Commit Graph

6170 Commits

Author SHA1 Message Date
Max 4e4ddff4c2 gbproxy: log signal value as text
Change-Id: I6ed923f5c60a8d64305f4b8e90d1362d6510e1c5
2017-08-27 02:33:50 +02:00
Max f6450bb753 gbproxy: log unhandled BSSGP PDU as text
Change-Id: Ibe3c8bd353b3a178e26b0936f25b2e1959f9990c
2017-08-27 02:33:50 +02:00
Pau Espin d5c4339a58 libmsc: Fix wrong handling of user_message_reference parameter
libsmpp34 already converts received TLV integer values to native
endianess in libsmpp34_(un)pack.

Converting them again at receive time swaps the 2 bytes of
user_message_reference, then using a wrong value. As GSM03.40 spec
uses only 1 byte for the id, then only the high byte of the initial
value is used and eventually sent back to the ESME. Again, at that time,
htons() is not needed because libsmpp34 already handles that part.

See OS-#2429 for more details.

Change-Id: If748548a4a223e529a1110c89e483b599b406e8b
2017-08-27 02:33:50 +02:00
Pau Espin 7e16e7299a smpp: Fix compilation warning
I already stumbled into 2 compilation environments which had Werror
enabled for -Wmaybe-uninitialized and the build failed, so let's
workaround this warning.

| smpp_openbsc.c: In function 'handle_smpp_submit':
| smpp_openbsc.c:216:9: error: 'sms_msg_len' may be used uninitialized in this function [-Werror=maybe-uninitialized]
|    memcpy(sms->user_data, sms_msg, sms_msg_len);
|          ^
| smpp_openbsc.c💯15: note: 'sms_msg_len' was declared here
|   unsigned int sms_msg_len;
|                ^
| cc1: some warnings being treated as errors

Change-Id: I0901ddadb5f72e1585cb1797ac22c8ab95e83146
2017-08-27 02:33:50 +02:00
Pau Espin f5816f6f5b sgsn_test: Fix wrong definition of wrap func
Commit 058cd573d8 added 2 new pointer parameters to
gprs_subscr_request_auth_info, but forgot to update wraps of the
function in sgsn_test.

I catched this today because openbsc build test sgsn_test was failing.
Closed look up to the logs showed:
Assert failed (auts != NULL) == (auts_rand != NULL) openbsc/openbsc/src/gprs/gprs_subscriber.c:791

Change-Id: Ie9e4af6da0339536fb20ca0b7bbcf6f485bd522c
2017-08-27 02:33:49 +02:00
Keith Whyte 04982bd272 LIBMSC: Use sms->text, not sms->user_data to construct report body
gsm_04_11.c sms_report_alloc()

Use the sms->text, not the sms->user_data to construct the report body.
This also prevents the potential output of non printable characters to
the log and or vty.

Change-Id: Id51bc9483ad6f52d6da74135605cfd12434c7c96
2017-08-27 02:33:49 +02:00
Keith Whyte ab9d8633c8 LIBMSC: Place correct dst address in status report
gsm_04_11.c: gsm340_gen_sms_status_report_tpdu()

When we construct the status report PDU, use sms->src
instead of sms->dst as the destination address
This way we tell the MS that the message was delivered
to the destination and not to itself.
This is relevant for phones that display a textual
representation of the delivery report.

Change-Id: I2d4f87ac777465de9bfb5a775a789a2691755ee9
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 4f03b47d84 libmsc: use SMPP34_DELIVERY_RECEIPT_* in libsmpp34
Use new definitions in libsmpp34 to set the registered_delivery field
accordingly, as provided by I5b3afff1b3b77cccd949e0606914c7ac3ba6114c.

Moreover, do not set this header field to zero if status reports are
off, the deliver_t structure has been already zeroed so this not
required.

Change-Id: Ie78e17323796120f576b9c0e1bc5ccc32da8ee12
2017-08-27 02:33:49 +02:00
Harald Welte 2d23e901a0 increase libsmpp34 version requirement to 1.12
Only 1.12 contains some of the #defines that we're using with recent
commits.

