to at least 64.
This is still just a coverup to avoid kernel panic and not an actual fix.
PR: 213232
Reviewed by: glebius
MFC after: 1 week
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D8272
Also renamed some tfo labels and added/reworked comments for clarity.
Based on an initial patch from jtl.
PR: 213424
Reviewed by: jtl
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D8235
compile when that option is configured. In tcp_destroy(), the error
variable is now only used in code enclosed in an '#ifdef TCP_HHOOK' block.
This broke the build for VNET images.
Enclose the error variable itself in an #ifdef block.
Submitted by: Shawn Webb <shawn.webb at hardenedbsd.org>
Reported by: Shawn Webb <shawn.webb at hardenedbsd.org>
PointyHat to: jtl
received on a TCP session that has entered the ESTABLISHED state. This
results in a lot of calls to reset the keepalive timer.
This patch changes the behavior so we set the keepalive timer for the
keepalive idle time (TP_KEEPIDLE). When the keepalive timer fires, it will
first check to see if the session has been idle for TP_KEEPIDLE ticks. If
not, it will reschedule the keepalive timer for the time the session will
have been idle for TP_KEEPIDLE ticks.
For a session with regular communication, the keepalive timer should fire
approximately once every TP_KEEPIDLE ticks. For sessions with irregular
communication, the keepalive timer might fire more often. But, the
disruption from a periodic keepalive timer should be less than the regular
cost of resetting the keepalive timer on every packet.
(FWIW, this change saved approximately 1.73% of the busy CPU cycles on a
particular test system with a heavy TCP output load. Of course, the
actual impact is very specific to the particular hardware and workload.)
Reviewed by: gallatin, rrs
MFC after: 2 weeks
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D8243
the TCP_RFC7413 kernel option. This change removes those few instructions
from the packet processing path.
While not strictly necessary, for the sake of consistency, I applied the
new IS_FASTOPEN macro to all places in the packet processing path that
used the (t_flags & TF_FASTOPEN) check.
Reviewed by: hiren
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D8219
TCPCB, it checks (so->so_options & SO_ACCEPTCONN) to determine whether or
not the socket is a listening socket. However, this causes the code to
access a different cacheline. If we first check if the socket is in the
LISTEN state, we can avoid accessing so->so_options when processing packets
received for ESTABLISHED sessions.
If INVARIANTS is defined, the code still needs to access both variables to
check that so->so_options is consistent with the state.
Reviewed by: gallatin
MFC after: 1 week
Sponsored by: Netflix
to add actions that run when a TCP frame is sent or received on a TCP
session in the ESTABLISHED state. In the base tree, this functionality is
only used for the h_ertt module, which is used by the cc_cdg, cc_chd, cc_hd,
and cc_vegas congestion control modules.
Presently, we incur overhead to check for hooks each time a TCP frame is
sent or received on an ESTABLISHED TCP session.
This change adds a new compile-time option (TCP_HHOOK) to determine whether
to include the hhook(9) framework for TCP. To retain backwards
compatibility, I added the TCP_HHOOK option to every configuration file that
already defined "options INET". (Therefore, this patch introduces no
functional change. In order to see a functional difference, you need to
compile a custom kernel without the TCP_HHOOK option.) This change will
allow users to easily exclude this functionality from their kernel, should
they wish to do so.
Note that any users who use a custom kernel configuration and use one of the
congestion control modules listed above will need to add the TCP_HHOOK
option to their kernel configuration.
Reviewed by: rrs, lstewart, hiren (previous version), sjg (makefiles only)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D8185
This change extends the nd6 lock to protect the ND prefix list as well
as the list of advertising routers associated with each prefix. To handle
cases where the nd6 lock must be dropped while iterating over either the
prefix or default router lists, a generation counter is used to track
modifications to the lists. Additionally, a new mutex is used to serialize
prefix on-link/off-link transitions. This mutex must be acquired before
the nd6 lock and is held while updating the routing table in
nd6_prefix_onlink() and nd6_prefix_offlink().
Reviewed by: ae, tuexen (SCTP bits)
Tested by: Jason Wolfe <jason@llnw.com>,
Larry Rosenman <ler@lerctr.org>
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D8125
In the persist case, take the SYN and FIN flags into account when updating
the sequence space sent.
Reviewed by: gnn
MFC after: 2 weeks
Sponsored by: Juniper Networks, Netflix
Differential Revision: https://reviews.freebsd.org/D7075
Tested by: Limelight, Netflix
A single gratuitous ARP (GARP) is always transmitted when an IPv4
address is added to an interface, and that is usually sufficient.
However, in some circumstances, such as when a shared address is
passed between cluster nodes, this single GARP may occasionally be
dropped or lost. This can lead to neighbors on the network link
working with a stale ARP cache and sending packets destined for
that address to the node that previously owned the address, which
may not respond.
