NC | NSFS | Restrict path and new_bucket_path Values

[shirady]

Environment info

• NooBaa Version: master (current 5.17)
• Platform: NSFS NC (running in local machine with MacOS)

Actual behavior

(Originally it was with the title "Check Bucket Boundaries Fails Upload an Object")

1. When executing an S3 operation on a bucket - for example uploading an object we get an error that the upload failed.
   Note: the origin of the error as will be described below is in the check bucket boundaries - it is relevant for more operations (listing objects in a bucket, etc.).

Expected behavior

1. Not to have this error.

Steps to reproduce

1. Create an account using the cli: sudo node src/cmd/manage_nsfs account add --name <account-name> --new_buckets_path /tmp/nsfs_root1 --access_key <access-key> --secret_key <secret-key> --uid <uid> --gid <gid>.
   Note: Before creating the account need to give permission to the new_buckets_path: chmod 777 /tmp/nsfs_root1.
2. Start the NSFS server with: sudo node src/cmd/nsfs --debug 5
3. Use the account's details for the alias: alias s3-nc-user-1='AWS_ACCESS_KEY_ID=<access-key> AWS_SECRET_ACCESS_KEY=<secret-key> aws --no-verify-ssl --endpoint-url https://localhost:6443'.
4. Create the bucket: s3-nc-user-1 s3 mb s3://shira-1001-bucket-1.
5. Create and Upload an object: touch hello_world.txt and then s3-nc-user-1 s3 cp hello_world.txt s3://shira-1001-bucket-1, see the error:

upload failed: ./hello_world.txt to s3://shira-1001-bucket-1/hello_world.txt An error occurred (AccessDenied) when calling the PutObject operation: Access Denied

Note: after changing this line in the config: config.NSFS_CHECK_BUCKET_BOUNDARIES = false; // SDSD and restarting the server (ctrl + c and rerun sudo node src/cmd/nsfs --debug 5) we do not have an error:
s3-nc-user-1 s3 ls s3://shira-1001-bucket-1/
2024-07-02 13:32:07 0 hello_world.txt

More information - Screenshots / Logs / Other output

Logs from the server:

Jul-2 13:13:50.988 [nsfs/17208]    [L1] core.sdk.namespace_fs:: check_bucket_boundaries: fs_context { uid: 1001, gid: 1001, new_buckets_path: '/tmp/nsfs_root1', warn_threshold_ms: 100, backend: '', report_fs_stats: [Function (anonymous)] } file_path /tmp/nsfs_root1/shira-1001-bucket-1 this.bucket_path /tmp/nsfs_root1/shira-1001-bucket-1
2024-07-02 13:13:50.988168 [PID-17208/TID-259] [L1] FS::FSWorker::Begin: RealPath _path=/tmp/nsfs_root1/shira-1001-bucket-1
2024-07-02 13:13:50.988192 [PID-17208/TID-8707] [L1] FS::FSWorker::Execute: RealPath _path=/tmp/nsfs_root1/shira-1001-bucket-1 _uid=1001 _gid=1001 _backend=
2024-07-02 13:13:50.988212 [PID-17208/TID-8707] [L1] FS::FSWorker::Execute: RealPath _path=/tmp/nsfs_root1/shira-1001-bucket-1 _uid=1001 _gid=1001 geteuid()=1001 getegid()=1001 getuid()=1001 getgid()=1001
2024-07-02 13:13:50.988263 [PID-17208/TID-8707] [L1] FS::FSWorker::Execute: RealPath _path=/tmp/nsfs_root1/shira-1001-bucket-1  took: 0.018041 ms
2024-07-02 13:13:50.988284 [PID-17208/TID-259] [L1] FS::RealPath::OnOK: _path=/tmp/nsfs_root1/shira-1001-bucket-1 _full_path=/private/tmp/nsfs_root1/shira-1001-bucket-1
Jul-2 13:13:50.988 [nsfs/17208]    [L0] core.sdk.namespace_fs:: check_bucket_boundaries: the path /tmp/nsfs_root1/shira-1001-bucket-1 is not in the bucket /tmp/nsfs_root1/shira-1001-bucket-1 boundaries
Jul-2 13:13:50.990 [nsfs/17208]  [WARN] core.sdk.namespace_fs:: NamespaceFS: upload_object buffer pool cleanup error Error: Entry /tmp/nsfs_root1/shira-1001-bucket-1/hello_world.txt is not in bucket boundaries
    at Object.new_error_code (/Users/shiradymnik/SourceCode/noobaa-core/src/util/error_utils.js:16:26)
    at NamespaceFS._check_path_in_bucket_boundaries (/Users/shiradymnik/SourceCode/noobaa-core/src/sdk/namespace_fs.js:2541:31)
    at async NamespaceFS.upload_object (/Users/shiradymnik/SourceCode/noobaa-core/src/sdk/namespace_fs.js:1126:13)
    at async NsfsObjectSDK._call_op_and_update_stats (/Users/shiradymnik/SourceCode/noobaa-core/src/sdk/object_sdk.js:543:27)
    at async Object.put_object [as handler] (/Users/shiradymnik/SourceCode/noobaa-core/src/endpoint/s3/ops/s3_put_object.js:39:19)
    at async handle_request (/Users/shiradymnik/SourceCode/noobaa-core/src/endpoint/s3/s3_rest.js:150:19)
    at async Object.s3_rest [as handler] (/Users/shiradymnik/SourceCode/noobaa-core/src/endpoint/s3/s3_rest.js:65:9) {
  code: 'EACCES'
}
Jul-2 13:13:50.991 [nsfs/17208] [ERROR] core.endpoint.s3.s3_rest:: S3 ERROR <?xml version="1.0" encoding="UTF-8"?><Error><Code>AccessDenied</Code><Message>Access Denied</Message><Resource>/shira-1001-bucket-1/hello_world.txt</Resource><RequestId>ly494dmt-6yxcl2-f9x</RequestId></Error> PUT /shira-1001-bucket-1/hello_world.txt {"host":"localhost:6443","accept-encoding":"identity","content-type":"text/plain","user-agent":"aws-cli/2.15.36 Python/3.11.9 Darwin/23.4.0 source/arm64 prompt/off command/s3.cp","content-md5":"1B2M2Y8AsgTpgAmY7PhCfg==","expect":"100-continue","x-amz-date":"20240702T101350Z","x-amz-content-sha256":"UNSIGNED-PAYLOAD","authorization":"AWS4-HMAC-SHA256 Credential=Dwertyuiopasdfg11001/20240702/us-east-1/s3/aws4_request, SignedHeaders=content-md5;content-type;host;x-amz-content-sha256;x-amz-date, Signature=60bd00111e1602ed42773d4b464c5e580886ce1e3f92af472368a88b85d7886b","content-length":"0"} Error: Entry /tmp/nsfs_root1/shira-1001-bucket-1/hello_world.txt is not in bucket boundaries
    at Object.new_error_code (/Users/shiradymnik/SourceCode/noobaa-core/src/util/error_utils.js:16:26)
    at NamespaceFS._check_path_in_bucket_boundaries (/Users/shiradymnik/SourceCode/noobaa-core/src/sdk/namespace_fs.js:2541:31)
    at async NamespaceFS.upload_object (/Users/shiradymnik/SourceCode/noobaa-core/src/sdk/namespace_fs.js:1126:13)
    at async NsfsObjectSDK._call_op_and_update_stats (/Users/shiradymnik/SourceCode/noobaa-core/src/sdk/object_sdk.js:543:27)
    at async Object.put_object [as handler] (/Users/shiradymnik/SourceCode/noobaa-core/src/endpoint/s3/ops/s3_put_object.js:39:19)
    at async handle_request (/Users/shiradymnik/SourceCode/noobaa-core/src/endpoint/s3/s3_rest.js:150:19)
    at async Object.s3_rest [as handler] (/Users/shiradymnik/SourceCode/noobaa-core/src/endpoint/s3/s3_rest.js:65:9)

