Commit graph

195 commits

Author SHA1 Message Date
Leonard Lyubich
b48a4ede02 [#125] services/eacl: Use latest object header keys
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-29 19:25:54 +03:00
Leonard Lyubich
8d931b81a6 [#125] object/search: Use latest search filter keys
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-29 19:25:54 +03:00
Leonard Lyubich
f34ad9e730 [#125] services/eacl: Fix undefined method usage
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-29 19:25:54 +03:00
Alex Vanin
d08c1c76c1 [#122] Reduce precision from balance contract to Fixed8.
Fixed8 won't overflow int64 for values less than 92 billion
that is suitable for GAS.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-29 10:14:59 +03:00
Leonard Lyubich
f66c7958e7 [#109] services/policer: Assign tasks to Replicator
Make Policer to call AddTask method of Replicator when an insufficient
number of copies of an object is detected in the container.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 15:23:22 +03:00
Leonard Lyubich
2d46baa4a5 [#109] services: Implement Replicator service
Implement Replicator service that performs background work to replicate
local object to remote nodes in the container. Replicator is going to be
used by Policer.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 15:23:22 +03:00
Leonard Lyubich
53efa18e14 [#109] object/put: Implement remote object sender
Define RemoteSender structure with PutObject method that puts object to a
remote node locally.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 15:23:22 +03:00
Leonard Lyubich
968033deed [#40] object/put: Assign zero return of MaxObjectSize invalid
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 14:03:25 +03:00
Leonard Lyubich
7fdb14cf8a [#83] services/response: Set epoch number from network state
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 10:54:48 +03:00
Leonard Lyubich
19f9c7eacb [#83] services: Remove setting of meta header from executing services
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 10:54:48 +03:00
Leonard Lyubich
0341773318 [#83] services: Implement response sub-service for each service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 10:54:48 +03:00
Leonard Lyubich
6bede7d836 [#83] services/util: Implement response service
Create response package. Implement response Service that sets values of
response meta header.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 10:54:48 +03:00
Leonard Lyubich
1cc7983c4e [#83] services/util: Add meta header methods to ResponseMessage
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 10:54:48 +03:00
Leonard Lyubich
71a06f9e01 [#83] services/util: Define type of response message interface
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-23 10:54:48 +03:00
Alex Vanin
7464254680 [#106] Put simplest bearer token check first
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-22 18:02:11 +03:00
Alex Vanin
23ec33e821 [#106] Check bearer token lifetime
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-22 18:02:11 +03:00
Alex Vanin
bb455af05f [#106] Ignore bearer token if basic ACL restrict it
There is a bit to allow or deny bearer token check for
each object service method. If this bit is not set then
ignore bearer token and use extended ACL table from
sidechain.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-22 18:02:11 +03:00
Alex Vanin
89cd2ad463 [#106] Process bearer token in ACL service
If bearer token is presented in the request then check
if it is a valid one and then use it to process extended
ACL checks.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-22 18:02:11 +03:00
Alex Vanin
094248690b [#115] Make ACL classifier errors transparent for client
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-22 11:55:28 +03:00
Alex Vanin
ca552f53c6 [#115] Check session token validity
Malicious user can stole public session key and use
it by sending request from it's own scope. To prevent
this each session token is signed and signature private
key must be corresponded with owner id in token. Therefore
malicious node cannot impersonate request without private
key to sign token.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-22 11:55:28 +03:00
Leonard Lyubich
16a5107ef1 [#60] object/put: Provide network State interface to formatter
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-22 11:54:08 +03:00
Leonard Lyubich
b627814dd8 [#60] object/transformer: Set creation epoch number in new objects
Set value of CreationEpoch object field to the value from network State.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-22 11:54:08 +03:00
Leonard Lyubich
4a56f82571 [#60] object/transformer: Group parameters of NewFormatTarget func
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-22 11:54:08 +03:00
Leonard Lyubich
2541ed4b8f [#88] object/eacl: Use String() methods to calculate ID values
Replace hex encoding of IDs with String() call (base58) in eACL processing.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-21 18:53:04 +03:00
Leonard Lyubich
5318abcf38 [#88] object/search: Use String() methods to calculate ID values
Replace hex encoding of IDs with String() call (base58) in search query
processing.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-21 18:53:04 +03:00
Leonard Lyubich
0dab4b7581 [#108] services: Implement Policer service
Implement Policer service that performs background work to check compliance
with the placement policy for local objects in the container. In the initial
implementation, the selection of the working queue of objects is
simplified, and there is no transfer of the result to the replicator.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-21 14:42:51 +03:00
Leonard Lyubich
f6e56aa956 [#108] placement: Implement Builder from netmap source
