ECIP-1044: Formalize IPFS hash into ECNS resolver

[PhyrexTsai]

Title

ECIP: 1044
Title: Formalize IPFS hash into ECNS resolver
Author: Phyrex Tsai <phyrex@portal.network>, Portal Network Team
Status: Draft
Type: ERC
Created: 2018-05-12

ECIP 1044 - Formalize IPFS hash into ECNS(Ethereum Classic Name Service) resolver

Simple Summary

To specify the mapping protocol between resources stored on IPFS and ECNS(Ethereum Classic Name Service).

Abstract

The following standard details the implementation of how to combine the IPFS cryptographic hash unique fingerprint with ecns public resolver. This standard provides a functionality to get and set IPFS online resources to ecns resolver.

We think that this implementation is not only aim to let more developers and communities to provide more use cases, but also leverage the human-readable features to gain more user adoption accessing decentralized resources. We considered the IPFS ecns resolver mapping standard a cornerstone for building future Web3.0 service.

Motivation

To build fully decentralized web service, it’s necessary to have a decentralized file storage system. Here comes the IPFS, for three following advantages :

• Address large amounts of data, and has unique cryptographic hash for every record.
• Since IPFS is also based on peer to peer network, it can be really helpful to deliver large amounts of data to users, with safer way and lower the millions of cost for the bandwidth.
• IPFS stores files in high efficient way via tracking version history for every file, and removing the duplications across the network.

Those features makes perfect match for integrating into ecns, and these make users can easily access content through ecns, and show up in the normal browser.

Specification

The condition now is that the IPFS file fingerprint using base58 and in the meantime, the Ethereum Classic uses hex in API to encode the binary data. So that need a way to process the condition requires not only we need to transfer from IPFS to Ethereum Classic, but also need to convert it back.

To solve these requirements, we can use binary buffer bridging that gap.
When mapping the IPFS base58 string to ecns resolver, first we convert the Base58 to binary buffer, turn the buffer to hex encrypted format, and save to the contract. Once we want to get the IPFS resources address represented by the specific ecns, we can first find the mapping information stored as hex format before, extract the hex format to binary buffer, and finally turn that to IPFS Base58 address string.

Rationale

To implement the specification, need two methods from ecns public resolver contract, when we want to store IPFS file fingerprint to contract, convert the Base58 string identifier to the hex format and invoke the setMultihash method below :

function setMultihash(bytes32 node, bytes hash) public only_owner(node);

Whenever users need to visit the ecns content, we call the multihash method to get the IPFS hex data, transfer to the Base58 format, and return the IPFS resources to use.

function multihash(bytes32 node) public view returns (bytes);

Test Cases

To implement the way to transfer from base58 to hex format and the reverse one, using the ‘multihashes’ library to deal with the problem.
The library link : https://www.npmjs.com/package/multihashes
To implement the method transfer from IPFS(Base58) to hex format :

import multihash from 'multihashes'

export const toHex = function(ipfsHash) {
  let buf = multihash.fromB58String(ipfsHash);
  return '0x' + multihash.toHexString(buf);
}

To implement the method transfer from hex format to IPFS(Base58) :

import multihash from 'multihashes'

export const toBase58 = function(contentHash) {
  let hex = contentHash.substring(2)
  let buf = multihash.fromHexString(hex);
  return multihash.toB58String(buf);
}

Implementation

The use case can be implemented as browser extension. Users can easily download the extension, and easily get decentralized resources by just typing the ECNS just like we normally type the DNS to browser the website. Solve the current pain for normal people can not easily visit the total decentralized website.

The workable implementation repository : https://github.com/PortalNetwork/portal-network-browser-extension

Copyright

Copyright and related rights waived via CC0.

[Dexaran]

Currently, ECNS contract deos not support the MultiHash functionality. At the time of ECNS creation it was not yet implemented at ENS. Then there were no demand on ECNS upgrades.

However, I'm ready to upgrade the Public Resolver if necessary.

[Dexaran]

You can find current Public Resolver source code here: https://github.com/EthereumCommonwealth/ECNS/blob/master/PublicResolver.sol

[PhyrexTsai]

Otherwise can we use setContent and content instead

[Dexaran]

content is of bytes32 type. multihash is dynamic length bytes. If this is not an issue then you can definitely use content.

[PhyrexTsai]

content for IPFS and Swarm hash is not an issue now, if we do consider for future usage it is better use bytes and implement a method support multihash

[PhyrexTsai]

I also submit a Pull Request for ECNS to support multihash and setMultihash for future usage. https://github.com/EthereumCommonwealth/ECNS/pull/3

[Dexaran]

This requires ECNS public resolver to be redeployed though.