Implement inv_vect, inv

README.md

@@ -14,7 +14,7 @@ API documentation is available [here](https://bitchan.github.io/bitmessage/docs/
 
 ## Feature matrix (both Browser and Node)
 
-- [x] crypto
+- [x] Crypto
   - [x] SHA-512
   - [x] SHA-256
   - [x] RIPEMD-160
@@ -31,6 +31,7 @@ API documentation is available [here](https://bitchan.github.io/bitmessage/docs/
   - [x] var_str
   - [x] var_int_list
   - [x] net_addr
+  - [x] inv_vect
   - [x] encrypted
   - [x] message encodings
   - [x] service features
@@ -39,7 +40,7 @@ API documentation is available [here](https://bitchan.github.io/bitmessage/docs/
   - [x] version
   - [x] verack
   - [x] addr
-  - [ ] inv
+  - [x] inv
   - [ ] getdata
   - [ ] error
   - [ ] object

lib/messages.js

@@ -12,7 +12,7 @@ var UserAgent = require("./user-agent");
 var util = require("./util");
 
 /**
- * Version message.
+ * `version` message.
  * @see {@link https://bitmessage.org/wiki/Protocol_specification#version}
  * @namespace
  */
@@ -99,7 +99,7 @@ exports.version = {
 };
 
 /**
- * Addresses message. Provide information on known nodes of the network.
+ * `addr` message. Provide information on known nodes of the network.
  * @see {@link https://bitmessage.org/wiki/Protocol_specification#addr}
  * @namespace
  */
@@ -138,3 +138,45 @@ exports.addr = {
     return Buffer.concat([structs.var_int.encode(addrs.length), addrsBuf]);
   },
 };
+
+/**
+ * `inv` message. Allows a node to advertise its knowledge of one or
+ * more objects.
+ * @see {@link https://bitmessage.org/wiki/Protocol_specification#inv}
+ * @namespace
+ */
+exports.inv = {
+  /**
+   * Decode `inv` payload.
+   * @param {Buffer} buf - Buffer that starts with encoded `inv` payload
+   * @return {Object} Decoded `inv` structure.
+   */
+  decode: function(buf) {
+    var decoded = structs.var_int.decode(buf);
+    var listLength = decoded.value;
+    assert(listLength <= 50000, "Too many inventory entires");
+    var length = decoded.length + listLength * 32;
+    assert(buf.length >= length, "Buffer is too small");
+    var rest = decoded.rest;
+    var inventory = new Array(listLength);
+    for (var i = 0; i < listLength; i++) {
+      inventory[i] = rest.slice(i*32, (i+1)*32);
+    }
+    return {
+      inventory: inventory,
+      // Real data length.
+      length: length,
+    };
+  },
+
+  /**
+   * Encode `inv` payload.
+   * @param {Buffer[]} inventory - Inventory vectors (encoded)
+   * @return {Buffer} Encoded `inv` payload.
+   */
+  encode: function(inventory) {
+    assert(inventory.length <= 50000, "Too many inventory entires");
+    var invBuf = Buffer.concat(inventory);
+    return Buffer.concat([structs.var_int.encode(inventory.length), invBuf]);
+  },
+};

lib/structs.js

@@ -417,6 +417,23 @@ exports.net_addr = {
   },
 };
 
+/**
+ * Inventory vector.
+ * @see {@link https://bitmessage.org/wiki/Protocol_specification#Inventory_Vectors}
+ * @namespace
+ */
+// Only encode operation is defined because decode is impossible.
+exports.inv_vect = {
+  /**
+   * Encode inventory vector.
+   * @param {Buffer} buf - Payload to calculate inventory vector for
+   * @return {Buffer} Encoded `inv_vect`.
+   */
+  encode: function(buf) {
+    return bmcrypto.sha512(bmcrypto.sha512(buf)).slice(0, 32);
+  },
+};
+
 var SECP256K1_TYPE = 714;
 
 /**

test.js

@@ -12,6 +12,7 @@ var var_int = structs.var_int;
 var var_str = structs.var_str;
 var var_int_list = structs.var_int_list;
 var net_addr = structs.net_addr;
+var inv_vect = structs.inv_vect;
 var encrypted = structs.encrypted;
 var messageEncodings = structs.messageEncodings;
 var serviceFeatures = structs.serviceFeatures;
@@ -19,6 +20,7 @@ var pubkeyFeatures = structs.pubkeyFeatures;
 var messages = bitmessage.messages;
 var version = messages.version;
 var addr = messages.addr;
+var inv = messages.inv;
 var WIF = bitmessage.WIF;
 var POW = bitmessage.POW;
 var Address = bitmessage.Address;
@@ -225,7 +227,13 @@ describe("Common structures", function() {
     });
   });
 
-  describe("Encrypted", function() {
+  describe("inv_vect", function() {
+    it("should encode", function() {
+      expect(inv_vect.encode("test").toString("hex")).to.equal("faadcaf60afd35dfcdb5e9ea0d0a0531f6338c62187cff37a1efe11f1d41a348");
+    });
+  });
+
+  describe("encrypted", function() {
     it("should encode and decode", function() {
       var iv = Buffer(16);
       var ephemPublicKey = Buffer(65);
@@ -249,7 +257,7 @@ describe("Common structures", function() {
     });
   });
 
-  describe("Message encodings", function() {
+  describe("message encodings", function() {
     it("should decode", function() {
       expect(messageEncodings.decode(Buffer([2])).value).to.equal(messageEncodings.SIMPLE);
     });
@@ -259,7 +267,7 @@ describe("Common structures", function() {
     });
   });
 
-  describe("Service features", function() {
+  describe("service features", function() {
     it("should decode", function() {
       expect(serviceFeatures.decode(Buffer("0000000000000001", "hex"))).to.have.members([serviceFeatures.NODE_NETWORK]);
     });
@@ -270,7 +278,7 @@ describe("Common structures", function() {
     });
   });
 
-  describe("Pubkey features", function() {
+  describe("pubkey features", function() {
     it("should decode", function() {
       expect(pubkeyFeatures.decode(Buffer("c0000000", "hex"))).to.have.members([pubkeyFeatures.DOES_ACK, pubkeyFeatures.INCLUDE_DESTINATION]);
     });
@@ -326,6 +334,24 @@ describe("Message types", function() {
       expect(addr.decode.bind(null, var_int.encode(2000))).to.throw(/too many/i);
     });
   });
+
+  describe("inv", function() {
+    it("should encode and decode", function() {
+      var vect1 = inv_vect.encode(Buffer("test"));
+      var vect2 = inv_vect.encode(Buffer("test2"));
+      var inventory = [vect1, vect2];
+      var res = inv.decode(inv.encode(inventory));
+      expect(res.inventory.length).to.equal(2);
+      expect(bufferEqual(res.inventory[0], vect1)).to.be.true;
+      expect(bufferEqual(res.inventory[1], vect2)).to.be.true;
+      expect(res.length).to.equal(65);
+    });
+
+    it("shouldn't encode/decode more than 1000 entires", function() {
+      expect(inv.encode.bind(null, Array(60000))).to.throw(/too many/i);
+      expect(inv.decode.bind(null, var_int.encode(60000))).to.throw(/too many/i);
+    });
+  });
 });
 
 describe("WIF", function() {