The transaction layer was stopping paging requests that might or
might not have been owned by the transaction. This makes the subscr
code get stuck delivering requests. This code is mostly a band aid
and just makes sure that we will kick the queue if it is needed.
Remember if this channel got opened due a paging response and in
that case when we close it down we will call subscr_put_channel
that will try to page the subscriber again. This highlights the
lack of a good subscriber management in the MSC code.
The active channel might or might not be gone when the transaction
has been released. Instead of passing an invalid subscriber conn
we will pass the subscr that is ref-counted and guranteed to be
valid at this point. subscr_put_channel could search the connections
for an active connection if that is ever needed.
When the new_lchan for handover is failing we should stop the
handover operation. This is fixing a crash that we get a timeout
on the lchan and have no conn set to it. Introduce a flag to
the bsc_clear_handover to not free the lchan. In case the ho_lchan
is failing we do not want to call lchan_release as it would
reset the state.
Instead of creating the sockets in the RSL code we will do this
in the CRCX_ACK, MDCX_ACK, DLCX_IND signal handler of gsm_04_08.
Introduce a handover signal so we can repatch the RTP sockets in
the gsm_04_08 as well.
This adds mncc_sock_from_cc() as a handler function for CC messages
to be passed to the MNCC interface. If there is no MNCC socket
registered, we immediately release any CC related messages.
Together with flushing all established CC transaction at MNCC socket
close time, this ensures that all resources are released and no
new resources can be established until the MNCC applicaiton has
re-attached.
The MNCC messages now again get directly handled by the net->mncc_recv()
callback. If the callee wants to put them in a queue, it' his business
to do that.
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.
The SS_LCHAN signals now always include the lchan_sig_data. For
the measurement report it will optionally include the measurement
report as well. Attempt to update all handlers of this signal as well
The sms queue will attempt to send one SMS per subscriber
to fill all the available slots. It will handle the case
where paging has not started, timed out or if there was
any kind of other failure. It is also retransmitting SMS
in case of failures.
The SMSqueue will be responsible of sending to the user. It will
do so in a loop and will also try not to overload the BTS. This
means the throughput of SMS will be limited.
This is providing access to the paging result, the sms,
the transaction. This will allow the SMS queue to do
decisions based on the source of the failure.
Start counting the attempts of each paging request and call
the callback with the PAGING_BUSY type when the paging request
timed out but the subscriber was not paged at all. This can
only happen with a huge paging backlog.
In case the system has so many pending paging
Introduce a method that will remove all subscribers that have a
zero use count. This is useful if someone wants to purge subscribers
from memory or wants to disable the everything in RAM feature.
This is implemented by not freeing the subscriber when the
reference count becomes smaller than zero. We hope that this
will save many database accesses during the congres.
In the GPRS NS protocol stack, the amount of NS/BSSGP headers like MS RADIO
CAPA INFO can be quite long. In order to fit the full user message and
those headers, we have to enlarge the head/tailroom of the msgb allocations.
Currently the nanoBTS bootstrap code requires a high delay
otherwise we are not bringing the device up properly. Changing
the init code turns out harder than it seems like. So this is
a workaround for that to allow a high speed RSL/OML connection
after the bringup.
The line driver can have a default TS delay. It is set to the
current default for the nanoBTS and the BS11. For the ipaccess
case we will set the delay lower for the RSL connection and
inside the ipaccess-config we can set it low right away to
have fast firmware flashing and such.
Instead of sending many messages we will queue the OML
messages and wait for the ACK/NACK before sending the
next message from the queue. We tag the msgb to remember
if we need to wait for an ack or not.
We keep the order of all messages, on ACKs and similiar
occassions we will drown the queue until we reach a message
that needs to be acked and then wait for that ack again.
Possible breakage can appear when we send an OML (e.g.
BS11 specific message) msg which does not need to be acked
through the abis_nm_sendmsg call. The fix will be to use
the _direct version of this method.
Re-Enable as it might have fixed something... who knows.
Conflicts:
openbsc/include/openbsc/abis_nm.h
openbsc/include/openbsc/gsm_data.h
openbsc/src/abis_nm.c
openbsc/src/gsm_data.c
The default values are those where the parameters are encoded
as '0' and they're not output in the config file if that case
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Sending this as the RTP_PAYLOAD2 will produce a MDCX NACK
as we send the RTP_PAYLOAD in the CRCX. It does not seem to
be necessary to send anything != 0 for the RTP_PAYLOAD2.
Refactor the closing code of the CC timeout to a new function,
also make sure that the SCCP Connection is forced closed before
we destruct the connection for real.
This will change the LAI of a LU accept message to the LAI
used for the on-air network. It will also detect when to
send a welcome ussd to the subscriber.
For SAPI=3 on a TCH it might be nice to use the SACH to submit
the message. The api allows to automatically use the SACH if
a message like this is submitted.
