations
3. simplify the logic in the routing code,

The most notable end result is the obsolescent of the route
cloning (RTF_CLONING) concept, which translated into code reduction
in both IPv4 ARP and IPv6 NDP related modules, and size reduction in
struct rtentry{}. The change in design obsoletes the semantics of
RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland
applications such as "arp" and "ndp" have been modified to reflect
those changes. The output from "netstat -r" shows only the routing
entries.

Quite a few developers have contributed to this project in the
past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and
Andre Oppermann. And most recently:

- Kip Macy revised the locking code completely, thus completing
  the last piece of the puzzle, Kip has also been conducting
  active functional testing
- Sam Leffler has helped me improving/refactoring the code, and
  provided valuable reviews
- Julian Elischer setup the perforce tree for me and has helped
  me maintaining that branch before the svn conversion
2008-12-15 06:10:57 +00:00
Bjoern A. Zeeb
1b193af610 Second round of putting global variables, which were virtualized
but formerly missed under VIMAGE_GLOBAL.

Put the extern declarations of the  virtualized globals
under VIMAGE_GLOBAL as the globals themsevles are already.
This will help by the time when we are going to remove the globals
entirely.

Sponsored by:	The FreeBSD Foundation
2008-12-13 19:13:03 +00:00
Bjoern A. Zeeb
4b79449e2f Rather than using hidden includes (with cicular dependencies),
directly include only the header files needed. This reduces the
unneeded spamming of various headers into lots of files.

For now, this leaves us with very few modules including vnet.h
and thus needing to depend on opt_route.h.

Reviewed by:	brooks, gnn, des, zec, imp
Sponsored by:	The FreeBSD Foundation
2008-12-02 21:37:28 +00:00
Kip Macy
db7f0b974f - bump __FreeBSD version to reflect added buf_ring, memory barriers,
and ifnet functions

- add memory barriers to <machine/atomic.h>
- update drivers to only conditionally define their own

- add lockless producer / consumer ring buffer
- remove ring buffer implementation from cxgb and update its callers

- add if_transmit(struct ifnet *ifp, struct mbuf *m) to ifnet to
  allow drivers to efficiently manage multiple hardware queues
  (i.e. not serialize all packets through one ifq)
- expose if_qflush to allow drivers to flush any driver managed queues

This work was supported by Bitgravity Inc. and Chelsio Inc.
2008-11-22 05:55:56 +00:00
Marko Zec
8b615593fc Step 1.5 of importing the network stack virtualization infrastructure
from the vimage project, as per plan established at devsummit 08/08:
http://wiki.freebsd.org/Image/Notes200808DevSummit

Introduce INIT_VNET_*() initializer macros, VNET_FOREACH() iterator
macros, and CURVNET_SET() context setting macros, all currently
resolving to NOPs.

Prepare for virtualization of selected SYSCTL objects by introducing a
family of SYSCTL_V_*() macros, currently resolving to their global
counterparts, i.e. SYSCTL_V_INT() == SYSCTL_INT().

Move selected #defines from sys/sys/vimage.h to newly introduced header
files specific to virtualized subsystems (sys/net/vnet.h,
sys/netinet/vinet.h etc.).

All the changes are verified to have zero functional impact at this
point in time by doing MD5 comparision between pre- and post-change
object files(*).

(*) netipsec/keysock.c did not validate depending on compile time options.

Implemented by:	julian, bz, brooks, zec
Reviewed by:	julian, bz, brooks, kris, rwatson, ...
Approved by:	julian (mentor)
Obtained from:	//depot/projects/vimage-commit2/...
X-MFC after:	never
Sponsored by:	NLnet Foundation, The FreeBSD Foundation
2008-10-02 15:37:58 +00:00
Andrew Thompson
516993d48e ifnet_setbyindex() is only used locally, go back to being static. 2008-08-20 05:00:18 +00:00
Kip Macy
1887d35f06 Fix build 2008-08-20 03:14:48 +00:00
Robert Watson
02f4879d3a Introduce locking around use of ifindex_table, whose use was previously
unsynchronized.  While races were extremely rare, we've now had a
couple of reports of panics in environments involving large numbers of
IPSEC tunnels being added very quickly on an active system.

