RANAP Security Command can include an encryption IE. If it includes
it the RNC can still ignore it (e.g. unsupported encryption) and
return the Security Command Complete with an choosen encryption IE:
"no encryption".
Validate the encryption element and ensure the encryption is included in
the encryption mask.
Closes: OS#4144
Change-Id: Icfc135c8b8ae862defe7114db492af600c26407f
In order for osmo-hlr to be able to 100% guarantee distinct INDs for CS and PS,
set CN-Domain = CS in all SendAuthInfo Requests.
In Milenage auth, it is highly desirable that osmo-hlr guarantees use of
distinct INDs for CS and PS domains. If an MSC and SGSN attached at the same
time use the same IND bucket to generate Milenage SQN, that collision would
rapidly waste SQNs and load osmo-hlr with requesting new auth tuples on each
CS/PS Complete-Layer3.
So far, osmo-msc did not indicate the CN domain in the GSUP SendAuthInfo
Request, which was neither required nor evaluated. The CN-Domain is only sent
for the UpdateLocation Request that usually follows later.
Related: OS#4318
Change-Id: I22f44068268e62801cadbf6542efaf153423cd65
Substantial parts of the CC / MNCC call establishment were so far completely
missing from the msc_vlr_test_call.c tests. With my new insights on CC and MNCC
procedures, complete the tests.
Root reason: since I am going to re-order the sequence of events to enable
codec negotiation via SDP in MNCC, I want to have comprehensive tests of the CC
procedures to see the effect as diffs in the test output.
Change-Id: Ie995e264eb1e3dd9558a1753ff6f9b55c1d084e1
Recently, the ability to run UTRAN without encryption was added, but the config
for it was tied to the A5 GERAN encryption configuration. This affected
osmo-msc's default behavior of Iu, breaking osmo-msc ttcn3 Iu tests: the ttcn3
test suite sets A5 to 0 (no encryption) but still expects Iu to enable air
encryption. Fix this "regression".
Add a separate vty config option for UEA encryption, even if it does not
provide full granularity to select individual UEA algorithms yet.
As a result, Iu default behavior remains to enable encryption regardless of the
A5 config. UTRAN encryption can be disabled by the new cfg option
"encryption uea 0" alone.
Even though the new vty command already allows passing various combinations of
the UEA algorithm numbers, only '0' and '1 2' are accepted as valid
combinations, to reflect current osmo-msc capabilities.
Revert most changes to the msc_vlr test suite in commit "do not force
encryption on UTRAN" (I04ecd7a3b1cc603b2e3feb630e8c7c93fc36ccd7): use new
net->iu_encryption instead of net->a5_encryption_mask.
Adjust/add to test_nodes.vty transcript tests.
Related: OS#4144
Change-Id: Ie138f2fcb105533f7bc06a6d2e6deccf6faccc5b
Remove the conditions that always enable encryption on UTRAN.
We so far lack an explicit configuration for UTRAN encryption, and this patch
does not add any either. Instead, whether UTRAN encryption is enabled is simply
triggered on whether GERAN has A5 encryption enabled (A5/n with n > 0). Though
GERAN and UTRAN encryption are not technically related at all, this makes UTRAN
behave like GERAN for now, until we implement a proper separate configuration
for UTRAN encryption.
Adjust the msc_vlr_test_* configuration by setting the net->a5_encryption_mask
such that the expected output remains unchanged. A subsequent patch
(I54227f1f08c38c0bf69b9c48924669c4829b04b9) will add more tests, particularly
cases of UTRAN without encryption.
Adjust manual and vty doc.
Related: OS#2783
Change-Id: I04ecd7a3b1cc603b2e3feb630e8c7c93fc36ccd7
3GPP TS 49.008 '4.3 Roles of MSC-A, MSC-I and MSC-T' defines distinct roles:
- MSC-A is responsible for managing subscribers,
- MSC-I is the gateway to the RAN.
- MSC-T is a second transitory gateway to another RAN during Handover.
After inter-MSC Handover, the MSC-I is handled by a remote MSC instance, while
the original MSC-A retains the responsibility of subscriber management.
MSC-T exists in this patch but is not yet used, since Handover is only prepared
for, not yet implemented.
Facilitate Inter-MSC and inter-BSC Handover by the same internal split of MSC
roles.
