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| -rw-r--r-- | unicorn_mode/helper_scripts/ida_context_loader.py | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/unicorn_mode/helper_scripts/ida_context_loader.py b/unicorn_mode/helper_scripts/ida_context_loader.py new file mode 100644 index 00000000..31d47a90 --- /dev/null +++ b/unicorn_mode/helper_scripts/ida_context_loader.py @@ -0,0 +1,197 @@ +# Copyright (c) 2021 Brandon Miller (zznop) +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to +# deal in the Software without restriction, including without limitation the +# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or +# sell copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in +# all copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING +# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS +# IN THE SOFTWARE. + +"""IDA script for loading state that was dumped from a running process using unicorn AFL's GDB +plugin (unicorn_dumper_gdb.py). The dumper script can be found in the AFL++ repository at: +https://github.com/AFLplusplus/AFLplusplus/blob/stable/unicorn_mode/helper_scripts/unicorn_dumper_gdb.py +""" + +import json +from pathlib import Path, PurePath +import zlib +import idaapi +import ida_bytes +import ida_kernwin +import ida_nalt +import ida_segment + + +class ContextLoaderError(Exception): + """Base "catch all" exception for this script + """ + + +class ArchNotSupportedError(ContextLoaderError): + """Exception raised if the input file CPU architecture isn't supported fully + """ + + +def parse_mapping_index(filepath: str): + """Open and unmarshal the _index.json file + + :param filepath: Path to the JSON file + :return: Dict representing index file contents + """ + + if filepath is None: + raise ContextLoaderError('_index.json file was not selected') + + try: + with open(filepath, 'rb') as _file: + return json.load(_file) + except Exception as ex: + raise ContextLoaderError('Failed to parse json file {}'.format(filepath)) from ex + +def get_input_name(): + """Get the name of the input file + + :retrun: Name of the input file + """ + + input_filepath = ida_nalt.get_input_file_path() + return Path(input_filepath).name + +def write_segment_bytes(start: int, filepath: str): + """"Read data from context file and write it to the IDA segment + + :param start: Start address + :param filepath: Path to context file + """ + + with open(filepath, 'rb') as _file: + data = _file.read() + + decompressed_data = zlib.decompress(data) + ida_bytes.put_bytes(start, decompressed_data) + +def create_segment(context_dir: str, segment: dict, is_be: bool): + """Create segment in IDA and map in the data from the file + + :param context_dir: Parent directory of the context files + :param segment: Segment information from _index.json + :param is_be: True if processor is big endian, otherwise False + """ + + input_name = get_input_name() + if Path(segment['name']).name != input_name: + ida_seg = idaapi.segment_t() + ida_seg.start_ea = segment['start'] + ida_seg.end_ea = segment['end'] + ida_seg.bitness = 1 if is_be else 0 + if segment['permissions']['r']: + ida_seg.perm |= ida_segment.SEGPERM_READ + if segment['permissions']['w']: + ida_seg.perm |= ida_segment.SEGPERM_WRITE + if segment['permissions']['x']: + ida_seg.perm |= ida_segment.SEGPERM_EXEC + idaapi.add_segm_ex(ida_seg, Path(segment['name']).name, 'CODE', idaapi.ADDSEG_OR_DIE) + else: + idaapi.add_segm_ex(ida_seg, Path(segment['name']).name, 'DATA', idaapi.ADDSEG_OR_DIE) + + if segment['content_file']: + write_segment_bytes(segment['start'], PurePath(context_dir, segment['content_file'])) + +def create_segments(index: dict, context_dir: str): + """Iterate segments in index JSON, create the segment in IDA, and map in the data from the file + + :param index: _index.json JSON data + :param context_dir: Parent directory of the context files + """ + + info = idaapi.get_inf_structure() + is_be = info.is_be() + for segment in index['segments']: + create_segment(context_dir, segment, is_be) + +def rebase_program(index: dict): + """Rebase the program to the offset specified in the context _index.json + + :param index: _index.json JSON data + """ + + input_name = get_input_name() + new_base = None + for segment in index['segments']: + if not segment['name']: + continue + + segment_name = Path(segment['name']).name + if input_name == segment_name: + new_base = segment['start'] + break + + if not new_base: + raise ContextLoaderError('Input file is not in _index.json') + + current_base = idaapi.get_imagebase() + ida_segment.rebase_program(new_base-current_base, 8) + +def get_pc_by_arch(index: dict) -> int: + """Queries the input file CPU architecture and attempts to lookup the address of the program + counter in the _index.json by register name + + :param index: _index.json JSON data + :return: Program counter value or None + """ + + progctr = None + info = idaapi.get_inf_structure() + if info.procname == 'metapc': + if info.is_64bit(): + progctr = index['regs']['rax'] + elif info.is_32bit(): + progctr = index['regs']['eax'] + return progctr + +def write_reg_info(index: dict): + """Write register info as line comment at instruction pointed to by the program counter and + change focus to that location + + :param index: _index.json JSON data + """ + + cmt = '' + for reg, val in index['regs'].items(): + cmt += f"{reg.ljust(6)} : {hex(val)}\n" + + progctr = get_pc_by_arch(index) + if progctr is None: + raise ArchNotSupportedError( + 'Architecture not fully supported, skipping register status comment') + ida_bytes.set_cmt(progctr, cmt, 0) + ida_kernwin.jumpto(progctr) + +def main(filepath): + """Main - parse _index.json input and map context files into the database + + :param filepath: Path to the _index.json file + """ + + try: + index = parse_mapping_index(filepath) + context_dir = Path(filepath).parent + rebase_program(index) + create_segments(index, context_dir) + write_reg_info(index) + except ContextLoaderError as ex: + print(ex) + +if __name__ == '__main__': + main(ida_kernwin.ask_file(1, '*.json', 'Import file name')) |