+fscrypt is not guaranteed to protect confidentiality or authenticity
+if an attacker is able to manipulate the filesystem offline prior to
+an authorized user later accessing the filesystem.
How does fscrypt / Android protect against Evil Maid attack. ?
_However_, an "Evil Maid" attacker can probably still do other, perhaps much
more effective attacks --- e.g.
::
. Or they could attack the actual
file contents encryption which is not authenticated. Or they could mess around
with filesystem metadata on the userdata partition, which is neither encrypted
nor authenticated.
In specific, the scenario I had in mind was the above threat.
I suppose that dm-integrity could be used to protect against some of those
attacks, but of course it would not protect against hardware key loggers, etc.
OK.
I think AE is the only good solution for this, File-name encryption
at this stage won't solve any kind of Evil Maid attack, (as it was
quoted somewhere else in ML).
Further, below, is define but not used.
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#define FS_AES_256_GCM_KEY_SIZE 32
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Thanks, Anand
