179 lines
6.3 KiB
Python
Executable File
179 lines
6.3 KiB
Python
Executable File
#!/usr/bin/env python
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# Sample code for X86 of Unicorn.
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# Nguyen Anh Quynh <aquynh@gmail.com>
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# KaiJern Lau <kj@theshepherdlab.io>
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from __future__ import print_function
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from unicorn import *
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from unicorn.x86_const import *
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# Original shellcode from this example.
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#X86_CODE32 = b"\xeb\x19\x31\xc0\x31\xdb\x31\xd2\x31\xc9\xb0\x04\xb3\x01\x59\xb2\x05\xcd\x80\x31\xc0\xb0\x01\x31\xdb\xcd\x80\xe8\xe2\xff\xff\xff\x68\x65\x6c\x6c\x6f"
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# Linux/x86 execve /bin/sh shellcode 23 bytes, from http://shell-storm.org/shellcode/files/shellcode-827.php
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# 0: 31 c0 xor eax,eax
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# 2: 50 push eax
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# 3: 68 2f 2f 73 68 push 0x68732f2f
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# 8: 68 2f 62 69 6e push 0x6e69622f
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# d: 89 e3 mov ebx,esp
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# f: 50 push eax
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# 10: 53 push ebx
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# 11: 89 e1 mov ecx,esp
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# 13: b0 0b mov al,0xb
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# 15: cd 80 int 0x80
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X86_CODE32 = b"\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x50\x53\x89\xe1\xb0\x0b\xcd\x80"
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X86_CODE32_SELF = b"\xeb\x1c\x5a\x89\xd6\x8b\x02\x66\x3d\xca\x7d\x75\x06\x66\x05\x03\x03\x89\x02\xfe\xc2\x3d\x41\x41\x41\x41\x75\xe9\xff\xe6\xe8\xdf\xff\xff\xff\x31\xd2\x6a\x0b\x58\x99\x52\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x52\x53\x89\xe1\xca\x7d\x41\x41\x41\x41\x41\x41\x41\x41"
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# Linux/x86 64bit execve /bin/sh shellcode
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# 0: 48 31 ff xor rdi,rdi
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# 3: 57 push rdi
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# 4: 57 push rdi
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# 5: 5e pop rsi
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# 6: 5a pop rdx
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# 7: 48 bf 2f 2f 62 69 6e movabs rdi,0x68732f6e69622f2f
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# e: 2f 73 68
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# 11: 48 c1 ef 08 shr rdi,0x8
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# 15: 57 push rdi
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# 16: 54 push rsp
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# 17: 5f pop rdi
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# 18: 6a 3b push 0x3b
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# 1a: 58 pop rax
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# 1b: 0f 05 syscall
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X86_CODE64 = b"\x48\x31\xff\x57\x57\x5e\x5a\x48\xbf\x2f\x2f\x62\x69\x6e\x2f\x73\x68\x48\xc1\xef\x08\x57\x54\x5f\x6a\x3b\x58\x0f\x05"
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# memory address where emulation starts
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ADDRESS = 0x1000000
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# callback for tracing instructions
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def hook_code(uc, address, size, user_data):
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print(">>> Tracing instruction at 0x%x, instruction size = 0x%x" %(address, size))
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# read this instruction code from memory
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tmp = uc.mem_read(address, size)
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print("*** PC = %x *** :" %(address), end="")
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for i in tmp:
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print(" %02x" %i, end="")
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print("")
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# callback for tracing basic blocks
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def hook_block(uc, address, size, user_data):
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print(">>> Tracing basic block at 0x%x, block size = 0x%x" %(address, size))
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def read_string(uc, address):
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ret = ""
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c = uc.mem_read(address, 1)[0]
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read_bytes = 1
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while c != 0x0:
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ret += chr(c)
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c = uc.mem_read(address + read_bytes, 1)[0]
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read_bytes += 1
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return ret
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# callback for tracing Linux interrupt
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def hook_intr(uc, intno, user_data):
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# only handle Linux syscall
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if intno != 0x80:
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print("got interrupt %x ???" %intno)
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uc.emu_stop()
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return
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eax = uc.reg_read(UC_X86_REG_EAX)
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eip = uc.reg_read(UC_X86_REG_EIP)
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if eax == 1: # sys_exit