Compared to inter-MSC Handover, mere inter-BSC has the obvious simplifications:
- all of MSC-A, MSC-I and MSC-T roles will be served by the same osmo-msc
instance,
- messages between MSC-A and MSC-{I,T} don't need to be routed via E-interface
(GSUP),
- no call routing between MSC-A and -I via MNCC necessary.
This is the largest code bomb I have submitted, ever. Out of principle, I
apologize to everyone trying to read this as a whole. Unfortunately, I see no
sense in trying to split this patch into smaller bits. It would be a huge
amount of work to introduce these changes in separate chunks, especially if
each should in turn be useful and pass all test suites. So, unfortunately, we
are stuck with this code bomb.
The following are some details and rationale for this rather huge refactoring:
* separate MSC subscriber management from ran_conn
struct ran_conn is reduced from the pivotal subscriber management entity it has
been so far to a mere storage for an SCCP connection ID and an MSC subscriber
reference.
The new pivotal subscriber management entity is struct msc_a -- struct msub
lists the msc_a, msc_i, msc_t roles, the vast majority of code paths however
use msc_a, since MSC-A is where all the interesting stuff happens.
Before handover, msc_i is an FSM implementation that encodes to the local
ran_conn. After inter-MSC Handover, msc_i is a compatible but different FSM
implementation that instead forwards via/from GSUP. Same goes for the msc_a
struct: if osmo-msc is the MSC-I "RAN proxy" for a remote MSC-A role, the
msc_a->fi is an FSM implementation that merely forwards via/from GSUP.
* New SCCP implementation for RAN access
To be able to forward BSSAP and RANAP messages via the GSUP interface, the
individual message layers need to be cleanly separated. The IuCS implementation
used until now (iu_client from libosmo-ranap) did not provide this level of
separation, and needed a complete rewrite. It was trivial to implement this in
such a way that both BSSAP and RANAP can be handled by the same SCCP code,
hence the new SCCP-RAN layer also replaces BSSAP handling.
sccp_ran.h: struct sccp_ran_inst provides an abstract handler for incoming RAN
connections. A set of callback functions provides implementation specific
details.
* RAN Abstraction (BSSAP vs. RANAP)
The common SCCP implementation did set the theme for the remaining refactoring:
make all other MSC code paths entirely RAN-implementation-agnostic.
ran_infra.c provides data structures that list RAN implementation specifics,
from logging to RAN de-/encoding to SCCP callbacks and timers. A ran_infra
pointer hence allows complete abstraction of RAN implementations:
- managing connected RAN peers (BSC, RNC) in ran_peer.c,
- classifying and de-/encoding RAN PDUs,
- recording connected LACs and cell IDs and sending out Paging requests to
matching RAN peers.
* RAN RESET now also for RANAP
ran_peer.c absorbs the reset_fsm from a_reset.c; in consequence, RANAP also
supports proper RESET semantics now. Hence osmo-hnbgw now also needs to provide
proper RESET handling, which it so far duly ignores. (TODO)
* RAN de-/encoding abstraction
The RAN abstraction mentioned above serves not only to separate RANAP and BSSAP
implementations transparently, but also to be able to optionally handle RAN on
distinct levels. Before Handover, all RAN messages are handled by the MSC-A
role. However, after an inter-MSC Handover, a standalone MSC-I will need to
decode RAN PDUs, at least in order to manage Assignment of RTP streams between
BSS/RNC and MNCC call forwarding.
ran_msg.h provides a common API with abstraction for:
- receiving events from RAN, i.e. passing RAN decode from the BSC/RNC and
MS/UE: struct ran_dec_msg represents RAN messages decoded from either BSSMAP
or RANAP;
- sending RAN events: ran_enc_msg is the counterpart to compose RAN messages
that should be encoded to either BSSMAP or RANAP and passed down to the
BSC/RNC and MS/UE.
The RAN-specific implementations are completely contained by ran_msg_a.c and
ran_msg_iu.c.
In particular, Assignment and Ciphering have so far been distinct code paths
for BSSAP and RANAP, with switch(via_ran){...} statements all over the place.
Using RAN_DEC_* and RAN_ENC_* abstractions, these are now completely unified.
Note that SGs does not qualify for RAN abstraction: the SGs interface always
remains with the MSC-A role, and SGs messages follow quite distinct semantics
from the fairly similar GERAN and UTRAN.
