TweetFollow Us on Twitter

Safeguarding "sensitive data" using encrypted disk images

Volume Number: 22 (2006)
Issue Number: 4
Column Tag: Programming

Safeguarding "sensitive data" using encrypted disk images

by Aaron Adams

With Tiger's release, it's now easier than ever to keep your (imagine me making big finger quotes here) "sensitive data" secure. You know the "sensitive data" I'm talking about. The kind that's not intended for casual viewing. There's also the real sensitive data. Payroll records, bonus charts, proprietary data, your secret plan for world peace. It's only a matter of time until someone using a shared Mac performs an innocuous Spotlight search that suddenly turns up a cornucopia of sensitive data associated with you. Depending on who finds it, you could lose your job, lose business, lose your significant other, or just have more headaches than you really need. An ounce of prevention is worth a ton of cure.

Hiding such things from Spotlight is a good idea. To do that, you can create an encrypted disk image that is password protected to keep nosy users out. The contents of the image won't appear in Spotlight unless the image is mounted.

To begin, go to the /Applications/Utilities folder (press command-shift-u in the Finder) and start up Disk Utility. Click File, New, and Disk Image from Folder. This will create something called a sparse image. Sparse images are initially only as big as the data they contain, but have the advantage of expandability later.

Select the folder where your sensitive data is located and press the Image button. Name the image. Select read/write from the Image Format drop-down. Click the Encryption drop-down and choose AES-128 (recommended). Select a save location and press Save.

You will then be prompted for a password. This is the password Disk Utility will use to encrypt the data and that you will have to enter it each time the image is mounted. Do yourself a favor and make the password hard to guess. Do yourself another favor and uncheck the box marked Remember password (add to Keychain). It defeats the purpose of encrypting and password protecting an image if you're going to automate its access with Keychain. Click OK after entering your new password. [Ed Note: Do yourself a final favor - make this password something different than your login password.]

A new disk image containing your data in encrypted form will be created. When you double-click the image to mount it, you will be prompted for the password. Drag and drop new sensitive data onto the image as desired for permanent safekeeping.

Over time, your collection will probably continue to grow and will become larger than the sparse image you just created. As I said before, sparse images can be expanded to any size you need, but the drawback is that you have to do it through the command line.

Open Terminal and enter this command:

hdiutil resize -size xxx /path/to/image.dmg

where xxx is the size you want to the image to be in megabytes or gigabytes. For example, 500mb or 4.7gb.

Now your sensitive data, or "sensitive data", is protected from prying eyes and accidental finds. Backups are a simple one-file copy operation. You stay out of trouble, off the unemployment lines, and in the closet. I love it when technology helps people.


Aaron Adams is a Mac consultant and network whipping boy located in Dayton, Ohio. You may also remember him from Apple's "Switch" campaign a few years ago. You can e-mail him at aaron@aaronadams.net.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Galaxy of Trian (Games)
Galaxy of Trian 1.1.0 Device: iOS Universal Category: Games Price: $6.99, Version: 1.1.0 (iTunes) Description: Galaxy of Trian is an exciting, fast paced digital board game based on the highly acclaimed tabletop title. | Read more »
Dead In Bermuda (Games)
Dead In Bermuda 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: | Read more »
The Little Fox (Games)
The Little Fox 1.0.1 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0.1 (iTunes) Description: The Little Fox is an alternative perspective on the world-renowned ‘fairy tale for adults', The Little Prince by Antoine de... | Read more »
How to get more cars in CSR Racing 2
NaturalMotion and Zynga brought a lot of real life cars to the table for CSR Racing 2. From souped up everyday rides made by Nissan and Hyundai to supercars produced by the likes of McLaren and Pagani, there really is something for everyone. [... | Read more »
Crypt of the NecroDancer Pocket Edition...
Crypt of the NecroDancer Pocket Edition 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Crypt of the NecroDancer is an award winning hardcore roguelike rhythm game. Move to the music and... | Read more »
Gear-grinding puzzle title Inner Circle...
If you saw our post earlier this month announcing the imminent release of ZPlay’s new creation, Inner Circle, you’ll be happy to know that it’s now available on the App Store. Established in 2010, developer and publisher ZPlay have taken the... | Read more »
CSR Racing 2: Your guide to what's...
CSR Racing 2, or CSR2, as it likes to call itself, has finally arrived. The follow-up to the immensely popular drag racing game CSR Racing is the first release from NaturalMotion since the studio's acquisition by Zynga in early 2014. [Read more] | Read more »
Nanuleu (Games)
Nanuleu 1.1 Device: iOS Universal Category: Games Price: $2.99, Version: 1.1 (iTunes) Description: Nanuleu is a strategy game where you take control of ancient magical trees that protect the land from an invading dark force. A... | Read more »
The Slaughter: Act One (Games)
The Slaughter: Act One 1.0.323 Device: iOS Universal Category: Games Price: $3.99, Version: 1.0.323 (iTunes) Description: “The game mixes realism and surrealism to create a story that can cause just as much laughter as fear. A-” -... | Read more »
NEO TURF MASTERS (Games)
NEO TURF MASTERS 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: NEOGEO’s legendary golf game is back, in a brand-new mobile version with touch controls! NEO TURF MASTERS (also known as “BIG... | Read more »