[romayalon]

@shirady This only happens because you use /tmp/ and not /private/tmp/ as the bucket path on your Mac.
/tmp/ on Mac is a symlink to /private/tmp/ and when checking the boundaries we check the real path of the object /private/tmp/shira-1001-bucket-1/hello_world.txt is in the boundaries of the bucket path which is /tmp/shira-1001-bucket-1. If we do want to support bucket path as symlink it's a very small fix, @guymguym do you see a reason for not allowing bucket path to be a symlink?

[guymguym]

@romayalon @shirady Same reason as we protect it for things inside a bucket - to avoid exposing sensitive data from the system. For example what if someone managed to set the bucket path to ln -s /etc /fs/bucketpath and then tried to download passwd, or worse - upload it... This config option is meant to prevent that by default. If you want to allow it for your dev env, override the config.

[shirady]

@guymguym, I don't understand what is the exact difference if this link is a symlink or an absolute path in which we protect it?

Currently, as I understand it what blocks a new_buckets_path is the check of in the CLI is_dir_rw_accessible and this dir will not be accessible to a user that is not uid and gid 0 (root) - which means that your concern of exposing sensitive data can happen if someone passes to the CLI, for example: sudo node src/cmd/manage_nsfs account add --name shira-path --new_buckets_path /etc/noobaa.conf.d --uid 0 --gid 0 (I took our config path as an example of a directory in /etc)

output (omitting details of access_key, secret_key and master_key_id):

{
  "response": {
    "code": "AccountCreated",
    "reply": {
      "_id": "6683f6f16a973327fcf08dfc",
      "name": "shira-path",
      "email": "shira-path",
      "creation_date": "2024-07-02T12:47:45.608Z",
      "access_keys": [
        {
          "access_key": "",
          "secret_key": ""
        }
      ],
      "nsfs_account_config": {
        "uid": 0,
        "gid": 0,
        "new_buckets_path": "/etc/noobaa.conf.d"
      },
      "allow_bucket_creation": true,
      "master_key_id": ""
    }
  }
}

[shirady]

I changed the title of the issue to match what I wrote in the commented above, and so we will define it and solve it.