CIP 1855 - Forging policy keys for HD Wallets
This document describes how to derive forging policy keys used for minting/burning tokens.
|HD||Hierarchical Deterministic, refers to wallets as described in BIP-0032.|
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.
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:
ERC20 Converter IOHK is developing needs to keep track of policy keys. Rather than having randomly generated policy keys, a policy key can be associated with a mnemonic which is easier to backup.
A 3rd party may want to have multiple tokens tied to same mnemonic, so we allow an index to specify the token.
We use a different purpose for mainly two reasons:
It prevents mixing up standard wallets with policy keys used for forging.
Using a different purpose also fits well the use-case on hardware wallets who can still rely on a single root seed to manage many types of wallets.
N/A (no preceding implementation or design).
|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|