To avoid this situation, GARP retransmissions can be enabled by setting
the net.link.ether.inet.garp_rexmit_count sysctl to a value greater
than zero. The setting represents the maximum number of retransmissions.
The interval between retransmissions is calculated using an exponential
backoff algorithm, doubling each time, so the retransmission intervals
are: {1, 2, 4, 8, 16, ...} (seconds).
Due to the exponential backoff algorithm used for the interval
between GARP retransmissions, the maximum number of retransmissions
is limited to 16 for sanity. This limit corresponds to a maximum
interval between retransmissions of 2^16 seconds ~= 18 hours.
Increasing this limit is possible, but sending out GARPs spaced
days apart would be of little use.
Submitted by: David A. Bright <david.a.bright@dell.com>
MFC after: 1 month
Relnotes: yes
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D7695
is NULL and the function jumps to the "release:" label.
For this case, the "inp" was write locked, but the code attempted to
read unlock it. This patch fixes the problem.
This case could occur for NFS over UDP mounts, where the server was
down for a few minutes under certain circumstances.
Reported by: bde
Tested by: bde
Reviewed by: gnn
MFC after: 2 weeks
during testing of network related changes where cached entries may pollute your
results, or during known congestion events where you don't want to unfairly
penalize hosts.
Prior to r232346 this would have meant you would break any connection with a sub
1500 MTU, as the hostcache was authoritative. All entries as they stand today
should simply be used to pre populate values for efficiency.
Submitted by: Jason Wolfe (j at nitrology dot com)
Reviewed by: rwatson, sbruno, rrs , bz (earlier version)
MFC after: 2 weeks
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D6198
Restructure code slightly to save ip_tos bits earlier. Fix the bug
where the ip_tos field is zeroed out before assigning to the iptos
variable. Restore the ip_tos and ip_ver fields only if they have
been zeroed during the pseudo-header checksum calculation.
Reviewed by: cem, gnn, hiren
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D8053
As a side effect of r261242 when using accept_filter the
first call to soisconnected() is done earlier in tcp_input()
instead of tcp_do_segment() context. Restore the expected behaviour.
Note: This call to soisconnected() seems to be extraneous in all
cases (with or without accept_filter). Will be addressed in a
separate commit.
PR: 212920
Reported by: Alexey
Tested by: Alexey, jch
Sponsored by: Verisign, Inc.
MFC after: 1 week
While here, prefer if_addrhead (FreeBSD) to if_addrlist (BSD compat) naming
for the interface address list in sctp_bsd_addr.c
Reviewed by: tuexen
Differential Revision: https://reviews.freebsd.org/D8051
Descriptor returned by accept(2) should inherits capabilities rights from
the listening socket.
PR: 201052
Reviewed by: emaste, jonathan
Discussed with: many
Differential Revision: https://reviews.freebsd.org/D7724
There were two bugs:
* There was an accounting bug resulting in reporting a too small a_rwnd.
* There are a bug when abandoning messages in the reassembly queue.
MFC after: 4 weeks
* TCP_KEEPINIT
* TCP_KEEPINTVL
* TCP_KEEPIDLE
* TCP_KEEPCNT
always always report the values currently used when getsockopt()
is used. This wasn't the case when the sysctl-inherited default
values where used.
Ensure that the IPPROTO_TCP level socket option TCP_INFO has the
TCPI_OPT_ECN flag set in the tcpi_options field when ECN support
has been negotiated successfully.
Reviewed by: rrs, jtl, hiren
MFC after: 1 month
Differential Revision: 7833
warning:
sys/netinet/igmp.c:546:21: error: implicit conversion from 'int' to 'char' changes value from 148 to -108 [-Werror,-Wconstant-conversion]
p->ipopt_list[0] = IPOPT_RA; /* Router Alert Option */
~ ^~~~~~~~
sys/netinet/ip.h:153:19: note: expanded from macro 'IPOPT_RA'
#define IPOPT_RA 148 /* router alert */
^~~
This is because ipopt_list is an array of char, so IPOPT_RA is wrapped
to a negative value. It would be nice to change ipopt_list to an array
of u_char, but it changes the signature of the public struct ipoption,
so add an explicit cast to suppress the warning.
Reviewed by: imp
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D7777
can be in after receiving a FIN.
FWIW, NetBSD has this change for quite some time.
This has been tested at Netflix and Limelight in production traffic.
Reported by: Sam Kumar <samkumar99 at gmail.com> on transport@
Reviewed by: rrs
MFC after: 4 weeks
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D7475
I-FORWARD-TSN chunk before any DATA or I-DATA chunk.
