Stop iterating if the extension bit (0x80) is set but elem is too short
to read another byte.
Related: OS#4393
Change-Id: Id37109dba0f5d40f4b83f0cef9b1dbd9d6bb2c68
The problem with most of the existing gsm0808_* functions in this file
is that they assert() too much, assuming that their callers always pass
perfectly valid input parameters. But this is impossible on practice,
as there can be bugs in complex projects using them, liks osmo-bsc.
It was reported by a customer that a heavily loaded osmo-bsc crashed a
few times, dropping more than 100 sites without network coverage for
a few minutes. As was revealed during the investigaion, it crashed
due to a failing assert at the end of enc_speech_codec():
OSMO_ASSERT(sc->cfg == 0);
The problem is that somehow osmo-bsc is passing an unexpected sc->cfg
value to gsm0808_create_ass_compl2(), in particular 0x02, while the
given sc->type value (GSM0808_SCT_HR1) implies that there cannot be
any configuration bits on the wire.
The reason why and under which circumstances this can be happening
is not clear yet, but what we agreed on so far is that the library
API should be enforcing correctness of the input parameters in a
less agressive way, rather than aborting the process without
letting it any chance to recover.
Modify the original gsm0808_enc_speech_codec[_list]() functions, so
that a negative value is returned in case of an error. Rename them
and add backwards compatibility wrappers, because it's public API.
A separate patch making use of the new API follows next.
Change-Id: I199ffa0ba4a64813238519178155dfc767aa3975
Related: SYS#6229
I believe the gsm0808_* API is mature enough to avoid assert()ing
pointers accepted via function parameters. We can assume the caller
never passes NULL, as we do in almost all public API.
Change-Id: If9b4c92ace68191f5ddcc0a8a340fccbfe0f3dc0
This assert can be dropped because the switch statement above does
not leave any sc->type >= 0x0f for type_extended == false.
Change-Id: Iafb45ed66378f2c9c2480f81371e92c6d1da71a7
Those are available in 3GPP TS 48.008 version 16.0.0 Release 16, section
3.2.2.17 Cell Identifier. It can be seen that we have a collision
between the osmocom non-standard format and the SAI standard one.
This is because CGI-PS is not really a TS 48.008 Cell Identifier, but only
specified in TS 48.018 and has no ID number assigned. The CGI-PS was
added there because the whole osmo-bsc neighbour configuration works
with CellIds to manage neighbours, so it felt natural to extend the APIs
to also provide means to use CGI-PS format (TS 48.018 even refers 48.008
existance and mentions there's no explicit ID).
At the time this Cell Identifier was added, the firstly available number
(11) was taken, which was of course a really bad idea since newer
versions of the spec can at some point use it, which is the case if one
checks for instance TS 48.008 Release 16 SAI Cell Id.
There no perfect way to fix this bad decision at the time, but the
CGI-PS is only used in osmo-bsc and only for RIM related purposes, so by
changing the ID of CELL_IDENT_WHOLE_GLOBAL_PS, we only break RIM under
some specific CIs being used, and when an osmo-bsc is built against
older libosmocore and then used at runtime against a newer libosmocore
(which should be rare).
Hence, the downside is acceptable, and by moving the new ID number to be
ouside of the spec proto TS 48.008 range (4 bits), we make sure we don't
have the same problem again in the future.
Related: SYS#5838
Fixes: ca33a71ca8
Change-Id: Id25e563febdb7640174540136225f399515a0089
Prepare for A5/4 support in osmo-msc.
Add new function gsm0808_create_cipher2() which takes a struct as
argument instead of individual fields. This is akin to e.g.
gsm0808_create_handover_request() below in the file, and allows
backwards compatibly extending the argument list without needing a new
function signature every time.
Add struct gsm0808_cipher_mode_command, as argument list for
gsm0808_create_cipher2(), with kc128 included.
Encode the Kc128 IE in gsm0808_create_cipher2().