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print(">>> 0x%x: interrupt 0x%x, EAX = 0x%x" %(eip, intno, eax))
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uc.emu_stop()
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elif eax == 4: # sys_write
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# ECX = buffer address
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ecx = uc.reg_read(UC_X86_REG_ECX)
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# EDX = buffer size
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edx = uc.reg_read(UC_X86_REG_EDX)
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try:
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buf = uc.mem_read(ecx, edx)
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print(">>> 0x%x: interrupt 0x%x, SYS_WRITE. buffer = 0x%x, size = %u, content = " \
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%(eip, intno, ecx, edx), end="")
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for i in buf:
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print("%c" %i, end="")
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print("")
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except UcError as e:
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print(">>> 0x%x: interrupt 0x%x, SYS_WRITE. buffer = 0x%x, size = %u, content = <unknown>\n" \
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%(eip, intno, ecx, edx))
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elif eax == 11: # sys_write
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ebx = uc.reg_read(UC_X86_REG_EBX)
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filename = read_string(uc, ebx)
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print(">>> SYS_EXECV filename=%s" % filename)
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else:
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print(">>> 0x%x: interrupt 0x%x, EAX = 0x%x" %(eip, intno, eax))
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def hook_syscall32(mu, user_data):
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eax = mu.reg_read(UC_X86_REG_EAX)
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print(">>> got SYSCALL with EAX = 0x%x" %(eax))
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mu.emu_stop()
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def hook_syscall64(mu, user_data):
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rax = mu.reg_read(UC_X86_REG_RAX)
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rdi = mu.reg_read(UC_X86_REG_RDI)
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print(">>> got SYSCALL with RAX = %d" %(rax))
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if rax == 59: #sys_execve
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filename = read_string(mu, rdi)
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print(">>> SYS_EXECV filename=%s" % filename)
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else:
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rip = mu.reg_read(UC_X86_REG_RIP)
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print(">>> Syscall Found at 0x%x: , RAX = 0x%x" %(rip, rax))
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mu.emu_stop()
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# Test X86 32 bit
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def test_i386(mode, code):
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if mode == UC_MODE_32:
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print("Emulate x86_32 code")
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elif mode == UC_MODE_64:
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print("Emulate x86_64 code")
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try:
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# Initialize emulator
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mu = Uc(UC_ARCH_X86, mode)
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# map 2MB memory for this emulation
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mu.mem_map(ADDRESS, 2 * 1024 * 1024)
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# write machine code to be emulated to memory
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mu.mem_write(ADDRESS, code)
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# initialize stack
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mu.reg_write(UC_X86_REG_ESP, ADDRESS + 0x200000)
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# tracing all basic blocks with customized callback
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mu.hook_add(UC_HOOK_BLOCK, hook_block)
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# tracing all instructions with customized callback
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mu.hook_add(UC_HOOK_CODE, hook_code)
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if mode == UC_MODE_32:
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# handle interrupt ourself
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mu.hook_add(UC_HOOK_INTR, hook_intr)
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# handle SYSCALL
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mu.hook_add(UC_HOOK_INSN, hook_syscall32, None, 1, 0, UC_X86_INS_SYSCALL)
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elif mode == UC_MODE_64:
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mu.hook_add(UC_HOOK_INSN, hook_syscall64, None, 1, 0, UC_X86_INS_SYSCALL)
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# emulate machine code in infinite time
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mu.emu_start(ADDRESS, ADDRESS + len(code))
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# now print out some registers
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print(">>> Emulation done")
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except UcError as e:
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print("ERROR: %s" % e)
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if __name__ == '__main__':
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test_i386(UC_MODE_32, X86_CODE32_SELF)
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print("=" * 20)
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test_i386(UC_MODE_32, X86_CODE32)
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print("=" * 20)
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test_i386(UC_MODE_64, X86_CODE64) |