This rename is the first step of moving the associated functions into
libosmocore.
Also, rename gprs_match_* to osmo_match_shift_* to indicate that it is
not just matching the TLV, but also shifting the data portion.
Replace hardcoded protocol discriminator and message type bitmasks with
function calls recently introduced in libosmocore.
Note that the release 98 bitmasks slightly differ from the release 99 bitmasks.
This patch uses the "default" gsm48_hdr_msg_type invocation, thus it depends on
libosmocore whether 98 or 99 bitmasks are used.
In some places, use of the bitmask was erratic. Fix these implicitly by
employing the bitmask functions:
* silent_call.c: silent_call_reroute(): add missing bitmask for MM.
* bsc_msg_filter.c: bsc_msg_filter_initial(): RR vs. MM messages.
* osmo_bsc_filter.c: bsc_find_msc() and bsc_scan_bts_msg(): RR vs. MM
messages.
* bsc_nat_rewrite.c: bsc_nat_rewrite_msg(): SMS vs. CC messages.
* bsc_ussd.c: no bitmask is applicable for the message types used here.
* gb_proxy.c: gbproxy_imsi_acquisition(): missing bit mask for pdisc.
In gprs_gb_parse.c: gprs_gb_parse_dtap(), add a log notice for unexpected
message types.
Currently the parser functions for single information elements are
defined within gprs_gb_parse.c and not exported explicitely. In
addition they are named like libosmocore's TLV parser functions and
do not have a proper name prefix. Since it is planned to use them for
other protocols, they need to be globally accessible.
This patch moves them to gprs_utils.c and renames them.
The new names are:
lv_shift -> gprs_shift_lv
v_fixed_shift -> gprs_shift_v_fixed
lv_shift -> gprs_shift_lv
v_fixed_shift -> gprs_shift_v_fixed
In the long term, these functions should be moved to libosmocore (and
renamed again).
Sponsored-by: On-Waves ehf
Currently the P-TMSI IE in PAGING_PS is not patched.
This commit adds code to patch BSSGP P-TMSI IE in
gbproxy_patch_bssgp independently from the P-TMSI patching at the LLC
layer. It also extends gbproxy_update_link_state_dl to use the IMSI
to find the link_info if the TLLI is not present in the message.
Note that the spec (GSM 08.18, 7.2) requires to use of the P-TMSI
instead of the IMSI to select the MS if that IE is available.
Nevertheless as long as the IMSI is always present in downlink BSSGP
messages and as long as the optional P-TMSI refers to the same MS
(which is the case currently), this is not an issue.
Sponsored-by: On-Waves ehf
Currently, the log level is always LOGL_DEBUG. In case of errors it
would be helpful to use a higher log level.
This patch adds a log_level parameter to gprs_gb_log_parse_context to
let the caller decide about the level.
Ticket: OW#1307
Sponsored-by: On-Waves ehf
This function tries to get an accurate name for the message even if
the parsing has been aborted due to message errors.
The patch also moves the settings of the BSSGP related fields in
parse_ctx from behind to the front of bssgp_tlv_parse, to get more
information in the case of failure. This is now consistent with the
handling of the llc and g48_hdr fields.
Id addition, gprs_gb_log_parse_context now uses the new function to
derive a more accurate message name.
Ticket: OW#1307
Sponsored-by: On-Waves ehf
Currently, ptmsi_enc and new_ptmsi_enc point to the beginning of the
mobile identity. Since all P-TMSI in 04.08 (MM) are encoded this way (1
byte header + 4 byte P-TMSI value). This is different to the P-TMSI
encoding in 08.18 (BSSGP), where the P-TMSI is encoded into 4 byte
without MI header.
This patch changes the code to use pointers to the P-TMSI value,
which is encoded in the same way in both specifications.
Sponsored-by: On-Waves ehf
Currently the parse expects a 'MS network capability' IE with
2 <= length <= 3 which is compliant to GSM 04.08, 9.4.1 but not to
GSM 24.008, 9.4.1 which specifies 3 <= length <= 9. Thus the parser
rejects messages with a length >= 4 (including length field).
This patch relaxes the length check to accept either range by
requiring 2 <= length <= 9.
Ticket: OW#1258
Sponsored-by: On-Waves ehf
That message is currently ignored but should invalidate the TLLI and
de-register the logical link instead.
This patch extends the parser to recognize such messages and to set
the invalidate_tlli flag.
Sponsored-by: On-Waves ehf
Since this message puts the MS into DEREGISTERED state (like a detach
procedure), this message is parsed and the invalidate_tlli field is
set accordingly.
