Using Encryption

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Advanced > Miscellaneous Functions > Using Encryption

ClipMate uses 56-bit ARC4 encryption to encrypt individual clips.  This is strong enough to keep casual "snoopers" away, as significant knowledge of both encryption breaking and program cracking would be required to access the data once encrypted.  Since the data is also stored within the database in encrypted form, there are no easy "back door" methods to defeat the security by simply peeking at the underlying data files.

ClipMate's encryption is only applicable to TEXT clips.  If you attempt to encrypt a graphic, it will be ignored.  If you encrypt data containing TEXT but also other formats such as Rich Text or HTML, the other formats will be discarded.


Select a clip (or several clips) and use File | Encrypt.  You will be presented with the Encryption Key dialog box.  Enter a key that you can remember!  And not something too simple, or with repeating characters, such as "aaaa".  We recommend that you use the same encryption key for each clip, unless you have a reason to use (and remember) multiple keys.


When you attempt to access an encrypted clip, you will be presented with an extended version of the Encryption Key Dialog Box.

Enter the same key that you used to encrypt the clip in question.  For convenience, ClipMate can keep your key in memory and use it to decrypt subsequent clips.  You can specify how long to "remember" the key.  When time runs out, it will then start asking you again for the key.

Note that encryption keys are not the same as passwords.  With a password, either you get it right or you don't.  With encryption keys, you will always have access to the data - except that it will look like garbage if you enter an incorrect key.  This makes it more secure.

Decrypting is a temporary process.  ClipMate will use the key to decrypt the data, so that it can be viewed and placed back on the clipboard.  But once you scroll away from that clip, the data is deleted from memory and it must be re-decrypted if you want to access it again.  This will happen automatically if your key is still being "remembered", according to the time limit set in the dialog.

But let's suppose you decrypt a clip, and then paste it somewhere.  But now you are going to step away from your computer.  You should do several things:  1) use File | Forget Encryption Key to cause ClipMate to discard the key from memory.  2) Select another clip, so that you overwrite the clipboard with non-sensitive data.  Otherwise even if you close ClipMate, the recently-pasted data is still on the clipboard!

Checksum: Although ClipMate does not keep a record of your encryption keys, it uses a 4-byte checksum to see if data has been decrypted correctly or not.  If you enter an incorrect key, the checksum will fail, and the clip will not be displayed.  You'll be prompted to re-enter the key.  This is useful in preventing the display of garbage characters, which can cause display problems in the editor and causes some headaches for the spellchecker.

Note that since the checksum is encrypted as well (with the same key as the data), there is no security vulnerability here.  An attacker will not know the checksum without the proper key, so the checksum is useless to the attacker.


As a precaution, the titles of clips are replaced with a generic title when the clips are encrypted (unless you've already manually assigned a title with Ctrl+R).  Otherwise, the titles would give away your sensitive data.  So name them things like "Visa Number" or "eBay Password", which tell you what they are, without giving away the contents.

Recommended Practices:  To keep prying eyes away from your data, encrypt sensitive text clips.  Unless you have a good reason to use multiple encryption keys, we recommend using the same one.  Avoid overly simplistic keys with repeating characters such as "aaaa".  Use the Rename Title command (Ctrl+R) to assign meaningful, yet secure titles to your clips.  Usually, if a clip is important enough to encrypt, it's also important enough to assign a shortcut to.  So assign a shortcut while you're renaming the title.

Technical Notes:

ClipMate encrypts clear TEXT clips with 56-bit ARC4 (RC4), encoded with Base64 and appended to 6 salt bytes, and stored back into the database in encrypted form.  A CRC32 checksum is calculated, encrypted with the same ARC4 stream used to encrypt the data, and stored with the encrypted text.