Configure Sinsemilla chip

src/circuit/gadget/sinsemilla/chip.rs

@@ -48,10 +48,13 @@ impl<F: FieldExt> MessagePiece<F> {
 /// TODO: Configuration for the Sinsemilla hash chip
 #[derive(Clone, Debug)]
 pub struct SinsemillaConfig {
+    q_sinsemilla1: Selector,
+    q_sinsemilla2: Selector,
     bits: Column<Advice>,
     x_a: Column<Advice>,
     x_p: Column<Advice>,
     lambda: (Column<Advice>, Column<Advice>),
+    perm: Permutation,
     generator_table: GeneratorTableConfig,
     ecc_config: EccConfig,
 }
@@ -118,6 +121,8 @@ impl<C: CurveAffine> SinsemillaChip<C> {
     ) -> <Self as Chip<C::Base>>::Config {
         // Sinsemilla selector for lookup and expr1
         let q_sinsemilla1 = meta.selector();
+        // Sinsemilla selector for expr2
+        let q_sinsemilla2 = meta.selector();
 
         // Rename advice columns for the Sinsemilla context
         let bits = advices[0];
@@ -129,7 +134,64 @@ impl<C: CurveAffine> SinsemillaChip<C> {
         let generator_table =
             GeneratorTableChip::<C>::configure(meta, q_sinsemilla1, lookup, bits, x_a, x_p, lambda);
 
-        todo!()
+        // Create custom gates
+        meta.create_gate("Sinsemilla gate 1", |meta| {
+            // (λ_{2,i})^2 − (x_{A,i+1} + (λ_{1,i}^2 − x_{A,i} − x_{P,i}) + x_{A,i})
+            let expr1 = {
+                let q_sinsemilla1 = meta.query_selector(q_sinsemilla1, Rotation::cur());
+                let lambda1 = meta.query_advice(lambda.0, Rotation::cur());
+                let lambda1_sq = lambda1.clone() * lambda1;
+                let lambda2 = meta.query_advice(lambda.1, Rotation::cur());
+                let lambda2_sq = lambda2.clone() * lambda2;
+                let x_a_next = meta.query_advice(x_a, Rotation::next());
+                let x_p_cur = meta.query_advice(x_p, Rotation::cur());
+
+                q_sinsemilla1 * (lambda2_sq - (x_a_next + (lambda1_sq - x_p_cur)))
+            };
+            vec![expr1]
+        });
+
+        meta.create_gate("Sinsemilla gate 2", |meta| {
+            // 2⋅λ_{2,i}⋅(x_{A,i} − x_{A,i+1}) − (y_{A,i} + y_{A,i+1})
+            // where y_{A,j} = [(λ_{1,j} + λ_{2,j})⋅(x_{A,j} − (λ_{1,j}^2 − x_{A,j} − x_{P,j}))] / 2
+            let expr2 = {
+                let q_sinsemilla2 = meta.query_selector(q_sinsemilla2, Rotation::cur());
+                let lambda1_cur = meta.query_advice(lambda.0, Rotation::cur());
+                let lambda1_cur_sq = lambda1_cur.clone() * lambda1_cur.clone();
+                let lambda1_next = meta.query_advice(lambda.0, Rotation::next());
+                let lambda1_next_sq = lambda1_next.clone() * lambda1_next.clone();
+                let lambda2_cur = meta.query_advice(lambda.1, Rotation::cur());
+                let lambda2_next = meta.query_advice(lambda.1, Rotation::next());
+                let x_a_cur = meta.query_advice(x_a, Rotation::cur());
+                let x_a_next = meta.query_advice(x_a, Rotation::next());
+                let x_p_cur = meta.query_advice(x_p, Rotation::cur());
+                let x_p_next = meta.query_advice(x_p, Rotation::next());
+
+                let y_a_cur = (lambda1_cur + lambda2_cur.clone())
+                    * (x_a_cur.clone() - (lambda1_cur_sq - x_a_cur.clone() - x_p_cur))
+                    * C::Base::TWO_INV;
+
+                let y_a_next = (lambda1_next + lambda2_next)
+                    * (x_a_next.clone() - (lambda1_next_sq - x_a_next.clone() - x_p_next))
+                    * C::Base::TWO_INV;
+
+                q_sinsemilla2 * (lambda2_cur * (x_a_cur - x_a_next) - (y_a_cur + y_a_next))
+            };
+
+            vec![expr2]
+        });
+
+        SinsemillaConfig {
+            q_sinsemilla1,
+            q_sinsemilla2,
+            bits,
+            x_a,
+            x_p,
+            lambda,
+            perm,
+            generator_table,
+            ecc_config,
+        }
     }
 }
 

src/circuit/gadget/sinsemilla/chip/generator_table.rs

@@ -62,26 +62,28 @@ impl<C: CurveAffine> GeneratorTableChip<C> {
             let table_idx_cur = meta.query_fixed(lookup.0, Rotation::cur());
             let table_x_cur = meta.query_fixed(lookup.1, Rotation::cur());
             let table_y_cur = meta.query_fixed(lookup.2, Rotation::cur());
-    
+
             // m_{i+1} = z_{i} - 2^K * z_{i + 1}
             let bits_cur = meta.query_advice(bits, Rotation::cur());
             let bits_next = meta.query_advice(bits, Rotation::next());
             let bits = bits_cur - (bits_next * C::Base::from_u64(1 << K));
-    
+
             let x_a_cur = meta.query_advice(x_a, Rotation::cur());
             let x_p_cur = meta.query_advice(x_p, Rotation::cur());
             let lambda1_cur = meta.query_advice(lambda.0, Rotation::cur());
             let lambda2_cur = meta.query_advice(lambda.1, Rotation::cur());
             let y_a_cur = (lambda1_cur.clone() + lambda2_cur)
                 * (x_a_cur.clone()
-                    - (lambda1_cur.clone() * lambda1_cur.clone() - x_a_cur.clone() - x_p_cur.clone()))
+                    - (lambda1_cur.clone() * lambda1_cur.clone()
+                        - x_a_cur.clone()
+                        - x_p_cur.clone()))
                 * C::Base::TWO_INV;
-    
+
             // y_p = y_a - lambda1 ⋅ (x_a - x_p)
             let y_p = y_a_cur - lambda1_cur * (x_a_cur - x_p_cur.clone());
-    
+
             let init_p = get_s_by_idx::<C>(0).to_affine().coordinates().unwrap();
-    
+
             // Lookup expressions default to the first entry when `q_sinsemilla`
             // is not enabled.
             let m = sinsemilla_cur.clone() * bits
@@ -90,12 +92,8 @@ impl<C: CurveAffine> GeneratorTableChip<C> {
                 + (Expression::Constant(C::Base::one()) - sinsemilla_cur.clone()) * *init_p.x();
             let y_p = sinsemilla_cur.clone() * y_p
                 + (Expression::Constant(C::Base::one()) - sinsemilla_cur) * *init_p.y();
-
-            vec![
-                (m, table_idx_cur),
-                (x_p, table_x_cur),
-                (y_p,table_y_cur)
-            ]
+
+            vec![(m, table_idx_cur), (x_p, table_x_cur), (y_p, table_y_cur)]
         });
 
         GeneratorTableConfig {