From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tushar Dave <tushar.n.dave@oracle.com>
Subject: Query: eBPF socket filter
Date: Fri, 20 Apr 2018 23:18:01 -0700
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Hi,

I am dealing with Reliable Datagram Socket (RDS) protocol and exploring
ways to filter RDS traffic using eBPF.

FYI, RDS sits on top of transport layer and works with
transport such as TCP and IB/RDMA. So RDS messages arrive in form of skb
(over TCP)and scatterlist (over IB/RDMA).

For RDS traffic over TCP, I am using ebpf program of type
BPF_PROG_TYPE_SOCKET_FILTER and with that my filter program receives
__sk_buff as bpf context. This works.
However, I cannot use BPF_PROG_TYPE_SOCKET_FILTER with struct
scatterlist. I am not sure if it would be appropriate to extend BPF
socket filter so that it also work with struct scatterlist?

Ideas/suggestions or any other alternatives please?

Thanks in advance,
-Tushar