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: https://github.com/supranational/blst/issues/11
- [x] Ensure milagro *and* blst are tested via CI
- [x] What to do with unsafe code?
- [x] Test infinity point in signature sets

consensus/types/src/aggregate_and_proof.rs

@@ -73,8 +73,7 @@ impl<T: EthSpec> AggregateAndProof<T> {
             genesis_validators_root,
         );
         let message = self.aggregate.data.slot.signing_root(domain);
-        self.selection_proof
-            .verify(message.as_bytes(), validator_pubkey)
+        self.selection_proof.verify(validator_pubkey, message)
     }
 }
 

consensus/types/src/attestation.rs

@@ -1,6 +1,6 @@
 use super::{
     AggregateSignature, AttestationData, BitList, ChainSpec, Domain, EthSpec, Fork, SecretKey,
-    Signature, SignedRoot,
+    SignedRoot,
 };
 use crate::{test_utils::TestRandom, Hash256};
 use safe_arith::ArithError;
@@ -44,7 +44,7 @@ impl<T: EthSpec> Attestation<T> {
         debug_assert!(self.signers_disjoint_from(other));
 
         self.aggregation_bits = self.aggregation_bits.union(&other.aggregation_bits);
-        self.signature.add_aggregate(&other.signature);
+        self.signature.add_assign_aggregate(&other.signature);
     }
 
     /// Signs `self`, setting the `committee_position`'th bit of `aggregation_bits` to `true`.
@@ -77,8 +77,7 @@ impl<T: EthSpec> Attestation<T> {
             );
             let message = self.data.signing_root(domain);
 
-            self.signature
-                .add(&Signature::new(message.as_bytes(), secret_key));
+            self.signature.add_assign(&secret_key.sign(message));
 
             Ok(())
         }

consensus/types/src/beacon_block.rs

@@ -35,7 +35,7 @@ impl<T: EthSpec> BeaconBlock<T> {
             parent_root: Hash256::zero(),
             state_root: Hash256::zero(),
             body: BeaconBlockBody {
-                randao_reveal: Signature::empty_signature(),
+                randao_reveal: Signature::empty(),
                 eth1_data: Eth1Data {
                     deposit_root: Hash256::zero(),
                     block_hash: Hash256::zero(),
@@ -63,7 +63,7 @@ impl<T: EthSpec> BeaconBlock<T> {
 
         let signed_header = SignedBeaconBlockHeader {
             message: header,
-            signature: Signature::empty_signature(),
+            signature: Signature::empty(),
         };
         let indexed_attestation: IndexedAttestation<T> = IndexedAttestation {
             attesting_indices: VariableList::new(vec![
@@ -72,7 +72,7 @@ impl<T: EthSpec> BeaconBlock<T> {
             ])
             .unwrap(),
             data: AttestationData::default(),
-            signature: AggregateSignature::new(),
+            signature: AggregateSignature::empty(),
         };
 
         let deposit_data = DepositData {
@@ -95,7 +95,7 @@ impl<T: EthSpec> BeaconBlock<T> {
             aggregation_bits: BitList::with_capacity(T::MaxValidatorsPerCommittee::to_usize())
                 .unwrap(),
             data: AttestationData::default(),
-            signature: AggregateSignature::new(),
+            signature: AggregateSignature::empty(),
         };
 
         let deposit = Deposit {
@@ -110,7 +110,7 @@ impl<T: EthSpec> BeaconBlock<T> {
 
         let signed_voluntary_exit = SignedVoluntaryExit {
             message: voluntary_exit,
-            signature: Signature::empty_signature(),
+            signature: Signature::empty(),
         };
 
         let mut block: BeaconBlock<T> = BeaconBlock::empty(spec);
@@ -200,7 +200,7 @@ impl<T: EthSpec> BeaconBlock<T> {
             genesis_validators_root,
         );
         let message = self.signing_root(domain);
-        let signature = Signature::new(message.as_bytes(), secret_key);
+        let signature = secret_key.sign(message);
         SignedBeaconBlock {
             message: self,
             signature,

consensus/types/src/beacon_block_header.rs

@@ -54,7 +54,7 @@ impl BeaconBlockHeader {
         let epoch = self.slot.epoch(E::slots_per_epoch());
         let domain = spec.get_domain(epoch, Domain::BeaconProposer, fork, genesis_validators_root);
         let message = self.signing_root(domain);
-        let signature = Signature::new(message.as_bytes(), secret_key);
+        let signature = secret_key.sign(message);
         SignedBeaconBlockHeader {
             message: self,
             signature,