- Add accessor functions ifnet_byindex(), ifaddr_byindex(),
  ifdev_byindex() to replace existing accessor macros.  These functions
  now acquire the ifnet lock before derefencing the table.
- Add IFNET_WLOCK_ASSERT().
- Add static accessor functions ifnet_setbyindex(), ifdev_setbyindex(),
  which set values in the table either asserting of acquiring the ifnet
  lock.
- Use accessor functions throughout if.c to modify and read
  ifindex_table.
- Rework ifnet attach/detach to lock around ifindex_table modification.

Note that these changes simply close races around use of ifindex_table,
and make no attempt to solve the probem of disappearing ifnets.  Further
refinement of this work, including with respect to ifindex_table
resizing, is still required.

In a future change, the ifnet lock should be converted from a mutex to an
rwlock in order to reduce contention.

Reviewed and tested by:	brooks
2008-06-26 23:05:28 +00:00
Julian Elischer
8b07e49a00 Add code to allow the system to handle multiple routing tables.
This particular implementation is designed to be fully backwards compatible
and to be MFC-able to 7.x (and 6.x)

Currently the only protocol that can make use of the multiple tables is IPv4
Similar functionality exists in OpenBSD and Linux.

From my notes:

-----

  One thing where FreeBSD has been falling behind, and which by chance I
  have some time to work on is "policy based routing", which allows
  different
  packet streams to be routed by more than just the destination address.

  Constraints:
  ------------

  I want to make some form of this available in the 6.x tree
  (and by extension 7.x) , but FreeBSD in general needs it so I might as
  well do it in -current and back port the portions I need.

  One of the ways that this can be done is to have the ability to
  instantiate multiple kernel routing tables (which I will now
  refer to as "Forwarding Information Bases" or "FIBs" for political
  correctness reasons). Which FIB a particular packet uses to make
  the next hop decision can be decided by a number of mechanisms.
  The policies these mechanisms implement are the "Policies" referred
  to in "Policy based routing".

  One of the constraints I have if I try to back port this work to
  6.x is that it must be implemented as a EXTENSION to the existing
  ABIs in 6.x so that third party applications do not need to be
  recompiled in timespan of the branch.

  This first version will not have some of the bells and whistles that
  will come with later versions. It will, for example, be limited to 16
  tables in the first commit.
  Implementation method, Compatible version. (part 1)
  -------------------------------
  For this reason I have implemented a "sufficient subset" of a
  multiple routing table solution in Perforce, and back-ported it
  to 6.x. (also in Perforce though not  always caught up with what I
  have done in -current/P4). The subset allows a number of FIBs
  to be defined at compile time (8 is sufficient for my purposes in 6.x)
  and implements the changes needed to allow IPV4 to use them. I have not
  done the changes for ipv6 simply because I do not need it, and I do not
  have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it.

  Other protocol families are left untouched and should there be
  users with proprietary protocol families, they should continue to work
  and be oblivious to the existence of the extra FIBs.

  To understand how this is done, one must know that the current FIB
  code starts everything off with a single dimensional array of
  pointers to FIB head structures (One per protocol family), each of
  which in turn points to the trie of routes available to that family.

  The basic change in the ABI compatible version of the change is to
  extent that array to be a 2 dimensional array, so that
  instead of protocol family X looking at rt_tables[X] for the
  table it needs, it looks at rt_tables[Y][X] when for all
  protocol families except ipv4 Y is always 0.
  Code that is unaware of the change always just sees the first row
  of the table, which of course looks just like the one dimensional
  array that existed before.

  The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign()
  are all maintained, but refer only to the first row of the array,
  so that existing callers in proprietary protocols can continue to
  do the "right thing".
  Some new entry points are added, for the exclusive use of ipv4 code
  called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(),
  which have an extra argument which refers the code to the correct row.

  In addition, there are some new entry points (currently called
  rtalloc_fib() and friends) that check the Address family being
  looked up and call either rtalloc() (and friends) if the protocol
  is not IPv4 forcing the action to row 0 or to the appropriate row
  if it IS IPv4 (and that info is available). These are for calling
  from code that is not specific to any particular protocol. The way
  these are implemented would change in the non ABI preserving code
  to be added later.

  One feature of the first version of the code is that for ipv4,
  the interface routes show up automatically on all the FIBs, so
  that no matter what FIB you select you always have the basic
  direct attached hosts available to you. (rtinit() does this
  automatically).