Thanks to Julian Cordes for finding this problem and prividing
packetdrill scripts to reporduce the issue.
MFC after: 3 days
tso_segsz pkthdr field during RX processing, and use the information in TCP for
more correct accounting and as a congestion control input. This is only a start,
and an audit of other uses for the data is left as future work.
Reviewed by: gallatin, rrs
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D7564
r304436 attempted to optimize the handling of incoming UDP packet by only
making an expensive call to in_broadcast() if the mbuf was marked as an
broadcast packet. Unfortunately, this cannot work in the case of point-to-
point L2 protocols like PPP, which have no notion of "broadcast".
Discussions on how to properly fix r304436 are ongoing, but in the meantime
disable the optimization to ensure that no existing network setups are broken.
Reported by: bms
First, keep a ref count on the stcb after looking it up, as
done in the other lookup cases.
Second, before looking again at sp, ensure that it is not
freed, because the assoc is about to be freed.
MFC after: 3 days
The default value of the tunable introduced in r304436 couldn't be
effectively overrided on VIMAGE kernels, because instead of being
accessed via the appropriate VNET() accessor macro, it was accessed
via the VNET_NAME() macro, which resolves to the (should-be) read-only
master template of initial values of per-VNET data. Hence, while the
value of udp_require_l2_bcast could be altered on per-VNET basis, the
code in udp_input() would ignore it as it would always read the default
value (one) from the VNET master template.
Silence from: rstone
in_broadcast() was iterating over the ifnet address list without
first taking an IF_ADDR_RLOCK. This could cause a panic if a
concurrent operation modified the list.
Reviewed by: bz
MFC after: 2 months
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D7227
in_broadcast() can be quite expensive, so skip calling it if the
incoming mbuf wasn't sent to a broadcast L2 address in the first
place.
Reviewed by: gnn
MFC after: 2 months
Sponsored by: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D7309
For almost every packet that is transmitted through ip_output(),
a call to in_broadcast() was made to decide if the destination
IP was a broadcast address. in_broadcast() iterates over the
ifnet's address to find a source IP matching the subnet of the
destination IP, and then checks if the IP is a broadcast in that
subnet.
This is completely redundant as we have already performed the
route lookup, so the source IP is already known. Just use that
address to directly check whether the destination IP is a
broadcast address or not.
MFC after: 2 months
Sponsored By: EMC / Isilon Storage Division
Differential Revision: https://reviews.freebsd.org/D7266
alternate TCP stack in other then the closed state (pre-listen/connect).
The idea is that *if* that is supported by the alternate stack, it
is asked if its ok to switch. If it approves the "handoff" then we
allow the switch to happen. Also the fini() function now gets a flag
to tell if you are switching away *or* the tcb is destroyed. The
init() call into the alternate stack is moved to the end so the
tcb is more fully formed before the init transpires.
Sponsored by: Netflix Inc.
Differential Revision: D6790
The module works together with ipfw(4) and implemented as its external
action module.
Stateless NAT64 registers external action with name nat64stl. This
keyword should be used to create NAT64 instance and to address this
instance in rules. Stateless NAT64 uses two lookup tables with mapped
IPv4->IPv6 and IPv6->IPv4 addresses to perform translation.
A configuration of instance should looks like this:
1. Create lookup tables:
# ipfw table T46 create type addr valtype ipv6
# ipfw table T64 create type addr valtype ipv4
2. Fill T46 and T64 tables.
3. Add rule to allow neighbor solicitation and advertisement:
# ipfw add allow icmp6 from any to any icmp6types 135,136
4. Create NAT64 instance:
# ipfw nat64stl NAT create table4 T46 table6 T64
5. Add rules that matches the traffic:
# ipfw add nat64stl NAT ip from any to table(T46)
# ipfw add nat64stl NAT ip from table(T64) to 64:ff9b::/96
6. Configure DNS64 for IPv6 clients and add route to 64:ff9b::/96
via NAT64 host.
Stateful NAT64 registers external action with name nat64lsn. The only
one option required to create nat64lsn instance - prefix4. It defines
the pool of IPv4 addresses used for translation.
A configuration of instance should looks like this:
1. Add rule to allow neighbor solicitation and advertisement:
# ipfw add allow icmp6 from any to any icmp6types 135,136
2. Create NAT64 instance:
# ipfw nat64lsn NAT create prefix4 A.B.C.D/28
3. Add rules that matches the traffic:
# ipfw add nat64lsn NAT ip from any to A.B.C.D/28
# ipfw add nat64lsn NAT ip6 from any to 64:ff9b::/96
4. Configure DNS64 for IPv6 clients and add route to 64:ff9b::/96
via NAT64 host.
Obtained from: Yandex LLC
Relnotes: yes
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D6434
