Merge pull request #3 from ixoworld/fix/ssss-base64-detection

Fix:  base64 backup key detection in BackupManager.decodeRecoveryKey

Author: Michael-Ixo

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@ixo/matrix-bot-sdk",
-  "version": "0.8.0-ixo.5",
+  "version": "0.8.0-ixo.6",
   "description": "TypeScript/JavaScript SDK for Matrix bots and appservices (ixo fork)",
   "repository": {
     "type": "git",

src/e2ee/BackupManager.ts

@@ -125,13 +125,20 @@ export class BackupManager {
      * @returns The recovery key in Base64 format
      */
     public static decodeRecoveryKey(recoveryKey: string): string {
-        // Check if it looks like Base58 (contains spaces or matches Base58 pattern)
-        const hasSpaces = recoveryKey.includes(" ");
-        const looksLikeBase64 = recoveryKey.includes("=") || recoveryKey.includes("+") || recoveryKey.includes("/");
-
-        if (!hasSpaces && looksLikeBase64) {
-            // Already Base64, return as-is
-            return recoveryKey;
+        // Try Base64 first: if it decodes to exactly 32 bytes, it's a raw backup key
+        if (!recoveryKey.includes(" ")) {
+            try {
+                const decoded = Buffer.from(recoveryKey, "base64");
+                if (decoded.length === KEY_SIZE) {
+                    // Verify it's actually base64 and not just coincidence by re-encoding
+                    const reencoded = decoded.toString("base64");
+                    if (reencoded === recoveryKey || reencoded.replace(/=+$/, "") === recoveryKey.replace(/=+$/, "")) {
+                        return recoveryKey;
+                    }
+                }
+            } catch {
+                // Not valid base64, fall through to Base58
+            }
         }
 
         // Decode from Base58