In case of handover (but probably on RACH) we would send a RLL for
SAPI=0 even if this SAPI was never established. After we have released
all SAPI>0 locally check that SAPI=0 is established and if not release
the rf channel directly.
T3109 is started when the SACCH is deactivated. It is stopped when
the phones sends the DISC/UA/UM on LAPDm for the main signalling
link. In case of timeout the abnormal release procedure will be
initiated. Make sure to not issue the SACCH Deactivate twice to
avoid confusing the equipment.
This is still not fully spec compliant. In case of a timeout the
abnormal release handling will be started which involves starting
T3111+2. The error handling should be split out of the rf channel
release method, e.g. lchan_release should be called and check if
the channel release was already initiated.
If the CHAN ACTIV is NACKED we set the state backto NONE. This is
problematic as our channel allocator will allocate from the front
or from the back and if the channel is early in the list it might
cause permanent failures. Introduce a BROKEN state and use it when
the channel activation is failing for an unknown reason. Copy the
cause so it can be inspected later.
Deactivate the SACCH and release all SAPIs locally as of GSM 04.08. Add
documentation to the code and explain what will happen as part of the
release process.
* Release all channels with SAPI > 0 with the "local end release"
(as of NOTE 1 of GSM 04.08).
* No need to wait for all SAPIs to be torn down and the normal
REL_IND/REL_CONF will call rsl_handle_release and the channel
should be released.
* Update the documentation
Put the idiom that sets the lchan state to none and respecting the
error state into a shared method. This way the special handling for
the abnormal case is just in one place.
Avoid printing error messages when paging while the BTS is down. In
case a BTS is going down it is best to just let the timers expire
normally. We can not expire them right away as multiple BTS could be
paged and we do not want to interfere with that. There is no need to
stop the queue right now.
If subscriber A is calling B and has sent a CC Setup message we will
allocate the MO and MT transaction and link them together. When the
BTS or the lchan is failing the BSC API will send a clear request,
as part of the clear request all pending transactions will be released.
As part of taking down the transaction, the remote leg will be informed
and will send a MNCC_REL_REQ. This results in a call to trans_free. The
llist_for_each_entry_safe does not handle removing other elements from
the list and we would segfault.
One way to fix this is to move the transaction list into the subscriber
connection. This might require to create the subscriber connection for
MT handling earlier. Otherwise one could have one transaction list inside
the subscriber connection and a global list for MT- transactions.
This has been reported and analyzed by Tobias Engel. The IMSI Detach
is dispatched as part of the complete layer3 message. I had patched
the code to release the anchor and call msc_release_connection to
release the connection as fast as possible (otherwise the anchor would
trigger in a couple of seconds).
With commit 70ae5d3000 I made this more
generic to release the connection immediately if there are no operations,
no transaction and no silent call. This leads to the subscriber connection
being released twice and eventually causing a segfault. Remove the
msc_release_connection invocation from the IMSI Detach code as the connection
will be taken down by the BSC API.
This has been tested using the FakeBTS and an IMSI Detach message. The
channel is released immediately and the nitb does not crash.
GCC 3.x on PowerPC correctly highlights that the code is fishy.
Re-reading the RFC 3550 shows that we should subtract it and then
we are in the 16bit range. The probation and re-sync code is still
missing.
GCC:
mgcp/mgcp_network.c:200: warning: comparison is always true due to limited range of data type
MGCP is used over UDP and a response might be lost. The MGCP RFC
asks for keeping a list of responses and then using the previous
response to answer a duplicate request. I tried to conserve memory
and just wanted to remember the last transaction identifier and
result-code and re-generate the result from that. This made the
code look bad and this is why the entire response will now be stored.
It sadly increases the memory usage but can not be avoided at this
time.
Remove the msg->l3h pointer for the RQNT callback as strtok has
modified the content of it.
Rebased, tested and fixed by Holger Freyther. Release the transaction
only once the SMC is asking for the release and set the cb's to NULL
to catch a use after free early.
This has been rebased and fixed by Holger Freyther. The change of
the debug area was split out in a previous commit and the is_mt was
put back into the transaction code.
The transaction is now freed from the RELEASE_REQ sent by the SMC
layer and not inside the error path. When clearing the SMC instance
we also clear the callbacks.
This should and does happen as part of the trans_free/msc_release_connection
code. There is no easy way to determine that the lchan is now 'free' for other
things.. Let the transaction code sort this out. This code just needs to make
sure that transactions are always freed.
This is more a work around and one still needs to implement a
proper dispatch on the opening of the connection. If there is no
operation left, no transaction and no silent call, close down the
channel.
Use the code that is shipped inside the libosmogsm library. Right now
the signature (besides the static) and the implementation is the same.
This makes using the libosmogsm SMC code more easy in the near future.
For the gsm340_gen_oa we are now using a small wrapper to generate the
proper type and numbering plan.