Implement gsm0808_create_cipher() by calling gsm0808_create_cipher2().
Change-Id: Ib3906085e0c6e5a496a9f755f0f786238a86ca34
CGI-PS type doesn't exist in GSM 08.08 Cell Id lists. That type of cell
id is osmocom-specific and used internally. In here CGI-PS is
automatically converted to CGI (since the later is an extension of this
one).
The encode/decode_cell_id_u are left intact (comment added) since those
can still be used (and are used by RIM code) to encode/decode TS 48.018
Cell Identifiers.
Related: SYS#4909
Change-Id: Id74f4577c397c1ba696f00395858311bd82cb2c8
It's a static internal function, so it makes sense to have it at start
of its related section.
It will be used by other functions in follow up patches.
Change-Id: I60f61f8f7bb6543feb068bdcee76d3b752565c95
This structure is needed in order to identify a given cell within the
BSS during RIM transactions.
The naming was made up by myself since I couldn't find any naming
reference for this kind of data (RAI + CI).
Since LAI + CI = CGI, then RAI + CI = CGI-PS
osmo_rai_name2 family of functions get a "2" suffix due to already
existing functions handling struct struct gprs_ra_id in gsm48.h
Change-Id: If48f412c32e8e5a3e604a78d12b74787a4786374
In Change-Id Idf2b99e9ef014eba26e3d4f0f38c2714d3a0520a we accidentially removed this
symbol, let's re-introduce it.
Change-Id: I9fbcbcc6619ef0c63d3682fc86adc80045baab02
Function gsm0808_get_cipher_reject_cause() was previously available
in private gsm0808_utils.h. In practice, the exact same code is useful
to extract Cause IE value from any of the many other BSSMAP messages
which use it.
So let's rename it to gsm0808_get_cause() and make it avilable
to everyone to use.
Change-Id: Idf2b99e9ef014eba26e3d4f0f38c2714d3a0520a
The CBSP code assumed that gsm0808_decode_cell_id_u() would return
the number of bytes it has consumed/parsed. But it actually always
returns '0', whcih makes us run in an endless loop :(
Change-Id: I5758af4ec11a827d4b888a3a16c4ec22de90a7d6
When using `OSMO_ASSERT(exp);` clang will warn about
an empty expression because the semi colon was superflous.
Use do {} while (0) to enfore the need of a semi colon.
This might break other test.
Change-Id: I2272d29a81496164bebd1696a694383a28a86434
This function parses a single Cell ID list element into a
'union gsm0808_cell_id_u'. This function is going to be used
by the upcoming CBSP support.
Related: OS#3537
Change-Id: I08b33881667aa32f01e53ccb70d44d5b79c7c986
We have a number of library-internal static global buffers which are
mainly used for various stringification functions. This worked as
all of the related Osmocom programs were strictly single-threaded.
Let's make those buffers at least thread-local. This way every thread
gets their own set of buffers, and it's safe for multiple threads to
execute the same functions once. They're of course still not
re-entrant. If you need re-entrancy, you will need to use the _c()
or _buf() suffix version of those functions and work with your own
(stack or heap) buffers.
Change-Id: I50eb2436a7c1261d79a9d2955584dce92780ca07
IE GSM0808_IE_OSMO_OSMUX_SUPPORT (T, 1 byte) is sent in AoIP appended to
BSSMAP RESET in order to announce the peer that its MGW supports handling
Osmux streams upon call set up.
IE GSM0808_IE_OSMO_OSMUX_CID (TV, T 1 byte & V 1 byte) is sent in AoIP
during call set up:
* MSC->BSC Assignment Request
* BSC->MSC Assignemnt Complete
The 1 byte value contains the local Osmux CID, aka the recvCID aka CID where the
peer sending the Assign Req/Compl will look for Osmux frames on that
call. Hence, the peer receiving this CID value must use it to send Osmux
frames for that call.
