// +optional
  optional UserSubject user = 2;

  // `group` matches based on user group name.
  // +optional
  optional GroupSubject group = 3;

  // `serviceAccount` matches ServiceAccounts.
  // +optional
  optional ServiceAccountSubject serviceAccount = 4;
}

// UserSubject holds detailed information for user-kind subject.
message UserSubject {
  // `name` is the username that matches, or "*" to match all usernames.

  // +optional
  optional UserSubject user = 2;

  // `group` matches based on user group name.
  // +optional
  optional GroupSubject group = 3;

  // `serviceAccount` matches ServiceAccounts.
  // +optional
  optional ServiceAccountSubject serviceAccount = 4;
}

// UserSubject holds detailed information for user-kind subject.
message UserSubject {
  // `name` is the username that matches, or "*" to match all usernames.

  // +optional
  optional UserSubject user = 2;

  // `group` matches based on user group name.
  // +optional
  optional GroupSubject group = 3;

  // `serviceAccount` matches ServiceAccounts.
  // +optional
  optional ServiceAccountSubject serviceAccount = 4;
}

// UserSubject holds detailed information for user-kind subject.
message UserSubject {
  // `name` is the username that matches, or "*" to match all usernames.

  // +optional
  optional UserSubject user = 2;

  // `group` matches based on user group name.
  // +optional
  optional GroupSubject group = 3;

  // `serviceAccount` matches ServiceAccounts.
  // +optional
  optional ServiceAccountSubject serviceAccount = 4;
}

// UserSubject holds detailed information for user-kind subject.
message UserSubject {
  // `name` is the username that matches, or "*" to match all usernames.

  // will pass the tokens in VolumeContext in the CSI NodePublishVolume calls.
  // The CSI driver should parse and validate the following VolumeContext:
  // "csi.storage.k8s.io/serviceAccount.tokens": {
  //   "<audience>": {
  //     "token": <token>,
  //     "expirationTimestamp": <expiration timestamp in RFC3339>,
  //   },
  //   ...
  // }
  //

  // will pass the tokens in VolumeContext in the CSI NodePublishVolume calls.
  // The CSI driver should parse and validate the following VolumeContext:
  // "csi.storage.k8s.io/serviceAccount.tokens": {
  //   "<audience>": {
  //     "token": <token>,
  //     "expirationTimestamp": <expiration timestamp in RFC3339>,
  //   },
  //   ...
  // }
  //