* MGW and RTP stream management
So far, managing MGW endpoints via MGCP was tightly glued in-between
GSM-04.08-CC on the one and MNCC on the other side. Prepare for switching RTP
streams between different RAN peers by moving to object-oriented
implementations: implement struct call_leg and struct rtp_stream with distinct
FSMs each. For MGW communication, use the osmo_mgcpc_ep API that has originated
from osmo-bsc and recently moved to libosmo-mgcp-client for this purpose.
Instead of implementing a sequence of events with code duplication for the RAN
and CN sides, the idea is to manage each RTP stream separately by firing and
receiving events as soon as codecs and RTP ports are negotiated, and letting
the individual FSMs take care of the MGW management "asynchronously". The
caller provides event IDs and an FSM instance that should be notified of RTP
stream setup progress. Hence it becomes possible to reconnect RTP streams from
one GSM-04.08-CC to another (inter-BSC Handover) or between CC and MNCC RTP
peers (inter-MSC Handover) without duplicating the MGCP code for each
transition.
The number of FSM implementations used for MGCP handling may seem a bit of an
overkill. But in fact, the number of perspectives on RTP forwarding are far
from trivial:
- an MGW endpoint is an entity with N connections, and MGCP "sessions" for
configuring them by talking to the MGW;
- an RTP stream is a remote peer connected to one of the endpoint's
connections, which is asynchronously notified of codec and RTP port choices;
- a call leg is the higher level view on either an MT or MO side of a voice
call, a combination of two RTP streams to forward between two remote peers.
BSC MGW PBX
CI CI
[MGW-endpoint]
[--rtp_stream--] [--rtp_stream--]
[----------------call_leg----------------]
* Use counts
Introduce using the new osmo_use_count API added to libosmocore for this
purpose. Each use token has a distinct name in the logging, which can be a
globally constant name or ad-hoc, like the local __func__ string constant. Use
in the new struct msc_a, as well as change vlr_subscr to the new osmo_use_count
API.
* FSM Timeouts
Introduce using the new osmo_tdef API, which provides a common VTY
implementation for all timer numbers, and FSM state transitions with the
correct timeout. Originated in osmo-bsc, recently moved to libosmocore.
Depends: Ife31e6798b4e728a23913179e346552a7dd338c0 (libosmocore)
Ib9af67b100c4583342a2103669732dab2e577b04 (libosmocore)
Id617265337f09dfb6ddfe111ef5e578cd3dc9f63 (libosmocore)
Ie9e2add7bbfae651c04e230d62e37cebeb91b0f5 (libosmo-sccp)
I26be5c4b06a680f25f19797407ab56a5a4880ddc (osmo-mgw)
Ida0e59f9a1f2dd18efea0a51680a67b69f141efa (osmo-mgw)
I9a3effd38e72841529df6c135c077116981dea36 (osmo-mgw)
Change-Id: I27e4988e0371808b512c757d2b52ada1615067bd
Replace locally defined enum ran_type with libosmocore's new enum
osmo_rat_type, and value_string ran_type_names with osmo_rat_type_names.
The string representations change, which has cosmetic effects on the test suite
expectations.
Depends: I659687aef7a4d67ca372a39fef31dee07aed7631 (libosmocore)
Change-Id: I2c78c265dc99df581e1b00e563d6912c7ffdb36b
To avoid leaking structure details into test we sometimes have to
separate value description from actual value. Introduce new macro which
makes that possible and convert old one into trivial wrapper around it.
Change-Id: Ic462297edac4c55689f93cc45771c8b5e2aed864
For hysterical raisins, there are some header files that contain few
declarations, and where the name doesn't reflect the content. Combine them to
new msc_common.h:
- common.h
- common_cs.h
- osmo_msc.h
Change-Id: I9e3a587342f8d398fb27354a2f2475f8797cdb28
In preparation for inter-BSC and inter-MSC handover, we need to separate the
subscriber management logic from the actual RAN connections. What better time
to finally rename gsm_subscriber_connection.
* Name choice:
In 2G, this is a connection to the BSS, but even though 3GPP TS commonly talk
of "BSS-A" and "BSS-B" when explaining handover, it's not good to call it
"bss_conn": in 3G a BSS is called RNS, IIUC.
The overall term for 2G (GERAN) and 3G (UTRAN) is RAN: Radio Access Network.