Implement placement.Builder interface on netmap.Source wrapper.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-21 14:42:51 +03:00
Leonard Lyubich
5017ff0e4a [#108] object/head: Export remote header retrieval utility
Export remote head functionality in headsvc package. Refactor head service
to use RemoteHeader.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-21 14:42:51 +03:00
Leonard Lyubich
5ad0df7794 [#108] object/head: Return 404 error if header was not found
Define ErrNotFound error in headsvc package. Return ErrNotFound from Head
method if the header was not found in the container.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-21 14:42:51 +03:00
Alex Vanin
ae0dd9e051 [#106] Pass bearer token through generated requests
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-20 18:05:29 +03:00
Alex Vanin
9e08b41a6f [#102] Set split header in left object
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-20 09:59:09 +03:00
Alex Vanin
719075ca97 [#99] Fix no-root search matcher
Wrong boolean operation order made matcher return false
on `non-root` search query with non-regular objects. Instead
it should return true for `non-root` query and false for `root`
query.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-16 13:45:35 +03:00
Alex Vanin
1332a6d3a8 [#92] Provide session token to all produced requests
If object service produces new request, the should contain
session token. This is the only way for node to grant access
for a private container.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-15 10:20:10 +03:00
Alex Vanin
2d5cb378a7 [#84] Add netmap service executor and signer
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-09 09:15:18 +03:00
Alex Vanin
0e7e0bd2d6 [#84] Remove mocks and debug code from neofs-node services
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-09 09:15:18 +03:00
Alex Vanin
87fc4f5df7 [#82] Use morph wrapper in container service
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-08 11:22:50 +03:00
Alex Vanin
cd34145969 [#73] Use request owner public key in eACL check
Classifier fetches public key of the request owner
and owner itself. Extended ACL check should rely on
this public key, because it might be extracted from
session token.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-05 18:02:37 +03:00
Alex Vanin
7a2654719e [#71] Return only regular objects in root object search
Root search applies for user objects, so it should not
return tombstones and storage groups.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-05 14:03:55 +03:00
Alex Vanin
11262bed4a [#71] Broadcast tombstone to container
With one tombstone for split objects we can't simply
place it in container. We should inform all nodes that
store split objects of removed original object.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-05 14:03:55 +03:00
Leonard Lyubich
9cdf7d3896 [#69] object/acl: Check eACL rules in ACL service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 14:02:14 +03:00
Leonard Lyubich
1d676fcfb2 [#69] object/acl: Add eACL components to service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 14:02:14 +03:00
Leonard Lyubich
a7782cf1f9 [#69] object/acl: Extended requestInfo structure
Add container identifier field. Add send public key field.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 14:02:14 +03:00
Leonard Lyubich
6c3c872ee4 [#69] object/acl: Define access denied error
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 14:02:14 +03:00
Leonard Lyubich
0f52444ae9 [#69] object/acl: Change basic ACL type in requestInfo
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 14:02:14 +03:00
Leonard Lyubich
30e6912c7b [#69] object/acl: Construct service from options
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 14:02:14 +03:00
Leonard Lyubich
e5898c9ca8 [#69] object/acl: Rename BasicChecker to Service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 14:02:14 +03:00
Leonard Lyubich
0d5495e997 [#70] object manager: Implement an example object garbage collector
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 09:36:29 +03:00
Leonard Lyubich
798fca9354 [#70] core/object: Process a delete group at tombstone
Send object group to delete queue processor after tombstone content
validation.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 09:36:29 +03:00
Leonard Lyubich
2b16edebc9 [#70] object/put: Fix NPE caused by nil FormatValidator
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-05 09:36:29 +03:00
Alex Vanin
801999c577 [#66] Impersonate object service verb from session token
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 19:47:49 +03:00
Alex Vanin
afeebd310c [#66] Use session token of object header at put ACL check
Owner of the request is stored in session token most of the times.
Put request contains session token in the object body, so we have
to fetch it from there.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 19:47:49 +03:00
Leonard Lyubich
69a69cdbee [#67] object/eacl: Implement eACL validator
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 19:46:45 +03:00
Leonard Lyubich
44fcd2f212 [#64] object/delete: Change the formation of tombstone
Make delete service to write list of child object addresses to tombstone
payload.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 19:46:27 +03:00
Alex Vanin
861bac3892 [#59] Use max msg size in transport server and splitter
For GRPC it is about 4 MiB.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
d2009c8731 [#59] Add grpc payload splitter in object service chain
GRPC has default message limit of 4MiB. Since every transmitted
neofs message has to be signed, then original message should
be split into transfer fit structures before signature service.

