Create An Encrypted DMG

If you’ve got sensitive files you can secure them inside an encrypted DMG. It’s far less drastic than using Fire Vault, and it only takes a minute to implement.

People new to computers often confuse file permissions with encryption. Permissions can easily be circumvented. Any user with admin rights on the computer can change the permissions on a file. More importantly, anyone can take the disk and connect it to a different machine and change the permissions.

Encrypted files are different. The only way to access an encrypted file is with the password. Permissions rely on the security of the operating system for protection. Encrypted files have self-contained security, which also makes them portable.

You might want to make a back up of your novel and store it with your web host. But how do you know the web host won’t snoop? Tuck your files into an encrypted DMG before uploading and you’re all set.

When you create a DMG you’re prompted to add the password to your keychain. That would defeat the purpose of the DMG in most cases. Chances are you’re encrypting files that aren’t going to be on your computer anyway. If they are going to remain on your computer consider leaving the password off the keychain to greatly enhance the security.

You could encrypt your entire home folder with Fire Vault, but that seems like a big step for most people. If something goes wrong or you can’t come up with the password you’ll be locked out of your own data, along with everyone else. Murphy only encrpyts files that are truly sensitive. Locking everything down doesn’t make sense.

When you’re done working with your volume eject it, don’t just close the window. Once ejected the volume requires the password for access. When you want to store the file elsewhere just copy the DMG file, not the volume.

OS X Personal Web Sharing

Your Mac has a web server built right in. It’s handy for testing a site when you don’t have Internet access. Or for serving files at home or in a small office. From a PC you might find it easier to access Mac files using Personal Web Sharing than other file sharing services.

Turning on the service is nothing more than a checkbox. From there you simply place files in the Sites folder within your own home folder. You’ll want to replace the index file that’s placed there by default. The index file shows information on the Apache web server that powers Personal Web Sharing. You could publish an iWeb site to the Sites folder - or copy one from somewhere else.

You can access Apache support documentation on your own machine too. Once you’ve activated Personal Web Sharing visit http://localhost/manual/.

Configuring Apache involves editing text files. There’s plenty of documentation but if you’re not familiar with web servers you’ll have some research to do before making any big changes.

In the screencast Murphy simply removes the default index.html file. Without an index file Apache will display the files and folders in your Sites folder. It’s not pretty, but it makes big lists of files readily available on your network.

The important concept: A web URL often refers to an underlying folder with a different name. With web servers the part of a URL that equates to a folder in your file system is called an alias. For example, the URL http://murphymac.com/archive might point to a folder called backup_store in the file system on the machine hosting the web content - rather than a folder called ‘archive’.

You Mac running Personal Web Sharing can be accessed across the Internet if you allow port 80 in on your router. Click for more information about port forwarding. Always use caution when allowing any unsolicited traffic into your network.

Check back soon, we’ll take a closer look at using Apache and Personal Web Sharing.

Easter Project #1

Folder Actions Via SSH - Retrieving Files on Your Mac From a PC

You’re going to be away from your Mac for the holiday weekend? What if you need some important files from your G5 while you’re gone? What if you only have access to a PC at Aunt Millie’s house?

We’ve still got ways to connect and retrieve files. Like using SSH to mail an attachment from a remote machine. You don’t need a screencast, Murphy’s already given you all the pieces.

First, set up a Folder Action on the machine you’ll be connecting to via SSH. Murphy has a screencast on sending email attachments to a predetermined address. Make sure your router lets port 22 in. You can learn more about port forwarding in the screencast on VNC.

Then you can make an SSH connection to the computer from just about anywhere. Use the zip command to package up multiple files if you’re not just emailing a lone file. Copy the file to your Folder Action equipped folder using SSH. The Folder Action will still kick in and email the file for you.

Obviously there are tools like rsync and scp - but of your needs are specialized a Folder Action could be your cure.

If you need to SSH from a Windows machine download PuTTY. PuTTY’s single exe is a snap to use. You should probably have a copy on your thumb-drive for convenient access.

Using PuTTy isn’t exactly the same as running a Terminal session on your Mac. For instance, you can’t use rsync to copy files from the PC to the remote Mac. If transferring files is a pressing need you can take a look at PSFTP and PSCP.

Here are the posts with information relevant to the task:

• Folder Actions - How to email files by dropping them in a Finder folder.
• Chicken of the VNC - The screencast includes basic instructions for port forwarding.
• Remote Login with SSH - Running a secure Terminal session on a remote machine. Also - look at SSH Without a Password.
  
• Zip - Packaging multiple files into a single file.

With the information in those screencasts you can extend the power of Folder Actions to SSH. Murphy’s not saying you’ll want to use this to email files - it’s just an example to illustrate the possibilities.

Some readers have pointed out that an Automator Droplet might be more useful than Folder Actions for mailing files. But you can’t trigger the Droplet from an SSH session like you can with Folder Actions. The Droplet has its benefits, but so do Folder Actions.

Write Ransom Notes With AppleScript

The Crazy Message Text script comes with OS X so you can make some festive looking emails for birthdays or holidays. But the finished product conjures up images of letters cut from a magazine and taped to a piece of paper. Like a ransom note from a James Patterson novel.

The script is fairly self-explanatory but Murphy’s throwing in a screencast anyway, in case you’re away from your Mac. It’s quick, take a look.

You’ve got other scripts in your /Library/Scripts/Mail Scripts folder - give them a peek - maybe there’s something you could use.

Note: The script generates a multi-color message, not something like the image in this post. Click the image above to generate your own classic-style ransom note.

iTunes Twofer Double Shot Block Party

You’d think this soon after wrapping iTunes week we’d be done with iTunes. But there’s one more script to take a look at before we put the jukebox on the back burner for a while.

Do you remember the days before iTunes and iPods when you listened to Double Shot days on the radio? Block Parties with three or four songs in a row by the same group?

The Block Party script generates a somewhat random playlist that includes multiple songs by each included artist. How many songs? That’s up to you. How big is the list? You can specify a number of artists or a duration. The download includes a readme with more information, like how to change the name of the playlist the script creates.

The script comes from Doug’s AppleScripts for iTunes - a site we visited last week.

Murphy is feeling nostalgic for Double Shot Tuesdays on WMMR in Philadelphia. You?