Change-Id: I3743b10a1a5d2f1d42a61204273c1d00dc22b600
2017-08-27 02:33:49 +02:00
Harald Welte 586e6819eb Migrate from gprs_apn_to_str() to libosmocore osmo_apn_to_str()
In 2015, Jacob moved/copied related functions to libosmocore, but
for some reason didn't remove the copies here.  Let's follow-up on
that and remove duplicated code.

The libosmocore commit introducing osmo_apn_to_str() was
8114294bf29ac6e44822c0ae43d4b0819f11b022

Change-Id: I7315ffcbed8a54cca2056f313bb7783ad82d0ee9
2017-08-27 02:33:49 +02:00
Harald Welte 0f7013266b sgsn_vty: Don't assume pdp->lib is always valid
We can only print libgtp pdp information if a library context is
attached to this pdp context.  This is not always the case,
particuarly during some teardown scenarios.

Change-Id: Ia3184877f9709db65f5f93a98403f2ef5b04a8ca
2017-08-27 02:33:49 +02:00
Harald Welte ac587f0825 Fix gsm_pchan2chan_nr() to use RSL_CHAN_OSMO_PDCH
When converting from GSM_PCHAN_PDCH, we should generate
a RSL channel number IE with the osmocom extension
RSL_CHAN_OSMO_PDCH rather than claiming it is a regular
TCH/F channel.

This is important as this function is used by
osmo-bts, too - and it decides which channel number IE is
put in the GSMTAP header for both GSMTAP tracing as well
as the GSMTAP based osmo-bts-virtual.

In order to avoid any unintended effect on libbsc,
we make sure to modify rsl_ipacc_pdch_activate() to
always use GSM_PCHAN_TCH_F in related RSL message.

Change-Id: Ie34219e64a6d89da4a79f2db8ec73d1909fb8280
2017-08-27 02:33:49 +02:00
Harald Welte 030e1973dd SGSN: Fix RAN information exposed on GTP during PDP CTX CREATE
In the PDP Context Create from SGSN to GGSN, we include information
about the RAN type (GERAN/UTRAN) and the Cell of the MS. This was
all hard-coded to GERAN, and wasn't updated when we added UTRAN
support to the SGSN.

Change-Id: I6c79e42c5e08b28fe8182555302a5505fbbaa313
2017-08-27 02:33:49 +02:00
Pau Espin babd38d8cf mgcp: Fix uplink activation of Osmux stream
Commit 5754206379 introduced
OSMUX_STATE_NEGOTIATING to fix a race condition present in osmo-bsc_nat.
However, after this change osmo-bsc_mgcp cannot switch to
OSMUX_STATE_ACTIVATING anymore, which means during osmux_send_dummy time
it won't call osmux_enable_endpoint(), which in turn won't set endp type
to MGCP_OSMUX_BSC.

If MGCP_OSMUX_BSC is not set, uplink streams are sent using regular RTP
instead of Osmux not matter it is enabled in config or not.

Change-Id: Ibcb59aa1ca25408f82cc88c2d5b81177b5f276dc
2017-08-27 02:33:49 +02:00
Ivan Kluchnikov 9f84139e86 handover_logic: set correct link to bts for subscriber_connection in case of moving this connection to another bts
In case of successful completion of handover gsm_subscriber_connection could be moved from one bts to another,
so connection link to bts should be replaced by link to bts, which owns new_lchan.
This bug was detected, because conn->bts->nr is used in call control log messages
and wrong number of bts was observed in these messages after handover.

Change-Id: Idc7dd412b7580c451e716b73ef7549826c60b0d9
2017-08-27 02:33:49 +02:00
Pau Espin e93fad8043 mgcp_osmux: Remove unused parameter
Change-Id: Icb1e7cb15fe04642578f5292124ebc1eac9c9aa3
2017-08-27 02:33:49 +02:00
Alexander Chemeris 3d18dda61a libcommon: Fix log output for bts>0.
Fixes regression probably introduced in c696cc28.

For bts>0 logging doesn't show bts number correctly when printing lchan
identification string - it will always show it as "bts=0". The reason for
this is that the identification string is cached before bts->nr value is
set to a proper value.

