This patch unifies the TLLI tracking for all LLC messages. The TLLI
state handling is moved into separate functions.
Only Detach Accept messages are taken into account to release a TLLI,
which is safe but not optimal.
Sponsored-by: On-Waves ehf
Currently, parsing and optionally patching is done in the same
functions (e.g. gbprox_patch_gmm_attach_req()).
This patch moves the patching code out of these functions into
gbprox_patch_llc() and just stores pointers to the relevant data
areas into parse_ctx. Consequently the len_change parameter is
removed and the _patch_ in the function's names is renamed to
_parse_. In addition, the patching_is_enabled checks and counter
increments are moved out of these functions, too.
Sponsored-by: On-Waves ehf
Currently gbprox_register_tlli() is a rather complex function.
This patch splits it into several smaller functions to ease reviewing
and maintaining it.
Sponsored-by: On-Waves ehf
This adds a unit test for gbprox_register_tlli() and
gbprox_remove_stale_tllis().
The dump_peers() function is extended by a cfg parameter to support
a non-global gbproxy_config.
Done with Jacob
This comparison bit-ored the TLLI with 0xc000 instead of 0xc000000.
Since this has never worked properly yet and since normalizing to
local TLLIs doesn't seem sensible here, the comparison is removed
entirely.
Sponsored-by: On-Waves ehf
In these functions we assume that peer is not NULL. Add a compiler
attribute in the hope that either coverity or GCC/Clang will help
us to find a misusage.
Done with Jacob
Global state prevents us from writing simple units tests for
single routines. Go through the code and add pointers to the
gbproxy configuration. Only the vty and the test code remain
using the global gbproxy instance.
We intend to move some of these routines to libosmocore but to avoid
a feature symbol clash we are prefixing these routines with gprs_.
Done with Jacob
The application is called gbproxy but the structures and functions
were inconsistently named as either gbprox or gbproxy. Rename all
structures to use gbproxy.
Done with Jacob
Move the global data into the struct and use it. gbprox_reset will
first free data and then re-initialize the structure. This code is
used by the unit test.
Done with Jacob
This commit moves the fixing code of the length field of the LLC
information element to the BSSGP patching level since that is not a
part of LLC itself.
Sponsored-by: On-Waves ehf
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
Add a struct containing context information from the parts of the
message that have been parsed already. A pointer to this (temporary)
struct is passed to parse/patch functions.
Sponsored-by: On-Waves ehf
Currently the patching code directly accesses the single bytes to
parse the LLC/DTAP messages.
This patch uses the shift functions instead to parse tlv and similar
structures.
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
These commands manage the TLLI list used to decide whether an APN
shall be patched or not. Note that this list is (currently) only
maintained if IMSI matching is used.
VTY commands (enable node):
show gbproxy tllis show all TLLI entries
delete-gbproxy-tlli NSEI stale purge all stale entries
delete-gbproxy-tlli NSEI imsi IMSI purge entry with the IMSI given
delete-gbproxy-tlli NSEI tlli TLLI purge entry with the TLLI given
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
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 parameter is not used (the methods are always called with an
argument of 1 in the third position). Thus the parameter is removed
completely.
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 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
This adds the option to delete all BVC peers and/or NS_VC with a
given NSEI with a single command. Static (configured) NS-VC are not
affected. In addition, all connections for this NSEI that can be
deleted by this command can be listed without deleting them by
appending 'dry-run' to the command.
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
Add the unused attribute to peer_free() that isn't used currently.
Change 'RAC' to 'NSEI' in the log message, since the latter has been
examined before the log message is generated.
Sponsored-by: On-Waves ehf
Currently in most places in gb_proxy.c a reference to a NS-VC object
is used where the peer is meant instead. The patch changes this by
using the NSEI instead in these cases.
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
The lines 461 and 303 were producing unaligned memory access as
the BVCI was not aligned properly. Introduce a tlvp_val16_unal to
read 16bit from the data, use memcpy to the stack to make sure
that it is working in the aligned and unaligned case.
Instead of direct function calls to individual functions, we now
generate primitives (osmo_prim) and send them to one
application-provided function "bssgp_prim_cb()"