Reverse-skills rev-idapython
IDAPython and IDALib script reference for reverse engineering. Activate when the user needs to write IDAPython scripts in IDA, use IDALib for headless analysis, operate on IDB databases, debug with IDA, manipulate memory/registers, traverse functions/blocks/instructions, work with Hex-Rays decompiler API, handle obfuscation, or batch-process binaries.
git clone https://github.com/P4nda0s/reverse-skills
T=$(mktemp -d) && git clone --depth=1 https://github.com/P4nda0s/reverse-skills "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/rev-idapython" ~/.claude/skills/p4nda0s-reverse-skills-rev-idapython && rm -rf "$T"
skills/rev-idapython/SKILL.mdrev-idapython - IDAPython / IDALib Script Reference
IDAPython script snippets for IDA interactive use and IDALib headless analysis. Use as reference when generating IDAPython code.
- IDAPython: scripts run inside IDA GUI (Script Command, plugin, or IDC console)
- IDALib: headless mode introduced in IDA 9.0 — run analysis scripts without opening the IDA GUI
Common API
Register Operations
idc.get_reg_value('rax') idaapi.set_reg_val("rax", 1234)
Debug Memory Operations
idc.read_dbg_byte(addr) idc.read_dbg_memory(addr, size) idc.read_dbg_dword(addr) idc.read_dbg_qword(addr) idc.patch_dbg_byte(addr, val) idc.add_bpt(0x409437) # add breakpoint idaapi.get_imagebase() # get image base address
Local Memory Operations (modifies IDB database)
idc.get_qword(addr) idc.patch_qword(addr, val) idc.patch_dword(addr, val) idc.patch_word(addr, val) idc.patch_byte(addr, val) idc.get_db_byte(addr) idc.get_bytes(addr, size) idaapi.get_dword(addr) idc.get_strlit_contents # read string literal
Disassembly
GetDisasm(addr) # get disassembly text idc.next_head(ea) # get next instruction address idc.create_insn(addr) # c, Make Code ida_bytes.create_strlit # create string, same as 'A' key ida_funcs.add_func(addr) # p, create function idc.del_items(addr) # U, undefine
Address Conversion
idc.get_name_ea(0, '_sub_6051') # get address by function name
Function Operations
ida_funcs.get_func(ea) # get function descriptor # enumerate all functions for func in idautils.Functions(): print("0x%x, %s" % (func, idc.get_func_name(func)))
Code Snippets
Byte Pattern Search
import ida_bytes import ida_idaapi import ida_funcs import idc # find_bytes_list("90 90 90 90 90") # find_bytes_list("55 ??") # returns list of matching addresses def find_bytes_list(bytes_pattern): ea = -1 result = [] while True: ea = idc.find_bytes(bytes_pattern, ea + 1) if ea == ida_idaapi.BADADDR: break result.append(ea) return result
Appcall - Call Debuggee Functions
# test check_passwd(char *passwd) -> int passwd = ida_idd.Appcall.byref("MyFirstGuess") res = ida_idd.Appcall.check_passwd(passwd) if res.value == 0: print("Good passwd !") else: print("Bad passwd...")
# Explicitly create the buffer as a byref object s_in = Appcall.byref("SomeEncryptedBuffer") # Buffers are always returned byref s_out = Appcall.buffer(" ", SizeOfBuffer) # Call the debuggee Appcall.decrypt_buffer(s_in, s_out, SizeOfBuffer) # Print the result print "decrypted=", s_out.value
loadlib = Appcall.proto("kernel32_LoadLibraryA", "int __stdcall loadlib(const char *fn);") hmod = loadlib("dll_to_inject.dll") getlasterror = Appcall.proto("kernel32_GetLastError", "DWORD __stdcall GetLastError();") print "lasterror=", getlasterror() getcmdline = Appcall.proto("kernel32_GetCommandLineA", "const char *__stdcall getcmdline();") print "command line:", getcmdline()
Cross References
