If you want operating system independence, e.g., a thumb drive that you can use on systems other than macOS, you might want to look at VeraCrypt - the successor to TrueCrypt. VeraCrypt is open source as well. Further information can be found in Encrypt FAT USB drive under El Capitan. truecrypt is not exactly 'open source', but the source is available. See the reviews to get more information. truecrypt is a disk encryption software for windows vista/xp, mac os x, and linux.creates a virtual encrypted disk within a file and mounts it as a real disk. 7.1a February 7, 2012 Improvements and bug fixes: Minor improvements and bug fixes (Windows, Mac OS X, and Linux) 7.1 September 1, 2011 New features: Full compatibility with 64-bit and 32-bit Mac OS X 10.7 Lion Improvements and bug fixes: Minor improvements and bug fixes (Windows, Mac OS X, and Linux) 7.0a September 6, 2010. TrueCrypt for Mac. TrueCrypt was a free and open-source disk encryption utility first launched in 2004. It can create a virtual encrypted disk within a file, or encrypt a partition or the whole storage device. If you have files encrypted by TrueCrypt on Mac OS X: Open Utilities in Applications:; Open Disk Utility in Utilities:; Click New Image icon. Select Size according to the size of data encrypted by TrueCrypt and select Encryption.Then click Create to create a new encrypted virtual disk file:; Copy all data encrypted by TrueCrypt to the new encrypted disk which should be mounted now.
7.1a
Improvements and bug fixes:
- Minor improvements and bug fixes (Windows, Mac OS X, and Linux)
7.1
New features:
- Full compatibility with 64-bit and 32-bit Mac OS X 10.7 Lion
Improvements and bug fixes:
- Minor improvements and bug fixes (Windows, Mac OS X, and Linux)
7.0a
Improvements:
- Workaround for a bug in some custom (non-Microsoft) drivers for storage device controllers that caused a system crash when initiating hibernation on TrueCrypt-encrypted operating systems. (Windows 7/Vista/2008/2008R2)
- Other minor improvements (Windows, Mac OS X, and Linux)
Bug fixes:
7.0
New features:
- Hardware-accelerated AES (for more information, see the chapter Hardware Acceleration).Note: If you want to disable hardware acceleration, select Settings > Performance and disable the option ‘Accelerate AES encryption/decryption by using the AES instructions of the processor‘.
- A volume can now be configured to be automatically mounted whenever its host device gets connected to the computer (provided that the correct password and/or keyfiles are supplied). (Windows)Note: For example, if you have a TrueCrypt container on a USB flash drive and you want to configure TrueCrypt to mount it automatically whenever you insert the USB flash drive into the USB port, follow these steps: 1. Mount the volume. 2. Right-click the mounted volume in the drive list in the main TrueCrypt window and select ‘Add to Favorites‘. 3. The Favorites Organizer window should appear. In it, enable the option ‘Mount selected volume when its host device gets connected‘ and click OK.
Also note that TrueCrypt will not prompt you for a password if you have enabled caching of the pre-boot authentication password (Settings > ‘System Encryption‘) and the volume uses the same password as the system partition/drive. The same applies to cached non-system volume passwords.
- Partition/device-hosted volumes can now be created on drives that use a sector size of 4096, 2048, or 1024 bytes (Windows, Linux). Note: Previously only file-hosted volumes were supported on such drives.
