b64_PSK

service/xboard/service.go

@@ -3,8 +3,10 @@ package xboard
 import (
 	"bytes"
 	"context"
+	"crypto/md5"
 	"crypto/rand"
 	"encoding/base64"
+	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -27,17 +29,19 @@ import (
 	"github.com/sagernet/sing/service"
 )
 
-// ss2022UserKey prepares a user key for SS2022:
-// Truncate UUID string to keyLen and encode as Base64 for sing-box.
-func ss2022UserKey(identity string, keyLen int) string {
-	if len(identity) > keyLen {
-		identity = identity[:keyLen]
-	} else if len(identity) < keyLen {
+// ss2022Key derives a secure 2022 key from a seed string (like UUID or ServerKey).
+// Logic: base64(hex(md5(seed)))[:keyLen] -- this is a common panel pattern.
+func ss2022Key(seed string, keyLen int) string {
+	h := md5.Sum([]byte(seed))
+	hexStr := hex.EncodeToString(h[:]) // 32 characters
+	if len(hexStr) > keyLen {
+		hexStr = hexStr[:keyLen]
+	} else if len(hexStr) < keyLen {
 		padded := make([]byte, keyLen)
-		copy(padded, []byte(identity))
-		identity = string(padded)
+		copy(padded, []byte(hexStr))
+		hexStr = string(padded)
 	}
-	return base64.StdEncoding.EncodeToString([]byte(identity))
+	return base64.StdEncoding.EncodeToString([]byte(hexStr))
 }
 
 // ss2022KeyLength returns the required key length for a given SS2022 cipher.
@@ -618,9 +622,11 @@ func (s *Service) setupNode() error {
 		}
 
 		if strings.Contains(method, "2022") {
-			// SS2022: server_key is used DIRECTLY as PSK (like V2bX)
-			ssOptions.Password = serverKey
+			// SS2022 key derivation for panel compatibility
 			keyLen := ss2022KeyLength(method)
+			ssOptions.Password = ss2022Key(serverKey, keyLen)
+
+			// Create a dummy user (will be replaced by syncUsers)
 
 			// Create a dummy user (will be replaced by syncUsers)
 			dummyKey := make([]byte, keyLen)
@@ -892,13 +898,12 @@ func (s *Service) syncUsers() {
 		}
 
 		// V2bX/Xboard approach for SS2022 user key:
-		// Base64 encode the UUID string (clipped/padded to keyLen)
 		if isSS2022 {
 			originalKey := key
-			key = ss2022UserKey(key, ss2022KeyLen)
+			key = ss2022Key(key, ss2022KeyLen)
 			if len(newUsers) == 0 {
 				// Log first user's key derivation for debugging
-				s.logger.Info("SS2022 user key derivation: ID[:", ss2022KeyLen, "]=", originalKey[:min(ss2022KeyLen, len(originalKey))], " → b64_uPSK=", key)
+				s.logger.Info("SS2022 user key derivation: ID[:", ss2022KeyLen, "]=", originalKey, " → b64_PSK=", key)
 			}
 		}