Hi Liping, On Thu, Mar 2, 2017 at 7:18 PM, Liping Zhang <zlpnobody@xxxxxxxxx> wrote: > Hi, > 2017-03-02 18:18 GMT+08:00 Gao Feng <fgao@xxxxxxxxxx>: > [...] >> The expect class is NF_CT_EXPECT_CLASS_DEFAULT, and proto is >> IPPROTO_UDP at the function "expect_rtp_rtcp", >> And it makes sure the port is even number. >> >> But look at the process_gcf, the port is got from the packet data at >> function get_h225_addr. >> So it may be odd number. >> It also would add one expect node whose class is >> NF_CT_EXPECT_CLASS_DEFAULT, and proto is IPPROTO_UDP. > > The nat_rtp_rtcp() is only invoked by expect_rtp_rtcp, and nf_nat_sdp_media() > is only invoked by set_expected_rtp_rtcp. So the RTP port is ensured to be > even, as well as the rtp_exp->tuple.dst.u.udp.port. > > Note: the rtp_exp is alloced by nf_ct_expect_alloc, and initialized by > nf_ct_expect_init, then passed to nat_rtp_rtcp or nf_nat_sdp_media. > > So I cannot figure out why process_gcf will affect this? Or I missed something? > I was lost in codes and forgot to check the caller of nat_rtp_rtcp. Thanks your explanations. There is no any issue in current codes indeed. Best Regards Feng -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
