KYBER768 KEM works. :O

hkexnet/hkexchan.go

@@ -19,7 +19,6 @@ import (
 	"fmt"
 	"hash"
 	"log"
-	"math/big"
 
 	"golang.org/x/crypto/blowfish"
 	"golang.org/x/crypto/twofish"
@@ -33,7 +32,7 @@ import (
 /* Support functionality to set up encryption after a channel has
 been negotiated via hkexnet.go
 */
-func (hc Conn) getStream(keymat *big.Int) (rc cipher.Stream, mc hash.Hash, err error) {
+func (hc Conn) getStream(keymat []byte) (rc cipher.Stream, mc hash.Hash, err error) {
 	var key []byte
 	var block cipher.Block
 	var iv []byte
@@ -44,23 +43,23 @@ func (hc Conn) getStream(keymat *big.Int) (rc cipher.Stream, mc hash.Hash, err e
 	// is >= 2*cipher.BlockSize (enough for both key and iv)
 	switch copts {
 	case CAlgAES256:
-		key = keymat.Bytes()[0:aes.BlockSize]
+		key = keymat[0:aes.BlockSize]
 		block, err = aes.NewCipher(key)
 		ivlen = aes.BlockSize
-		iv = keymat.Bytes()[aes.BlockSize : aes.BlockSize+ivlen]
+		iv = keymat[aes.BlockSize : aes.BlockSize+ivlen]
 		rc = cipher.NewOFB(block, iv)
 		log.Printf("[cipher AES_256 (%d)]\n", copts)
 		break
 	case CAlgTwofish128:
-		key = keymat.Bytes()[0:twofish.BlockSize]
+		key = keymat[0:twofish.BlockSize]
 		block, err = twofish.NewCipher(key)
 		ivlen = twofish.BlockSize
-		iv = keymat.Bytes()[twofish.BlockSize : twofish.BlockSize+ivlen]
+		iv = keymat[twofish.BlockSize : twofish.BlockSize+ivlen]
 		rc = cipher.NewOFB(block, iv)
 		log.Printf("[cipher TWOFISH_128 (%d)]\n", copts)
 		break
 	case CAlgBlowfish64:
-		key = keymat.Bytes()[0:blowfish.BlockSize]
+		key = keymat[0:blowfish.BlockSize]
 		block, err = blowfish.NewCipher(key)
 		ivlen = blowfish.BlockSize
 		// N.b. Bounds enforcement of differing cipher algorithms
@@ -72,7 +71,7 @@ func (hc Conn) getStream(keymat *big.Int) (rc cipher.Stream, mc hash.Hash, err e
 		//
 		// I assume the other two check bounds and only
 		// copy what's needed whereas blowfish does no such check.
-		iv = keymat.Bytes()[blowfish.BlockSize : blowfish.BlockSize+ivlen]
+		iv = keymat[blowfish.BlockSize : blowfish.BlockSize+ivlen]
 		rc = cipher.NewOFB(block, iv)
 		log.Printf("[cipher BLOWFISH_64 (%d)]\n", copts)
 		break

hkexnet/hkexnet.go

@@ -46,6 +46,7 @@ import (
 	"time"
 
 	"blitter.com/go/hkexsh/herradurakex"
+	kyber "git.schwanenlied.me/yawning/kyber.git"
 )
 
 /*---------------------------------------------------------------------*/
@@ -171,12 +172,14 @@ func _new(kexAlg KEXAlg, conn *net.Conn) (hc *Conn, e error) {
 	// Set up KEx/KEM-specifics
 	switch hc.kex {
 	case KEX_HERRADURA:
-	default:
-		return hc, HKExAcceptSetup(hc.c, hc)
+		return hc, nil //HKExAcceptSetup(hc.c, hc)
 		log.Printf("[KEx alg %d accepted]\n", kexAlg)
 	case KEX_KYBER768:
-		fmt.Println("KYBER768: TODO")
-		return nil, errors.New("KEx Setup failed")
+		return hc, nil //Kyber768AcceptSetup(hc.c, hc)
+		log.Printf("[KEx alg %d accepted]\n", kexAlg)
+	default:
+		return hc, nil //HKExAcceptSetup(hc.c, hc)
+		log.Printf("[KEx alg %d accepted]\n", kexAlg)
 	}
 	return
 }
@@ -222,8 +225,53 @@ func (hc *Conn) applyConnExtensions(extensions ...string) {
 	}
 }
 
+// randReader wraps rand.Read() in a struct that implements io.Reader
+// for use by the Kyber KEM methods.
+type randReader struct {
+}
+
+func (r randReader) Read(b []byte) (n int, e error) {
+	n, e = rand.Read(b)
+	return
+}
+
 func Kyber768DialSetup(c net.Conn, hc *Conn) (err error) {
-	return errors.New("NOT IMPLEMENTED")
+	//h := hkex.New(0, 0)
+	// Send hkexnet.Conn parameters to remote side
+
+	// Alice, step 1: Generate a key pair.
+	r := new(randReader)
+	alicePublicKey, alicePrivateKey, err := kyber.Kyber768.GenerateKeyPair(r)
+	if err != nil {
+		panic(err)
+	}
+
+	// Alice, step 2: Send the public key to Bob
+	fmt.Fprintf(c, "0x%x\n%08x:%08x\n", alicePublicKey.Bytes(),
+		hc.cipheropts, hc.opts)
+
+	// [Bob, step 1-3], from which we read cipher text
+	b := big.NewInt(0)
+	_, err = fmt.Fscanln(c, b)
+	if err != nil {
+		return err
+	}
+	log.Printf("[Got server ciphertext:0x%x]\n", b.Bytes())
+
+	// Read cipheropts, session opts
+	_, err = fmt.Fscanf(c, "%08x:%08x\n",
+		&hc.cipheropts, &hc.opts)
+	if err != nil {
+		return err
+	}
+
+	// Alice, step 3: Decrypt the KEM cipher text.
+	aliceSharedSecret := alicePrivateKey.KEMDecrypt(b.Bytes())
+
+	log.Printf("[Derived sharedSecret:0x%x]\n", aliceSharedSecret)
+	hc.r, hc.rm, err = hc.getStream(aliceSharedSecret)
+	hc.w, hc.wm, err = hc.getStream(aliceSharedSecret)
+	return
 }
 
