Commit Graph

37 Commits

Author SHA1 Message Date
Pau Espin ea8dbddab1 Move tbf ul_ack_state to osmocom FSM
Related: OS#2709
Change-Id: Icf23bf5a4b85fbcbf1542cebceb76b9ba7185d30
2021-08-23 17:14:23 +02:00
Pau Espin afe189e802 Get rid of lots of code only used by tests
There are 2 methods "rcvd_dl_ack()" in osmo-pcu code. One is used by
osmo-pcu itself, and the other is only used in tests.
Changing the tests to use the same method as osmo-pcu allows removing
the second one, and with it, a lot of code and complexity out of
osmo-pcu.

Change-Id: I14d9312cb61534dc97fca83141b9c0cd933c9206
2021-08-23 17:14:23 +02:00
Pau Espin 49a2f404e8 replace dl_ass_state with osmocom FSM
Related: OS#2709
Change-Id: Ia33418478e17986a316ffda48b091030f53fa371
2021-08-23 17:14:22 +02:00
Pau Espin 6ad11a6990 Replace ul_ass_state with osmocom FSM
Related: OS#2709
Change-Id: Id414eafe9c04a9a8759c6fb1a483bf2ee093a4d2
2021-08-23 17:14:22 +02:00
Pau Espin 2ab840a1fa Make WaitIndication T3172 configurable
Tbftest expectatins need to change because 5000/20 = 250 < 255, hence
the message is now sent as units of 20ms instead of seconds.

Related: OS#3928
Change-Id: I48b34b94b1a5dfb046a3a6cf8a0d944a7c9b6754
2021-04-26 17:53:09 +02:00
Pau Espin 25ebf3c8f9 Make use of T3142 received from BTS
Related: OS#3928
Change-Id: I4e26f181db9693d3a267a879e2aebda12eab2a8c
2021-04-26 14:10:11 +02:00
Pau Espin Pedrol 952cb3d5d7 nacc: Implement Pkt Cell Change Continue retransmission
Use the fact that the MS must answer the RRBP of the Pkt Cell Change
Continue with a CTRL ACK to find out whether the message was received
successfuly or a retransmission is potentially required.

3GPP TS 44.060:
"""
When the mobile station receives the PACKET CELL CHANGE ORDER or
the PACKET CELL CHANGE CONTINUE message the mobile station shall
transmit a PACKET CONTROL ACKNOWLEDGMENT message in the specified
uplink radio block if a valid RRBP field is received as part of the
message; the mobile station may then switch to a new cell.
"""

Related: SYS#4909
Change-Id: I7cc28922e71699598da0ef6eb90136a47d3c002f
2021-02-03 08:34:04 +00:00
Pau Espin c0a250d17d Introduce NACC support
A new nacc_fsm is introduced per MS object, with its partner priv
structure struct nacc_fsm_ctx, which exists and is available in the MS
object only during the duration of the NACC procedure.

The NACC context is created on an MS whenever a Pkt Cell Change
Notification is received on Uplink RLCMAC, which asks for neighbor
information of a given ARFCN+BSIC.

First, the target ARFCN+BSIC needs to be translated into a CGI-PS
(RAC+CI) address. That's done by asking the BSC through the Neighbour
Resolution Service available in osmo-bsc using the CTRL interface.

Once the CGI-PS of the target cell is known, PCU starts a RIM RAN-INFO
request against the SGSN (which will route the request as needed), and
wait for a response containing the SI bits from the target cell.

After the SI are received, the scheduler is instructed to eventually
poll a TBF for the MS originating the CCN, so that we can send the SI
encapsulated into multiple Packet Neighbor Cell Data messages on the
downlink.

One all the SI bits are sent, the scheduler is instructed to send a
Packet Cell Change Continue message.

Once the message above has been sent, the FSM autodestroys itself.

Caches are also introduced in this patch which allows for re-using
recently known translations ARFCN+BSIC -> CGI-PS and CGI-PS -> SI_INFO
respectively.

Change-Id: Id35f40d05f3e081f32fddbf1fa34cb338db452ca
2021-01-29 12:59:30 +01:00
Pau Espin 7d0f9a0ec3 Dl TBF: Get rid of LLC UI dummy blocks following other data
According to:
* 3GPP TS 44.060 version 16.0.0 "9.3.1a Delayed release of downlink Temporary Block Flow"
* 3GPP TS 44.064 version 16.0.0 "6.4.2.2 Unconfirmed Information (UI) Dummy command"

LLC UI Dummy frames are to be used when there no more data to send, only
in order to delay the release of a TBF. Hence, while not incorrect per
se, makes no sense to send those LLC UI Dummy frames inserted into
rlcmac blocks which already contain other LLC frames, since the MS in
that case is already being kept active.
It only makes sense to send those LLC UI Dummy frames when we have
nothing else to send, that is, alone inside a RLCMAC block without other
LLC frames.

