"Live Long & Prosper" <sp...@the.helm> wrote in
news:XnsA35F9A348F6...@216.151.153.44:
> So have you succeded in your statement from
http://cenocipher.crypt.to
> under details? I have included a copy below to refer too. I know I
> would[n't] want ANY of my info to be written to disc!
>
> =====
>
> From the section on Details:
>
> In addition, all efforts are made never to save any unencrypted data
> to disk, either on the sender's or receiver's side of the operation,
> unless absolutely necessary.
>
Presently there are only two scenarios under which CenoCipher
temporarily writes decrypted data to disk, and cannot avoid doing so:
1) If the encrypted cipher-package received by the recipient contains
one or more file attachments included along with the message text, then
upon successful decryption these files are by default held only in
volatile memory as part of a larger contiguous data block, with their
names displayed on-screen for the recipient to see, but their contents
not written to disk. If however the recipient then chooses to double-
click on the filename(s) (or click the "open" button) in order to
actually view/open those files with their corresponding default program
under Windows, then the file(s) in question must first be written to
disk in order for Windows to load them into the appropriate viewing
program, since it cannot process them otherwise.
For example if a file named NightSky.jpg was included in the cipher-
package, at first upon decryption its name would be shown and the
unencrypted bytes would only exist in memory as a non-demarcated portion
of the greater data block to which it belongs. Once the user decides to
view the Jpg in question, those bytes must be written to a temporary
folder on disk as a newly created file, and this new file then opened by
Windows using the default JPEG viewer or whatever. Windows simply cannot
access the NightSky.jpg file to open it, without its existing as a
physical file on disk first. However CenoCipher at least does not
perform this operation until such time as the user makes the decision to
open said file, and all such files are subsequently and automatically
deleted upon closure of the program.
2) If the received cipher-package is itself so gigantically large
(usually as a result of containing large/many included sub-files) that
it cannot be decrypted into a temporaty memory block because of its
excessive size, then the only option is to write the decrypted data blob
itself as a new file in a temporary folder on disk, and work with this
blob-file in the same way as would normally be done with a memory block.
Again, accessing individual files contained within this blob would
result in their being written separately to disk as well, and again all
files (individual and giant blob) are automatically deleted upon program
closure.
For this second case, we currently have the size-limit arbitrarily set
at 100 megabytes, where anything larger is decrypted onto a disk-blob
rather than into volatile memory. We could of course set it to a larger
figure, but are trying to accommodate older computers which do not have
huge amounts of system memory available.
Other disk-writes performed by CenoCipher are of course the encrypted
cipher-file being created and made available for sending as an email
attachment, and also a small config/preference file that is written upon
program closure in order to remember which program options (checkboxes,
menu selections etc) where chosen previously for restoration upon next
launch.