for ref in idautils.XrefsTo(ea): print(hex(ref.frm)) # shorthand [ref.frm for ref in idautils.XrefsTo(start_ea)]
Basic Block Traversal
fn = 0x4800 f_blocks = idaapi.FlowChart(idaapi.get_func(fn), flags=idaapi.FC_PREDS) for block in f_blocks: print(hex(block.start_ea))
# successor blocks for succ in block.succs(): print hex(succ.start_ea) # predecessor blocks for pred in block.preds(): print hex(pred.start_ea)
Debug Memory Read/Write
def patch_dbg_mem(addr, data): for i in range(len(data)): idc.patch_dbg_byte(addr + i, data[i]) def read_dbg_mem(addr, size): dd = [] for i in range(size): dd.append(idc.read_dbg_byte(addr + i)) return bytes(dd)
Read std::string (64-bit)
def dbg_read_cppstr_64(objectAddr): strPtr = idc.read_dbg_qword(objectAddr) result = '' i = 0 while True: onebyte = idc.read_dbg_byte(strPtr + i) if onebyte == 0: break else: result += chr(onebyte) i += 1 return result
Read C String (64-bit)
def dbg_read_cstr_64(objectAddr): strPtr = objectAddr result = '' i = 0 while True: onebyte = idc.read_dbg_byte(strPtr + i) if onebyte == 0: break else: result += chr(onebyte) i += 1 return result
Parse GNU C++ std::map
import idautils import idaapi import idc def parse_gnu_map_header(address): root = idc.read_dbg_qword(address + 0x10) return root def parse_gnu_map_node(address): left = idc.read_dbg_qword(address + 0x10) right = idc.read_dbg_qword(address + 0x18) data = address + 0x20 return left, right, data def parse_gnu_map_travel(address): # address <- std::map struct address result = [] worklist = [parse_gnu_map_header(address)] while len(worklist) > 0: addr = worklist.pop() (left, right, data) = parse_gnu_map_node(addr) if left > 0: worklist.append(left) if right > 0: worklist.append(right); result.append(data) return result # example elements = parse_gnu_map_travel(0x0000557518073EB0) for elem in elements: print(hex(elem))
Read XMM Register (Debug)
def read_xmm_reg(name): rv = idaapi.regval_t() idaapi.get_reg_val(name, rv) return (struct.unpack('Q', rv.bytes())[0])
Step Over and Wait for Debug Event
while ida_dbg.step_over(): wait_for_next_event(WFNE_ANY, -1) rip = idc.get_reg_value("rip") # .....
Iterate Instructions in a Function
for ins in idautils.FuncItems(0x401000): print(hex(ins))
Get Function Callees (Instruction-Based)
def ida_get_callees(func_addr: int) -> list: callees = [] for head in idautils.Heads(func_addr, idaapi.get_func(func_addr).end_ea): if idaapi.is_call_insn(head): callee_ea = idc.get_operand_value(head, 0) callees.append(callee_ea) return callees
Double / Complex Number Memory Operations
def float_to_double_bytearray(value): double_value = ctypes.c_double(value) byte_array = bytearray(ctypes.string_at(ctypes.byref(double_value), ctypes.sizeof(double_value))) return byte_array def set_pos(x, y): # complex<double, double> rbp = idc.get_reg_value("rbp") complex_base = rbp - 0x260 patch_dbg_mem(complex_base, float_to_double_bytearray(x)) patch_dbg_mem(complex_base + 8, float_to_double_bytearray(y)) set_pos(5.0, 6.0)
Import Table
Enumerate Import Table
import ida_nalt nimps = ida_nalt.get_import_module_qty() print("Found %d import(s)..." % nimps) for i in range(nimps): name = ida_nalt.get_import_module_name(i) if not name: print("Failed to get import module name for #%d" % i) name = "<unnamed>" print("Walking imports for module %s" % name) def imp_cb(ea, name, ordinal): if not name: print("%08x: ordinal #%d" % (ea, ordinal)) else: print("%08x: %s (ordinal #%d)" % (ea, name, ordinal)) return True ida_nalt.enum_import_names(i, imp_cb) print("All done...")
