This commit adds code to parse the PTMSI in network originated
messages
- Attach Accept,
- Routing Area Update Accept, and
- P-TMSI Reallocation Command (see below)
to keep track of the TLLI identifying the LLC connection.
The P_TMSI Realloc Command specific code is not being tested yet, so
a corresponding notice is logged when such a message will be
received.
NOTE:
The gbproxy will lose the TLLI when the MS doesn't receive/use
the message (normally the SGSN remembers the old TLLI for some time
to avoid this kind of problem). If this happens the MS will
probably restart the procedure and the network will have to answer
again eventually using one of the above messages which will
re-associate the IMSI with the TLLI before the MS can send a
PDP Context Request message.
Ticket: OW#1192
Sponsored-by: On-Waves ehf
This adds a set of function that parse a single tlv, lv, tv, or v
encoded information element. They are complementary to the *_put
functions defined in libosmocore's tlv.h file. The functions update
the data and data_len fields unless they are a 'match' function and
the tag field doesn't match.
Sponsored-by: On-Waves ehf
Currently the enabled_tllis_count field isn't always decremented when
an element is removed from the TLLI cache list.
This patch adds the missing update and also adjusts the counter
accordingly.
Sponsored-by: On-Waves ehf
Add TLLI cache output to gbprox_dump_peers() to include this info
into the test output.
Separate RA Update Req message handling from Attach Request handling.
Note: There is no test case for the P-TMSI Reallocation Command yet.
Sponsored-by: On-Waves ehf
This commit adds the following counters:
- attach-reqs: Number of Attach Request messages
- attach-rejs: Number of Attach Reject messages
- tlli-cache: Size of the TLLI cache
Sponsored-by: On-Waves ehf
This patch adds IMSI/TLLI connection tracking and uses it to control
APN patching based on the IMSI. TLLI entries can expire based on age
and/or by limiting the TLLI list size.
VTY config-gbproxy:
no core-access-point-name disable APN patching
core-access-point-name none remove APN if present
core-access-point-name APN replace APN if present
core-access-point-name none match-imsi RE remove if IMSI matches
core-access-point-name APN match-imsi RE replace if IMSI matches
tlli-list max-age SECONDS expire after SECONDS
no tlli-list max-age don't expire by age
tlli-list max-length N keep N entries only
no tlli-list max-length don't limit list length
RE is an extended regular expression, e.g. ^12345|^23456
Ticket: OW#1192
Sponsored-by: On-Waves ehf
Currently, all patching state is stored globally in the gbproxy. Thus
the feature cannot be used safely with a concentrating gbproxy (NAT).
This patch moves the state and relevant counters to the gbprox_peer
structure. It adds code to resolve the corresponding peer when
packets are received by looking at BVCI, NSEI, and BSSGP IEs (BVCI,
RAI/LAI/LAC) when the peer is not passed to the
gbprox_patch_bssgp_message() function.
Test cases are also added for the SGSN->BSS case including test cases
with invalid identifiers.
Note that this patch should make it possible to use RAI patching at a
NAT gbproxy as long as the messages are not encrypted.
Ticket: OW#1185
Sponsored-by: On-Waves ehf
This patch adds a Detach Request (MO) / Detach Accept sequence to the
test, followed by another (here invalid) Act PDP Context Req which
should be APN patched.
Sponsored-by: On-Waves ehf
Add a DTAP GMM Information message with an IMSI in the BSSGP header
to enable the association between IMSI and TLLI.
The TLLI of the Routing Area Update messages is set to foreign.
Sponsored-by: On-Waves ehf
Patch the APN in every 'Activate PDP Context Request' message to the
value given by the 'core-access-point-name' command. If the command is
given without an APN, the whole APN IE will be removed. If the
command is being prefixed by a 'no', the APN IE remains unmodified.
The patch mode 'llc-gsm' is added to selectively enable the patching
of LLC session management messages. This is enabled implicitely by
the patch mode 'llc'.
Note that the patch mode should not be set to a value not enabling
the patching of LLC GSM messages ('llc-gsm', 'llc', and 'default' are
sufficient to patch 'Activate PDP Context Request' messages).
