NeoFS S3 Gateway

NeoFS S3 gateway provides API compatible with Amazon S3 cloud storage service.

Installation

go get -u github.com/nspcc-dev/neofs-s3-gw

Or you can call make to build it from the cloned repository (the binary will end up in bin/neofs-s3-gw with authmate helper in bin/neofs-authmate).

Notable make targets:

dep          Check and ensure dependencies
image        Build clean docker image
dirty-image  Build dirty docker image with host-built binaries
format       Run all code formatters
lint         Run linters
version      Show current version

Or you can also use a Docker image provided for released (and occasionally unreleased) versions of gateway (:latest points to the latest stable release).

Execution

Minimalistic S3 gateway setup needs:

• NeoFS node(s) address (S3 gateway itself is not a NeoFS node) Passed via -p parameter or via S3_GW_PEERS_<N>_ADDRESS and S3_GW_PEERS_<N>_WEIGHT environment variables (gateway supports multiple NeoFS nodes with weighted load balancing).
• a key used to communicate with NeoFS nodes Passed via --neofs-key parameter or S3_GW_NEOFS-KEY environment variable.
• a key used for client authentication Passed via --auth-key parameter or S3_GW_AUTH-KEY environment variable. To generate it use neofs-authmate generate-keys command.

These two commands are functionally equivalent, they run the gate with one backend node, some keys and otherwise default settings:

$ neofs-s3-gw -p 192.168.130.72:8080 --neofs-key KxDgvEKzgSBPPfuVfw67oPQBSjidEiqTHURKSDL1R7yGaGYAeYnr \
  --auth-key a04edd5b3c497eed83be25fb136bafd056928c17986440745775223615f2cbab

$ S3_GW_PEERS_0_ADDRESS=192.168.130.72:8080 \
  S3_GW_NEOFS-KEY=KxDgvEKzgSBPPfuVfw67oPQBSjidEiqTHURKSDL1R7yGaGYAeYnr \
  S3_GW_AUTH-KEY=a04edd5b3c497eed83be25fb136bafd056928c17986440745775223615f2cbab \
  neofs-s3-gw

Configuration

In general, everything available as CLI parameter can also be specified via environment variables, so they're not specifically mentioned in most cases (see --help also).

Nodes and weights

You can specify multiple -p options to add more NeoFS nodes, this will make gateway spread requests equally among them (using weight 1 for every node):

$ neofs-s3-gw -p 192.168.130.72:8080 -p 192.168.130.71:8080

If you want some specific load distribution proportions, use weights, but they can only be specified via environment variables:

$ HTTP_GW_PEERS_0_ADDRESS=192.168.130.72:8080 HTTP_GW_PEERS_0_WEIGHT=9 \
  HTTP_GW_PEERS_1_ADDRESS=192.168.130.71:8080 HTTP_GW_PEERS_1_WEIGHT=1 neofs-s3-gw

This command will make gateway use 192.168.130.72 for 90% of requests and 192.168.130.71 for remaining 10%.

Keys

NeoFS (--neofs-key) and authentication (--auth-key) keys are mandatory parameters. NeoFS key can be a path to private key file (as raw bytes), a hex string or (unencrypted) WIF string. Authentication key is either a path to raw private key file or a hex string.

Binding and TLS

Gateway binds to 0.0.0.0:8080 by default and you can change that with --listen_address option.

It can also provide TLS interface for its users, just specify paths to key and certificate files via --tls.key_file and --tls.cert_file parameters. Note that using these options makes gateway TLS-only, if you need to serve both TLS and plain text you either have to run two gateway instances or use some external redirecting solution.

Example to bind to 192.168.130.130:443 and serve TLS there (keys and nodes omitted):

$ neofs-s3-gw --listen_address 192.168.130.130:443 \
  --tls.key_file=key.pem --tls.cert_file=cert.pem

Monitoring and metrics

Pprof and Prometheus are integrated into the gateway, but not enabled by default. To enable them use --pprof and --metrics flags or HTTP_GW_PPROF/HTTP_GW_METRICS environment variables.

S3 API supported

Reference:

• AWS S3 API Reference

Bucket/Object-Level Actions

#	Method Name	Status
1	AbortMultipartUpload	Unsupported
2	CompleteMultipartUpload	Unsupported
3	CopyObject	Supported
4	CopyObjectPart	Unsupported
5	DeleteBucket	Unsupported
6	DeleteBucketEncryption	Unsupported
7	DeleteBucketLifecycle	Unsupported
8	DeleteBucketPolicy	Unsupported
9	DeleteBucketTagging	Unsupported
10	DeleteBucketWebsite	Unsupported
11	DeleteMultipleObjects	Supported
12	DeleteObject	Supported
13	DeleteObjectTagging	Unsupported
14	GetBucketACL	Unsupported
15	GetBucketAccelerate	Supported
16	GetBucketCors	Unsupported
17	GetBucketEncryption	Unsupported
18	GetBucketLifecycle	Unsupported
19	GetBucketLocation	Unsupported
20	GetBucketLogging	Unsupported
21	GetBucketNotification	Unsupported
22	GetBucketObjectLockConfig	Unsupported
23	GetBucketPolicy	Unsupported
24	GetBucketReplication	Unsupported
25	GetBucketRequestPayment	Unsupported
26	GetBucketTagging	Unsupported
27	GetBucketVersioning	Unsupported
28	GetBucketWebsite	Unsupported
29	GetObject	Supported
30	GetObjectACL	Unsupported
31	GetObjectLegalHold	Unsupported
32	GetObjectRetention	Unsupported
33	HeadBucket	Supported
34	HeadObject	Supported
35	ListBucketObjectVersions	Unsupported
36	ListBuckets	Supported
37	ListMultipartUploads	Unsupported
38	ListObjectParts	Unsupported
39	ListObjectsV1	Supported
40	ListObjectsV2	Supported
41	ListenBucketNotification	Unsupported
42	NewMultipartUpload	Unsupported
43	PostPolicyBucket	Unsupported
44	PutBucket	Unsupported
45	PutBucketACL	Unsupported
46	PutBucketEncryption	Unsupported
47	PutBucketLifecycle	Unsupported
48	PutBucketNotification	Unsupported
49	PutBucketObjectLockConfig	Unsupported
50	PutBucketPolicy	Unsupported
51	PutBucketTagging	Unsupported
52	PutBucketVersioning	Unsupported
53	PutObject	Supported
54	PutObjectACL	Unsupported
55	PutObjectLegalHold	Unsupported
56	PutObjectPart	Unsupported
57	PutObjectRetention	Unsupported
58	PutObjectTagging	Unsupported
59	SelectObjectContent	Unsupported

