Function load_passphrase_from_secrets_file 

pub fn load_passphrase_from_secrets_file(
    secret_handling: NonAdministrativeSecretHandling,
    system_user: &User,
    backend_user: &str,
) -> Result<Passphrase, Error>

Reads a secret from a secret file location of a user and returns it as a Passphrase.

The secret file location is established based on the chosen secret_handling, system_user and backend_user.

Notes

This function must be called using an unprivileged user, as the path is assumed to be in that user’s home directory. If systemd-creds(1) based encryption is used, then the same user used to encrypt the secret must be used to decrypt the secret.

Errors

Returns an error if

• the effective user ID of the calling user is that of root,
• the secret is a plaintext file, but reading it as a string fails,
• the secret is encrypted using systemd-creds(1), but
  • systemd-creds(1) cannot be found,
  • or the systemd-creds(1) command fails to execute,
  • or the systemd-creds(1) command returned with a non-zero exit code,
  • or the returned output cannot be converted into valid UTF-8 string