Support multiple BLS implementations (#1335)

## Issue Addressed

NA

## Proposed Changes

- Refactor the `bls` crate to support multiple BLS "backends" (e.g., milagro, blst, etc).
- Removes some duplicate, unused code in `common/rest_types/src/validator.rs`.
- Removes the old "upgrade legacy keypairs" functionality (these were unencrypted keys that haven't been supported for a few testnets, no one should be using them anymore).

## Additional Info

Most of the files changed are just inconsequential changes to function names.

## TODO

- [x] Optimization levels
- [x] Infinity point: supranational/blst#11
- [x] Ensure milagro *and* blst are tested via CI
- [x] What to do with unsafe code?
- [x] Test infinity point in signature sets

.github/workflows/test-suite.yml

@@ -77,7 +77,7 @@ jobs:
     - uses: actions/checkout@v1
     - name: Get latest version of stable Rust
       run: rustup update stable
-    - name: Run eth2.0-spec-tests with and without fake_crypto
+    - name: Run eth2.0-spec-tests with blst, milagro and fake_crypto
       run: make test-ef
   dockerfile-ubuntu:
     name: dockerfile-ubuntu

Makefile

@@ -35,6 +35,7 @@ check-benches:
 run-ef-tests:
 	cargo test --release --manifest-path=$(EF_TESTS)/Cargo.toml --features "ef_tests"
 	cargo test --release --manifest-path=$(EF_TESTS)/Cargo.toml --features "ef_tests,fake_crypto"
+	cargo test --release --manifest-path=$(EF_TESTS)/Cargo.toml --features "ef_tests,milagro"
 
 # Runs only the tests/state_transition_vectors tests.
 run-state-transition-tests:

account_manager/Cargo.toml

@@ -26,7 +26,7 @@ clap_utils = { path = "../common/clap_utils" }
 eth2_wallet = { path = "../crypto/eth2_wallet" }
 eth2_wallet_manager = { path = "../common/eth2_wallet_manager" }
 rand = "0.7.2"
-validator_dir = { path = "../common/validator_dir", features = ["unencrypted_keys"] }
+validator_dir = { path = "../common/validator_dir" }
 tokio = { version = "0.2.21", features = ["full"] }
 eth2_keystore = { path = "../crypto/eth2_keystore" }
 account_utils = { path = "../common/account_utils" }

account_manager/src/lib.rs

@@ -1,5 +1,4 @@
 mod common;
-pub mod upgrade_legacy_keypairs;
 pub mod validator;
 pub mod wallet;
 
@@ -19,15 +18,13 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
         .about("Utilities for generating and managing Ethereum 2.0 accounts.")
         .subcommand(wallet::cli_app())
         .subcommand(validator::cli_app())
-        .subcommand(upgrade_legacy_keypairs::cli_app())
 }
 
 /// Run the account manager, returning an error if the operation did not succeed.
 pub fn run<T: EthSpec>(matches: &ArgMatches<'_>, env: Environment<T>) -> Result<(), String> {
     match matches.subcommand() {
         (wallet::CMD, Some(matches)) => wallet::cli_run(matches)?,
         (validator::CMD, Some(matches)) => validator::cli_run(matches, env)?,
-        (upgrade_legacy_keypairs::CMD, Some(matches)) => upgrade_legacy_keypairs::cli_run(matches)?,
         (unknown, _) => {
             return Err(format!(
                 "{} is not a valid {} command. See --help.",

beacon_node/beacon_chain/Cargo.toml

@@ -9,6 +9,9 @@ default = ["participation_metrics"]
 write_ssz_files = []  # Writes debugging .ssz files to /tmp during block processing.
 participation_metrics = []  # Exposes validator participation metrics to Prometheus.
 
