Commit Graph

7 Commits

Author SHA1 Message Date
Pau Espin 3babd1a803 Make function amr_is_octet_aligned publicly available
it will be used by mgcp_iuup.c in follow-up patch.

Change-Id: Iffaf90c1f713feef0c609a7581a346f5f28141d9
2022-02-16 17:59:18 +01:00
Philipp Maier 993ea6be7a get rid of mgcp_internal.h
The file mgcp_internal.h still contains mostly definitions and types
that are relevant for mgcp_network.c and mgcp_protocol.c. Lets give
the network and protocol module its own header files, also move stuff
that does not relate to protocol and network to the appropiate places.

Change-Id: I837eaad771ed7252304db4a81c37953b70766fff
2020-08-10 22:56:59 +02:00
Neels Hofmeyr 51b42ff2e1 refactor: use msgb to receive, pass and send RTP packets
Instead of numerous arguments (buf, len and context data), use a msgb, like
most other osmo programs do, with a msb->cb pointing at a context data struct.

This opens the future for adding/stripping IuUP header data from the msgb
easily.

(Checked to pass current ttcn3-mgw-tests.)

Change-Id: I3af40b63bc49f8636d4e7ea2f8f83bb67f6619ee
2020-07-21 16:13:23 +00:00
Neels Hofmeyr 740af6ed44 mgcp_codec: constify 'param' arg
Change-Id: I3ec6b57298f78604d5cd453f1db6d90ddfd6a2ba
2019-08-09 02:28:37 +02:00
Philipp Maier 228e591589 AMR: Add function to convert between bw-effient and octet aligned mode
RFC3267 specifies two framing modes for AMR packets. An octet aligned
mode is specified where all fields of the AMR packets are aligned to
octet boundaries. The second framing mode is the bandwith efficient mode
where the fields are directly packed one after another.

- add paring/generation functions for related SDP fmtp parameters
- add conversion function to convert AMR payload

Depends: libosmo-netif I5b5a0fa644d8dbb1f04f9d7e35312683c7b3d196
Change-Id: I622c01874b25f5049d4f59eb8157e0ea3cbe16ba
Related: OS#3807
2019-03-12 09:56:28 +01:00
Philipp Maier 6931f9a7a4 mgcp_network: translate payload type numbers in RTP packets
Since no transcoding is in place osmo-mgw forwards the incoming rtp
packets as they are (there may be minor modifications of the header) from
an ingress connection to an egress connection.

This works without problems as long as both connections use the same
payload type. For IANA defined fixed payload type numbers this is
usually the case, but for dynemic payload type numbers both ends may set
up the same codecs but with different payload type numbers.

When different payload type numbers are set up, and the packet is passed
through without modification, it will have the wrong payload type when
it is sent. The receiving end may then toss the packet since it expects
packets with the payload type it has configured.

The machanism, which is introduced with this patch looks up actual codec
inside the struct data of the ingress connection and then looks for the
matching codec in the struct data of the egress connection. When it
finds the codec there it looks up the payload type of this codec. The
header of the RTP packet is then patched with the correct payoad type.

- Add function mgcp_codec_pt_translate() to look up the payload type
- Add unit-test for function mgcp_codec_pt_translate()
- Add payload type translation to mgcp_network.c

Change-Id: I3a874e59fa07bcc2a67c376cafa197360036f539
Related: OS#2728
Related: OS#3384
2018-07-31 17:18:14 +00:00
Philipp Maier bc0346e080 mgw: clean up codec negotiation (sdp)
The codec negotiation via SDP is currently in a neglected state. Also
osmo-mgw does some kind of codec decision wile the SDP is parsed, the
result is information for one codec, even when there are multiple codecs
negotiated. This is problematic because we loose all information about
alternate codecs while we parse. This should be untangled and the
information should be presevered. Also we are not really capable
picking a default. Wehen we do not supply any codec information (not
even LCO), then we should pick a sane default codec.

- separate the codec decision from the sdp parser and concentrate
  codec related code in a separate c file
- add support for multiple codecs in one SDP negotiation
- do not initalize "magic" codec defaults during conn allocation
- do not allow invalid payload types, especially not 255. When
  someone tries to select an invalid payload type, do not fail
  hard, just pick a sane default.
- handle the codec decision in protocol.c, pick a sane default
  codec when no (valid) codec has been negotiated (no LCO, no SDP)

Change-Id: If730d022ba6bdb217ad4e20b3fbbd1114dbb4b8f
Closes: OS#2658
Related: OS#3114
Related: OS#2728
2018-06-23 11:39:44 +00:00