feat!: enable validation of meta field

waku-org · Mar 13, 2023 · 2dcd16f · 2dcd16f
1 parent 702d3dd
commit 2dcd16f
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Showing 9 changed files with 394 additions and 17 deletions.
diff --git a/packages/core/src/lib/message/topic_only_message.ts b/packages/core/src/lib/message/topic_only_message.ts
@@ -23,6 +23,10 @@ export class TopicOnlyMessage implements IDecodedMessage {
   get contentTopic(): string {
     return this.proto.contentTopic;
   }
+
+  isMetaValid(): boolean {
+    return true;
+  }
 }
 
 export class TopicOnlyDecoder implements IDecoder<TopicOnlyMessage> {

diff --git a/packages/core/src/lib/message/version_0.spec.ts b/packages/core/src/lib/message/version_0.spec.ts
@@ -105,4 +105,104 @@ describe("Waku Message version 0", function () {
       )
     );
   });
+
+  it("isMetaValid returns true when no validator specified", async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.string(),
+        fc.string(),
+        fc.uint8Array({ minLength: 1 }),
+        async (pubSubTopic, contentTopic, payload) => {
+          const encoder = createEncoder({
+            contentTopic,
+          });
+          const bytes = await encoder.toWire({ payload });
+          const decoder = createDecoder(contentTopic);
+          const protoResult = await decoder.fromWireToProtoObj(bytes);
+          const result = (await decoder.fromProtoObj(
+            pubSubTopic,
+            protoResult!
+          )) as DecodedMessage;
+
+          expect(result.isMetaValid()).to.be.true;
+        }
+      )
+    );
+  });
+
+  it("isMetaValid returns false when validator specified returns false", async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.string(),
+        fc.string(),
+        fc.uint8Array({ minLength: 1 }),
+        async (pubSubTopic, contentTopic, payload) => {
+          const encoder = createEncoder({
+            contentTopic,
+          });
+          const decoder = createDecoder(contentTopic, () => false);
+
+          const bytes = await encoder.toWire({ payload });
+          const protoResult = await decoder.fromWireToProtoObj(bytes);
+          const result = (await decoder.fromProtoObj(
+            pubSubTopic,
+            protoResult!
+          )) as DecodedMessage;
+
+          expect(result.isMetaValid()).to.be.false;
+        }
+      )
+    );
+  });
+
+  it("isMetaValid returns true when matching meta setter", async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.string(),
+        fc.string(),
+        fc.uint8Array({ minLength: 1 }),
+        async (pubSubTopic, contentTopic, payload) => {
+          const metaSetter = (
+            msg: IProtoMessage & { meta: undefined }
+          ): Uint8Array => {
+            const buffer = new ArrayBuffer(4);
+            const view = new DataView(buffer);
+            view.setUint32(0, msg.payload.length);
+            return new Uint8Array(buffer);
+          };
+
+          const encoder = createEncoder({
+            contentTopic,
+            metaSetter,
+          });
+
+          const metaValidator = (
+            _pubSubTopic: string,
+            message: IProtoMessage
+          ): boolean => {
+            if (!message.meta) return false;
+
+            const view = new DataView(
+              message.meta.buffer,
+              message.meta.byteOffset,
+              4
+            );
+            const metaInt = view.getUint32(0);
+
+            return metaInt === message.payload.length;
+          };
+          const decoder = createDecoder(contentTopic, metaValidator);
+
+          const bytes = await encoder.toWire({ payload });
+          const protoResult = await decoder.fromWireToProtoObj(bytes);
+          const result = (await decoder.fromProtoObj(
+            pubSubTopic,
+            protoResult!
+          )) as DecodedMessage;
+
+          expect(result.isMetaValid()).to.be.true;
+        }
+      )
+    );
+  });
 });
diff --git a/packages/core/src/lib/message/version_0.ts b/packages/core/src/lib/message/version_0.ts
@@ -1,4 +1,4 @@
-import { IMetaSetter } from "@waku/interfaces";
+import { IMetaSetter, IMetaValidator } from "@waku/interfaces";
 import type {
   EncoderOptions,
   IDecodedMessage,
@@ -11,14 +11,20 @@ import type {
 import { proto_message as proto } from "@waku/proto";
 import debug from "debug";
 
