Get-RandomHex

Get-RandomHex.ps1 is a PowerShell script designed to generate cryptographically secure random hexadecimal strings. This is useful for creating keys, tokens, or any scenario where high-entropy random data is required. A common use case is generating a 16-byte (128-bit) key, which aligns with the recommended minimum entropy for session IDs as per OWASP guidelines.

Features

• Generates random hexadecimal strings based on a specified bit length.
• Utilizes cryptographically secure random number generation methods.
• Compatible with multiple .NET versions due to the use of RandomNumberGenerator.Create().
• Accepts the -BitLength parameter at both the script and function levels.
• Handles bit lengths not divisible by 8 by appropriately trimming the output.

Usage

Running the Script Directly

To generate a hex string without specifying a bit length (defaults to 256 bits):

.\Get-RandomHex.ps1

To generate a hex string in PowerShell based on a desired bit length:

.\Get-RandomHex.ps1 -BitLength 128

Importing the Function into Your Session

You can import the function and use it directly in your PowerShell session:

• Import the function

. .\Get-RandomHex.ps1

• Generate a 256-bit random hexadecimal string

Get-RandomHexString

• Generate a 128-bit random hexadecimal string

Get-RandomHexString -BitLength 128

Installation

1. Clone or download this repository to your local machine.
2. Run the script directly or import the function into your PowerShell session.
   • Running the script directly:

   .\Get-RandomHex.ps1

   • Importing the function:

   . .\Get-RandomHex.ps1  # Note the dot and space before the script path

Contribution

Contributions are welcome! Please open an issue or submit a pull request for any improvements or fixes. Before submitting a PR, ensure that you've tested your changes and updated any necessary documentation.