Commit Graph

95 Commits

Author SHA1 Message Date
knakahara 45ca136d96 gif(4), ipsec(4) and l2tp(4) use encap_attach_addr(). 2022-12-07 08:30:15 +00:00
knakahara 70414ea5b8 Add sysctl nodes to control fragmentation with IPv[46] over IPv6 gif(4).
New sysctl node "net.inet6.ip6.gifpmtu" means
    - 0 (default)
      Fragment by IPV6_MMTU. All packets reach the destination certainly,
      however the long packet performance is poor.
      This is same behavior as before.
    - 1
      Fragment by outer interface's MTU. The long packet performance would
      be good, however the packets may be dropped in some network paths
      whose path MTU less than the interface's MTU.
    - others
      undefined yet

New sysctl node "net.interfaces.gif*.pmtu" means
    - -1 (default)
      Use system default value (net.inet6.ip6.gifpmtu).
    - 0
      Fragment by IPV6_MMTU for this gif(4) tunnel.
    - 1
      Fragment by outer interface's MTU for this gif(4) tunnel.
    - others
      undefined yet

See RFC4459 for more information and other solutions.
2019-10-30 03:45:59 +00:00
knakahara 2da350beca Avoid having a rtcache directly in a percpu storage for tunnel protocols.
percpu(9) has a certain memory storage for each CPU and provides it by the piece
to users.  If the storages went short, percpu(9) enlarges them by allocating new
larger memory areas, replacing old ones with them and destroying the old ones.
A percpu storage referenced by a pointer gotten via percpu_getref can be
destroyed by the mechanism after a running thread sleeps even if percpu_putref
has not been called.

Using rtcache, i.e., packet processing, typically involves sleepable operations
such as rwlock so we must avoid dereferencing a rtcache that is directly stored
in a percpu storage during packet processing.  Address this situation by having
just a pointer to a rtcache in a percpu storage instead.

Reviewed by ozaki-r@ and yamaguchi@
2019-09-19 06:07:24 +00:00
maxv 86ac125b49 Remove now unused net_osdep.h includes, the other BSDs did the same. 2018-05-01 07:21:39 +00:00
knakahara b0c61d654b Fix LOCKDEBUG kernel panic when many(about 200) tunnel interfaces is created.
The tunnel interfaces are gif(4), l2tp(4), and ipsecif(4). They use mutex
itself in percpu area. When percpu_cpu_enlarge() run, the address of the
mutex in percpu area becomes different from the address which lockdebug
saved. That can cause "already initialized" false detection.
2018-04-27 09:55:27 +00:00
knakahara 38db08c668 Fix error checking in in6_gif_ctlinput().
if_gif.c:r1.133 introduces gif_update_variant() which ensure ifp->if_flags
is set IFF_RUNNING when gif_softc->gif_var->gv_{psrc,pdst} are not null.
So, in6_gif_ctlinput() is not required IFF_RUNNING checking. In contrast,
it is required gv_{psrc,pdst} NULL checking.
2018-03-14 07:56:32 +00:00
knakahara fe5d98860a apply in{,6}_tunnel_validate() to gif(4). 2018-01-10 11:13:26 +00:00
knakahara 753ed3406c IFF_RUNNING checking in Rx and Tx processing is unnecessary now.
Because the configs of gif (members of gif_var) are protected by psref(9).
2017-11-27 05:05:50 +00:00
knakahara 493e35e35d preserve gif(4) configs by psref(9) like vlan(4) and l2tp(4).
After Tx side does not use softint, gif(4) can use psref(9) for config
preservation like vlan(4) and l2tp(4).

update locking notes later.
2017-11-27 05:02:22 +00:00
knakahara fb23bb2cff Add argument to encapsw->pr_input() instead of m_tag. 2017-11-15 10:42:41 +00:00
knakahara 56188c2a5a add lock for percpu route like l2tp(4). 2017-09-21 09:42:03 +00:00
christos 35561f6b22 ip6_sprintf -> IN6_PRINT so that we pass the size. 2017-01-16 15:44:46 +00:00
ryo 28f4c24cc2 Make ip6_sprintf(), in_fmtaddr(), lla_snprintf() and icmp6_redirect_diag() mpsafe.
Reviewed by ozaki-r@
2017-01-16 07:33:36 +00:00
knakahara cc189cdb90 remove unnecessary conversion.
gif_softc->gif_pdst is already valid sockaddr.
2017-01-06 03:25:13 +00:00
knakahara 237f476937 fix race of gif_softc->gif_ro when we send multiple flows over gif on NET_MPSAFE enabled kernel.
make gif_softc->gif_ro percpu as well as ipforward_rt to resolve this race.
and add future TODO comment for etherip(4).
2016-12-14 11:19:15 +00:00
ozaki-r 6fb8880601 Make the routing table and rtcaches MP-safe
See the following descriptions for details.

