Add symmetric encryption support to Waku Message

src/lib/waku_message/index.spec.ts

@@ -90,6 +90,49 @@ describe('Waku Message', function () {
       )
     );
   });
+
+  it('Waku message round trip binary encryption [symmetric, no signature]', async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        async (payload, key) => {
+          const msg = await WakuMessage.fromBytes(payload, {
+            symKey: key,
+          });
+
+          const wireBytes = msg.encode();
+          const actual = await WakuMessage.decode(wireBytes, [key]);
+
+          expect(actual?.payload).to.deep.equal(payload);
+        }
+      )
+    );
+  });
+
+  it('Waku message round trip binary encryption [symmetric, signature]', async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        async (payload, sigPrivKey, symKey) => {
+          const sigPubKey = getPublicKey(sigPrivKey);
+
+          const msg = await WakuMessage.fromBytes(payload, {
+            symKey: symKey,
+            sigPrivKey: sigPrivKey,
+          });
+
+          const wireBytes = msg.encode();
+          const actual = await WakuMessage.decode(wireBytes, [symKey]);
+
+          expect(actual?.payload).to.deep.equal(payload);
+          expect(actual?.signaturePublicKey).to.deep.equal(sigPubKey);
+        }
+      )
+    );
+  });
 });
 
 describe('Interop: Nim', function () {

src/lib/waku_message/index.ts

@@ -25,10 +25,18 @@ export interface Options {
   timestamp?: Date;
   /**
    * Public Key to use to encrypt the messages using ECIES (Asymmetric Encryption).
+   *
+   * @throws if both `encPublicKey` and `symKey` are passed
    */
   encPublicKey?: Uint8Array | string;
   /**
-   * Private key to use to sign the message, `encPublicKey` must be provided as only
+   * Key to use to encrypt the messages using AES (Symmetric Encryption).
+   *
+   * @throws if both `encPublicKey` and `symKey` are passed
+   */
+  symKey?: Uint8Array | string;
+  /**
+   * Private key to use to sign the message, either `encPublicKey` or `symKey` must be provided as only
    * encrypted messages are signed.
    */
   sigPrivKey?: Uint8Array;
@@ -61,12 +69,15 @@ export class WakuMessage {
    *
    * If `opts.sigPrivKey` is passed and version 1 is used, the payload is signed
    * before encryption.
+   *
+   * @throws if both `opts.encPublicKey` and `opt.symKey` are passed
    */
   static async fromBytes(
     payload: Uint8Array,
     opts?: Options
   ): Promise<WakuMessage> {
-    const { timestamp, contentTopic, encPublicKey, sigPrivKey } = Object.assign(
+    const { timestamp, contentTopic, encPublicKey, symKey, sigPrivKey } =
+      Object.assign(
         { timestamp: new Date(), contentTopic: DefaultContentTopic },
         opts ? opts : {}
       );
@@ -74,11 +85,21 @@ export class WakuMessage {
     let _payload = payload;
     let version = DefaultVersion;
     let sig;
+
+    if (encPublicKey && symKey) {
+      throw 'Pass either `encPublicKey` or `symKey`, not both.';
+    }
+
     if (encPublicKey) {
       const enc = version_1.clearEncode(_payload, sigPrivKey);
       _payload = await version_1.encryptAsymmetric(enc.payload, encPublicKey);
       sig = enc.sig;
       version = 1;
+    } else if (symKey) {
+      const enc = version_1.clearEncode(_payload, sigPrivKey);
+      _payload = await version_1.encryptSymmetric(enc.payload, symKey);
+      sig = enc.sig;
+      version = 1;
     }
 
     return new WakuMessage(
@@ -127,19 +148,23 @@ export class WakuMessage {
     if (protoBuf.version === 1 && protoBuf.payload) {
       if (decPrivateKeys === undefined) {
         dbg('Payload is encrypted but no private keys have been provided.');
-
         return;
       }
 
