Merge pull request #41 from waku-org/danisharora/seeded-membershipkey…

…-generation

README.md

@@ -4,6 +4,7 @@ Browser library providing the cryptographic functions for Waku RLN Relay
 https://rfc.vac.dev/spec/17/
 
 ### Install
+
 ```
 npm install @waku/rln
 
@@ -13,6 +14,7 @@ yarn add @waku/rln
 ```
 
 ### Running example app
+
 ```
 git clone https://github.com/waku-org/js-rln
 
@@ -26,56 +28,71 @@ npm start
 
 Browse http://localhost:8080 and open the dev tools console to see the proof being generated and its verification
 
-
 ### Usage
 
 #### Initializing the library
+
 ```js
 import * as rln from "@waku/rln";
 
 const rlnInstance = wait rln.create();
 ```
 
 #### Generating RLN membership keypair
+
 ```js
 let memKeys = rlnInstance.generateMembershipKey();
 ```
 
+#### Generating RLN membership keypair using a seed
+
+```js
+let memKeys = rlnInstance.generateSeededMembershipKey(seed);
+```
 
 #### Adding membership keys into merkle tree
+
 ```js
 rlnInstance.insertMember(memKeys.IDCommitment);
 ```
 
 #### Generating a proof
+
 ```js
 // prepare the message
-const uint8Msg = Uint8Array.from("Hello World".split("").map(x => x.charCodeAt()));
+const uint8Msg = Uint8Array.from(
+  "Hello World".split("").map((x) => x.charCodeAt())
+);
 
 // setting up the epoch (With 0s for the test)
 const epoch = new Uint8Array(32);
 
 // generating a proof
-const proof = await rlnInstance.generateProof(uint8Msg, index, epoch, memKeys.IDKey)
+const proof = await rlnInstance.generateProof(
+  uint8Msg,
+  index,
+  epoch,
+  memKeys.IDKey
+);
 ```
 
 #### Verifying a proof
+
 ```js
 try {
-    // verify the proof
-    const verificationResult = rlnInstance.verifyProof(proof);
-    console.log("Is proof verified?", verificationResult ? "yes" : "no");
+  // verify the proof
+  const verificationResult = rlnInstance.verifyProof(proof);
+  console.log("Is proof verified?", verificationResult ? "yes" : "no");
 } catch (err) {
-    console.log("Invalid proof")
+  console.log("Invalid proof");
 }
 ```
 
-
-
 ### Updating circuit, verification key and zkey
+
 The RLN specs defines the defaults. These values are fixed and should not
 change. Currently, these [resources](https://github.com/vacp2p/zerokit/tree/master/rln/resources/tree_height_20) are being used.
-If they change, this file needs to be updated in `resources.ts` which 
+If they change, this file needs to be updated in `resources.ts` which
 contains these values encoded in base64 in this format:
 
