gnrc_sixlowpan_iphc.c: handle forwarded GNRC_NETTYPE_IPV6 packet #5232
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jnohlgard
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Type: bug
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This is ugly, but it fixes the symptom (forwarded packets have 0 length payload). The proper fix would probably be to mark the UDP header in the correct location and mark the remaining payload snip as NETTYPE_UNDEF or something. |
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@ReneHerthel maybe this is of interest for you |
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Tested it rebased to master with an ethos border router (sending UDP packets to and from the host system using netcat) and it worked. ACK and go when |
miri64
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CI: ready for build
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Let go of Travis (:
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(already corrected it ;-P) |
miri64
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Process: needs backport
miri64
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Process: needs backport
| if (udp->type == GNRC_NETTYPE_IPV6) { | ||
| /* forwarded ipv6 packet */ | ||
| size_t diff = sizeof(udp_hdr_t) - nhc_len; | ||
| for (int i = nhc_len; i < (udp->size - diff); i++) { |
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Apparently this is the line which is breaking Murdock, but it's strange that Murdock didn't show the error on this check... How can we proceed to this? should I only change the the type of int i to size_t i to make Murdock happy? Is this the real cause of Murdock failing everywhere?
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I think yes. I tried bisecting, #5044 was the commit that breaks compilation.
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Well, it's not really broken but it forces NHC to be included by default, on which Murdock fails as the variables are not of the same type. But for me a size_t i = ... is somehow weird though... But well, it should be fixed somehow.
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Alternatively, you can use unsigned i = ... ;-) The error is about signage.
adopted #4544
Forwarded packets are not split into multiple snips and the whole payload is left marked (incorrectly?) as
GNRC_NETTYPE_IPV6after decompressing the 6lowpan information. This patch makes the UDP header compression keep any trailing garbage/payload if the snip was not marked as an UDP header.This fix makes UDP NHC work for my test setup.