Overview

Since SeaweedFS is a distributed system with many volume servers, the volume servers have the risk of being changed without proper access control. We want to have the freedom to place a volume server anywhere we want, with the confidence that nobody can tamper the data.

We will address the volume servers first. The following items are not covered, yet:

  • master server http REST services
  • filer server http REST servicesIn summary, here are what can be achieved.
ServerServiceNote
mastergRPCsecured by mutual TLS
volumegRPCsecured by mutual TLS
filergRPCsecured by mutual TLS
masterhttp"weed master -disableHttp", disable http operations, only gRPC operations are allowed.
filerhttp"weed filer -disableHttp", disable http operations, only gRPC operations are allowed. This works with "weed mount" by FUSE.
volumehttp writeset jwt.signing.key in security.toml in master and volume servers to check token for write operations
volumehttp readunprotected, but url is not guessable

Generate security.toml file

See Security Configuration

Servers in SeaweedFS usually support 2 kinds of operations: gRPC and REST.

Securing gRPC operations

The following operations are implemented via gRPC.

  • requests from filer to master
  • requests from master to volume servers
  • delete operations from filer or other clients (mount, s3, filer.copy, filer.replicate, etc) to volume servers
  • requests from clients to filer

All gRPC operations can optionally be secured via mutual TLS, by customizing the security.toml file. See Security Configuration.

Securing Volume Servers

Besides gRPC mentioned above, volume servers can only be changed by file upload, update, and delete operations. Json Web Token (JWT) is used to authorize access for each file id.

JWT-based access control

To enable JWT-based access control,

  • generate security.toml file by weed scaffold -config=security
  • set jwt.signing.key to a secrete string
  • copy the same security.toml file to the masters and all volume servers.

How JWT-based access control works

  • To upload a new file, when requesting a new fileId via http://<master>:<port>/dir/assign, the master will use the jwt.signing.key to generate and sign a JWT, and set it to response header Authorization. The JWT is valid for 10 seconds.
  • To update or delete a file by fileId, the JWT can be read from the response header Authorization of http://<master>:<port>/dir/lookup?fileId=xxxxx.
  • When sending upload/update/delete HTTP operations to a volume server, the reqeust header Authorization should be the JWT string. The operation is authorized after the volume server validates the JWT with jwt.signing.key.

JWT Summary:

  • JWT is set in /dir/assign or /dir/lookup response header Authorization
  • JWT is read from request header Authorization
  • JWT is valid for 10 seconds.
  • JWT only has permission to create/modify/delete one fileId.
  • The volume server HTTP access is only for read, and only if the fileId is known. There are no way to iterate all files.
  • All other volume server HTTP accesses are disabled when jwt.signing is enabled.

JWT for Read Access Control

The volume server can also check JWT for reads. This mode does not work with weed filer. But this could be useful if the volume server is exposed to public and you do not want anyone to access it with a URL, e.g., paid content.