x->replay_esn is already checked in if clause,
so remove check and ident properly
Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
- minimal fixes to the packet layout to avoid the __packed attribute when not
needed
- new packet type called UNICAST_4ADDR: in this packet it is possible to find
both source and destination node (in the classic UNICAST header only the
destination field exists).
- a new feature: Distributed ARP Table (D.A.T.). It aims to reduce ARP lookups
latency by means of a simil-DHT approach.
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Merge tag 'batman-adv-for-davem' of git://git.open-mesh.org/linux-merge
Included changes:
- minimal fixes to the packet layout to avoid the __packed attribute when not
needed
- new packet type called UNICAST_4ADDR: in this packet it is possible to find
both source and destination node (in the classic UNICAST header only the
destination field exists).
- a new feature: Distributed ARP Table (D.A.T.). It aims to reduce ARP lookups
latency by means of a simil-DHT approach.
The tx data offset of packet mmap tx ring used to be :
(TPACKET2_HDRLEN - sizeof(struct sockaddr_ll))
The problem is that, with SOCK_RAW socket, the payload (14 bytes after
the beginning of the user data) is misaligned.
This patch allows to let the user gives an offset for it's tx data if
he desires.
Set sock option PACKET_TX_HAS_OFF to 1, then specify in each frame of
your tx ring tp_net for SOCK_DGRAM, or tp_mac for SOCK_RAW.
Signed-off-by: Paul Chavent <paul.chavent@onera.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
The "early client detection mechanism" can be extended to find new clients by
means of unicast_4addr packets.
The unicast_4addr packet contains as well as the broadcast packet (which is
currently used in this mechanism) the address of the originating node and can
therefore be used to install new entries in the Global Translation Table
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
This patch adds a runtime switch that enables the user to turn the DAT feature
on or off at runtime
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
This patch makes it possible to decide whether to include DAT within the
batman-adv binary or not.
It is extremely useful when the user wants to reduce the size of the resulting
module by cutting off any not needed feature.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
In case of an ARP message going in or out the soft_iface, it is intercepted and
a special action is performed. In particular the DHT helper functions previously
implemented are used to store all the ARP entries belonging to the network in
order to provide a fast and unicast lookup instead of the classic broadcast
flooding mechanism.
Each node stores the entries it is responsible for (following the DHT rules) in
its soft_iface ARP table. This makes it possible to reuse the kernel data
structures and functions for ARP management.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
ARP messages are now parsed to make it possible to trigger special actions
depending on their types (snooping).
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Since batman-adv cannot inter-operate with the host ARP table, this patch
introduces a batman-adv private storage for ARP entries exchanged within DAT.
This storage will represent the node local cache in the DAT protocol.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Add all the relevant functions in order to manage a Distributed Hash Table over
the B.A.T.M.A.N.-adv network. It will later be used to store several ARP entries
and implement DAT (Distributed ARP Table)
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
A new log level has been added to concentrate messages regarding DAT: ARP
snooping, requests, response and DHT related messages.
The new log level is named BATADV_DBG_DAT
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
The current unicast packet type does not contain the orig source address. This
patches add a new unicast packet (called UNICAST_4ADDR) which provides two new
fields: the originator source address and the subtype (the type of the data
contained in the packet payload). The former is useful to identify the node
which injected the packet into the network and the latter is useful to avoid
creating new unicast packet types in the future: a macro defining a new subtype
will be enough.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Headers which are already perfectly aligned and create a 4 byte boundary
non-ethernet header payload can have the __packed attribute removed. The
__packed attribute doesn't change the appeareance of the packet for these
headers because no extra padding is necessary to align the data members. The
compiler will also create slightly faster code for loads of multi-byte members.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
The ethernet header is 14 bytes long. Therefore, the data after it is not 4
byte aligned and may cause problems on systems without unaligned data access.
Reserving NET_IP_ALIGN more byes can fix the misalignment of the ethernet
header.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Commit 56b765b79e (htb: improved accuracy at high rates)
introduced two bugs :
1) one bstats_update() was inadvertently removed from
htb_dequeue_tree(), breaking statistics/rate estimation.
2) Missing qdisc_put_rtab() calls in htb_change_class(),
leaking kernel memory, now struct htb_class no longer
retains pointers to qdisc_rate_table structs.
Since only rate is used, dont use qdisc_get_rtab() calls
copying data we ignore anyway.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vimalkumar <j.vimal@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of issuing (0) statements when !CONFIG_SYSFS which will cause
'warning: ', we'll use inline statements instead. This will effectively
do the same thing, but suppress any unnecessary warnings.