 func HKExDialSetup(c net.Conn, hc *Conn) (err error) {
@@ -251,13 +299,47 @@ func HKExDialSetup(c net.Conn, hc *Conn) (err error) {
 	h.ComputeFA()
 	log.Printf("**(c)** FA:%s\n", h.FA())
 
-	hc.r, hc.rm, err = hc.getStream(h.FA())
-	hc.w, hc.wm, err = hc.getStream(h.FA())
+	hc.r, hc.rm, err = hc.getStream(h.FA().Bytes())
+	hc.w, hc.wm, err = hc.getStream(h.FA().Bytes())
 	return
 }
 
 func Kyber768AcceptSetup(c *net.Conn, hc *Conn) (err error) {
-	return errors.New("NOT IMPLEMENTED")
+	//h := hkex.New(0, 0)
+	// Bob, step 1: Deserialize Alice's public key from the binary encoding.
+	alicePublicKey := big.NewInt(0)
+	_, err = fmt.Fscanln(*c, alicePublicKey)
+	log.Printf("[Got client pubKey:0x%x\n]", alicePublicKey)
+	if err != nil {
+		return err
+	}
+	_, err = fmt.Fscanf(*c, "%08x:%08x\n",
+		&hc.cipheropts, &hc.opts)
+	log.Printf("[Got cipheropts, opts:%v, %v]", hc.cipheropts, hc.opts)
+	if err != nil {
+		return err
+	}
+
+	peerPublicKey, err := kyber.Kyber768.PublicKeyFromBytes(alicePublicKey.Bytes())
+	if err != nil {
+		panic(err)
+	}
+
+	// Bob, step 2: Generate the KEM cipher text and shared secret.
+	r := new(randReader)
+	cipherText, bobSharedSecret, err := peerPublicKey.KEMEncrypt(r)
+	if err != nil {
+		panic(err)
+	}
+
+	// Bob, step 3: Send the cipher text to Alice (Not shown).
+	fmt.Fprintf(*c, "0x%x\n%08x:%08x\n", cipherText,
+		hc.cipheropts, hc.opts)
+
+	log.Printf("[Derived sharedSecret:0x%x]\n", bobSharedSecret)
+	hc.r, hc.rm, err = hc.getStream(bobSharedSecret)
+	hc.w, hc.wm, err = hc.getStream(bobSharedSecret)
+	return
 }
 
 func HKExAcceptSetup(c *net.Conn, hc *Conn) (err error) {
@@ -286,8 +368,8 @@ func HKExAcceptSetup(c *net.Conn, hc *Conn) (err error) {
 	fmt.Fprintf(*c, "0x%s\n%08x:%08x\n", h.D().Text(16),
 		hc.cipheropts, hc.opts)
 
-	hc.r, hc.rm, err = hc.getStream(h.FA())
-	hc.w, hc.wm, err = hc.getStream(h.FA())
+	hc.r, hc.rm, err = hc.getStream(h.FA().Bytes())
+	hc.w, hc.wm, err = hc.getStream(h.FA().Bytes())
 	return
 }
 

hkexsh/hkexsh.go

@@ -351,8 +351,9 @@ func main() {
 	var gopt bool //login via password, asking server to generate authToken
 	var dbg bool
 	var shellMode bool // if true act as shell, else file copier
-	var cAlg string
-	var hAlg string
+	var cAlg string    //cipher alg
+	var hAlg string    //hmac alg
+	var kAlg string    //KEX/KEM alg
 	var server string
 	var port uint
 	var cmdStr string
@@ -373,6 +374,7 @@ func main() {
 	flag.BoolVar(&dbg, "d", false, "debug logging")
 	flag.StringVar(&cAlg, "c", "C_AES_256", "`cipher` [\"C_AES_256\" | \"C_TWOFISH_128\" | \"C_BLOWFISH_64\"]")
 	flag.StringVar(&hAlg, "m", "H_SHA256", "`hmac` [\"H_SHA256\"]")
+	flag.StringVar(&kAlg, "k", "KEX_HERRADURA", "`kex` [\"KEX_HERRADURA\" | \"KEX_KYBER768\"]")
 	flag.UintVar(&port, "p", 2000, "`port`")
 	//flag.StringVar(&authCookie, "a", "", "auth cookie")
 	flag.BoolVar(&chaffEnabled, "e", true, "enabled chaff pkts (default true)")
@@ -543,7 +545,7 @@ func main() {
 		}
 	}
 
-	conn, err := hkexnet.Dial("tcp", server, "KEX_HERRADURA", cAlg, hAlg)
+	conn, err := hkexnet.Dial("tcp", server, cAlg, hAlg, kAlg)
 	if err != nil {
 		fmt.Println(err)
 		panic(err)