Cardano Improvement Proposals


CIP 1855 - Forging policy keys for HD Wallets

Contents

Abstract

This document describes how to derive forging policy keys used for minting/burning tokens.

Glossary

Term Definition
HD Hierarchical Deterministic, refers to wallets as described in BIP-0032.

Motivation

Overview

Forging tokens is derived from a script policy. The script policy includes hashes of keys needed to forge new tokens and must be witnessed by the keys with hashes listed.

Specification

HD Derivation

We consider the following HD derivation paths similarly to CIP-1852:

m / purpose' / coin_type' / policy_ix'
    

To associate policy keys to a wallet, we reserve however purpose=1855' to reserve for policy keys for forging tokens. The coin type remains coin_type=1815' to identify Ada as registered in SLIP-0044. We use a hardened index for each policy key as derivation is not needed.

We can summarize the various paths and their respective domain in the following table:

purpose coin_type policy_ix
1855' 1815' [2^31 .. 2^32-1]

Rationale

Examples

Backwards Compatibility

N/A (no preceding implementation or design).

Reference Implementation

None yet.

Related Work

Description Link
BIP-0032 - HD Wallets https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki
CIP-5 - Common Bech32 Prefixes https://github.com/cardano-foundation/CIPs/tree/master/CIP-0005
CIP-1852 - Cardano HD Wallets https://github.com/cardano-foundation/CIPs/tree/master/CIP-1852
A Formal Specification of the Cardano Ledger https://hydra.iohk.io/job/Cardano/cardano-ledger-specs/shelleyLedgerSpec/latest/download-by-type/doc-pdf/ledger-spec

Copyright

CC-BY-4.0