add masking

js/src/index.ts

@@ -39,14 +39,18 @@ export type CircuitInput = {
   body_hash_index?: string;
   partial_body_real_length?: string;
   partial_body_hash?: string[];
+  header_mask: string[];
+  body_mask: string[];
 };
 
 export type InputGenerationArgs = {
   ignoreBodyHashCheck?: boolean;
   shaPrecomputeSelector?: string;
-  maxHeadersLength?: number; // Max length of the email header including padding
-  maxBodyLength?: number; // Max length of the email body after shaPrecomputeSelector including padding
+  maxHeadersLength?: number;
+  maxBodyLength?: number;
   removeSoftLineBreaks?: boolean;
+  headerMask?: number[];
+  bodyMask?: number[];
 };
 
 // copied without modification, but not publicly exported in original
@@ -152,7 +156,7 @@ export function generateEmailVerifierInputsFromDKIMResult(
         maxRemainingBodyLength: maxBodyLength,
       }
     );
-    
+
     // code smell but it passes the linter
     let { bodyRemaining } = rest;
     // idk why this gets out of sync, todo: fix
@@ -179,11 +183,16 @@ export function generateEmailVerifierInputsFromDKIMResult(
       circuitInputs.body.len = remainingBodyLength.toString();
 
       // format back into u32 so noir doesn't have to do it
-      circuitInputs.partial_body_hash = Array.from(
-        u8ToU32(precomputedSha)
-      ).map((x) => x.toString());
+      circuitInputs.partial_body_hash = Array.from(u8ToU32(precomputedSha)).map(
+        (x) => x.toString()
+      );
     }
 
+    // masking
+    if (params.headerMask)
+      circuitInputs.header_mask = params.headerMask.map((x) => x.toString());
+    if (params.bodyMask)
+      circuitInputs.body_mask = params.bodyMask.map((x) => x.toString());
   }
 
   return circuitInputs;

js/tests/circuits.test.ts

@@ -5,7 +5,9 @@ import { generateEmailVerifierInputs } from "../src/index";
 import { makeEmailAddressCharTable } from "../src/utils";
 // import circuit1024 from "../../examples/verify_email_1024_bit_dkim/target/verify_email_1024_bit_dkim.json";
 import circuit2048 from "../../examples/verify_email_2048_bit_dkim/target/verify_email_2048_bit_dkim.json";
-import partialHash from "../../examples/partial_hash/target/partial_hash.json";
+import circuitPartialHash from "../../examples/partial_hash/target/partial_hash.json";
+import circuitEmailMask from "../../examples/email_mask/target/email_mask.json";
+
 const emails = {
   small: fs.readFileSync(path.join(__dirname, "./test-data/email-good.eml")),
   large: fs.readFileSync(
@@ -25,26 +27,30 @@ describe("ZKEmail.nr Circuit Unit Tests", () => {
   const selectorText = "All nodes in the Bitcoin network can consult it";
   let prover2048: ZKEmailProver;
   let proverPartialHash: ZKEmailProver;
+  let proverMasked: ZKEmailProver;
 
   beforeAll(() => {
     //@ts-ignore
     // prover1024 = new ZKEmailProver(circuit1024, "all");
     //@ts-ignore
     prover2048 = new ZKEmailProver(circuit2048, "all");
     //@ts-ignore
-    proverPartialHash = new ZKEmailProver(partialHash, "all");
+    proverPartialHash = new ZKEmailProver(circuitPartialHash, "all");
+    //@ts-ignore
+    proverMasked = new ZKEmailProver(circuitEmailMask, "all");
   });
 
   afterAll(async () => {
     // await prover1024.destroy();
     await prover2048.destroy();
     await proverPartialHash.destroy();
+    await proverMasked.destroy();
   });
 
   describe("Successful Cases", () => {
-    it("Char table: ", async () => {
-        console.log(makeEmailAddressCharTable());
-    })
+    // it("Char table: ", async () => {
+    //     console.log(makeEmailAddressCharTable());
+    // })
     xit("2048-bit DKIM", async () => {
       const inputs = await generateEmailVerifierInputs(
         emails.small,
@@ -59,6 +65,39 @@ describe("ZKEmail.nr Circuit Unit Tests", () => {
         maxBodyLength: 192,
       });
       await proverPartialHash.simulateWitness(inputs);
-    })
-  })
+    });
+    it("Masked Header/ Body", async () => {
+      // make masks
+      const headerMask = Array.from(
+        { length: inputParams.maxHeadersLength },
+        () => Math.floor(Math.random() * 2)
+      );
+      const bodyMask = Array.from({ length: inputParams.maxBodyLength }, () =>
+        Math.floor(Math.random() * 2)
+      );
+      const inputs = await generateEmailVerifierInputs(emails.small, {
+        headerMask,
+        bodyMask,
+        ...inputParams,
+      });
+      // simulate witness
+      const result = await proverMasked.simulateWitness(inputs);
+      // compute mask locally
+      const expectedMaskedHeader = inputs.header.storage.map((byte, i) =>
+        headerMask[i] === 1 ? parseInt(byte) : 0
+      );
+      const expectedMaskedBody = inputs.body!.storage.map((byte, i) =>
+        bodyMask[i] === 1 ? parseInt(byte) : 0
+      );
+      // compare results
+      const acutalMaskedHeader = result.returnValue[1].map((byte) =>
+        parseInt(byte, 16)
+      );
+      const acutalMaskedBody = result.returnValue[2].map((byte) =>
+        parseInt(byte, 16)
+      );
+      expect(expectedMaskedHeader).toEqual(acutalMaskedHeader);
+      expect(expectedMaskedBody).toEqual(acutalMaskedBody);
+    });
+  });
 });