From 10a7c8f84aae6255d79980aee8aa88b17b3fbf86 Mon Sep 17 00:00:00 2001
From: Willy-JL <49810075+Willy-JL@users.noreply.github.com>
Date: Tue, 25 Apr 2023 17:18:14 +0100
Subject: [PATCH] Backup+restore internal U2F keys on factory reset

---
 .../services/storage/storages/storage_int.c   | 55 +++++++++++++++----
 1 file changed, 45 insertions(+), 10 deletions(-)

diff --git a/applications/services/storage/storages/storage_int.c b/applications/services/storage/storages/storage_int.c
index 2534d47a1..adf016f4e 100644
--- a/applications/services/storage/storages/storage_int.c
+++ b/applications/services/storage/storages/storage_int.c
@@ -193,22 +193,57 @@ static void storage_int_lfs_mount(LFSData* lfs_data, StorageData* storage) {
                        was_fingerprint_outdated;
 
     if(need_format) {
-        // Format storage
-        err = lfs_format(lfs, &lfs_data->config);
+        err = lfs_mount(lfs, &lfs_data->config);
         if(err == 0) {
-            FURI_LOG_I(TAG, "Factory reset: Format successful, trying to mount");
-            furi_hal_rtc_reset_flag(FuriHalRtcFlagFactoryReset);
-            err = lfs_mount(lfs, &lfs_data->config);
+            FURI_LOG_I(TAG, "Factory reset: Mounted for backup");
+
+            // Backup U2F keys
+            lfs_file_t file;
+            lfs_file_open(lfs, &file, ".cnt.u2f", LFS_O_RDWR | LFS_O_CREAT);
+            uint8_t cnt[file.ctz.size];
+            lfs_file_read(lfs, &file, cnt, sizeof(cnt));
+            lfs_file_close(lfs, &file);
+            lfs_file_open(lfs, &file, ".key.u2f", LFS_O_RDWR | LFS_O_CREAT);
+            uint8_t key[file.ctz.size];
+            lfs_file_read(lfs, &file, key, sizeof(key));
+            lfs_file_close(lfs, &file);
+
+            err = lfs_unmount(lfs);
             if(err == 0) {
-                FURI_LOG_I(TAG, "Factory reset: Mounted");
-                storage->status = StorageStatusOK;
+                FURI_LOG_E(TAG, "Factory reset: Unmounted after backup");
+                // Format storage
+                err = lfs_format(lfs, &lfs_data->config);
+                if(err == 0) {
+                    FURI_LOG_I(TAG, "Factory reset: Format successful, trying to mount");
+                    furi_hal_rtc_reset_flag(FuriHalRtcFlagFactoryReset);
+                    err = lfs_mount(lfs, &lfs_data->config);
+                    if(err == 0) {
+                        FURI_LOG_I(TAG, "Factory reset: Mounted");
+
+                        // Restore U2F keys
+                        lfs_file_open(lfs, &file, ".cnt.u2f", LFS_O_RDWR | LFS_O_CREAT);
+                        lfs_file_write(lfs, &file, cnt, sizeof(cnt));
+                        lfs_file_close(lfs, &file);
+                        lfs_file_open(lfs, &file, ".key.u2f", LFS_O_RDWR | LFS_O_CREAT);
+                        lfs_file_write(lfs, &file, key, sizeof(key));
+                        lfs_file_close(lfs, &file);
+
+                        storage->status = StorageStatusOK;
+                    } else {
+                        FURI_LOG_E(TAG, "Factory reset: Mount after format failed");
+                        storage->status = StorageStatusNotMounted;
+                    }
+                } else {
+                    FURI_LOG_E(TAG, "Factory reset: Format failed");
+                    storage->status = StorageStatusNoFS;
+                }
             } else {
-                FURI_LOG_E(TAG, "Factory reset: Mount after format failed");
+                FURI_LOG_E(TAG, "Factory reset: Unmount after backup failed");
                 storage->status = StorageStatusNotMounted;
             }
         } else {
-            FURI_LOG_E(TAG, "Factory reset: Format failed");
-            storage->status = StorageStatusNoFS;
+            FURI_LOG_E(TAG, "Factory reset: Mount for backup failed");
+            storage->status = StorageStatusNotMounted;
         }
     } else {
         // Normal