the use of divert sockets to dead locks. A number of LORs have been reported
between divert and a number of other network subsystems including: IPSEC, Pfil,
multicast, ipfw and others. Other dead locks could occur because of recursive
entry into the IP stack. This change should take care of most if not all of
these issues.
A summary of the changes follow:
- We disallow multicast operations on divert sockets. It really doesn't make
semantic sense to allow this, since typically you would set multicast
parameters on multicast end points.
NOTE: As a part of this change, we actually dis-allow multicast options on
any socket that IS a divert socket OR IS NOT a SOCK_RAW or SOCK_DGRAM family
- We check to see if there are any socket options that have been specified on
the socket, and if there was (which is very un-common and also probably
doesnt make sense to support) we duplicate the mbuf carrying the options.
- We then drop the INP/INFO locks over the call to ip_output(). It should be
noted that since we no longer support multicast operations on divert sockets
and we have duplicated any socket options, we no longer need the reference
to the pcb to be coherent.
- Finally, we replaced the call to ip_input() to use netisr queuing. This
should remove the recursive entry into the IP stack from divert.
By dropping the locks over the call to ip_output() we eliminate all the lock
ordering issues above. By switching over to netisr on the inbound path,
we can no longer recursively enter the ip_input() code via divert.
I have tested this change by using the following command:
ipfwpcap -r 8000 - | tcpdump -r - -nn -v
This should exercise the input and re-injection (outbound) path, which is
very similar to the work load performed by natd(8). Additionally, I have
run some ospf daemons which have a heavy reliance on raw sockets and
multicast.
Approved by: re@ (kensmith)
MFC after: 1 month
LOR: 163
LOR: 181
LOR: 202
LOR: 203
Discussed with: julian, andre et al (on freebsd-net)
In collaboration with: bms [1], rwatson [2]
[1] bms helped out with the multicast decisions
[2] rwatson submitted the original netisr patches and came up with some
of the original ideas on how to combat this issue.
for bakeoff.. using the next sequential ones)
- In cookie processing 1-2-1, we did not increment the stcb
refcnt before releasing the tcb lock. We need to do this
to keep the tcb from being freed by a abort or ?? unlikely
but worth doing. Also get rid of unneed INP_WLOCK.
- extra receive info included the rcvinfo which killed the
padding/alignment. We now redefine all the fields properly
so they both align properly both to 128 bytes.
- A peeled off socket would not close without an error due to
its misguided idea that sctp_disconnect() was not supported
on it. This fixes it so it goes through the proper path.
- When an assoc was being deleted after abort (via a timer) a
small race condition exists where we might take a packet for
the old assoc (since we are waiting for a cleanup timer). This
state especially happens in mac. We now add a state in the asoc
so these can properly handle the packet as OOTB.
Approved by: re@freebsd.org(Ken Smith)
previously conditionally acquired Giant based on debug.mpsafenet. As that
has now been removed, they are no longer required. Removing them
significantly simplifies error-handling in the socket layer, eliminated
quite a bit of unwinding of locking in error cases.
While here clean up the now unneeded opt_net.h, which previously was used
for the NET_WITH_GIANT kernel option. Clean up some related gotos for
consistency.
Reviewed by: bz, csjp
Tested by: kris
Approved by: re (kensmith)
Also rename the related functions in a similar way.
There are no functional changes.
For a packet coming in with IPsec tunnel mode, the default is
to only call into the firewall with the "outer" IP header and
payload.
With this option turned on, in addition to the "outer" parts,
the "inner" IP header and payload are passed to the
firewall too when going through ip_input() the second time.
The option was never only related to a gif(4) tunnel within
an IPsec tunnel and thus the name was very misleading.
Discussed at: BSDCan 2007
Best new name suggested by: rwatson
Reviewed by: rwatson
Approved by: re (bmah)
be in ticks "for algorithm stability" when originally committed, it turns
out that it has a significant impact in timing out connections. When we
changed HZ from 100 to 1000, this had a big effect on reducing the time
before dropping connections.
To demonstrate, boot with kern.hz=100. ssh to a box on local ethernet
and establish a reliable round-trip-time (ie: type a few commands).
Then unplug the ethernet and press a key. Time how long it takes to
drop the connection.
The old behavior (with hz=100) caused the connection to typically drop
between 90 and 110 seconds of getting no response.
Now boot with kern.hz=1000 (default). The same test causes the ssh session
to drop after just 9-10 seconds. This is a big deal on a wifi connection.
With kern.hz=1000, change sysctl net.inet.tcp.rexmit_min from 3 to 30.
Note how it behaves the same as when HZ was 100. Also, note that when
booting with hz=100, net.inet.tcp.rexmit_min *used* to be 30.
This commit changes TCPTV_MIN to be scaled with hz. rexmit_min should
always be about 30. If you set hz to Really Slow(TM), there is a safety
feature to prevent a value of 0 being used.
