So far we allow only MGCP_MAX_CODECS-1 entries, because the parsing exit
condition hits only after the array size check. Instead, check the array
size a bit later, just before actually adding a valid entry.
This is verified to work as expected in upcoming patch
I842ce65a9a70f313570857b7df53727cc572b9e6 that adds a new
mgcp_client_test.c section for this.
Change-Id: I9a28da85e437f118026ea71a5a708e5758fff623
codecs[] is an array of enum osmo_mgcp_codecs.
ptmap[] is an array of { enum osmo_mgcp_codecs, unsigned int ptmap }.
MGCP lists first a bunch of payload type numbers and then specifies them
again for details, like the numbers 112, 96, 3 in this example:
m=audio <port> RTP/AVP 112 96 3
a=rtpmap:112 AMR/8000
a=rtpmap:96 VND.3GPP.IUFP/16000
a=rtpmap:3 GSM-FR/8000
So far we keep these lists in two separate arrays:
- codecs[], codecs_len stores the 'm=audio' list
- ptmap[], ptmap_len stores the 'a=rtpmap' list (and may omit some
elements present in codecs[])
This applies to both struct mgcp_response and struct mgcp_msg.
These are semantically identical, and the separation leads to checks,
conversions and dear hopes of correct ordering.
So let's keep only one list with both codec and payload type number in
it. The 'm=audio' list establishes the order of the pt numbers, and the
'a=rtpmap' list adds codec information to the established entries.
In the internal API structs mgcp_msg and mgcp_response, just drop the
codecs[] entirely.
In public API struct mgcp_conn_peer, keep the codecs[] array, mark it
deprecated, and provide a backwards compat conversion: if any caller
invokes mgcp_conn_create() or mgcp_conn_modify() with codecs[] still
present in the verb_info arg, then move codecs[] entries over to the
ptmap[] array in a sensible way.
(BTW, even mgcp_conn_create() and mgcp_conn_modify() are never called
from outside of libosmo-mgcp-client in any of our osmo-cni programs;
users call osmo_mgcpc_ep_ci_add() and osmo_mgcpc_ep_ci_request(), which
in turn may pass user-provided codecs[] lists on to mgcp_conn_create() or
mgcp_conn_modify().)
Tests for parsing the MGCP response are mostly missing. They will be
added in upcoming patch I842ce65a9a70f313570857b7df53727cc572b9e6,
because they will be using only the new ptmap API.
Related: OS#6171
Change-Id: I798e02c6663376d3d52f4a74fc4b32411ce95bed
As was pointed out during code review of a previously merged patch,
whenever we write something to the tailroom, we must use msgb_put().
Change-Id: Ibe1605631a94088bfd1f603f7043322ed5585ffe
We need to be able to terminate the received string in case it was
not nul-terminated by the sender (see mgcp_msg_terminate_nul()).
Change-Id: Icc878af7f671213bb516af62cb601914d86ff808
Fixes: CID#272990
The current statement:
msg->l2h + msgb_l2len(msg)
looks as follows, if we expand the msgb_l2len():
msg->l2h + msgb->tail - msg->l2h
so this is basically equal to msgb->tail alone.
Change-Id: I4f4b0f792bbeef94a5449c4a5843628a703a3d54
Related: CID#272990
There is an upcoming modification of structs mgcp_msg and mgcp_response.
When it is public API, it needs to be kept backwards compatible.
But no libosmo-mgcp-client caller (in the osmocom-cni world) has used
these structs in years and years. Everyone should use the higher level
osmo_mgcpc_* API only.
Move this legacy API to a private header, so we no longer need to worry
about compatibility there.
Related: OS#6171
Related: I798e02c6663376d3d52f4a74fc4b32411ce95bed
Change-Id: I6d8bdda5c2ffa236e94a0b6111de4dbfac923187
end.codec may be NULL, depending on whether a single matching codec
could be found or not, i.e. based on external input. So let's not crash
if an RTP packet arrives while end.codec == NULL.
