cyclista said:
After much heartache it appears that the pdfs that I want to sign are protected and apart from Adobe nobody can allow me to sign or modify a protected document. However I downloaded iAnnotate and PDF expert. They are both good however PDF expert works way better to sign unprotected docs. Thanks for all you help.
GoodReader QUOTE
Data Protection (File Encryption)
GoodReader takes advantage of iOS's Data Protection API. This API encrypts files, to make sure that your data will be secure, even if your device gets lost or stolen. While this feature is designed to be as transparent and effortless as possible, there are some procedures that need to be performed to enforce data encryption. Also, some limitations apply, so please be sure to read the following section, if you want to use this feature.
Data Protection provides a fairly strong level of data security. If you use it properly, it will continue to protect your files even if an attacker jailbreaks your device and uses various hacking techniques to access encrypted files. You can also use Apple's Remote Wipe feature to erase all data remotely from a lost or stolen device.
Data Protection works in conjunction with the passcode that you use to unlock your device. If you don't lock your device with a passcode, your files will NOT be encrypted. However, locking a device with a passcode doesn't automatically mean that your files will be encrypted. The following conditions must also be met (we have divided them into two categories - Apple's prerequisites and GoodReader's usage rules).
Apple's side of protection:
Since Data Protection relies on a special hardware to encrypt files, it doesn't work on older iOS devices. It does work on the following ones: all iPad models, iPhone models starting with 3GS and newer, iPod touch models starting with 3rd generation and newer.
iOS 4.0 or later is required
Data Protection is active only if you enable Passcode Lock in main device Settings, General section. If you don't use passcode lock, your files will not be encrypted.
The trickiest part of preparing your device to use Data Protection comes to play when your device previously used to work under an older version of iOS. Data Protection requires disk drive of your device to be fully reformatted in a special secure mode. This automatically happens when you fully restore a device to iOS 4.0 or later, but it does NOT happen when you simply upgrade from iOS 3.x to iOS 4.x. During a simple upgrade process your disk drive is left in the older insecure mode. In this case you will have to perform a full restore (“full-erase install&rdquo
of your device to iOS 4.0 or later. The following paragraph describes how to check if your device is fully prepared for Data Protection or not.
To check if your device is fully prepared to encrypt your files, go to main device Settings, General section, and select Passcode Lock. Make sure that Passcode is turned on. If Passcode is on, and your device's disk is properly formatted, you will see the “Data protection is enabled” label at the very bottom of Pascode Lock settings window:
If you see this label, your device is fully prepared to encrypt files. The rest of setup is done in GoodReader.
As an additional security measure, tell iTunes to encrypt your backup files
If you represent a company that manages a set of iOS devices via Configuration Profiles, enforce a certain policy on your managed devices: require that Data Protection is enabled, require password length and complexity, require maximum passcode grace period, require encrypted iTunes backups. If a device is compromised, instantly use Remote Wipe.
GoodReader's side of protection:
In GoodReader there are two passwords to restrict the access to physical files - app startup password and password for protecting individual files and folders. Both of them are set up in GoodReader app settings, General section. Both these passwords apply encryption to files.
It is important to understand that GoodReader itself doesn't encrypt or decrypt your files. It does two things - restricts the access to protected files via GoodReader's own user interface, and asks iOS to encrypt certain files (or all of them, if you're using app startup password). iOS, in its turn, locks these files within a few seconds after you lock your device with a passcode, and instantly unlocks them when you unlock your device with a passcode. It means that when you unlock your device with a passcode, all your files become decrypted and fully accessible, even if GoodReader app is not being run at the moment, and you haven't entered any of GoodReader's passwords yet. So, if your device is unlocked, GoodReader will prevent the access to protected files via its own user interface, but nothing prevents from copying these files via, for example, File Sharing section of iTunes (USB transfer), without knowing GoodReader's passwords. So please be sure to ALWAYS lock your device with a passcode, even if you leave it just for a minute. This will turn the physical hardware-based protection on. And while Auto-Lock option in main device Settings may be of great help with this, it never hurts to manually lock your device every time you leave it.
GoodReader must explicitly tell iOS about files it wants to encrypt. This brings up an issue when you transfer files to GoodReader without GoodReader's direct participation, for example, using File Sharing in iTunes, or using some other undocumented technique. GoodReader takes care of everything when it directly participates in transferring process (when using documented WiFi transfer, or downloading files from remote servers via GoodReader's user interface). But if you have transferred files to GoodReader's protected zone using techniques that do not involve direct GoodReader's participation, you must make sure that GoodReader learns about these new files and explicitly asks iOS to encrypt them. You do it by simply launching GoodReader and browsing to a folder where these new files are located. Once GoodReader opens that folder and shows you this folder's list of files, it instantly discovers all new files being shown in a list, and tells the system if these files need to be encrypted or not.
Things to consider:
Your data protection is only as good as your passcode is. If you use “1234”, your name, your birthdate or your zodiac sign for a passcode, rest assured - an attacker will crack it in a minute. Choose strong alphanumeric passwords consisting of random characters, not words. Enter your passcode only when nobody's looking. And don't forget to change your passwords periodically.
GoodReader can work with files on a locked device under certain circumstances. For instance, it can play audio when locked, or upload/download files for a short period of time (until WiFi module shuts down). However, if you use Data Protection, and a file you're working with is in a protected zone, iOS will physically block the access to this file within several seconds after locking, so don't be surprised if playback of a protected audio file suddenly stops when you lock a Data Protection-enabled device.
Sent from my iPad using iPF