 ```
@@ -85,37 +102,41 @@ const zkey = "...";
 export {verification_key, circuit, zkey};
 ```
 
-A tool like GNU's `base64` could be used to encode this data. 
+A tool like GNU's `base64` could be used to encode this data.
 
 ### Updating zerokit
+
 1. Make sure you have nodejs installed and a C compiler
 2. Install wasm-pack
+
 ```
 curl https://rustwasm.github.io/wasm-pack/installer/init.sh -sSf | sh
 ```
+
 3. Compile RLN for wasm
+
 ```
 git clone https://github.com/vacp2p/zerokit
 cd zerokit/rln-wasm
 wasm-pack build --release
 ```
-4. Copy `pkg/rln*` into `src/zerokit`
 
+4. Copy `pkg/rln*` into `src/zerokit`
 
 ## Bugs, Questions & Features
 
 If you encounter any bug or would like to propose new features, feel free to [open an issue](https://github.com/waku-org/js-rln/issues/new/).
 
-For more general discussion, help and latest news,  join [Vac Discord](https://discord.gg/PQFdubGt6d) or [Telegram](https://t.me/vacp2p).
-
+For more general discussion, help and latest news, join [Vac Discord](https://discord.gg/PQFdubGt6d) or [Telegram](https://t.me/vacp2p).
 
 ## License
+
 Licensed and distributed under either of
 
-* MIT license: [LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT
+- MIT license: [LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT
 
 or
 
-* Apache License, Version 2.0, ([LICENSE-APACHEv2](LICENSE-APACHEv2) or http://www.apache.org/licenses/LICENSE-2.0)
+- Apache License, Version 2.0, ([LICENSE-APACHEv2](LICENSE-APACHEv2) or http://www.apache.org/licenses/LICENSE-2.0)
 
 at your option. These files may not be copied, modified, or distributed except according to those terms.

package.json

@@ -125,6 +125,6 @@
     ]
   },
   "dependencies": {
-    "@waku/zerokit-rln-wasm": "^0.0.4"
+    "@waku/zerokit-rln-wasm": "^0.0.5"
   }
 }

src/index.spec.ts

@@ -58,4 +58,72 @@ describe("js-rln", () => {
       console.log(err);
     }
   });
+  it("should verify a proof with a seeded membership key generation", async function () {
+    const rlnInstance = await rln.create();
+    const seed = "This is a test seed";
+    const memKeys = rlnInstance.generateSeededMembershipKey(seed);
+
+    //peer's index in the Merkle Tree
+    const index = 5;
+
+    // Create a Merkle tree with random members
+    for (let i = 0; i < 10; i++) {
+      if (i == index) {
+        // insert the current peer's pk
+        rlnInstance.insertMember(memKeys.IDCommitment);
+      } else {
+        // create a new key pair
+        rlnInstance.insertMember(
+          rlnInstance.generateMembershipKey().IDCommitment
+        );
+      }
+    }
+
+    // prepare the message
+    const uint8Msg = Uint8Array.from(
+      "Hello World".split("").map((x) => x.charCodeAt(0))
+    );
+
+    // setting up the epoch
+    const epoch = new Date();
+
+    // generating proof
+    const proof = await rlnInstance.generateRLNProof(
+      uint8Msg,
+      index,
+      epoch,
+      memKeys.IDKey
+    );
+
+    try {
+      // verify the proof
+      const verifResult = rlnInstance.verifyRLNProof(proof, uint8Msg);
+      expect(verifResult).to.be.true;
+    } catch (err) {
+      assert.fail(0, 1, "should not have failed proof verification");
+    }
+
+    try {
+      // Modifying the signal so it's invalid
+      uint8Msg[4] = 4;
+      // verify the proof
+      const verifResult = rlnInstance.verifyRLNProof(proof, uint8Msg);
+      expect(verifResult).to.be.false;
+    } catch (err) {
+      console.log(err);
+    }
+  });
+  it("should generate the same membership key if the same seed is provided", async function () {
+    const rlnInstance = await rln.create();
+    const seed = "This is a test seed";
+    const memKeys1 = rlnInstance.generateSeededMembershipKey(seed);
+    const memKeys2 = rlnInstance.generateSeededMembershipKey(seed);
+
+    memKeys1.IDCommitment.forEach((element, index) => {
+      expect(element).to.equal(memKeys2.IDCommitment[index]);
+    });
+    memKeys1.IDKey.forEach((element, index) => {
+      expect(element).to.equal(memKeys2.IDKey[index]);
+    });
+  });
 });

src/rln.ts

@@ -125,6 +125,15 @@ export class RLNInstance {
     return MembershipKey.fromBytes(memKeys);
   }
 
+  generateSeededMembershipKey(seed: string): MembershipKey {
+    const seedBytes = stringEncoder.encode(seed);
+    const memKeys = zerokitRLN.generateSeededMembershipKey(
+      this.zkRLN,
+      seedBytes
+    );
+    return MembershipKey.fromBytes(memKeys);
+  }
+
   insertMember(idCommitment: Uint8Array): void {
     zerokitRLN.insertMember(this.zkRLN, idCommitment);
   }