Change-Id: I9bfb55a343b3f2b1459e0aba4ee71a6133b992b3
A client may know the IP address during CRCX but not yet the port, or it
may simply want to hint an initial IP address so that the MGW can better
guess when allocating a local IP address.
Related: SYS#6657
Change-Id: I30165dbac5e484011d0acf46af36f105954a501d
Do not refuse IuUP Initialization messages coming in on an RTP port if
the remote port is not yet known.
If an IUFP conn is not yet configured (pre-Initialization), allow rx
from any address or port.
An osmo-mgw client (eg. osmo-hnbgw) may wish to initially set a remote
IP address as a hint during CRCX, hence the IP address may already be
set while the port may be unset.
Related: SYS#6657
Change-Id: Idd833997abce46886e9664505b2776fa5dadc8db
We have proper IuUP support and everything about this legacy hack should
be purged.
The purpose of this function is to validate that RTP is coming from the
expected address and port. To allow that legacy IuUP hack, which is no
longer needed, we punched a hole into this validation, by adding this
special case for loopback mode (suddenly we don't care who or what sends
RTP and bounce it back to anyone). So let's get rid of this hole that
was only needed for very early 3G voice hacking.
Instead, we permit RTP for IuUP Initialization regardless of the RTP
loopback/send/recv mode since I6c365559a7bd197349f0ea99f7a13b56a4bb580b
Related: SYS#6657
Change-Id: I158dd046fdfcb10392cde3de8cc88dd095a05b40
Do not refuse IuUP Initialization messages coming in on an RTP port if
the remote IP address is not yet known.
If an IUFP conn is not yet configured (pre-Initialization), allow rx
from any remote address if the remote IP address is not yet known.
If we refuse the IuUP Initialization, a 3G RNC may fail to set up a RAB.
We will know the remote address only *after* assigning a RAB succeeded.
So the IuUP Initialization must be allowed before knowing all addresses.
At the time of writing, CRCX for IUFP are sent to osmo-mgw in either
LOOPBACK or in RECVONLY mode:
- current osmo-msc: recvonly
- osmo-msc <= v1.10.0: loopback
- osmo-hnbgw: loopback
IuUP Initialization should work regardless of that.
See also next patch I158dd046fdfcb10392cde3de8cc88dd095a05b40
IuUP is one layer below the loopback/send/recv decision for RTP; IuUP is
always terminated at the MGW, while the AMR payload carries through.
Related: alternative patch Idd833997abce46886e9664505b2776fa5dadc8db
Related: SYS#6657
Change-Id: I6c365559a7bd197349f0ea99f7a13b56a4bb580b
A typical OS imposed limit is 1024 open FD, which can bee too low when
there are hundreds of concurrent voice calls.
In systemd service file, set a super high limit of 65536.
In osmo-mgw's user manual, add section 'Configure limits' describing
this in detail.
Related: OS#6256
Related: osmo-bsc I26c4058484b11ff1d035a919bf88824c3af14e71
Change-Id: I46512517bc3b5bb90cac7643e7ac73afba398d36
A user reports crashes of osmo-bsc upon EV_MDCX. It turns out that there
is a lot of error reporting and a distinct possibility to get a NULL
return value because of external input. Terminate the FSM instead.
FSM termination is the proper way to report a bad error, it signals the
parent_term_evt to the FSM parent, which will then be able to act on the
failed MGCP operation.
Related: SYS#6632
Change-Id: Ia5d8a9aff565399a85a5b116d7029fedcab234e0
Before:
CONN: (1226/rtp, id:0xD94316AD, ip:127.0.0.2, rtp:2344 rtcp:2345)
After:
CONN: (1226/rtp C:D94316AD r=127.0.0.2:2344<->l=127.0.0.1:4002)
While changing that string, also include these changes for consistency
and readability:
- use the same r:...<->l:... format as osmo_sock_get_name().
