Product Delivery Protocol in OCaml

Product Delivery Protocol is a network protocol that simulates a blockchain smart contrat. A client can purchase products using their crypto money.

The program is written in OCaml language and the protocol is carried out through network communication using TCP/IP.

The Sodium library is used for the signatures and encryptions.

Architecture

Server

• PDP_server.ml:

  • Introduce the program
  • Establish connexion with 5 possible clients at the same time.
  • Send welcome message
  • Signature with Sodium library

• data_managment.ml:

  • Encryption of data using Sodium library
  • Send encrypted product

• product.ml:

  • Product class: price, name, description, data, data crypted, contract address, secret key and public key.
  • Product methods
  • Generate product
  • Process user requests
    • Send product name
    • Send product data
    • Send product description
    • Send product price
    • Send product contract address

• client.ml:

  • Client class: name, address, signed proof
  • Client methods
  • Send an offer for a product

Client

• PDP_client.ml:

  • Establish connexion with the server
  • Retry establishment of connexion if failed
  • Retrieve products names availables on the server
  • Asks if user want to procede with the purchase
  • Send refusal of offer to server

• PDP_purchase.ml:

  • Product to purchase class and its methods
  • Blockchain Tezos informations and methods
    • Client signature
    • Client address
    • Server signature
    • Contract address
    • Client name
  • Procede with the purchase steps
    • Send request for specific product
    • Send money
    • Decrypt the product

• PDP_conversion.ml:

  • conversion between strings, hex, string to word array...