Previously, sorele() always required the socket lock and dropped the
lock if the released reference was not the last reference. Many
callers locked the socket lock just before calling sorele() resulting
in a wasted lock/unlock when not dropping the last reference.
Move the previous implementation of sorele() into a new
sorele_locked() function and use it instead of sorele() for various
places in uipc_socket.c that called sorele() while already holding the
socket lock.
The sorele() macro now uses refcount_release_if_not_last() try to drop
the socket reference without locking the socket. If that shortcut
fails, it locks the socket and calls sorele_locked().
Reviewed by: kib, markj
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D32741
Create the initial pool of kprocs on demand when the first socket AIO
request is submitted instead. The pool of kprocs used for other AIO
requests is similarly created on first use.
Reviewed by: asomers
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D32468
Some system software expects to be able to read at least the number of
bytes returned by FIONREAD. When control messages are counted in this
return value, this assumption is violated. Follow Linux and OpenBSD
here (as well as our own kevent(EVFILT_READ)) and only return the number
of data bytes available.
Reported by: avg
MFC after: 2 weeks
soo_aio_queue() did not handle the possibility that the provided socket
is a listening socket. Up until recently, to fix this one would have to
acquire the socket lock first and check, since the socket buffer locks
were destroyed by listen(2).
Now that the socket buffer locks belong to the socket, simply check
SOLISTENING(so) after acquiring them, and make listen(2) return an error
if any AIO jobs are enqueued on the socket.
Add a couple of simple regression test cases.
Note that this fixes things only for the default AIO implementation;
cxgbe(4)'s TCP offload has a separate pru_aio_queue implementation which
requires its own solution.
Reported by: syzbot+c8aa122fa2c6a4e2a28b@syzkaller.appspotmail.com
Reported by: syzbot+39af117d43d4f0faf512@syzkaller.appspotmail.com
Reported by: syzbot+60cceb9569145a0b993b@syzkaller.appspotmail.com
Reported by: syzbot+2d522c5db87710277ca5@syzkaller.appspotmail.com
Reviewed by: tuexen, gallatin, jhb
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D31901
This reverts a portion of 274579831b ("capsicum: Limit socket
operations in capability mode") as at least rtsol and dhcpcd rely on
being able to configure network interfaces while in capability mode.
Reported by: bapt, Greg V
Sponsored by: The FreeBSD Foundation
Capsicum did not prevent certain privileged networking operations,
specifically creation of raw sockets and network configuration ioctls.
However, these facilities can be used to circumvent some of the
restrictions that capability mode is supposed to enforce.
Add capability mode checks to disallow network configuration ioctls and
creation of sockets other than PF_LOCAL and SOCK_DGRAM/STREAM/SEQPACKET
internet sockets.
Reviewed by: oshogbo
Discussed with: emaste
Reported by: manu
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D29423
This allows slightly more efficient opcode testing in-kernel. It is
transparent to userland, except to applications that sneakily submit
aio fsync or aio mlock operations via lio_listio, which has never been
documented, requires the use of deliberately undefined constants
(LIO_SYNC and LIO_MLOCK), and is arguably a bug.
Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D27942
POSIX AIO is great, but it lacks vectored I/O functions. This commit
fixes that shortcoming by adding aio_writev and aio_readv. They aren't
part of the standard, but they're an obvious extension. They work just
like their synchronous equivalents pwritev and preadv.
It isn't yet possible to use vectored aiocbs with lio_listio, but that
could be added in the future.
Reviewed by: jhb, kib, bcr
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D27743
access the socket send or receive buffer. This is not possible for
listening sockets since r319722.
Because send()/recv() calls fail on listening sockets, fail also ioctl()
indicating EINVAL.
PR: 250366
Reported by: Yong-Hao Zou
Reviewed by: glebius, rscheff
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D26897
Otherwise nothing synchronizes with a concurrent conversion of the
socket to a listening socket.
Only the PF_LOCAL protocols implement pru_sense, and it is safe to hold
the socket lock there, so do so for now.
Reported by: syzbot+4801f1b79ea40953ca8e@syzkaller.appspotmail.com
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT
Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718
pru_peeraddr().
This is already true when called via kern_getsockname() and
kern_getpeername(). This patch sets it also, when they arecalled
via soo_fill_kinfo(). This is necessary, since the corresponding
functions for SCTP require the vnet to be set. Without this,
if a process having an wildcard bound SCTP socket is
terminated and a core is written, the kernel panics.
