save last sent CHLO in client CryptoSetup

handshake/crypto_setup_client.go

@@ -26,6 +26,7 @@ type cryptoSetupClient struct {
 	sno                  []byte
 	nonc                 []byte
 	diversificationNonce []byte
+	lastSentCHLO         []byte
 	certManager          *crypto.CertManager
 }
 
@@ -168,6 +169,9 @@ func (h *cryptoSetupClient) sendCHLO() error {
 	if err != nil {
 		return err
 	}
+
+	h.lastSentCHLO = b.Bytes()
+
 	return nil
 }
 

handshake/crypto_setup_client_test.go

@@ -122,6 +122,21 @@ var _ = Describe("Crypto setup", func() {
 			Expect(cs.cryptoStream.(*mockStream).dataWritten.Len()).To(BeNumerically(">", protocol.ClientHelloMinimumSize))
 		})
 
+		It("saves the last sent CHLO", func() {
+			// send first CHLO
+			err := cs.sendCHLO()
+			Expect(err).ToNot(HaveOccurred())
+			Expect(cs.cryptoStream.(*mockStream).dataWritten.Bytes()).To(Equal(cs.lastSentCHLO))
+			cs.cryptoStream.(*mockStream).dataWritten.Reset()
+			firstCHLO := cs.lastSentCHLO
+			// send second CHLO
+			cs.sno = []byte("foobar")
+			err = cs.sendCHLO()
+			Expect(err).ToNot(HaveOccurred())
+			Expect(cs.cryptoStream.(*mockStream).dataWritten.Bytes()).To(Equal(cs.lastSentCHLO))
+			Expect(cs.lastSentCHLO).ToNot(Equal(firstCHLO))
+		})
+
 		It("has the right values for an inchoate CHLO", func() {
 			tags := cs.getTags()
 			Expect(tags).To(HaveKey(TagSNI))