From d0f1a3e59f9c2040907275a5a6b5daa420c0c4bf Mon Sep 17 00:00:00 2001
From: Michael Sproul <michael@sigmaprime.io>
Date: Fri, 31 Jul 2020 05:47:11 +0000
Subject: [PATCH] Check deposit signatures when submitting via CLI (#1414)

## Proposed Changes

Having been bitten by submitting deposits with invalid signatures (for the wrong testnet), I'm proposing we check the signatures of deposits when submitting them via `lighthouse account validator deposit`.

The impact on performance is likely to be minimal because waiting for an Eth1 transaction confirmation takes a lot longer than verifying a single signature.

It would be great to have the same protection in the deposit web UI in the Lighthouse Book, but I imagine that will be obsoleted by the validator web UI work.
---
 account_manager/Cargo.toml               |  1 +
 account_manager/src/validator/deposit.rs | 10 ++++++++++
 2 files changed, 11 insertions(+)

diff --git a/account_manager/Cargo.toml b/account_manager/Cargo.toml
index 07dc309a5..dceee1368 100644
--- a/account_manager/Cargo.toml
+++ b/account_manager/Cargo.toml
@@ -11,6 +11,7 @@ slog = "2.5.2"
 slog-term = "2.5.0"
 slog-async = "2.5.0"
 types = { path = "../consensus/types" }
+state_processing = { path = "../consensus/state_processing" }
 dirs = "2.0.2"
 environment = { path = "../lighthouse/environment" }
 deposit_contract = { path = "../common/deposit_contract" }
diff --git a/account_manager/src/validator/deposit.rs b/account_manager/src/validator/deposit.rs
index 6ff002b0f..0e508cfd2 100644
--- a/account_manager/src/validator/deposit.rs
+++ b/account_manager/src/validator/deposit.rs
@@ -7,6 +7,7 @@ use futures::{
     stream::{FuturesUnordered, StreamExt},
 };
 use slog::{info, Logger};
+use state_processing::per_block_processing::verify_deposit_signature;
 use std::path::PathBuf;
 use tokio::time::{delay_until, Duration, Instant};
 use types::EthSpec;
@@ -135,6 +136,7 @@ where
     <T2 as web3::Transport>::Out: std::marker::Send,
 {
     let web3 = Web3::new(transport);
+    let spec = env.eth2_config.spec.clone();
 
     let deposits_fut = async {
         poll_until_synced(web3.clone(), log.clone()).await?;
@@ -143,6 +145,14 @@ where
             let futures = FuturesUnordered::default();
 
             for (ref mut validator_dir, eth1_deposit_data) in chunk.iter_mut() {
+                verify_deposit_signature(&eth1_deposit_data.deposit_data, &spec).map_err(|e| {
+                    format!(
+                        "Deposit for {:?} fails verification, \
+                         are you using the correct testnet configuration?\nError: {:?}",
+                        eth1_deposit_data.deposit_data.pubkey, e
+                    )
+                })?;
+
                 let web3 = web3.clone();
                 let log = log.clone();
                 futures.push(async move {