[WIP] Feat plonk snark

crates/snark/Cargo.toml

@@ -26,7 +26,8 @@ log = { version = "0.4", features = ["std"] }
 pasta_curves = "0.5"
 
 # for load r1cs
-bellman_ce = { git = "https://github.com/matter-labs/bellman", version = "0.3.2" }
+bellman_ce = { version = "0.3.2", features = ["plonk"], git = "https://github.com/matter-labs/bellman.git", rev = "5520aa2" }
+rand = "0.4.6"
 bellpepper-core = "0.4.0"
 byteorder = "1.4.3"
 crypto-bigint = { version = "0.5.2", features = ["serde"] }

crates/snark/src/circuit/bellman.rs

@@ -1,6 +1,7 @@
 //! implement bellman proof system for circuit, this is useful for plonk and growth16
 
 use super::Circuit;
+use super::TrivialCircuit;
 use crate::prelude::bellman;
 use crate::prelude::bellman::pairing::Engine;
 use crate::prelude::bellman::ConstraintSystem;
@@ -54,3 +55,13 @@ where E::Fr: ff::PrimeField
         Ok(())
     }
 }
+
+
+impl<E: Engine> bellman::Circuit<E> for TrivialCircuit<E::Fr>
+where E::Fr: ff::PrimeField
+{
+    //noinspection RsBorrowChecker
+    fn synthesize<CS: ConstraintSystem<E>>(self, _cs: &mut CS) -> Result<(), SynthesisError> {
+	Ok(())
+    }
+}

crates/snark/src/circuit/bellpepper.rs

@@ -1,6 +1,7 @@
 //! implement bellpepper proof system for circuit
 
 use super::Circuit;
+use super::TrivialCircuit;
 use crate::prelude::bellpepper;
 use crate::prelude::bellpepper::num::AllocatedNum;
 use crate::prelude::bellpepper::ConstraintSystem;
@@ -53,3 +54,9 @@ impl<F: PrimeField> bellpepper::Circuit<F> for Circuit<F> {
         Ok(())
     }
 }
+
+impl<F: PrimeField> bellpepper::Circuit<F> for TrivialCircuit<F> {
+    fn synthesize<CS: ConstraintSystem<F>>(self, _cs: &mut CS) -> Result<(), SynthesisError> {
+	Ok(())
+    }
+}

crates/snark/src/circuit/mod.rs

@@ -25,7 +25,7 @@ pub mod bellpepper;
 
 /// Input of witness
 #[derive(Serialize, Deserialize, Clone)]
-pub struct Input<F: PrimeField> {
+pub struct Input<F: ff::PrimeField> {
     /// inner input
     pub input: Vec<(String, Vec<F>)>,
 }
@@ -291,3 +291,25 @@ impl<F: PrimeField> StepCircuit<F> for Circuit<F> {
         Ok(z_out)
     }
 }
+
+
+/// A trivial step circuit that simply returns the input
+/// from <https://github.com/microsoft/Nova/blob/master/src/traits/circuit.rs#L25>
+#[derive(Clone, Debug, Default, PartialEq, Eq)]
+pub struct TrivialCircuit<F: PrimeField> {
+  _p: core::marker::PhantomData<F>,
+}
+
+impl<F: PrimeField> StepCircuit<F> for TrivialCircuit<F> {
+  fn arity(&self) -> usize {
+    1
+  }
+
+  fn synthesize<CS: ConstraintSystem<F>>(
+    &self,
+    _cs: &mut CS,
+    z: &[AllocatedNum<F>],
+  ) -> core::result::Result<Vec<AllocatedNum<F>>, SynthesisError> {
+    Ok(z.to_vec())
+  }
+}