/* This file is part of DarkFi (https://dark.fi) * * Copyright (C) 2020-2023 Dyne.org foundation * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see . */ use std::{ collections::HashMap, path::{Path, PathBuf}, str::FromStr, }; use async_std::{ stream::StreamExt, sync::{Arc, Mutex, RwLock}, task, }; use async_trait::async_trait; use chrono::Utc; use darkfi::{ runtime::vm_runtime::SMART_CONTRACT_ZKAS_DB_NAME, tx::Transaction, zk::{halo2::Field, proof::ProvingKey, vm::ZkCircuit, vm_stack::empty_witnesses}, zkas::ZkBinary, }; use darkfi_money_contract::{ client::{ transfer_v1::TransferCallBuilder, MONEY_KEYS_COL_IS_DEFAULT, MONEY_KEYS_COL_PUBLIC, MONEY_KEYS_COL_SECRET, MONEY_KEYS_TABLE, MONEY_TREE_COL_TREE, MONEY_TREE_TABLE, }, MoneyFunction::TransferV1 as MoneyTransfer, MONEY_CONTRACT_ZKAS_BURN_NS_V1, MONEY_CONTRACT_ZKAS_MINT_NS_V1, }; use darkfi_sdk::{ crypto::{ constants::MERKLE_DEPTH, contract_id::MONEY_CONTRACT_ID, Keypair, MerkleNode, PublicKey, DARK_TOKEN_ID, }, incrementalmerkletree::bridgetree::BridgeTree, pasta::{group::ff::PrimeField, pallas}, tx::ContractCall, }; use darkfi_serial::{deserialize, serialize, Encodable}; use log::{debug, error, info}; use rand::rngs::OsRng; use serde_json::{json, Value}; use signal_hook::consts::{SIGHUP, SIGINT, SIGQUIT, SIGTERM}; use signal_hook_async_std::Signals; use sqlx::Row; use structopt_toml::{serde::Deserialize, structopt::StructOpt, StructOptToml}; use url::Url; use darkfi::{ async_daemonize, cli_desc, consensus::{ constants::{ MAINNET_BOOTSTRAP_TIMESTAMP, MAINNET_GENESIS_HASH_BYTES, MAINNET_GENESIS_TIMESTAMP, MAINNET_INITIAL_DISTRIBUTION, TESTNET_BOOTSTRAP_TIMESTAMP, TESTNET_GENESIS_HASH_BYTES, TESTNET_GENESIS_TIMESTAMP, TESTNET_INITIAL_DISTRIBUTION, }, proto::{ProtocolSync, ProtocolTx}, task::block_sync_task, ValidatorState, ValidatorStatePtr, }, net, net::P2pPtr, rpc::{ jsonrpc::{ ErrorCode::{InternalError, InvalidParams, MethodNotFound}, JsonError, JsonRequest, JsonResponse, JsonResult, }, server::{listen_and_serve, RequestHandler}, }, util::{ async_util::sleep, parse::decode_base10, path::{expand_path, get_config_path}, }, wallet::{walletdb::init_wallet, WalletPtr}, Error, Result, }; mod error; use error::{server_error, RpcError}; const CONFIG_FILE: &str = "faucetd_config.toml"; const CONFIG_FILE_CONTENTS: &str = include_str!("../faucetd_config.toml"); #[derive(Clone, Debug, Deserialize, StructOpt, StructOptToml)] #[serde(default)] #[structopt(name = "faucetd", about = cli_desc!())] struct Args { #[structopt(short, long)] /// Configuration file to use config: Option, #[structopt(long, default_value = "testnet")] /// Chain to use (testnet, mainnet) chain: String, #[structopt(long, default_value = "~/.config/darkfi/faucetd_wallet.db")] /// Path to wallet database wallet_path: String, #[structopt(long, default_value = "changeme")] /// Password for the wallet database wallet_pass: String, #[structopt(long, default_value = "~/.config/darkfi/faucetd_blockchain")] /// Path to blockchain database database: String, #[structopt(long, default_value = "tcp://127.0.0.1:9340")] /// JSON-RPC listen URL rpc_listen: Url, #[structopt(long)] /// P2P accept addresses for the syncing protocol sync_p2p_accept: Vec, #[structopt(long)] /// P2P external addresses for the syncing protocol sync_p2p_external: Vec, #[structopt(long, default_value = "8")] /// Connection slots for the syncing protocol sync_slots: u32, #[structopt(long)] /// Connect to seed for the syncing protocol (repeatable flag) sync_p2p_seed: Vec, #[structopt(long)] /// Connect to peer for the syncing protocol (repeatable flag) sync_p2p_peer: Vec, #[structopt(long)] /// Prefered transports of outbound connections for the syncing protocol (repeatable flag) sync_p2p_transports: