[Bug]: HopStart not populated

[mrx23dot]

Category

Other

Hardware

Not Applicable

Firmware Version

?unknown sender version

Description

A HeltecV3 received

then it relayed it as:
ff ff ff ff 7c 1e e5 e2 9c 20 3c 52 03 08 00 00 63 8c 48 c1 09 ad cc 0d d8 67 35 47 b6 1e 06 e1 01 5b ea 72 23

based on protocol
https://meshtastic.org/docs/overview/mesh-algo/#packet-header-flags
[12]=(0x03) is Packet Header
HopLimit = 3 // 4-1 ok
HopStart = 0 (original HopLimit) why isn't this populated via originator fw? should be 4..7

I assume other unknown node also uses meshtastic fw, but I don't know which version.

Relevant log output

No response

[mrx23dot]

It's important to know intention, ie 7 means it is longrange msg

It would also help to see raw hex dump for received msgs in Debug window.

sure, not every msg is incorrect, not sure if it's correct on the head or not.

[GUVWAF]

hopStart was added in 2.3. The transmitter and all nodes on the path towards you need at least this firmware version, otherwise it will get lost.

[mrx23dot]

What about first receiving node running new fw populating it with received hopcount?
It's still more meaningful than leaving it at 0.

[GUVWAF]

Then it would be incorrect when there are multiple nodes with old firmware on the path.

[mrx23dot]

But old nodes worst case override our implied hopStart back to zero,
it's a best effort estimation of what the original value was (can only get lower), it might/it might not propagate to the edge.

[GUVWAF]

I'd prefer being sure it's either correct data or no available data above not knowing for sure whether it's incorrect or not.

That said, please encourage your mesh users to update their firmware instead.