Catching errors more gracefully when downloading apks (closes: #158)

mvt/android/cli.py

@@ -5,7 +5,6 @@
 
 import logging
 import os
-import sys
 
 import click
 from rich.logging import RichHandler
@@ -51,17 +50,23 @@ def cli():
               help="Specify a path to a folder where you want to store the APKs")
 @click.option("--from-file", "-f", type=click.Path(exists=True),
               help="Instead of acquiring from phone, load an existing packages.json file for lookups (mainly for debug purposes)")
-def download_apks(all_apks, virustotal, koodous, all_checks, output, from_file, serial):
+@click.pass_context
+def download_apks(ctx, all_apks, virustotal, koodous, all_checks, output, from_file, serial):
     try:
         if from_file:
             download = DownloadAPKs.from_json(from_file)
         else:
-            if output and not os.path.exists(output):
+            # TODO: Do we actually want to be able to run without storing any file?
+            if not output:
+                log.critical("You need to specify an output folder with --output!")
+                ctx.exit(1)
+
+            if not os.path.exists(output):
                 try:
                     os.makedirs(output)
                 except Exception as e:
                     log.critical("Unable to create output folder %s: %s", output, e)
-                    sys.exit(-1)
+                    ctx.exit(1)
 
             download = DownloadAPKs(output_folder=output, all_apks=all_apks)
             if serial:
@@ -80,7 +85,7 @@ def download_apks(all_apks, virustotal, koodous, all_checks, output, from_file,
             koodous_lookup(packages)
     except KeyboardInterrupt:
         print("")
-        sys.exit(-1)
+        ctx.exit(1)
 
 
 #==============================================================================
@@ -93,7 +98,8 @@ def download_apks(all_apks, virustotal, koodous, all_checks, output, from_file,
               help="Specify a path to a folder where you want to store JSON results")
 @click.option("--list-modules", "-l", is_flag=True, help="Print list of available modules and exit")
 @click.option("--module", "-m", help="Name of a single module you would like to run instead of all")
-def check_adb(iocs, output, list_modules, module, serial):
+@click.pass_context
+def check_adb(ctx, iocs, output, list_modules, module, serial):
     if list_modules:
         log.info("Following is the list of available check-adb modules:")
         for adb_module in ADB_MODULES:
@@ -108,7 +114,7 @@ def check_adb(iocs, output, list_modules, module, serial):
             os.makedirs(output)
         except Exception as e:
             log.critical("Unable to create output folder %s: %s", output, e)
-            sys.exit(-1)
+            ctx.exit(1)
 
     if iocs:
         # Pre-load indicators for performance reasons.
@@ -147,7 +153,8 @@ def check_adb(iocs, output, list_modules, module, serial):
 @click.option("--iocs", "-i", type=click.Path(exists=True), help="Path to indicators file")
 @click.option("--output", "-o", type=click.Path(exists=False), help=OUTPUT_HELP_MESSAGE)
 @click.argument("BACKUP_PATH", type=click.Path(exists=True))
-def check_backup(iocs, output, backup_path, serial):
+@click.pass_context
+def check_backup(ctx, iocs, output, backup_path, serial):
     log.info("Checking ADB backup located at: %s", backup_path)
 
     if output and not os.path.exists(output):
@@ -155,7 +162,7 @@ def check_backup(iocs, output, backup_path, serial):
             os.makedirs(output)
         except Exception as e:
             log.critical("Unable to create output folder %s: %s", output, e)
-            sys.exit(-1)
+            ctx.exit(1)
 
     if iocs:
         # Pre-load indicators for performance reasons.
@@ -168,7 +175,7 @@ def check_backup(iocs, output, backup_path, serial):
         if os.path.basename(backup_path) == "backup.ab":
             log.info("You can use ABE (https://github.com/nelenkov/android-backup-extractor) " \
                      "to extract 'backup.ab' files!")
-        sys.exit(-1)
+        ctx.exit(1)
 
     for module in BACKUP_MODULES:
         m = module(base_folder=backup_path, output_folder=output,

mvt/android/download_apks.py

@@ -10,6 +10,7 @@ import os
 import pkg_resources
 from tqdm import tqdm
 
+from mvt.common.module import InsufficientPrivileges
 from mvt.common.utils import get_sha256_from_file_path
 
 from .modules.adb.base import AndroidExtraction
@@ -139,6 +140,11 @@ class DownloadAPKs(AndroidExtraction):
                               miniters=1) as pp:
                 self._adb_download(remote_path, local_path,
                                    progress_callback=pp.update_to)
+        except InsufficientPrivileges:
+            log.warn("Unable to pull package file from %s: insufficient privileges, it might be a system app",
+                     remote_path)
+            self._adb_reconnect()
+            return None
         except Exception as e:
             log.exception("Failed to pull package file from %s: %s",
                           remote_path, e)

mvt/android/modules/adb/base.py

@@ -15,6 +15,7 @@ from adb_shell.adb_device import AdbDeviceTcp, AdbDeviceUsb
 from adb_shell.auth.keygen import keygen, write_public_keyfile
 from adb_shell.auth.sign_pythonrsa import PythonRSASigner
 from adb_shell.exceptions import AdbCommandFailureException, DeviceAuthError
+from adb_shell.exceptions import UsbReadFailedError
 from usb1 import USBErrorAccess, USBErrorBusy
 
 from mvt.common.module import InsufficientPrivileges, MVTModule
@@ -77,8 +78,8 @@ class AndroidExtraction(MVTModule):
             except DeviceAuthError:
                 log.error("You need to authorize this computer on the Android device. Retrying in 5 seconds...")
                 time.sleep(5)
-            except Exception as e:
-                log.critical(e)
+            except UsbReadFailedError:
+                log.error("Unable to connect to the device over USB. Try to unplug, plug the device and start again.")
                 sys.exit(-1)
             else:
                 break