Price Scanner via MacPrices.net

New App Reminds Us to Put Down Our Phones and...
Mode, a new smartphone app that makes us more mindful of how we use our devices, debuts in the app stores today. The Mode app tracks time spent in different modes of day-to-day life without... Read more
ZuumSpeed Personalized Speedometer + HUD For...
RMKapps has announced the release and immediate availability of ZuumSpeed 1.0, its personalized speedometer plus heads up display for iOS devices. ZuumSpeed gives users over 18 custom fonts available... Read more
Apple refurbished clearance 15-inch Retina Ma...
Apple has Certified Refurbished 2014 15″ 2.2GHz Retina MacBook Pros available for $1609, $390 off original MSRP. Apple’s one-year warranty is included, and shipping is free. They have refurbished 15... Read more
9-inch 128GB Silver iPad Pro on sale for $50...
B&H Photo has the 9.7″ 128GB Silver Apple iPad Pro on sale for $699 including free shipping plus NY tax only. Their price is $50 off MSRP. Read more
Why Use Indie Opera And Vivaldi Instead Of Sa...
For many years my web browser workhorses were various permutations and spinoffs of the Netscape/Mozilla/Firefox Open Source platform, and the Norwegian indie browser Opera, which I took a shine to... Read more
Western Digital Launches Worlds Fastest 256GB...
At the Mobile World Congress in Shanghai Western Digital Corporation this week introduced a new suite of 256 gigabyte (GB) microSD cards, which includes the new 256GB SanDisk Extreme microSDXC UHS-I... Read more
KeyCue 8.1 Integrates With Typinator To Displ...
Ergonis Software has released KeyCue 8.1, a new version of the company’s keyboard shortcut cheat sheet. KeyCue 8 introduced a new way to define a wide variety of triggers, which can be used to... Read more
Save up to $600 with Apple refurbished Mac Pr...
Apple has Certified Refurbished Mac Pros available for up to $600 off the cost of new models. An Apple one-year warranty is included with each Mac Pro, and shipping is free. The following... Read more
21-inch 2.8GHz iMac on sale for $1199, save $...
Amazon has the 21″ 2.8GHz iMac (model #MK442LL/A) on sale for $1199.99 including free shipping. Their price is $100 off MSRP, and it’s the lowest price available for this model. Read more
13-inch 2.5GHz MacBook Pro (Apple refurbished...
Apple has Certified Refurbished 13″ 2.5GHz MacBook Pros available for $829, or $270 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free: - 13″ 2.5GHz MacBook Pros... Read more

Jobs Board

*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* iPhone 6s and New Products Tester Ne...
…we therefore look forward to put out products to quality test for durability. Apple leads the digital music revolution with its iPods and iTunes online store, Read more
*Apple* iPhone 6s and New Products Tester Ne...
…we therefore look forward to put out products to quality test for durability. Apple leads the digital music revolution with its iPods and iTunes online store, Read more
*Apple* iPhone 6s and New Products Tester Ne...
…we therefore look forward to put out products to quality test for durability. Apple leads the digital music revolution with its iPods and iTunes online store, Read more
*Apple* Retail - Multiple Positions, Willow...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.