- Favorite Volumes Organizer (Favorites > ‘Organize Favorite Volumes‘ or ‘Organize System Favorite Volumes‘), which allows you to set various options for each favorite volume. For example, any of them can be mounted upon logon, as read-only or removable medium, can be assigned a special label (which is shown within the user interface instead of the volume path), excluded from hotkey mount, etc. The order in which favorite volumes are displayed in the Favorites Organizer window can be changed and it is the order in which the volumes are mounted (e.g. when Windows starts or by pressing the ‘Mount Favorite Volumes‘ hotkey). For more information, see the chapters Favorite Volumes and System Favorite Volumes. (Windows)
- The Favorites menu now contains a list of your non-system favorite volumes. When you select a volume from the list, you are asked for its password (and/or keyfiles) (unless it is cached) and if it is correct, the volume is mounted. (Windows)
Security improvements:
- In response to our public complaint regarding the missing API for encryption of Windows hibernation files, Microsoft began providing a public API for encryption of hibernation files on Windows Vista and later versions of Windows (for more information, see the section TrueCrypt 5.1a in this version history). Starting with this version 7.0, TrueCrypt uses this API to encrypt hibernation and crash dump files in a safe documented way. (Windows 7/Vista/2008/2008R2)Note: As Windows XP and Windows 2003 do not provide any API for encryption of hibernation files, TrueCrypt has to modify undocumented components of Windows XP/2003 in order to allow users to encrypt hibernation files. Therefore, TrueCrypt cannot guarantee that Windows XP/2003 hibernation files will always be encrypted. Therefore, if you use Windows XP/2003 and want the hibernation file to be safely encrypted, we strongly recommend that you upgrade to Windows Vista or later and to TrueCrypt 7.0 or later. For more information, see the section Hibernation File.
Improvements:
- Many minor improvements. (Windows, Mac OS X, and Linux)
Bug fixes:
Removed features:
- TrueCrypt no longer supports device-hosted volumes located on floppy disks. Note: You can still create file-hosted TrueCrypt volumes on floppy disks.
6.3a
Improvements and bug fixes:
- Minor improvements and bug fixes. (Windows, Mac OS X, and Linux)
6.3
New features:
- Full support for Windows 7.
- The ability to configure selected volumes as ‘system favorite volumes’. This is useful, for example, when you have volumes that need to be mounted before system and application services start and before users start logging on. It is also useful when there are network-shared folders located on a TrueCrypt volume and you need to ensure that the network shares will be restored by the system each time it is restarted. For more information, see the chapter System Favorite Volumes. (Windows)
Improvements and bug fixes:
- ‘Favorite’ volumes residing within partitions or dynamic volumes will no longer be affected by changes in disk device numbers, which may occur, e.g., when a drive is removed or added. Note: If you use a favorite volume list saved by TrueCrypt 6.2a or earlier and you want to take advantage of this improvement, you need to resave the list using TrueCrypt 6.3. (Windows)
- Many other minor improvements and bug fixes. (Windows, Mac OS X, and Linux)
The development of TrueCrypt was ended in 5/2014 after Microsoft terminated support of Windows XP. Windows 8/7/Vista and later offer integrated support for encrypted disks and virtual disk images. Such integrated support is also available on other platforms (click here for more information). You should migrate any data encrypted by TrueCrypt to encrypted disks or virtual disk images supported on your platform.
For summary see the following web site 'TRUECRYPT: WHAT HAPPENED? WHO CARES? WHAT’S NEXT?'
By: David Adams, University of Utah - Revised: 2014-01-23 richardView Streamed Video
Introduction
TrueCrypt for Mac OS X - by Dave Adams, University of Utah
Dave discussed the pros and cons of TrueCrypt for Mac OS X and demonstration on its use.
TrueCrypt
Is a free open-source disk encryption software for Windows Vista/XP, Mac OS X, and Linux. It supports on-the-fly-encryption (OTFE) and it can create a 'file-hosted container' or write a partition which consists of an encrypted volume with its own file system, contained within a regular file, which can then be mounted as if it were a real disk. It supports encryption algorithms: AES-256, Serpent, and Twofish. And mode of operation: XTS.
The Mac OS X version uses MacFUSE to provide user-mode mounting of the encrypted disk. The main application window gives you a simple interface for creating and mounting encrypted images.
Update
The development of TrueCrypt was ended in 5/2014 after Microsoft terminated support of Windows XP. Windows 8/7/Vista and later offer integrated support for encrypted disks and virtual disk images. Such integrated support is also available on other platforms (click here for more information). You should migrate any data encrypted by TrueCrypt to encrypted disks or virtual disk images supported on your platform.
WARNING: Using TrueCrypt is not secure as it may contain unfixed security issues.
For summary see the following web site: