Improved cookie/mac computation code

1 files changed, 0 insertions, 270 deletions

diff --git a/src/macs.go b/src/macs.go
deleted file mode 100644
index d55e18f..0000000
--- a/src/macs.go
+++ /dev/null
@@ -1,270 +0,0 @@
-package main
-
-import (
-	"crypto/hmac"
-	"crypto/rand"
-	"golang.org/x/crypto/blake2s"
-	"net"
-	"sync"
-	"time"
-)
-
-type MACStateDevice struct {
-	mutex     sync.RWMutex
-	refreshed time.Time
-	secret    [blake2s.Size]byte
-	keyMAC1   [blake2s.Size]byte
-	keyMAC2   [blake2s.Size]byte // TODO: Change to more descriptive size constant, rename to something.
-}
-
-type MACStatePeer struct {
-	mutex       sync.RWMutex
-	cookieSet   time.Time
-	cookie      [blake2s.Size128]byte
-	lastMAC1Set bool
-	lastMAC1    [blake2s.Size128]byte
-	keyMAC1     [blake2s.Size]byte
-	keyMAC2     [blake2s.Size]byte
-}
-
-/* Methods for verifing MAC fields
- * and creating/consuming cookies replies
- * (per device)
- */
-
-func (state *MACStateDevice) Init(pk NoisePublicKey) {
-	state.mutex.Lock()
-	defer state.mutex.Unlock()
-
-	func() {
-		hsh, _ := blake2s.New256(nil)
-		hsh.Write([]byte(WGLabelMAC1))
-		hsh.Write(pk[:])
-		hsh.Sum(state.keyMAC1[:0])
-	}()
-
-	func() {
-		hsh, _ := blake2s.New256(nil)
-		hsh.Write([]byte(WGLabelCookie))
-		hsh.Write(pk[:])
-		hsh.Sum(state.keyMAC2[:0])
-	}()
-
-	state.refreshed = time.Time{}
-}
-
-func (state *MACStateDevice) CheckMAC1(msg []byte) bool {
-	size := len(msg)
-	startMac1 := size - (blake2s.Size128 * 2)
-	startMac2 := size - blake2s.Size128
-
-	var mac1 [blake2s.Size128]byte
-	func() {
-		mac, _ := blake2s.New128(state.keyMAC1[:])
-		mac.Write(msg[:startMac1])
-		mac.Sum(mac1[:0])
-	}()
-
-	return hmac.Equal(mac1[:], msg[startMac1:startMac2])
-}
-
-func (state *MACStateDevice) CheckMAC2(msg []byte, addr *net.UDPAddr) bool {
-	state.mutex.RLock()
-	defer state.mutex.RUnlock()
-
-	if time.Now().Sub(state.refreshed) > CookieRefreshTime {
-		return false
-	}
-
-	// derive cookie key
-
-	var cookie [blake2s.Size128]byte
-	func() {
-		port := [2]byte{byte(addr.Port >> 8), byte(addr.Port)}
-		mac, _ := blake2s.New128(state.secret[:])
-		mac.Write(addr.IP)
-		mac.Write(port[:]) // TODO: Be faster and more platform dependent?