- Instead of 'id:0x' use the actual MGCP format 'C: 9B686BE3'.
- drop the commas
- drop RTCP port: it is always RTP+1 and always an odd number.
Rationale:
The CONN pairs associated with each endpoint show remote RTP
ports. When osmo-mgw is being used by both BSC and MSC, one
side of the pair is showing the internal loop connection inside
osmo-mgw, while my intuition suggested this connection pair
is showing me the RTP port tuple of a single RTP stream. Adding
the local port to the display makes it more clear, IMHO.
Seeing the local port can also help to correlate the MGW vty
dump with a capture of RTP.
Implementation:
I first tried directly using osmo_sock_get_name_buf() on
conn->u.rtp.end.rtp.fd, but that might hide already known information
when the fd is not actively used yet (before SDP): the local address and
port would then be shown from the fd, not from
conn->u.rtp.end.local_addr/_port == hidden before the fd is set up.
Patch-By: whytek, nhofmeyr
Change-Id: Ib89a6779e1d68c6600f00699d4303f6c0ee07132
The mgcp client may first configure the connection to use RTP-AMR, but
after setting up another call leg may find out that both legs are IuUP
and hence want to forward the IuUP between the 2 connections instead.
In that case, an MDCX with codec VND.3GPP.IUFP would be set.
Until now, osmo-mgw didn't take that scenario into account, and it was
only upgrading the rtp conn to iuup internally during CRCX.
As a result, in the mentioned scenario osmo-mgw would continue to
output RTP instead of IuUP after the MDCX with VND.3GPP.IUFP, which is
wrong.
Related: SYS#6578
Change-Id: Ic94bf90f54d8ba3e65a2cd52734867847f3a60c2
For each RTP packet that is received from a connection, the mode is
checked whether receiving is allowed or not. If not it is discarded.
In case of "confecho" mode, the RTP is also sent by the receiving
connection.
Then a loop is used to send RTP to all sending endpoints except the one
that received the packet.
Because we have a loop that allows to have 1..n connections, we have no
maximum number of allowed connections anymore.
Change-Id: Ic99a55ab5a3a6170e940403fadd52697e99f2f3a
Related: OS#4853
The new mode "confecho" is similar to "sendrecv", except that it also
echoes back RTP towards the sender. This is required for voice group or
broadcast calls. Talker and listeners use the same timeslot, so that
audio must be echoed from the talker to the listeners.
It is different from "loopback", because a loopback only echoes back RTP
towards the sender, but does not forward audio through the endpoint to
the other connections. Also it does not forward RTP from senders of
other connections.
The current implementation of MGW does not support transcoding and
mixing. This means that a sending connection must not send RTP that has
been received by multiple receiving connections. The application that
uses the MGW has to set the connection modes, so that only one
connection receives RTP in case of a conference.
Change-Id: I0639c663e119d85bef1010c7aa45e2f133a9daf0
Related: OS#4853
Instead of calling strlen() for every loop iteration, just use strchr()
to find the position of '/'.
Change-Id: Ifc7302b6c5f9288a622e33c3e8b5fe0e7037dbdc
In the "L: a:" header, read the first codec name only up to the ";"
separator, and ignore the rest.
According to RFC-2705, the "L: a:" header may include multiple codecs
like "GSM-EFR;GSM" in:
L: p:20, a:GSM-EFR;GSM, nt:IN
osmo-mgw can handle only a single codec here. Since recently, osmo-msc
is our first client that may actually send more than one codec. This
uncovered a bug that leads to failing voice calls:
* osmo-mgw parses the entire list "GSM-EFR;GSM" as a single codec name,
* puts that into the ptmap without scrutiny,
* and even sends it back in the OK response, in the *SDP* part, as a
single "GSM-EFR;GSM" codec entry.