The cipher mode reject will be send in case the BSC is not
able to support the requested cipher. So this reject can be
handled by however attempts to enable ciphering.
The implementation of bsc_hack would call subscr_con_free before
the BSC API has had the chance to call gsm0808_clear to try to
release other channels. Fix that by adding a return value.
This is used by the paging code of the osmo_bsc. When we get
a paging response there should be an active subscriber with
the TMSI or IMSI and we can stop paging. There is no need to
allocate a new subscriber.
In case of a inflexible network it is better to hardcode
the rtp payload to a given type. E.g. when using AMR5.9 on
a TCH/F and TCH/H having the same payload is helpful. For
now this will be only used by the osmo-bsc.
Send a RLSD down to the BSC in case the USSD Provider is gone. It
is not sending a Clear Command and ut depends if the BS+ will
like this kind of behavior. At least the data on the NAT will
be freed soon afterwards due the RLC message.
Extract the IMSI from the first message as well and safe it
in the connection structure. The problem is that we do not
have this structure at this point, so we will allocate the
imsi as child of the bsc_connection and then move/steal it.
Rename NAT_IPAC_PROTO_MGCP to IPAC_PROTO_MGCP and place it in
the enum. We need to be prepared to change this number if IPA
is ever going to use it for something else.
Remove a lot of code in favor of a new function that is freeing
the old string and copying the new one. I should have gotten the
context and the strings right.
Make it possible that one BSC is serving multiple
cells. Introduce a list of lacs, add functions to
manipulate the lists. The current test cases for
paging by lac continue to work.
The transcoder RESET is using the same extensions to reset all
endpoints on a remote site. This makes sure that all allocations
can be made in a properly configured network.
Bind a new port for the transcoder, forward data from the BTS
to the transcoder, and from the transcoder to the network. Leave
BTS-IN where it is, BTS-OUT can now be after the transcoding took
place. We send the data from the BTS RTP port.
This whole route will be guarded by the transcoder_ip and if it is
NULL (current default) it will not go through the transcoder.
The timeslot one is blocked and should not be used, replace the
code with a warning and watch out for it. Tis is most likely due
the uncovered in the previous commit due the wrong TLV definition.
Add the code that is forwarding data, from and to the MSC, also
handling ping/pong timers and authentication. Hook it into the
osmo_bsc. The code is only compile tested and ported from the
on-waves/bsc-master branch.
The grace code will decide if a given connection is allowed to
be made or if it is going to be rejected. For active connections
it is going to send a USSD message.
Keep a back pointer to the rf struct inside the connection,
resolve the network through the back pointer. Also assume
that the RF is on. In case we start with RF locked, the policy
is on but we will not see any MS talking to us.
Return early in case the IMSI was already checked, if not we need
to look at the connection and check if the message could contain a
imsi we want/need to filter.
Return -1 if the IMSI should be filtered, 0 if the IMSI could not
be checked and 1 if the IMSI was checked and allowed to pass. In
the future this will be used to inspect every message coming by.
Only page if we have a load that is acceptable for paging. This
option is off by default, and can be enabled per bts. The idea
is that when we have no resources right now we will not page as
it will only create more RACHs and increase the load.
By default we are keeping the old behavior to always page and
only by changing a setting one is using the new behavior.
It might be that we run down to zero available slots but the BTS
might not send us a load indication. This can happen if we think
we send paging requests and the BTS disagrees and considers them
as errors and does not count the paging message.
When we drop to zero we will start a credit timer to give us extra
credit after six seconds, if we get a CCCH load indication before
we will stop the timer.
It is possible that the MSC is not sending the channel type it
needs for the operations it wants to do. Add a configuration option
to assign a TCH in case of paging any requests. It can be a good
idea to leave SDCCHs free for location updating requests and use
the TCH for SMS-MT and CC-MT.
Store the mapping from request to channel type in the GSM Network
struct as there is some policy involved with handling the request.
E.g. in a half rate network we don't want emergy calls to be getting
a TCH/F, or we want to have a different policy for early/late assignment
of phone calls. Update the table when creating the network and when
the neci is changed.
Allow the MS to use uplink discontinous transmission by
setting the right bit in the SystemInformation and set
DTXd/DTXu on the RSL channel commands.
This is configurable via dtx-used (0|1) on the network
level and still considered as experimental.
When the cell becomes visible we will be bombed with location
updating requests and to reduce the load on the network we should
assign as many channels for it as possible. During load peek it
is even more important than to have a spare voice channel and in
general the LU procedure is pretty fast.
Assume that if the MSC has assigned a timeslot/multiplex it will
also be used for the MGCP. So we just assume that it was allocated
on the BSC as well... in the worse case we will send a DLCX downstream
but it should be fine.
We are going to have more than one trunk, so all code hardcoding the
multiplex to zero must go. Avoid this kind of problem by saving the
MGCP endpoint number and comparing that.