* Rationale:
A subscriber in the MSC so far has only one RAN connection, but e.g. for
inter-BSC handover, a second one needs to be created to handover to. Most of
the items in the former gsm_subscriber_connection are actually related to the
RAN, with only a few MM and RTP related items. So, as a first step, just rename
it to ran_conn, to cosmetically prepare for moving the not strictly RAN related
items away later.
Also:
- Rename some functions from msc_subscr_conn_* to ran_conn_*
- Rename "Subscr_Conn" FSM instance name to "RAN_conn"
- Rename SUBSCR_CONN_* to RAN_CONN_*
Change-Id: Ic595f7a558d3553c067f77dc67543ab59659707a
When the VLR requests a Ciphering Mode with vlr_ops.set_ciph_mode(), and if we
need a ciph algo flag from a Classmark information that is not yet known
(usually CM 2 during LU), send a BSSMAP Classmark Request to get it.
To manage the intermission of the Classmark Request, add
- msc_classmark_request_then_cipher_mode_cmd(),
- state SUBSCR_CONN_S_WAIT_CLASSMARK_UPDATE,
- event SUBSCR_CONN_E_CLASSMARK_UPDATE.
From state AUTH_CIPH, switch to state WAIT_CLASSMARK_UPDATE. Once the BSSMAP
Classmark Response, is received, switch back to SUBSCR_CONN_S_AUTH_CIPH and
re-initiate Ciphering Mode.
To be able to re-enter the Ciphering Mode algo decision, factor it out into
msc_geran_set_cipher_mode().
Rationale:
In the following commit, essentially we stopped supporting A5/3 ciphering:
commit 71330720b6
"MSC: Intersect configured A5 algorithms with MS-supported ones"
Change-Id: Id124923ee52a357cb7d3e04d33f585214774f3a3
A5/3 was no longer supported because from that commit on, we strictly checked
the MS-supported ciphers, but we did not have Classmark 2 available during
Location Updating.
This patch changes that: when Classmark 2 is missing, actively request it by a
BSSMAP Classmark Request; continue Ciphering only after the Response. Always
request missing Classmark, even if a lesser cipher were configured available.
If the Classmark Update response fails to come in, cause an attach failure.
Instead, we could attempt to use a lesser cipher that is also enabled. That is
left as a future feature, should that become relevant. I think it's unlikely.
Technically, we could now end up requesting a Classmark Updating both during LU
(vlr_lu_fsm) and CM Service/Paging Response (proc_arq_fsm), but in practice the
only time we lack a Classmark is: during Location Updating with A5/3 enabled.
A5/1 support is indicated in CM1 which is always available, and A5/3 support is
indicated in CM2, which is always available during CM Service Request as well
as Paging Response. So this patch has practical relevance only for Location
Updating. For networks that permit only A5/3, this patch fixes Location
Updating. For networks that support A5/3 and A5/1, so far we always used A5/1
during LU, and after this patch we request CM2 and likely use A5/3 instead.
In msc_vlr_test_gsm_ciph, verify that requesting Classmark 2 for A5/3 works
during LU. Also verify that the lack of a Classmark Response results in attach
failure.
In msc_vlr_test_gsm_ciph, a hacky unit test fakes a situation where a CM2 is
missing during proc_arq_fsm and proves that that code path works, even though
the practical relevance is currently zero. It would only become interesting if
ciphering algorithms A5/4 and higher became relevant, because support of those
would be indicated in Classmark 3, which would always require a Classmark
Request.
Related: OS#3043
Depends: I4a2e1d3923e33912579c4180aa1ff8e8f5abb7e7 (libosmocore)
Change-Id: I73c7cb6a86624695bd9c0f59abb72e2fdc655131
Previously the '*#100#' USSD-request was abused in order to
conclude the current subscriber connection. This makes the unit
tests depend on each other, for example, if one break something
in the GSM 09.11 implementation, a half of tests would fail.
Moreover, the further changes in the GSM 09.11 implementation
will make the results less predictable (i.e. session ID, etc.).
So let's introduce a separate unit test with simple request-
response logic, while more complex tests will be in TTCN.
Change-Id: I40b4caac3113263f5a06c861dff5e10d43c319b5
Remove subscribers which fail to send periodic Location Updates from the
list of subscribers known to the VLR. This complements the IMSI detach
procedure: periodic LU expiry triggers an implicit IMSI detach.
Expired subscribers are purged from a periodic timer which iterates
over all subscribers once per minute.