This patch sets bts->nr as part of the first step of the bts structure
initialization, before caching happens thus making sure the cached
identification string is cached with the correct values.

Change-Id: I61c18a7f021fcb1ec00d34a745f4e3ab03416c2d
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso d7e14da866 libmsc: use new smpp34 esm_class definitions
Replace magic numbers by esm_class definitions, which
have been added to latest libsmpp34 in Change-Id
I91afd8b462b8fd3b2c4c5b54f4eeb7ec5b730b65

Change-Id: I6c458690da60c8f3637680efbd718f6e8c6feb4c
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 9a3ed85bcb libmsc: use smpp34_tlv_for_each() to avoid suboptimal TLV handling
submit_to_sms() now handles two TLVs, so find_tlv() is suboptiomal and
it can be removed, since it would result in two passes on the TLV list.
Use new smpp34_tlv_for_each() helper to iterate over the list of TLVs
that is available since I446929feed049d0411e1629ca263e2bc41f714cc.

Change-Id: I53a65164a6cc4abc6bf57d9a8dc275cf21c90222
2017-08-27 02:33:49 +02:00
Pau Espin f113bcd671 libmsc: Remove comment not applying anymore
The change-id I7276d356d805a83ebeec72b02c8563b7135ea0b6 added msg_ref to
the databse but forgot to remove the comment stating it's not being
stored.

Change-Id: I204f098c8f2a480405446113e2181b2c53700cf3
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 4b50924fe8 libmsc: gsm340_gen_oa_sub() may return negative value
gsm340_gen_oa() returns a negative value if the output buffer that the
caller passes is too small, so we have to check the return value of this
function.

Fixes: CID 174178
Fixes: CID 174179
Change-Id: I47215d7d89771730a7f84efa8aeeb187a0911fdb
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 27aed14892 libmsc: support GSM 03.40 status report for nitb
This patch adds support for GSM 03.40 in nitb mode.

          MS         GSM 03.40          SMSC
           |                            |
           |         SMS-SUBMIT         |
           |--------------------------->|
           |     GSM 04.11 RP-ACK       |
           |<---------------------------|
           |         SMS-DELIVER        |
           |<---------------------------|
           |     GSM 04.11 RP-ACK       |
           |--------------------------->|
           |     SMS-STATUS-REPORT      |
           |<---------------------------|
           |     GSM 04.11 RP-ACK       |
           |--------------------------->|
           |                            |

Change-Id: I5cc7bb4ebadde0940f44d10c3df34707b0615160
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso bd71d32dca libmsc: handle delivery ack via SMPP SUBMIT SM / send GSM 03.40 status report
This patch adds gsm340_sms_send_status_report_tpdu() to build a
status-report. Moreover, set sms->report field if we see a SMPP
SUBMIT_SM with Delivery Acknowledgment esm_class, so this identifies
that this is a delivery report.

    MS        GSM 03.40           SMSC       SMPP 3.4               ESME
     |                             |                                |
     |                             |           SUBMIT-SM            |
     |                             |    esm_class = Delivery Ack    |
     |                             |<-------------------------------|
     |                             |         SUBMIT-SM-RESP         |
     |                             |------------------------------->|
     |                             |                                |
     |     SMS-STATUS-REPORT       |                                |
     |<----------------------------|                                |
     |     GSM 04.11 RP-ACK        |                                |
     |---------------------------->|                                |
     |                             |                                |

There is a FIXME message in this patch, that I just copied from
gsm340_gen_sms_deliver_tpdu() since TP-MMS is not supported by OpenBSC.

Change-Id: Ib70e534840308ed315f7add440351e649de3f907
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso eacb4007fb utils: smpp_mirror: bounce Delivery Receipts as Delivery Acknowledgments
Simple patch to test the new status-report support code, remove previous
code before Delivery Acknowledgement support was in place. Use
LOGL_DEBUG for logging messages here as suggested by Neels and Harald.