Reviewed by: bz
Differential Revision: https://reviews.freebsd.org/D13652
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
The AIO job holds a reference on the associated file descriptor, so the
socket's count should already be > 0. This fixes a LOR with the socket
buffer lock after recent socket locking changes in HEAD.
Sponsored by: Chelsio Communications
o Separate fields of struct socket that belong to listening from
fields that belong to normal dataflow, and unionize them. This
shrinks the structure a bit.
- Take out selinfo's from the socket buffers into the socket. The
first reason is to support braindamaged scenario when a socket is
added to kevent(2) and then listen(2) is cast on it. The second
reason is that there is future plan to make socket buffers pluggable,
so that for a dataflow socket a socket buffer can be changed, and
in this case we also want to keep same selinfos through the lifetime
of a socket.
- Remove struct struct so_accf. Since now listening stuff no longer
affects struct socket size, just move its fields into listening part
of the union.
- Provide sol_upcall field and enforce that so_upcall_set() may be called
only on a dataflow socket, which has buffers, and for listening sockets
provide solisten_upcall_set().
o Remove ACCEPT_LOCK() global.
- Add a mutex to socket, to be used instead of socket buffer lock to lock
fields of struct socket that don't belong to a socket buffer.
- Allow to acquire two socket locks, but the first one must belong to a
listening socket.
- Make soref()/sorele() to use atomic(9). This allows in some situations
to do soref() without owning socket lock. There is place for improvement
here, it is possible to make sorele() also to lock optionally.
- Most protocols aren't touched by this change, except UNIX local sockets.
See below for more information.
o Reduce copy-and-paste in kernel modules that accept connections from
listening sockets: provide function solisten_dequeue(), and use it in
the following modules: ctl(4), iscsi(4), ng_btsocket(4), ng_ksocket(4),
infiniband, rpc.
o UNIX local sockets.
- Removal of ACCEPT_LOCK() global uncovered several races in the UNIX
local sockets. Most races exist around spawning a new socket, when we
are connecting to a local listening socket. To cover them, we need to
hold locks on both PCBs when spawning a third one. This means holding
them across sonewconn(). This creates a LOR between pcb locks and
unp_list_lock.
- To fix the new LOR, abandon the global unp_list_lock in favor of global
unp_link_lock. Indeed, separating these two locks didn't provide us any
extra parralelism in the UNIX sockets.
- Now call into uipc_attach() may happen with unp_link_lock hold if, we
are accepting, or without unp_link_lock in case if we are just creating
a socket.
- Another problem in UNIX sockets is that uipc_close() basicly did nothing
for a listening socket. The vnode remained opened for connections. This
is fixed by removing vnode in uipc_close(). Maybe the right way would be
to do it for all sockets (not only listening), simply move the vnode
teardown from uipc_detach() to uipc_close()?
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D9770
Extend the ino_t, dev_t, nlink_t types to 64-bit ints. Modify
struct dirent layout to add d_off, increase the size of d_fileno
to 64-bits, increase the size of d_namlen to 16-bits, and change
the required alignment. Increase struct statfs f_mntfromname[] and
f_mntonname[] array length MNAMELEN to 1024.
ABI breakage is mitigated by providing compatibility using versioned
symbols, ingenious use of the existing padding in structures, and
by employing other tricks. Unfortunately, not everything can be
fixed, especially outside the base system. For instance, third-party
APIs which pass struct stat around are broken in backward and
forward incompatible ways.
Kinfo sysctl MIBs ABI is changed in backward-compatible way, but
there is no general mechanism to handle other sysctl MIBS which
return structures where the layout has changed. It was considered
that the breakage is either in the management interfaces, where we
usually allow ABI slip, or is not important.
Struct xvnode changed layout, no compat shims are provided.
For struct xtty, dev_t tty device member was reduced to uint32_t.
It was decided that keeping ABI compat in this case is more useful
than reporting 64-bit dev_t, for the sake of pstat.
Update note: strictly follow the instructions in UPDATING. Build
and install the new kernel with COMPAT_FREEBSD11 option enabled,
then reboot, and only then install new world.
Credits: The 64-bit inode project, also known as ino64, started life
many years ago as a project by Gleb Kurtsou (gleb). Kirk McKusick
(mckusick) then picked up and updated the patch, and acted as a
flag-waver. Feedback, suggestions, and discussions were carried
by Ed Maste (emaste), John Baldwin (jhb), Jilles Tjoelker (jilles),
and Rick Macklem (rmacklem). Kris Moore (kris) performed an initial
ports investigation followed by an exp-run by Antoine Brodin (antoine).
