rm unwraps inside methods, return params to private

.gitignore

@@ -1,2 +1,3 @@
 /target
-*.py
+*.py
+Cargo.lock

src/constraints.rs

@@ -5,14 +5,11 @@ use ark_crypto_primitives::sponge::{
 };
 use ark_ec::CurveGroup;
 use ark_ff::Field;
-use ark_relations::r1cs::ConstraintSystemRef;
-
 use ark_r1cs_std::{
     boolean::Boolean, fields::fp::FpVar, fields::nonnative::NonNativeFieldVar, groups::CurveVar,
     ToBitsGadget, ToConstraintFieldGadget,
 };
-
-use crate::Error;
+use ark_relations::r1cs::ConstraintSystemRef;
 
 /// CF stands for ConstraintField
 pub type CF<C> = <<C as CurveGroup>::BaseField as Field>::BasePrimeField;
@@ -24,29 +21,31 @@ pub fn verify(
     pk: GC,
     sig: (GC, NonNativeFieldVar<C::ScalarField, CF<C>>),
     msg: FpVar<CF<C>>,
-) -> Result<Boolean<CF<C>>, Error>
+) -> ark_relations::r1cs::Result<Boolean<CF<C>>>
 where
     C: CurveGroup,
     GC: CurveVar<C, CF<C>> + ToConstraintFieldGadget<CF<C>>,
 {
     let (r, s): (GC, NonNativeFieldVar<C::ScalarField, CF<C>>) = sig;
 
-    let r_xy = r.to_constraint_field().unwrap();
-    let pk_xy = pk.to_constraint_field().unwrap();
+    let r_xy = r.to_constraint_field()?;
+    let pk_xy = pk.to_constraint_field()?;
 
     let mut poseidon = PoseidonSpongeVar::new(cs.clone(), &poseidon_config);
-    poseidon.absorb(&r_xy).unwrap();
-    poseidon.absorb(&pk_xy).unwrap();
-    poseidon.absorb(&msg).unwrap();
-    let k = poseidon.squeeze_field_elements(1).unwrap();
-    let k = k.first().unwrap();
+    poseidon.absorb(&r_xy)?;
+    poseidon.absorb(&pk_xy)?;
+    poseidon.absorb(&msg)?;
+    let k = poseidon.squeeze_field_elements(1)?;
+    let k = k
+        .first()
+        .ok_or(ark_relations::r1cs::SynthesisError::Unsatisfiable)?;
 
-    let kx_b = pk.scalar_mul_le(k.to_bits_le().unwrap().iter()).unwrap();
+    let kx_b = pk.scalar_mul_le(k.to_bits_le()?.iter())?;
 
-    let g = GC::new_constant(cs.clone(), C::generator()).unwrap();
-    let s_b = g.scalar_mul_le(s.to_bits_le().unwrap().iter()).unwrap();
+    let g = GC::new_constant(cs.clone(), C::generator())?;
+    let s_b = g.scalar_mul_le(s.to_bits_le()?.iter())?;
     let r_rec: GC = s_b - kx_b;
-    Ok(r_rec.is_eq(&r).unwrap())
+    Ok(r_rec.is_eq(&r)?)
 }
 
 #[cfg(test)]
@@ -69,14 +68,16 @@ mod tests {
         let sk = SigningKey::<EdwardsConfig>::generate::<blake2::Blake2b512>(&mut OsRng).unwrap();
         let msg_raw = b"xxx yyy <<< zzz >>> bunny";
         let msg = Fq::from_le_bytes_mod_order(msg_raw);
-        let sig = sk.sign::<blake2::Blake2b512>(&poseidon_config, &msg);
+        let sig = sk
+            .sign::<blake2::Blake2b512>(&poseidon_config, &msg)
+            .unwrap();
         let pk = sk.public_key();
         pk.verify(&poseidon_config, &msg, &sig).unwrap();
 
         let cs = ConstraintSystem::<Fq>::new_ref();
-        let pk_var: GVar = GVar::new_witness(cs.clone(), || Ok(pk.0)).unwrap();
-        let r_var: GVar = GVar::new_witness(cs.clone(), || Ok(sig.r)).unwrap();
-        let s_var = NonNativeFieldVar::<Fr, Fq>::new_witness(cs.clone(), || Ok(sig.s)).unwrap();
+        let pk_var: GVar = GVar::new_witness(cs.clone(), || Ok(*pk.as_ref())).unwrap();
+        let r_var: GVar = GVar::new_witness(cs.clone(), || Ok(*sig.r())).unwrap();
+        let s_var = NonNativeFieldVar::<Fr, Fq>::new_witness(cs.clone(), || Ok(sig.s())).unwrap();
         let msg_var = FpVar::<Fq>::new_witness(cs.clone(), || Ok(msg)).unwrap();
 
         let res = verify::<G, GVar>(cs.clone(), poseidon_config, pk_var, (r_var, s_var), msg_var)

