Factland Certified Blockchain Verification

Instructions and tools to download and verify Factland certified blockchain data.

Quick Start TL;DR

Install nodejs: https://nodejs.org/en/download/

Clone the repsitory:

% git clone https://github.com/Factland/certified-blockchain-verification.git

verify::

% ./verify.sh B_2_0_fbaa85233700a8ed1795abe1b11ce7b78c102b953cab07871f49b3fefed40397

OSX

You may need to install git how to install git on a mac.

You may need to install xcode:

xcode-select --install

The Data

Factland data is stored on the Internet Computer in a canister smart contract:

• Production Canister ID: 6nlm3-giaaa-aaaae-qaepq-cai
• Staging Canister ID: 3nump-2aaaa-aaaae-qaesa-cai
• Source Code: https://github.com/Factland/ic-certified-blockchain.git
• Dashboard URL: https://dashboard.internetcomputer.org/canister/6nlm3-giaaa-aaaae-qaepq-cai

Each adjudicated claim is stored as JSON with fields:

• title The title of the claim that was adjudicated.
• text The text body of the claim that was adjudicated.
• date The date of the adjudicated.
• jurySize The size of the Jury that made the adjudication.
• ruling The ruling:
  • undecided The jury was unable to come to a decision.
  • true The jury ruled that the claim was true.
  • false The jury ruled that the claim was false.

Blocks

Factland data is stored in blockchain with each block containing a hash of the previous block and a set of entries. The record of each adjudication claim occupies a single entry of a block. Entries may be located by block and entry number or by a hash of the contents via a find function from hash to block number after which the entry can be found by linear search. The schema of the blockchain and the methods available on the canister smart contract are detailed in the API.

IC Blockchain Key

Each adjudicated claim has a key assocated with it which appears in the Factland app. The key has the form:

B_2_0_fbaa85233700a8ed1795abe1b11ce7b78c102b953cab07871f49b3fefed40397

where the B_ prefix indicates that this is a staging adjudicated claim, the 2_0_ indicates that the record of this claim is in block 2 entry 0. The suffix fbaa85233700a8ed1795abe1b11ce7b78c102b953cab07871f49b3fefed40397 is the hash (SHA256) of the record.

Block and Record Verification

The data is stored in blocks which are certified by the Internet Computer NNS public key via a delegation to the subnet and then the canister smart contract. This certification chain canister be verified offline by retriving the data and checking the signatures and Merkle tree of entry hashes.

Installation

The verification code is written in javascript for nodejs and requires a nodejs installation, download of this code and installation of the dependencies:

% git clone https://github.com/Factland/certified-blockchain-verification.git
% cd src
% npm i

Printing Blocks

Blocks can be printed (in the src directory) by executing:

% node print_block.js B0

This will produce output like:

{
  certificate: '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',
  tree: 'd9d9f78302506365727469666965645f626c6f636b73830183018301830244000000008203582005dd7c071fd74ee5eb03db998c402f14eb1b304a0778d7307c86599c9dcec16283018302440000000182035820d8f8743deafd50b221bb9db707b4e0d116c1c1a494b989ea684c63369bf596558302440000000282035820cb7e0d0cdc9329492e85aae26fcc57d1109dc85252f440ef1dff9af7ea639ac483018302440000000382035820c10796db92ccd2b846255ae8a8618625a04a7304346ec09ef13657742f932423830183024400000004820358201e6d6f88aff10c6a353e78f932f07b8ea8fbb24ef60b6d525ff471255921b046830183024400000005820358204c703f642fe228a210e12de68dc9cd7400822800b06dacd9ab05c2283bd0954b830244000000068203582006ffbda5446c54d214c2bc74e527a07497ee777cc69fff4391fc62f7e0c9aab583018302440000000782035820c2115e945cca2081ec3e6f83bb16716b1fa244659a51229b9a9679cd6ace53af83018301830244000000088203582040998bf1910e1d2751cdc1e6c48009d564ebbfe03b51edc59e8a2f3c22091855830183024400000009820358204c9e2378371353b5c33dd75c45c6112b32899a9764d06323aa570df70c5c0fab8302440000000a820358208248fdb4617d3ce77172874fe945d38e2abd84027652250ee3ae585b26e15f4a83018302440000000b8203582058a38588732eb6c01a599336c077daec4f6ddb63efa084e375e7578228d81b15830183018302440000000c82035820dcc8955b7f53054c7682314306784cc5c16014755e051a8026cd130c7bdde3e483018302440000000d82035820080bb8248d2219b608af41eb7ec1fc51e422005232de7cdc0edc1cc65b61897f8302440000000e82035820d2438644257a98a4d4fb01c12baba1990aa6f8cc62811fcfeb514b32395f200f83018302440000000f82035820ba0cca5fd48d7dafb4e9688ddbc3db85693b5e3f4d7fe3585a3147178a68d9cf83018302440000001082035820aaf5d33ca69e58aa364e9060f59f24476db1cabf0aa39d8b0ff1df70e459b7fc83024d70726576696f75735f68617368820358200000000000000000000000000000000000000000000000000000000000000000',
  data: [
   '{"title":"Changes now live on staging. Does it work?","text":"Bleep","date":"2023-01-17T22:03:04.905Z","jurySize":0,"ruling":"undecided"}',
   '{"title":"FAA network outage caused recent Bitcoin price spike","text":"Source of the claim: FOX News pundit Tucker Carlson.\\n\\nTheory: The FAA’s computer systems went down on January 11th reportedly due to a network outage caused by a corrupt file. Since then, the price of Bitcoin has jumped over 20%. Coincidence? Carlson doesn’t think so. He claims that the U.S government was secretly forced into paying a ransom using Bitcoin, causing the price to jump.\\n","date":"2023-02-02T20:59:04.790Z","jurySize":2,"ruling":"undecided"}',
   ],
   previous_hash: '0000000000000000000000000000000000000000000000000000000000000000'
}

The certificate is the signature chain from the Internet Computer NNS public key down to the root of the Merkle tree and includes the date of certification. The tree is a Merkle tree containing a map from entry index to entry hash (SHA256).

Verifiying Records

Records are verified by key, including block and entry numbers and hash:

% node verify.js B_2_0_fbaa85233700a8ed1795abe1b11ce7b78c102b953cab07871f49b3fefed40397

Correctly verfied blocks will report:

block and entry verified!