Vec, #[structopt(long)] /// Enable localnet hosts localnet: bool, #[structopt(long)] /// Enable channel log channel_log: bool, #[structopt(long)] /// Whitelisted cashier address (repeatable flag) cashier_pub: Vec, #[structopt(long)] /// Whitelisted faucet address (repeatable flag) faucet_pub: Vec, #[structopt(long, default_value = "600")] /// Airdrop timeout limit in seconds airdrop_timeout: i64, #[structopt(long, default_value = "10")] /// Airdrop amount limit airdrop_limit: String, // We convert this to u64 with decode_base10 #[structopt(short, parse(from_occurrences))] /// Increase verbosity (-vvv supported) verbose: u8, } type ProvingKeyMap = Arc>>>; pub struct Faucetd { synced: Mutex, // AtomicBool is weird in Arc sync_p2p: P2pPtr, validator_state: ValidatorStatePtr, keypair: Keypair, _wallet: WalletPtr, merkle_tree: BridgeTree, airdrop_timeout: i64, airdrop_limit: u64, airdrop_map: Arc>>, proving_keys: ProvingKeyMap, } #[async_trait] impl RequestHandler for Faucetd { async fn handle_request(&self, req: JsonRequest) -> JsonResult { if !req.params.is_array() { return JsonError::new(InvalidParams, None, req.id).into() } let params = req.params.as_array().unwrap(); match req.method.as_str() { Some("airdrop") => return self.airdrop(req.id, params).await, Some(_) | None => return JsonError::new(MethodNotFound, None, req.id).into(), } } } impl Faucetd { pub async fn new( validator_state: ValidatorStatePtr, sync_p2p: P2pPtr, wallet: WalletPtr, timeout: i64, limit: u64, ) -> Result { // Here we initialize the wallet for the money contract. let merkle_tree = Self::initialize_wallet(wallet.clone()).await?; // This is kinda bad, but whatever. The hashmaps hold proving keys for // the money contract. We keep it under RwLock in case we want to add // other proving keys to it later. let proving_keys = Arc::new(RwLock::new(HashMap::new())); // For now we'll create the keys for the money contract let cid = *MONEY_CONTRACT_ID; // Do a lookup for the money contract's zkas database and fetch the circuits. let blockchain = { validator_state.read().await.blockchain.clone() }; let db_handle = blockchain.contracts.lookup(&blockchain.sled_db, &cid, SMART_CONTRACT_ZKAS_DB_NAME)?; let Some(mint_zkbytes) = db_handle.get(serialize(&MONEY_CONTRACT_ZKAS_MINT_NS_V1))? else { error!("{} zkas bincode not found in sled database", MONEY_CONTRACT_ZKAS_MINT_NS_V1); return Err(Error::ZkasBincodeNotFound); }; let Some(burn_zkbytes) = db_handle.get(serialize(&MONEY_CONTRACT_ZKAS_BURN_NS_V1))? else { error!("{} zkas bincode not found in sled database", MONEY_CONTRACT_ZKAS_BURN_NS_V1); return Err(Error::ZkasBincodeNotFound); }; let (mint_zkbin, _): (Vec, Vec) = deserialize(&mint_zkbytes)?; let (burn_zkbin, _): (Vec, Vec) = deserialize(&burn_zkbytes)?; let k = 13; let mint_zkbin = ZkBinary::decode(&mint_zkbin)?; let mint_circuit = ZkCircuit::new(empty_witnesses(&mint_zkbin), mint_zkbin.clone()); let burn_zkbin = ZkBinary::decode(&burn_zkbin)?; let burn_circuit = ZkCircuit::new(empty_witnesses(&burn_zkbin), burn_zkbin.clone()); info!("Creating mint circuit proving key"); let mint_provingkey = ProvingKey::build(k, &mint_circuit); info!("Creating burn circuit proving key"); let burn_provingkey = ProvingKey::build(k, &burn_circuit); { let provingkeys = vec![ (MONEY_CONTRACT_ZKAS_MINT_NS_V1.to_string(), mint_provingkey, mint_zkbin), (MONEY_CONTRACT_ZKAS_BURN_NS_V1.to_string(), burn_provingkey, burn_zkbin), ]; let mut proving_keys_w = proving_keys.write().await; proving_keys_w.insert(cid.inner().to_repr(), provingkeys); } // Get or create an initial keypair for signing transactions let keypair = Self::initialize_keypair(wallet.clone()).await?; info!