Singed calculations in cubic_cwnd() can result in negative cwnd
value which is then cast to an unsigned value. Values less than
1 mss are generally bad for other parts of the code, also fixed.
Submitted by: Jason Eggleston <jason@eggnet.com>
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14141
controlled by the TCP_BLACKBOX option.
Enable this as part of amd64 GENERIC. For now, leave it disabled on
other platforms.
Sponsored by: Netflix, Inc.
Forwarded packets passed through PFIL_OUT, which made it difficult for
firewalls to figure out if they were forwarding or producing packets. This in
turn is an issue for pf for IPv6 fragment handling: it needs to call
ip6_output() or ip6_forward() to handle the fragments. Figuring out which was
difficult (and until now, incorrect).
Having pfil distinguish the two removes an ugly piece of code from pf.
Introduce a new variant of the netpfil callbacks with a flags variable, which
has PFIL_FWD set for forwarded packets. This allows pf to reliably work out if
a packet is forwarded.
Reviewed by: ae, kevans
Differential Revision: https://reviews.freebsd.org/D13715
summits at BSDCan and BSDCam in 2017.
The TCP Blackbox Recorder allows you to capture events on a TCP connection
in a ring buffer. It stores metadata with the event. It optionally stores
the TCP header associated with an event (if the event is associated with a
packet) and also optionally stores information on the sockets.
It supports setting a log ID on a TCP connection and using this to correlate
multiple connections that share a common log ID.
You can log connections in different modes. If you are doing a coordinated
test with a particular connection, you may tell the system to put it in
mode 4 (continuous dump). Or, if you just want to monitor for errors, you
can put it in mode 1 (ring buffer) and dump all the ring buffers associated
with the connection ID when we receive an error signal for that connection
ID. You can set a default mode that will be applied to a particular ratio
of incoming connections. You can also manually set a mode using a socket
option.
This commit includes only basic probes. rrs@ has added quite an abundance
of probes in his TCP development work. He plans to commit those soon.
There are user-space programs which we plan to commit as ports. These read
the data from the log device and output pcapng files, and then let you
analyze the data (and metadata) in the pcapng files.
Reviewed by: gnn (previous version)
Obtained from: Netflix, Inc.
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D11085
from entering the TIME_WAIT state. However, it omits sending the ACK for the
FIN, which results in RST. This becomes a bigger deal if the sysctl
net.inet.tcp.blackhole is 2. In this case RST isn't send, so the other side of
the connection (also local) keeps retransmitting FINs.
To fix that in tcp_twstart() we will not call tcp_close() immediately. Instead
we will allocate a tcptw on stack and proceed to the end of the function all
the way to tcp_twrespond(), to generate the correct ACK, then we will drop the
last PCB reference.
While here, make a few tiny improvements:
- use bools for boolean variable
- staticize nolocaltimewait
- remove pointless acquisiton of socket lock
Reported by: jtl
Reviewed by: jtl
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D14697
through the lock-switching hoops.
A few of the INP lookup operations that lock INPs after the lookup do
so using this mechanism (to maintain lock ordering):
1. Lock lookup structure.
2. Find INP.
3. Acquire reference on INP.
4. Drop lock on lookup structure.
5. Acquire INP lock.
6. Drop reference on INP.
This change provides a slightly shorter path for cases where the INP
lock is uncontested:
1. Lock lookup structure.
2. Find INP.
3. Try to acquire the INP lock.
4. If successful, drop lock on lookup structure.
Of course, if the INP lock is contested, the functions will need to
revert to the previous way of switching locks safely.
This saves a few atomic operations when the INP lock is uncontested.
Discussed with: gallatin, rrs, rwatson
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D12911
ECN (ABE)" proposal to the New Reno congestion control algorithm module.
ABE reduces the amount of congestion window reduction in response to
ECN-signalled congestion relative to the loss-inferred congestion response.
More details about ABE can be found in the Internet-Draft:
https://tools.ietf.org/html/draft-ietf-tcpm-alternativebackoff-ecn
The implementation introduces four new sysctls:
- net.inet.tcp.cc.abe defaults to 0 (disabled) and can be set to non-zero to
enable ABE for ECN-enabled TCP connections.
- net.inet.tcp.cc.newreno.beta and net.inet.tcp.cc.newreno.beta_ecn set the
multiplicative window decrease factor, specified as a percentage, applied to
the congestion window in response to a loss-based or ECN-based congestion
signal respectively. They default to the values specified in the draft i.e.
beta=50 and beta_ecn=80.
