Updated

Author: Nick Miles

esp32_image_parser.py

@@ -1,11 +1,13 @@
 #!/usr/bin/env python
 
 # Convert an ESP 32 OTA partition into an ELF
-
+import sys
+import json
 import os, argparse
 from makeelf.elf import *
 from esptool import *
 from esp32_firmware_reader import *
+from read_nvs import *
 
 def image_base_name(path):
     filename_w_ext = os.path.basename(path)
@@ -209,9 +211,10 @@ def flash_dump_to_elf(filename, partition):
 def main():
     desc = 'ESP32 Firmware Image Parser Utility'
     arg_parser = argparse.ArgumentParser(description=desc)
-    arg_parser.add_argument('action', choices=['show_partitions', 'dump_partition', 'create_elf'], help='Action to take')
+    arg_parser.add_argument('action', choices=['show_partitions', 'dump_partition', 'create_elf', 'dump_nvs'], help='Action to take')
     arg_parser.add_argument('input', help='Firmware image input file')
     arg_parser.add_argument('-output', help='Output file name')
+    arg_parser.add_argument('-nvs_output_type', help='output type for nvs dump', type=str, choices=["text","json"], default="text")
     arg_parser.add_argument('-partition', help='Partition name (e.g. ota_0)')
     arg_parser.add_argument('-v', default=False, help='Verbose output', action='store_true')
 
@@ -226,7 +229,7 @@ def main():
         # parse that ish
         part_table = read_partition_table(fh, verbose)
 
-        if args.action in ['dump_partition', 'create_elf']:
+        if args.action in ['dump_partition', 'create_elf', 'dump_nvs']:
             if (args.partition is None):
                 print("Need partition name")
                 return
@@ -254,8 +257,19 @@ def main():
                             # we have to load from a file
                             output_file = args.output
                             image2elf(dump_file, output_file, verbose)
+                elif args.action == 'dump_nvs':
+                    if part['type'] != 1 or part['subtype'] != 2: # Wifi NVS partition (4 is for encryption key)
+                        print("Uh oh... bad partition type. Can only dump NVS partition type.")
+                    with open(dump_file, 'rb') as fh:
+                        if(args.nvs_output_type != "text"):
+                            sys.stdout = open(os.devnull, 'w') # block print()
+                        pages = read_nvs_pages(fh)
+                        sys.stdout = sys.stdout = sys.__stdout__ # re-enable print()
+                        if(args.nvs_output_type == "json"):
+                            print(json.dumps(pages))
             else:
                 print("Partition '" + part_name + "' not found.")
+                pages = read_nvs_pages(dump_file)
 
 if __name__ == '__main__':
     main()

read_nvs.py

@@ -1,12 +1,8 @@
-import sys
-import json
-import struct
-import sys
 import os
+import struct
 import base64
 import binascii
 from hexdump import hexdump
-import argparse
 
 nvs_types =  {
   0x01: "U8",
@@ -40,7 +36,7 @@
 
 namespaces = {}
 
-def parse_entries(entries, entry_state_bitmap):
+def parse_nvs_entries(entries, entry_state_bitmap):
     entries_out = []
     i = 0
     while i < 126:
@@ -196,7 +192,7 @@ def parse_entries(entries, entry_state_bitmap):
         print("")
     return entries_out
 
-def read_pages(fh):
+def read_nvs_pages(fh):
     pages = []
     fh.seek(0, os.SEEK_END)
     file_len = fh.tell()
@@ -249,7 +245,7 @@ def read_pages(fh):
             entry_data = fh.read(32)
             entries.append(entry_data)
 
-        page_data["entries"] = parse_entries(entries, entry_state_bitmap_decoded)
+        page_data["entries"] = parse_nvs_entries(entries, entry_state_bitmap_decoded)
 
         print("")
         print("")
@@ -260,20 +256,20 @@ def read_pages(fh):
     print("")
     return pages
 
-parser = argparse.ArgumentParser()
-parser.add_argument("nvs_bin_file", help="nvs partition binary file", type=str)
-parser.add_argument("-output_type", help="output type", type=str, choices=["text", "json"], default="text")
+#parser = argparse.ArgumentParser()
+#parser.add_argument("nvs_bin_file", help="nvs partition binary file", type=str)
+#parser.add_argument("-output_type", help="output type", type=str, choices=["text", "json"], default="text")
 
-args = parser.parse_args()
+#args = parser.parse_args()
 
-with open(args.nvs_bin_file, 'rb') as fh:
-  if(args.output_type != "text"):
-    sys.stdout = open(os.devnull, 'w') # block print()
+#with open(args.nvs_bin_file, 'rb') as fh:
+#  if(args.output_type != "text"):
+#    sys.stdout = open(os.devnull, 'w') # block print()
 
-  pages = read_pages(fh)
+#  pages = read_pages(fh)
 
-  sys.stdout = sys.stdout = sys.__stdout__ # re-enable print()
+#  sys.stdout = sys.stdout = sys.__stdout__ # re-enable print()
 
-  if(args.output_type == "json"):
-      print(json.dumps(pages))
+#  if(args.output_type == "json"):
+#      print(json.dumps(pages))