Proposed on tech-kern and tech-net


Overview
--------

We protect the routing table with a rwock and protect
rtcaches with another rwlock. Each rtentry is protected
from being freed or updated via reference counting and psref.

Global rwlocks
--------------

There are two rwlocks; one for the routing table (rt_lock) and
the other for rtcaches (rtcache_lock). rtcache_lock covers
all existing rtcaches; there may have room for optimizations
(future work).

The locking order is rtcache_lock first and rt_lock is next.

rtentry references
------------------

References to an rtentry is managed with reference counting
and psref. Either of the two mechanisms is used depending on
where a rtentry is obtained. Reference counting is used when
we obtain a rtentry from the routing table directly via
rtalloc1 and rtrequest{,1} while psref is used when we obtain
a rtentry from a rtcache via rtcache_* APIs. In both cases,
a caller can sleep/block with holding an obtained rtentry.

The reasons why we use two different mechanisms are (i) only
using reference counting hurts the performance due to atomic
instructions (rtcache case) (ii) ease of implementation;
applying psref to APIs such rtaloc1 and rtrequest{,1} requires
additional works (adding a local variable and an argument).

We will finally migrate to use only psref but we can do it
when we have a lockless routing table alternative.

Reference counting for rtentry
------------------------------

rt_refcnt now doesn't count permanent references such as for
rt_timers and rtcaches, instead it is used only for temporal
references when obtaining a rtentry via rtalloc1 and rtrequest{,1}.
We can do so because destroying a rtentry always involves
removing references of rt_timers and rtcaches to the rtentry
and we don't need to track such references. This also makes
it easy to wait for readers to release references on deleting
or updating a rtentry, i.e., we can simply wait until the
reference counter is 0 or 1. (If there are permanent references
the counter can be arbitrary.)

rt_ref increments a reference counter of a rtentry and rt_unref
decrements it. rt_ref is called inside APIs (rtalloc1 and
rtrequest{,1} so users don't need to care about it while
users must call rt_unref to an obtained rtentry after using it.

rtfree is removed and we use rt_unref and rt_free instead.
rt_unref now just decrements the counter of a given rtentry
and rt_free just tries to destroy a given rtentry.

See the next section for destructions of rtentries by rt_free.

Destructions of rtentries
-------------------------

We destroy a rtentry only when we call rtrequst{,1}(RTM_DELETE);
the original implementation can destroy in any rtfree where it's
the last reference. If we use reference counting or psref, it's
easy to understand if the place that a rtentry is destroyed is
fixed.

rt_free waits for references to a given rtentry to be released
before actually destroying the rtentry. rt_free uses a condition
variable (cv_wait) (and psref_target_destroy for psref) to wait.

Unfortunately rtrequst{,1}(RTM_DELETE) can be called in softint
that we cannot use cv_wait. In that case, we have to defer the
destruction to a workqueue.

rtentry#rt_cv, rtentry#rt_psref and global variables
(see rt_free_global) are added to conduct the procedure.

Updates of rtentries
--------------------

One difficulty to use refcnt/psref instead of rwlock for rtentry
is updates of rtentries. We need an additional mechanism to
prevent readers from seeing inconsistency of a rtentry being
updated.

We introduce RTF_UPDATING flag to rtentries that are updating.
While the flag is set to a rtentry, users cannot acquire the
rtentry. By doing so, we avoid users to see inconsistent
rtentries.

There are two options when a user tries to acquire a rtentry
with the RTF_UPDATING flag; if a user runs in softint context
the user fails to acquire a rtentry (NULL is returned).
Otherwise a user waits until the update completes by waiting
on cv.

The procedure of a updater is simpler to destruction of
a rtentry. Wait on cv (and psref) and after all readers left,
proceed with the update.

Global variables (see rt_update_global) are added to conduct
the procedure.