Related: OS#4849
Change-Id: Ifae1a7b2b3dfad8df19585063088ba0df2749c8f
2020-12-01 15:57:37 +01:00
Vadim Yanitskiy db56a3563e encoding: use CSN.1 codec to generate Packet Uplink Assignment
It's quite odd to see that in write_packet_downlink_assignment()
we initialize an 'RlcMacDownlink_t', so then the caller can use
the power of CSN.1 codec to generate the final sequence of bytes
to be transmitted, while in write_packet_uplink_assignment() we
already compose the final RLC/MAC message straight away using
the low-level bitvec API (like bitvec_write_field()).

I guess the reason is that at the time of writing this code, the
CSN.1 codec was not stable enough, so it was safer to generate
the message 'by hand'.  This would also explain why we *decode*
the final RLC/MAC message in create_ul_ass() right after encoding.

Rewrite write_packet_uplink_assignment(), so now it initializes
a caller-provided 'RlcMacDownlink_t' structure.  Given that it's
allocated on heap using talloc_zero(), do not initialize presence
indicators of fields that are not present in the message.

This would facilitate handling of frequency hopping parameters
in the upcoming changes, in particular we can now introduce a
function that would compose Frequency Parameters IE for both
write_packet_{downlink,uplink}_assignment().

Tested manually by running a GPRS-enabled network, as well as by
running test cases from ttcn3-pcu-test => no regressions observed.

Change-Id: I2850b91e0043cdca8ae7498a5fc727eeedd029b6
Related: SYS#4868, OS#4547
2020-09-08 02:47:02 +07:00
Vadim Yanitskiy 1156776572 encoding: pass pdch slot directly to encoding functions
In order to be able to encode frequency hopping parameters, let's
pass a const pointer to 'gprs_rlcmac_pdch' (PDCH slot) directly,
instead of passing all related parameters separately.

Change-Id: I6bccad508f0fdccc4a763211008dd847a9111a8d
Related: SYS#4868, OS#4547
2020-08-24 10:53:08 +00:00
Vadim Yanitskiy a76cdaceb2 encoding: use bool for use_egprs in write_packet_uplink_assignment()
Change-Id: Iab4fb44c666a0d4fe8c98f5ff9221e23a6f1f2fa
2020-08-24 10:53:08 +00:00
Vadim Yanitskiy c0ddaa94e6 encoding: constify 'tbf' in UL/DL assignment functions
Change-Id: I9b80ce22914a355592502c936046b233c3ba216d
2020-08-24 10:53:08 +00:00
Neels Hofmeyr 59fc0bda6e paging: pass struct osmo_mobile_identity, not encoded IE bytes
In get_paging_mi(), before this, an encoded buffer of Mobile Identity bytes is
returned. Code paths following this repeatedly decode the Mobile Identity
bytes, e.g. for logging. Also, in get_paging_mi(), since the TMSI is read in
from a different encoding than a typical Mobile Identity IE, the TMSI was
manually encoded into a typical Mobile Identity IE. This is essentially a code
dup of osmo_mobile_identity_encode(). Stop this madness.

Instead, in get_paging_mi(), return a decoded struct osmo_mobile_identity. Code
paths after this use the struct osmo_mobile_identity directly without repeated
decoding.

At the point of finally needing an encoded Mobile Identity IE (in
Encoding::write_paging_request()), do a proper osmo_mobile_identity_encode().

Since this may return errors, add an rc check for the caller of
write_paging_request(), gprs_rlcmac_paging_request().

A side effect is stricter validation of the Mobile Identity passing through the
Paging code path. Before, invalid MI might have passed through unnoticed.

Change-Id: Iad845acb0096b75dc453105c9c16b2252879b4ca
2020-08-24 01:12:16 +00:00
Pau Espin 2ae8337669 Get rid of class GprsCodingScheme
We have same kind of object splitted into two layers, in coding_scheme
and gprs_coding_scheme. Let's merge them together and get rid of the
class, which is not really useful because it's only a set of functions
operating on one enum value.

This change also fixes gcc 10.1.0 error about memseting a complex type
in rlc.h init().

Change-Id: Ie9ce2144ba9e8dbba9704d4e0000a2929e3e41df
2020-05-20 11:07:07 +00:00
Pau Espin b2653fe619 Move gsm_rlcmac.cpp -> .c
Original file from wireshark.git (packet-gsm_csn1.c) is being built and
maintained as a C file. There's no real need for us to maintain it as a
C++, and doing so will make both files derive over time (as already
happened). Let's keep it as a C compiler (which btw seems to be more
strict) to make it easier to port patches back and forth wireshark.git.