  You CAN delete an interface route from one FIB should you want
  to but by default it's there. ARP information is also available
  in each FIB. It's assumed that the same machine would have the
  same MAC address, regardless of which FIB you are using to get
  to it.

  This brings us as to how the correct FIB is selected for an outgoing
  IPV4 packet.

  Firstly, all packets have a FIB associated with them. if nothing
  has been done to change it, it will be FIB 0. The FIB is changed
  in the following ways.

  Packets fall into one of a number of classes.

  1/ locally generated packets, coming from a socket/PCB.
     Such packets select a FIB from a number associated with the
     socket/PCB. This in turn is inherited from the process,
     but can be changed by a socket option. The process in turn
     inherits it on fork. I have written a utility call setfib
     that acts a bit like nice..

         setfib -3 ping target.example.com # will use fib 3 for ping.

     It is an obvious extension to make it a property of a jail
     but I have not done so. It can be achieved by combining the setfib and
     jail commands.

  2/ packets received on an interface for forwarding.
     By default these packets would use table 0,
     (or possibly a number settable in a sysctl(not yet)).
     but prior to routing the firewall can inspect them (see below).
     (possibly in the future you may be able to associate a FIB
     with packets received on an interface..  An ifconfig arg, but not yet.)

  3/ packets inspected by a packet classifier, which can arbitrarily
     associate a fib with it on a packet by packet basis.
     A fib assigned to a packet by a packet classifier
     (such as ipfw) would over-ride a fib associated by
     a more default source. (such as cases 1 or 2).

  4/ a tcp listen socket associated with a fib will generate
     accept sockets that are associated with that same fib.

  5/ Packets generated in response to some other packet (e.g. reset
     or icmp packets). These should use the FIB associated with the
     packet being reponded to.

  6/ Packets generated during encapsulation.
     gif, tun and other tunnel interfaces will encapsulate using the FIB
     that was in effect withthe proces that set up the tunnel.
     thus setfib 1 ifconfig gif0 [tunnel instructions]
     will set the fib for the tunnel to use to be fib 1.

  Routing messages would be associated with their
  process, and thus select one FIB or another.
  messages from the kernel would be associated with the fib they
  refer to and would only be received by a routing socket associated
  with that fib. (not yet implemented)

  In addition Netstat has been edited to be able to cope with the
  fact that the array is now 2 dimensional. (It looks in system
  memory using libkvm (!)). Old versions of netstat see only the first FIB.

  In addition two sysctls are added to give:
  a) the number of FIBs compiled in (active)
  b) the default FIB of the calling process.

  Early testing experience:
  -------------------------

  Basically our (IronPort's) appliance does this functionality already
  using ipfw fwd but that method has some drawbacks.

  For example,
  It can't fully simulate a routing table because it can't influence the
  socket's choice of local address when a connect() is done.

  Testing during the generating of these changes has been
  remarkably smooth so far. Multiple tables have co-existed
  with no notable side effects, and packets have been routes
  accordingly.

  ipfw has grown 2 new keywords:

  setfib N ip from anay to any
  count ip from any to any fib N

  In pf there seems to be a requirement to be able to give symbolic names to the
  fibs but I do not have that capacity. I am not sure if it is required.

  SCTP has interestingly enough built in support for this, called VRFs
  in Cisco parlance. it will be interesting to see how that handles it
  when it suddenly actually does something.

  Where to next:
  --------------------

  After committing the ABI compatible version and MFCing it, I'd
  like to proceed in a forward direction in -current. this will
  result in some roto-tilling in the routing code.

  Firstly: the current code's idea of having a separate tree per
  protocol family, all of the same format, and pointed to by the
  1 dimensional array is a bit silly. Especially when one considers that
  there is code that makes assumptions about every protocol having the
  same internal structures there. Some protocols don't WANT that
  sort of structure. (for example the whole idea of a netmask is foreign
  to appletalk). This needs to be made opaque to the external code.

  My suggested first change is to add routing method pointers to the
  'domain' structure, along with information pointing the data.
  instead of having an array of pointers to uniform structures,
  there would be an array pointing to the 'domain' structures
  for each protocol address domain (protocol family),
  and the methods this reached would be called. The methods would have
  an argument that gives FIB number, but the protocol would be free
  to ignore it.

