linux-toradex.git/include/net/protocol.h, branch v4.16-rc4

IPv4: early demux can return an error code

2017-10-01T02:55:47+00:00

Currently no error is emitted, but this infrastructure will
used by the next patch to allow source address validation
for mcast sockets.
Since early demux can do a route lookup and an ipv4 route
lookup can return an error code this is consistent with the
current ipv4 route infrastructure.

Signed-off-by: Paolo Abeni 
Signed-off-by: David S. Miller

net: Add sysctl to toggle early demux for tcp and udp

2017-03-24T20:17:07+00:00

Certain system process significant unconnected UDP workload.
It would be preferrable to disable UDP early demux for those systems
and enable it for TCP only.

By disabling UDP demux, we see these slight gains on an ARM64 system-
782 -> 788Mbps unconnected single stream UDPv4
633 -> 654Mbps unconnected UDPv4 different sources

The performance impact can change based on CPU architecure and cache
sizes. There will not much difference seen if entire UDP hash table
is in cache.

Both sysctls are enabled by default to preserve existing behavior.

v1->v2: Change function pointer instead of adding conditional as
suggested by Stephen.

v2->v3: Read once in callers to avoid issues due to compiler
optimizations. Also update commit message with the tests.

v3->v4: Store and use read once result instead of querying pointer
again incorrectly.

v4->v5: Refactor to avoid errors due to compilation with IPV6={m,n}

Signed-off-by: Subash Abhinov Kasiviswanathan 
Suggested-by: Eric Dumazet 
Cc: Stephen Hemminger 
Cc: Tom Herbert 
Cc: David Miller 
Signed-off-by: David S. Miller

udp: Remove udp_offloads

2016-04-07T20:53:30+00:00

Now that the UDP encapsulation GRO functions have been moved to the UDP
socket we not longer need the udp_offload insfrastructure so removing it.

Signed-off-by: Tom Herbert 
Signed-off-by: David S. Miller

udp: restrict offloads to one namespace

2016-01-10T22:28:24+00:00

udp tunnel offloads tend to aggregate datagrams based on inner
headers. gro engine gets notified by tunnel implementations about
possible offloads. The match is solely based on the port number.

Imagine a tunnel bound to port 53, the offloading will look into all
DNS packets and tries to aggregate them based on the inner data found
within. This could lead to data corruption and malformed DNS packets.

While this patch minimizes the problem and helps an administrator to find
the issue by querying ip tunnel/fou, a better way would be to match on
the specific destination ip address so if a user space socket is bound
to the same address it will conflict.

Cc: Tom Herbert 
Cc: Eric Dumazet 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

net: Eliminate no_check from protosw

2014-05-23T20:28:53+00:00

It doesn't seem like an protocols are setting anything other
than the default, and allowing to arbitrarily disable checksums
for a whole protocol seems dangerous. This can be done on a per
socket basis.

Signed-off-by: Tom Herbert 
Signed-off-by: David S. Miller

net: Add GRO support for UDP encapsulating protocols

2014-01-22T02:05:04+00:00

Add GRO handlers for protocols that do UDP encapsulation, with the intent of
being able to coalesce packets which encapsulate packets belonging to
the same TCP session.

For GRO purposes, the destination UDP port takes the role of the ether type
field in the ethernet header or the next protocol in the IP header.

The UDP GRO handler will only attempt to coalesce packets whose destination
port is registered to have gro handler.

Use a mark on the skb GRO CB data to disallow (flush) running the udp gro receive
code twice on a packet. This solves the problem of udp encapsulated packets whose
inner VM packet is udp and happen to carry a port which has registered offloads.

Signed-off-by: Shlomo Pongratz 
Signed-off-by: Or Gerlitz 
Signed-off-by: David S. Miller

ipv4: introduce hardened ip_no_pmtu_disc mode

2014-01-13T19:22:55+00:00

This new ip_no_pmtu_disc mode only allowes fragmentation-needed errors
to be honored by protocols which do more stringent validation on the
ICMP's packet payload. This knob is useful for people who e.g. want to
run an unmodified DNS server in a namespace where they need to use pmtu
for TCP connections (as they are used for zone transfers or fallback
for requests) but don't want to use possibly spoofed UDP pmtu information.

Currently the whitelisted protocols are TCP, SCTP and DCCP as they check
if the returned packet is in the window or if the association is valid.

Cc: Eric Dumazet 
Cc: David Miller 
Cc: John Heffner 
Suggested-by: Florian Weimer 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

protocol.h: Remove extern from function prototypes

2013-09-23T05:51:08+00:00

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: Joe Perches 
Signed-off-by: David S. Miller

net: Remove code duplication between offload structures

2012-11-15T22:39:51+00:00

Move the offload callbacks into its own structure.

Signed-off-by: Vlad Yasevich 
Signed-off-by: David S. Miller

ipv6: Pull IPv6 GSO registration out of the module

2012-11-15T22:39:24+00:00

Sing GSO support is now separate, pull it out of the module
and make it its own init call.
Remove the cleanup functions as they are no longer called.

Signed-off-by: Vlad Yasevich 
Signed-off-by: David S. Miller