_ Git - rapid-gossip-sync-server/blob - src/verifier.rs

   1 use std::convert::TryInto;
   2 use std::sync::Arc;
   3
   4 use bitcoin::{BlockHash, TxOut};
   5 use bitcoin::blockdata::block::Block;
   6 use bitcoin::hashes::Hash;
   7 use lightning::chain;
   8 use lightning::chain::AccessError;
   9 use lightning_block_sync::BlockSource;
  10 use lightning_block_sync::http::BinaryResponse;
  11 use lightning_block_sync::rest::RestClient;
  12
  13 use crate::config;
  14
  15 pub(crate) struct ChainVerifier {
  16         rest_client: Arc<RestClient>,
  17 }
  18
  19 struct RestBinaryResponse(Vec<u8>);
  20
  21 impl ChainVerifier {
  22         pub(crate) fn new() -> Self {
  23                 let rest_client = RestClient::new(config::bitcoin_rest_endpoint()).unwrap();
  24                 ChainVerifier {
  25                         rest_client: Arc::new(rest_client),
  26                 }
  27         }
  28
  29         fn retrieve_block(&self, block_height: u32) -> Result<Block, AccessError> {
  30                 let rest_client = self.rest_client.clone();
  31                 tokio::task::block_in_place(move || { tokio::runtime::Handle::current().block_on(async move {
  32                         let block_hash_result = rest_client.request_resource::<BinaryResponse, RestBinaryResponse>(&format!("blockhashbyheight/{}.bin", block_height)).await;
  33                         let block_hash: Vec<u8> = block_hash_result.map_err(|error| {
  34                                 eprintln!("Could't find block hash at height {}: {}", block_height, error.to_string());
  35                                 AccessError::UnknownChain
  36                         })?.0;
  37                         let block_hash = BlockHash::from_slice(&block_hash).unwrap();
  38
  39                         let block_result = rest_client.get_block(&block_hash).await;
  40                         let block = block_result.map_err(|error| {
  41                                 eprintln!("Couldn't retrieve block {}: {:?} ({})", block_height, error, block_hash);
  42                                 AccessError::UnknownChain
  43                         })?;
  44                         Ok(block)
  45                 }) })
  46         }
  47 }
  48
  49 impl chain::Access for ChainVerifier {
  50         fn get_utxo(&self, _genesis_hash: &BlockHash, short_channel_id: u64) -> Result<TxOut, AccessError> {
  51                 let block_height = (short_channel_id >> 5 * 8) as u32; // block height is most significant three bytes
  52                 let transaction_index = ((short_channel_id >> 2 * 8) & 0xffffff) as u32;
  53                 let output_index = (short_channel_id & 0xffff) as u16;
  54
  55                 let block = self.retrieve_block(block_height)?;
  56                 let transaction = block.txdata.get(transaction_index as usize).ok_or_else(|| {
  57                         eprintln!("Transaction index {} out of bounds in block {} ({})", transaction_index, block_height, block.block_hash().to_string());
  58                         AccessError::UnknownTx
  59                 })?;
  60                 let output = transaction.output.get(output_index as usize).ok_or_else(|| {
  61                         eprintln!("Output index {} out of bounds in transaction {}", output_index, transaction.txid().to_string());
  62                         AccessError::UnknownTx
  63                 })?;
  64                 Ok(output.clone())
  65         }
  66 }
  67
  68 impl TryInto<RestBinaryResponse> for BinaryResponse {
  69         type Error = std::io::Error;
  70
  71         fn try_into(self) -> Result<RestBinaryResponse, Self::Error> {
  72                 Ok(RestBinaryResponse(self.0))
  73         }
  74 }