1. 24 Jan, 2017 1 commit
    • Yotam Gigi's avatar
      net: Introduce psample, a new genetlink channel for packet sampling · 6ae0a628
      Yotam Gigi authored
      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: default avatarYotam Gigi <yotamg@mellanox.com>
      Signed-off-by: default avatarJiri Pirko <jiri@mellanox.com>
      Reviewed-by: default avatarJamal Hadi Salim <jhs@mojatatu.com>
      Reviewed-by: default avatarSimon Horman <simon.horman@netronome.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6ae0a628