lighthouse/eth2/utils/bls/src/fake_aggregate_signature.rs
Paul Hauner 7cbee46227
Add FakeSignature and FakeAggregateSignature
They replace Signature and FakeAggregateSignature when compling with
debug. Compiling with release uses the real structs.
2019-03-22 10:08:40 +11:00

118 lines
3.0 KiB
Rust

use super::{fake_signature::FakeSignature, AggregatePublicKey};
use serde::de::{Deserialize, Deserializer};
use serde::ser::{Serialize, Serializer};
use serde_hex::{encode as hex_encode, PrefixedHexVisitor};
use ssz::{
decode_ssz_list, hash, ssz_encode, Decodable, DecodeError, Encodable, SszStream, TreeHash,
};
const SIGNATURE_LENGTH: usize = 48;
/// A BLS aggregate signature.
///
/// This struct is a wrapper upon a base type and provides helper functions (e.g., SSZ
/// serialization).
#[derive(Debug, PartialEq, Clone, Default, Eq)]
pub struct FakeAggregateSignature {
bytes: Vec<u8>,
}
impl FakeAggregateSignature {
/// Creates a new all-zero's signature
pub fn new() -> Self {
Self::zero()
}
/// Creates a new all-zero's signature
pub fn zero() -> Self {
Self {
bytes: vec![0; SIGNATURE_LENGTH],
}
}
/// Does glorious nothing.
pub fn add(&mut self, _signature: &FakeSignature) {
// Do nothing.
}
/// _Always_ returns `true`.
pub fn verify(
&self,
_msg: &[u8],
_domain: u64,
_aggregate_public_key: &AggregatePublicKey,
) -> bool {
true
}
/// _Always_ returns `true`.
pub fn verify_multiple(
&self,
_messages: &[&[u8]],
_domain: u64,
_aggregate_public_keys: &[&AggregatePublicKey],
) -> bool {
true
}
}
impl Encodable for FakeAggregateSignature {
fn ssz_append(&self, s: &mut SszStream) {
s.append_vec(&self.bytes);
}
}
impl Decodable for FakeAggregateSignature {
fn ssz_decode(bytes: &[u8], i: usize) -> Result<(Self, usize), DecodeError> {
let (sig_bytes, i) = decode_ssz_list(bytes, i)?;
Ok((FakeAggregateSignature { bytes: sig_bytes }, i))
}
}
impl Serialize for FakeAggregateSignature {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
serializer.serialize_str(&hex_encode(ssz_encode(self)))
}
}
impl<'de> Deserialize<'de> for FakeAggregateSignature {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
let bytes = deserializer.deserialize_str(PrefixedHexVisitor)?;
let (obj, _) = <_>::ssz_decode(&bytes[..], 0)
.map_err(|e| serde::de::Error::custom(format!("invalid ssz ({:?})", e)))?;
Ok(obj)
}
}
impl TreeHash for FakeAggregateSignature {
fn hash_tree_root(&self) -> Vec<u8> {
hash(&self.bytes)
}
}
#[cfg(test)]
mod tests {
use super::super::{Keypair, Signature};
use super::*;
use ssz::ssz_encode;
#[test]
pub fn test_ssz_round_trip() {
let keypair = Keypair::random();
let mut original = FakeAggregateSignature::new();
original.add(&Signature::new(&[42, 42], 0, &keypair.sk));
let bytes = ssz_encode(&original);
let (decoded, _) = FakeAggregateSignature::ssz_decode(&bytes, 0).unwrap();
assert_eq!(original, decoded);
}
}