Blockchain Transaction Verification via ECDSA r-Puzzle Challenge

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional hash puzzles in blockchain transactions are vulnerable to malicious miners who can observe the unlocking script and create a malleated version of the transaction, redirecting payments to themselves instead of the intended recipient, as they do not securely verify the knowledge of the data being redeemed.

Innovation Solution

The implementation of an r-puzzle framework using Elliptic Curve Digital Signature Algorithm (ECDSA) signatures, where the r-part of the signature is used to create a challenge that only the rightful prover can solve, ensuring that the knowledge of the challenge solution is proven without revealing the solution itself, thus preventing malicious redirections.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional hash puzzles are used in blockchain transactions, then transactions can be verified for basic validity, but malicious miners can observe the unlocking script and create malleated versions of transactions to redirect payments to themselves

Engineering Contradiction:
Improvetransaction verification reliabilityVSAvoidmalicious transaction redirection
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent introduces an intermediary verification mechanism using ECDSA signatures. Instead of directly verifying the unlocking script, the system uses the r-part of ECDSA signatures as an intermediary that proves knowledge of the challenge solution without revealing it. This intermediary layer prevents malicious miners from observing and malleating the actual solution data while still enabling verification.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the conventional hash puzzle mechanism with an ECDSA signature-based verification mechanism. Instead of relying on hash function properties, the system uses elliptic curve cryptography to prove knowledge of the challenge solution. This substitution eliminates the vulnerability to observation and malleation that exists in hash-based systems.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Ease of operation

If the challenge solution is revealed in the unlocking script, then verification is straightforward, but the solution can be observed and exploited by malicious miners

Engineering Contradiction:
Improveverification easeVSAvoidsolution confidentiality
Core Design Contradiction:
Ease of operationVSLoss of information

Solution Approach 1:

The patent converts the potential harm of revealing the solution into a benefit by using the r-part of ECDSA signatures. The r-value, which is normally just part of a signature, becomes a cryptographic proof of knowledge. This allows verification without revealing the actual challenge solution, turning what would be a security vulnerability into a security feature.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent changes the verification parameter from the challenge solution itself to the r-part of an ECDSA signature. This parameter change allows the system to verify knowledge of the solution without exposing the solution. The r-value serves as a transformed representation that maintains verification capability while eliminating information leakage.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3973661B1Knowledge proof
Publication Date: 2024.02.28 NCHAIN LICENSING AG
  • EP3973661B1 patent drawingFigure 1
  • EP3973661B1 patent drawingFigure 2
  • EP3973661B1 patent drawingFigure 3~4

AI summary

A knowledge proof is performed using a set of transactions for recording in a blockchain maintained in a blockchain network. A challengee receives a competition challenge. The competition challenge has a derivable challenge solution but the challenge solution is not communicated to the challengee directly. The challengee competes with one or more other challengees to derive an independent instance of the challenge solution from the competition challenge. Upon the challengee successfully deriving the independent instance of the challenge solution before any of the other one or more challengees, the challengee uses data thereof as a secret challengee key to sign at least one message, and thereby generate at least one transaction signature, and submits the at least one transaction signature and the at least one message to the blockchain network for verifying at a node of the blockchain network.