src/eddsa.rs

@@ -45,11 +45,11 @@ impl SecretKey {
 
 /// `PublicKey` is EdDSA signature verification key
 #[derive(Copy, Clone, Debug, CanonicalSerialize, CanonicalDeserialize)]
-pub struct PublicKey<TE: TECurveConfig>(pub Affine<TE>);
+pub struct PublicKey<TE: TECurveConfig>(Affine<TE>);
 
 impl<TE: TECurveConfig> PublicKey<TE> {
-    pub fn xy(&self) -> (&TE::BaseField, &TE::BaseField) {
-        self.as_ref().xy().unwrap()
+    pub fn xy(&self) -> Result<(&TE::BaseField, &TE::BaseField), Error> {
+        self.as_ref().xy().ok_or(Error::Coordinates)
     }
 
     pub fn to_bytes(&self) -> Vec<u8> {
@@ -125,7 +125,7 @@ where
         &self,
         poseidon: &PoseidonConfig<TE::BaseField>,
         message: &TE::BaseField,
-    ) -> Signature<TE> {
+    ) -> Result<Signature<TE>, Error> {
         let (x, prefix) = self.secret_key.expand::<TE::ScalarField, D>();
 
         let mut h = D::new();
@@ -140,22 +140,22 @@ where
 
         let mut poseidon = PoseidonSponge::new(poseidon);
 
-        let (sig_r_x, sig_r_y) = sig_r.xy().unwrap();
+        let (sig_r_x, sig_r_y) = sig_r.xy().ok_or(Error::Coordinates)?;
         poseidon.absorb(sig_r_x);
         poseidon.absorb(sig_r_y);
-        let (pk_x, pk_y) = self.public_key.0.xy().unwrap();
+        let (pk_x, pk_y) = self.public_key.0.xy().ok_or(Error::Coordinates)?;
         poseidon.absorb(pk_x);
         poseidon.absorb(pk_y);
         poseidon.absorb(message);
 
         // use poseidon over Fq, so that it can be done too in-circuit
         let k = poseidon.squeeze_field_elements::<TE::BaseField>(1);
-        let k = k.first().unwrap();
+        let k = k.first().ok_or(Error::BadDigestOutput)?;
         let k = TE::ScalarField::from_le_bytes_mod_order(&k.into_bigint().to_bytes_le());
 
         let sig_s = (x * k) + r;
 
-        Signature::new(sig_r, sig_s)
+        Ok(Signature::new(sig_r, sig_s))
     }
 }
 
@@ -181,17 +181,17 @@ where
     ) -> Result<(), Error> {
         let mut poseidon = PoseidonSponge::new(poseidon);
 
-        let (sig_r_x, sig_r_y) = signature.r().xy().unwrap();
+        let (sig_r_x, sig_r_y) = signature.r().xy().ok_or(Error::Coordinates)?;
         poseidon.absorb(sig_r_x);
         poseidon.absorb(sig_r_y);
-        let (pk_x, pk_y) = self.0.xy().unwrap();
+        let (pk_x, pk_y) = self.0.xy().ok_or(Error::Coordinates)?;
         poseidon.absorb(pk_x);
         poseidon.absorb(pk_y);
         poseidon.absorb(message);
 
         // use poseidon over Fq, so that it can be done too in-circuit
         let k = poseidon.squeeze_field_elements::<TE::BaseField>(1);
-        let k = k.first().unwrap();
+        let k = k.first().ok_or(Error::BadDigestOutput)?;
 
         let kx_b = self.0.mul_bigint(k.into_bigint());
         let s_b = Affine::<TE>::generator() * signature.s();

src/lib.rs

@@ -19,6 +19,7 @@ pub(crate) fn from_digest(digest: D) -> F {
 
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub enum Error {
+    Coordinates,
     Verify,
     BadDigestOutput,
 }
@@ -26,6 +27,7 @@ pub enum Error {
 impl core::fmt::Display for Error {
     fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
         match *self {
+            Error::Coordinates => write!(f, "Could not obtain the coordinates of a point"),
             Error::Verify => write!(f, "Signature verification failed"),
             Error::BadDigestOutput => write!(f, "Bad digest output size"),
         }
@@ -68,7 +70,7 @@ mod test {
         let signing_key = SigningKey::<TE>::generate::<D>(&mut OsRng).unwrap();
         let message_raw = b"xxx yyy <<< zzz >>> bunny";
         let message = TE::BaseField::from_le_bytes_mod_order(message_raw);
-        let signature = signing_key.sign::<D>(&poseidon, &message);
+        let signature = signing_key.sign::<D>(&poseidon, &message).unwrap();
         let public_key = signing_key.public_key();
         public_key.verify(&poseidon, &message, &signature).unwrap();
     }

src/signature.rs

@@ -6,8 +6,8 @@ use ark_serialize::CanonicalSerialize;
 /// `SignatureComponents` contains the realized parts of a signature
 #[derive(Copy, Clone, Debug, CanonicalSerialize, CanonicalDeserialize)]
 pub struct Signature<TE: TECurveConfig + Clone> {
-    pub r: Affine<TE>,
-    pub s: TE::ScalarField,
+    r: Affine<TE>,
+    s: TE::ScalarField,
 }
 
 impl<TE: TECurveConfig + Clone> Signature<TE> {