+import { toProtoMessage } from "../to_proto_message.js";
+
 const log = debug("waku:message:version-0");
 const OneMillion = BigInt(1_000_000);
 
 export const Version = 0;
 export { proto };
 
 export class DecodedMessage implements IDecodedMessage {
-  constructor(public pubSubTopic: string, protected proto: proto.WakuMessage) {}
+  constructor(
+    public pubSubTopic: string,
+    protected proto: proto.WakuMessage,
+    private metaValidator: IMetaValidator
+  ) {}
 
   get ephemeral(): boolean {
     return Boolean(this.proto.ephemeral);
@@ -64,6 +70,10 @@ export class DecodedMessage implements IDecodedMessage {
   get rateLimitProof(): IRateLimitProof | undefined {
     return this.proto.rateLimitProof;
   }
+
+  isMetaValid(): boolean {
+    return this.metaValidator(this.pubSubTopic, toProtoMessage(this.proto));
+  }
 }
 
 export class Encoder implements IEncoder {
@@ -117,7 +127,10 @@ export function createEncoder({
 }
 
 export class Decoder implements IDecoder<DecodedMessage> {
-  constructor(public contentTopic: string) {}
+  constructor(
+    public contentTopic: string,
+    protected metaValidator?: IMetaValidator
+  ) {}
 
   fromWireToProtoObj(bytes: Uint8Array): Promise<IProtoMessage | undefined> {
     const protoMessage = proto.WakuMessage.decode(bytes);
@@ -149,7 +162,8 @@ export class Decoder implements IDecoder<DecodedMessage> {
       return Promise.resolve(undefined);
     }
 
-    return new DecodedMessage(pubSubTopic, proto);
+    const metaValidator = this.metaValidator ?? (() => true);
+    return new DecodedMessage(pubSubTopic, proto, metaValidator);
   }
 }
 
@@ -163,7 +177,11 @@ export class Decoder implements IDecoder<DecodedMessage> {
  * messages.
  *
  * @param contentTopic The resulting decoder will only decode messages with this content topic.
+ * @param metaValidator Validator to use to verify meta field.
  */
-export function createDecoder(contentTopic: string): Decoder {
-  return new Decoder(contentTopic);
+export function createDecoder(
+  contentTopic: string,
+  metaValidator?: IMetaValidator
+): Decoder {
+  return new Decoder(contentTopic, metaValidator);
 }
diff --git a/packages/interfaces/src/message.ts b/packages/interfaces/src/message.ts
@@ -58,13 +58,25 @@ export interface IEncoder {
   toProtoObj: (message: IMessage) => Promise<IProtoMessage | undefined>;
 }
 
+export interface IMetaValidator {
+  /**
+   * Used to validate the `meta` field of a message.
+   */
+  (pubSubTopic: string, message: IProtoMessage): boolean;
+}
+
 export interface IDecodedMessage {
   payload: Uint8Array;
   contentTopic: string;
   pubSubTopic: string;
   timestamp: Date | undefined;
   rateLimitProof: IRateLimitProof | undefined;
   ephemeral: boolean | undefined;
+  /**
+   * Calls the { @link @waku/interface.message.IMetaValidator } passed on the
+   * decoder. Returns true if no meta validator is passed.
+   */
+  isMetaValid: () => boolean;
 }
 
 export interface IDecoder<T extends IDecodedMessage> {

diff --git a/packages/message-encryption/src/decoded_message.ts b/packages/message-encryption/src/decoded_message.ts
@@ -2,7 +2,7 @@ import {
   DecodedMessage as DecodedMessageV0,
   proto,
 } from "@waku/core/lib/message/version_0";
-import type { IDecodedMessage } from "@waku/interfaces";
+import type { IDecodedMessage, IMetaValidator } from "@waku/interfaces";
 
 export class DecodedMessage
   extends DecodedMessageV0
@@ -14,10 +14,11 @@ export class DecodedMessage
     pubSubTopic: string,
     proto: proto.WakuMessage,
     decodedPayload: Uint8Array,
+    metaValidator: IMetaValidator,
     public signature?: Uint8Array,
     public signaturePublicKey?: Uint8Array
   ) {
-    super(pubSubTopic, proto);
+    super(pubSubTopic, proto, metaValidator);
     this._decodedPayload = decodedPayload;
   }
 