Currently we apply the mechanism to only RTM_CHANGE in
rtsock.c. We would have to apply other codes. See
"Known issues" section.

psref for rtentry
-----------------

When we obtain a rtentry from a rtcache via rtcache_* APIs,
psref is used to reference to the rtentry.

rtcache_ref acquires a reference to a rtentry with psref
and rtcache_unref releases the reference after using it.
rtcache_ref is called inside rtcache_* APIs and users don't
need to take care of it while users must call rtcache_unref
to release the reference.

struct psref and int bound that is needed for psref is
embedded into struct route. By doing so we don't need to
add local variables and additional argument to APIs.

However this adds another constraint to psref other than
reference counting one's; holding a reference of an rtentry
via a rtcache is allowed by just one caller at the same time.
So we must not acquire a rtentry via a rtcache twice and
avoid a recursive use of a rtcache. And also a rtcache must
be arranged to be used by a LWP/softint at the same time
somehow. For IP forwarding case, we have per-CPU rtcaches
used in softint so the constraint is guaranteed. For a h
rtcache of a PCB case, the constraint is guaranteed by the
solock of each PCB. Any other cases (pf, ipf, stf and ipsec)
are currently guaranteed by only the existence of the global
locks (softnet_lock and/or KERNEL_LOCK). If we've found the
cases that we cannot guarantee the constraint, we would need
to introduce other rtcache APIs that use simple reference
counting.

psref of rtcache is created with IPL_SOFTNET and so rtcache
shouldn't used at an IPL higher than IPL_SOFTNET.

Note that rtcache_free is used to invalidate a given rtcache.
We don't need another care by my change; just keep them as
they are.

Performance impact
------------------

When NET_MPSAFE is disabled the performance drop is 3% while
when it's enabled the drop is increased to 11%. The difference
comes from that currently we don't take any global locks and
don't use psref if NET_MPSAFE is disabled.

We can optimize the performance of the case of NET_MPSAFE
on by reducing lookups of rtcache that uses psref;
currently we do two lookups but we should be able to trim
one of two. This is a future work.

Known issues
------------

There are two known issues to be solved; one is that
a caller of rtrequest(RTM_ADD) may change rtentry (see rtinit).
We need to prevent new references during the update. Or
we may be able to remove the code (perhaps, need more
investigations).

The other is rtredirect that updates a rtentry. We need
to apply our update mechanism, however it's not easy because
rtredirect is called in softint and we cannot apply our
mechanism simply. One solution is to defer rtredirect to
a workqueue but it requires some code restructuring.
2016-12-12 03:55:57 +00:00
ozaki-r 4c25fb2f83 Add rtcache_unref to release points of rtentry stemming from rtcache
In the MP-safe world, a rtentry stemming from a rtcache can be freed at any
points. So we need to protect rtentries somehow say by reference couting or
passive references. Regardless of the method, we need to call some release
function of a rtentry after using it.

The change adds a new function rtcache_unref to release a rtentry. At this
point, this function does nothing because for now we don't add a reference
to a rtentry when we get one from a rtcache. We will add something useful
in a further commit.

This change is a part of changes for MP-safe routing table. It is separated
to avoid one big change that makes difficult to debug by bisecting.
2016-12-08 05:16:33 +00:00
ozaki-r 8759207c83 Use sin6tosa and sin6tocsa macros
No functional change.
2016-07-15 07:40:09 +00:00
ozaki-r d04ff44ad6 Apply m_get_rcvif_psref (kill m_get_rcvif_NOMPSAFE) 2016-07-06 00:30:55 +00:00
knakahara a6d7586724 fix: gif(4) receive side race
A panic cause in rn_match() called by encap[46]_lookup(). The reason is that
gif(4) does not suspend receive packet processing in spite of suspending
transmit packet processing while anyone is doing gif(4) ioctl.
2016-07-04 04:22:47 +00:00
knakahara d81cd78ed7 let gif(4) promise softint(9) contract (1/2) : gif(4) side
To prevent calling softint_schedule() after called softint_disestablish(),
the following modifications are added
    + ioctl (writing configuration) side
      - off IFF_RUNNING flag before changing configuration
      - wait softint handler completion before changing configuration
    + packet processing (reading configuraiotn) side
      - if IFF_RUNNING flag is on, do nothing
    + in whole
      - add gif_list_lock_{enter,exit} to prevent the same configuration is
        set to other gif(4) interfaces
2016-07-04 04:14:47 +00:00
ozaki-r ca4ea29d93 Add missing NULL checks for m_get_rcvif_psref 2016-06-28 02:02:56 +00:00
ozaki-r fe6d427551 Avoid storing a pointer of an interface in a mbuf
Having a pointer of an interface in a mbuf isn't safe if we remove big
kernel locks; an interface object (ifnet) can be destroyed anytime in any
packet processing and accessing such object via a pointer is racy. Instead
we have to get an object from the interface collection (ifindex2ifnet) via
an interface index (if_index) that is stored to a mbuf instead of an
pointer.

