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#!/usr/bin/env python
#-*- coding:utf-8 -*-
import re
import miasm2.expression.expression as m2_expr
import miasm2.core.asmbloc as asmbloc
from miasm2.core.cpu import gen_base_expr, parse_ast
declarator = {'byte': 8,
'word': 16,
'dword': 32,
'qword': 64,
'long': 32,
}
size2pck = {8: 'B',
16: 'H',
32: 'I',
64: 'Q',
}
def guess_next_new_label(symbol_pool, gen_label_index=0):
i = 0
gen_name = "loc_%.8X"
while True:
name = gen_name % i
l = symbol_pool.getby_name(name)
if l is None:
return symbol_pool.add_label(name)
i += 1
def replace_expr_labels(e, symbol_pool, replace_id):
if not isinstance(e, m2_expr.ExprId):
return e
if not isinstance(e.name, asmbloc.asm_label):
return e
old_lbl = e.name
new_lbl = symbol_pool.getby_name_create(old_lbl.name)
replace_id[e] = m2_expr.ExprId(new_lbl, e.size)
return m2_expr.ExprId(new_lbl, e.size)
def replace_orphan_labels(instr, symbol_pool):
for i, arg in enumerate(instr.args):
replace_id = {}
arg.visit(lambda e:replace_expr_labels(e,
symbol_pool,
replace_id))
instr.args[i] = instr.args[i].replace_expr(replace_id)
def parse_txt(mnemo, attrib, txt, symbol_pool=None, gen_label_index=0):
if symbol_pool is None:
symbol_pool = asmbloc.asm_symbol_pool()
lines_text = []
lines_data = []
lines_bss = []
C_NEXT = asmbloc.asm_constraint.c_next
C_TO = asmbloc.asm_constraint.c_to
lines = lines_text
# parse each line
for line in txt.split('\n'):
# empty
if re.match(r'\s*$', line):
continue
# comment
if re.match(r'\s*;\S*', line):
continue
# labels to forget
r = re.match(r'\s*\.LF[BE]\d\s*:', line)
if r:
continue
# label beginning with .L
r = re.match(r'\s*(\.L\S+)\s*:', line)
if r:
l = r.groups()[0]
l = symbol_pool.getby_name_create(l)
lines.append(l)
continue
# directive
if re.match(r'\s*\.', line):
r = re.match(r'\s*\.(\S+)', line)
directive = r.groups()[0]
if directive == 'text':
lines = lines_text
continue
if directive == 'data':
lines = lines_data
continue
if directive == 'bss':
lines = lines_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 = raw.decode('string_escape')
if directive == 'string':
raw += "\x00"
lines.append(asmbloc.asm_raw(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 = raw.decode('string_escape')
raw = "".join([string + '\x00' for string in raw])
lines.append(asmbloc.asm_raw(raw))
continue
if directive in declarator:
data_raw = line[r.end():].split(' ', 1)[1]
data_raw = data_raw.split(',')
size = declarator[directive]
data_int = []
# parser
base_expr = gen_base_expr()[2]
my_var_parser = parse_ast(lambda x: m2_expr.ExprId(x, size),
lambda x:
m2_expr.ExprInt_fromsize(size, x))
base_expr.setParseAction(my_var_parser)
for b in data_raw:
b = b.strip()
x = base_expr.parseString(b)[0]
data_int.append(x.canonize())
raw = data_int
x = asmbloc.asm_raw(raw)
x.element_size = size
lines.append(x)
continue
if directive == 'comm':
# TODO
continue
if directive == 'split': # custom command
x = asmbloc.asm_raw()
x.split = True
lines.append(x)
continue
if directive == 'dontsplit': # custom command
lines.append(asmbloc.asm_raw())
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" % str(directive))
# label
r = re.match(r'\s*(\S+)\s*:', line)
if r:
l = r.groups()[0]
l = symbol_pool.getby_name_create(l)
lines.append(l)
continue
# code
if ';' in line:
line = line[:line.find(';')]
line = line.strip(' ').strip('\t')
instr = mnemo.fromstring(line, attrib)
# replace orphan asm_label with labels from symbol_pool
replace_orphan_labels(instr, symbol_pool)
if instr.dstflow():
instr.dstflow2label(symbol_pool)
lines.append(instr)
asmbloc.log_asmbloc.info("___pre asm oki___")
# make blocs
blocs_sections = []
bloc_num = 0
b = None
for lines in [lines_text, lines_data, lines_bss]:
state = 0
i = 0
blocs = []
blocs_sections.append(blocs)
bloc_to_nlink = None
block_may_link = False
while i < len(lines):
# no current bloc
if state == 0:
if not isinstance(lines[i], asmbloc.asm_label):
l = guess_next_new_label(symbol_pool)
lines[i:i] = [l]
else:
l = lines[i]
b = asmbloc.asm_bloc(l)
b.bloc_num = bloc_num
bloc_num += 1
blocs.append(b)
state = 1
i += 1
if bloc_to_nlink:
bloc_to_nlink.addto(asmbloc.asm_constraint(b.label,
C_NEXT))
bloc_to_nlink = None
# in bloc
elif state == 1:
if isinstance(lines[i], asmbloc.asm_raw):
if hasattr(lines[i], 'split'):
state = 0
block_may_link = False
i += 1
else:
state = 1
block_may_link = True
b.addline(lines[i])
i += 1
# asmbloc.asm_label
elif isinstance(lines[i], asmbloc.asm_label):
if block_may_link:
b.addto(
asmbloc.asm_constraint(lines[i], C_NEXT))
block_may_link = False
state = 0
# instruction
else:
b.addline(lines[i])
if lines[i].dstflow():
for x in lines[i].getdstflow(symbol_pool):
if not isinstance(x, m2_expr.ExprId):
continue
if x in mnemo.regs.all_regs_ids:
continue
b.addto(asmbloc.asm_constraint(x, C_TO))
# TODO XXX redo this really
if not lines[i].breakflow() and i + 1 < len(lines):
if isinstance(lines[i + 1], asmbloc.asm_label):
l = lines[i + 1]
else:
l = guess_next_new_label(symbol_pool)
lines[i + 1:i + 1] = [l]
else:
state = 0
if lines[i].splitflow():
bloc_to_nlink = b
if not lines[i].breakflow() or lines[i].splitflow():
block_may_link = True
else:
block_may_link = False
i += 1
for block in blocs_sections[0]:
asmbloc.log_asmbloc.info(block)
return blocs_sections, symbol_pool
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