Add this new function to explicitly remove an existing circuit. Thus, the
client application (openbsc) is in full control to release circuits.
Before this patch, the circuit object was added when the first RTP messages was
seen, and it was removed when transforming the list of pending RTP messages to
the Osmux message (once the timer expired).
Moreover, check circuit->nmsgs to account bytes that are consumed by the osmux
header, given that !circuit doesn't mean "this is the first packet" anymore.
Add a new field to count the number of messages in the batch that are pending
to be transformed to osmux. Use this new field to check when to enable the
osmux timer.
The follow up patch keeps circuit objects in the batch until they are closed,
so we won't be able to rely on this to know when to enable the timer anymore.
I think this is a better name for this object. Basically, an input handle
represents a batch that is composed of one or more circuit objects.
Each circuit object contains a list of RTP messages that are pending to be
converted to the osmux format in one single batch.
This new structure serves as container of the internal osmux state during
transformation from RTP AMR to the compressed osmux format.
This reduces the footprint of several functions and it makes them easier to
extend if we need to pass new information between functions.
When libosmo-abis is installed in a distinct prefix, the build failed
with non-found headers, for example:
../../src/rs232.c:38:35: fatal error: osmocom/abis/e1_input.h: No such file or directory
#include <osmocom/abis/e1_input.h>
Use the new macros to deal with little/big endian. Im a bit
worried to make this change due the little test coverage in
this module but in case of a typo the elements would not be
defined.
Make sure we don't release a osmux handle with an armed batch timer.
==9753== Invalid read of size 4
==9753== at 0x4043CA2: rb_first (rbtree.c:293)
==9753== by 0x403E172: osmo_timers_check (timer.c:256)
==9753== by 0x403E69E: osmo_select_main (select.c:124)
==9753== by 0x804EBD3: main (bsc_nat.c:1613)
==9753== Address 0x4302670 is 56 bytes inside a block of size 108 free'd
==9753== at 0x4023B6A: free (vg_replace_malloc.c:366)
==9753== by 0x40494CF: talloc_free (talloc.c:609)
==9753== by 0x40AB279: osmux_xfrm_input_fini (osmux.c:620)
==9753== by 0x80651FC: osmux_disable_endpoint (mgcp_osmux.c:96)
==9753== by 0x805CAFF: mgcp_release_endp (mgcp_protocol.c:1540)
==9753== by 0x805DD35: handle_delete_con (mgcp_protocol.c:1274)
==9753== by 0x805E998: mgcp_handle_message (mgcp_protocol.c:415)
==9753== by 0x804CFF1: mgcp_do_read (bsc_mgcp_utils.c:972)
==9753== by 0x403F96D: osmo_wqueue_bfd_cb (write_queue.c:48)
==9753== by 0x403E724: osmo_select_main (select.c:158)
==9753== by 0x804EBD3: main (bsc_nat.c:1613)
If it is not possible to put the RTP message into the batch in case that:
1) The message is malformed.
2) The message is duplicated.
3) OOM.
4) The batch is already full.
Osmux releases the messages and gets back to the upper layer with an OK
to give another chance to follow up RTP messages.
This patch also fixes a use-after-free that was possible when the batch
was full. The message was released and osmux_batch_add() was returning 0
osmux_xfrm_input(), which resulted in accessing the released message
when updating the statistics.
This is ugly, with many ifdefs, but they don't want any debug message
that can be spamming. I don't want to remove these because there is
no dissector for osmux, and this can be useful for troubleshooting.
Should be enabled only in case you consider that Osmux should
is lagging when reconstructing RTP messages. I haven't seen
any issue regarding this so far. Let's disable it by default.
This patch adds a new field to the struct osmux_in_handle that allows
you to specify the osmux frame size. If not specified, the default
size assumes your nic uses a mtu of 1500 bytes.
Remove message that is printed twice and reword the messages to
make it more clear the traffic flow when compressing and
decompressing the RTP AMR traffic.
(dc898ab osmux: don't trust AMR FT field) was not correctly
validating the AMR FT field as it was comparing the same
value twice calculated in different ways.
Use osmo_amr_bytes(amrh->ft) to obtain the expected length
and check if it is what we got. Use the output of
osmo_rtp_get_payload() as it also includes the RTP payload
stripping possible extensions.
The ctr field of the osmux header is 3 bits long, make sure we
don't run over that boundary. This should not happen in practise
unless we have to deal with network congestion or broken RTP
stacks, but osmux should not crash in that case.
With the fan-out approach to test multi-batch added int (078d532 tests:
osmux: test multi-batch support), this doesn't need the explicit
skip as there are already gaps to be filled.
With this patch, osmux_xfrm_input() returns 0 (means "message has been
processed") instead of 1 (means "retry") if the RTP message is too big
to fit into one osmux batch. This fixes a likely infinite loop in the
caller, which will retry forever for a message does not fit into the
batch.
Unlikely to happen in normal scenario, as RTP+AMR messages are way
smaller than the interface MTU.
Pablo Neira Ayuso
Martin Hauke