Initial end-to-end tests, failing atm...

sphinx_test.go

@@ -1,6 +1,88 @@
 package main
 
-import "testing"
+import (
+	"bytes"
+	"testing"
+
+	"github.com/btcsuite/btcd/btcec"
+	"github.com/btcsuite/btcd/chaincfg"
+)
 
 func TestSphinxCorrectness(t *testing.T) {
+	nodes := make([]*SphinxNode, numMaxHops)
+
+	// Create numMaxHops random sphinx nodes.
+	for i := 0; i < len(nodes); i++ {
+		privKey, err := btcec.NewPrivateKey(btcec.S256())
+		if err != nil {
+			t.Fatalf("Unable to generate random key for sphinx node: %v", err)
+		}
+
+		nodes[i] = NewSphinxNode(privKey, &chaincfg.MainNetParams)
+	}
+
+	// Gather all the pub keys in the path.
+	route := make([]*btcec.PublicKey, len(nodes))
+	for i := 0; i < len(nodes); i++ {
+		route[i] = nodes[i].lnKey.PubKey()
+	}
+
+	// Generate a forwarding message to route to the final node via the
+	// generated intermdiates nodes above.
+	fwdMsg, err := NewForwardingMessage(route, []byte("roasbeef"), []byte("testing"))
+	if err != nil {
+		t.Fatalf("Unable to create forwarding message: %#v", err)
+	}
+
+	// TODO(roasbeef): assert proper nodeID of first hop
+
+	// Now simulate the message propagating through the mix net eventually
+	// reaching the final destination.
+	for i := 0; i < len(nodes); i++ {
+		hop := nodes[i]
+
+		processAction, err := hop.ProcessForwardingMessage(fwdMsg)
+		if err != nil {
+			t.Fatalf("Node %v was unabled to process the forwarding message: %v", i, err)
+		}
+
+		// If this is the last hop on the path, the node should
+		// recognize that it's the exit node.
+		if i == len(nodes)-1 {
+			if processAction.action != ExitNode {
+				t.Fatalf("Processing error, node %v is the last hop in"+
+					"the path, yet it doesn't recognize so", i)
+			}
+
+			// The original destination address and message should
+			// now be fully decrypted.
+			if !bytes.Equal([]byte("roasbeef"), processAction.destAddr) {
+				t.Fatalf("Message parsed incorrectly at final destination!"+
+					"Should be %v, is instead %v",
+					[]byte("roasbeef"), processAction.destAddr)
+			}
+
+			if !bytes.HasPrefix([]byte("testing"), processAction.destMsg) {
+				t.Fatalf("Dest addr parsed incorrectly at final destination!"+
+					"Should be %v, is instead %v",
+					[]byte("testing"), processAction.destMsg)
+			}
+
+		} else if processAction.action != MoreHops {
+			// If this isn't the last node in the path, then the returned
+			// action should indicate that there are more hops to go.
+			t.Fatalf("Processing error, node %v is not the final"+
+				" hop, yet thinks it is.", i)
+		}
+
+		// The next hop should have been parsed as node[i+1].
+		parsedNextHop := processAction.fwdMsg.Header.RoutingInfo[:securityParameter]
+		if !bytes.Equal(parsedNextHop, nodes[i+1].nodeID[:]) {
+			t.Fatalf("Processing error, next hop parsed incorrectly."+
+				" next hop shoud be %v, was instead parsed as %v",
+				nodes[i+1].nodeID[:], parsedNextHop)
+		}
+
+		fwdMsg = processAction.fwdMsg
+	}
 }