This may be revised in the future, but for the time being, it restores the
old, pre-hz=1000 behavior, which is significantly less annoying.
As a workaround, to avoid rebooting or rebuilding a kernel, you can run
"sysctl net.inet.tcp.rexmit_min=30" and add "net.inet.tcp.rexmit_min=30"
to /etc/sysctl.conf. This is safe to run from 6.0 onwards.
Approved by: re (rwatson)
Reviewed by: andre, silby
<netinet/tcp_fsm.h> is included into any compilation unit that needs
tcpstates[]. Also remove incorrect extern declarations and TCPDEBUG
conditionals. This allows kernels both with and without TCPDEBUG to
build, and unbreaks the tinderbox.
Approved by: re (rwatson)
sys.net.inet.tcp.log_debug = 1
It defaults to enabled for the moment and is to be turned off for
the next release like other diagnostics from development branches.
It is important to note that sysctl sys.net.inet.tcp.log_in_vain
uses the same logging function as log_debug. Enabling of the former
also causes the latter to engage, but not vice versa.
Use consistent terminology in tcp log messages:
"ignored" means a segment contains invalid flags/information and
is dropped without changing state or issuing a reply.
"rejected" means a segments contains invalid flags/information but
is causing a reply (usually RST) and may cause a state change.
Approved by: re (rwatson)
SYNCACHE_TIMEOUT to new function syncache_timeout().
o Fix inverted timeout callout engagement logic to actually
enable the timer for the bucket row. Before SYN|ACK was
not retransmitted.
o Simplify SYN|ACK retransmit timeout backoff calculation.
o Improve logging of retransmit and timeout events.
o Reset timeout when duplicate SYN arrives.
o Add comments.
o Rearrange SYN cookie statistics counting.
Bug found by: silby
Submitted by: silby (different version)
Approved by: re (rwatson)
syncache_rst().
o Fix tests for flag combinations of RST and SYN, ACK, FIN. Before
a RST for a connection in syncache did not properly free the entry.
o Add more detailed logging.
Approved by: re (rwatson)
- Fix addrs's error checking of sctp_sendx(3) when addrcnt is less than
SCTP_SMALL_IOVEC_SIZE
- re-add back inpcb_bind local address check bypass capability
- Fix it so sctp_opt_info is independant of assoc_id postion.
- Fix cookie life set to use MSEC_TO_TICKS() macro.
- asconf changes
o More comment changes/clarifications related to the old local address
"not" list which is now an explicit restricted list.
o Rename some functions for clarity:
- sctp_add/del_local_addr_assoc to xxx_local_addr_restricted()
- asconf related iterator functions to sctp_asconf_iterator_xxx()
o Fix bug when the same address is deleted and added (and removed from
the asconf queue) where the ifa is "freed" twice refcount wise,
possibly freeing it completely.
o Fix bug in output where the first ASCONF would not go out after the
last address is changed (e.g. only goes out when retransmitted).
o Fix bug where multiple ASCONFs can be bundled in the same packet with
the and with the same serial numbers.
o Fix asconf stcb iterator to not send ASCONF until after all work
queue entries have been processed.
o Change behavior so that when the last address is deleted (auto asconf
on a bound all endpoint) no action is taken until an address is
added; at that time, an ASCONF add+delete is sent (if the assoc
is still up).
o Fix local address counting so that address scoping is taken into
account.
o #ifdef SCTP_TIMER_BASED_ASCONF the old timer triggered sending
of ASCONF (after an RTO). The default now is to send
ASCONF immediately (except for the case of changing/deleting the
last usable address).
Approved by: re(ken smith)@freebsd.org
- remove duplicate #include <sys/priv.h> that is not under
#ifdef FreeBSD version to allow compile on 6.1
- static analysis changes per the cisco SA tool including:
o some SA_IGNORE comments
o some checks for NULL before unlock.
o type corrections int -> size_t
- Fix it so sctp_alloc_asoc takes a thread/proc argument. Without this
we pass a NULL in to bind on implicit assoc setup and crash :-(
Approved by: re@freebsd.org(Ken Smith)
UDPv4 features to UDPv6:
- Add MAC checks on delivery and MAC labeling on transmit.
- Check for (and reject) datagrams with destination port 0.
- For multicast delivery, check the source port only if the socket being
considered as a destination has been connected.
- Implement UDP blackholing based on net.inet.udp.blackhole.
- Add a new ICMPv6 unreachable reply rate limiting category for failed
delivery attempts and implement rate limiting for UDPv6 (submitted by
bz).
Approved by: re (kensmith)
Reviewed by: bz
- use proper tick gathering macro instead of ticks directly.
- Placed reasonable boundaries on sets that a user can do
that are converted to ticks from ms.
- Fix CMT_PF to always check to be sure CMT is on.
- Fix ticks use of CMT_PF.
- put back code to allow asconfs to be queued while INITs are in flight
and before the assoc is established.