Change-Id: I877e228d8e174430f700631edbf9955972da7892
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 9891dae131 libmsc: update database to accomodate SMS status-report fields
SMPP DELIVER_SM messages with esm_class = Delivery Receipt need to send
this message reference (that the mobile phone allocates) to the ESME.
Thus, the ESME propagates it via SUBMIT_SM with esm_class = Delivery
Acknoledgment so that the SMSC sends the GSM 03.40 status-report to the
origin including this. Given this field is useful for status-reports, we
need to store it in the HLR database.

Moreover, we need a new field that specifies if the entry represents a
SMS status-report, to do the right handling from the gsm411_send_sms() -
such new handling comes in a follow up patch entitled "libmsc: handle
delivery ack via SMPP SUBMIT SM / send GSM 03.40 status report".

This patch includes the migration routines to the new database schema
revision 5, it's quite a bit of dbi boilerplate code - copied-pasted and
adapted.

Change-Id: I7276d356d805a83ebeec72b02c8563b7135ea0b6
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso adae859eeb libmsc: add support for SMPP delivery receipts
If the mobile phone requests a status report via SMS, send a DELIVER_SM
with esm_class = Delivery Receipt to ESME to indicate that the SMS has
been already delivered to its destination.

    MS        GSM 03.40           SMSC       SMPP 3.4               ESME
     |                             |                                |
     |       SMS-DELIVER           |                                |
     |<----------------------------|                                |
     |     GSM 04.11 RP-ACK        |                                |
     |---------------------------->|                                |
     |                             |           DELIVER-SM           |
     |                             |  esm_class = Delivery Receipt  |
     |                             |------------------------------->|
     |                             |         DELIVER-SM-RESP        |
     |                             |<-------------------------------|
     |                             |                                |

This patch implements "Appendix B. Delivery Receipt Format" as specified
in the SMPP 3.4 specs. This string is conveyed in the SMS message as
data, and it is only meaningful to the ESME, for logging purposes. The
"submit date" and "done date" are not yet set, and other fields are just
sent with dummy values, so they are left to be finished as future work.

The new SMPP TLV tag TLVID_user_message_reference is added to the SMPP
messages inconditionally now since this information is required by
delivery-reports to associate the status-report with the original SMS.

Change-Id: Ic1a9023074bfa938099377980b6aff9b262fab2a
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 59622b6220 utils: smpp_mirror: reflect message reference TLV
Useful to test the delivery receipt support. This TLV contains the
GSM03.40 message reference.

Change-Id: I1b0abaa7e06ffe1bd2242c70813d8b70e9fa954f
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 4f6a90f425 utils: smpp_mirror: temporarily munch SMPP delivery receipts
Just munch and log SMPP delivery receipts by now, don't mirror this, it
is going to break things in openbsc.

Follow up patch removes this and mirrors this SMPP message as a
SUBMIT_SM with esm_class = Delivery Acknowledgement.

Change-Id: I78e93bc4034679e238c8642ccf6a0e844b1d6d8b
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso e2681c5d97 utils: smpp_mirror: set registered_delivery field in SMPP SUBMIT_SM
To test delivery reports using this utility.

Change-Id: I0e477407531fdd4d906e53c9b5a48a79a239966f
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso db5ed3b9c6 libmsc: missing bit shift in status report flag when stored in sms object
So we just store 0 or 1 depending on what the mobile phone requests.

Change-Id: Idb7d5594219c0e458ccb561383a59604bc1a4201
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 791bdf70f2 libmsc: report status report request flag from SMPP SUBMIT_SM
Restore the sms status report request flag from SUBMIT_SM.

Change-Id: Iac05252253f8933a3875b4904599b7a225191a4b
2017-08-27 02:33:49 +02:00
Pablo Neira Ayuso 6ceac7c017 libmsc: set registered_delivery field in SMPP 3.4 DELIVER_SM messages
Propagate the status report request field to the SMPP message through
the registered_delivery field, so the ESME knows that the mobile phone
is asking for explicit delivery acknowledgment is required. See SMPP 3.4
specs section 5.2.17.

Change-Id: I59af60fa89cd10ae973c5e122789e3e03e3728ee
2017-08-27 02:33:49 +02:00
Neels Hofmeyr 41a5327178 timer vty: also print the default value in cmd doc
Rationale: allows seeing all timer defaults at once by doing

  OsmoBSC(config-net)# timer ?

