connect to ext clients using proxy

nm-proxy/packet/utils.go

@@ -0,0 +1,98 @@
+package packet
+
+import (
+	"crypto/hmac"
+	"crypto/subtle"
+	"hash"
+
+	"github.com/gravitl/netmaker/nm-proxy/wg"
+	"golang.org/x/crypto/blake2s"
+	"golang.org/x/crypto/curve25519"
+)
+
+const (
+	MessageInitiationType = 1
+
+	NoisePublicKeySize  = 32
+	NoisePrivateKeySize = 32
+
+	NoiseConstruction = "Noise_IKpsk2_25519_ChaChaPoly_BLAKE2s"
+	WGIdentifier      = "WireGuard v1 zx2c4 Jason@zx2c4.com"
+	WGLabelMAC1       = "mac1----"
+	WGLabelCookie     = "cookie--"
+)
+
+func mixKey(dst, c *[blake2s.Size]byte, data []byte) {
+	KDF1(dst, c[:], data)
+}
+
+func mixHash(dst, h *[blake2s.Size]byte, data []byte) {
+	hash, _ := blake2s.New256(nil)
+	hash.Write(h[:])
+	hash.Write(data)
+	hash.Sum(dst[:0])
+	hash.Reset()
+}
+func HMAC1(sum *[blake2s.Size]byte, key, in0 []byte) {
+	mac := hmac.New(func() hash.Hash {
+		h, _ := blake2s.New256(nil)
+		return h
+	}, key)
+	mac.Write(in0)
+	mac.Sum(sum[:0])
+}
+
+func HMAC2(sum *[blake2s.Size]byte, key, in0, in1 []byte) {
+	mac := hmac.New(func() hash.Hash {
+		h, _ := blake2s.New256(nil)
+		return h
+	}, key)
+	mac.Write(in0)
+	mac.Write(in1)
+	mac.Sum(sum[:0])
+}
+
+func KDF1(t0 *[blake2s.Size]byte, key, input []byte) {
+	HMAC1(t0, key, input)
+	HMAC1(t0, t0[:], []byte{0x1})
+}
+
+func KDF2(t0, t1 *[blake2s.Size]byte, key, input []byte) {
+	var prk [blake2s.Size]byte
+	HMAC1(&prk, key, input)
+	HMAC1(t0, prk[:], []byte{0x1})
+	HMAC2(t1, prk[:], t0[:], []byte{0x2})
+	setZero(prk[:])
+}
+
+func setZero(arr []byte) {
+	for i := range arr {
+		arr[i] = 0
+	}
+}
+func isZero(val []byte) bool {
+	acc := 1
+	for _, b := range val {
+		acc &= subtle.ConstantTimeByteEq(b, 0)
+	}
+	return acc == 1
+}
+
+func GetDeviceKeys(ifaceName string) (NoisePrivateKey, NoisePublicKey, error) {
+	wgPrivKey := wg.GetWgIfacePrivKey(ifaceName)
+	wgPubKey := wg.GetWgIfacePubKey(ifaceName)
+
+	return wgPrivKey, wgPubKey, nil
+}
+
+type (
+	NoisePublicKey  [NoisePublicKeySize]byte
+	NoisePrivateKey [NoisePrivateKeySize]byte
+)
+
+func sharedSecret(sk *NoisePrivateKey, pk NoisePublicKey) (ss [NoisePublicKeySize]byte) {
+	apk := (*[NoisePublicKeySize]byte)(&pk)
+	ask := (*[NoisePrivateKeySize]byte)(sk)
+	curve25519.ScalarMult(&ss, ask, apk)
+	return ss
+}