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GeneralRe: Apple Says 'No' Pin
Duncan Edwards Jones17-Feb-16 5:34
professionalDuncan Edwards Jones17-Feb-16 5:34 
GeneralRe: Apple Says 'No' Pin
Kevin Marois17-Feb-16 5:36
professionalKevin Marois17-Feb-16 5:36 
GeneralRe: Apple Says 'No' Pin
Nish Nishant17-Feb-16 6:05
sitebuilderNish Nishant17-Feb-16 6:05 
GeneralRe: Apple Says 'No' Pin
Albert Holguin17-Feb-16 6:34
professionalAlbert Holguin17-Feb-16 6:34 
GeneralRe: Apple Says 'No' Pin
Vark11117-Feb-16 6:34
Vark11117-Feb-16 6:34 
GeneralRe: Apple Says 'No' Pin
Albert Holguin17-Feb-16 6:45
professionalAlbert Holguin17-Feb-16 6:45 
GeneralRe: Apple Says 'No' Pin
kalberts17-Feb-16 22:58
kalberts17-Feb-16 22:58 
GeneralRe: Apple Says 'No' Pin
kalberts17-Feb-16 23:44
kalberts17-Feb-16 23:44 
Duncan Edwards Jones wrote:

If the file exists on the phone and was encrypted using an existing version of the data, how would installing a new version of the iOS allow easier unencryption?
Unless the user specifies the full encryption key every time the encrypted information is accessed, the software does know the key. It is stored somewhere in the file system. Move that flash (/disk, for general PCs) over to another machine, as a secondary storage device, and the key can be read by that other machine.

Sure, the key is usually encrypted; you won't find it in cleartext. But the OS/Application knows how to decrypt it. It must know, in order to decrypt the info for the proper user. But in a standard version, the OS/App refuses to do it until the operater has authenticated himself. The special OS edition on the other machine may be willing to decrypt the key without the the owner authenticating himself, e.g. presenting a password or fingerprint.

Couldn't that info, given by the user, be (part of) what encrypts the key, so that an intruder would have to know that?
But the OS knows that, too. It must know the PW (or some transformation of it) in order to check that the user gives the right one. So the alternate OS version may pretend that it has just read from the user a PW corresponding to the expected one, even if no user ever specified anything.

Whether you install the alternate OS version on the same device or you move the storage device (flash/disk) to another machine makes no essential difference, as long as there exists a possiblity for loading a new OS version without logging in to the machine. In the old days, that wasn't always the case, but with modern automatic over-the-air updates and fixes, it it probably possible to replace all essential parts of the OS that way.

The only safe encryption is where you are the one generating the key, the only one knowing it, and you never present it to the OS or to any application. For standard PC use, I would like to have a USB dongle where I can load, say, my X.509 certificates into a flash area that is not adressable across the USB interface; only the processor in the dongle can see it. So the PC sends the ciphertext across the USB interface, the dongle decrypts it, and returns hte cleartext to the PC across the USB interface. (Or it receives cleartext and returns ciphertext.) In many applications (such as S-MIME), the ciphertext will not be the full document text but e.g. a one-time 3DES or AES256 key, used for the text body, but in principle, the dongle could encrypt/decrypt the entire text body.

This dongle could itself require authentication. E.g. it can have a Bluetooth [Smart] interface to your smartphone, requesting a 6-digit PIN to be keyed on the phone. No keylogger on the PC will be able to pick it up (the way it can pick up any PIN, PW or key you type at the PC keyboard). So to access an encrypted document would require both the right USB dongle with the proper keys loaded, the right smartphone for authentication, and knowledge of the PIN requested by the dongle. (Plus, implicitly, the ability to unlock the smartphone, eg. by fingerprint.) In principle, a keylogger may be installed on the phone, but the risk of the intruder knowing how those digits typed are actually used - as a PIN code for some independent dongle - is rather small.

The biggest problem is to make e.g. an email program use that dongle for decrypting/encrypting the one-time-key (or the entire text body). Even if there exists standard encryption APIs, there is a great risk that common mail programs insists on accessing the X.509 certificate itself; maybe it doesn't use that standard encryptin API at all. So if I make myself such a dongle (in fact, I do have access to a programmable USB dongle that could do the job - I just have to learn to develop software for it!), I guess I would have to obtain some open-source email reader (such as Thunderbird) to adapt the source code for it. I guess that I might get the time to complete that project as soon as I retire as an old age pensioner...
GeneralRe: Apple Says 'No' Pin
Jeremy Falcon17-Feb-16 6:00
professionalJeremy Falcon17-Feb-16 6:00 
GeneralRe: Apple Says 'No' Pin
Albert Holguin17-Feb-16 6:35
professionalAlbert Holguin17-Feb-16 6:35 
GeneralRe: Apple Says 'No' Pin
Jeremy Falcon17-Feb-16 6:36
professionalJeremy Falcon17-Feb-16 6:36 
GeneralRe: Apple Says 'No' Pin
GuyThiebaut17-Feb-16 7:31
professionalGuyThiebaut17-Feb-16 7:31 
GeneralRe: Apple Says 'No' Pin
Kornfeld Eliyahu Peter17-Feb-16 8:39
professionalKornfeld Eliyahu Peter17-Feb-16 8:39 
GeneralRe: Apple Says 'No' Pin
megaadam17-Feb-16 12:08
professionalmegaadam17-Feb-16 12:08 
GeneralRe: Apple Says 'No' Pin
Steve Wellens17-Feb-16 18:09
Steve Wellens17-Feb-16 18:09 
GeneralRe: Apple Says 'No' Pin
mbb0117-Feb-16 22:32
mbb0117-Feb-16 22:32 
GeneralRe: Apple Says 'No' Pin
Kiriander17-Feb-16 22:49
Kiriander17-Feb-16 22:49 
GeneralRe: Apple Says 'No' Pin
Andy Hoffmeyer18-Feb-16 2:34
Andy Hoffmeyer18-Feb-16 2:34 
AnswerRe: Apple Says 'No' Pin
Plamen Dragiyski18-Feb-16 3:12
professionalPlamen Dragiyski18-Feb-16 3:12 
GeneralRe: Apple Says 'No' Pin
TealHaze18-Feb-16 3:26
TealHaze18-Feb-16 3:26 
AnswerRe: Apple Says 'No' Pin
Plamen Dragiyski18-Feb-16 4:13
professionalPlamen Dragiyski18-Feb-16 4:13 
GeneralRe: Apple Says 'No' Pin
dgreenx18-Feb-16 3:32
dgreenx18-Feb-16 3:32 
GeneralRe: Apple Says 'No' Pin
MikeTheFid18-Feb-16 4:04
MikeTheFid18-Feb-16 4:04 
GeneralRe: Apple Says 'No' Pin
Jim McCool18-Feb-16 4:43
Jim McCool18-Feb-16 4:43 
GeneralRe: Apple Says 'No' Pin
scmtim18-Feb-16 5:06
scmtim18-Feb-16 5:06 

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