LNPBP-81: Tagged Merkle trees

LNPBP: 0081
Vertical: Cryptographic primitives
Title: Tagged merkle trees for client-side-validation
Author: Dr Maxim Orlovsky  <[e-mail]>,
        Peter Todd
Comments-URI: https://github.com/LNP-BP/lnpbps/issues/<____>
Status: Draft
Type: Standards Track
Created: 2021-05-11
License: CC0-1.0

• Abstract

• Background

• Motivation

• Design

• Specification

• Compatibility

• Rationale

• Reference implementation

• Acknowledgements

• References

• Copyright

• Test vectors

Abstract

Background

Motivation

Problems with modern merkle trees:

• Depth extension attack: no commitment to the tree depth

Design

Based on bitcoin merklization with following modifications:

• Tagged hashing for source data

• Tagged hashing of each tree object

• Commitments to depth, width and height of the tree

• Custom placeholders for empty objects

• Restricting tree source to 2^16 elements (height is always <=16)

Specification

Compatibility

Rationale

Reference implementation

Acknowledgements

References

Copyright

This document is licensed under the Creative Commons CC0 1.0 Universal license.

Test vectors