IsJack Tool

IsJack Tool is a comprehensive Rust terminal UI application for payment systems development and testing. It provides tools for JSON processing, ISO 8583 message handling, cryptographic key management, TLV/EMV parsing, and network simulation.

Features

• JSON Tools: Beautify and minify JSON data
• ISO 8583 Decoder: Parse and decode ISO 8583 financial messages (hex or raw format)
• TLV/EMV Parser: Decode EMV TLV structures including ARQC, AFL, and FCI
• Key Management: Cryptographic operations including:
  • KCV (Key Check Value) calculation
  • 3DES encryption/decryption
  • PIN block building and decryption
  • XOR operations for key XORing
  • Luhn/BIN validation
• Simulator: Network simulator for server/client testing with configurable framing
• Settlement: Batch settlement processing and reporting
• Multi-tab interface with keyboard-driven navigation and word-wrap support

Prerequisites

• Rust 1.74 or later
• Cargo

Build & Run

cd /home/asepimam/Documents/project/isjack_tool
cargo build --release
./target/release/isjack_tool

Usage Guide

JSON (F1)

Process JSON data with formatting and compression tools:

• Paste or type JSON into the input pane
• Press Space or use s to toggle beautify/minify mode
• Use n to load sample JSON data
• Output appears in the right pane with syntax highlighting

ISO 8583 (F2)

Decode financial transaction messages in ISO 8583 format:

• Paste hex-encoded ISO 8583 messages into the input pane
• Press Space to decode and analyze
• Use d to toggle between hex and raw display modes
• Field names and values are parsed and displayed with clear formatting

TLV/EMV (F3)

Parse EMV TLV-encoded EMV structures:

• Enter hex-encoded TLV data (ARQC, AFL, FCI, etc.)
• Press Space to decode tagged structures
• Supports nested TLV structures
• Use n to load EMV sample data (includes real ARQC and AFL examples)

Key Management (F4)

Perform cryptographic operations:

1. Use o to cycle through operations:
   • KCV: Calculate key check value from key hex
   • 3DES Enc: Encrypt data with 2-key or 3-key 3DES
   • 3DES Dec: Decrypt 3DES-encrypted data
   • PIN Build: Build ISO PIN block from PIN and PAN
   • PIN Decrypt: Decrypt encrypted PIN block with ZPK
   • XOR: XOR two hex values (for key component derivation)
   • Luhn/BIN: Validate card number with Luhn algorithm
2. Fill in required fields (labels shown at top)
3. Press Space to execute operation
4. Results appear in the output pane

Supported key sizes:

• Single DES: 8 bytes
• 2-key 3DES: 16 bytes
• 3-key 3DES: 24 bytes

Simulator (F5)

Network simulator for testing ISO 8583 message exchange:

• Use m to toggle between Server and Client modes
• Server mode: Start TCP listener on configured port
  • Press Space to start/stop the server
• Client mode: Send messages to remote server
  • Enter message in hex format
  • Press Space to send
  • Logs show SEND/RECV events
• Use f to cycle framing modes (binary/text)
• Use n to load sample client messages

Settlement (F6)

Process settlement batches and generate reports:

• Upload or paste CSV settlement data
• Parse and validate batch information
• Generate settlement reports with totals and summaries
• Press Space to process and generate output

Key Bindings

Global

Key	Action
F1	Switch to JSON tab
F2	Switch to ISO 8583 tab
F3	Switch to TLV/EMV tab
F4	Switch to Key Management tab
F5	Switch to Simulator tab
F6	Switch to Settlement tab
Tab	Switch focus between Input and Output panes
Ctrl+Q	Quit application
Ctrl+L	Clear input
Ctrl+W	Toggle word-wrap
Ctrl+A	Select all text
Ctrl+C	Copy output
Ctrl+X	Cut output

Navigation (in output pane)

Key	Action
↑↓	Scroll up/down
PgUp/PgDn	Page up/down
g	Jump to top
G	Jump to bottom

Tab-specific shortcuts

Tab	Key	Action
JSON	s	Cycle sample data
JSON	n	Load next sample
ISO 8583	d	Toggle display mode (hex/raw)
ISO 8583	n	Load next sample
TLV/EMV	n	Load next sample
Key Mgmt	o	Cycle operation (KCV/3DES/PIN/XOR/Luhn)
Key Mgmt	n	Load sample for current operation
Simulator	m	Toggle mode (Server/Client)
Simulator	f	Cycle framing mode
Simulator	n	Load client sample message
Settlement	r	Reload sample data