As a result, a given call leg BSC<->MSC can have one different Osmux CID
per direction. For example:
* MS => MGW_BSC ==CID 0==> MGW_MSC
* MS <= MGW_BSC <=CID 1=== MGW_MSC
This allows for setups with 256 call legs per BSC on scenarios where NAT
is not a problem, where MSC can have a pool of 256 CID per MGW_BSC (or
remote peer).
Related: OS#2551
Change-Id: I28f83e2e32b9533c99e65ccc1562900ac2aec74e
This function is doing the bulk work of encoding a given Cell
ID List item. gsm0808_enc_cell_id_list2() is modified to be a
wrapper / loop around the new function.
The purpose of this is to expose Cell ID List Entry encoding
so that the upcoming CBSP protocol encoder can re-use this code.
Related: OS#3537
Change-Id: I6cc567798e20365e6587e6b2988e834306d8c80c
We have a habit of returning static buffers from some functions,
particularly when generating some kind of string values. This is
convenient in terms of memory management, but it comes at the expense
of not being thread-safe, and not allowing for two calls of the
related function within one printf() statement.
Let's introduce _c suffix versions of those functions where the
caller passes in a talloc context from which the output buffer shall
be allocated.
Change-Id: I8481c19b68ff67cfa22abb93c405ebcfcb0ab19b
We have a number of static buffers in use in libosmo*. This means
the related functions are not usable in a thread-safe way. While
we so far don't have many multi-threaded programs in the osmocom
universe, the static buffers also prevent us from calling the same
e.g. string-ify function twice within a single printf() call.
Let's make sure there's an alternative function in all those cases,
where the user can pass in a caller-allocated buffer + size, and make
the 'classic' function with the static buffer a wrapper around that
_buf() variant.
Change-Id: Ibf85f79e93244f53b2684ff6f1095c5b41203e05
The function gsm0808_sc_cfg_from_gsm48_mr_cfg() is used to convert a
gsm48 multirate struct into a set of S-bits (S0 to S15). However, the
conversion function currently does not take into account that bit S1
actually stands for four rates at once (Config-NB-Code = 1). Lets make
sure that S1 is only set when the multirate configuration permits all
four required rates.
Change-Id: I6ad531d4e70c2252e32e2bbaca8e14a7ec6d9840
Related: SYS#4470
The function gsm0808_sc_cfg_from_gsm48_mr_cfg() takes an S15 to S0
bitmask and converts that bitmask into an AMR multirate configuration
struct.
Unfortunately the current implementation implements 3GPP TS 28.062,
Table 7.11.3.1.3-2 wrongly in some aspects. Lets fix this.
- Fix wrong interpretation of the bitpatterns
- 5,15K is invalid and must never be selected
- Make sure that no more than 4 rates are selected in the active set
- Extend unit-test
Change-Id: I6fd7f4073b84093742c322752f2fd878d1071e15
Related: SYS#4470
CGI to Cell ID: for example, for Paging, osmo-msc has a CGI for a subscriber
and needs to send out a Cell Identifier IE. Makes sense to add this conversion
here.
Cell ID to CGI: for a Layer 3 Complete, a subscriber sends the current cell in
the form of a Cell Identifier, which we store as a CGI, if necessary enriched
with the local PLMN.
Add enum with bitmask values to identify parts of a CGI, for the return value
of gsm0808_cell_id_to_cgi(). Can't use enum CELL_IDENT for that, because it
doesn't have a value for just a PLMN (and is not a bitmask).
Change-Id: Ib9af67b100c4583342a2103669732dab2e577b04
Add functions to dump LCLS (without GCR) and GCR. Dumping entire struct
results in inconveniently long string hence the separate functions. Both
use talloc functions so they expect caller to take care of providing
proper allocation context and freeing memory.