consensus/types/src/beacon_state.rs

@@ -10,7 +10,7 @@ use int_to_bytes::{int_to_bytes4, int_to_bytes8};
 use pubkey_cache::PubkeyCache;
 use safe_arith::{ArithError, SafeArith};
 use serde_derive::{Deserialize, Serialize};
-use ssz::ssz_encode;
+use ssz::{ssz_encode, Encode};
 use ssz_derive::{Decode, Encode};
 use ssz_types::{typenum::Unsigned, BitVector, FixedVector};
 use std::convert::TryInto;
@@ -501,7 +501,7 @@ impl<T: EthSpec> BeaconState<T> {
             1,
             (committee.committee.len() as u64).safe_div(spec.target_aggregators_per_committee)?,
         );
-        let signature_hash = hash(&slot_signature.as_bytes());
+        let signature_hash = hash(&slot_signature.as_ssz_bytes());
         let signature_hash_int = u64::from_le_bytes(
             signature_hash[0..8]
                 .try_into()

consensus/types/src/deposit_data.rs

@@ -38,7 +38,7 @@ impl DepositData {
         let domain = spec.get_deposit_domain();
         let msg = self.as_deposit_message().signing_root(domain);
 
-        SignatureBytes::from(Signature::new(msg.as_bytes(), secret_key))
+        SignatureBytes::from(secret_key.sign(msg))
     }
 }
 

consensus/types/src/lib.rs

@@ -96,8 +96,7 @@ pub type Address = H160;
 pub type ForkVersion = [u8; 4];
 
 pub use bls::{
-    AggregatePublicKey, AggregateSignature, Keypair, PublicKey, PublicKeyBytes, SecretKey,
-    Signature, SignatureBytes,
+    AggregateSignature, Keypair, PublicKey, PublicKeyBytes, SecretKey, Signature, SignatureBytes,
 };
 pub use ssz_types::{typenum, typenum::Unsigned, BitList, BitVector, FixedVector, VariableList};
 pub use utils::{Graffiti, GRAFFITI_BYTES_LEN};

consensus/types/src/selection_proof.rs

@@ -27,7 +27,7 @@ impl SelectionProof {
         );
         let message = slot.signing_root(domain);
 
-        Self(Signature::new(message.as_bytes(), secret_key))
+        Self(secret_key.sign(message))
     }
 
     /// Returns the "modulo" used for determining if a `SelectionProof` elects an aggregator.
@@ -74,7 +74,7 @@ impl SelectionProof {
         );
         let message = slot.signing_root(domain);
 
-        self.0.verify(message.as_bytes(), pubkey)
+        self.0.verify(pubkey, message)
     }
 }
 

consensus/types/src/signed_aggregate_and_proof.rs

@@ -57,7 +57,7 @@ impl<T: EthSpec> SignedAggregateAndProof<T> {
 
         SignedAggregateAndProof {
             message,
-            signature: Signature::new(signing_message.as_bytes(), &secret_key),
+            signature: secret_key.sign(signing_message),
         }
     }
 
@@ -77,7 +77,7 @@ impl<T: EthSpec> SignedAggregateAndProof<T> {
             genesis_validators_root,
         );
         let message = self.message.signing_root(domain);
-        self.signature.verify(message.as_bytes(), validator_pubkey)
+        self.signature.verify(validator_pubkey, message)
     }
 
     /// Verifies the signature of the `AggregateAndProof` as well the underlying selection_proof in

consensus/types/src/signed_beacon_block.rs

@@ -78,7 +78,7 @@ impl<E: EthSpec> SignedBeaconBlock<E> {
             self.message.signing_root(domain)
         };
 
-        self.signature.verify(message.as_bytes(), pubkey)
+        self.signature.verify(pubkey, message)
     }
 
     /// Convenience accessor for the block's slot.

consensus/types/src/test_utils/builders/testing_attestation_builder.rs

@@ -36,7 +36,7 @@ impl<T: EthSpec> TestingAttestationBuilder<T> {
         let attestation = Attestation {
             aggregation_bits,
             data: data_builder.build(),
-            signature: AggregateSignature::new(),
+            signature: AggregateSignature::empty(),
         };
 
