use super::*;
impl<N: Network> FromBits for Signature<N> {
fn from_bits_le(bits_le: &[bool]) -> Result<Self> {
let scalar_size_in_bits = Scalar::<N>::size_in_bits();
let compute_key_size_in_bits = ComputeKey::<N>::size_in_bits();
let (challenge_start, challenge_end) = (0, scalar_size_in_bits);
let (response_start, response_end) = (challenge_end, challenge_end + scalar_size_in_bits);
let (compute_key_start, compute_key_end) = (response_end, response_end + compute_key_size_in_bits);
let Some(challenge_bits) = bits_le.get(challenge_start..challenge_end) else {
bail!("Unable to recover the signature challenge from (LE) bits");
};
let Some(response_bits) = bits_le.get(response_start..response_end) else {
bail!("Unable to recover the signature response from (LE) bits");
};
let Some(compute_key_bits) = bits_le.get(compute_key_start..compute_key_end) else {
bail!("Unable to recover the signature compute key from (LE) bits");
};
Ok(Self {
challenge: Scalar::from_bits_le(challenge_bits)?,
response: Scalar::from_bits_le(response_bits)?,
compute_key: ComputeKey::from_bits_le(compute_key_bits)?,
})
}
fn from_bits_be(bits_be: &[bool]) -> Result<Self> {
let scalar_size_in_bits = Scalar::<N>::size_in_bits();
let compute_key_size_in_bits = ComputeKey::<N>::size_in_bits();
let (challenge_start, challenge_end) = (0, scalar_size_in_bits);
let (response_start, response_end) = (challenge_end, challenge_end + scalar_size_in_bits);
let (compute_key_start, compute_key_end) = (response_end, response_end + compute_key_size_in_bits);
let Some(challenge_bits) = bits_be.get(challenge_start..challenge_end) else {
bail!("Unable to recover the signature challenge from (BE) bits");
};
let Some(response_bits) = bits_be.get(response_start..response_end) else {
bail!("Unable to recover the signature response from (BE) bits");
};
let Some(compute_key_bits) = bits_be.get(compute_key_start..compute_key_end) else {
bail!("Unable to recover the signature compute key from (BE) bits");
};
Ok(Self {
challenge: Scalar::from_bits_be(challenge_bits)?,
response: Scalar::from_bits_be(response_bits)?,
compute_key: ComputeKey::from_bits_be(compute_key_bits)?,
})
}
}
#[cfg(test)]
mod tests {
use super::*;
use snarkvm_console_network::Testnet3;
type CurrentNetwork = Testnet3;
const ITERATIONS: usize = 100;
fn check_from_bits_le() -> Result<()> {
let rng = &mut TestRng::default();
for i in 0..ITERATIONS {
let expected = test_helpers::sample_signature(i as u64, rng);
let given_bits = expected.to_bits_le();
assert_eq!(Signature::<CurrentNetwork>::size_in_bits(), given_bits.len());
let candidate = Signature::<CurrentNetwork>::from_bits_le(&given_bits)?;
assert_eq!(expected, candidate);
let candidate = vec![given_bits, vec![false; i]].concat();
let candidate = Signature::<CurrentNetwork>::from_bits_le(&candidate)?;
assert_eq!(expected, candidate);
assert_eq!(Signature::<CurrentNetwork>::size_in_bits(), candidate.to_bits_le().len());
}
Ok(())
}
fn check_from_bits_be() -> Result<()> {
let rng = &mut TestRng::default();
for i in 0..ITERATIONS {
let expected = test_helpers::sample_signature(i as u64, rng);
let given_bits = expected.to_bits_be();
assert_eq!(Signature::<CurrentNetwork>::size_in_bits(), given_bits.len());
let candidate = Signature::<CurrentNetwork>::from_bits_be(&given_bits)?;
assert_eq!(expected, candidate);
let candidate = vec![given_bits, vec![false; i]].concat();
let candidate = Signature::<CurrentNetwork>::from_bits_be(&candidate)?;
assert_eq!(expected, candidate);
assert_eq!(Signature::<CurrentNetwork>::size_in_bits(), candidate.to_bits_be().len());
}
Ok(())
}
#[test]
fn test_from_bits_le() -> Result<()> {
check_from_bits_le()
}
#[test]
fn test_from_bits_be() -> Result<()> {
check_from_bits_be()
}
}