Ticket: OW#1192
Sponsored-by: On-Waves ehf
This patch extends the BSSGP patch code to also patch LLC information
elements along with MCC/MNC patching support for the following messages:
- Attach Request
- Attach Accept
- Routing Area Update Request
- Routing Area Update Accept
- P-TMSI reallocation command
Note that encrypted packets will not be patched.
Ticket: OW#1185
Sponsored-by: On-Waves ehf
This adds a feature to patch the BSSGP MNC/MCC fields of messages going
to and coming from the SGSN. To enable this feature, the gbproxy's
VTY commands 'core-mobile-country-code' and/or
'core-mobile-network-code' must be used. All packets to the SGSN are
patched to match the configured values. Packets received from the
SGSN are patched to the corresponding values as last seen from the BSS
side.
Note that this will probably not work with a gbproxy used for several
BSS simultaneously.
Note also, that MCC/MNC contained in a LLC IE will not be patched.
Ticket: OW#1185
Sponsored-by: On-Waves ehf
This patch makes a few changes to improve readability:
- change the sendto() hexdump to start with NS instead of BSSGP
- use more specific message descriptions instead of 'UNITDATA'
- add a title line per test
Sponsored-by: On-Waves ehf
This adds a test case with several messages to test BSSGP patching.
New messages:
- BSSGP/DTAP Attach Request
- BSSGP/DTAP Attach Accept
- BSSGP/DTAP Routing Area Update Request
- BSSGP/DTAP Routing Area Update Accept
- BSSGP/DTAP Activate PDP Context Request
- BSSGP SUSPEND
- BSSGP SUSPEND ACK
Sponsored-by: On-Waves ehf
Currently the terms 'Routing area code' (RAC) and 'Location area
code' (LAC) are used in several places where 'Routing area
identification' (RAI) or 'Location area identification' (LAI) are
meant in fact.
This patch replaces RAC/LAC by RAI/LAI and 'code' by 'identification'
at these places.
Note that RAI := MCC MNC LAC RAC, and LAI := MCC MNC LAC (see GSM
03.03, sections 4.1 and 4.2).
Sponsored-by: On-Waves ehf
The code currently uses an encoded sequence of (hex) 10 20 30 40 50
60 as RAI, for which no bijective mapping to the set of
representations MCC-MNC-LAC-RAC exists.
This patch changes the hard-coded RAI to 11 22 33 40 50 60 which maps
to 112-332-16464-96 (and vice-versa).
Sponsored-by: On-Waves ehf
The gbproxy looses NSEI changes on BVC_RESET and then tries to send
later messages to the wrong (not longer existing) destination.
This patch fixes this by updating the peer's nsei field on BVC_RESET.
Ticket: OW#874
Sponsored-by: On-Waves ehf
This checks the behavior of the gbproxy when the BSS peer changes the
NSEI and the NSVCI. It also tests BVC_RESET and other UNITDATA
messages after these changes between BSS and SGSN and vice versa (via
the gbproxy).
Ticket: OW#874
Sponsored-by: On-Waves ehf
Currently such messages lead to a creation of a new peer with the
SGSN's NSEI, which results in echoing the message back to the SGSN.
This patch modifies this by sending a STATUS response (invalid BVCI)
instead back to the SGSN.
Sponsored-by: On-Waves ehf
This adds a test with a UNITDATA SGSN message that is addressed to an
invalid (unknown) BVCI. The test shows, that the message is echoed to
the SGSN.
Sponsored-by: On-Waves ehf
This adds counters that are incremented when errors are detected.
It also modifies the VTY command 'show gbproxy' so that
'show gbproxy stats' shows the counters.
Sponsored-by: On-Waves ehf
This adds a simulation of the SGSN side of the Gbproxy. The VC is set
up correctly and several combinations of BSSGP messages are sent.
Sponsored-by: On-Waves ehf
This program tests the gbproxy implementation by passing NS messages
to a modified gbproxy that dumps the resulting messages, signals, and
state.
It focusses on testing abnormal situations like port changes.
Ticket: OW#874
Sponsored-by: On-Waves ehf