         Self {

consensus/types/src/test_utils/builders/testing_attester_slashing_builder.rs

@@ -64,7 +64,7 @@ impl TestingAttesterSlashingBuilder {
                 validator_indices.to_vec().into()
             },
             data: data_1,
-            signature: AggregateSignature::new(),
+            signature: AggregateSignature::empty(),
         };
 
         let mut attestation_2 = IndexedAttestation {
@@ -76,7 +76,7 @@ impl TestingAttesterSlashingBuilder {
                 validator_indices.to_vec().into()
             },
             data: data_2,
-            signature: AggregateSignature::new(),
+            signature: AggregateSignature::empty(),
         };
 
         let add_signatures = |attestation: &mut IndexedAttestation<T>| {
@@ -90,7 +90,7 @@ impl TestingAttesterSlashingBuilder {
 
             for validator_index in validator_indices {
                 let signature = signer(*validator_index, message.as_bytes());
-                attestation.signature.add(&signature);
+                attestation.signature.add_assign(&signature);
             }
         };
 

consensus/types/src/test_utils/builders/testing_beacon_block_builder.rs

@@ -101,7 +101,7 @@ impl<T: EthSpec> TestingBeaconBlockBuilder<T> {
         let epoch = self.block.slot.epoch(T::slots_per_epoch());
         let domain = spec.get_domain(epoch, Domain::Randao, fork, genesis_validators_root);
         let message = epoch.signing_root(domain);
-        self.block.body.randao_reveal = Signature::new(message.as_bytes(), sk);
+        self.block.body.randao_reveal = sk.sign(message);
     }
 
     /// Has the randao reveal been set?
@@ -368,7 +368,7 @@ impl<T: EthSpec> TestingBeaconBlockBuilder<T> {
     pub fn build_without_signing(self) -> SignedBeaconBlock<T> {
         SignedBeaconBlock {
             message: self.block,
-            signature: Signature::empty_signature(),
+            signature: Signature::empty(),
         }
     }
 }
@@ -410,7 +410,7 @@ pub fn build_double_vote_attester_slashing<T: EthSpec>(
             .iter()
             .position(|&i| i == validator_index)
             .expect("Unable to find attester slashing key");
-        Signature::new(message, secret_keys[key_index])
+        secret_keys[key_index].sign(Hash256::from_slice(message))
     };
 
     TestingAttesterSlashingBuilder::double_vote(

consensus/types/src/test_utils/builders/testing_deposit_builder.rs

@@ -41,7 +41,7 @@ impl TestingDepositBuilder {
                 // Creating invalid public key bytes
                 let mut public_key_bytes: Vec<u8> = vec![0; 48];
                 public_key_bytes[0] = 255;
-                pubkeybytes = PublicKeyBytes::from_bytes(&public_key_bytes).unwrap();
+                pubkeybytes = PublicKeyBytes::deserialize(&public_key_bytes).unwrap();
             }
             DepositTestTask::BadSig => secret_key = new_key.sk,
             _ => (),

consensus/types/src/test_utils/builders/testing_proposer_slashing_builder.rs

@@ -37,7 +37,7 @@ impl TestingProposerSlashingBuilder {
                 state_root: hash_1,
                 body_root: hash_1,
             },
-            signature: Signature::empty_signature(),
+            signature: Signature::empty(),
         };
 
         let slot_2 = if test_task == ProposerSlashingTestTask::ProposalEpochMismatch {
@@ -52,7 +52,7 @@ impl TestingProposerSlashingBuilder {
                 slot: slot_2,
                 ..signed_header_1.message
             },
-            signature: Signature::empty_signature(),
+            signature: Signature::empty(),
         };
 
         if test_task != ProposerSlashingTestTask::BadProposal1Signature {

consensus/types/src/test_utils/generate_deterministic_keypairs.rs

@@ -27,20 +27,10 @@ pub fn generate_deterministic_keypairs(validator_count: usize) -> Vec<Keypair> {
 ///
 /// This is used for testing only, and not to be used in production!
 pub fn generate_deterministic_keypair(validator_index: usize) -> Keypair {
-    let raw = keypair(validator_index);
-    Keypair {
-        pk: PublicKey::from_raw(raw.pk),
-        sk: SecretKey::from_raw(raw.sk),
-    }
+    keypair(validator_index)
 }
 