Input Formats

ISO 8583

Input must be a hex string representing the complete ISO 8583 message:

• MTI: 4 bytes (8 hex chars), e.g. 30323030 = 0200
• Primary bitmap: 8 bytes (16 hex chars)
• Secondary bitmap: 8 bytes (16 hex chars), if bit 1 is set
• Data fields: Follow bitmap order with TLV/LLVAR/LLLVAR length indicators as defined

Example: 30323030723800000080000031363441313131... (hex-encoded ASCII)

TLV/EMV

Input must be hex-encoded binary TLV data:

• Each tag is 1-3 bytes (tag format F in first nibble determines length)
• Length field indicates number of value bytes
• Value can contain nested TLV structures

Example: 9F2608A1B2C3D4E5F6A7829F2701809F... (EMV ARQC)

Key Management

Formats depend on the operation:

• Hex values: Uppercase or lowercase hex pairs, e.g. 0123456789ABCDEF
• PIN: 4-12 decimal digits only, e.g. 1234
• PAN: Card number with optional dashes, e.g. 4111-1111-1111-1111
• Key sizes: Exactly 8, 16, or 24 bytes (16, 32, or 48 hex chars)

Simulator

Two common formats supported:

• Binary: Raw binary data (shown as hex in input)
• ISO 8583 Hex: Hex-encoded ISO 8583 messages

Framing modes determine message boundaries in TCP streams.

Configuration

Simulator Settings

Default configuration:

• Server: Listens on 127.0.0.1:8583 (modifiable in-app)
• Framing: Binary2 format (supports binary, text, and other protocols)
• Mode: Toggle between Server and Client via m key

To connect an external client:

• Ensure server is running (green indicator in simulator tab)
• Connect to the configured host and port
• Send raw or ISO 8583 hex-encoded messages

Build Requirements

• Rust: 1.74 or later
• Dependencies: Cargo will automatically download ratatui, serde, crossterm, and other utilities

Note on ratatui version: The project uses ratatui 0.29.0 for Rust 1.74+ compatibility. To upgrade to ratatui 0.30.0, you'll need Rust 1.85+ (requires updating Cargo.toml).

Clipboard Operations

• Ctrl+C: Copy output pane to clipboard (non-blocking background thread)
• Ctrl+X: Cut output pane to clipboard
• Shift+Arrows: Select text in input pane
• Paste: Use terminal paste or Ctrl+Shift+V to insert content

Troubleshooting

Issue	Solution
Clipboard not working	Ensure arboard dependency is available on your system
Simulator connection refused	Check port is not in use: lsof -i :8583
TLV parsing errors	Verify hex data is valid; check tag format byte
3DES errors	Ensure key length is exactly 8, 16, or 24 bytes
PIN block mismatch	Verify PAN format (12-19 digits, no spaces) and PIN length (4-12 digits)

Built-in Sample Data

Each tab includes pre-loaded samples for quick testing:

• JSON: E-Commerce transaction, ISO 8583 field map, settlement batch, minimal JSON
• ISO 8583: Network management (0800) and purchase auth (0200) messages
• TLV/EMV: ARQC, AFL, FCI with PDOL, masked Track 2 data
• Key Mgmt: Sample keys (2-key 3DES, single DES, 3-key 3DES) and test PANs (Visa, Mastercard, Amex, BCA)
• Simulator: Network management (RAW) and purchase auth (HEX-encoded) client messages
• Settlement: Sample batch with debit/credit transactions and terminal configuration

Press n in any tab to load sample data.

Format Support

• JSON: Full JSON parsing with beautify (pretty-print) and minify (compact)
• ISO 8583: Fields up to 128 with configurable processing codes and data
• TLV/EMV: Nested tag structures, EMV cryptogram processing
• Keys: DES/3DES, AES-compatible hex values, variable-length keys
• Simulator: Binary and ISO 8583 HEX formats with multiple framing modes

Screenshots

ISO 8583

JSON

Key Management

Simulator

TLV/EMV

Settlement