Subscribers with an active connection do not expire. This is controlled
by the subscriber conn FSM which sets a subscriber's the LU expiry timeout
value to GSM_SUBSCRIBER_NO_EXPIRATION while a connection is active.
Add support for fake time with osmo_clock_gettime() to msc_vlr tests.
This functionality existed in OpenBSC but was lost during the nitb split.
This code took some inspiration from the OpenBSC implementation.
Related: OS#1976
Change-Id: Iebdee8b12d22acfcfb265ee41e71cfc8d9eb3ba9
When sending a BSSMAP Clear or Iu Release, do not immediately discard the conn,
but wait until a BSSMAP Clear Complete / Iu Release Complete has been received.
Hence we will no longer show in the log that an incoming Release/Clear Complete
belongs to an unknown subscriber, but will still be around to properly log the
release.
Related: OS#3122
Change-Id: Ie4c6aaba3866d6e5b98004e8870a215e8cf8ffc1
Clearly distinguish between Ciphering Mode Command on GERAN and Security Mode
Control on UTRAN.
Cosmetic: explicitly verify the key strings in the testing code (not only in
the expected output).
Change-Id: Ica93ed06c4c63dc6768736d25231de8068001114
Three recently merged commits take the msc_vlr_tests in a wrong direction.
The IMSI is usually encoded in the hex streams. The rationale behind hex
streams is that it is a) easily copied from a wireshark trace and b) exactly
the bytes as sent by an actual phone. It is hard to parameterize the IMSI
because we would have to employ our encoding functions, which I intentionally
want to keep out of the loop here.
The test number should not appear in the normal test output, so that adding a
test or changing their order does not affect expected output for following
tests. The nr is simply for manual invocation, only seen when invoked with -v.
Revert
- "VLR tests: always print test parameters"
b0a4314911.
- "Expand VLR tests"
d5feadeee8.
- "Move IMSI into test parameters"
093300d141.
Change-Id: Ie1b49237746751021da88f6f07bbb9f780d077c9
For each test print:
* the test number
* IMSI
Unfortunately tests are organized in such a way that we don't know the
number of particular test in advance. Nevertheless, it make sense to
always print it regardless of -v option presense.
Related: OS#2864
Change-Id: I2e1d7701f5322d2311f32b796148a8b414f53b8e
This makes test routines more flexible and allows to easier re-use them
for tests with different IMSIs.
Change-Id: I74d46fdb7e87dc04c6b82a0b6f3ce6bef60bde58
Related: OS#2864
On MT call, there is a bug in CC conn use which leads to an early free and
use-after-free.
Add msc_vlr_test_call to show both MO and MT call legs separately and reproduce
the failure. It is visible in a sanitizer build (on debian 9).
A subsequent patch will fix the bug: If0659a878deb383ed0300217e2c41c8c79b2b6a5
Related: OS#2672
Change-Id: I6c3ca0c660388b1e2c82df17ec540c846201b0c7
This was originally a long series of commits converging to the final result
seen in this patch. It does not make much sense to review the smaller steps'
trial and error, we need to review this entire change as a whole.
Implement AoIP in osmo-msc and osmo-bsc.
Change over to the new libosmo-sigtran API with support for proper
SCCP/M3UA/SCTP stacking, as mandated by 3GPP specifications for the IuCS and
IuPS interfaces.
From here on, a separate osmo-stp process is required for SCCP routing between
OsmoBSC / OsmoHNBGW <-> OsmoMSC / OsmoSGSN
jenkins.sh: build from libosmo-sccp and osmo-iuh master branches now for new
M3UA SIGTRAN.
Patch-by: pmaier, nhofmeyr, laforge
Change-Id: I5ae4e05ee7c57cad341ea5e86af37c1f6b0ffa77
osmo-nitb becomes osmo-msc
add DIUCS debug log constant
add iucs.[hc]
add msc vty, remove nitb vty
add libiudummy, to avoid linking Iu deps in tests
Use new msc_tx_dtap() instead of gsm0808_submit_dtap()
libmgcp: add mgcpgw client API
bridge calls via mgcpgw
Enable MSC specific CTRL commands, bsc_base_ctrl_cmds_install() still needs to
be split up.
Change-Id: I5b5b6a9678b458affa86800afb1ec726e66eed88
Alexander Couzens
Philipp Maier
Neels Hofmeyr