The change provides two APIs: m_{get,put}_rcvif_psref that use psref(9)
for sleep-able critical sections and m_{get,put}_rcvif that use
pserialize(9) for other critical sections. The change also adds another
API called m_get_rcvif_NOMPSAFE, that is NOT MP-safe and for transition
moratorium, i.e., it is intended to be used for places where are not
planned to be MP-ified soon.

The change adds some overhead due to psref to performance sensitive paths,
however the overhead is not serious, 2% down at worst.

Proposed on tech-kern and tech-net.
2016-06-10 13:31:43 +00:00
knakahara 9b7918b3ee remove unnecessary declarations and fix KNF
Thanks to riastradh@
2016-02-29 01:29:15 +00:00
knakahara e80f101289 To eliminate gif_softc_list linear search, add extra argument to encapsw.pr_ctlinput(). 2016-02-26 07:35:17 +00:00
knakahara b546d5277b implement encapsw instead of protosw and uniform prototype.
suggested and advised by riastradh@n.o, thanks.

BTW, It seems in_stf_input() had bugs...
2016-01-26 05:58:05 +00:00
riastradh fa50b451d4 Those were local changes not meant to be part of the revert. SORRY! 2016-01-23 14:48:55 +00:00
christos e28df70b14 make this compile again 2016-01-23 14:03:04 +00:00
riastradh e588d95c25 Back out previous change to introduce struct encapsw.
This change was intended, but Nakahara-san had already made a better
one locally!  So I'll let him commit that one, and I'll try not to
step on anyone's toes again.
2016-01-22 23:27:12 +00:00
riastradh 87bc652e3d Don't abuse struct protosw for ip_encap -- introduce struct encapsw.
Mostly mechanical change to replace it, culling some now-needless
boilerplate around all the users.

This does not substantively change the ip_encap API or eliminate
abuse of sketchy pointer casts -- that will come later, and will be
easier now that it is not tangled up with struct protosw.
2016-01-22 05:15:10 +00:00
riastradh 65a8f527af Eliminate struct protosw::pr_output.
You can't use this unless you know what it is a priori: the formal
prototype is variadic, and the different instances (e.g., ip_output,
route_output) have different real prototypes.

Convert the only user of it, raw_send in net/raw_cb.c, to take an
explicit callback argument.  Convert the only instances of it,
route_output and key_output, to such explicit callbacks for raw_send.
Use assertions to make sure the conversion to explicit callbacks is
warranted.

Discussed on tech-net with no objections:
https://mail-index.netbsd.org/tech-net/2016/01/16/msg005484.html
2016-01-20 21:43:59 +00:00
knakahara d7b9bb29c0 Refactor protosw codes in gif(4). No functional change.
- remove unnecessary include
    - reduce scopes
2016-01-18 06:08:26 +00:00
knakahara 6d50f36d54 use satosin{,6} macros instead of casts. 2015-12-25 06:47:56 +00:00
knakahara a00e94f4ff PR kern/50522: gif(4) ioctl causes panic while someone is using the gif(4) interface.
It is required to wait other CPU's softint completion before disestablishing
the softint handler.
2015-12-11 07:59:14 +00:00
pooka 1c4a50f192 sprinkle _KERNEL_OPT 2015-08-24 22:21:26 +00:00
ozaki-r 7600c4ec42 Add missing rtcache_free
It's the same as other similar code paths in in_gif and ip6_etherip.
2015-04-24 07:51:43 +00:00
rmind 39bd8dee77 Add struct pr_usrreqs with a pr_generic function and prepare for the
dismantling of pr_usrreq in the protocols; no functional change intended.
PRU_ATTACH/PRU_DETACH changes will follow soon.

