Screenshot of AS-Rabbit 1.10
A command line program for encryption and decryption of files. The program uses a 512-bit Rabbit with a 256-bit IV . This is a modified variant of Rabbit, the original version uses a 128-bit key with a 64-bit IV. It is basically the same algorithm, but instead of substituting key and IV, a longer key and IV are used. It is worth noting that the last 256 bits of the key can rather be seen as seeding values.
This program has one additional parameter. This is "-DB" (Drop Blocks, that drops the first 256 blocks).
The program uses a key strengthening algorithm , this increases the security.
The program stores an encrypted checksum  of the original file, which is verified at decryption.
The program delivers an ErrorLevel code  which indicates success (0) or failure (1).
The speed is measured and the program will display the results for you when it's done.
Use the parameter "-NoPercent" to display the number of Bytes that has been processed instead of percent.
Speed Reference: Approximately 128 MB/sec. (Intel Core i3-9100) 
Important information: Save the downloaded program if you have information encrypted with it. I do not guarantee compatibility between different versions/revisions of the program.
> Download AS-Rabbit 1.10 (Zip, 525 kB)
Revision Date: 2021-05-10.
Unicode Support: Yes.
Program Type: Fully portable, x64.
Operating System(s): Windows 7 (SP1+), 8.1 and 10. (Also Windows Server 2012 R2 and 2016.)
Language(s): Only English.
 In this program, a 256-bit random IV is used, which is fetched from Microsoft Crypto API. (RANDOM.DLL / RANDOM-X86.DLL)
 The key strengthening algorithm is using SHA3-512 and executes 131,072 times. (KSA.DLL / KSA-X86.DLL)
 The encrypted checksum is a CRC-64-ECMA.
 The ErrorLevel code can be useful when calling from batch files or other programs.
 The speed reference is measured under good conditions, a fast disk and a pretty large file.
You can also download all in one Zip file, Console_Crypto.ZIP.
Copyright © 1998-2021, Andreas Jönsson. All rights reserved.