Setup stack properly for calls, fixes AeonLucid#29.

androidemu/emulator.py

@@ -124,7 +124,7 @@ def call_symbol(self, module, symbol_name, *argv):
             logger.error('Unable to find symbol \'%s\' in module \'%s\'.' % (symbol_name, module.filename))
             return
 
-        self.call_native(symbol.address, *argv)
+        return self.call_native(symbol.address, *argv)
 
     def call_native(self, addr, *argv):
         # Detect JNI call

androidemu/java/helpers/native_method.py

@@ -30,12 +30,14 @@ def native_write_args(emu, *argv):
     if amount >= 5:
         sp_start = emu.mu.reg_read(UC_ARM_REG_SP)
         sp_current = sp_start - STACK_OFFSET  # Need to offset because our hook pushes one register on the stack.
+        sp_current = sp_current - (4 * (amount - 4))  # Reserve space for arguments.
+        sp_end = sp_current
 
         for arg in argv[4:]:
-            emu.mu.mem_write(sp_current - STACK_OFFSET, native_translate_arg(emu, arg).to_bytes(4, byteorder='little'))
-            sp_current = sp_current - 4
+            emu.mu.mem_write(sp_current, native_translate_arg(emu, arg).to_bytes(4, byteorder='little'))
+            sp_current = sp_current + 4
 
-        emu.mu.reg_write(UC_ARM_REG_SP, sp_current)
+        emu.mu.reg_write(UC_ARM_REG_SP, sp_end)
 
 
 def native_read_args(mu, args_count):

androidemu/java/jni_env.py

@@ -1411,6 +1411,7 @@ def get_string_utf_chars(self, mu, env, string, is_copy_ptr):
 
     @native_method
     def release_string_utf_chars(self, mu, env, string, utf_ptr):
+        logger.debug("JNIEnv->ReleaseStringUTFChars(%x, %x) was called" % (string, utf_ptr))
         pass
 
     @native_method

tests/test_native.py

@@ -1,9 +1,9 @@
 import logging
-import posixpath
+import os
 import sys
 import unittest
 
-from unicorn import UC_HOOK_MEM_UNMAPPED, UC_HOOK_CODE
+from unicorn import *
 
 from androidemu.emulator import Emulator
 from samples import debug_utils
@@ -14,27 +14,39 @@
     format="%(asctime)s %(levelname)7s %(name)34s | %(message)s"
 )
 
-dir_samples = posixpath.join(posixpath.dirname(__file__), "..", "samples")
+dir_samples = os.path.join(os.path.dirname(__file__), "..", "samples")
 
 
 class TestNative(unittest.TestCase):
 
-    def test_something(self):
+    def testOneArg(self):
         # Initialize emulator
         emulator = Emulator(
             vfp_inst_set=True,
-            vfs_root=posixpath.join(dir_samples, "vfs")
+            vfs_root=os.path.join(dir_samples, "vfs")
         )
 
-        emulator.load_library(posixpath.join(dir_samples, "example_binaries", "libdl.so"), do_init=False)
-        emulator.load_library(posixpath.join(dir_samples, "example_binaries", "libc.so"), do_init=False)
-        emulator.load_library(posixpath.join(dir_samples, "example_binaries", "libstdc++.so"), do_init=False)
-        module = emulator.load_library(posixpath.join(posixpath.dirname(__file__), "test_binaries", "test_native.so"), do_init=False)
+        emulator.load_library(os.path.join(dir_samples, "example_binaries", "libdl.so"))
+        emulator.load_library(os.path.join(dir_samples, "example_binaries", "libc.so"))
+        emulator.load_library(os.path.join(dir_samples, "example_binaries", "libstdc++.so"))
+        module = emulator.load_library(os.path.join(os.path.dirname(__file__), "test_binaries", "test_native.so"))
 
-        print(module.base)
+        res = emulator.call_symbol(module, 'Java_com_aeonlucid_nativetesting_MainActivity_testOneArg', emulator.java_vm.jni_env.address_ptr, 0x00, 'Hello')
 
-        emulator.mu.hook_add(UC_HOOK_CODE, debug_utils.hook_code)
-        emulator.mu.hook_add(UC_HOOK_MEM_UNMAPPED, debug_utils.hook_unmapped)
-        res = emulator.call_symbol(module, 'Java_com_aeonlucid_nativetesting_MainActivity_testOneArg', emulator.java_vm.address_ptr, 0x00, 'Hello', 'asd')
+        self.assertEqual('Hello', res)
 
-        print(res)
+    def testSixArg(self):
+        # Initialize emulator
+        emulator = Emulator(
+            vfp_inst_set=True,
+            vfs_root=os.path.join(dir_samples, "vfs")
+        )
+
+        emulator.load_library(os.path.join(dir_samples, "example_binaries", "libdl.so"))
+        emulator.load_library(os.path.join(dir_samples, "example_binaries", "libc.so"))
+        emulator.load_library(os.path.join(dir_samples, "example_binaries", "libstdc++.so"))
+        module = emulator.load_library(os.path.join(os.path.dirname(__file__), "test_binaries", "test_native.so"))
+
+        res = emulator.call_symbol(module, 'Java_com_aeonlucid_nativetesting_MainActivity_testSixArg', emulator.java_vm.jni_env.address_ptr, 0x00, 'One', 'Two', 'Three', 'Four', 'Five', 'Six')
+
+        self.assertEqual('OneTwoThreeFourFiveSix', res)