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: bridge@lists.linux-foundation.org
Cc: netdev@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bridge notify hook rtnl_bridge_notify() was not handling the
case where the master flags was set or with both flags set. First
flags are not being passed correctly and second the logic to parse
them is broken.
This patch passes the original flags value and fixes the
logic.
Reported-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Current HTB (and TBF) uses rate table computed by the "tc"
userspace program, which has the following issue:
The rate table has 256 entries to map packet lengths
to token (time units). With TSO sized packets, the
256 entry granularity leads to loss/gain of rate,
making the token bucket inaccurate.
Thus, instead of relying on rate table, this patch
explicitly computes the time and accounts for packet
transmission times with nanosecond granularity.
This greatly improves accuracy of HTB with a wide
range of packet sizes.
Example:
tc qdisc add dev $dev root handle 1: \
htb default 1
tc class add dev $dev classid 1:1 parent 1: \
rate 5Gbit mtu 64k
Here is an example of inaccuracy:
$ iperf -c host -t 10 -i 1
With old htb:
eth4: 34.76 Mb/s In 5827.98 Mb/s Out - 65836.0 p/s In 481273.0 p/s Out
[SUM] 9.0-10.0 sec 669 MBytes 5.61 Gbits/sec
[SUM] 0.0-10.0 sec 6.50 GBytes 5.58 Gbits/sec
With new htb:
eth4: 28.36 Mb/s In 5208.06 Mb/s Out - 53704.0 p/s In 430076.0 p/s Out
[SUM] 9.0-10.0 sec 594 MBytes 4.98 Gbits/sec
[SUM] 0.0-10.0 sec 5.80 GBytes 4.98 Gbits/sec
The bits per second on the wire is still 5200Mb/s with new HTB
because qdisc accounts for packet length using skb->len, which
is smaller than total bytes on the wire if GSO is used. But
that is for another patch regardless of how time is accounted.
Many thanks to Eric Dumazet for review and feedback.
Signed-off-by: Vimalkumar <j.vimal@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As suggested by Eric, we could introduce a helper function
for ipv6 too, to avoid checking if rt is NULL before
dst_release().
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lots of points in the sctp_cmd_interpreter function treat the sctp_cmd_t arg as
a void pointer, even though they are written as various other types. Theres no
need for this as doing so just leads to possible type-punning issues that could
cause crashes, and if we remain type-consistent we can actually just remove the
void * member of the union entirely.
Change Notes:
v2)
* Dropped chunk that modified SCTP_NULL to create a marker pattern
should anyone try to use a SCTP_NULL() assigned sctp_arg_t, Assigning
to .zero provides the same effect and should be faster, per Vlad Y.
v3)
* Reverted part of V2, opting to use memset instead of .zero, so that
the entire union is initalized thus avoiding the i164 speculative load
problems previously encountered, per Dave M.. Also rewrote
SCTP_[NO]FORCE so as to use common infrastructure a little more
Signed-off-by: Neil Horman <nhorman@tuxdriver.com
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
In dev_forward_change(), it is useless to check if idev->dev
is NULL, it is always non-NULL here.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some years ago, the ktime_t helper functions ktime_now() and ktime_lt()
have been introduced. Instead of defining them inside pktgen.c, they
should either use ktime_t library functions or, if not available, they
should be defined in ktime.h, so that also others can benefit from them.
ktime_compare() is introduced with a similar notion as in timespec_compare().
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
For passive TCP connections using TCP_DEFER_ACCEPT facility,
we incorrectly increment req->retrans each time timeout triggers
while no SYNACK is sent.
SYNACK are not sent for TCP_DEFER_ACCEPT that were established (for
which we received the ACK from client). Only the last SYNACK is sent
so that we can receive again an ACK from client, to move the req into
accept queue. We plan to change this later to avoid the useless
retransmit (and potential problem as this SYNACK could be lost)
TCP_INFO later gives wrong information to user, claiming imaginary
retransmits.
Decouple req->retrans field into two independent fields :
num_retrans : number of retransmit
num_timeout : number of timeouts
num_timeout is the counter that is incremented at each timeout,
regardless of actual SYNACK being sent or not, and used to
compute the exponential timeout.
Introduce inet_rtx_syn_ack() helper to increment num_retrans
only if ->rtx_syn_ack() succeeded.
Use inet_rtx_syn_ack() from tcp_check_req() to increment num_retrans
when we re-send a SYNACK in answer to a (retransmitted) SYN.
Prior to this patch, we were not counting these retransmits.
Change tcp_v[46]_rtx_synack() to increment TCP_MIB_RETRANSSEGS
only if a synack packet was successfully queued.
