wacky encryption

shared/crypto.go

@@ -1,36 +0,0 @@
-package shared
-
-import (
-	"crypto/rand"
-	"fmt"
-
-	"golang.org/x/crypto/chacha20poly1305"
-)
-
-func EncryptSym(key []byte, plaintext []byte) ([]byte, error) {
-	aead, err := chacha20poly1305.NewX(key)
-	if err != nil {
-		return nil, err
-	}
-
-	nonce := make([]byte, chacha20poly1305.NonceSizeX)
-	if _, err := rand.Read(nonce); err != nil {
-		return nil, err
-	}
-
-	return aead.Seal(nonce, nonce, plaintext, nil), nil
-}
-
-func DecryptSym(key []byte, ciphertext []byte) ([]byte, error) {
-	aead, err := chacha20poly1305.NewX(key)
-	if err != nil {
-		return nil, err
-	}
-
-	if len(ciphertext) < aead.NonceSize() {
-		return nil, fmt.Errorf("ciphertext too short")
-	}
-	nonce, ciphertext := ciphertext[:aead.NonceSize()], ciphertext[aead.NonceSize():]
-
-	return aead.Open(nil, nonce, ciphertext, nil)
-}

shared/proto.go

@@ -6,14 +6,30 @@ const PROTO_VERSION uint16 = 1
 
 const (
 	unused uint16 = iota
-	// - empty -
+	// (client -> server) requests an IP
+	// [ pubkey - 1216 bytes ]
 	REQ_REGISTER
+	// (server -> client) assigns an IP
 	// [ ip - 16 bytes ]
 	RESP_REGISTER
-	// [ encrypted pkt ]
-	REQ_DATA
-	// [ encrypted pkt ]
-	RESP_DATA
+	// (client -> server -> client2) relays an encrypted packet to a specified peer
+	// [ destIP - 16 bytes ] [ srcIP - 16 bytes ] [ encrypted pkt ]
+	ENC_PKT
+	// (client -> server -> *) broadcasts an unsecured packet
+	// [ plaintext pkt ]
+	BROADCAST_PKT
+	// (client -> server) requests peer's pubkey from the server for encapsulation
+	// [ ip - 16 bytes ]
+	REQ_GET_PUBKEY
+	// (server -> client) provides requested pubkey
+	// [ ip - 16 bytes ] [ pubkey - 1216 bytes ]
+	RESP_GET_PUBKEY
+	// (client -> server -> client2) establishes a session key with another peer
+	// [ destIP - 16 bytes ] [ srcIP - 16 bytes ] [ ciphertext - 1120 bytes ]
+	REQ_ESTABLISH
+	// (client2 -> server -> client) acknowledges the session key was established
+	// [ destIP - 16 bytes ] [ srcIP - 16 bytes ]
+	RESP_ESTABLISH
 )
 
 func BuildPkt(pktType uint16, data []byte) []byte {