Bump for struct protosw.  Welcome to 6.99.62!
2014-05-18 14:46:15 +00:00
joerg e240adbd0b Retire OSI network stack. OK core@ 2013-03-01 18:25:13 +00:00
dsl 02cdf4d2c8 Remove all the __P() from sys (excluding sys/dist)
Diff checked with grep and MK1 eyeball.
i386 and amd64 GENERIC and sys still build.
2009-03-14 14:45:51 +00:00
dyoung de87fe677d *** Summary ***
When a link-layer address changes (e.g., ifconfig ex0 link
02🇩🇪ad:be:ef:02 active), send a gratuitous ARP and/or a Neighbor
Advertisement to update the network-/link-layer address bindings
on our LAN peers.

Refuse a change of ethernet address to the address 00:00:00:00:00:00
or to any multicast/broadcast address.  (Thanks matt@.)

Reorder ifnet ioctl operations so that driver ioctls may inherit
the functions of their "class"---ether_ioctl(), fddi_ioctl(), et
cetera---and the class ioctls may inherit from the generic ioctl,
ifioctl_common(), but both driver- and class-ioctls may override
the generic behavior.  Make network drivers share more code.

Distinguish a "factory" link-layer address from others for the
purposes of both protecting that address from deletion and computing
EUI64.

Return consistent, appropriate error codes from network drivers.

Improve readability.  KNF.

*** Details ***

In if_attach(), always initialize the interface ioctl routine,
ifnet->if_ioctl, if the driver has not already initialized it.
Delete if_ioctl == NULL tests everywhere else, because it cannot
happen.

In the ioctl routines of network interfaces, inherit common ioctl
behaviors by calling either ifioctl_common() or whichever ioctl
routine is appropriate for the class of interface---e.g., ether_ioctl()
for ethernets.

Stop (ab)using SIOCSIFADDR and start to use SIOCINITIFADDR.  In
the user->kernel interface, SIOCSIFADDR's argument was an ifreq,
but on the protocol->ifnet interface, SIOCSIFADDR's argument was
an ifaddr.  That was confusing, and it would work against me as I
make it possible for a network interface to overload most ioctls.
On the protocol->ifnet interface, replace SIOCSIFADDR with
SIOCINITIFADDR.  In ifioctl(), return EPERM if userland tries to
invoke SIOCINITIFADDR.

In ifioctl(), give the interface the first shot at handling most
interface ioctls, and give the protocol the second shot, instead
of the other way around. Finally, let compatibility code (COMPAT_OSOCK)
take a shot.

Pull device initialization out of switch statements under
SIOCINITIFADDR.  For example, pull ..._init() out of any switch
statement that looks like this:

        switch (...->sa_family) {
        case ...:
                ..._init();
                ...
                break;
        ...
        default:
                ..._init();
                ...
                break;
        }

Rewrite many if-else clauses that handle all permutations of IFF_UP
and IFF_RUNNING to use a switch statement,

        switch (x & (IFF_UP|IFF_RUNNING)) {
        case 0:
                ...
                break;
        case IFF_RUNNING:
                ...
                break;
        case IFF_UP:
                ...
                break;
        case IFF_UP|IFF_RUNNING:
                ...
                break;
        }

unifdef lots of code containing #ifdef FreeBSD, #ifdef NetBSD, and
#ifdef SIOCSIFMTU, especially in fwip(4) and in ndis(4).

In ipw(4), remove an if_set_sadl() call that is out of place.

In nfe(4), reuse the jumbo MTU logic in ether_ioctl().

Let ethernets register a callback for setting h/w state such as
promiscuous mode and the multicast filter in accord with a change
in the if_flags: ether_set_ifflags_cb() registers a callback that
returns ENETRESET if the caller should reset the ethernet by calling
if_init(), 0 on success, != 0 on failure.  Pull common code from
ex(4), gem(4), nfe(4), sip(4), tlp(4), vge(4) into ether_ioctl(),
and register if_flags callbacks for those drivers.

Return ENOTTY instead of EINVAL for inappropriate ioctls.  In
zyd(4), use ENXIO instead of ENOTTY to indicate that the device is
not any longer attached.

Add to if_set_sadl() a boolean 'factory' argument that indicates
whether a link-layer address was assigned by the factory or some
other source.  In a comment, recommend using the factory address
for generating an EUI64, and update in6_get_hw_ifid() to prefer a
factory address to any other link-layer address.

Add a routing message, RTM_LLINFO_UPD, that tells protocols to
update the binding of network-layer addresses to link-layer addresses.
Implement this message in IPv4 and IPv6 by sending a gratuitous
ARP or a neighbor advertisement, respectively.  Generate RTM_LLINFO_UPD
messages on a change of an interface's link-layer address.

