>Now with iMessage in iCloud, I do not know how the E2E encryption is done
It isn't done. Apple holds the master keys. The trust is that the iCloud server is not compromised.
It isn't done. Apple holds the master keys. The trust is that the iCloud server is not compromised.
> Messages in iCloud also uses end-to-end encryption. If you have iCloud Backup turned on, your backup includes a copy of the key protecting your Messages. This ensures you can recover your Messages if you lose access to iCloud Keychain and your trusted devices. When you turn off iCloud Backup, a new key is generated on your device to protect future messages and isn't stored by Apple.
https://pxlnv.com/linklog/improving-imessage-encryption/
> During an interview with Apple blogger and Daring Fireball’s owner John Gruber, Federighi said that the company has figured out a way to do syncing while still remaining unable to read your iMessages.