We do not care very much about the "a:" codec list, because we always
establish codecs via SDP later. So all we need to fix this is: parse the
first codec done correctly, and ignore the rest.
Related: OS#6081
Change-Id: I0342e85b32ed89f3a1fdb6131c3c8ded8f47a455
Abort with error log when map_str_to_codec is -1, instead of writing it
as unsigned integer into ptmap[i].codec.
Related: OS#6074
Change-Id: I08b91c849d810fe3cdb72c0f6f2a558b7377deab
This way if keepalive becomes disabled for an MGW, it can be selected
again (otherwise it would become non-selectable forever, and we already
have a "blocked" config for that).
Fixes: 563386e8bb
Related: SYS#6481
Change-Id: I263d23885a1a967f844033f9810b96691b8e3b30
In the previous logic, if "keepalive request-interval" was disabled
(value 0, default), then if the client was configured to send a DLCX on
startup it would end up in state UP or DOWN depending on whether the MGW
answered to that request.
As a result, an MGW that wouldn't answer would be left forever in DOWN
state since it would have been selected no more and there would be a
keepalive configured to re-mark it as UP.
Fixes: 563386e8bb
Related: SYS#6481
Change-Id: I290f7436f48418ee25179951359c76208796e279
This way the user ends up picking a working MGW instance instead of one
which is not reachable around the time.
Related: SYS#6481
Change-Id: Ia3f451d3cd97851f65074408812b1ddc68f67056
The `keepalive` feature in libosmo-mgcp-client allows scheduling periodical
queries on the MGCP layer in order to make sure it is reachable and hence
obtain information on the state of the MGCP link.
This patch only uses it to print the status on the VTY, but it will be used
too in a follow-up commit by the MGW Pool when picking an MGW from the pool:
MGWs whose link is considered to be DOWN are skipped.
The feature consists of:
- A `keepalive request-interval` which will trigger a transmission of an MGCP
AuditEndpoint command targeting endpoint with name `keepalive request-endpoint`.
This interval is updated every time any message is transmitted in the MGCP
link, meaning the MGCP AuditEndpoint message is only triggered if no message
has been transmitted since `keepalive request-interval` seconds ago.
- A `keepalive timeout` considering the MGW to be non-reachable (link DOWN) if
no message is received over that amount of time.
The `keepalive` parameters are to be preferrably configured so that
"keepalive request-interval" * 2 < "keepalive timeout".
Example VTY configuration of `keepalive` feature in libosmo-mgcp-client:
----
mgw 0
...
keepalive request-interval 20 <1>
keepalive request-endpoint null <2>
keepalive timeout 50 <3>
----
<1> Transmit an MGCP AuditEndpoint message to the MGW if no message has been
sent to it over last 10 seconds
<2> The MGCP AuditEndpoint targets the `null` endpoint. This is a special
endpoint available at OsmoMGW for those purposes, but any available
endpoint can be configured and used instead.
<3> Consider the MGCP link to be DOWN if no message is received from the
MGW over the last 50 seconds
NOTE: The `keepalive` feature is disabled by default, and must be explicitly
configured in order to enable it.
Related: SYS#6481
Change-Id: I3dc74c78548d017f272da863d5282dc5e0020ca3
This is a special endpoint which can always be audited. This is useful
for clients who wish to submit requests to osmo-mgw periodically to find
out whether the MGW is still reachable. This endpoint will be used by
libomso-mgcp-client as default target endpoint to implement such
feature.
This "null" Endpoint is osmo-mgw specific, not described in MGCP specs.
Related: SYS#6481
Change-Id: Ia409b16e9211e6261e2e0f21288544289d6f3733
This is a preparation commit for follow-up one, where some of these
functions need to be used in other static functions.