- net.inet.tcp.cc.abe_frlossreduce defaults to 0 (disabled) and can be set to
non-zero to enable the use of standard beta (50% by default) when repairing
loss during an ECN-signalled congestion recovery episode. It enables a more
conservative congestion response and is provided for the purposes of
experimentation as a result of some discussion at IETF 100 in Singapore.
The values of beta and beta_ecn can also be set per-connection by way of the
TCP_CCALGOOPT TCP-level socket option and the new CC_NEWRENO_BETA or
CC_NEWRENO_BETA_ECN CC algo sub-options.
Submitted by: Tom Jones <tj@enoti.me>
Tested by: Tom Jones <tj@enoti.me>, Grenville Armitage <garmitage@swin.edu.au>
Relnotes: Yes
Differential Revision: https://reviews.freebsd.org/D11616
Current arp/nd code relies on the feedback from the datapath indicating
that the entry is still used. This mechanism is incorporated into the
arpresolve()/nd6_resolve() routines. After the inpcb route cache
introduction, the packet path for the locally-originated packets changed,
passing cached lle pointer to the ether_output() directly. This resulted
in the arp/ndp entry expire each time exactly after the configured max_age
interval. During the small window between the ARP/NDP request and reply
from the router, most of the packets got lost.
Fix this behaviour by plugging datapath notification code to the packet
path used by route cache. Unify the notification code by using single
inlined function with the per-AF callbacks.
Reported by: sthaug at nethelp.no
Reviewed by: ae
MFC after: 2 weeks
net.inet6.ip6.v6only=0.
Without this patch, the inp_vflag would have INP_IPV4 and the
INP_IPV6 flags for accepted TCP/IPv6 connections if the sysctl
variable net.inet6.ip6.v6only is 0. This resulted in netstat
to report the source and destination addresses as IPv4 addresses,
even they are IPv6 addresses.
PR: 226421
Reviewed by: bz, hiren, kib
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D13514
rrs - Lets make the LRO code look for true dup-acks and window update acks
fly on through and combine.
rrs - Make the LRO engine a bit more aware of ack-only seq space. Lets not
have it incorrectly wipe out newer acks for older acks when we have
out-of-order acks (common in wifi environments).
jeggleston - LRO eating window updates
Based on all of the above I think we are RFC compliant doing it this way:
https://tools.ietf.org/html/rfc1122
section 4.2.2.16
"Note that TCP has a heuristic to select the latest window update despite
possible datagram reordering; as a result, it may ignore a window update with
a smaller window than previously offered if neither the sequence number nor the
acknowledgment number is increased."
Submitted by: Kevin Bowling <kevin.bowling@kev009.com>
Reviewed by: rstone gallatin
Sponsored by: NetFlix and Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14540
for the minimum length.
This fixes a bug where cookies of length 2 bytes (which is smaller
than the minimum length of 4) is provided by the server.
Sponsored by: Netflix, Inc.
The conditional compilation support is now centralized in
tcp_fastopen.h and tcp_var.h. This doesn't provide the minimum
theoretical code/data footprint when TCP_RFC7413 is disabled, but
nearly all the TFO code should wind up being removed by the optimizer,
the additional footprint in the syncache entries is a single pointer,
and the additional overhead in the tcpcb is at the end of the
structure.
This enables the TCP_RFC7413 kernel option by default in amd64 and
arm64 GENERIC.
Reviewed by: hiren
MFC after: 1 month
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14048
[RFC7413]. It also includes a pre-shared key mode of operation in
which the server requires the client to be in possession of a shared
secret in order to successfully open TFO connections with that server.
The names of some existing fastopen sysctls have changed (e.g.,
net.inet.tcp.fastopen.enabled -> net.inet.tcp.fastopen.server_enable).
Reviewed by: tuexen
MFC after: 1 month
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14047
The keylist lock was not being acquired early enough. The only side
effect of this bug is that the effective add time of a new key could
be slightly later than it would have been otherwise, as seen by a TFO
client.
Reviewed by: tuexen
MFC after: 1 month
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14046
later by TCP-MD5 code.
This fixes the problem with broken TCP-MD5 over IPv4 when NIC has
disabled TCP checksum offloading.
