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A comment on Man Who Refused to Decrypt Hard Drives Still in Prison After Two Years. Parent comment

Re:Man Who Refused to Decrypt Hard Drives Still in Prison Af... by infinisil on Saturday September 02, 2017 @08:54AM (#15155724)
> Do they encrypt known CP files with the FileVault key and then compare?

This shouldn't work because if they had the key (which should be encrypted with the password) then they could also just decrypt the rest.

Somebody on IRC said that maybe the encrypted filesystem saves hashes of the files unencrypted, but not sure if Apple's FileVault does this.

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Re:Man Who Refused to Decrypt Hard Drives Still in Prison Af... by Pywarrior on Saturday September 02, 2017 @08:57AM (#15155738)
Storing hashes of unencrypted files, would that allow FileVault to verify it was decrypted without error?
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Re:Man Who Refused to Decrypt Hard Drives Still in Prison Af... by poizan42 on Saturday September 02, 2017 @09:02AM (#15155758)
The correct order is hash then encrypt, exactly so you can't do that. Now I don't know if FileVault is doing this correctly, but hopefully it does.

Edit: So two people have downvoted me without explanation. Is what I'm saying wrong?

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Re:Man Who Refused to Decrypt Hard Drives Still in Prison Af... by slaymaker1907 on Saturday September 02, 2017 @12:32PM (#15156854)
You could also hash, encrypt, then hash again if you wanted extra integrity without decrypting. This is technically done with HTTPS through the TCP hash.
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Re:Man Who Refused to Decrypt Hard Drives Still in Prison Af... by mdekkers on Saturday September 02, 2017 @12:14PM (#15156723)
two people have downvoted me without explanation

Sadly, that is the new normal for HN (and, I'll be downvoted for saying something like this)

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Re:Man Who Refused to Decrypt Hard Drives Still in Prison Af... by maaaats on Saturday September 02, 2017 @10:02AM (#15156008)
You can't unhash, so you could never retrieve the original file again.
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Re:Man Who Refused to Decrypt Hard Drives Still in Prison Af... by poizan42 on Saturday September 02, 2017 @10:04AM (#15156020)
What do you mean? You obviously store the encrypted file together with the encrypted hash.
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Re:Man Who Refused to Decrypt Hard Drives Still in Prison Af... by maaaats on Saturday September 02, 2017 @10:08AM (#15156044)
Then I guess me and the downvoters thought you meant hashing the files for encryption :)
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