NeoFS AuthMate

Authmate is a tool to create gateway key pairs and AWS credentials. AWS users are authenticated with access key IDs and secrets, while NeoFS users are authenticated with key pairs. To complicate things further we have S3 gateway that usually acts on behalf of some user, but user doesn't necessarily want to give his keys to the gateway.

To solve this we use NeoFS bearer tokens that are signed by the owner (NeoFS "user") and that can implement any kind of policy for NeoFS requests allowed using this token. But tokens can't be used directly as AWS credentials, thus they're stored on NeoFS as regular objects and access key ID is just an address of this object while secret is an SHA256 hash of this key.

Tokens are not stored on NeoFS in plaintext, they're encrypted with a set of gateway keys. So in order for gateway to be able to successfully extract bearer token the object needs to be stored in a container available for the gateway to read and it needs to be encrypted with this gateway's key (among others potentially).

Generation of key pairs

To generate key pairs for gateways, run the following command (--count is 1 by default):

$ ./neofs-authmate generate-keys --count=2

[
  {
    "private_key": "b8ba980eb70b959be99915d2e0ad377809984ccd1dac0a6551907f81c2b33d21",
    "public_key": "dd34f6dce9a4ce0990869ec6bd33a40e102a5798881cfe61d03a5659ceee1a64"
  },
  {
    "private_key": "407c351b17446ca07521faceb8b7d3e738319635f39f892419e2bf94462b4419",
    "public_key": "20453af9d7f245ff6fdfb1260eaa411ae3be9c519a2a9bf1c98233522cbd0156"
  }
]

Private key is the one to use for neofs-s3-gw command, public one can be used to create new AWS credentials.

Issuance of a secret

To issue a secret means to create a Bearer token and put it as an object into container on the NeoFS network. The token is encrypted by a set of gateway keys, so you need to pass them as well.

If a parameter container-id is not set, a new container will be created.

If a parameter rules is not set, it will be auto-generated with values:

{
    "version": {
        "major": 2,
        "minor": 6
    },
    "containerID": {
        "value": "%CID"
    },
    "records": [
        {
            "operation": "GET",
            "action": "ALLOW",
            "filters": [],
            "targets": [
                {
                    "role": "OTHERS",
                    "keys": []
                }
            ]
        }
    ]
}

Example of a command to issue a secret with custom rules for multiple gates:

$ ./neofs-authmate issue-secret --neofs-key user.key \
--peer 192.168.130.71:8080 \ 
--rules '{"records":[{"operation":"PUT","action":"ALLOW","filters":[],"targets":[{"role":"OTHERS","keys":[]}]}]}' \ 
--gate-public-key dd34f6dce9a4ce0990869ec6bd33a40e102a5798881cfe61d03a5659ceee1a64 \
--gate-public-key 20453af9d7f245ff6fdfb1260eaa411ae3be9c519a2a9bf1c98233522cbd0156

{
  "access_key_id": "5g933dyLEkXbbAspouhPPTiyLZRg4axBW1axSPD87eVT_AiXsH4AjYy1iTJ4C1WExzjBrSobJsQFWEyKLREe5sQYM",
  "secret_access_key": "438bbd8243060e1e1c9dd4821756914a6e872ce29bf203b68f81b140ac91231c",
  "owner_private_key": "274fdd6e71fc6a6b8fe77bec500254115d66d6d17347d7db0880d2eb80afc72a"
}

Access key ID and secret access key are AWS credentials that you can use with any S3 client.

Obtainment of a secret access key

You can get a secret access key associated with access key ID by obtaining a secret stored on the NeoFS network:

$ ./neofs-authmate obtain-secret --neofs-key user.key \
--peer 192.168.130.71:8080 \
--gate-private-key b8ba980eb70b959be99915d2e0ad377809984ccd1dac0a6551907f81c2b33d21 \
--access-key-id 5g933dyLEkXbbAspouhPPTiyLZRg4axBW1axSPD87eVT_AiXsH4AjYy1iTJ4C1WExzjBrSobJsQFWEyKLREe5sQYM

{
 "secret_access_key": "438bbd8243060e1e1c9dd4821756914a6e872ce29bf203b68f81b140ac91231c"
}