Do not use the CI_UNUSED to decide if an endpoint is allocated
but introduce a new flag. This way only the CRCX and free_endp
play with the allocated field.
For debugging it is useful to forward (tee) UDP packets to another
system and use gstreamer to inspect the rtp stream. This is untested
code and might contain bugs.... and of course only tap your own calls.
Allow to switch to a dynamic port allocator and not reuse
the ports for a long time... This should help with a crazy
network sending two streams at the same time.
We plan to have two different ports for the network and for the
BTS to avoid detecting the BTS and to dynamically allocate the
port to have old data not go to a new socket.
common_vty.c was including bsc_nat.h which tried to
get the sccp/sccp_types.h which is not required to be
installed. Move all structs using/embedding SCCP structures
into the bsc_nat_sccp.h and include. This should fix
the compilation.
Currently every SAPI release indication will trigger the channel. It
was possible that we had SAPI=3 and SAPI=0 allocated and we tried to
release the channel by sending a RF Channel Release, the BTS answered
with a RF Channel Release ACK but also sent the SAPI Release Indication
which triggered a channel release here. So it was possible that we
would have released a newly allocated channel because of the SAPI
release of the old connection.
This code now works by releasing all SAPIs from highest to lowest,
then sending a SACH Deactivate and finally releasing the channel. This
approach is in use on the on-waves/bsc-master.
Add --enable-nat and --enable-osmo-bsc to build applications
requiring the Osmo SCCP library to be installed. We are not
using autodiscover as this is out of fashion.
This code compares the UDP sequence numbers of two RTP messages
and guesses if packets are missing. It is guessing in two ways:
1.) by default the sequence number is 0, so on the first
value we ignore the jump... we might ignore a real issue
in case of a wrap around which is easily possible as the
sequence should be a random number.
2.) the UDP stream might have been reordered on the network
and we would see the jump...
In any case these two shortcomings are acceptable for the feature
that is meant to provide some basic analysis..
We need to release the USSD unit, otherwise it is staying blocked
and will stop to function (even across LUs on my a1200). This code
should encode the transaction and the direction depending on the
network state but this is omitted right now.
... while asking the BTS to perform tests for us. The length of the
ARFCN whitelist is the actual length in bytes, not the number of 16bit
ARFCN numbers.
Also, implement a limit, either by rxlevel or by number of ARFCN
that should end up in the whitelist.
Also, we now re-start the network listen test after it has finished,
so if you run a test from ipaccess-find, the test will get re-started
and re-started all the time.
* We should create the transaction for SMS, CC on the CM Service Request
but for now we will use a band aid and create a dummy operarion to wait
five seconds for the transaction to be opened.
sgsn_rx_sndcp_ud_ind() can no longer make the assumption that msgb_bcid() is
valid, as this is only true for an un-fragmented SN-PDU. So instead,
we now store the RAID in the SNDCP Entity and pass it as an explicit
argument to sgsn_rx_sndcp_ud_ind().
The transaction should not know on which lchan we are operating
as this can change due handover. Add untested code to share the
subscriber connection of the new and old lchan and move the pointer
in case of success/failure. Also on a clear command we will free
any resources allocated...
This code is not tested and needs to be debugged, but it should
have the right structure. I am going to fix a potential memleak
in the next commit.
A channel will be released in case of
* Errors via the clear_request callback...
* no more transactions and operations are going on.
This means that if we do something without a transaction
the channel might be closed down right away. The bug fix
will be to create a transaction/operation.
This is a big change to the way we use the subscriber
connection. From now on it is is dynamically allocated
and we will slowly move from a 1:1 lchan to conn to
having more than one lchan per connection.
This is the first commit, the subscr_con* methods will
move to gsm_data once the use_count is removed from the
connection, the freeing of the connection will also change.
The Channel Activate might be sent to a different TRX than the
Immediate Assignment. So we need to make sure that the channel
is activated before we send the immediate assignment for the RACH.
Another reason for that is according to GSM 08.58 we should take
the frame number from the activate and use it for the starting
time inside the immediate assignment message. We obviously do not
do this yet.
The code assumes that the BTS will either respond with a CHAN ACK
or a CHAN NACK if not the lchan will remain in the request state.
Also, make sure the bit ordering in the pre-computed MA is correct,
as well as the cell channel description of the target cell being
present in the HO CMD.
We now compute the Cell Channel Description for SI 1 by bit-wise
OR of the ARFCN bitmask of each timeslot on all the TRX of the BTS.
Also, support generating a GSM 04.08 Channel Description IE for
the hopping case (with HSN/MAIO instead of ARFCN).
What's still missing now: Sending the 04.08 Mobile Allocation IE
Holger Hans Peter Freyther
Harald Welte
Sylvain Munaut
Andreas Eversberg