Rename beacon_chain/ -> eth2/

eth2/utils/bls/src/lib.rs

@@ -0,0 +1,42 @@
+extern crate bls_aggregates;
+extern crate hashing;
+extern crate ssz;
+
+mod aggregate_signature;
+mod keypair;
+mod public_key;
+mod secret_key;
+mod signature;
+
+pub use crate::aggregate_signature::AggregateSignature;
+pub use crate::keypair::Keypair;
+pub use crate::public_key::PublicKey;
+pub use crate::secret_key::SecretKey;
+pub use crate::signature::Signature;
+
+pub use self::bls_aggregates::AggregatePublicKey;
+
+pub const BLS_AGG_SIG_BYTE_SIZE: usize = 97;
+
+use hashing::canonical_hash;
+use ssz::ssz_encode;
+use std::default::Default;
+
+fn extend_if_needed(hash: &mut Vec<u8>) {
+    // NOTE: bls_aggregates crate demands 48 bytes, this may be removed as we get closer to production
+    hash.resize(48, Default::default())
+}
+
+/// For some signature and public key, ensure that the signature message was the public key and it
+/// was signed by the secret key that corresponds to that public key.
+pub fn verify_proof_of_possession(sig: &Signature, pubkey: &PublicKey) -> bool {
+    let mut hash = canonical_hash(&ssz_encode(pubkey));
+    extend_if_needed(&mut hash);
+    sig.verify_hashed(&hash, &pubkey)
+}
+
+pub fn create_proof_of_possession(keypair: &Keypair) -> Signature {
+    let mut hash = canonical_hash(&ssz_encode(&keypair.pk));
+    extend_if_needed(&mut hash);
+    Signature::new_hashed(&hash, &keypair.sk)
+}