  When the ABI can be changed it raises the possibilty of the
  addition of a fib entry into the "struct route". Currently,
  the structure contains the sockaddr of the desination, and the resulting
  fib entry. To make this work fully, one could add a fib number
  so that given an address and a fib, one can find the third element, the
  fib entry.

  Interaction with the ARP layer/ LL layer would need to be
  revisited as well. Qing Li has been working on this already.

  This work was sponsored by Ironport Systems/Cisco

Reviewed by:    several including rwatson, bz and mlair (parts each)
Obtained from:  Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
Sam Leffler
fb27dd1db3 expose if_purgemaddrs, it will be used by the vap code unless someone
redesigns the mcast support code in the next few weeks

MFC after:	3 weeks
2008-03-25 21:23:32 +00:00
Kip Macy
2de2af32a0 Add padding for anticipated functionality
- vimage
 - TOE
 - multiq
 - host rtentry caching

Rename spare used by 80211 to if_llsoftc

Reviewed by: rwatson, gnn
MFC after: 1 day
2007-12-07 01:46:13 +00:00
Brooks Davis
bec59525e6 The struct if_data members ifi_recvquota and ifi_xmitquota have been
unused for ages.  Rename them to ifi_spare_char1 and ifi_spare_char2
respectively to indicate this face.
2007-05-16 18:37:37 +00:00
Andrew Thompson
18242d3b09 Rename the trunk(4) driver to lagg(4) as it is too similar to vlan trunking.
The name trunk is misused as the networking term trunk means carrying multiple
VLANs over a single connection. The IEEE standard for link aggregation (802.3
section 3) does not talk about 'trunk' at all while it is used throughout IEEE
802.1Q in describing vlans.

The lagg(4) driver provides link aggregation, failover and fault tolerance.

Discussed on:	current@
2007-04-17 00:35:11 +00:00
Andrew Thompson
b47888ceba Add the trunk(4) driver for providing link aggregation, failover and fault
tolerance.  This driver allows aggregation of multiple network interfaces as
one virtual interface using a number of different protocols/algorithms.

failover    - Sends traffic through the secondary port if the master becomes
              inactive.
fec         - Supports Cisco Fast EtherChannel.
lacp        - Supports the IEEE 802.3ad Link Aggregation Control Protocol
              (LACP) and the Marker Protocol.
loadbalance - Static loadbalancing using an outgoing hash.
roundrobin  - Distributes outgoing traffic using a round-robin scheduler
              through all active ports.

This code was obtained from OpenBSD and this also includes 802.3ad LACP support
from agr(4) in NetBSD.
2007-04-10 00:27:25 +00:00
Bruce M Simpson
5896d12465 Fix tinderbox; ng_ether needs to see if_findmulti(). 2007-03-20 03:15:43 +00:00
Bruce M Simpson
ec002fee99 Implement reference counting for ifmultiaddr, in_multi, and in6_multi
structures. Detect when ifnet instances are detached from the network
stack and perform appropriate cleanup to prevent memory leaks.

This has been implemented in such a way as to be backwards ABI compatible.
Kernel consumers are changed to use if_delmulti_ifma(); in_delmulti()
is unable to detect interface removal by design, as it performs searches
on structures which are removed with the interface.

With this architectural change, the panics FreeBSD users have experienced
with carp and pfsync should be resolved.

Obtained from:	p4 branch bms_netdev
Reviewed by:	andre
Sponsored by:	Garance A Drosehn
Idea from:	NetBSD
MFC after:	1 month
2007-03-20 00:36:10 +00:00
Andre Oppermann
60d4ab7abb Improve description of if_capabilities, if_capenable and ifi_hwassist.
Sponsored by:	TCP/IP Optimization Fundraise 2005
2006-09-06 18:06:04 +00:00
Andre Oppermann
773725a255 Fix the socket option IP_ONESBCAST by giving it its own case in ip_output()
and skip over the normal IP processing.

Add a supporting function ifa_ifwithbroadaddr() to verify and validate the
supplied subnet broadcast address.

PR:		kern/99558
Tested by:	Andrey V. Elsukov <bu7cher-at-yandex.ru>
Sponsored by:	TCP/IP Optimization Fundraise 2005
MFC after:	3 days
2006-09-06 17:12:10 +00:00