- During window probes, an ack'd packet might be left with the window
probe mark on it causing it to be retransmitted. Change so that
the flight decrease macro clears the window_probe mark.
- Additional logging flight size/reading and ASOC LOG. This
is only enabled if you manually insert things into opt_sctp.h
since its a set of debug code only.
- Found an interesting SMP race in the way data was appended which
could cause a reader to lose a part of a message, had to
reorder when we marked the message was complete to after
the data was appended.
- bug in ADD-IP for the subset bound socket case when the peer has only
one address
- fix ASCONF implicit success/error handling case
- proper support of jails in Freebsd 6>
- copy out the timeval for the 64 bit sparc world on cookie-echo
alignment error crashes without this).
Approved by: re(Ken Smith)
- CMT_PF states added (w/sysctl to turn the PF version on)
- sctp_input.c had a missing incr of cookie case when the
auth was bad. This meant a free was called without an
increment to refcnt, added increment like rest of code.
- There was a case, unlikely, when the scope of the destination
changed (this is a TSNH case). In that case, it would not free
the alloc'ed asoc (in sctp_input.c).
- When listed addresses found a colliding cookie/Init, then
the collided upon tcb was not unlocked in sctp_pcb.c
- Add error checking on arguments of sctp_sendx(3) to prevent it from
referencing a NULL pointer.
- Fix an error return of sctp_sendx(3), it was returing
ENOMEM not -1.
- Get assoc id was changed to use the sanctified socket api
method for getting a assoc id (PEER_ADDR_INFO instead of
PEER_ADDR_PARAMS).
- Fix it so a peeled off socket will get a proper error return
if it trys to send to a different address then it is connected to.
- Fix so that select_a_stream can avoid an endless loop that
could hang a caller.
- time_entered (state set time) was not being set in all cases
to the time we went established.
Approved by: re(ken smith)
- Move udp_sendspace and udp_recvspace global variables and associated
sysctls to the top of the file where most other such things are present.
- Rename static variable 'blackhole' to 'udp_blackhole' and unstaticize
so that we can add blackhole support for UDPv6 using the same MIB
variable.
- Move udp_append() above udp_input() to match the function order in
udp6_usrreq.c.
Approved by: re (kensmith)
With the in_mcast.c code, if an interface for an IPv4 multicast join was
not specified, and a route did not exist for the specified group in the
unicast forwarding tables, the join would be rejected with the error
EADDRNOTAVAIL.
This change restores the old behaviour whereby if no interface is specified,
and no route exists for the group destination, the IPv4 address list is
walked to find a non-loopback, multicast-capable interface to satisfy
the join request.
This should resolve problems with starting multicast services during
system boot or when a default forwarding entry does not exist.
Approved by: re (rwatson)
free to be consistent with other error handling, and release socket buffer
lock before freeing mbufs and statistics updates rather than after.
Approved by: re (kensmith)
call the sctp_free_remote_address() function.
- Assure that when we allocate a chunk the whoTo is NULL,
also when we free it and place it into the cache we NULL
it (that way the consolidation code will always work).
- Fix a small race, when a empty data holder is left on the stream
out queue, and both sides do a shutdown, the empty data holder
would prevent us from sending a SHUTDOWN-ACK and at the same time we
never would cleanup the empty holder (since nothing was ever in queue).
We now add a utility function that a) cleans up empty holders and
b) properly determines if there are still pending data chunks on
the stream out wheel.
Approved by: re@freebsd.org (Ken Smith)
This commit includes only the kernel files, the rest of the files
will follow in a second commit.
Reviewed by: bz
Approved by: re
Supported by: Secure Computing
- Fix fwd-tsn to use proper accessor so it does not overrun mbufs
- Fix stream reset error reporting to actually work (it has always been
broken if the peer rejects a stream reset)
- Some 64 bit friendly changes
Approved by: re(bmah@freebsd.org)
- to show a specific set: ipfw set 3 show
- to delete rules from the set: ipfw set 9 delete 100 200 300
- to flush the set: ipfw set 4 flush
- to reset rules counters in the set: ipfw set 1 zero
PR: kern/113388
Submitted by: Andrey V. Elsukov
Approved by: re (kensmith)
MFC after: 6 weeks
to hold off freeing if there is data pending ... someone
might do send/close. Which means we want the data to
go and then close it after startup. Added comments to
the code as well to note that this is done for a reason.
- re-factor the packet drop in sctp_output a bit more, we don't need the
trim after all, but the size calc is now corrected.
- When a assoc is in the COOKIE-ECHO/COOKIE-WAIT state and the user
closes, it should not matter if data is queued, the assoc should be
purged.
- In error leg a missing free_chunk when iph comes in NULL (should not
happen but just in case).
to nonzero you fulfill the same function as the variable 'cmp'. so you
might as well zero match and test against it later.
Reviewed by: timeout on review request