Essential and all-embracing testing was done by Peter Holm (pho).
The heavy lifting of coordinating all these efforts and bringing the
project to completion were done by Konstantin Belousov (kib).
Sponsored by: The FreeBSD Foundation (emaste, kib)
Differential revision: https://reviews.freebsd.org/D10439
Add a MSG_MOREOTOCOME message flag. When this flag is set, sosend*
set PRUS_MOREOTOCOME when invoking the protocol send method. The aio
worker tasks for sending on a socket set this flag when there are
additional write jobs waiting on the socket buffer.
Reviewed by: adrian
MFC after: 1 month
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D8955
File and disk-backed I/O requests store counts of read/written disk
blocks in each AIO job so that they can be charged to the thread that
completes an AIO request via aio_return() or aio_waitcomplete(). This
change extends AIO jobs to store counts of received/sent messages and
updates socket backends to set these counts accordingly. Note that
the socket backends are careful to only charge a single messages for
each AIO request even though a single request on a blocking socket might
invoke sosend or soreceive multiple times. This is to mimic the
resource accounting of synchronous read/write.
Adjust the UNIX socketpair AIO test to verify that the message resource
usage counts update accordingly for aio_read and aio_write.
Approved by: re (hrs)
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D6911
This reduces the size of kaiocb slightly. I've also added some generic
fields that other backends can use in place of the BIO-specific fields.
Change the socket and Chelsio DDP backends to use 'backend3' instead of
abusing _aiocb_private.status directly. This confines the use of
_aiocb_private to the AIO internals in vfs_aio.c.
Reviewed by: kib (earlier version)
Approved by: re (gjb)
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D6547
After the previous changes to fix requests on blocking sockets to complete
across multiple operations, an edge case exists where a request can be
cancelled after it has partially completed. POSIX doesn't appear to
dictate exactly how to handle this case, but in general I feel that
aio_cancel() should arrange to cancel any request it can, but that any
partially completed requests should return a partial completion rather
than ECANCELED. To that end, fix the socket AIO cancellation routine to
return a short read/write if a partially completed request is cancelled
rather than ECANCELED.
Sponsored by: Chelsio Communications
Always requeue an AIO job at the head of the socket buffer's queue if
sosend() or soreceive() returns EWOULDBLOCK on a blocking socket.
Previously, requests were only requeued if they returned EWOULDBLOCK
and completed no data. Now after a partial completion on a blocking
socket the request is queued and the remaining request is retried when
the socket is ready. This allows writes larger than the currently
available space on a blocking socket to fully complete. Reads on a
blocking socket that satifsy the low watermark can still return a short
read (same as read()).
In order to track previously completed data, the internal 'status'
field of the AIO job is used to store the amount of previously
computed data.
Non-blocking sockets continue to return short completions for both
reads and writes.
Add a test for a "large" AIO write on a blocking socket that writes
twice the socket buffer size to a UNIX domain socket.
Sponsored by: Chelsio Communications
improve cancellation robustness.
Introduce a new file operation, fo_aio_queue, which is responsible for
queueing and completing an asynchronous I/O request for a given file.
The AIO subystem now exports library of routines to manipulate AIO
requests as well as the ability to run a handler function in the
"default" pool of AIO daemons to service a request.
A default implementation for file types which do not include an
fo_aio_queue method queues requests to the "default" pool invoking the
fo_read or fo_write methods as before.
The AIO subsystem permits file types to install a private "cancel"
routine when a request is queued to permit safe dequeueing and cleanup
of cancelled requests.
Sockets now use their own pool of AIO daemons and service per-socket
requests in FIFO order. Socket requests will not block indefinitely
permitting timely cancellation of all requests.
Due to the now-tight coupling of the AIO subsystem with file types,
the AIO subsystem is now a standard part of all kernels. The VFS_AIO
kernel option and aio.ko module are gone.
Many file types may block indefinitely in their fo_read or fo_write
callbacks resulting in a hung AIO daemon. This can result in hung
user processes (when processes attempt to cancel all outstanding
requests during exit) or a hung system. To protect against this, AIO
requests are only permitted for known "safe" files by default. AIO
requests for all file types can be enabled by setting the new
vfs.aio.enable_usafe sysctl to a non-zero value. The AIO tests have
been updated to skip operations on unsafe file types if the sysctl is
zero.
Currently, AIO requests on sockets and raw disks are considered safe
and are enabled by default. aio_mlock() is also enabled by default.