-		mac.Sum(cookie[:0])
-	}()
-
-	// calculate mac of packet
-
-	start := len(msg) - blake2s.Size128
-
-	var mac2 [blake2s.Size128]byte
-	func() {
-		mac, _ := blake2s.New128(cookie[:])
-		mac.Write(msg[:start])
-		mac.Sum(mac2[:0])
-	}()
-
-	return hmac.Equal(mac2[:], msg[start:])
-}
-
-func (device *Device) CreateMessageCookieReply(
-	msg []byte, receiver uint32, addr *net.UDPAddr,
-) (*MessageCookieReply, error) {
-
-	state := &device.mac
-	state.mutex.RLock()
-
-	// refresh cookie secret
-
-	if time.Now().Sub(state.refreshed) > CookieRefreshTime {
-		state.mutex.RUnlock()
-		state.mutex.Lock()
-		_, err := rand.Read(state.secret[:])
-		if err != nil {
-			state.mutex.Unlock()
-			return nil, err
-		}
-		state.refreshed = time.Now()
-		state.mutex.Unlock()
-		state.mutex.RLock()
-	}
-
-	// derive cookie key
-
-	var cookie [blake2s.Size128]byte
-	func() {
-		port := [2]byte{byte(addr.Port >> 8), byte(addr.Port)}
-		mac, _ := blake2s.New128(state.secret[:])
-		mac.Write(addr.IP)
-		mac.Write(port[:]) // TODO: Do whatever we did above
-		mac.Sum(cookie[:0])
-	}()
-
-	// encrypt cookie
-
-	size := len(msg)
-
-	startMac1 := size - (blake2s.Size128 * 2)
-	startMac2 := size - blake2s.Size128
-
-	mac1 := msg[startMac1:startMac2]
-
-	reply := new(MessageCookieReply)
-	reply.Type = MessageCookieReplyType
-	reply.Receiver = receiver
-	_, err := rand.Read(reply.Nonce[:])
-	if err != nil {
-		state.mutex.RUnlock()
-		return nil, err
-	}
-
-	XChaCha20Poly1305Encrypt(
-		reply.Cookie[:0],
-		&reply.Nonce,
-		cookie[:],
-		mac1,
-		&state.keyMAC2,
-	)
-
-	state.mutex.RUnlock()
-	return reply, nil
-}
-
-func (device *Device) ConsumeMessageCookieReply(msg *MessageCookieReply) bool {
-
-	if msg.Type != MessageCookieReplyType {
-		return false
-	}
-
-	// lookup peer
-
-	lookup := device.indices.Lookup(msg.Receiver)
-	if lookup.handshake == nil {
-		return false
-	}
-
-	// decrypt and store cookie
-
-	var cookie [blake2s.Size128]byte
-	state := &lookup.peer.mac
-
-	state.mutex.Lock()
-	defer state.mutex.Unlock()
-
-	if !state.lastMAC1Set {
-		return false
-	}
-
-	_, err := XChaCha20Poly1305Decrypt(
-		cookie[:0],
-		&msg.Nonce,
-		msg.Cookie[:],
-		state.lastMAC1[:],
-		&state.keyMAC2,
-	)
-
-	if err != nil {
-		return false
-	}
-
-	state.cookieSet = time.Now()
-	state.cookie = cookie
-	return true
-}
-
-/* Methods for generating the MAC fields
- * (per peer)
- */
-
-func (state *MACStatePeer) Init(pk NoisePublicKey) {
-	state.mutex.Lock()
-	defer state.mutex.Unlock()
-
-	func() {
-		hsh, _ := blake2s.New256(nil)
-		hsh.Write([]byte(WGLabelMAC1))
-		hsh.Write(pk[:])
-		hsh.Sum(state.keyMAC1[:0])
-	}()
-
-	func() {
-		hsh, _ := blake2s.New256(nil)
-		hsh.Write([]byte(WGLabelCookie))
-		hsh.Write(pk[:])
-		hsh.Sum(state.keyMAC2[:0])
-	}()
-
-	state.cookieSet = time.Time{} // never
-}
-
-func (state *MACStatePeer) AddMacs(msg []byte) {
-	size := len(msg)
-
-	startMac1 := size - (blake2s.Size128 * 2)
-	startMac2 := size - blake2s.Size128
-
-	mac1 := msg[startMac1 : startMac1+blake2s.Size128]
-	mac2 := msg[startMac2 : startMac2+blake2s.Size128]
-
-	state.mutex.Lock()
-	defer state.mutex.Unlock()
-
-	// set mac1
-
-	func() {
-		mac, _ := blake2s.New128(state.keyMAC1[:])
-		mac.Write(msg[:startMac1])
-		mac.Sum(mac1[:0])
-	}()
-	copy(state.lastMAC1[:], mac1)
-	state.lastMAC1Set = true
-
-	// set mac2
-
-	if state.cookieSet.IsZero() {
-		return
-	}
-	if time.Now().Sub(state.cookieSet) > CookieRefreshTime {
-		state.cookieSet = time.Time{}
-		return
-	}
-	func() {
-		mac, _ := blake2s.New128(state.cookie[:])
-		mac.Write(msg[:startMac2])
-		mac.Sum(mac2[:0])
-	}()
-}