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P25P1 SUID Continuation Messages & Accordian Encryption Error #2013

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@DSheirer

Description

@DSheirer

sdrtrunk Version
master.

Describe the bug
The current approach to reassembling FQSUID messages doesn't handle instances where a TDULC is transmitted that needs an extension and that extension is transmitted in an LDU1 message with an HDU transmitted in between. The current approach to holding and joining the extension message results in the HDU triggering a call start and then the latent TDULC gets the extension from the LDU1, gets processed, and causes the call event to close and subsequently, the LDU1 doesn't trigger a call start. Observed on a Harris Phase 1 system recording.

On some Harris console transmissions, the LDU2 encryption sync can sometimes incorrectly signal that Accordion encryption is being used and that causes the call to be flagged as encrypted. However, in these instances, the algorithm ID, key ID and MI are all zero. The Accordion algorithm ID is zero and the Unencrypted algorithm ID is 0x80, a one bit differance. Detect this situation and override the algorithm ID with a value of 0x80 to indicate unencrypted.

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