IDA python脚本一键生成libhasp_android_x补丁文件加载自己的so

主要是对某safe加密锁的android保护库的补丁工具，最开始是手动修改代码，极不方便。有了这个脚本工具可一键生成补丁，轻松自在。
先用IDA加载libhasp_android_x.so大概分析一下，下面是导出函数表

import logging
from elftools.elf.elffile import ELFFile

#需要手动修改的仅2处
#dlopen函数地址
plt_dlopen_of = 0x00007264
plt_dlopen_of = 0x00005B70  #老

#hasp_login_scope中找个空调函数，IDA辅助找合适位置
hasp_login_scope_BL = 0xA6B0

#固定或可以自动定位的
FileOrg = "libhasp_android_xxxx.so"
#新生成的文件
FileNew = FileOrg + ".new"
#hasp_update偏移,可以自动定位
hasp_update_of = 0x00000000
# 字符串所在偏移
FileNameAdd = 0x00000000

#字节码补丁可实现调用id_xxx1.so
hasp_update_code_new = b'\x00\x48\x2D\xE9\x0D\xB0\xA0\xE1\x0C\x00\x9F\xE5\x00\x00\x8F\xE0\x01\x10\x00\xE3\x1C\x00\x00\xEB\x00\x88\xBD\xE8\xEA\xFC\xFF\xFF'

# 配置日志记录
logging.basicConfig(
    filename='AutoFixSo.log',  # 指定日志文件名
    filemode='w',            # 写入模式，'w'表示覆盖写入，'a'表示追加写入
    format='%(asctime)s - %(levelname)s - %(message)s',  # 日志格式
    datefmt='%Y-%m-%d %H:%M:%S',  # 日期格式
    level=logging.DEBUG      # 日志级别
)

def find_string_offset(binary_file, search_string):
    with open(binary_file, 'rb') as f:
        data = f.read()
        index = data.find(search_string.encode())
        if index != -1:
            print(f"Found '{search_string}' at offset 0x{index:X}")
            return index
        else:
            print(f"String '{search_string}' not found in the binary file.")
            return -1

#文件名libhasp_android_xxx1.so的偏移地址
FileNameAdd = find_string_offset(FileOrg,FileOrg)
 

def list_exported_functions(elf_file_path,fun_name):
    with open(elf_file_path, 'rb') as file:
        elf = ELFFile(file)
        symtab = elf.get_section_by_name('.dynsym')
        if not symtab:
            print("No dynamic symbol table found.")
            return 0

        for symbol in symtab.iter_symbols():
            if symbol['st_info']['type'] == 'STT_FUNC':
                #print(symbol.name)
                if symbol.name == fun_name:
                    print(f"Function: {symbol.name}, Address: 0x{symbol['st_value']:X}")
                    return symbol['st_value']
                
#取ELF中目标函数的偏移地址
hasp_update_of = list_exported_functions(FileOrg,"hasp_update")
logging.info(f"hasp_update_of = 0x{hasp_update_of:x}")
logging.info(f"plt_dlopen_of = 0x{plt_dlopen_of:x}")
logging.info(f"hasp_login_scope_nullsub = 0x{hasp_login_scope_BL:x}")
logging.info(f"FileNameAdd = 0x{FileNameAdd:x}")
    
def modify_high_byte(dword, new_byte):
    # 清除高第一个字节
    dword &= 0x00FFFFFF
    # 设置新的高第一个字节
    dword |= (new_byte << 24)
    return dword   

# 打开二进制文件
with open(FileOrg, 'rb') as f:
    data = f.read()

# 打开文件以写入模式
with open(FileNew, 'wb') as f:
    # 将数据写回文件
    f.write(data)
    # 移动到需要修改的位置hasp_update
    f.seek(hasp_update_of)
    # 写入新的二进制数据
    f.write(hasp_update_code_new)
    print(f"patch hasp_update done")
    
    #修正 BL dlopen
    BL_dlopen_of = hasp_update_of + 0x14
    print(f"patch BL dlopen @ 0x{BL_dlopen_of:X}")
    f.seek(BL_dlopen_of)
    #计算跳转
    dwTmp = plt_dlopen_of - (BL_dlopen_of + 8)
    dwTmp2 = int(dwTmp/4)
    print(f"dwTmp2 {hex(dwTmp2 & 0xffffffff)}")
    newByte = 0xeb
    newDWORD = modify_high_byte(dwTmp2,newByte) 
    newCode = newDWORD.to_bytes(4,byteorder='little')
    f.write(newCode)

    #修正字符串 7dc0 - 7DA4 = 1c
    newStrof = FileNameAdd - BL_dlopen_of + 0x0d
    newStrof = newStrof & 0xFFFFFFFF
    f.seek(hasp_update_of + 0x1c)
    newCode = newStrof.to_bytes(4,byteorder='little')
    f.write(newCode)

    #计算跳转 (0x00007DA4 - (0x0000BF34+8))/4 = FFFFEF9A
    dwTmp = hasp_login_scope_BL + 8
    dwNew2 = int((hasp_update_of - dwTmp)/4)
    print(f"DWORD {hex(dwNew2 & 0xffffffff)}")
    
    newByte = 0xeb
    hasp_login_scope_BL_CODE = modify_high_byte(dwNew2,newByte) 
    print(f"hasp_login_scope_BL_CODE {hex(hasp_login_scope_BL_CODE & 0xffffffff)}")
    #修改hasp_login_scope中的空调函数，跳到hasp_update      
    f.seek(hasp_login_scope_BL)
    bData = hasp_login_scope_BL_CODE.to_bytes(4,byteorder='little')
    f.write(bData)
    f.close()