PR: 223835
MFC after: 1 week
o added struct ipfw_dyn_info that keeps all needed for ipfw_chk and
for dynamic states implementation information;
o added DYN_LOOKUP_NEEDED() macro that can be used to determine the
need of new lookup of dynamic states;
o ipfw_dyn_rule now becomes obsolete. Currently it used to pass
information from kernel to userland only.
o IPv4 and IPv6 states now described by different structures
dyn_ipv4_state and dyn_ipv6_state;
o IPv6 scope zones support is added;
o ipfw(4) now depends from Concurrency Kit;
o states are linked with "entry" field using CK_SLIST. This allows
lockless lookup and protected by mutex modifications.
o the "expired" SLIST field is used for states expiring.
o struct dyn_data is used to keep generic information for both IPv4
and IPv6;
o struct dyn_parent is used to keep O_LIMIT_PARENT information;
o IPv4 and IPv6 states are stored in different hash tables;
o O_LIMIT_PARENT states now are kept separately from O_LIMIT and
O_KEEP_STATE states;
o per-cpu dyn_hp pointers are used to implement hazard pointers and they
prevent freeing states that are locklessly used by lookup threads;
o mutexes to protect modification of lists in hash tables now kept in
separate arrays. 65535 limit to maximum number of hash buckets now
removed.
o Separate lookup and install functions added for IPv4 and IPv6 states
and for parent states.
o By default now is used Jenkinks hash function.
Obtained from: Yandex LLC
MFC after: 42 days
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D12685
This used to work by accident with ld.bfd even though always_keepalive
was marked as static. LLD honors static more correctly, so export this
variable properly (including moving it into the tcp_* namespace).
Reviewed by: bz, emaste
MFC after: 2 weeks
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D14129
Mechanically replace uses of MALLOC/FREE with appropriate invocations of
malloc(9) / free(9) (a series of sed expressions). Something like:
* MALLOC(a, b, ... -> a = malloc(...
* FREE( -> free(
* free((caddr_t) -> free(
No functional change.
For now, punt on modifying contrib ipfilter code, leaving a definition of
the macro in its KMALLOC().
Reported by: jhb
Reviewed by: cy, imp, markj, rmacklem
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D14035
The header passed to these probes has some fields converted to host
order by tcp_fields_to_host(), so the tcpinfo_t translator doesn't do
what we want.
Submitted by: Hannes Mehnert
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D12647
the first mbuf of the reassembled datagram should have a pkthdr.
This was discovered with cxgbe(4) + IPSEC + ping with payload more than
interface MTU. cxgbe can generate !M_WRITEABLE mbufs and this results
in m_unshare being called on the reassembled datagram, and it complains:
panic: m_unshare: m0 0xfffff80020f82600, m 0xfffff8005d054100 has M_PKTHDR
PR: 224922
Reviewed by: ae@
MFC after: 1 week
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D14009
Add a new macro to clear both the L3 and L2 route caches, to
hopefully prevent future instances where only the L3 cache was
cleared when both should have been.
MFC after: 1 week
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D13989
Reviewed by: karels
When processing a SACK advancing the cumtsn-ack in fast recovery,
increment the miss-indications for all TSN's reported as missing.
Thanks to Fabian Ising for finding the bug and to Timo Voelker
for provinding a fix.
This fix moves also CMT related initialisation of some variables
to a more appropriate place.
MFC after: 1 week
Make the calloc wrappers behave as expected by using mallocarray.
It is rather weird that the malloc wrappers also zeroes the memory: update
a comment to reflect at least two cases where it is expected.
Reviewed by: tuexen
to ipfw in https://svnweb.freebsd.org/changeset/base/326233,
a dependency on the SCTP stack was added to ipfw by accident.
This was noted by Kevel Bowling in https://reviews.freebsd.org/D13594
where also a solution was suggested. This patch is based on Kevin's
suggestion, but implements the required SCTP checksum computation
without any dependency on other SCTP sources.
While there, do some cleanups and improve comments.
Thanks to Kevin Kevin Browling for reporting the issue and suggesting
a fix.
This reduces noise when kernel is compiled by newer GCC versions,
such as one used by external toolchain ports.
Reviewed by: kib, andrew(sys/arm and sys/arm64), emaste(partial), erj(partial)
Reviewed by: jhb (sys/dev/pci/* sys/kern/vfs_aio.c and sys/kern/kern_synch.c)
Differential Revision: https://reviews.freebsd.org/D10385
This option was used in the early days to allow performance measurements
extrapolating the use of SCTP checksum offloading. Since this feature
is now available, get rid of this option.
This also un-breaks the LINT kernel. Thanks to markj@ for making me
aware of the problem.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
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.
No functional change intended.
This is similar to the TCP case. where a TCP RST segment can be sent.
There is one limitation: When sending an ABORT in response to an incoming
packet, it should be tested if there is no ABORT chunk in the received
packet. Currently, it is only checked if the first chunk is an ABORT
chunk to avoid parsing the whole packet, which could result in a DOS attack.
Thanks to Timo Voelker for helping me to test this patch.
Reviewed by: bcr@ (man page part), ae@ (generic, non-SCTP part)
Differential Revision: https://reviews.freebsd.org/D13239