+[dev-dependencies]
+int_to_bytes = { path = "../../consensus/int_to_bytes" }
+
 [dependencies]
 eth2_config = { path = "../../common/eth2_config" }
 merkle_proof = { path = "../../consensus/merkle_proof" }

beacon_node/beacon_chain/src/attestation_verification.rs

@@ -521,7 +521,7 @@ pub fn verify_attestation_signature<T: BeaconChainTypes>(
     let _signature_verification_timer =
         metrics::start_timer(&metrics::ATTESTATION_PROCESSING_SIGNATURE_TIMES);
 
-    if signature_set.is_valid() {
+    if signature_set.verify() {
         Ok(())
     } else {
         Err(Error::InvalidSignature)
@@ -589,7 +589,7 @@ pub fn verify_signed_aggregate_signatures<T: BeaconChainTypes>(
         .map_err(BeaconChainError::SignatureSetError)?,
     ];
 
-    Ok(verify_signature_sets(signature_sets))
+    Ok(verify_signature_sets(signature_sets.iter()))
 }
 
 /// Assists in readability.

beacon_node/beacon_chain/src/beacon_chain.rs

@@ -862,7 +862,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                     root: target_root,
                 },
             },
-            signature: AggregateSignature::empty_signature(),
+            signature: AggregateSignature::empty(),
         })
     }
 
@@ -1654,7 +1654,7 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 },
             },
             // The block is not signed here, that is the task of a validator client.
-            signature: Signature::empty_signature(),
+            signature: Signature::empty(),
         };
 
         per_block_processing(

beacon_node/beacon_chain/src/builder.rs

@@ -666,7 +666,7 @@ fn genesis_block<T: EthSpec>(
         message: BeaconBlock::empty(&spec),
         // Empty signature, which should NEVER be read. This isn't to-spec, but makes the genesis
         // block consistent with every other block.
-        signature: Signature::empty_signature(),
+        signature: Signature::empty(),
     };
     genesis_block.message.state_root = genesis_state
         .update_tree_hash_cache()

beacon_node/beacon_chain/src/errors.rs

@@ -6,7 +6,6 @@ use crate::observed_attesters::Error as ObservedAttestersError;
 use crate::observed_block_producers::Error as ObservedBlockProducersError;
 use operation_pool::OpPoolError;
 use safe_arith::ArithError;
-use ssz::DecodeError;
 use ssz_types::Error as SszTypesError;
 use state_processing::{
     block_signature_verifier::Error as BlockSignatureVerifierError,
@@ -69,7 +68,7 @@ pub enum BeaconChainError {
     AttestationCacheLockTimeout,
     ValidatorPubkeyCacheLockTimeout,
     IncorrectStateForAttestation(RelativeEpochError),
-    InvalidValidatorPubkeyBytes(DecodeError),
+    InvalidValidatorPubkeyBytes(bls::Error),
     ValidatorPubkeyCacheIncomplete(usize),
     SignatureSetError(SignatureSetError),
     BlockSignatureVerifierError(state_processing::block_signature_verifier::Error),

beacon_node/beacon_chain/src/snapshot_cache.rs

@@ -99,7 +99,7 @@ mod test {
     use super::*;
     use types::{
         test_utils::{generate_deterministic_keypair, TestingBeaconStateBuilder},
-        BeaconBlock, Epoch, MainnetEthSpec, Signature, SignedBeaconBlock, Slot,
+        BeaconBlock, Epoch, MainnetEthSpec, SignedBeaconBlock, Slot,
     };
 
     const CACHE_SIZE: usize = 4;
@@ -115,7 +115,9 @@ mod test {
             beacon_state_root: Hash256::from_low_u64_be(i),
             beacon_block: SignedBeaconBlock {
                 message: BeaconBlock::empty(&spec),
-                signature: Signature::new(&[42], &generate_deterministic_keypair(0).sk),
+                signature: generate_deterministic_keypair(0)
+                    .sk
+                    .sign(Hash256::from_low_u64_be(42)),
             },
             beacon_block_root: Hash256::from_low_u64_be(i),
         }