In ether_ioctl(), do not let SIOCALIFADDR set a link-layer address
that is broadcast/multicast or equal to 00:00:00:00:00:00.

Make ether_ioctl() call ifioctl_common() to handle ioctls that it
does not understand.

In gif(4), initialize if_softc and use it, instead of assuming that
the gif_softc and ifp overlap.

Let ifioctl_common() handle SIOCGIFADDR.

Sprinkle rtcache_invariants(), which checks on DIAGNOSTIC kernels
that certain invariants on a struct route are satisfied.

In agr(4), rewrite agr_ioctl_filter() to be a bit more explicit
about the ioctls that we do not allow on an agr(4) member interface.

bzero -> memset.  Delete unnecessary casts to void *.  Use
sockaddr_in_init() and sockaddr_in6_init().  Compare pointers with
NULL instead of "testing truth".  Replace some instances of (type
*)0 with NULL.  Change some K&R prototypes to ANSI C, and join
lines.
2008-11-07 00:20:01 +00:00
ad 15e29e981b Merge the socket locking patch:
- Socket layer becomes MP safe.
- Unix protocols become MP safe.
- Allows protocol processing interrupts to safely block on locks.
- Fixes a number of race conditions.

With much feedback from matt@ and plunky@.
2008-04-24 11:38:36 +00:00
thorpej 0dd41b37de Make ip6 and icmp6 stats per-cpu. 2008-04-15 03:57:04 +00:00
thorpej 3f466bce48 Change IPv6 stats from a structure to an array of uint64_t's.
Note: This is ABI-compatible with the old ip6stat structure; old netstat
binaries will continue to work properly.
2008-04-08 23:37:43 +00:00
dyoung 72fa642a86 Poison struct route->ro_rt uses in the kernel by changing the name
to _ro_rt.  Use rtcache_getrt() to access a route cache's struct
rtentry *.

Introduce struct ifnet->if_dl that always points at the interface
identifier/link-layer address.  Make code that treated the first
ifaddr on struct ifnet->if_addrlist as the interface address use
if_dl, instead.

Remove stale debugging code from net/route.c.  Move the rtflush()
code into rtcache_clear() and delete rtflush().  Delete rtalloc(),
because nothing uses it any more.

Make ND6_HINT an inline, lowercase subroutine, nd6_hint.

I've done my best to convert IP Filter, the ISO stack, and the
AppleTalk stack to rtcache_getrt().  They compile, but I have not
tested them.  I have given the changes to PF, GRE, IPv4 and IPv6
stacks a lot of exercise.
2007-12-20 19:53:29 +00:00
christos 72cfe7327b Ansify + add a few comments, from Karl Sjödahl 2007-05-23 17:14:59 +00:00
dyoung 72f0a6dfb0 Eliminate address family-specific route caches (struct route, struct
route_in6, struct route_iso), replacing all caches with a struct
route.

The principle benefit of this change is that all of the protocol
families can benefit from route cache-invalidation, which is
necessary for correct routing.  Route-cache invalidation fixes an
ancient PR, kern/3508, at long last; it fixes various other PRs,
also.

Discussions with and ideas from Joerg Sonnenberger influenced this
work tremendously.  Of course, all design oversights and bugs are
mine.

DETAILS

1 I added to each address family a pool of sockaddrs.  I have
  introduced routines for allocating, copying, and duplicating,
  and freeing sockaddrs:

        struct sockaddr *sockaddr_alloc(sa_family_t af, int flags);
        struct sockaddr *sockaddr_copy(struct sockaddr *dst,
                                       const struct sockaddr *src);
        struct sockaddr *sockaddr_dup(const struct sockaddr *src, int flags);
        void sockaddr_free(struct sockaddr *sa);

  sockaddr_alloc() returns either a sockaddr from the pool belonging
  to the specified family, or NULL if the pool is exhausted.  The
  returned sockaddr has the right size for that family; sa_family
  and sa_len fields are initialized to the family and sockaddr
  length---e.g., sa_family = AF_INET and sa_len = sizeof(struct
  sockaddr_in).  sockaddr_free() puts the given sockaddr back into
  its family's pool.

  sockaddr_dup() and sockaddr_copy() work analogously to strdup()
  and strcpy(), respectively.  sockaddr_copy() KASSERTs that the
  family of the destination and source sockaddrs are alike.

  The 'flags' argumet for sockaddr_alloc() and sockaddr_dup() is
  passed directly to pool_get(9).