Take the chance to move some declarations we added to csn1.h to be able
to build it out of wireshark. Let's keep those in a separate header file
to ease looking for differences.

Change-Id: I818a8ae947f002d35142f9f5473454cfd80e1830
2020-03-30 10:08:02 +00:00
Pau Espin 5530f12f71 Allow Gb PAGING-PS without P-TMSI
P-TMSI is optional IE, but IE is mandatory and hence always available.
Since the encoding is actually a Mobile Identity, the IMSI is used in
case P-TMSI is not available.

Change-Id: I4dbf8db04e81f98352a42ce34a5d91326be9bfd1
2020-01-06 10:26:46 +00:00
Alexander Couzens 3a499f3cb2 Encoding: drop struct gprs_rlcmac_bts* from all functions
The bts is not used at all.

Change-Id: Ia07755e825913a16352ab13f6cf55f2918de8681
2019-06-24 13:48:43 +00:00
Max fc8afc2f33 Clarify write_immediate_assignment() signature
* remove unused variable
* use bool for boolean types
* add clarification comments

Change-Id: I363445063e2d873d9194b2a5924b9e59b8b7ea53
2019-02-19 18:58:04 +01:00
Max a4f570fe7a window: move encoding into functions
* move window size encoding and writing into separate functions
* introduce necessary TBF wrappers to avoid direct m_window access

This is part of preparation work to move to separate UL/DL windows.

Related: OS#1759
Change-Id: I60184d5049bc7d7b119df5a9eb82d1c4b788c840
2018-01-04 10:15:59 +00:00
aravind sirsikar ed3413e397 Handle packet access reject during EPDAN/PDAN with channel description
When PDAN/EPDAN with channel description is received, PCU will generate the
packet access reject if no resources are present. The encoding is done
based on section 7.1.3.2.1 and 8.1.2.5 of 44.060 version 7.27.0 Release 7.
This patch also includes the test case to validate the generated
packet access reject message.

This patch is integration tested on Osmo-trx setup with Ettus B210 board
and LG F70 MS with some simulation code changes in Osmo-pcu.

Change-Id: I096a3bb44a65533b9e9b091925dd5f70a8696d6
2016-11-11 17:15:10 +05:30
aravind sirsikar c0c3afd079 Handle Immediate assignment reject
When RACH is received, PCU will generate the Immediate assignment reject
message if no resources are present. The encoding is done based on section
9.1.20 of 44.018 version 11.7.0 Release 11. This patch also includes the
test case to validate the generated Immediate assignment reject message.

This patch is integration tested on Osmo-trx setup with Ettus B210 board
and LG F70 MS with some simulation code changes in Osmo-pcu.

Change-Id: I3d33e2b9746fa4f338fad0e6b63b1c5f07de6f9b
2016-11-09 16:27:00 +05:30
bhargava 465f5bbb6f Update the function immediate assignment for EGPRS
Encode the EGPRS fields of immediate assignment message in uplink
when EGPRS PACKET CHANNEL REQUEST (11 bit RACH) is received.
The series of patches for 11 bit RACH are dependent on libosmocore
and osmo-bts patches for 11 bit RACH.

Change-Id: Ie5e309156e5dbbb6add74a1b4d257c4ee2332e52
2016-09-16 05:55:41 +00:00
Alexander Couzens 6f0dc96929 encoding/rlc_copy_from_aligned_buffer: export written payload bytes via an argument
Require to count statistics for rlc_dl_payload_bytes.

Change-Id: I0e622acb1f13f7489946baf049de4ba1cde6a1fc
Reviewed-on: https://gerrit.osmocom.org/142
Tested-by: Jenkins Builder
Reviewed-by: Holger Freyther <holger@freyther.de>
2016-06-07 10:48:35 +00:00
Jacob Erlbeck 2647a337a8 encoding: Redesign Encoding::write_immediate_assignment API
The EGPRS support will need more information to encode the IMMEDIATE
ASSIGMENT. Instead of adding more parameters pass a pointer to the
TBF unless an SBA shall be done (indicated by tbf == NULL). All
values that can be derived from the TBF and are not needed for an SBA
are removed from the parameter list.

Return a negative value on error.

Sponsored-by: On-Waves ehf
2016-02-08 00:45:38 +01:00
Jacob Erlbeck 6b356a58d1 tbf: Use TLLI as ID if TFI not yet assigned
Currently the old TFI is always used as ID when a
PACKET DOWNLINK ASSIGNMENT is generated. This fails
if the old TBF has not been fully assigned yet. The
MS will then ignore the PDA.