("Faucet pubkey: {}", keypair.public); let faucetd = Self { synced: Mutex::new(false), sync_p2p, validator_state, keypair, _wallet: wallet, merkle_tree, airdrop_timeout: timeout, airdrop_limit: limit, airdrop_map: Arc::new(Mutex::new(HashMap::new())), proving_keys, }; Ok(faucetd) } async fn initialize_wallet(wallet: WalletPtr) -> Result> { // Perform wallet initialization for the money contract let wallet_schema = include_str!("../../../src/contract/money/wallet.sql"); // Get a wallet connection info!("Acquiring wallet connection"); let mut conn = wallet.conn.acquire().await?; info!("Initializing wallet schema"); sqlx::query(wallet_schema).execute(&mut conn).await?; let query = format!("SELECT * FROM {}", MONEY_TREE_COL_TREE); let merkle_tree = match sqlx::query(&query).fetch_one(&mut conn).await { Ok(t) => { info!("Merkle tree already exists"); deserialize(t.get(MONEY_TREE_COL_TREE))? } Err(_) => { let tree = BridgeTree::::new(100); let tree_bytes = serialize(&tree); let query = format!( "DELETE FROM {}; INSERT INTO {} ({}) VALUES (?1)", MONEY_TREE_TABLE, MONEY_TREE_TABLE, MONEY_TREE_COL_TREE ); sqlx::query(&query).bind(tree_bytes).execute(&mut conn).await?; info!("Successfully initialized Merkle tree"); tree } }; Ok(merkle_tree) } async fn initialize_keypair(wallet: WalletPtr) -> Result { let mut conn = wallet.conn.acquire().await?; let query = format!( "SELECT {}, {} FROM {};", MONEY_KEYS_COL_PUBLIC, MONEY_KEYS_COL_SECRET, MONEY_KEYS_TABLE ); let keypair = match sqlx::query(&query).fetch_one(&mut conn).await { Ok(row) => { let public = deserialize(row.get(MONEY_KEYS_COL_PUBLIC))?; let secret = deserialize(row.get(MONEY_KEYS_COL_SECRET))?; Keypair { public, secret } } Err(_) => { let keypair = Keypair::random(&mut OsRng); let is_default = 0; let public_bytes = serialize(&keypair.public); let secret_bytes = serialize(&keypair.secret); let query = format!( "INSERT INTO {} ({}, {}, {}) VALUES (?1, ?2, ?3)", MONEY_KEYS_TABLE, MONEY_KEYS_COL_IS_DEFAULT, MONEY_KEYS_COL_PUBLIC, MONEY_KEYS_COL_SECRET ); sqlx::query(&query) .bind(is_default) .bind(public_bytes) .bind(secret_bytes) .execute(&mut conn) .await?; info!("Wrote keypair to wallet"); keypair } }; Ok(keypair) } // RPCAPI: // Processes a native token airdrop request and airdrops requested amount to address. // Returns the transaction ID upon success. // Params: // 0: base58 encoded address of the recipient // 1: Amount to airdrop in form of f64 // // --> {"jsonrpc": "2.0", "method": "airdrop", "params": ["1DarkFi...", 1.42], "id": 1} // <-- {"jsonrpc": "2.0", "result": "txID", "id": 1} async fn airdrop(&self, id: Value, params: &[Value]) -> JsonResult { if params.len() != 2 || !params[0].is_string() || !params[1].is_f64() { return JsonError::new(InvalidParams, None, id).into() } if !(*self.synced.lock().await) { error!("airdrop(): Blockchain is not yet synced"); return JsonError::new(InternalError, None, id).into() } let pubkey = match PublicKey::from_str(params[0].as_str().unwrap()) { Ok(v) => v, Err(e) => { error!("airdrop(): Failed parsing PublicKey from String: {}", e); return server_error(RpcError::ParseError, id) } }; let amount = params[1].as_f64().unwrap().to_string(); let amount = match decode_base10(&amount, 8, true) { Ok(v) => v, Err(_) => { error!("airdrop(): Failed parsing amount from string"); return server_error(RpcError::ParseError, id) } }; if amount > self.airdrop_limit { return server_error(RpcError::AmountExceedsLimit, id) } // Check if there as a previous airdrop and the timeout has passed. let now = Utc::now().timestamp(); let map = self.airdrop_map.lock().await; if let Some(last_airdrop) = map.get(&pubkey.to_bytes()) { if now - last_airdrop <= self.airdrop_timeout { return server_error(RpcError::TimeLimitReached, id) } }; drop(map); let cid = *MONEY_CONTRACT_ID; let (mint_zkbin, mint_pk, burn_zkbin, burn_pk) = { let proving_keys_r = self.proving_keys.read().await; let Some(arr) = proving_keys_r.get(&cid.to_bytes()) else { error!