2 I added routines for initializing sockaddrs in each address
  family, sockaddr_in_init(), sockaddr_in6_init(), sockaddr_iso_init(),
  etc.  They are fairly self-explanatory.

3 structs route_in6 and route_iso are no more.  All protocol families
  use struct route.  I have changed the route cache, 'struct route',
  so that it does not contain storage space for a sockaddr.  Instead,
  struct route points to a sockaddr coming from the pool the sockaddr
  belongs to.  I added a new method to struct route, rtcache_setdst(),
  for setting the cache destination:

        int rtcache_setdst(struct route *, const struct sockaddr *);

  rtcache_setdst() returns 0 on success, or ENOMEM if no memory is
  available to create the sockaddr storage.

  It is now possible for rtcache_getdst() to return NULL if, say,
  rtcache_setdst() failed.  I check the return value for NULL
  everywhere in the kernel.

4 Each routing domain (struct domain) has a list of live route
  caches, dom_rtcache.  rtflushall(sa_family_t af) looks up the
  domain indicated by 'af', walks the domain's list of route caches
  and invalidates each one.
2007-05-02 20:40:22 +00:00
christos 53524e44ef Kill caddr_t; there will be some MI fallout, but it will be fixed shortly. 2007-03-04 05:59:00 +00:00
dyoung 5493f188c7 KNF: de-__P, bzero -> memset, bcmp -> memcmp. Remove extraneous
parentheses in return statements.

Cosmetic: don't open-code TAILQ_FOREACH().

Cosmetic: change types of variables to avoid oodles of casts: in
   in6_src.c, avoid casts by changing several route_in6 pointers
   to struct route pointers.  Remove unnecessary casts to caddr_t
   elsewhere.

Pave the way for eliminating address family-specific route caches:
   soon, struct route will not embed a sockaddr, but it will hold
   a reference to an external sockaddr, instead.  We will set the
   destination sockaddr using rtcache_setdst().  (I created a stub
   for it, but it isn't used anywhere, yet.)  rtcache_free() will
   free the sockaddr.  I have extracted from rtcache_free() a helper
   subroutine, rtcache_clear().  rtcache_clear() will "forget" a
   cached route, but it will not forget the destination by releasing
   the sockaddr.  I use rtcache_clear() instead of rtcache_free()
   in rtcache_update(), because rtcache_update() is not supposed
   to forget the destination.

Constify:

   1 Introduce const accessor for route->ro_dst, rtcache_getdst().

   2 Constify the 'dst' argument to ifnet->if_output().  This
     led me to constify a lot of code called by output routines.

   3 Constify the sockaddr argument to protosw->pr_ctlinput.  This
     led me to constify a lot of code called by ctlinput routines.

   4 Introduce const macros for converting from a generic sockaddr
     to family-specific sockaddrs, e.g., sockaddr_in: satocsin6,
     satocsin, et cetera.
2007-02-17 22:34:07 +00:00
dyoung 05b0abac15 Don't open-code LIST_FOREACH(). 2007-02-17 06:11:25 +00:00
joerg eb04733c4e Introduce new helper functions to abstract the route caching.
rtcache_init and rtcache_init_noclone lookup ro_dst and store
the result in ro_rt, taking care of the reference counting and
calling the domain specific route cache.
rtcache_free checks if a route was cashed and frees the reference.
rtcache_copy copies ro_dst of the given struct route, checking that
enough space is available and incrementing the reference count of the
cached rtentry if necessary.
rtcache_check validates that the cached route is still up. If it isn't,
it tries to look it up again. Afterwards ro_rt is either a valid again
or NULL.
rtcache_copy is used internally.

Adjust to callers of rtalloc/rtflush in the tree to check the sanity of
ro_dst first (if necessary). If it doesn't fit the expectations, free
the cache, otherwise check if the cached route is still valid. After
that combination, a single check for ro_rt == NULL is enough to decide
whether a new lookup needs to be done with a different ro_dst.
Make the route checking in gre stricter by repeating the loop check
after revalidation.
Remove some unused RADIX_MPATH code in in6_src.c. The logic is slightly
changed here to first validate the route and check RTF_GATEWAY
afterwards. This is sementically equivalent though.
etherip doesn't need sc_route_expire similiar to the gif changes from
dyoung@ earlier.

Based on the earlier patch from dyoung@, reviewed and discussed with
him.
2006-12-15 21:18:52 +00:00