From eb1d60f2c0c9e41fa148f7e9791732113e11dd00 Mon Sep 17 00:00:00 2001
From: George Tankersley <george.tankersley@gmail.com>
Date: Wed, 9 Oct 2019 23:25:01 -0400
Subject: [PATCH] merlin: add complex protocol test from dalek merlin

---
 merlin.go      |  4 +++-
 merlin_test.go | 24 ++++++++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/merlin.go b/merlin.go
index 6ec5061..bdafa80 100644
--- a/merlin.go
+++ b/merlin.go
@@ -63,5 +63,7 @@ func (t *Transcript) ExtractBytes(label []byte, outLen int) []byte {
 	t.s.AD(true, labelSize)
 
 	// a PRF call directly to the output buffer would be better
-	return t.s.PRF(outLen)
+	outBytes := t.s.PRF(outLen)
+	fmt.Printf("PRF : %x\n", outBytes)
+	return outBytes
 }
diff --git a/merlin_test.go b/merlin_test.go
index 6cd2e87..4499f9f 100644
--- a/merlin_test.go
+++ b/merlin_test.go
@@ -26,3 +26,27 @@ func TestSimpleTranscript(t *testing.T) {
 		t.Errorf("\nGot : %s\nWant: %s", cHex, expectedHex)
 	}
 }
+
+func TestComplexTranscript(t *testing.T) {
+	tr := NewTranscript("test protocol")
+	tr.AppendMessage([]byte("step1"), []byte("some data"))
+
+	data := make([]byte, 1024)
+	for i := range data {
+		data[i] = 99
+	}
+
+	var chlBytes []byte
+	for i := 0; i < 32; i++ {
+		chlBytes = tr.ExtractBytes([]byte("challenge"), 32)
+		tr.AppendMessage([]byte("bigdata"), data)
+		tr.AppendMessage([]byte("challengedata"), chlBytes)
+	}
+
+	expectedChlHex := "a8c933f54fae76e3f9bea93648c1308e7dfa2152dd51674ff3ca438351cf003c"
+	chlHex := fmt.Sprintf("%x", chlBytes)
+
+	if chlHex != expectedChlHex {
+		t.Errorf("\nGot : %s\nWant: %s", chlHex, expectedChlHex)
+	}
+}