From 75a9e0f3de1b6e409762e299b7f316270f7d3ad0 Mon Sep 17 00:00:00 2001
From: Paul Hauner <paul@paulhauner.com>
Date: Mon, 11 Feb 2019 17:24:32 +1100
Subject: [PATCH] Add `verify_signature()` to `Attestation`

---
 eth2/types/src/attestation.rs | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/eth2/types/src/attestation.rs b/eth2/types/src/attestation.rs
index 7938ae6574..afffc2e2fd 100644
--- a/eth2/types/src/attestation.rs
+++ b/eth2/types/src/attestation.rs
@@ -1,6 +1,6 @@
-use super::{AttestationData, Bitfield, Hash256};
+use super::{AggregatePublicKey, AggregateSignature, AttestationData, Bitfield, Hash256};
 use crate::test_utils::TestRandom;
-use bls::AggregateSignature;
+use bls::bls_verify_aggregate;
 use rand::RngCore;
 use serde_derive::Serialize;
 use ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
@@ -21,6 +21,17 @@ impl Attestation {
     pub fn signable_message(&self, custody_bit: bool) -> Vec<u8> {
         self.data.signable_message(custody_bit)
     }
+
+    pub fn verify_signature(
+        &self,
+        group_public_key: &AggregatePublicKey,
+        custody_bit: bool,
+        // TODO: use domain.
+        _domain: u64,
+    ) -> bool {
+        self.aggregate_signature
+            .verify(&self.signable_message(custody_bit), group_public_key)
+    }
 }
 
 impl Encodable for Attestation {