libosmogsm is a new library that is distributed in the libosmocore.
Now, openbsc depends on it. This patch gets openbsc with this
change.
This patch also rewrites all include path to the new
osmocom/[gsm|core]
Signed-off-by: Pablo Neira Ayuso <pablo@gnumonks.org>
When we copy a msgb, we need to make sure the msgb_cb->bssgp_cell_id
pointer points to data in the new message, not in the old message.
Thanks to Dieter Spaar for spotting this.
As we only have one NS-VC between gb_proxy and SGSN, we cannot
forward a NS-BLOCK from the BSS to the SGSN, as it would affect
all other BSS's, too.
Thus, we check if we have an unblocked PTP-BVC in the NSVC to the BSS,
and then issue a BVC-BLOCK towards the SGSN.
This should prevent any further PDU's from the SGSN to be sent to
this BSS.
The reason for this is quite simple: We want to make sure anyone
running a customized version of OpenBSC to operate a network will
have to release all custom modifiations to the source code.
Right now the memcpy with the data will copy data to itself as
the new_msg->data and msg->data are the same due the previous
copying of the header which included copying the list entry..
We allocate a message as big as the current one, then we have to
set all pointers by looking of how far they are away from the
msg->_data and add that to the new pointers.
Also copy the OpenBSC/GPRS specific CB data, also do the same
for calculating the offset to the data... At the end we should
end up with a copy...
Some BSS that connect to the proxy do not continue to perform the
RESET procedure after a timeout. In order to resurrect them, we
simply start a RESET procedure.
As only NS-UNITDATA messages are ever passed into the Gb Proxy,
we need to do the msgb_free() at a much higher point in the calling
stack, i.e. inside the NS protocol layer. This means it is now
the same logic as in OpenBSC itself.
The old idea was to take a msgb from gbprox_rcvmsg() and then
modify it and finally send it all the way down to nsip_sendmsg()
to the remote peer.
However, this introduces memory management difficulties, as we then
have to distinguish three cases:
* msgb was sent to a remote peer
* we sent some error message and need to free the msgb
* we need to make n-1 copies in case of a BSSVC-RESET from the SGSN
So instead we now simply always copy the message if we pass it on.
All messages received by gbprox_rcvmsg() are msgb_free()d in the very
same routine
All messages allocated by tx2peer() or tx2sgsn() are freed after
nsip_sendmsg()
If a PTP BVC is BVC-RESET by the BSS, the PDU contains the
Cell Identifier. We can snoop this into our gbprox_peer structure
for better visualization of each peer in they vty.
In order to reuse the existing bssgp_tx_* functions without pulling
in the dependencies of gprs_bssgp.c, we have to move those functions
to gprs_bssgp_util.c
Furthermore, we can remove gbprox_nsi and replace it with bssgp_nsi,
and we can do proper processing of BVC-RESET messages coming from
the SGSN on the signalling BVC. In that case we need to send RESET
messages to all the BSS.
Harald Welte
Holger Hans Peter Freyther