implement source address token generation and validation

ref #121

crypto/source_address_token_test.go

@@ -0,0 +1,112 @@
+package crypto
+
+import (
+	"net"
+	"time"
+
+	"github.com/lucas-clemente/quic-go/protocol"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Source Address Tokens", func() {
+	It("should generate the encryption key", func() {
+		Expect(deriveKey([]byte("TESTING"))).To(Equal([]byte{0xee, 0x71, 0x18, 0x9, 0xfd, 0xb8, 0x9a, 0x79, 0x19, 0xfc, 0x5e, 0x1a, 0x97, 0x20, 0xb2, 0x6}))
+	})
+
+	Context("tokens", func() {
+		It("serializes", func() {
+			ip := []byte{127, 0, 0, 1}
+			token := &sourceAddressToken{ip: ip, timestamp: 0xdeadbeef}
+			Expect(token.serialize()).To(Equal([]byte{
+				0xef, 0xbe, 0xad, 0xde, 0x00, 0x00, 0x00, 0x00,
+				127, 0, 0, 1,
+			}))
+		})
+
+		It("reads", func() {
+			token, err := parseToken([]byte{
+				0xef, 0xbe, 0xad, 0xde, 0x00, 0x00, 0x00, 0x00,
+				127, 0, 0, 1,
+			})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(token.ip).To(Equal(net.IP{127, 0, 0, 1}))
+			Expect(token.timestamp).To(Equal(uint64(0xdeadbeef)))
+		})
+	})
+
+	Context("source", func() {
+		var (
+			source *stkSource
+			secret []byte
+			ip4    net.IP
+			ip6    net.IP
+		)
+
+		BeforeEach(func() {
+			var err error
+
+			ip4 = net.ParseIP("1.2.3.4")
+			Expect(ip4).NotTo(BeEmpty())
+			ip6 = net.ParseIP("2001:0db8:0000:0000:0000:ff00:0042:8329")
+			Expect(ip6).NotTo(BeEmpty())
+
+			secret = []byte("TESTING")
+			source, err = newStkSource(secret)
+			Expect(err).NotTo(HaveOccurred())
+		})
+
+		It("should generate new tokens", func() {
+			token, err := source.NewToken(ip4)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(token).ToNot(BeEmpty())
+		})
+
+		It("should generate and verify ipv4 tokens", func() {
+			stk, err := source.NewToken(ip4)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(stk).ToNot(BeEmpty())
+			err = source.VerifyToken(ip4, stk)
+			Expect(err).NotTo(HaveOccurred())
+		})
+
+		It("should generate and verify ipv6 tokens", func() {
+			stk, err := source.NewToken(ip6)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(stk).ToNot(BeEmpty())
+			err = source.VerifyToken(ip6, stk)
+			Expect(err).NotTo(HaveOccurred())
+		})
+
+		It("should reject empty tokens", func() {
+			err := source.VerifyToken(ip4, nil)
+			Expect(err).To(HaveOccurred())
+		})
+
+		It("should reject invalid tokens", func() {
+			err := source.VerifyToken(ip4, []byte("foobar"))
+			Expect(err).To(HaveOccurred())
+		})
+
+		It("should reject outdated tokens", func() {
+			stk, err := encryptToken(source.aead, &sourceAddressToken{
+				ip:        ip4,
+				timestamp: uint64(time.Now().Unix() - protocol.STKExpiryTimeSec - 1),
+			})
+			Expect(err).NotTo(HaveOccurred())
+			err = source.VerifyToken(ip4, stk)
+			Expect(err).To(MatchError("STK expired"))
+		})
+
+		It("should reject tokens with wrong IP addresses", func() {
+			otherIP := net.ParseIP("4.3.2.1")
+			stk, err := encryptToken(source.aead, &sourceAddressToken{
+				ip:        otherIP,
+				timestamp: uint64(time.Now().Unix()),
+			})
+			Expect(err).NotTo(HaveOccurred())
+			err = source.VerifyToken(ip4, stk)
+			Expect(err).To(MatchError("invalid ip in STK"))
+		})
+	})
+})