Sponsored-by: On-Waves ehf
gprs_gb_log_parse_context() uses a sequence of LOGP calls to compose
a single message line. This leads to cluttered log output.
This patch replaces all but the first LOGP applications in this
function by applications of LOGPC.
Sponsored-by: On-Waves ehf
Currently a tlli_info entry is deleted when the TLLI gets invalidated
by a Detach message.
This patch introduces the possibility to keep tlli_info entries in
the list. Those entries then have cleared TLLI fields, are marked as
de-registered, and can only be retrieved by a message containing an
IMSI or a P-TMSI.
The following VTY configuration commands are added to the gbproxy
node:
- tlli-list keep-mode never : Don't keep the entries (default)
- tlli-list keep-mode re-attach : Only keep them, when a Detach
message with re-attach required has been received
- tlli-list keep-mode identified : Only keep entries which are
associated with an IMSI
- tlli-list keep-mode always : Keep all entries
Note that at least one of max-length or max-age should be set when
this feature is used to limit the number of entries.
Sponsored-by: On-Waves ehf
Currently the RAI in the LLC part of the message is not updated if
the message has been taken from the list of stored messages. The
reason is, that old_raid_matches is update in
gbprox_process_bssgp_ul() but not in gbproxy_flush_stored_messages().
This patch moves the check to gprs_gb_parse_bssgp() which is called
at both places and where other fields like parse_ctx->tlli are set,
too.
In addition, old_raid_matches is replaced by old_raid_is_foreign
since this is clearer in the case when there is no old RAI at all.
Several RAI patch counter assertions are also added to
test_gbproxy_ra_patching().
Sponsored-by: On-Waves ehf
Currently when patching is enabled and an error happens when
receiving a message from the SGSN, the patched message is sent back
with the PDU_IN_ERROR IE.
This patch modifies gbprox_rx_sig_from_sgsn() to copy the message
before it is patched, so that the original message can be used with
the STATUS message. gbprox_rx_ptp_from_sgsn() does all checks before
the message is patched, so copying is not necessary.
Since gbprox_rx_sig_from_sgsn() is not called for BSSGP UNITDATA
messages and the msgb is already been copied in the gbprox_relay2peer
function, the relative performance impact is expected to be low.
Note that the PDU IE of STATUS messages received from an MS and
forwarded to the SGSN will not be patched. STATUS messages from the
SGSN are only logged and not forwarded to the MS.
Sponsored-by: On-Waves ehf
The gb_proxy shouldn't start to open the box of pandora by including the
gsm_data_shared.h file, particularly not without defining the BSC role.
In any case, as the reserved TMSI is something that's part of the GSM
specs, and not specific to the OpenBSC implementation, it should be part
of libosmocore.
This patch moves several functions and declarations out of gb_proxy.c
to make them reusable by other components and to separate them by
context and task.
Counter enums (prefix is changed to gbproxy_):
enum gbprox_global_ctr -> gprs/gb_proxy.h
enum gbprox_peer_ctr -> gprs/gb_proxy.h
Generic Gb parsing (prefix is changed to gprs_gb_):
struct gbproxy_parse_context -> openbsc/gprs_gb_parse.h
gbprox_parse_dtap() -> gprs/gprs_gb_parse.c
gbprox_parse_llc() -> gprs/gprs_gb_parse.c
gbprox_parse_bssgp() -> gprs/gprs_gb_parse.c
gbprox_log_parse_context() -> gprs/gprs_gb_parse.c
*_shift(), *_match() -> gprs/gprs_gb_parse.c (no prefix)
gbprox_parse_gmm_* -> gprs/gprs_gb_parse.c (static)
gbprox_parse_gsm_* -> gprs/gprs_gb_parse.c (static)
MI testing/parsing (prefix gprs_ added):
is_mi_tmsi() -> gprs/gprs_utils.c
is_mi_imsi() -> gprs/gprs_utils.c
parse_mi_tmsi() -> gprs/gprs_utils.c
TLLI state handling (prefix is changed to gbproxy_):
gbprox_*tlli* -> gprs/gb_proxy_tlli.c
(except gbprox_patch_tlli, gbproxy_make_sgsn_tlli)
Message patching (prefix is changed to gbproxy_):
gbprox_*patch* -> gprs/gb_proxy_patch.c
gbprox_check_imsi -> gprs/gb_proxy_patch.c
Sponsored-by: On-Waves ehf
Harald Welte
Neels Hofmeyr
Jacob Erlbeck