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.
Inside the access-list we have a list of entries that have
either one allow or one deny rule... we do not allow to remove
a single rule but one has to remove the whole list, in that case
talloc will handle cleaning all entries.
Right now the matching is O(n*m) as we traverse the list
(multiple times) and run the regexp multiple times. One
way to make it faster would be to concat all regexps into
one.
One can set one access-list to one BSC and one
access-list to one NAT. The matching of IMSIs
remains the same for now, also applying the
white/blacklist. Access lists can not be deleted
for now and no perf opt is done (e.g. one could
cache the result of the last lookup in the bsc
struct).
We will need to confirm the connection, then we can send the
GSM48 message, then we need to close the connection... the
embedding in the refusal method was way too easy..
Right now it was not possible to just find a connection, by returning
the connection that is created we will have direct access to it. It
will be used by the local connection handling.
A local connection is only between the MUX and the real BSC. We will
not forward anything to the MSC. This will be needed for the IMSI
filtering as sending a CREF is not liked by every BSC...
For now we have:
1.) bsc imsi deny to deny at the BSC level
2.) bsc imsi allow to allow a SIM at the BSC level
3.) nat imsi deny to deny at the global level
We will send a ping every 20 seconds and if we have no pong
within 5 seconds we will close down the BSC connection and
wait for a reconnect. We will start this after having
authenticated the BSC and we stop the timer when destructing
the BSC connection.
Remember that we have seen a CC and have a valid destination
local reference now and only send a fake RLC to the MSC when
we had connections in this state.
When setting a new MSC timeslot to a SCCP connection check if
any of the existing connections have this timeslot, if so we will
send a DLCX down the stream to make sure it is closed there, when
we will CRCX this new timeslot we will happily reallocate it.
When the SCCP connection goes away, or we get a DLCX from the
network, or the BSC is gone we will send a DLCX message down the
stream as well.
When we receive a CRCX from the network we will forward the CRCX
as usual and send a dummy MDCX after it.
For the DLCX and the dummy MDCX we send a custom MGCP message
that will not provoke an answer. Even if the downstream MGCP GW
will answer we will ignore it due the dummy transaction id that
is not used anywhere else.
This change should make sure that we close the dowstream endpoint
all the time, even when the DLCX arrives after the SCCP connection
is torndown.
When sending a MSG to the MSC try to find the to be used "src" reference
by comparing the reference on the BSC and the BSC connection. Only this
tuple needs to be unique.
Actually only when looking at the SRC REF we need to compare the BSC as the
dest reference should be unique but we are just making the check a bit stronger
to make it look symmetric.
We will reset the multiplex in a DLCX message and then
we can reset the multiplex as well...even if the MGCP
connection is staying open. or at least this is a theory.
The MSC likes to leave a connection open during CallControl
when hanging up early enough in the process.
Count number of SCCP connections, number of BSC reconnects,
number of calls. For most of them we have a per BSC and a
global count.
Right now all structs using the counters survive until the
end of the application so we do not need to free them.
This method currently prepends the IPA header and sends
the data. In the future we might be able to use SCTP for
it.
We have to remove the IPA header from the static messages
for that to work.
This code is untested.
Remove the code to parse port as we need to discover the
BTS behind the nat and most likely it will have a different
port than the one advertised by the BTS.
This reverts commit c6a1fe773d.
Holger Hans Peter Freyther