("Contract ID {} not found in proving keys hashmap", cid); return server_error(RpcError::InternalError, id) }; let Some(mint_data) = arr.iter().find(|x| x.0 == MONEY_CONTRACT_ZKAS_MINT_NS_V1) else { error!("{} proof data not found in vector", MONEY_CONTRACT_ZKAS_MINT_NS_V1); return server_error(RpcError::InternalError, id) }; let Some(burn_data) = arr.iter().find(|x| x.0 == MONEY_CONTRACT_ZKAS_BURN_NS_V1) else { error!("{} proof data not found in vector", MONEY_CONTRACT_ZKAS_BURN_NS_V1); return server_error(RpcError::InternalError, id) }; (mint_data.2.clone(), mint_data.1.clone(), burn_data.2.clone(), burn_data.1.clone()) }; // Create money contract transfer params and proofs let builder = TransferCallBuilder { keypair: self.keypair, recipient: pubkey, value: amount, token_id: *DARK_TOKEN_ID, rcpt_spend_hook: pallas::Base::zero(), rcpt_user_data: pallas::Base::zero(), rcpt_user_data_blind: pallas::Base::random(&mut OsRng), change_spend_hook: pallas::Base::zero(), change_user_data: pallas::Base::zero(), change_user_data_blind: pallas::Base::random(&mut OsRng), coins: vec![], tree: self.merkle_tree.clone(), mint_zkbin, mint_pk, burn_zkbin, burn_pk, clear_input: true, }; let debris = match builder.build() { Ok(v) => v, Err(e) => { error!("Failed to build transfer tx params: {}", e); return server_error(RpcError::InternalError, id) } }; // Build transaction let mut data = vec![MoneyTransfer as u8]; debris.params.encode(&mut data).unwrap(); let calls = vec![ContractCall { contract_id: cid, data }]; let proofs = vec![debris.proofs]; let mut tx = Transaction { calls, proofs, signatures: vec![] }; let sigs = tx.create_sigs(&mut OsRng, &debris.signature_secrets).unwrap(); tx.signatures = vec![sigs]; // Safety check to see if the transaction is actually valid. if let Err(e) = self.validator_state.read().await.verify_transactions(&[tx.clone()], false).await { error!("airdrop(): Failed to verify transaction before broadcasting: {}", e); return JsonError::new(InternalError, None, id).into() } // Broadcast transaction to the network. if let Err(e) = self.sync_p2p.broadcast(tx.clone()).await { error!("airdrop(): Failed broadcasting transaction: {}", e); return JsonError::new(InternalError, None, id).into() }; // Add/Update this airdrop into the hashmap let mut map = self.airdrop_map.lock().await; map.insert(pubkey.to_bytes(), now); drop(map); let tx_hash = blake3::hash(&serialize(&tx)).to_hex().as_str().to_string(); JsonResponse::new(json!(tx_hash), id).into() } } async fn prune_airdrop_map(map: Arc>>, timeout: i64) { loop { sleep(timeout as u64).await; debug!("Pruning airdrop map"); let now = Utc::now().timestamp(); let mut prune = vec![]; let im_map = map.lock().await; for (k, v) in im_map.iter() { if now - *v > timeout { prune.push(*k); } } drop(im_map); let mut mut_map = map.lock().await; for i in prune { mut_map.remove(&i); } drop(mut_map); } } async fn handle_signals( mut signals: Signals, _cfg_path: PathBuf, term_tx: smol::channel::Sender<()>, ) { debug!("Started signal handler"); while let Some(signal) = signals.next().await { match signal { SIGHUP => { info!("Caught SIGHUP"); } SIGTERM | SIGINT | SIGQUIT => { term_tx.send(()).await.unwrap(); } _ => unreachable!(), } } } async_daemonize!