This commit introduce transport payload splitter for object
service pipeline. This splitter works with stream response
for methods:

  - object.Get
  - object.Range
  - object.Search

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
64691e6248 [#62] object/transformer: Fix incorrect relation init stage
In previous implementation InitRelations call in payload size limiter was
called in write chunk method. This provoked clearing the split header in
children starting from the second.

Replace InitRelations call to the 1st child allocating stage.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
e158497560 [#43] cmd/neofs-node: Support hostnames with dns, ipv4 and ipv6 addresses
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
f930993e3a [#43] pkg/network: Do not panic at multiaddr to net.Addr conversion
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
6824a6f67b [#61] object/search: Support non-root and non-leaf filters
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
51e373c3f0 [#61] object/search: Support latest search filters
Refactor query to match object and its parents in a single call. Support
KeyRoot and KeyLeaf filters.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
f89c848e84 [#61] object/search: Filter objects by container ID from request
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
1654df4d97 [#61] Update to latest neofs-api-go changes
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
f251645def [#58] object/delete: Process linking object in Delete service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
16252ad09a [#58] object/search: Add object-with-children filter
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
624e8cd3cb [#58] object/search: Refactor RelationSearcher implementation
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
4bcfed37ca [#58] object/head: Generalize RelationSearcher interface method
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
6eb353c804 [#58] object/put: Validate payload content after filling
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
017afbf0e3 [#58] services/object: Implement Delete service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
b24adeae89 [#58] object/transformer: Inherit type of parent object
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
39ddb3a3f4 [#45] object/search: Fix double write of local result
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
08b9ae547a [#45] object/search: Add filtering parent objects
In previous implementation object.Search services allowed to search only
physically stored objects. This limitation did not allow getting the ID of
the split object.

Extend search execution logic with parent object filtering. Parent objects
that passed filters are now included in the result

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
88459963fb [#57] services/object: Sign requests with session key
Use key storage in object services in order to sign requests with private
session key within user session.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
be322835af [#57] services/object: Implement private key storage
Implement storage that provides access to local node key and session keys
through session token.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
2da323c4b9 [#57] services/object: Add session token to common parameters
Add session token field to CommonPrm. Remove session token field from Put
parameters.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
39c17253be [#57] services/object: Combine common service parameters
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
8cddbe58a6 [#56] object/transformer: Write session token to object body
Add session token argument to object formatter constructor which is written
to the object. Pass session token from trusted object Put.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
a4b9560ef6 [#56] object/put: Validate object format in untrusted Put
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
12d57af998 [#56] Update to latest neofs-api-go changes
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
fc74e9b40c [#32] Remove recover from basic ACL checks
Basic ACL checker gets request field via getters that are
NPE-free, therefore we don't need to worry about function
invocations on nil structures.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
4a8de3263d [#32] Use less v2 specific structures in basic ACL checker
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
c5a44e0a05 [#32] Add tests for basic ACL helper
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
91fef72bb6 [#32] Make basic ACL check in all object request
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
49ee9a14a1 [#32] Add basic ACL helper
Basic ACL helper provides functions for simple access to
bit fields of basic ACL.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
f6904db84f [#32] Use pkg/core interfaces to fetch container and netmap
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
ad36a2cd8f [#32] Use classifier in basic ACL check
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
5045b0c3d4 [#32] Add request sender classifier
ACL has to classify request senders by roles:
- owner of the container,
- request from container or inner ring node,
- any other request.

According to this roles ACL checker use different
bits of basic ACL to grant or deny access.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Alex Vanin
ab565b1862 [#32] Add basis of basic ACL check service
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
1b5ac0f2ae [#55] object/transformer: Fix NPE in case of empty payload
In previous implementation payload size limiter panicked in case of payload
emptiness. It was caused by the component waiting for at least one write of
a part of the payload.

Fix NPE occurrence with internal initialization after the WriteHeader call.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
867f1d772d [#53] Revert "[#51] object/put: Fix incorrect splited object streaming"
Revert commit 803ea345 that which spawned a duplication of the payload of
objects.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
0a51263e72 [#53] services/object: Implement GetRangeHash service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
834a8597c5 [#53] object/util: Add seek range function to range traverser
Add SetSeekRange method to RangeTraverser that switches traverser to work
with provided object payload range.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
8791c4f0a5 [#53] object/range: Share object range traverser between services
Replace object range chain utilities to object/util package in order to
reuse it in other services.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
759605410a [#53] object/range: Do not add chain element without the need
In previous implementation one excess element could be added to the chain.
Add previous sibling presence check to prevent this.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
bf2c33d7a9 [#52] services/object: Implement Get service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
3880315a3f [#52] object/range: Add full range option to parameters
Add FullRange option to get range operation parameters that allows to get
payload range [0:object_size] w/o the actual knowledge of the object size.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
abf9ad3573 [#52] object/range: Attach received object header to result
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
0490107165 [#50] services/object: Implement GetRange service
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
dd16f568c3 [#50] object/head: Add right child to Head operation result
Head service receives right child of the processing object in some cases.
Add right child to Head result in order to use it as needed.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
3692f708ca [#51] object/put: Fix incorrect splited object streaming
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00
Leonard Lyubich
6f4b477195 [#44] services/object: Refactor for minor optimization
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-10-02 11:25:36 +03:00