X Client Transaction ID Generator

A C# library for generating cryptographic transaction IDs used by the X (formerly Twitter) web client. This library extracts and processes animation data and cryptographic keys from X's homepage to generate valid transaction identifiers.

Features

• Extracts cryptographic keys from X homepage HTML
• Processes animation frame data for transaction generation
• Generates SHA256-based transaction IDs with XOR encryption
• Supports both direct usage and factory pattern initialization

Prerequisites

• .NET 8.0 or later
• HtmlAgilityPack NuGet package

Installation

1. Clone this repository:

git clone <repository-url>
cd cs-x-client-transaction-id

2. Restore dependencies:

dotnet restore

3. Build the project:

dotnet build

Usage

Basic Usage

using HtmlAgilityPack;
using XClientTransactionId;

// Load X homepage HTML
var document = new HtmlDocument();
document.LoadHtml(htmlContent);

// Create and initialize ClientTransaction
var transaction = new ClientTransaction(document);
await transaction.InitializeAsync();

// Generate transaction ID
string transactionId = await transaction.GenerateTransactionIdAsync(
    method: "POST",
    path: "/api/endpoint"
);

Console.WriteLine(transactionId);

Factory Pattern

// Using the factory method for one-step initialization
var transaction = await ClientTransaction.CreateAsync(document);
string transactionId = await transaction.GenerateTransactionIdAsync("POST", "/api/endpoint");

Advanced Usage

// Generate transaction ID with custom parameters
string transactionId = await transaction.GenerateTransactionIdAsync(
    method: "GET",
    path: "/api/users/lookup",
    response: customDocument,      // Optional: custom HTML document
    key: customKey,               // Optional: custom base64 key
    animationKey: customAnimKey,  // Optional: custom animation key
    timeNow: customTimestamp      // Optional: custom timestamp
);

Command Line Usage

The included Program.cs provides a command-line interface:

# Requires x.com.html file in parent directory
dotnet run "/api/endpoint"

How It Works

1. Key Extraction: Extracts base64-encoded key from the twitter-site-verification meta tag
2. Animation Data: Fetches and processes animation frame data from X's ondemand JavaScript files
3. Cryptographic Processing:
   • Combines HTTP method, path, timestamp, and animation data
   • Generates SHA256 hash of the combined data
   • XOR encrypts the result with extracted keys
   • Encodes as base64 string

API Reference

ClientTransaction Class

Constructor

• ClientTransaction(HtmlDocument homePageDocument) - Creates a new instance

Methods

• InitializeAsync() - Initializes the instance with extracted keys and animation data
• CreateAsync(HtmlDocument) - Static factory method that creates and initializes an instance
• GenerateTransactionIdAsync(string method, string path, ...) - Generates a transaction ID

Parameters for GenerateTransactionIdAsync

• method (required) - HTTP method (e.g., "GET", "POST")
• path (required) - API endpoint path
• response (optional) - Custom HTML document
• key (optional) - Custom base64 key
• animationKey (optional) - Custom animation key
• timeNow (optional) - Custom timestamp

Error Handling

The library throws exceptions for various error conditions:

• Missing or invalid HTML document
• Network errors when fetching ondemand files
• Missing cryptographic keys or animation data
• Uninitialized instance usage

Wrap method calls in try-catch blocks for proper error handling:

try
{
    var transaction = await ClientTransaction.CreateAsync(document);
    var id = await transaction.GenerateTransactionIdAsync("POST", "/api/endpoint");
}
catch (Exception ex)
{
    Console.WriteLine($"Error: {ex.Message}");
}

Dependencies

• HtmlAgilityPack (v1.11.54) - HTML parsing and manipulation
• .NET 8.0 - Target framework
• System.Security.Cryptography - SHA256 hashing
• System.Net.Http - HTTP client for fetching ondemand files

License

This project is provided as-is for educational and research purposes.