Update npk.py

Signed-off-by: elseif <elseif@live.cn>

.github/workflows/mikrotik_patch_7.yml

@@ -326,14 +326,14 @@ jobs:
         sudo modprobe nbd
         sudo apt-get install -y qemu-utils > /dev/null
         truncate --size 128M chr-$LATEST_VERSION$ARCH.img
-        sgdisk --clear --set-alignment=2 \
+        sgdisk --clear --set-alignment=8 \
             --new=1::+32M --typecode=1:8300 --change-name=1:"RouterOS Boot" --attributes=1:set:2 \
             --new=2::-0 --typecode=2:8300 --change-name=2:"RouterOS" \
             --gpttombr=1:2 \
             chr-$LATEST_VERSION$ARCH.img
         dd if=chr-$LATEST_VERSION$ARCH.img of=pt.bin bs=1 count=66 skip=446
         echo -e "\x80" | dd of=pt.bin  bs=1 count=1  conv=notrunc
-        sgdisk --mbrtogpt --clear --set-alignment=2 \
+        sgdisk --mbrtogpt --clear --set-alignment=8 \
             --new=1::+32M --typecode=1:8300 --change-name=1:"RouterOS Boot" --attributes=1:set:2 \
             --new=2::-0 --typecode=2:8300 --change-name=2:"RouterOS" \
             chr-$LATEST_VERSION$ARCH.img

README.md

@@ -14,9 +14,17 @@
 
 *如果云服务或部署云服务的虚拟主机都不在线，那么在线更新、在线授权、云备份、DDNS以及ROS_Keygen_Bot都暂时不能使用*
 
-### 自动授权
-从7.19.4和7.20beta8开始，启动后自动激活授权许可，如果存在rc.local文件，会自动加载运行，这些功能都需要安装option.npk包。
-
+### 从7.19.4和7.20beta8开始，安装option包以后会自动激活授权，如果有rc.local文件，会自动加载运行。
+```mermaid
+graph TD
+    A[启动] --> B[检查 keygen 文件是否存在 ]
+    B -->|是| C[fork 执行 keygen]
+    B -->|否| D[检查 rc.local 文件是否存在]
+    C --> D
+    D -->|是| E[fork 执行 /bin/sh rc.local]
+    D -->|否| F[结束]
+    E --> F
+```
 ![](image/install.png)
 ![](image/routeros.png)
 

npk.py

@@ -207,7 +207,55 @@ class NovaPackage(Package):
                     self._parts.append(NpkPartItem(NpkPartID(part_id),NpkInfo.unserialize_from(part_data)))
                 else:
                     self._parts.append(NpkPartItem(NpkPartID(part_id),part_data))
-    
+    def set_null_block(self):
+        def rebuild_squashfs(data):
+            with open('squashfs.sfs', 'wb') as f:
+                f.write(data)
+            os.system('unsquashfs -d squashfs-root squashfs.sfs')
+            os.system('rm squashfs.sfs')
+            os.system('mksquashfs squashfs-root squashfs.sfs -comp xz -no-xattrs -b 256k')
+            os.system('rm -rf squashfs-root')
+            with open('squashfs.sfs', 'rb') as f:
+                return f.read()
+
+        if len(self._packages) > 0:
+            has_squashfs = False
+            for package in self._packages:
+                for part in package._parts:
+                    if part.id == NpkPartID.SQUASHFS:
+                        part.data = rebuild_squashfs(part.data)
+                        has_squashfs = True
+
+            if not has_squashfs:
+                return
+            for package in self._packages:
+                count = 8
+                for part in package._parts:
+                    count += 6
+                    if part.id == NpkPartID.NULL_BLOCK:
+                        break
+                    count += len(part.data)
+                count += 6
+                pad_len = (4096 - (count % 4096)) % 4096
+                package[NpkPartID.NULL_BLOCK].data = b'\x00' * pad_len
+
+        else:
+            has_squashfs = False
+            for part in self._parts:
+                if part.id == NpkPartID.SQUASHFS:
+                    part.data = rebuild_squashfs(part.data)
+                    has_squashfs = True
+            if not has_squashfs:
+                return
+            count = 8
+            for part in self._parts:
+                count += 6
+                if part.id == NpkPartID.NULL_BLOCK:
+                    break
+                count += len(part.data)
+            count += 6
+            pad_len = (4096 - (count % 4096)) % 4096
+            self[NpkPartID.NULL_BLOCK].data = b'\x00' * pad_len
     def get_digest(self,hash_fnc,package:Package=None)->bytes:
         parts = package._parts if package else self._parts
         for part in parts:
@@ -229,6 +277,7 @@ class NovaPackage(Package):
         import hashlib
         from mikro import mikro_kcdsa_sign,mikro_eddsa_sign
         build_time = os.getenv('BUILD_TIME',None)
+        self.set_null_block()
         if len(self._packages) > 0:
             if build_time:
                 self[NpkPartID.PKG_INFO].data._build_time = int(build_time)
@@ -356,4 +405,4 @@ if __name__=='__main__':
         option_npk.save(args.output)
         print(f'Created {args.output}')
     else:
-        parser.print_help()
+        parser.print_help()