Add Cosmos Hub (ATOM) support

Closes #452, thanks @conr2d

src/index.html

@@ -1101,6 +1101,7 @@
         <script src="js/ripple-util.js"></script>
         <script src="js/jingtum-util.js"></script>
         <script src="js/casinocoin-util.js"></script>
+        <script src="js/cosmos-util.js"></script>
         <script src="js/eos-util.js"></script>
         <script src="js/fio-util.js"></script>
         <script src="js/sjcl-bip39.js"></script>

src/js/cosmos-util.js

@@ -0,0 +1,13 @@
+function CosmosBufferToPublic(pubBuf) {
+  const Buffer = libs.buffer.Buffer;
+  const AminoSecp256k1PubkeyPrefix = Buffer.from("EB5AE987", "hex");
+  const AminoSecp256k1PubkeyLength = Buffer.from("21", "hex");
+  pubBuf = Buffer.concat([AminoSecp256k1PubkeyPrefix, AminoSecp256k1PubkeyLength, pubBuf]);
+  return libs.bech32.encode("cosmospub", libs.bech32.toWords(pubBuf));
+}
+
+function CosmosBufferToAddress(pubBuf) {
+  const sha256_ed = libs.createHash("sha256").update(pubBuf).digest();
+  const ripemd160_ed = libs.createHash("rmd160").update(sha256_ed).digest();
+  return libs.bech32.encode("cosmos", libs.bech32.toWords(ripemd160_ed));
+}

src/js/index.js

@@ -1419,6 +1419,12 @@
                     privkey = FIObufferToPrivate(keyPair.d.toBuffer(32));
                 }
 
+                if (networks[DOM.network.val()].name == "ATOM - Cosmos Hub") {
+                    address = CosmosBufferToAddress(keyPair.getPublicKeyBuffer());
+                    pubkey = CosmosBufferToPublic(keyPair.getPublicKeyBuffer());
+                    privkey = keyPair.d.toBuffer().toString("base64");
+                }
+
                 //Groestlcoin Addresses are different
                 if(isGRS()) {
 
@@ -2234,6 +2240,13 @@
                 setHdCoin(357);
             },
         },
+        {
+            name: "ATOM - Cosmos Hub",
+            onSelect: function() {
+                network = libs.bitcoin.networks.bitcoin;
+                setHdCoin(118);
+            },
+        },
         {
             name: "AUR - Auroracoin",
             onSelect: function() {