LyScript自实现汇编搜索功能

通过对LyScript自动化插件进行二次封装,实现从内存中读入目标进程解码后的机器码,并通过Python代码在这些机器码中寻找特定的十六进制字符数组,或直接检索是否存在连续的反汇编指令片段等功能。

  • 插件地址:https://github.com/lyshark/LyScript

搜索内存中的机器码: 内存机器码需要配合LyScript32插件,从内存中寻找指令片段。

from LyScript32 import MyDebug

# 将可执行文件中的单数转换为 0x00 格式
def ReadHexCode(code):
hex_code = []

for index in code:
if index >= 0 and index <= 15:
#print("0" + str(hex(index).replace("0x","")))
hex_code.append("0" + str(hex(index).replace("0x","")))
else:
hex_code.append(hex(index).replace("0x",""))
#print(hex(index).replace("0x",""))

return hex_code

# 获取到内存中的机器码
def GetCode():
try:
ref_code = []
dbg = MyDebug()
connect_flag = dbg.connect()
if connect_flag != 1:
return None

start_address = dbg.get_local_base()
end_address = start_address + dbg.get_local_size()

# 循环得到机器码
for index in range(start_address,end_address):
read_bytes = dbg.read_memory_byte(index)
ref_code.append(read_bytes)

dbg.close()
return ref_code
except Exception:
return False

# 在字节数组中匹配是否与特征码一致
def SearchHexCode(Code,SearchCode,ReadByte):
SearchCount = len(SearchCode)
#print("特征码总长度: {}".format(SearchCount))
for item in range(0,ReadByte):
count = 0
# 对十六进制数切片,每次向后遍历SearchCount
OpCode = Code[ 0+item :SearchCount+item ]
#print("切割数组: {} --> 对比: {}".format(OpCode,SearchCode))
try:
for x in range(0,SearchCount):
if OpCode[x] == SearchCode[x]:
count = count + 1
#print("寻找特征码计数: {} {} {}".format(count,OpCode[x],SearchCode[x]))
if count == SearchCount:
# 如果找到了,就返回True,否则返回False
return True
exit(0)
except Exception:
pass
return False

if __name__ == "__main__":
# 读取到内存机器码
ref_code = GetCode()
if ref_code != False:
# 转为十六进制
hex_code = ReadHexCode(ref_code)
code_size = len(hex_code)

# 指定要搜索的特征码序列
search = ['c0', '74', '0d', '66', '3b', 'c6', '77', '08']

# 搜索特征: hex_code = exe的字节码,search=搜索特征码,code_size = 搜索大小
ret = SearchHexCode(hex_code, search, code_size)
if ret == True:
print("特征码 {} 存在".format(search))
else:
print("特征码 {} 不存在".format(search))
else:
print("读入失败")

输出效果:

搜索内存反汇编代码: 通过LyScript插件读入内存机器码,并在该机器码中寻找指令片段,找到后返回内存首地址。

from LyScript32 import MyDebug

# 检索指定序列中是否存在一段特定的指令集
def SearchOpCode(OpCodeList,SearchCode,ReadByte):
SearchCount = len(SearchCode)
for item in range(0,ReadByte):
count = 0
OpCode_Dic = OpCodeList[ 0 + item : SearchCount + item ]
# print("切割字典: {}".format(OpCode_Dic))
try:
for x in range(0,SearchCount):
if OpCode_Dic[x].get("opcode") == SearchCode[x]:
#print(OpCode_Dic[x].get("addr"),OpCode_Dic[x].get("opcode"))
count = count + 1
if count == SearchCount:
#print(OpCode_Dic[0].get("addr"))
return OpCode_Dic[0].get("addr")
exit(0)
except Exception:
pass

if __name__ == "__main__":
dbg = MyDebug()
connect_flag = dbg.connect()
print("连接状态: {}".format(connect_flag))

# 得到EIP位置
eip = dbg.get_register("eip")

# 反汇编前1000行
disasm_dict = dbg.get_disasm_code(eip,1000)

# 搜索一个指令序列,用于快速查找构建漏洞利用代码
SearchCode = [
["push 0xC0000409", "call 0x003F1B38", "pop ecx"],
["push ecx", "push ebx"]
]

# 检索内存指令集
for item in range(0,len(SearchCode)):
Search = SearchCode[item]
# disasm_dict = 返回汇编指令 Search = 寻找指令集 1000 = 向下检索长度
ret = SearchOpCode(disasm_dict,Search,1000)
if ret != None:
print("指令集: {} --> 首次出现地址: {}".format(SearchCode[item],hex(ret)))

dbg.close()

输出效果: