Commit Graph

11 Commits

Author SHA1 Message Date
Neels Hofmeyr c8f37cb4d6 mgcp_client: add transaction cleanup
So far, if an MGCP message is sent, the transaction gets enqueued, but there is
no way to end the transaction other than receiving a valid reply. So, if the
caller decides that the transaction timed out and tears down the priv pointer
passed to mgcp_client_tx, and if then a late reply arrives, the callback will
dereference the invalid priv pointer and cause a segfault. Hence it is possible
to crash an mgcp_client program by sending a late response.

Furthermore, if no reply ever arrives, we would keep the pending response in
the list forever, amounting to a "memory leak".

Add mgcp_client_cancel() to discard a pending transaction. The caller can now
decide to discard a pending response when it sees fit (e.g. the caller's
timeout expired). This needs to be added to OsmoMSC and OsmoBSC.

Add mgcp_msg_trans_id() to provide an obvious way to obtain the transaction id
from a generated MGCP message.

No public API is broken; but refine the negative return code from
mgcp_client_rx(): return -ENOENT if no such transaction ID is found, and still
-1 if decoding failed. This is mainly for mgcp_client_test.

Implement a test for mgcp_client_cancel() in mgcp_client_test.c.

Tweak internal mgcp_client_response_pending_get() to take only the transaction
id as argument instead of the entire mgcp message struct.

Found-by: dexter
Related: OS#2695 OS#2696
Change-Id: I16811e168a46a82a05943252a737b3434143f4bd
2017-12-03 22:47:01 +00:00
Neels Hofmeyr c0dcc3c60c Revert "mgcp_client: don't configure "bts base"" until osmo-msc is ready
OsmoMSC is in the odd situation that it is already using the new 
libosmo-mgcp-client, which is targeted at osmo-mgw, to configure talking to the
old osmo-bsc_mgcp. By removing the bts_base, we break current OsmoMSC.

Removing bts_base makes sense, but let's revert this until OsmoMSC is ready
after merging Ieea9630358b3963261fa1993cf1f3b563ff23538 (which moves the 
osmo-msc over to osmo-mgw).

This reverts commit 0be3ce66c0.

Change-Id: Ibce214c2bfc35623097abbb647619426ef3dcc94
2017-12-02 18:37:18 +00:00
Philipp Maier f8bfbe8b14 client: use osmo_strlcpy instead of strncpy
simplify \nul termination of the ip_addr string

Change-Id: I94e3815f45d08e0d40faf41e580547de937c4ce8
2017-12-01 11:58:24 +00:00
Philipp Maier ffd75e420c libosmo-mgcp: Connection Identifiers are allocated by MGW, not CA
The MGCP connection identifier is allocated by the MGW while processing
the CRCX, see RFC3435 2.1.3.2:. Including/Accepting a connection
identifier in CRCX is "forbidden" as per RFC3435 Section 3.2.2.

So the MGW side must *reject* a CRCX message with 'I' parameter, and
allocate a connection identifier which is subsequently returned in the
response.

Closes: OS#2648
Change-Id: Iab6a6038e7610c62f34e642cd49c93d11151252c
2017-12-01 11:58:24 +00:00
Philipp Maier 01d24a3281 MGCP: Connection Identifiers are hex strings
The MGCP spec in RFC3435 is quite clear: Connection Identifiers are
hexadecimal strings of up to 32 characters. We should not print and
parse them as integers on either client or server.

Change the internal uint32_t representation of connection identifiers
to a string representation in the client and also in the server.

Closes: OS#2649
Change-Id: I0531a1b670d00cec50078423a2868207135b2436
2017-12-01 11:58:23 +00:00
Neels Hofmeyr 0be3ce66c0 mgcp_client: don't configure "bts base"
There should not be any BTS base port to be configured at an MGCP client.

Possibly this is related to the legacy behavior of libosmo-legacy-mgcp, and
certainly has no place in libosmo-mgcp-client.

Further changes may be needed to follow up on removal of the BTS base port
concept, at least drop it from the VTY for now.

Change-Id: I36e46208d7b75611e5ade3c74d8e1c25870de511
2017-11-30 12:18:57 +01:00
Harald Welte 9bf7c53779 cosmetic: fix whitespaces; we use tabs for indentation
Change-Id: I547f650bcda369ea399c5171a3541a96862d978b
2017-11-17 14:18:24 +01:00
Philipp Maier 06da85ed3a client: add ip address parsing to the client
Some MGCP messages (CRCX, MDCX) return IP-Addresses. Make use of
this information.

Change-Id: I44b338b09de45e1675cedf9737fa72dde72e979a
2017-11-02 11:47:44 +01:00
Philipp Maier 1dc6be6a82 client: add unified function to generate MGCP messages
currently the only way to generate MGCP messages is to use
mgcp_msg_crcx(), mgcp_msg_mdcx() and mgcp_msg_dlcx(). All
three function take a fixed set of parameters via their
parameter list. There is no way to add or leave away optional
parameters.

add function mgcp_msg_gen(), this function takes a unified
message struct. The struct features a presence bitmask which
allows to enable and disable parameters as needed. It is also
possible to add new parameters in the future without breaking
the API.

Depends: libosmocore I15e1af68616309555d0ed9ac5da027c9833d42e3

Change-Id: I29c5e2fb972896faeb771ba040f015592487fcbe
2017-11-02 11:47:44 +01:00
Neels Hofmeyr d95ab1e9ad libosmo-mgcp-client: fix debian, make self-contained
Add mgcp_common.h to libosmo-mgcp-client, to not need to share a header file
with libosmo-legacy-mgcp (nor the upcoming libosmo-mgcp). Both libraries use
the enum mgcp_connection_mode (and a for-loop macro and a string mangling
function), so far declared in mgcp.h, and both mgcp-dev and mgcp-client-dev
debian packages would require this header file to be installed. So far the
mgcp-client-dev lacks this header file, which causes the osmo-msc debian
package to fail building. Ways to solve:
- If both -dev debian packages installed the same header file in the same
  place, they would conflict if ever installed at the same time.
- mgcp-client-dev can depend on mgcp-dev, but it seems bad to keep such a large
  dependency for just one enum and two helpers.
- Instead, this patch solves this by copying the few definitions to
  libosmo-mgcp-client.

Once libosmo-mgcp-client has its own copy of those definitions, it is
fully self-contained and depending builds (osmo-msc deb) will succeed.

Copy the few actually common definitions to new header
<osmocom/mgcp_client/mgcp_common.h>. The nature of this .h is that it may be
shared with future libosmo-mgcp without causing linking problems.

Remove libosmo-legacy-mgcp/mgcp_common.c file from the build of
libosmo-mgcp-client, no longer needed.

Add to new mgcp_common.h:
- enum mgcp_connection_mode;
- for_each_non_empty_line() macro.
- mgcp_msg_terminate_nul() as static function.  Its complexity is just above
  your average static inline, but being inline is a way to use it in both mgcp
  and mgcp_client without linking problems.

Replace for_each_line() use in mgcp_client with for_each_non_empty_line()
(for_each_non_empty_line() replaces for_each_line() and uses strtok_r() instead
of a local reinvention).

mgcp_connection_mode_strs are actually only used in libosmo-mgcp-client, so
rename to mgcp_client_ prefix and move to mgcp_client.c.

BTW, the future plan for upcoming libosmo-mgcp is to use the identical header
file, and keep only one copy in the git source tree. The second copy may be
generated during 'make', to avoid code dup while having two distinct headers.

Related: I8e3359bedf973077c0a038aa04f5371a00c48fa0 (fix osmo-msc after this),
         I7a5d3b9a2eb90be7e34b95efa529429f2e6c3ed8 (mgcp_common.h)
Change-Id: Ifb8f3fc2b399662a9dbba174e942352a1a21df3f
2017-09-24 19:48:37 +02:00
Neels Hofmeyr 3a8e723a0d rename mgcpgw_client_* to mgcp_client_*
The name "mgcpgw_client" referred to an MGCP gateway, which is rather an MGW
(Media Gateway). But this client code is more generally a client for the MGCP
protocol, independently from what the server program is called.

Rename the files as well as the function prefixes to drop the "gw". It is
purely cosmetic and not strictly necessary, but a good point in time for fixes
like this.

osmo-msc build will be adjusted by I093ad02ca0e532f659447c785e09678b3e6f220d.
osmo-bsc build will be adjusted by I6402c7cbe58dacae7630f7f03819f8102e54c699.
These should be applied right after this here is merged to avoid fallout.

Change-Id: I99f7faab637cfcc22ece64a1dbcbe590f2042187
2017-09-08 23:37:46 +00:00