make handshake and crypto internal packages

internal/crypto/curve_25519_test.go

@@ -0,0 +1,27 @@
+package crypto
+
+import (
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("ProofRsa", func() {
+	It("works", func() {
+		a, err := NewCurve25519KEX()
+		Expect(err).ToNot(HaveOccurred())
+		b, err := NewCurve25519KEX()
+		Expect(err).ToNot(HaveOccurred())
+		sA, err := a.CalculateSharedKey(b.PublicKey())
+		Expect(err).ToNot(HaveOccurred())
+		sB, err := b.CalculateSharedKey(a.PublicKey())
+		Expect(err).ToNot(HaveOccurred())
+		Expect(sA).To(Equal(sB))
+	})
+
+	It("rejects short public keys", func() {
+		a, err := NewCurve25519KEX()
+		Expect(err).ToNot(HaveOccurred())
+		_, err = a.CalculateSharedKey(nil)
+		Expect(err).To(MatchError("Curve25519: expected public key of 32 byte"))
+	})
+})