HW drivers will use the header-type and command fields from the extended
keys, and some fields (e.g mask, val, offset) from the legacy keys.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: NHadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

This command could be useful to inc/dec fields.

For example, to forward any TCP packet and decrease its TTL:
$ tc filter add dev enp0s9 protocol ip parent ffff: \
    flower ip_proto tcp \
    action pedit munge ip ttl add 0xff pipe \
    action mirred egress redirect dev veth0

In the example above, adding 0xff to this u8 field is actually
decreasing it by one, since the operation is masked.
Signed-off-by: NAmir Vadai <amir@vadai.me>
Reviewed-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Extend pedit to enable the user setting offset relative to network
headers. This change would enable to work with more complex header
schemes (vs the simple IPv4 case) where setting a fixed offset relative
to the network header is not enough.

After this patch, the action has information about the exact header type
and field inside this header. This information could be used later on
for hardware offloading of pedit.

Backward compatibility was being kept:
1. Old kernel <-> new userspace
2. New kernel <-> old userspace
3. add rule using new userspace <-> dump using old userspace
4. add rule using old userspace <-> dump using new userspace

When using the extended api, new netlink attributes are being used. This
way, operation will fail in (1) and (3) - and no malformed rule be added
or dumped. Of course, new user space that doesn't need the new
functionality can use the old netlink attributes and operation will
succeed.
Since action can support both api's, (2) should work, and it is easy to
write the new user space to have (4) work.

The action is having a strict check that only header types and commands
it can handle are accepted. This way future additions will be much
easier.

Usage example:
$ tc filter add dev enp0s9 protocol ip parent ffff: \
  flower \
    ip_proto tcp \
    dst_port 80 \
  action pedit munge tcp dport set 8080 pipe \
  action mirred egress redirect dev veth0

Will forward tcp port whose original dest port is 80, while modifying
the destination port to 8080.
Signed-off-by: NAmir Vadai <amir@vadai.me>
Reviewed-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After the previous patch, struct tc_action should be enough
to represent the generic tc action, tcf_common is not necessary
any more. This patch gets rid of it to make tc action code
more readable.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

struct tc_action is confusing, currently we use it for two purposes:
1) Pass in arguments and carry out results from helper functions
2) A generic representation for tc actions

The first one is error-prone, since we need to make sure we don't
miss anything. This patch aims to get rid of this use, by moving
tc_action into tcf_common, so that they are allocated together
in hashtable and can be cast'ed easily.

And together with the following patch, we could really make
tc_action a generic representation for all tc actions and each
type of action can inherit from it.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now we can totally hide it from modules. tcf_hash_*() API's
will operate on struct tc_action, modules don't need to care about
the details.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This was simply making templates of functions and mostly causing a lot
of code duplication in the classifier action modules.

We solve this more cleanly by having a common "struct tcf_common" that
hash worker functions contained once in act_api.c can work with.

Callers work with real action objects that have the common struct
plus their module specific struct members.  You go from a common
object to the higher level one using a "to_foo()" macro which makes
use of container_of() to do the dirty work.

This also kills off act_generic.h which was only used by act_simple.c
and keeping it around was more work than the it's value.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!