Related: SYS#6481
Change-Id: I3a00d8c47ec773390d9626364c4c75ca579f1508
So far, the users of the old non-pooled API were in charge of allocating
the struct mgcp_client_conf by themselves, then init them using
mgcp_client_conf_init(). This causes a major problem, since it makes it
difficult to extend the struct mgcp_client_conf structure to add new
features, which may happen frequently.
The MGW pool API doesn't have this problem, because the struct
mgcp_client_conf is allocated as parts/fields of private structs defined
in internal headers. Only pointers to it are used in public headers.
Since it still has to internally initialize the conf fields, we still
need the API to initialize it internally, and hence why is it marked as
DEPRECTED_OUTSIDE instead of DEPRECATED.
While some programs already moved to the new MGW pool infrastructure,
they still use the old APIs to accomodate for old config files in order
to be back-compatible, hence most users of libosmo-mgcp-client are
affected.
Introduce an API to allocate the conf struct internally, which, while
still breaking the ABI, allows for a more relaxed update path where it's
possible to extend the struct mgcp_client_conf at the end.
Eventually the non pooled API should be gone and the struct
mgcp_client_conf can then be moved to a private header, but for now
let's add this small feature to avoid major ABI breakage.
Change-Id: Iba0853ed099a32cf1dde78c17e1b34343db41cfc
Some payload type numbers are defined in 3GPP TS 48.103, let's put the
spec reference between all of those so that it is immediately clear
where those numbers come from.
Change-Id: Ie9d949ee72286ee4de7590c99acc740011208466
When two codecs are checked for convertibility we insist that
subtype_name and rate are equal since normally when those are different,
we assume a completely different codec that will require a transcoder,
which we do not have yet.
However when IuFP is used, the call agent will always negotiate IuFP as
VND.3GPP.IUFP with a rate of 16000, even though the IuFP payloads
contain regular AMR at a rate of 8000.
This means that if we detect IuFP on one side of the call leg and AMR on
the other side of the call leg, we must not insist on equal subtype_name
and rate.
This fixes the following TTCN3 testcases:
MGCP_Test.TC_two_crcx_mdcx_and_iuup_rtp
MGCP_Test.TC_two_crcx_mdcx_and_iuup_rtp_rfci_unordered
Related: OS#5461
Change-Id: I6bc1e6022efe21cb893ef213f3da35017960357d
When a call leg is set up, then the call agent (e.g. BSC, MSC, etc.)
will also negotiate a codec along with a payload type number. When
sending RTP packets, each RTP packet must also contain the negotiated
payload type number. To prevent the emission of RTP packets with an
incorrect payload type number, ensure that no packet is sent when
mgcp_patch_pt() fails.
Change-Id: I013a24c1e0f853557257368cfab9192d4611aafa
Related: OS#5461
Unfortunately OsmoMGW was never really tested with multiple different
codecs on either side of the connection. While OsmoMSC and OsmoBSC only
assign exactly one codec on each side this has never been a problem,
however it might become a problem when a call agent assigns multiple
codecs on one side. This has been observed in a setup where OsmoMGW had
one leg towards an external call agent. Also due to recent upgrades to
the TTCN3 tests we are now able to simulate different codecs on both
sides to pinpoint issues.
Testing has shown that OsmoMGW has difficulties with multiple codecs.
The reason for this is that the function that makes the codec decision
was not fully finished. So let's finish the codec decision function and
let's also use that decision when patching the payload type of outgoing
RTP packets.
Related: OS#5461
Change-Id: I6c3291f825488e5d8ce136aeb18450156794aeb5
In a follow up patch we intend to fix mgcp_codec_decide, since the
fixed version of mgcp_codec_decide will use some functions below its
current position let's move it down before fixing it to make reviewing
the changes easier.
Related: OS#5461
Change-Id: I2f2538ff912eae4d80d3b74b766e18c4da94d6b6
Neels Hofmeyr
Vadim Yanitskiy
Pau Espin
Andreas Eversberg
Keith Whyte
Oliver Smith
Philipp Maier