#-*- coding:utf-8 -*- import re import codecs from builtins import range from miasm.core.utils import force_str from miasm.expression.expression import ExprId, ExprInt, ExprOp, LocKey import miasm.core.asmblock as asmblock from miasm.core.cpu import instruction, base_expr from miasm.core.asm_ast import AstInt, AstId, AstOp declarator = {'byte': 8, 'word': 16, 'dword': 32, 'qword': 64, 'long': 32, } size2pck = {8: 'B', 16: 'H', 32: 'I', 64: 'Q', } EMPTY_RE = re.compile(r'\s*$') COMMENT_RE = re.compile(r'\s*;\S*') LOCAL_LABEL_RE = re.compile(r'\s*(\.L\S+)\s*:') DIRECTIVE_START_RE = re.compile(r'\s*\.') DIRECTIVE_RE = re.compile(r'\s*\.(\S+)') LABEL_RE = re.compile(r'\s*(\S+)\s*:') FORGET_LABEL_RE = re.compile(r'\s*\.LF[BE]\d\s*:') class Directive(object): """Stand for Directive""" pass class DirectiveAlign(Directive): """Stand for alignment representation""" def __init__(self, alignment=1): self.alignment = alignment def __str__(self): return "Alignment %s" % self.alignment class DirectiveSplit(Directive): """Stand for alignment representation""" pass class DirectiveDontSplit(Directive): """Stand for alignment representation""" pass STATE_NO_BLOC = 0 STATE_IN_BLOC = 1 def asm_ast_to_expr_with_size(arg, loc_db, size): if isinstance(arg, AstId): return ExprId(force_str(arg.name), size) if isinstance(arg, AstOp): args = [asm_ast_to_expr_with_size(tmp, loc_db, size) for tmp in arg.args] return ExprOp(arg.op, *args) if isinstance(arg, AstInt): return ExprInt(arg.value, size) return None def parse_txt(mnemo, attrib, txt, loc_db): """Parse an assembly listing. Returns an AsmCfg instance @mnemo: architecture used @attrib: architecture attribute @txt: assembly listing @loc_db: the LocationDB instance used to handle labels of the listing """ C_NEXT = asmblock.AsmConstraint.c_next C_TO = asmblock.AsmConstraint.c_to lines = [] # parse each line for line in txt.split('\n'): # empty if EMPTY_RE.match(line): continue # comment if COMMENT_RE.match(line): continue # labels to forget if FORGET_LABEL_RE.match(line): continue # label beginning with .L match_re = LABEL_RE.match(line) if match_re: label_name = match_re.group(1) label = loc_db.get_or_create_name_location(label_name) lines.append(label) continue # directive if DIRECTIVE_START_RE.match(line): match_re = DIRECTIVE_RE.match(line) directive = match_re.group(1) if directive in ['text', 'data', 'bss']: continue if directive in ['string', 'ascii']: # XXX HACK line = line.replace(r'\n', '\n').replace(r'\r', '\r') raw = line[line.find(r'"') + 1:line.rfind(r'"')] raw = codecs.escape_decode(raw)[0] if directive == 'string': raw += b"\x00" lines.append(asmblock.AsmRaw(raw)) continue if directive == 'ustring': # XXX HACK line = line.replace(r'\n', '\n').replace(r'\r', '\r') raw = line[line.find(r'"') + 1:line.rfind(r'"')] + "\x00" raw = codecs.escape_decode(raw)[0] out = b'' for i in range(len(raw)): out += raw[i:i+1] + b'\x00' lines.append(asmblock.AsmRaw(out)) continue if directive in declarator: data_raw = line[match_re.end():].split(' ', 1)[1] data_raw = data_raw.split(',') size = declarator[directive] expr_list = [] # parser for element in data_raw: element = element.strip() element_parsed = base_expr.parseString(element)[0] element_expr = asm_ast_to_expr_with_size(element_parsed, loc_db, size) expr_list.append(element_expr) raw_data = asmblock.AsmRaw(expr_list) raw_data.element_size = size lines.append(raw_data) continue if directive == 'comm': # TODO continue if directive == 'split': # custom command lines.append(DirectiveSplit()) continue if directive == 'dontsplit': # custom command lines.append(DirectiveDontSplit()) continue if directive == "align": align_value = int(line[match_re.end():], 0) lines.append(DirectiveAlign(align_value)) continue if directive in ['file', 'intel_syntax', 'globl', 'local', 'type', 'size', 'align', 'ident', 'section']: continue if directive[0:4] == 'cfi_': continue raise ValueError("unknown directive %s" % directive) # label match_re = LABEL_RE.match(line) if match_re: label_name = match_re.group(1) label = loc_db.get_or_create_name_location(label_name) lines.append(label) continue # code if ';' in line: line = line[:line.find(';')] line = line.strip(' ').strip('\t') instr = mnemo.fromstring(line, loc_db, attrib) lines.append(instr) asmblock.log_asmblock.info("___pre asm oki___") # make asmcfg cur_block = None state = STATE_NO_BLOC i = 0 asmcfg = asmblock.AsmCFG(loc_db) block_to_nlink = None delayslot = 0 while i < len(lines): if delayslot: delayslot -= 1 if delayslot == 0: state = STATE_NO_BLOC line = lines[i] # no current block if state == STATE_NO_BLOC: if isinstance(line, DirectiveDontSplit): block_to_nlink = cur_block i += 1 continue elif isinstance(line, DirectiveSplit): block_to_nlink = None i += 1 continue elif not isinstance(line, LocKey): # First line must be a label. If it's not the case, generate # it. loc = loc_db.add_location() cur_block = asmblock.AsmBlock(loc_db, loc, alignment=mnemo.alignment) else: cur_block = asmblock.AsmBlock(loc_db, line, alignment=mnemo.alignment) i += 1 # Generate the current block asmcfg.add_block(cur_block) state = STATE_IN_BLOC if block_to_nlink: block_to_nlink.addto( asmblock.AsmConstraint( cur_block.loc_key, C_NEXT ) ) block_to_nlink = None continue # in block elif state == STATE_IN_BLOC: if isinstance(line, DirectiveSplit): state = STATE_NO_BLOC block_to_nlink = None elif isinstance(line, DirectiveDontSplit): state = STATE_NO_BLOC block_to_nlink = cur_block elif isinstance(line, DirectiveAlign): cur_block.alignment = line.alignment elif isinstance(line, asmblock.AsmRaw): cur_block.addline(line) block_to_nlink = cur_block elif isinstance(line, LocKey): if block_to_nlink: cur_block.addto( asmblock.AsmConstraint(line, C_NEXT) ) block_to_nlink = None state = STATE_NO_BLOC continue # instruction elif isinstance(line, instruction): cur_block.addline(line) block_to_nlink = cur_block if not line.breakflow(): i += 1 continue if delayslot: raise RuntimeError("Cannot have breakflow in delayslot") if line.dstflow(): for dst in line.getdstflow(loc_db): if not isinstance(dst, ExprId): continue if dst in mnemo.regs.all_regs_ids: continue cur_block.addto(asmblock.AsmConstraint(dst.name, C_TO)) if not line.splitflow(): block_to_nlink = None delayslot = line.delayslot + 1 else: raise RuntimeError("unknown class %s" % line.__class__) i += 1 for block in asmcfg.blocks: # Fix multiple constraints block.fix_constraints() # Log block asmblock.log_asmblock.info(block) return asmcfg