chore: minor refactoring

packages/circuits/email-verifier.circom

@@ -9,8 +9,8 @@ include "./lib/sha.circom";
 include "./utils/array.circom";
 include "./utils/regex.circom";
 include "./utils/hash.circom";
+include "./utils/bytes.circom";
 include "./helpers/remove-soft-line-breaks.circom";
-include "./helpers/body-masker.circom";
 
 
 /// @title EmailVerifier
@@ -147,11 +147,11 @@ template EmailVerifier(maxHeadersLength, maxBodyLength, n, k, ignoreBodyHashChec
         if (enableBodyMasking == 1) {
             signal input mask[maxBodyLength];
             signal output maskedBody[maxBodyLength];
-            component bodyMasker = BodyMasker(maxBodyLength);
+            component byteMask = ByteMask(maxBodyLength);
 
-            bodyMasker.body <== emailBody;
-            bodyMasker.mask <== mask;
-            maskedBody <== bodyMasker.masked_body;
+            byteMask.body <== emailBody;
+            byteMask.mask <== mask;
+            maskedBody <== byteMask.maskedBody;
         }
     }
 

packages/circuits/tests/body-masker.test.ts

@@ -1,7 +1,7 @@
 import { wasm as wasm_tester } from "circom_tester";
 import path from "path";
 
-describe("BodyMasker Circuit", () => {
+describe("ByteMask Circuit", () => {
     let circuit: any;
 
     beforeAll(async () => {
@@ -24,7 +24,7 @@ describe("BodyMasker Circuit", () => {
         const witness = await circuit.calculateWitness(input);
         await circuit.checkConstraints(witness);
         await circuit.assertOut(witness, {
-            masked_body: [1, 0, 3, 0, 5, 0, 7, 0, 9, 0],
+            maskedBody: [1, 0, 3, 0, 5, 0, 7, 0, 9, 0],
         });
     });
 
@@ -38,7 +38,7 @@ describe("BodyMasker Circuit", () => {
             const witness = await circuit.calculateWitness(input);
             await circuit.checkConstraints(witness);
             await circuit.assertOut(witness, {
-                masked_body: [1, 0, 3, 0, 5, 0, 7, 0, 9, 0],
+                maskedBody: [1, 0, 3, 0, 5, 0, 7, 0, 9, 0],
             });
         } catch (error) {
             expect(error).toBeTruthy();

packages/circuits/tests/test-circuits/body-masker-test.circom

@@ -1,5 +1,5 @@
 pragma circom 2.1.6;
 
-include "../../helpers/body-masker.circom";
+include "../../utils/bytes.circom";
 
-component main = BodyMasker(10);
+component main = ByteMask(10);

packages/circuits/utils/bytes.circom

@@ -147,3 +147,39 @@ template SplitBytesToWords (l,n,k) {
     out[i] <== bits2num[i].out;
     }
 }
+
+// Asserts that a given input is binary.
+//
+// Inputs:
+// - in: an input signal, expected to be 0 or 1.
+template AssertBit() {
+    signal input in;
+    in * (in - 1) === 0;
+}
+
+// The ByteMask template masks an input body array using a binary mask array.
+// Each element in the body array is multiplied by the corresponding element in the mask array.
+// The mask array is validated to ensure all elements are binary (0 or 1).
+//
+// Parameters:
+// - maxBodyLength: The maximum length of the body and mask arrays.
+//
+// Inputs:
+// - body: An array of signals representing the body to be masked.
+// - mask: An array of signals representing the binary mask.
+//
+// Outputs:
+// - maskedBody: An array of signals representing the masked body.
+template ByteMask(maxBodyLength) {
+    signal input body[maxBodyLength];
+    signal input mask[maxBodyLength];
+    signal output maskedBody[maxBodyLength];
+
+    component bit_check[maxBodyLength];
+
+    for (var i = 0; i < maxBodyLength; i++) {
+        bit_check[i] = AssertBit();
+        bit_check[i].in <== mask[i];
+        maskedBody[i] <== body[i] * mask[i];
+    }
+}