c06d313d86
Currently man 8 tc-skbmod says that "...the swap action will occur after
any smac/dmac substitutions are executed, if they are present."
This is false. In fact, trying to "set" and "swap" in a single skbmod
command causes the "set" part to be completely ignored. As an example:
$ tc filter add dev eth0 parent 1: protocol ip prio 10 \
matchall action skbmod \
set dmac AA:AA:AA:AA:AA:AA smac BB:BB:BB:BB:BB:BB \
swap mac
The above command simply does a "swap", without setting DMAC or SMAC to
AA's or BB's. The root cause of this is in the kernel, see
net/sched/act_skbmod.c:tcf_skbmod_init():
parm = nla_data(tb[TCA_SKBMOD_PARMS]);
index = parm->index;
if (parm->flags & SKBMOD_F_SWAPMAC)
lflags = SKBMOD_F_SWAPMAC;
^^^^^^^^^^^^^^^^^^^^^^^^^^
Doing a "=" instead of "|=" clears all other "set" flags when doing a
"swap". Discourage using "set" and "swap" in the same command by
documenting it as undefined behavior, and update the "SYNOPSIS" section
as well as tc -help text accordingly.
If one really needs to e.g. "set" DMAC to all AA's then "swap" DMAC and
SMAC, one should do two separate commands and "pipe" them together.
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
|
||
|---|---|---|
| bash-completion | ||
| bridge | ||
| dcb | ||
| devlink | ||
| doc/actions | ||
| etc/iproute2 | ||
| examples/bpf | ||
| genl | ||
| include | ||
| ip | ||
| lib | ||
| man | ||
| misc | ||
| netem | ||
| rdma | ||
| schema | ||
| tc | ||
| testsuite | ||
| tipc | ||
| vdpa | ||
| .clang-format | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| Makefile | ||
| README | ||
| README.devel | ||
| configure | ||
README
This is a set of utilities for Linux networking.
Information:
https://wiki.linuxfoundation.org/networking/iproute2
Download:
http://www.kernel.org/pub/linux/utils/net/iproute2/
Stable version repository:
git://git.kernel.org/pub/scm/network/iproute2/iproute2.git
Development repository:
git://git.kernel.org/pub/scm/network/iproute2/iproute2-next.git
How to compile this.
--------------------
1. libdbm
arpd needs to have the berkeleydb development libraries. For Debian
users this is the package with a name like libdbX.X-dev.
DBM_INCLUDE points to the directory with db_185.h which
is the include file used by arpd to get to the old format Berkeley
database routines. Often this is in the db-devel package.
2. make
The makefile will automatically build a config.mk file which
contains definitions of libraries that may or may not be available
on the system such as: ATM, ELF, MNL, and SELINUX.
3. include/uapi
This package includes matching sanitized kernel headers because
the build environment may not have up to date versions. See Makefile
if you have special requirements and need to point at different
kernel include files.
Stephen Hemminger
stephen@networkplumber.org
Alexey Kuznetsov
kuznet@ms2.inr.ac.ru