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> For example, conversations which take place over iMessage and FaceTime are protected by end-to-end encryption so no one but the sender and receiver can see or

by evadne 13y ago

> For example, conversations which take place over iMessage and FaceTime are protected by end-to-end encryption so no one but the sender and receiver can see or read them. Apple cannot decrypt that data. I don’t know, then, why when I do an iCloud restore on a brand new device, all existing messages are recovered. Is this a way to recover all past messages that’s not really addressed, if I can still recover all historical messages after replacing all devices connected to an iCloud account at once? Cursory links: http://security.blogoverflow.com/2012/09/qotw-34-imessage-what-security-features-are-present/ http://security.blogoverflow.com/2012/09/qotw-34-imessage-wh... https://github.com/meeee/pushproxy https://github.com/meeee/pushproxy http://imfreedom.org/wiki/IMessage http://imfreedom.org/wiki/IMessage

atirip 13y ago
Hmm, if they are encrypted with your password and Apple does only store hash of that password for login and encrupted messages then everything is ok? I assume that when you change your iCloud password, the old messages are not visible anymore. Anybody to verify that?
- __alexs 13y ago
  Given that you send your password in platin text to Apple whenever you login this does not seem like a particularly interception resistant protocol. Apple just need to wait until you login again and then send the encrypted data, and your password to the intelligence services?
  - morgante 13y ago
    Do we know that they send your password in plain text?
    - nknighthb 13y ago
      For all intents and purposes, they must, at least when you login via a web browser.
      - morgante 13y ago
        Not technically. You can do client-side encryption so that only the hash is sent, via Javascript.
- nknighthb 13y ago
  > I assume that when you change your iCloud password, the old messages are not visible anymore. I'm not sure why that would be true. I posit that such a system could work like this: * An asymmetric keypair (e.g. RSA or ECC) is generated and stored on Apple's servers. The private key is encrypted with the user's password, which is not retained by Apple except in a hashed form. * When a device is added, the private key is decrypted using the password and sent to the device. * When your password is changed, either A) the private key is decrypted with the original password, and re-encrypted with the new password, or B) the private key is decrypted, used to decrypt all data, thrown away, and a new keypair is generated, with which all data is then re-encrypted. It is, of course, obvious that Apple could, in theory, capture your plaintext password somewhere in there and use it to decrypt messages. There are ways around this, such as devices doing the key decryption locally and only ever sending a derived/hashed form of your password to the server, and using a different derived/hashed form for encryption. However, since you can log in to iCloud and Apple's store with your Apple ID in a browser, there is still no effective defense against Apple capturing your plaintext password (unless you care to perform a detailed inspection of a bunch of JavaScript every single time you load any content from Apple's servers).
  - ninjay 13y ago
    > The private key is encrypted with the user's password, which is not retained by Apple except in a hashed form. > the private key is decrypted using the password and sent to the device. wait, where is this private key coming from then? your other devices?
    - nknighthb 13y ago
      Either Apple would generate it server-side, or the first device to "sign up" would generate it. Remember, I'm only explaining a hypothetical method by which the Apple system could work, consistent with Apple's statements and behavior I've observed from my iPhones, iPads, and Macs. It's not an explanation of a strictly secure system.
      - ninjay 13y ago
ParkerK 13y ago
>why when I do an iCloud restore on a brand new device, all existing messages are recovered Because they're stored locally on your phone, and then encrypted as a backup file. The statement is saying that the messages aren't sent in the open, so no one (including Apple) can eavesdrop. Of course you can get them from your backup, if you have access to a password, you can always access encrypted data with it.
brisance 13y ago
The following support document states that you get 5GB of free iCloud storage of messages in the form of iMessages, SMS and MMS. http://support.apple.com/kb/HT4859?viewlocale=en_US&locale=en_US http://support.apple.com/kb/HT4859?viewlocale=en_US&locale=e... It doesn't state how the iCloud backup is stored however.
comex 13y ago
Of course, if you're concerned about privacy, it may be a good idea to abstain from iCloud backup/sync and not send all your notes, contacts, etc. to a remote server in the first place. iTunes backups may be relatively clumsy, but they still work.

by evadne 13y ago

atirip 13y ago

Hmm, if they are encrypted with your password and Apple does only store hash of that password for login and encrupted messages then everything is ok? I assume that when you change your iCloud password, the old messages are not visible anymore. Anybody to verify that?

__alexs 13y ago
Given that you send your password in platin text to Apple whenever you login this does not seem like a particularly interception resistant protocol. Apple just need to wait until you login again and then send the encrypted data, and your password to the intelligence services?
- morgante 13y ago
  Do we know that they send your password in plain text?
  - nknighthb 13y ago
    For all intents and purposes, they must, at least when you login via a web browser.
    - morgante 13y ago
      Not technically. You can do client-side encryption so that only the hash is sent, via Javascript.
nknighthb 13y ago
> I assume that when you change your iCloud password, the old messages are not visible anymore. I'm not sure why that would be true. I posit that such a system could work like this: * An asymmetric keypair (e.g. RSA or ECC) is generated and stored on Apple's servers. The private key is encrypted with the user's password, which is not retained by Apple except in a hashed form. * When a device is added, the private key is decrypted using the password and sent to the device. * When your password is changed, either A) the private key is decrypted with the original password, and re-encrypted with the new password, or B) the private key is decrypted, used to decrypt all data, thrown away, and a new keypair is generated, with which all data is then re-encrypted. It is, of course, obvious that Apple could, in theory, capture your plaintext password somewhere in there and use it to decrypt messages. There are ways around this, such as devices doing the key decryption locally and only ever sending a derived/hashed form of your password to the server, and using a different derived/hashed form for encryption. However, since you can log in to iCloud and Apple's store with your Apple ID in a browser, there is still no effective defense against Apple capturing your plaintext password (unless you care to perform a detailed inspection of a bunch of JavaScript every single time you load any content from Apple's servers).
- ninjay 13y ago
  > The private key is encrypted with the user's password, which is not retained by Apple except in a hashed form. > the private key is decrypted using the password and sent to the device. wait, where is this private key coming from then? your other devices?
  - nknighthb 13y ago
    Either Apple would generate it server-side, or the first device to "sign up" would generate it. Remember, I'm only explaining a hypothetical method by which the Apple system could work, consistent with Apple's statements and behavior I've observed from my iPhones, iPads, and Macs. It's not an explanation of a strictly secure system.
    - ninjay 13y ago

ParkerK 13y ago

>why when I do an iCloud restore on a brand new device, all existing messages are recovered Because they're stored locally on your phone, and then encrypted as a backup file. The statement is saying that the messages aren't sent in the open, so no one (including Apple) can eavesdrop. Of course you can get them from your backup, if you have access to a password, you can always access encrypted data with it.

brisance 13y ago

The following support document states that you get 5GB of free iCloud storage of messages in the form of iMessages, SMS and MMS. http://support.apple.com/kb/HT4859?viewlocale=en_US&locale=en_US http://support.apple.com/kb/HT4859?viewlocale=en_US&locale=e... It doesn't state how the iCloud backup is stored however.

comex 13y ago

Of course, if you're concerned about privacy, it may be a good idea to abstain from iCloud backup/sync and not send all your notes, contacts, etc. to a remote server in the first place. iTunes backups may be relatively clumsy, but they still work.