This commit changes write_packet_downlink_assignment to accept
an additional parameter old_tfi_is_valid and uses the new TBF's
TLLI instead of the olf TFI if that parameter is set to false.

Sponsored-by: On-Waves ehf
2016-02-08 00:45:38 +01:00
Jacob Erlbeck f2694b74c9 tbf: Add check_polling/set_polling
Currently the checks for and the actual polling is done in several
places by copy & paste of several lines of code. This hinders changes
of they polling is handled internally and also is likely source of
programming mistakes.

Separate this into a check_polling function, that checks whether
polling is possible and returns the FN and the RRBP to be used in
that case. Otherwise the cause is logged (LOGL_DEBUG) and a negative
error value is returned. There are no other side effect beside the
logging.

If the call is successful, the set_polling method can be used to
actually register the polling.

Extend the encoder functions' parameters lists by an rrbp parameter.

Sponsored-by: On-Waves ehf
2016-02-08 00:45:38 +01:00
Jacob Erlbeck 5058bd6e9e edge: Select implementation by mode in rlc_data_to_dl_append
Currently the GPRS data block encoding is applied to every
coding scheme, even if an MCS is selected.

This commit renames the actual encoding function to
rlc_data_to_dl_append_gprs (not exported) and puts
selection code into Encoding::rlc_data_to_dl_append. This
requires an additional cs argument.

Sponsored-by: On-Waves ehf
2016-02-05 13:46:21 +01:00
Jacob Erlbeck 14bb0947b4 edge: Add Encoding::rlc_data_to_dl_append
This function appends a single chunk to an RLC downlink data block.
The implementation is basically taken from the
gprs_rlcmac_dl_tbf::create_new_bsn method without the TBF related
functionality and any side effects.

Note that it still only supports GRPS.

Sponsored-by: On-Waves ehf
2016-02-05 13:26:34 +01:00
Jacob Erlbeck f0e403911d edge: Add encoder for downlink RLC data blocks
Currently the (GPRS) RLC block encoding is done by setting the
header fields directly in gprs_rlcmac_dl_tbf::create_new_bsn.
This is much more complex with EGPRS, since the data fields are
not byte aligned, the header formats depend on the header type,
and the mapping of bits to bytes is LSB first.

This commit adds Encoding::rlc_write_dl_data_header which writes
the header according to the given gprs_rlc_data_header structure.
Encoding::rlc_copy_from_aligned_buffer is also added to copy
byte sequences into the message.

Note that the actual encoding of data units is not yet present.

Sponsored-by: On-Waves ehf
2016-02-05 13:26:34 +01:00
Jacob Erlbeck 166c9fc827 edge: Support EGPRS in write_packet_downlink_assignment
Add an use_egprs parameter to write_packet_downlink_assignment
and add the EGPRS related fields if it is set to true. The
window size is fixed at 64 blocks, link quality measurement
reports have been disabled, and the other optional fields are not
present.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:14 +01:00
Jacob Erlbeck 5ffbb2744f encoding: Remove RlcMacDownlink_t based write_packet_uplink_ack
This is the CSN1-encoder based variant, which has been replaced and
is no longer being used.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:13 +01:00
Jacob Erlbeck 37005a165d encoding: Add bitvec based write_packet_uplink_ack
The current write_packet_uplink_ack implementation is based on the
CSN.1 encoder which makes it difficult to do the bitmap encoding for
EGPRS.

Add a new implementation based on bitvec functions to create the
PACKET UPLINK ACK/NACK messages.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:13 +01:00
Jacob Erlbeck 76d767cbe8 edge: Support EGPRS in packet uplink assignment message
Currently the Encoding::write_packet_uplink_assignment method only
supports the GPRS variant of the message.

This commit adds the missing EGPRS variant to the encoder.

Sponsored-by: On-Waves ehf
2015-11-30 12:20:36 +01:00
Daniel Willmann f55e58f5cf encoding: Change function signature to use UL TBFs where it makes sense
encode_rbb() and write_packet_uplink_assignment are only called with UL
TBFs so change the function signature to reflect that.

Ticket: SYS#389
Sponsored by: On-Waves ehf
2014-08-07 16:12:05 +02:00
Daniel Willmann 5241c1a018 encoding: Factor out encode_rbb to help testing 2013-12-12 11:03:13 +01:00
Holger Hans Peter Freyther 63f29d6f73 encoding: Move the functions into the encoding class
Add some TODO to this class. E.g. they could all work on the
bitvec and the parameter handling could better.
2013-10-30 21:24:10 +01:00