Get last bitcon block hash, setup genesis header without PoW (for now)

Cargo.toml

@@ -12,6 +12,7 @@ build = "src/build/build.rs"
 
 [workspace]
 members = ["api", "chain", "config", "core", "keychain", "p2p", "servers", "store", "util", "pool", "wallet"]
+exclude = ["etc/gen_gen"]
 
 [[bin]]
 name = "grin"

etc/gen_gen/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "grin_gen_gen"
+version = "0.0.1"
+edition = "2018"
+authors = ["Grin Developers <mimblewimble@lists.launchpad.net>"]
+description = "Utility to automate the generation of Grin's genesis block"
+license = "Apache-2.0"
+repository = "https://github.com/mimblewimble/grin"
+keywords = [ "crypto", "grin", "mimblewimble" ]
+readme = "README.md"
+
+[[bin]]
+name = "gen_gen"
+path = "src/bin/gen_gen.rs"
+
+[dependencies]
+chrono = "0.4.4"
+curl = "0.4.19"
+serde_json = "1"
+grin_core = "0.4.2"
+grin_chain = "0.4.2"
+grin_keychain = "0.4.2"
+grin_store = "0.4.2"
+grin_util = "0.4.2"

etc/gen_gen/README.md

@@ -0,0 +1,18 @@
+# Genesis Genesis
+
+This crate isn't strictly part of grin but allows the generation and release of a new Grin Genesis in an automated fashion. The process is the following:
+
+* Prepare a multisig output and kernel to use as coinbase. In the case of Grin mainnet, this is done and owned by the council treasurers. This can be down a few days prior.
+* Grab the latest bitcoin block hash from publicly available APIs.
+* Build a genesis block with the prepared coinbase and the bitcoin block hash as `prev_root`. The timestamp of the block is set to 30 min ahead to leave enough time to run a build and start a node.
+* Mine the block so we have at least a valid Cuckatoo Cycle. We don't require a given difficulty for that solution.
+* Finalize the block with the proof-of-work, setting a high-enough difficulty (to be agreed upon separately).
+* Commit the block information to github.
+* Tag version 1.0.0 (scary).
+
+N.B. This was written while listening to Genesis. Unfortunately, I'm not rich enough to do it while driving a Genesis. And that'd be dangerous.
+
+# Usage
+
+1. Build this crate.
+2. From its root run `./target/release/gen-gen --coinbase <file> --difficulty <u64> --tag <version>`

etc/gen_gen/src/bin/gen_gen.rs

@@ -0,0 +1,114 @@
+// Copyright 2018 The Grin Developers
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Main for building the genesis generation utility.
+
+use std::fs;
+use std::sync::Arc;
+
+use chrono::Duration;
+use chrono::prelude::Utc;
+use curl;
+use serde_json;
+
+use grin_chain as chain;
+use grin_core as core;
+use grin_store as store;
+use grin_util as util;
+
+use grin_keychain::{ExtKeychain, Keychain};
+
+static BCHAIN_INFO_URL: &str = "https://blockchain.info/latestblock";
+static BCYPHER_URL: &str = "https://api.blockcypher.com/v1/btc/main";
+static BCHAIR_URL: &str = "https://api.blockchair.com/bitcoin/blocks?limit=2";
+
+fn main() {
+	// get the latest bitcoin hash
+	let h1 = get_bchain_head();
+	let h2 = get_bcypher_head();
+	let h3 = get_bchair_head();
+	if h1 != h2 || h1 != h3 {
+		panic!("Bitcoin chain head is inconsistent, please retry.");
+	}
+	println!("Using bitcoin block hash {}", h1);
+
+	// build the basic parts of the genesis block header, perhaps some of this
+	// can be moved to core
+	let mut gen = core::genesis::genesis_main();
+	gen.header.timestamp = Utc::now() + Duration::minutes(30);
+	gen.header.prev_root = core::core::hash::Hash::from_hex(&h1).unwrap();
+	gen.header.pow.proof.edge_bits = 29;
+	println!("Built genesis:\n{:?}", gen);
+
+	// TODO get the proper keychain and/or raw coinbase
+	let keychain = ExtKeychain::from_random_seed().unwrap();
+	let key_id = ExtKeychain::derive_key_id(0, 1, 0, 0, 0);
+	let reward = core::libtx::reward::output(&keychain, &key_id, 0, 0).unwrap();
+	gen = gen.with_reward(reward.0, reward.1);
+
+	{
+		// setup a tmp chain to set block header roots
+		let tmp_chain = setup_chain(".grin.tmp", core::pow::mine_genesis_block().unwrap());
+		tmp_chain.set_txhashset_roots(&mut gen).unwrap();
+		gen.header.output_mmr_size = 1;
+		gen.header.kernel_mmr_size = 1;
+	}
+
+	// TODO mine a valid Cuckatoo29 solution
+	// TODO check again the bitcoin block to make sure it's not been orphaned
+	// TODO Commit genesis block info in git and tag
+}
+
+fn setup_chain(dir_name: &str, genesis: core::core::Block) -> chain::Chain {
+	util::init_test_logger();
+	let _ = fs::remove_dir_all(dir_name);
+	let verifier_cache = Arc::new(util::RwLock::new(core::core::verifier_cache::LruVerifierCache::new()));
+	let db_env = Arc::new(store::new_env(dir_name.to_string()));
+	chain::Chain::init(
+		dir_name.to_string(),
+		db_env,
+		Arc::new(chain::types::NoopAdapter {}),
+		genesis,
+		core::pow::verify_size,
+		verifier_cache,
+		false,
+	).unwrap()
+}
+
+fn get_bchain_head() -> String {
+	get_json(BCHAIN_INFO_URL)["hash"].as_str().unwrap().to_string()
+}
+
+fn get_bcypher_head() -> String {
+	get_json(BCYPHER_URL)["hash"].as_str().unwrap().to_string()
+}
+
+fn get_bchair_head() -> String {
+	get_json(BCHAIR_URL)["data"][0]["hash"].as_str().unwrap().to_string()
+}
+
+fn get_json(url: &str) -> serde_json::Value {
+	let mut body = Vec::new();
+	let mut easy = curl::easy::Easy::new();
+	easy.url(url).unwrap();
+	{
+		let mut transfer = easy.transfer();
+		transfer.write_function(|data| {
+			body.extend_from_slice(data);
+			Ok(data.len())
+		}).unwrap();
+		transfer.perform().unwrap();
+	}
+	serde_json::from_slice(&body).unwrap()
+}