Performs reverse path filtering (RPF) on IPv6 packets as per RFC 3704.
Possible values:
"strict" : Performs "strict" filtering as per RFC 3704. This check verifies that the in ingress interface is the same interface that would be used to send a packet reply to the source. That is, ingress == egress.
"loose" : Performs "loose" filtering as per RFC 3704. This check only verifies that there is a route back to the source through any interface; even if it's not the same one on which the packet arrived.
"strict-forward" : This is almost identical to "strict", but does not perform RPF for packets targeted to the host (INPUT).
"loose-forward" : This is almost identical to "loose", but does not perform RPF for packets targeted to the host (INPUT).
"no" : RPF is completely disabled.
The rp_filter for IPv4 is controlled using sysctl.
one of "strict", "loose", "strict-forward", "loose-forward", "no""strict"