(realmain); async fn realmain(args: Args, ex: Arc>) -> Result<()> { let cfg_path = get_config_path(args.config, CONFIG_FILE)?; // Signal handling for config reload and graceful termination. let signals = Signals::new([SIGHUP, SIGTERM, SIGINT, SIGQUIT])?; let handle = signals.handle(); let (term_tx, term_rx) = smol::channel::bounded::<()>(1); let signals_task = task::spawn(handle_signals(signals, cfg_path.clone(), term_tx)); // Initialize or load wallet let wallet = init_wallet(&args.wallet_path, &args.wallet_pass).await?; // Initialize or open sled database let db_path = Path::new(expand_path(&args.database)?.to_str().unwrap()).join(args.chain.clone()); let sled_db = sled::open(&db_path)?; // Initialize validator state let (bootstrap_ts, genesis_ts, genesis_data, initial_distribution) = match args.chain.as_str() { "mainnet" => ( *MAINNET_BOOTSTRAP_TIMESTAMP, *MAINNET_GENESIS_TIMESTAMP, *MAINNET_GENESIS_HASH_BYTES, *MAINNET_INITIAL_DISTRIBUTION, ), "testnet" => ( *TESTNET_BOOTSTRAP_TIMESTAMP, *TESTNET_GENESIS_TIMESTAMP, *TESTNET_GENESIS_HASH_BYTES, *TESTNET_INITIAL_DISTRIBUTION, ), x => { error!("Unsupported chain `{}`", x); return Err(Error::UnsupportedChain) } }; // Parse faucet addresses let mut faucet_pubkeys = vec![]; for i in args.cashier_pub { let pk = PublicKey::from_str(&i)?; faucet_pubkeys.push(pk); } for i in args.faucet_pub { let pk = PublicKey::from_str(&i)?; faucet_pubkeys.push(pk); } // Initialize validator state let state = ValidatorState::new( &sled_db, bootstrap_ts, genesis_ts, genesis_data, initial_distribution, wallet.clone(), faucet_pubkeys, false, false, ) .await?; // P2P network. The faucet doesn't participate in consensus, so we only // build the sync protocol. let network_settings = net::Settings { inbound: args.sync_p2p_accept, outbound_connections: args.sync_slots, external_addr: args.sync_p2p_external, peers: args.sync_p2p_peer.clone(), seeds: args.sync_p2p_seed.clone(), outbound_transports: net::settings::get_outbound_transports(args.sync_p2p_transports), localnet: args.localnet, channel_log: args.channel_log, ..Default::default() }; let sync_p2p = net::P2p::new(network_settings).await; let registry = sync_p2p.protocol_registry(); info!("Registering block sync P2P protocols..."); let _state = state.clone(); registry .register(net::SESSION_ALL, move |channel, p2p| { let state = _state.clone(); async move { ProtocolSync::init(channel, state, p2p, false).await.unwrap() } }) .await; let _state = state.clone(); registry .register(net::SESSION_ALL, move |channel, p2p| { let state = _state.clone(); async move { ProtocolTx::init(channel, state, p2p).await.unwrap() } }) .await; let airdrop_timeout = args.airdrop_timeout; let airdrop_limit = decode_base10(&args.airdrop_limit, 8, true)?; // Initialize program state let faucetd = Faucetd::new( state.clone(), sync_p2p.clone(), wallet.clone(), airdrop_timeout, airdrop_limit, ) .await?; let faucetd = Arc::new(faucetd); // Task to periodically clean up the hashmap of airdrops. ex.spawn(prune_airdrop_map(faucetd.airdrop_map.clone(), airdrop_timeout)).detach(); // JSON-RPC server info!("Starting JSON-RPC server"); let _ex = ex.clone(); ex.spawn(listen_and_serve(args.rpc_listen, faucetd.clone(), _ex)).detach(); info!("Starting sync P2P network"); sync_p2p.clone().start(ex.clone()).await?; let _ex = ex.clone(); let _sync_p2p = sync_p2p.clone(); ex.spawn(async move { if let Err(e) = _sync_p2p.run(_ex).await { error!("Failed starting sync P2P network: {}", e); } }) .detach(); info!("Waiting for sync P2P outbound connections"); sync_p2p.clone().wait_for_outbound(ex).await?; match block_sync_task(sync_p2p, state.clone()).await { Ok(()) => *faucetd.synced.lock().await = true, Err(e) => error!("Failed syncing blockchain: {}", e), } // Wait for termination signal term_rx.recv().await?; print!("\r"); info!("Caught termination signal, cleaning up and exiting..."); handle.close(); signals_task.await; info!("Flushing database..."); let flushed_bytes = sled_db.flush_async().await?; info!("Flushed {} bytes", flushed_bytes); info!("Closing wallet connection..."); wallet.conn.close().await; info!("Closed wallet connection"); Ok(()) }