Change-Id: Ic3609224c8f3282d667e75f68bc20327e36eb9e6
Add
* osmo_lai_cmp() (to use in gsm0808_cell_id_u_matches())
* osmo_cgi_cmp() (to use in gsm0808_cell_id_u_matches())
* gsm0808_cell_id_u_match() (to re-use for single IDs and lists)
* gsm0808_cell_ids_match()
* gsm0808_cell_id_matches_list()
* Unit tests in gsm0808_test.c
Rationale:
For inter-BSC handover, it is interesting to find matches between *differing*
Cell Identity kinds. For example, if a cell as CGI 23-42-3-5, and a HO for
LAC-CI 3-5 should be handled, we need to see the match.
This is most interesting for osmo-msc, i.e. to direct the BSSMAP Handover
Request towards the correct BSC or MSC.
It is also interesting for osmo-bsc's VTY interface, to be able to manage
cells' neighbors and to trigger manual handovers by various Cell Identity
handles, as the user would expect them.
Change-Id: I5535f0d149c2173294538df75764dd181b023312
Most of the time we'll have GCR filled anyway so it make sense to have
it as static parameter instead of a pointer to separately allocated
structure. Update tests to cover both static and dynamic osmo_lcls
allocation variants.
Change-Id: I905c36d8455911c68c30bc429379b7313dd46aea
In 3GPP TS 48.008 the Global Call Reference IE is only used in HANDOVER
REQUEST (§3.2.1.8) and ASSIGNMENT REQUEST (§3.2.1.1) messages which
also include LCLS Config and CSC parameters. Hence, there's no point in
using GCR encode/decode functions alone.
Introduce gsm0808_dec_lcls() and gsm0808_enc_lcls() as trivial wrappers
on top of GCR enc/dec routines which are made static. Adjust tests
accordingly. Test output intentionally left unchanged.
Change-Id: Icfbb2404e1a1d500243e2071173299b557369335
* add functions to encode Global Call. Ref. from TS 29.205 as 3GPP TS
48.008 §3.2.2.115 information element
* add corresponding tests
Change-Id: I82ce0207dc8de50689a8806c6471ad7fbae6219d
At the moment the all gsm0808 cause codes are encoded directly using the
tlv API directly to put a one byte TLV field. This works ok for most
situations where the cause code consists of a single byte. However,
gsm0808 specifies a two byte cause code model where cause codes may be
extended up to two bytes. Instead of implementing the encoding over and
over and again, let's rather have an encoder function we can call.
- Add an encoder function that can generate single byte and extended
cause codeds and makes the length decision automatically.
- Use only this function to append cause codes
Change-Id: I71d58fad89502a43532f60717ca022c15c73f8bb
* add function to generate cipher mode reject with extended (2-byte)
Cause IE
* add function to get (extended) Cause value
* add corresponding (extended cause) test
* update existing (non-extended cause) test
* use enum as a parameter for existing non-extended version to make
interface more unified
Change-Id: Id5509b94a18180a44f45300caaa02b843c166fa3
Related: OS#3187
3GPP_TS_48.008, 3.2.2.103 Speech Codec List states the following:
"The length indicator (octet 2) is a binary number indicating the
absolute length of the contents after the length indicator.
The length depends on the number and type of Speech Codec Elements
to be included. The minimum length of one Speech Codec Element is 1
octet and the maximum length is 3 octets. The maximum number of
Speech Codec Elements within the Speech Codec List is not defined."
This clearly refers only to the length of a single speech codec
element but not on the overall list. So speech codec lists with
length 0 are indeed permitted by the spec.
- Remove the assertion that checks on zero length speech codec
lists.
Change-Id: I1eb1f4466b98bdd26d765b0e4cc690b5e89e9dd6
Related: OS#3657
Add a function to convert S0-S15 bits to struct gsm48_multi_rate_conf,
which hold the codec settings for AMR.
Change-Id: I973736273c236eee84decf15868190e339c3fed4
Related: OS#3548
parameter cfg in gsm0808_sc_cfg_from_gsm48_mr_cfg() is used read only.
Lets add a const to make this clear to the compiler.
