Add how to restore genuine firmware (#4)

restore-build.yml

@@ -0,0 +1,30 @@
+name: Build genuine firmware
+on:
+  push:
+    branches: [ 'main' ]
+
+jobs:
+  build-openwrt:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Download encrypted firmware from elecom support
+        run: |
+          curl -O https://dl.elecom.co.jp/support/download/network/wireless_lan/ap/wab-i1750-ps/WAB-I1750-PS-FW-V1-5-10.zip
+          unzip WAB-I1750-PS-FW-V1-5-10.zip
+
+      - name: Remove the first 128 bytes.
+        run: dd if=WAB-I1750-PS-FW-V1-5-10.bin of=WAB-I1750-PS-FW-V1-5-10.bin.enc bs=1 skip=128
+
+      - name: Decrypt binary file
+        run: python3 decrypt.py WAB-I1750-PS-uboot-V1.0.2.bin.enc 8844a2d168b45a2d dec.bin
+
+      - run: file dec.bin
+
+      # - name: Upload build result
+      #   uses: actions/upload-artifact@v4
+      #   with:
+      #     name: restore-genuine-firmware
+      #     path: |
+      #       dec.bin

README.md

@@ -8,8 +8,19 @@ Use at your own risk. I take no responsibility if your device explodes.
 
 <img width="971" alt="" src="https://github.com/macaron/WAB-I1750-PS/assets/19354702/bf99cd71-5b5f-4986-9f78-44377fb2b3d2">
 
+## Restore genuine firmware
+
+- Download latest firmware from elecom support https://www.elecom.co.jp/support/download/network/wireless_lan/ap/wab-i1750-ps/
+- `dd if=WAB-I1750-PS-FW-V1-5-10.bin of=WAB-I1750-PS-FW-V1-5-10.bin.enc bs=1 skip=128`
+- Run decrypt.py
+  - e.g. `python3 decrypt.py WAB-I1750-PS-FW-V1-5-10.bin.enc 8844a2d168b45a2d dec.bin`
+- Upload dec.bin http://192.168.1.1/cgi-bin/luci/admin/system/flash
+- Poweroff
+- Go 192.168.3.1 ID:admin PW:admin, Don't forget change your machine ip address.(In my case, 192.168.3.2/24)
+
 ## Thanks
 
 - https://github.com/openwrt/openwrt
 - https://github.com/masebb/openwrt-WAB-I1750-PS
 - https://github.com/openwrt/openwrt/pull/3661
+- https://github.com/musashino205/openwrt/commit/34d77170457b714e71bcdd33b53e821494bbfd3b

decrypt.py

@@ -0,0 +1,32 @@
+import sys
+
+def xor_decrypt(data, key):
+    key = bytes.fromhex(key)
+    decrypted_data = bytearray()
+
+    for i in range(len(data)):
+        decrypted_data.append(data[i] ^ key[i % len(key)])
+
+    return bytes(decrypted_data)
+
+def main():
+    if len(sys.argv) != 4:
+        print("Usage: python decrypt.py <encrypted_file_path> <key> <decrypted_file_path>")
+        sys.exit(1)
+
+    encrypted_file_path = sys.argv[1]
+    key = sys.argv[2]
+    decrypted_file_path = sys.argv[3]
+
+    with open(encrypted_file_path, "rb") as encrypted_file:
+        encrypted_data = encrypted_file.read()
+
+    decrypted_data = xor_decrypt(encrypted_data, key)
+
+    with open(decrypted_file_path, "wb") as decrypted_file:
+        decrypted_file.write(decrypted_data)
+
+    print("Decrypted!")
+
+if __name__ == "__main__":
+    main()