eCryptfs技术问询：删除~/.ecryptfs目录会产生什么后果？

Short answer: You will permanently lose access to all your eCryptfs-encrypted data, with no way to recover it (unless you backed up critical files from this directory beforehand).

Let's break down why this is the case, based on how eCryptfs works:

• The most critical file in ~/.ecryptfs is wrapped-passphrase: This file stores your actual file encryption master key, encrypted using your login password. When you mount an eCryptfs directory, the system uses your login password to "unwrap" this master key into memory, which is what actually decrypts your files. If you delete this file, there's no way to retrieve the master key—your login password alone isn't enough, since it only unlocks the wrapped master key, not the files directly.
• If you used ecryptfs-setup-private to create an encrypted home/private directory, there are other important files here like Private.sig (a signature for verifying the master key's integrity). Without these, the system can't validate that any key you try to use is legitimate, so it won't decrypt your data.
• This directory also stores configuration details for eCryptfs mounts, like cached keys and mount parameters. Even if you tried to re-run setup commands or remount encrypted directories, the system would have no way to link back to the original encryption keys used for your existing files.

For your specific test scenario: The encrypted ~/test directory you created, along with the data file inside it, relies entirely on the master key stored in ~/.ecryptfs. Delete that directory, and you'll only see unreadable gibberish if you try to access those files again—there's no way to recover the original content.

As you noted in the documentation: Never lose or delete this directory—it's the linchpin of your eCryptfs encrypted data.

内容的提问来源于stack exchange，提问作者Yves