On 28 July 2016 at 23:45, Leon George <l...@georgemail.eu> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA256 > > Hi :-) > > The UDP checksum for outgoing L2TP datagrams seems to be broken. > It has been tested with TP-LINK's WR842n, WDR3600, and WDR4300. > On two normal Linux computers it's working. > > We've tried disabling UDP offloading using ethtool without success. > > Is there any way we can make OpenWRT emit the datagrams with the > checksum in place? > > This shows up in Wireshark. The first two datagrams are being received > on the other side. The ones after the l2tp aren't. > > #this is received on the other end. normal udp > 14.6944 UDP 575 52958 → 53201 Len=513 > 14.8159 UDP 152 53201 → 52958 Len=90 > #ip l2tp add tunnel tunnel_id 52958 peer_tunnel_id 53201 encap udp > local '2001:920:18ae:3:20b:c0ff:fe46:42b0' udp_sport 52958 remote > '2a03:b0c0:3:d0::bb5:6001' udp_dport 53201 > 14.9130 UDP 184 52958 → 53201 Len=122 [ILLEGAL CHECKSUM (0)] > 15.3230 UDP 152 52958 → 53201 Len=90 [ILLEGAL CHECKSUM (0)] > 15.6929 UDP 184 52958 → 53201 Len=122 [ILLEGAL CHECKSUM (0)] > 15.8198 UDP 164 53201 → 52958 Len=102 > > hoping somebody has an idea :-)
You may want to apply this kernel patch: https://github.com/torvalds/linux/commit/018f8258582381bcce484312f0e9ec2970d0383e yousong > > cu, > Leon > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v2 > > iQEwBAEBCAAaBQJXmiiKExxsZW9uQGdlb3JnZW1haWwuZXUACgkQ8ibA0ZlHqfFq > nAf/euEN7F1A80U8c6J4NE89qHiA98Nzjf1GorjhlOL5H2qQivxLp82ETQmJdUPt > fzOqpOT3T2bCeR2G0HBtFVMvaHm5fc2cua2hguo+53NFR1oBHl85jsW9zt+AzIaD > LPoi1nJqcLzLj7JjjYkoR8RIfBU8stq3YgLM78tvOKHmO/RYHbgOosJaIrgH2vZM > VvBRLe6ro+snHrYeko570uke+M3/sURhFjL8wWKqzwqr/RGF0H4oF+X06/f1VB9J > TLF/eA1JGTlL5RrjTZ6xVE2qFSa0uzNMtP3RgjRlBQj1tq1+AScRkn6loQ6bkKY8 > MrbZSB0dURwCKNQ8P2sAVQzccw== > =2r70 > -----END PGP SIGNATURE----- > _______________________________________________ > openwrt-devel mailing list > openwrt-devel@lists.openwrt.org > https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel _______________________________________________ openwrt-devel mailing list openwrt-devel@lists.openwrt.org https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-devel