Change-Id: I31e8d273b070b0afc446a298299d4f502d6c396b
Add a function to convert struct gsm48_multi_rate_conf, which holds the
codec settings for AMR, to S0-S15 bit representation as defined in
3GPP TS 48.008 3.2.2.49
This resurrects change-id I4e656731b16621736c7a2f4e64d9ce63b1064e98
which was reverted in I9e0d405e303ed86d23703ca6362e958dddb2f861
due to gsm0808_test failing.
The test failure is fixed by properly clearing the struct
gsm48_multirate_cfg prior to running tests (add memset(0)).
Change-Id: Ia782e21c206c15e840226d79b4209d13658ee916
Related: OS#3548
Add a function to convert struct gsm48_multi_rate_conf, which holds the
codec settings for AMR, to S0-S15 bit representation as defined in
3GPP TS 48.008 3.2.2.49
Change-Id: I4e656731b16621736c7a2f4e64d9ce63b1064e98
Related: OS#3548
A loooong time ago, we introduced osmo_panic() as a wrapper around
abort(). The advantage is, that this wrapper can be overridden, and
that it will also work in embedded (bare iron) targets, where the
abort simply translates to an infinite loop.
Change-Id: I5a70eb65952cbc329bf96eacb428b07a9da32433
The idea is to be able to add a gsm0808_cell_id to a gsm0808_cell_id_list2:
first convert it to a list, then re-use gsm0808_cell_id_list_add(). It will be
used by osmo-bsc to manage neighbor-BSS cell identifiers from VTY.
Change-Id: Ibf746ac60b1b1e920baf494b396658a5ceabd788
Add:
- gsm0808_current_channel_type_1()
- gsm0808_permitted_speech()
- gsm0808_chosen_channel()
- gsm0808_channel_type_name()
gsm0808_permitted_speech() is moved from osmo-bsc's bssap_speech_from_lchan();
gsm0808_chosen_channel() is moved from osmo-bsc's lchan_to_chosen_channel();
Rationale: will be re-used by inter-BSC handover, makes sense to keep with the
other gsm0808 utils.
Related: OS#2283 (inter-BSC handover, BSC side)
Change-Id: I8a3cc5d4548e9a78d945d54c69ccced251edcec9
Provide comprehensive API to obtain string representations of Cell Identifiers
and -Lists.
Change gsm0808_test.c to use the new functions (which simplifies the output a
bit), so that we don't duplicate printing code in gsm0808_test.c, and so that
the not-so-trivial printing code is also tested.
In gsm0808_test, also test gsm0808_cell_id_list_name_buf()'s return value and
truncation behavior.
The rationale for gsm0808_cell_id_list_name(), i.e. printing an entire list of
cell identifiers, is that even though the maximum is 127 elements, a list of
more than a few elements is hardly ever expected in practice (even more than
one element isn't actually expected: either "entire BSS" or a single LAC). It
is thus useful to log the entire list when it shows up in Paging and Handover.
Change-Id: I9b2106805422f96c5cc96ebb9178451355582df3
Clarify semantics and micro-optimise for the case of single Cell Identifer IEs.
Test in gsm0808_test.c
So far we have gsm0808_enc_cell_id_list2(), but there also exist instances of
single Cell Identifiers (3GPP TS 48.008 3.2.2.17).
It is possible to decode the same using the cell identifier list API, but this
forces the caller to also keep a full struct gsm0808_cell_id_list2 with all its
127 entries around.
E.g. for handover, there are two Cell Identifiers (Serving and Target); I'd
need two full cell id lists for each, and these would be dynamically allocated
for each handover operation, whether it uses them or not.
Related: OS#2283 (inter-BSC HO, BSC side)
Change-Id: I9f9c528965775698ab62ac386af0516192c4b0cc
Matan Perelman
Oliver Smith
Vadim Yanitskiy
Pau Espin
Harald Welte
Philipp Maier
Neels Hofmeyr