Reported-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Vijay Subramanian <subramanian.vijay@gmail.com>
Cc: Elliott Hughes <enh@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit e5a55a8987 ('net: create generic
bridge ops') broke the handling of a non-zero starting index in
rtnl_bridge_getlink() (based on the old br_dump_ifinfo()).
When the starting index is non-zero, we need to increment the current
index for each entry that we are skipping. Also, we need to check the
index before both cases, since we may previously have stopped
iteration between getting information about a device from its master
and from itself.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Tested-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fib6_add_rt2node() will reject the nexthop if this flag is set, so
we perform the check only for the first nexthop.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since this array is no longer part of the bridge driver, it should
have an 'eth' prefix not 'br'.
We also assume that either it's 16-bit-aligned or the architecture has
efficient unaligned access. Ensure the first of these is true by
explicitly aligning it.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Function name should include '_ether_addr'.
Return type should be bool.
Parameter name should be 'addr' not 'dest' (also matching kernel-doc).
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Parse the string into an array of bytes rather than ints, so we can
use is_link_local() rather than reimplementing it.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Orphaning frags for zero copy skbs needs to allocate data in atomic
context so is has a chance to fail. If it does we currently discard
the skb which is safe, but we don't report anything to the caller,
so it can not recover by e.g. disabling zero copy.
Add an API to free skb reporting such errors: this is used
by tun in case orphaning frags fails.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Even if skb is marked for zero copy, net core might still decide
to copy it later which is somewhat slower than a copy in user context:
besides copying the data we need to pin/unpin the pages.
Add a parameter reporting such cases through zero copy callback:
if this happens a lot, device can take this into account
and switch to copying in user context.
This patch updates all users but ignores the passed value for now:
it will be used by follow-up patches.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
#if defined(CONFIG_FOO) || defined(CONFIG_FOO_MODULE)
can be replaced by
#if IS_ENABLED(CONFIG_FOO)
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
#if defined(CONFIG_FOO) || defined(CONFIG_FOO_MODULE)
can be replaced by
#if IS_ENABLED(CONFIG_FOO)
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The SO_ATTACH_FILTER option is set only. I propose to add the get
ability by using SO_ATTACH_FILTER in getsockopt. To be less
irritating to eyes the SO_GET_FILTER alias to it is declared. This
ability is required by checkpoint-restore project to be able to
save full state of a socket.
There are two issues with getting filter back.
First, kernel modifies the sock_filter->code on filter load, thus in
order to return the filter element back to user we have to decode it
into user-visible constants. Fortunately the modification in question
is interconvertible.
Second, the BPF_S_ALU_DIV_K code modifies the command argument k to
speed up the run-time division by doing kernel_k = reciprocal(user_k).
Bad news is that different user_k may result in same kernel_k, so we
can't get the original user_k back. Good news is that we don't have
to do it. What we need to is calculate a user2_k so, that
reciprocal(user2_k) == reciprocal(user_k) == kernel_k
i.e. if it's re-loaded back the compiled again value will be exactly
the same as it was. That said, the user2_k can be calculated like this
user2_k = reciprocal(kernel_k)
with an exception, that if kernel_k == 0, then user2_k == 1.
The optlen argument is treated like this -- when zero, kernel returns
the amount of sock_fprog elements in filter, otherwise it should be
large enough for the sock_fprog array.
changes since v1:
* Declared SO_GET_FILTER in all arch headers
* Added decode of vlan-tag codes
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jeff Kirsher says:
====================
This series contains updates to ixgbe, ixgbevf, igbvf, igb and
networking core (bridge). Most notably is the addition of support
for local link multicast addresses in SR-IOV mode to the networking
core.
Also note, the ixgbe patch "ixgbe: Add support for pipeline reset" and
"ixgbe: Fix return value from macvlan filter function" is revised based
on community feedback.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
BPF filters lack ability to access skb->vlan_tci
This patch adds two new ancillary accessors :
SKF_AD_VLAN_TAG (44) mapped to vlan_tx_tag_get(skb)
SKF_AD_VLAN_TAG_PRESENT (48) mapped to vlan_tx_tag_present(skb)
This allows libpcap/tcpdump to use a kernel filter instead of
having to fallback to accept all packets, then filter them in
user space.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Ani Sinha <ani@aristanetworks.com>
Suggested-by: Daniel Borkmann <danborkmann@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
- some code cleanups and minor fixes (3 of them were reported by Coverity)
- 'struct hard_iface' re-shaping to improve multi-protocol support
- ECTP packets silent drop
- transfer the WIFI flag on clients in case of roaming
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Merge tag 'batman-adv-for-davem' of git://git.open-mesh.org/linux-merge
included changes:
- some code cleanups and minor fixes (3 of them were reported by Coverity)
- 'struct hard_iface' re-shaping to improve multi-protocol support
- ECTP packets silent drop
- transfer the WIFI flag on clients in case of roaming
adds a "hwaddr" to the "IP-Config: Complete" KERN_INFO message
with the dev_addr of the device selected for auto configuration.
