When losing the SCCP connection make sure that we free all
endpoints. The disconnection of the BSC should already make
sure they are closed but this makes sure everything is
properly reset.
For the nat we will have NAT and MGCP in the same process
and this commit starts with that. We are linking in the MGCP
code and one can embed MGCP config snippets...
* Return the SCCP connection. This will be needed to store the
assigned timeslot in there.
* Update code to work with this change
* This uncovered a bug in the CC handling, at the time the BSC was
passed it was still a null pointer and the code would have failed.
Moving it here means we can more easily test this code, there is one
behaviour change with the code that we only support paging messages
with one LAC and will silently ignore the others.
On a CC message we will need to remeber where the source local
reference of the network belonged so we can properly identify
the connection when receiving UDT messages.
Create a BSC<->MSC interface and use it for the BSC MSC IP and the
BSC NAT to reduce code duplication on handling reconnects to the MSC
and cleaning up the local state. The code is only partially tested
and will contain bugs. Currently both the BSC and the NAT will just
exit on connection loss and this way have the current behavior.
Based on the token the NAT/MUX is capable of figuring out
which LAC this BSC is supposed to satisfy. This will be
needed for messages like paging that can be done by LAC.
* Create struct bsc_nat and move the various lists into this structure
* Create the VTY code
* Call the VTY init and parsing code
* Create functions to create the types..
* Add some stuff into the bsc_connection to be used for the NAT with
proper config files. E.g. to close the connection if the BSC does not
respond to a given command.
Introduce a bsc_nat_parse method to parse a IP Access method
into various parts. Write out the IPA Proto, in case SCCP is used,
store the msg type, pointers to the source/dest local reference and
other information.
Use the result of bsc_nat_parse inside the bsc_nat_filter method
to decide if the message should be dropped or not.
In the future the bsc_nat_parse result will be used for patching
SCCP references and other parts of the message.
The filter language should be able to filter the msg type of SCCP
messages and gain the "NOT" word in the filter language.
The first part is to analyze the IP Access Header and only forward
SCCP messages for now. In the future we might want to do MGCP
signalling through this protocol and connection as well and need to
update this then.
* gsm_04_08_utils.c will directly send the message...
* gsm_04_08.c will use the DTAP API, add a new method to pull
in the data from the transaction...
When submitting a DTAP message, the BSC API will attempt to
establish the RLL layer and then send the message or send an
SAPI n REJECT. This will be used by the SMS code.
This will take care of the auth/check/enable cipher sequence
and call a callback function when done.
Currently the negotiated Kc is saved but not re-used, so
there is an authentication each time ...
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Ultimately, we'll need to store both the last used tuple by a
subscriber and a list of known tuples (for unknown Ki). What's
currently implemented for AuthTuples is the former behavior, so
reflect that.
The second use case will be added as a separate table with separate
accessors later on.
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
According to the GPRS NS spec the maximum framesize
is 1600 octets for FrameRelay, it can be bigger if
configured to be so. Make it 2048 octets to have some
space available...
We now have a function that generates BSSGP PS and CS paging request.
It is called from the libgtp code when we receive a GTP packet from
the GGSN for a MM context that is in SUSPEND state. We then issue
a PS paging request to the Cell with the BVCI where the last RA update
was being performed.
TODO: We still don't enqueue the GTP packet (and transmit it on paging
complete), and we don't rate-limit the paging requests, i.e. every GTP packet
will trigger another paging request.
We probably also need some kind of logic that marks the phone as UNREGISTERED
if it doesn't respond to paging requests for some time.
Using the code of this commit, it was possible to provision GPRS
services and access a website from a G1 phone (Qualcomm MSM7k baseband chipset)
using a nanoBTS, Osmo-SGSN and OpenGGSN.
There is still no fragment re-assembly in the uplink path yet,
despite the (untested) code present in the gprs_sndcp.c file
This only works for packets that are small enough to not need
fragmentation at the SNDCP layer (dns queries, ntp and the like).
It requires libgtp built from OpenGGSN dc3744fda045f9fca83de6881176987335a309a8
or later. Plain 0.90 will NOT work.
Using this version, I could see bi-directional traffic from various
phones going all the way through BTS, OsmoSGSN, OpenGGSN and being routed
to and from the real internet. Time to celebrate...
Holger Hans Peter Freyther
Sylvain Munaut
Harald Welte