       // Returns a bunch of `undefined` and hopefully one decrypted result
       const allResults = await Promise.all(
         decPrivateKeys.map(async (privateKey) => {
+          try {
+            return await version_1.decryptSymmetric(payload, privateKey);
+          } catch (e) {
+            dbg('Failed to decrypt message using symmetric encryption', e);
             try {
               return await version_1.decryptAsymmetric(payload, privateKey);
             } catch (e) {
-            dbg('Failed to decrypt asymmetric message', e);
+              dbg('Failed to decrypt message using asymmetric encryption', e);
               return;
             }
+          }
         })
       );
 

src/tests/browser/waku_message.spec.ts

@@ -0,0 +1,125 @@
+import { expect } from 'chai';
+import fc from 'fast-check';
+
+fc.configureGlobal({
+  interruptAfterTimeLimit: 1500,
+  markInterruptAsFailure: true,
+  numRuns: 10, // Firefox is too slow for 100 (fc default) runs in 2s (mocha default)
+});
+
+import { WakuMessage } from '../../lib/waku_message';
+import { getPublicKey } from '../../lib/waku_message/version_1';
+
+describe('Waku Message', function () {
+  it('Waku message round trip binary serialization [clear]', async function () {
+    await fc.assert(
+      fc.asyncProperty(fc.string(), async (s) => {
+        const msg = await WakuMessage.fromUtf8String(s);
+        const binary = msg.encode();
+        const actual = await WakuMessage.decode(binary);
+
+        expect(actual).to.deep.equal(msg);
+      })
+    );
+  });
+
+  it('Payload to utf-8', async function () {
+    await fc.assert(
+      fc.asyncProperty(fc.string(), async (s) => {
+        const msg = await WakuMessage.fromUtf8String(s);
+        const utf8 = msg.payloadAsUtf8;
+
+        return utf8 === s;
+      })
+    );
+  });
+
+  it('Waku message round trip binary encryption [asymmetric, no signature]', async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        async (payload, privKey) => {
+          const publicKey = getPublicKey(privKey);
+
+          const msg = await WakuMessage.fromBytes(payload, {
+            encPublicKey: publicKey,
+          });
+
+          const wireBytes = msg.encode();
+          const actual = await WakuMessage.decode(wireBytes, [privKey]);
+
+          expect(actual?.payload).to.deep.equal(payload);
+        }
+      )
+    );
+  });
+
+  it('Waku message round trip binary encryption [asymmetric, signature]', async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        async (payload, sigPrivKey, encPrivKey) => {
+          const sigPubKey = getPublicKey(sigPrivKey);
+          const encPubKey = getPublicKey(encPrivKey);
+
+          const msg = await WakuMessage.fromBytes(payload, {
+            encPublicKey: encPubKey,
+            sigPrivKey: sigPrivKey,
+          });
+
+          const wireBytes = msg.encode();
+          const actual = await WakuMessage.decode(wireBytes, [encPrivKey]);
+
+          expect(actual?.payload).to.deep.equal(payload);
+          expect(actual?.signaturePublicKey).to.deep.equal(sigPubKey);
+        }
+      )
+    );
+  });
+
+  it('Waku message round trip binary encryption [symmetric, no signature]', async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        async (payload, key) => {
+          const msg = await WakuMessage.fromBytes(payload, {
+            symKey: key,
+          });
+
+          const wireBytes = msg.encode();
+          const actual = await WakuMessage.decode(wireBytes, [key]);
+
+          expect(actual?.payload).to.deep.equal(payload);
+        }
+      )
+    );
+  });
+
+  it('Waku message round trip binary encryption [symmetric, signature]', async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        fc.uint8Array({ minLength: 32, maxLength: 32 }),
+        async (payload, sigPrivKey, symKey) => {
+          const sigPubKey = getPublicKey(sigPrivKey);
+
+          const msg = await WakuMessage.fromBytes(payload, {
+            symKey: symKey,
+            sigPrivKey: sigPrivKey,
+          });
+
+          const wireBytes = msg.encode();
+          const actual = await WakuMessage.decode(wireBytes, [symKey]);
+
+          expect(actual?.payload).to.deep.equal(payload);
+          expect(actual?.signaturePublicKey).to.deep.equal(sigPubKey);
+        }
+      )
+    );
+  });
+});