 /// Loads a list of keypairs from file.
 pub fn load_keypairs_from_yaml(path: PathBuf) -> Result<Vec<Keypair>, String> {
-    Ok(keypairs_from_yaml_file(path)?
-        .into_iter()
-        .map(|raw| Keypair {
-            pk: PublicKey::from_raw(raw.pk),
-            sk: SecretKey::from_raw(raw.sk),
-        })
-        .collect())
+    keypairs_from_yaml_file(path)
 }

consensus/types/src/test_utils/test_random/aggregate_signature.rs

@@ -4,8 +4,8 @@ use bls::{AggregateSignature, Signature};
 impl TestRandom for AggregateSignature {
     fn random_for_test(rng: &mut impl RngCore) -> Self {
         let signature = Signature::random_for_test(rng);
-        let mut aggregate_signature = AggregateSignature::new();
-        aggregate_signature.add(&signature);
+        let mut aggregate_signature = AggregateSignature::infinity();
+        aggregate_signature.add_assign(&signature);
         aggregate_signature
     }
 }

consensus/types/src/test_utils/test_random/public_key.rs

@@ -3,7 +3,6 @@ use bls::{PublicKey, SecretKey};
 
 impl TestRandom for PublicKey {
     fn random_for_test(rng: &mut impl RngCore) -> Self {
-        let secret_key = SecretKey::random_for_test(rng);
-        PublicKey::from_secret_key(&secret_key)
+        SecretKey::random_for_test(rng).public_key()
     }
 }

consensus/types/src/test_utils/test_random/public_key_bytes.rs

@@ -1,6 +1,6 @@
 use std::convert::From;
 
-use bls::{PublicKeyBytes, BLS_PUBLIC_KEY_BYTE_SIZE};
+use bls::{PublicKeyBytes, PUBLIC_KEY_BYTES_LEN};
 
 use super::*;
 
@@ -12,7 +12,7 @@ impl TestRandom for PublicKeyBytes {
             PublicKeyBytes::from(PublicKey::random_for_test(rng))
         } else {
             //invalid signature, just random bytes
-            PublicKeyBytes::from_bytes(&<[u8; BLS_PUBLIC_KEY_BYTE_SIZE]>::random_for_test(rng))
+            PublicKeyBytes::deserialize(&<[u8; PUBLIC_KEY_BYTES_LEN]>::random_for_test(rng))
                 .unwrap()
         }
     }

consensus/types/src/test_utils/test_random/signature.rs

@@ -7,6 +7,6 @@ impl TestRandom for Signature {
         let mut message = vec![0; 32];
         rng.fill_bytes(&mut message);
 
-        Signature::new(&message, &secret_key)
+        secret_key.sign(Hash256::from_slice(&message))
     }
 }

consensus/types/src/test_utils/test_random/signature_bytes.rs

@@ -1,4 +1,4 @@
-use bls::{SignatureBytes, BLS_SIG_BYTE_SIZE};
+use bls::{SignatureBytes, SIGNATURE_BYTES_LEN};
 
 use super::*;
 use std::convert::From;
@@ -11,7 +11,7 @@ impl TestRandom for SignatureBytes {
             SignatureBytes::from(Signature::random_for_test(rng))
         } else {
             //invalid signature, just random bytes
-            SignatureBytes::from_bytes(&<[u8; BLS_SIG_BYTE_SIZE]>::random_for_test(rng)).unwrap()
+            SignatureBytes::deserialize(&<[u8; SIGNATURE_BYTES_LEN]>::random_for_test(rng)).unwrap()
         }
     }
 }

consensus/types/src/tree_hash_impls.rs

@@ -71,7 +71,7 @@ fn process_pubkey_bytes_field(
     leaf: &mut Hash256,
     force_update: bool,
 ) -> bool {
-    let new_tree_hash = merkle_root(val.as_slice(), 0);
+    let new_tree_hash = merkle_root(val.as_serialized(), 0);
     process_slice_field(new_tree_hash.as_bytes(), leaf, force_update)
 }
 

consensus/types/src/voluntary_exit.rs

@@ -1,6 +1,6 @@
 use crate::{
-    test_utils::TestRandom, ChainSpec, Domain, Epoch, Fork, Hash256, SecretKey, Signature,
-    SignedRoot, SignedVoluntaryExit,
+    test_utils::TestRandom, ChainSpec, Domain, Epoch, Fork, Hash256, SecretKey, SignedRoot,
+    SignedVoluntaryExit,
 };
 
 use serde_derive::{Deserialize, Serialize};
@@ -36,10 +36,9 @@ impl VoluntaryExit {
             genesis_validators_root,
         );
         let message = self.signing_root(domain);
-        let signature = Signature::new(message.as_bytes(), &secret_key);
         SignedVoluntaryExit {
             message: self,
-            signature,
+            signature: secret_key.sign(message),
         }
     }
 }