Check if Address is an Import Function
def ida_is_import_function(addr: int) -> bool: is_find = False nimps = ida_nalt.get_import_module_qty() for i in range(nimps): def imp_cb(ea, name, ordinal): nonlocal is_find if ea == addr: is_find = True return False return True ida_nalt.enum_import_names(i, imp_cb) return is_find
Enumerate Import Addresses
def ida_enum_import_addr() -> List[int]: import_addrs = [] nimps = ida_nalt.get_import_module_qty() for i in range(nimps): def imp_cb(ea, name, ordinal): nonlocal import_addrs import_addrs.append(ea) return True ida_nalt.enum_import_names(i, imp_cb) return import_addrs
Type Information
Struct Member Traversal
def extract_struct_members(type_name): fields = [] tif = ida_typeinf.tinfo_t() if tif.get_named_type(None, type_name): offset = 0 for iter in tif.iter_struct(): # udm fsize = iter.type.get_size() fields.append({ "offset": iter.offset // 8, # bit offset "size": fsize, "type": iter.type._print() }) offset += fsize else: print(f"Unable to get {type_name} type info.") return fields extract_struct_members("sqlite3_vfs")
Enumerate All Types
til = ida_typeinf.get_idati() for type_name in til.get_type_names(): print(type_name)
List All Struct Types
def list_struct_types(): types = [] til = ida_typeinf.get_idati() for type_name in til.get_type_names(): tif = ida_typeinf.tinfo_t() if tif.get_named_type(None, type_name): if tif.is_struct(): types.append(type_name) return types
Hex-Rays Decompiler API
Decompile a Function
# verified: IDA 9.0 dec = ida_hexrays.decompile(func_addr) # dec is an object, str(dec) converts to text print(str(dec))
Print Microcode at Different Maturity Levels
def print_microcode(func_ea): maturity = ida_hexrays.MMAT_GLBOPT3 # maturity: # MMAT_ZERO, ///< microcode does not exist # MMAT_GENERATED, ///< generated microcode # MMAT_PREOPTIMIZED, ///< preoptimized pass is complete # MMAT_LOCOPT, ///< local optimization of each basic block is complete. # ///< control flow graph is ready too. # MMAT_CALLS, ///< detected call arguments # MMAT_GLBOPT1, ///< performed the first pass of global optimization # MMAT_GLBOPT2, ///< most global optimization passes are done # MMAT_GLBOPT3, ///< completed all global optimization. microcode is fixed now. # MMAT_LVARS, ///< allocated local variables hf = ida_hexrays.hexrays_failure_t() pfn = idaapi.get_func(func_ea) rng = ida_hexrays.mba_ranges_t(pfn) mba = ida_hexrays.gen_microcode(rng, hf, None, ida_hexrays.DECOMP_WARNINGS, maturity) vp = ida_hexrays.vd_printer_t() mba._print(vp) print_microcode(0x1229)
Custom Instruction to User-Defined Call
class udc_exit_t(ida_hexrays.udc_filter_t): def __init__(self, code, name): ida_hexrays.udc_filter_t.__init__(self) if not self.init("int __usercall %s@<R0>(int status@<R1>);" % name): raise Exception("Couldn't initialize udc_exit_t instance") self.code = code self.installed = False def match(self, cdg): return cdg.insn.itype == ida_allins.ARM_svc and cdg.insn.Op1.value == self.code def install(self): ida_hexrays.install_microcode_filter(self, True); self.installed = True def uninstall(self): ida_hexrays.install_microcode_filter(self, False); self.installed = False def toggle_install(self): if self.installed: self.uninstall() else: self.install() udc_exit = udc_exit_t(0x900001, "svc_exit") udc_exit.toggle_install()
Hexrays_Hooks
class MicrocodeCallback(ida_hexrays.Hexrays_Hooks): def __init__(self, *args): super().__init__(*args) def microcode(self, mba: ida_hexrays.mba_t) -> "int": print("microcode generated.") return 0 r = MicrocodeCallback() r.hook()
Obfuscation Helpers
OLLVM - Set Breakpoints on Real Blocks
Set breakpoints on all real block entry addresses. Real blocks are identified by finding predecessors of the OLLVM dispatcher merge point.
Note: identifying real blocks by xrefs to the merge point is a heuristic and may not be fully accurate. Use IDA breakpoint groups for batch management.
fn = 0x401F60 ollvm_tail = 0x405D4B # OLLVM real block merge point f_blocks = idaapi.FlowChart(idaapi.get_func(fn), flags=idaapi.FC_PREDS) for block in f_blocks: for succ in block.succs(): if succ.start_ea == ollvm_tail: print(hex(block.start_ea)) idc.add_bpt(block.start_ea)
Batch Add Breakpoints
def brkall(l): for addr in l: idc.add_bpt(addr)
Firmware Helpers
Search x86 Function Prologues and Create Functions
# verified: IDA 9.0 def make_x86_func(): func_headers = find_bytes_list("55 8B") for h in func_headers: idc.del_items(h) idc.create_insn(h) ida_funcs.add_func(h)
Basic Block Utilities
Get Basic Block Size