Before, defaults are visible only by doing on each timer:

  OsmoBSC(config-net)# timer t1234 <tab>

Change-Id: I8259234e5c62e058dde56d531071440bbab11462
2017-08-27 02:33:49 +02:00
Neels Hofmeyr 5541e1d8d8 vty: add 'default' keyword to timer config
Change-Id: I4e837e8bedfad7ac4fd50048ecb016ddb37c2397
2017-08-27 02:33:49 +02:00
Neels Hofmeyr b0d623a984 cosmetic: vty for timers: remove obsolete range check
The VTY parsing already ensures the parameter range being 1..65535, no need to
check the range again.

Change-Id: I1cffa5b01cd5c589f1e42998e32135f1da8c960b
2017-08-27 02:33:48 +02:00
Pablo Neira Ayuso 3c14803b8d libmsc: move gsm340_rx_sms_submit() to sms_route_mt_sms()
Move the sms message-type-identifier (mti) handling away from the
routing logic. This patch allows us to reuse the sms_route_mt_sms()
function in a follow up patch for sms reports send through SMPP
DELIVER_SM with esm_class = Delivery Receipt whose Change-Id is
Ic1a9023074bfa938099377980b6aff9b262fab2a.

Change-Id: I3f3d30e0762b91e2099243b0be1a4b67cbb5e9c0
2017-08-27 02:33:48 +02:00
Pablo Neira Ayuso fdc9966a90 libmsc: remove 'deferred' parameter in sms_route_mt_sms()
No need to cache the sms object, just cache what we need into the
smpp_cmd structure. This simplifies what that I introduced in
93ffbd0029 ("libmsc: send RP-ACK to MS after ESME sends SMPP
DELIVER-SM-RESP").

Change-Id: Iba5f864f9bb963baff95969e306b1b7cff00c1e3
2017-08-27 02:33:48 +02:00
Pablo Neira Ayuso 26d3db8a32 libmsc: remove duplicate lines in deliver_to_esme()
This code is accidentally doing the same thing twice, remove it.

Change-Id: I68087a850399e22951d2407e4d8a09c671a775c9
2017-08-27 02:33:48 +02:00
Pablo Neira Ayuso 19e0536ad3 libmsc: remove dead code in sms_route_mt_sms()
The following branch:

	if (!rc && !gsms->receiver)
		rc = GSM411_RP_CAUSE_MO_NUM_UNASSIGNED;

at the end of sms_route_mt_sms() always evaluates false.

Just a bit before, in such function, we have this:

        if (!gsms->receiver) {
                ...
 #ifdef BUILD_SMPP
                ...
 #else
                ...
 #endif
                return rc;
        }

So, if there is no receiver, we just stop running code and return the RP
cause via the rc variable. Same applies to the smpp_first check under
the BUILD_SMPP ifdef (that I have removed in this snippet to keep this
commit message small).

Change-Id: Ic3502b5b169bc7a73a67fd6ff53d8b6c0dc045c8
2017-08-27 02:33:48 +02:00
Pablo Neira Ayuso f00d810e21 libmsc: do not leak pending SMPP command object on error path
Make sure the SMPP command object is released on errors.

Change-Id: I474584425d23fb379a9d71b33e29ac0e24f01e61
2017-08-27 02:33:48 +02:00
Pablo Neira Ayuso c0227194a3 gsm_04_11: get rid of unused parameter in sms_route_mt_sms()
This parameter is unused, remove it.

Change-Id: I797abce3f91447e8f397c7cf726db7425479fe0e
2017-08-27 02:33:48 +02:00
Holger Hans Peter Freyther 3730de4d87 sgsn: Convert cch_pdp to host order for libgtp
libgtp is calling gtpie_tv2 which will convert this uint16_t from host
to network order. So far libosmogsm and the sgsn treated the charging
characteristics as opaque data. So when moving from byte array to the
uint16_t do the swapping.

Change-Id: I977aec2e2f8d57802e45f591754e5733562d5c2a
2017-08-27 02:33:48 +02:00
Harald Welte 3b61a3812a remove code disabling T3109 if configured to 0
We no longer permit timers with a 0 value, so this case can never
happen.  Also, if it should happen, I'd rather have a timter expiring
immediately (and breaking something) than not being started in the
first place.