diff --git a/packages/message-encryption/src/ecies.spec.ts b/packages/message-encryption/src/ecies.spec.ts
@@ -1,3 +1,4 @@
+import { DecodedMessage } from "@waku/core";
 import { IProtoMessage } from "@waku/interfaces";
 import { expect } from "chai";
 import fc from "fast-check";
@@ -129,4 +130,116 @@ describe("Ecies Encryption", function () {
       )
     );
   });
+
+  it("isMetaValid returns true when no meta validator is specified [ecies]", async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.string(),
+        fc.string(),
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ min: 1, minLength: 32, maxLength: 32 }),
+        async (pubSubTopic, contentTopic, payload, privateKey) => {
+          const publicKey = getPublicKey(privateKey);
+          const encoder = createEncoder({
+            contentTopic,
+            publicKey,
+          });
+          const bytes = await encoder.toWire({ payload });
+
+          const decoder = createDecoder(contentTopic, privateKey);
+          const protoResult = await decoder.fromWireToProtoObj(bytes!);
+          if (!protoResult) throw "Failed to proto decode";
+          const result = await decoder.fromProtoObj(pubSubTopic, protoResult);
+          if (!result) throw "Failed to decode";
+
+          expect(result.isMetaValid()).to.be.true;
+        }
+      )
+    );
+  });
+
+  it("isMetaValid returns false when validator specified returns false [ecies]", async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.string(),
+        fc.string(),
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ min: 1, minLength: 32, maxLength: 32 }),
+        async (pubSubTopic, contentTopic, payload, privateKey) => {
+          const publicKey = getPublicKey(privateKey);
+          const encoder = createEncoder({
+            contentTopic,
+            publicKey,
+          });
+          const bytes = await encoder.toWire({ payload });
+
+          const decoder = createDecoder(contentTopic, privateKey, () => false);
+          const protoResult = await decoder.fromWireToProtoObj(bytes!);
+          if (!protoResult) throw "Failed to proto decode";
+          const result = await decoder.fromProtoObj(pubSubTopic, protoResult);
+          if (!result) throw "Failed to decode";
+
+          expect(result.isMetaValid()).to.be.false;
+        }
+      )
+    );
+  });
+
+  it("isMetaValid returns true when matching meta setter [ecies]", async function () {
+    await fc.assert(
+      fc.asyncProperty(
+        fc.string(),
+        fc.string(),
+        fc.uint8Array({ minLength: 1 }),
+        fc.uint8Array({ min: 1, minLength: 32, maxLength: 32 }),
+        async (pubSubTopic, contentTopic, payload, privateKey) => {
+          const publicKey = getPublicKey(privateKey);
+          const metaSetter = (
+            msg: IProtoMessage & { meta: undefined }
+          ): Uint8Array => {
+            const buffer = new ArrayBuffer(4);
+            const view = new DataView(buffer);
+            view.setUint32(0, msg.payload.length);
+            return new Uint8Array(buffer);
+          };
+
+          const encoder = createEncoder({
+            contentTopic,
+            publicKey,
+            metaSetter,
+          });
+
+          const metaValidator = (
+            _pubSubTopic: string,
+            message: IProtoMessage
+          ): boolean => {
+            if (!message.meta) return false;
+
+            const view = new DataView(
+              message.meta.buffer,
+              message.meta.byteOffset,
+              4
+            );
+            const metaInt = view.getUint32(0);
+
+            return metaInt === message.payload.length;
+          };
+          const decoder = createDecoder(
+            contentTopic,
+            privateKey,
+            metaValidator
+          );
+
+          const bytes = await encoder.toWire({ payload });
+          const protoResult = await decoder.fromWireToProtoObj(bytes!);
+          const result = (await decoder.fromProtoObj(
+            pubSubTopic,
+            protoResult!
+          )) as DecodedMessage;
+
+          expect(result.isMetaValid()).to.be.true;
+        }
+      )
+    );
+  });
 });