There was a problem testing accelleran cu + oai du + oai ue + rfsim
because accelleran cu configures sdap header for UL but not for DL
and our sdap implementation deals with either "no sdap header at all"
or "sdap headers for both UL and DL".
The code has been modified to deal with the other cases
("sdap header for UL but not DL" and "sdap header for DL but not UL").
has_sdapDLheader and has_sdapULheader have been removed, has_sdap
too, replaced by has_sdap_rx and has_sdap_tx, which makes the code
independant of ue or gnb and is, I think, clearer.
With this work, accelleran cu + oai du + oai ue + rfsim works. We
also have oai gnb + oai ue + rfsim functional for all cases of sdap
header configuration (this won't happen for users, the code of gnb has to
be modified to have sdap header for only ul or only dl). It also works
with a COTS UE for all cases of sdap configuration (again, this won't
happen for users, only "no sdap header" and "sdap headers for both
UL and DL" exist in oai gnb with the current code).
To have other cases, you can edit openair2/RRC/NR/rrc_gNB_radio_bearers.c
and search for NR_SDAP_Config__sdap_HeaderDL_present in there.
To enable sdap, run the gnb with the command line argument
--gNBs.[0].enable_sdap 1
There was a problem in rrc_gNB_process_NGAP_PDUSESSION_RELEASE_COMMAND()
where we PROTOCOL_CTXT_SET_BY_INSTANCE() that does not initialize
eNB_index leading to a crash later on in pdcp. So let's initialize
everything.
Plus, while we're here, use do { } while(0) in the macros, just to avoid
problems like:
if (condition)
macro;
Without do { } while(0) only the first statement of the macro is done
in the if. (Not sure if the code has the problem somewhere, but doesn't
hurt to fix.)
Not only the teid is received from the DU but also the IP address. We
have to use it too.
Also, don't connect the UDP socket. The parameter remote_s_address in the
configuration file must not be used, at least not for gtp-u because the
IP address is received from the DU (plus for later, for multiple DUs, it
won't work at all).
Bruno Mongazon-Cazavet