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..
When allowing to reallocate an allocated endpoint we will need
to free it first. When freeing we will free the call id and other
ids that we would have leaked otherwise.
For some mode of operation it can be acceptable to reallocate
an already allocated endpoint. This can be the case when we
only deal with one call agent that is keeping track of the
endpoint but slightly confused.
The are three policies. Accept, Reject and Defer. This will
allow to handle network connections and such from the policy
callback instead of directly acting on it.
In case of a wrongly formatted AUEP, CRCX, DLCX, MDCX the
transaction id pointer was a dangling pointer... Initialize
the transaction id to a static string..
Also fix a off by one bug. We want to extract four elements
from the MGCP message and not only 3... So a short AUEP message
made it us read too many things.
This change separates the protocol from the actual network code
(bind, forward data). This will allow to more easily hook up the
RTP code from OpenBSC and to not use local sockets at all.
The send_ methods stopped to send the MGCP messages but was
changed to actually just create a msgb_ that can be sent to
a mediagateway. Rename the methods now.
In separation of using the MGCP parsing in another context, refactor
the code to operate on a struct mgcp_config, split out the vty code
from the mgcp_protocol.c, and move the callbacks into the mgcp code.
There should be no functional changes.
This library is intended to collect all generic/common funcitionality
of all Osmocom.org projects, including OpenBSC but also OsmocomBB
The library currently includes the following modules:
bitvec, comp128, gsm_utils, msgb, select, signal, statistics, talloc, timer,
tlv_parse, linuxlist
msgb allocation error debugging had to be temporarily disabled as it depends on
'debug.c' functionality which at the moment remains in OpenBSC
Do not directly send data from inside the mgcp_protocol.c
implementation. Instead allocate and return a struct msgb*. The
caller can then either wrap that into the IPA protcol or directly
send it over the UDP socket.
* Call a callback when the endpoint was created, modified or deleted. This
can be used by the BSC MUX to send a MGCP packet over TCP to the right
the BSC to allocate the endpoint there with the right data, or it can be
used in the BSC to send the right commands to the BTS.
* Separate main process and protocol handling into two parts.
* Change the protocol handling to work with UDP and TCP connection
* This will allow to speak MGCP over TCP between the BSC MUX and
the real BSC.
Holger Hans Peter Freyther