# verified: IDA 9.0 def get_bb_size(bbaddr): fn = bbaddr f_blocks = idaapi.FlowChart(idaapi.get_func(fn), flags=idaapi.FC_PREDS) for block in f_blocks: if block.start_ea == bbaddr: return block.end_ea - block.start_ea raise Exception("Not found")
Get Basic Block by Address
def ida_get_bb(ea): f_blocks = idaapi.FlowChart(idaapi.get_func(ea), flags=idaapi.FC_PREDS) for block in f_blocks: if block.start_ea <= ea and ea < block.end_ea: return block return None
Instruction Utilities
Search Next Instruction by Keyword
# verified: IDA 9.0 def search_next_insn(addr, insnkey, max_search=0x100): cnt = 0 while cnt < max_search: addr = idc.next_head(addr) dis = GetDisasm(addr) if insnkey in dis: return addr cnt += 1 return None # example # search_next_insn(addr, 'movdqa')
Undefine a Range (U key equivalent)
# verified: IDA 9.0 def undefine_range(start, end): for i in range(start, end): idc.del_items(i) # example # undefine_range(func_start, func_end)
Search Disassembly Text
# verified: IDA 9.0 def search_text_all(text): import idaapi, idc start_ea = 0 result = [] while True: start_ea = idaapi.find_text(ustr=text, x=0, y=0, sflag=idaapi.SEARCH_DOWN, start_ea=start_ea) if start_ea == idc.BADADDR: break result.append(start_ea) start_ea = idc.next_head(start_ea) return result # example for x in search_text_all('movdqa'): print(GetDisasm(x))
NOP Function
import idaapi import idautils import idc def nop_func(addr_func, arch='arm'): func = ida_funcs.get_func(addr_func) if not func: print("Function not found!") return start = func.start_ea end = func.end_ea print(f"Nopping function at: 0x{start:x} - 0x{end:x}") if arch == 'x86': nop_bytes = [0x90] # x86 NOP elif arch == 'arm': nop_bytes = [0x1F, 0x20, 0x03, 0xD5] # ARM NOP else: print(f"Unsupported architecture: {arch}") return ea = start while ea < end: insn = ida_ua.insn_t() length = ida_ua.decode_insn(insn, ea) if length == 0: print(f"Failed to decode instruction at: 0x{ea:x}") break nop_len = len(nop_bytes) for i in range(0, length, nop_len): for j in range(nop_len): if i + j < length: idc.patch_byte(ea + i + j, nop_bytes[j]) ea += length print("Nopping complete.") # example nop_func(0x401000, 'arm')
IDALib (Headless IDA, IDA 9.0+)
IDALib allows running IDAPython analysis scripts without opening the IDA GUI.
Installation
cd idalib/python pip install . python py-activate-idalib.py
Basic Usage
import idapro # must be the first import import idautils import idc # open idb/binary file ida.open_database("samples/patch.so", True) # enumerate functions for func in idautils.Functions(): func_name = idc.get_func_name(func) print("Function Name: {}, Address: {}".format(func_name, hex(func))) # close and save idb ida.close_database(save=True)
Batch Decompile to JSON
Usage: decompile.py <input_file_elf> <output_file_json>
decompile.py:
import idapro import ida_hexrays import idautils import idc import os import sys import json def _decompile_internal(): result = [] for func in idautils.Functions(): func_name = idc.get_func_name(func) print("Function Name: {}, Address: {}".format(func_name, hex(func))) dec_obj = ida_hexrays.decompile(func) if dec_obj is None: continue dec_str = str(dec_obj) result.append({ 'name': func_name, 'address': hex(func), 'decompiled': dec_str }) return result def decomple_export(file, out_file): ida.open_database(file, True) r = _decompile_internal() ida.close_database(save=False) open(out_file, "w").write(json.dumps(r, indent=4)) if __name__ == "__main__": if len(sys.argv) != 3: print("Usage: {} <input_file_elf> <output_file_json>".format(sys.argv[0])) sys.exit(1) decomple_export(sys.argv[1], sys.argv[2])
Multiprocess Batch Decompile
import os import time from multiprocessing import Pool args = { "NUM_WORKERS": 8, "INPUT_DIR": "/Users/ctf/idek2024/baby2/baby", "OUTPUT_DIR": "/Users/ctf/idek2024/baby2/decompiled", "NUM_MAX_RETRY": 3 } def decomple_one(file, out_file): retry = 0 while True: os.system("python3 decompile.py {} {}".format(file, out_file)) if os.path.exists(out_file): break retry += 1 if retry >= args["NUM_MAX_RETRY"]: return "Failed to decompile {}".format(file) time.sleep(1) return None if __name__ == "__main__": if not os.path.exists(args["OUTPUT_DIR"]): os.makedirs(args["OUTPUT_DIR"]) files = os.listdir(args["INPUT_DIR"]) files = [os.path.join(args["INPUT_DIR"], f) for f in files] out_files = [os.path.join(args["OUTPUT_DIR"], os.path.basename(f) + ".json" ) for f in files] with Pool(args["NUM_WORKERS"]) as p: r = p.starmap(decomple_one, zip(files, out_files)) for i in r: if i is not None: print(i)