Change-Id: Ibfcdd3ddc0155caee89c501498329bde247621a0
2017-08-27 02:33:48 +02:00
Harald Welte 50546a9adb bsc_vty: Don't allow timers of zero (0)
It typically doesn't make sense to configure any of the GSM RR timer
to 0 (Seconds).  In fact, accidentially configuring any of the timers
to zero might have severe side effects, such as "stuck channels"
described in https://osmocom.org/issues/2380

Change-Id: I517828f2f0c80ec01cb63648db2626f17a67fe57
2017-08-27 02:33:48 +02:00
Harald Welte 5d1fa89819 GSM timers: User reasonable defaults; don't save if equal default
A number of the GSM timers (including T3109) had no reasonable
default values if not specified in the VTY / config file.  Together
with unconditional writing to the config file, this created
config files with a persistent setting for important timers as '0'.

To make things worse, many of our example cofig files suffered from the
same problem.

Let's avoid this from happening by
* having reasonable defaults if nothing specified in the config file
* conditionally savingg timers only if they differ from default
* reject any timer values that state zero during start-up (see previous
  commit)

Change-Id: Iaac0bfca423852b61d8b9eb1438157ef00d0d8c8
Closes: OS#2380
2017-08-27 02:33:48 +02:00
Harald Welte 1f7fe3c813 bsc_vty: Add VTY command to test CTRL TRAP feature
Using this new command (introduced in OsmoBSC + OsmoNITB), you can
simulate the generation of TRAP events for testin purposes.

start the control interface monitor as an example client program:
	./openbsc/contrib/bsc_control.py -m -d localhost -p 4249

then start OsmoBSC or OsmoNITB, telnet to the VTY and enter 'enable'
mode and issue the following (example) command:
	ctrl-interface generate-trap my.foo.var 2342

As a result, on the bsc_control.py you will see:
	Got message: TRAP 0 my.foo.var 2342

Change-Id: Ib1d2ec38290dc94797c1b365d9b733e5215ab7d1
2017-08-27 02:33:48 +02:00
Harald Welte 63dde0a44a gtphob: check for missing result of rate_ctr_group_alloc()
In case the counter group allocation fails, we must handle this
gracefully and fail the allocation of the parent object, too.

The recent change (Id I7dad4a4d52fe05f6b990359841b4408df5990e21) seems
to have missed one instance, so let's follow-up.

Change-Id: I1ee9e3d26dcc18e7f979fd9a786162cbcc50942c
Related: OS#2361
2017-08-27 02:33:48 +02:00
Harald Welte 852456db5f gsm_bts_trx_set_system_infos(): Disable non-existing SI
If we previously had a given SI present/active, we must send a
zero-length BCCH FILLING for that SI type to the BTS to stop it from
further transmitting this SI.

Change-Id: I33e356e2fa3a69efac9080813e3e9ef4e6438ed1
Closes: OS#2368
2017-08-27 02:33:48 +02:00
Harald Welte 942175ccd0 RSL: Allow disabling of BCCH/SACCH filling for given SI type
If we want to instruct the BTS to stop sending a given SI, we must be
able to send the respective BCCH INFO / SACCH FILLING with a header but
without any L3 data IE.  This patch enables the related functions to do
this whenever their data argument points to NULL.

Change-Id: I88b85614951a108574f05db3b706884afe7e87a9
2017-08-27 02:33:48 +02:00
Harald Welte 9b5ace86a1 Fix regression causing loss of static system-information messages
In commit 8b1a2f8cd7 we started to
initialize bts->si_valid to 0.  This means we are skipping the manually
configured static system information.

Instead, we have to initialize bts->si_valid to bts->si_mode_static,
i.e. start with those that are static and not to be auto-generated.

Found while developing
http://git.osmocom.org/osmo-ttcn3-hacks/tree/sysinfo

Change-Id: Iab9cc93cf6d54560a72cc393cc3721a8d10e04bf
Closes: #2367
2017-08-27 02:33:48 +02:00