Reviewed by: cem, jilles
Discussed with: kib (earlier version)
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D5289
sb_cc member of struct sockbuf to a couple of inline functions:
sbavail() and sbused()
Right now they are equal, but once notion of "not ready socket buffer data",
will be checked in, they are going to be different.
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
struct kinfo_file.
- Move the various fill_*_info() methods out of kern_descrip.c and into the
various file type implementations.
- Rework the support for kinfo_ofile to generate a suitable kinfo_file object
for each file and then convert that to a kinfo_ofile structure rather than
keeping a second, different set of code that directly manipulates
type-specific file information.
- Remove the shm_path() and ksem_info() layering violations.
Differential Revision: https://reviews.freebsd.org/D775
Reviewed by: kib, glebius (earlier version)
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
to implement fchown(2) and fchmod(2) support for several file types
that previously lacked it. Add MAC entries for chown/chmod done on
posix shared memory and (old) in-kernel posix semaphores.
Based on the submission by: glebius
Reviewed by: rwatson
Approved by: re (bz)
VNET socket push back:
try to minimize the number of places where we have to switch vnets
and narrow down the time we stay switched. Add assertions to the
socket code to catch possibly unset vnets as seen in r204147.
While this reduces the number of vnet recursion in some places like
NFS, POSIX local sockets and some netgraph, .. recursions are
impossible to fix.
The current expectations are documented at the beginning of
uipc_socket.c along with the other information there.
Sponsored by: The FreeBSD Foundation
Sponsored by: CK Software GmbH
Reviewed by: jhb
Tested by: zec
Tested by: Mikolaj Golub (to.my.trociny gmail.com)
MFC after: 2 weeks
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)
easily determine how much space is left in the send queue; they do not
need to know the send queue size.
NetBSD revisions:
sys_socket.c r1.41, 1.42
filio.h r1.9
Obtained from: NetBSD
Approved by: re (kensmith)
inbound data waiting on a filedescriptor, such as a pipe or a socket,
for instance by using select(2), poll(2), kqueue(2), ioctl(FIONREAD)
etc.
But we have no way of finding out if written data have yet to be
disposed of, for instance, transmitted (and ack'ed!) to some remote
host, or read by the applicantion at the far end of the pipe.
The closest we get, is calling shutdown(2) on a TCP socket in
non-blocking mode, but this has the undesirable sideeffect of
preventing future communication.
Add a complement to FIONREAD, called FIONWRITE, which returns the
number of bytes not yet properly disposed of. Implement it for
all sockets.
Background:
A HTTP server will want to time out connections, if no new request
arrives within a certain period after the last transmitted response
has actually been sent (and ack'ed).
For a busy HTTP server, this timeout can be subsecond duration.
In order to signal to a load-balancer that the connection is truly
dead, TCP_RST will be the preferred method, as this avoids the need
for a RTT delay for FIN handshaking, with a client which, surprisingly
often, no longer at the remote IP number.
If a slow, distant client is being served a response which is big
enough to fill the window, but small enough to fit in the socket
buffer, the write(2) call will return immediately.
If the session timeout is armed at that time, all bytes in the
response may not have been transmitted by the time it fires.
FIONWRITE allows the timeout to check that no data is outstanding
on the connection, before it TCP_RST's it.
Input & Idea from: rwatson
Approved by: re (kib)
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.
Discussed with: pjd
count of the number of registered policies.
Rather than unconditionally locking sockets before passing them into MAC,
lock them in the MAC entry points only if mac_policy_count is non-zero.
This avoids locking overhead for a number of socket system calls when no
policies are registered, eliminating measurable overhead for the MAC
Framework for the socket subsystem when there are no active policies.
Possibly socket locks should be acquired by policies if they are required
for socket labels, which would further avoid locking overhead when there
are policies but they don't require labeling of sockets, or possibly
don't even implement socket controls.
Obtained from: TrustedBSD Project
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)
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
This makes it possible to support ftruncate() on non-vnode file types in
the future.
- 'struct fileops' grows a 'fo_truncate' method to handle an ftruncate() on
a given file descriptor.
- ftruncate() moves to kern/sys_generic.c and now just fetches a file
object and invokes fo_truncate().
- The vnode-specific portions of ftruncate() move to vn_truncate() in
vfs_vnops.c which implements fo_truncate() for vnode file types.
- Non-vnode file types return EINVAL in their fo_truncate() method.
Submitted by: rwatson
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:
mac_<object>_<method/action>
mac_<object>_check_<method/action>
The previous naming scheme was inconsistent and mostly
reversed from the new scheme. Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier. Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods. Also simplify, slightly,
some entry point names.
All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.
Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer
