Add a general way for kernel modules to sample packets, without being tied
to any specific subsystem. This netlink channel can be used by tc,
iptables, etc. and allow to standardize packet sampling in the kernel.
For every sampled packet, the psample module adds the following metadata
fields:
PSAMPLE_ATTR_IIFINDEX - the packets input ifindex, if applicable
PSAMPLE_ATTR_OIFINDEX - the packet output ifindex, if applicable
PSAMPLE_ATTR_ORIGSIZE - the packet's original size, in case it has been
truncated during sampling
PSAMPLE_ATTR_SAMPLE_GROUP - the packet's sample group, which is set by the
user who initiated the sampling. This field allows the user to
differentiate between several samplers working simultaneously and
filter packets relevant to him
PSAMPLE_ATTR_GROUP_SEQ - sequence counter of last sent packet. The
sequence is kept for each group
PSAMPLE_ATTR_SAMPLE_RATE - the sampling rate used for sampling the packets
PSAMPLE_ATTR_DATA - the actual packet bits
The sampled packets are sent to the PSAMPLE_NL_MCGRP_SAMPLE multicast
group. In addition, add the GET_GROUPS netlink command which allows the
user to see the current sample groups, their refcount and sequence number.
This command currently supports only netlink dump mode.
Signed-off-by: Yotam Gigi <yotamg@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
