Cryptography
Welcome to the Cryptography module. This note will guide you thru all the methodologies that I used while preparing for the CEH (Practical) exam.
Introduction
Cryptography is the science of protecting information by transforming it into a secure format. This process, called encryption, has been used for centuries to prevent handwritten messages from being read by unintended recipients. Today, cryptography is used to protect digital data. It is a division of computer science that focuses on transforming data into formats that cannot be recognized by unauthorized users.
An example of basic cryptography is an encrypted message in which letters are replaced with other characters. To decode the encrypted contents, you would need a grid or table that defines how the letters are transposed.
For example, the translation grid below could be used to decode "aHR0cHM6Ly90aGVndXJ1c2VjLmNvbS8" as "https://thegurusec.com".
Tools
Calculate One-way Hashes using HashClac
You may use this tool to calculate the MD5 hashes
Calculate MD5 Hashes using MD5 Calculator
Use this tool to compare the hashes with other hashes
Calculate MD5 hashes for files using HashMyFiles
HashMyFiles is a small utility that allows you to calculate the MD5 and SHA1 hashes of one or more files in your system.
Perform File and Text Message Encryption using CryptoForge
Perform File Encryption using Advanced Encryption Package
Encrypt and Decrypt messages using BCText Encoder
Perform Disk Encryption Using VeraCrypt
VeraCrypt is an open-source utility for on-the-fly encryption. The software can create a virtual encrypted disk that works just like a regular disk but within a file. It can also encrypt a partition or the entire storage device with pre-boot authentication. VeraCrypt is a fork of the discontinued TrueCrypt project
Creating an encrypted VeraCrypt volume File
Open the application and click “Create Volume”.
tap on “Create an Encrypted File Container”.
Select a path where the volume has to be saved.
Now, mention the volume size.
Set a password for the encrypted volume file.
For file system format we can set as “FAT“ and cluster as “Default”.
Mounting the Encrypted file into a Volume
Select any volume of your choice.
Select the VeraCrypt volume created before to be added.
Select Mount and it may prompt for a password.
Uploading Files into VeraCrypt Virtual Encrypted Volume
Create/Copy/Move the files into the Volume which you choose for mounting.
Paste all your confidential files inside that virtual volume.
Once completed, open the VeraCrypt application and then press “Dismount”.
Bitlocker
BitLocker Drive Encryption is a data protection feature that integrates with the operating system and addresses the threats of data theft or exposure from lost, stolen, or inappropriately decommissioned computers.
BitLocker provides the most protection when used with a Trusted Platform Module (TPM) version 1.2 or later. The TPM is a hardware component installed in many newer computers by the computer manufacturers. It works with BitLocker to help protect user data and to ensure that a computer has not been tampered with while the system was offline.
Rohos Disk Encryption
Cryptool
CrypTool is an open-source project that is a free e-learning software for illustrating cryptographic and cryptanalytic concepts. According to "Hakin9", CrypTool is worldwide the most widespread e-learning software in the field of cryptology. CrypTool implements more than 400 algorithms.
I strongly recommend you learn all these tools. At least Go through the tools.
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