Signed-off-by: Claudio Fontana <claudio.fontana@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds support for the net device ops to manage the embedded
hardware bridge on ixgbe devices. With this patch the bridge
mode can be toggled between VEB and VEPA to support stacking
macvlan devices or using the embedded switch without any SW
component in 802.1Qbg/br environments.
Additionally, this adds source address pruning to the ixgbevf
driver to prune any frames sent back from a reflective relay on
the switch. This is required because the existing hardware does
not support this. Without it frames get pushed into the stack
with its own src mac which is invalid per 802.1Qbg VEPA
definition.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hardware switches may support enabling and disabling the
loopback switch which puts the device in a VEPA mode defined
in the IEEE 802.1Qbg specification. In this mode frames are
not switched in the hardware but sent directly to the switch.
SR-IOV capable NICs will likely support this mode I am
aware of at least two such devices. Also I am told (but don't
have any of this hardware available) that there are devices
that only support VEPA modes. In these cases it is important
at a minimum to be able to query these attributes.
This patch adds an additional IFLA_BRIDGE_MODE attribute that can be
set and dumped via the PF_BRIDGE:{SET|GET}LINK operations. Also
anticipating bridge attributes that may be common for both embedded
bridges and software bridges this adds a flags attribute
IFLA_BRIDGE_FLAGS currently used to determine if the command or event
is being generated to/from an embedded bridge or software bridge.
Finally, the event generation is pulled out of the bridge module and
into rtnetlink proper.
For example using the macvlan driver in VEPA mode on top of
an embedded switch requires putting the embedded switch into
a VEPA mode to get the expected results.
-------- --------
| VEPA | | VEPA | <-- macvlan vepa edge relays
-------- --------
| |
| |
------------------
| VEPA | <-- embedded switch in NIC
------------------
|
|
-------------------
| external switch | <-- shiny new physical
------------------- switch with VEPA support
A packet sent from the macvlan VEPA at the top could be
loopbacked on the embedded switch and never seen by the
external switch. So in order for this to work the embedded
switch needs to be set in the VEPA state via the above
described commands.
By making these attributes nested in IFLA_AF_SPEC we allow
future extensions to be made as needed.
CC: Lennert Buytenhek <buytenh@wantstofly.org>
CC: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PF_BRIDGE:RTM_{GET|SET}LINK nlmsg family and type are
currently embedded in the ./net/bridge module. This prohibits
them from being used by other bridging devices. One example
of this being hardware that has embedded bridging components.
In order to use these nlmsg types more generically this patch
adds two net_device_ops hooks. One to set link bridge attributes
and another to dump the current bride attributes.
ndo_bridge_setlink()
ndo_bridge_getlink()
CC: Lennert Buytenhek <buytenh@wantstofly.org>
CC: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In SR-IOV mode the PF driver acts as the uplink port and is
used to send control packets e.g. lldpad, stp, etc.
eth0.1 eth0.2 eth0
VF VF PF
| | | <-- stand-in for uplink
| | |
--------------------------
| Embedded Switch |
--------------------------
|
MAC <-- uplink
But the embedded switch is setup to forward multicast addresses
to all interfaces both VFs and PF and onto the physical link.
This results in reserved MAC addresses used by control protocols
to be forwarded over the switch onto the VF.
In the LLDP case the PF sends an LLDPDU and it is currently
being forwarded to all the VFs who then see the PF as a peer.
This is incorrect.
This patch adds the multicast addresses to the RAR table in the
hardware to prevent this behavior.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
in case of client roaming a new global entry is added while a corresponding
local one is still present. In this case the node can safely pass the WIFI flag
from the local to the global entry.
This change is required to let the AP-isolation correctly working in case of
roaming: if a generic WIFI client C roams from node A to B, A adds a global
entry for C without adding any WIFI flag. The latter will be set only later,
once A has received C's advertisement from B. In this time period the
AP-Isolation (if enabled) would not correctly work since C is not marked as
WIFI, so allowing it to communicate with other WIFI clients.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
In order to properly convert a bitwise AND to a boolean value, the whole
expression must be prepended by "!!".
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
In batadv_check_unicast_ttvn() the code accesses both the unicast header and the
Ethernet header in the payload. For this reason pskb_may_pull() must be invoked
to check for the required space.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Shan Wei