def decode(instruction):
'''Extract the modrm tuple out of the provided instruction'''
modrm = instruction[2]
if len(modrm) > 0:
modrm = decoder.decodeInteger(modrm)
return decoder.extractmodrm(modrm)
return None
def decode(instruction):
'''Extract the modrm tuple out of the provided instruction'''
modrm = instruction[2]
if len(modrm) > 0:
modrm = decoder.decodeInteger(modrm)
return decoder.extractmodrm(modrm)
return None
def promoteBranch_16(instruction):
raise NotImplementedError("16-bit absolute branches not implemented really")
result = promoteBranch_32(instruction)
imm = getImmediate(result)
offset = decodeInteger(imm, True) - length(result)
# downgrade the opcode
prefix = getPrefix(result)
if '\x66' not in prefix:
prefix += '\x66'
result = setPrefix(result, prefix)
offset += length(result)
return setImmediate(result, encodeInteger(offset, 2))
def promoteBranch_16(instruction):
raise NotImplementedError(
"16-bit absolute branches not implemented really")
result = promoteBranch_32(instruction)
imm = getImmediate(result)
offset = decodeInteger(imm, True) - length(result)
# downgrade the opcode
prefix = getPrefix(result)
if '\x66' not in prefix:
prefix += '\x66'
result = setPrefix(result, prefix)
offset += length(result)
return setImmediate(result, encodeInteger(offset, 2))
def getRelativeAddress(pc, instruction):
'''Given the specified instruction and address, will return the target branch address'''
imm = getImmediate(instruction)
l = len(imm)
ofs = decodeInteger(imm)
pc += length(instruction)
if (l == 4) and (ofs & 0x80000000):
return pc - (0x100000000 - ofs)
elif (l == 2) and (ofs & 0x8000):
return pc - (0x10000 - ofs)
elif (l == 1) and (ofs & 0x80):
return pc - (0x100 - ofs)
# otherwise we're just jumping forward
return pc + ofs
def promoteBranch_32(instruction):
imm = getImmediate(instruction)
offset = decodeInteger(imm, True) + length(instruction)
prefix = ''.join([x for x in getPrefix(instruction) if x != '\x66'])
if isConditionalBranch8(instruction):
column = ord(getOpcode(instruction)) & 0xf
result = setOpcode(instruction, '\x0f'+chr(column | 0x80))
elif isUnconditionalBranch8(instruction):
result = setOpcode(instruction, '\xe9')
elif isRelativeCall(instruction) or isUnconditionalBranch(instruction) or isConditionalBranch(instruction):
result = instruction
else:
raise NotImplementedError('Unable to promote a non-branch instruction to 32-bits: {!r}'.format(n))
result = setPrefix(setImmediate(result, '\x00\x00\x00\x00'), prefix)
return setImmediate(result, encodeInteger(offset-length(result), 4))
def getRelativeAddress(pc, instruction):
'''Given the specified instruction and address, will return the target branch address'''
imm = getImmediate(instruction)
l = len(imm)
ofs = decodeInteger(imm)
pc += length(instruction)
if (l == 4) and (ofs & 0x80000000):
return pc - (0x100000000 - ofs)
elif (l == 2) and (ofs & 0x8000):
return pc - (0x10000 - ofs)
elif (l == 1) and (ofs & 0x80):
return pc - (0x100 - ofs)
# otherwise we're just jumping forward
return pc + ofs
def promoteBranch_8(instruction):
'''Promote(?) instruction to an 8-bit branch'''
imm = getImmediate(instruction)
offset = decodeInteger(imm, True)
prefix = ''.join([x for x in getPrefix(instruction) if x != '\x66'])
if isConditionalBranch8(instruction) or isUnconditionalBranch8(instruction) or isRelativeCall(instruction):
result = instruction
offset += length(result)
elif isUnconditionalBranch(instruction):
result = setOpcode(instruction, '\xeb')
elif isConditionalBranch(instruction):
column = ord(getOpcode(instruction)[1]) & 0xf
result = setOpcode(instruction, chr(column | 0x70))
else:
raise NotImplementedError('Unable to promote a non-branch instruction to 8-bits: {!r}'.format(n))
result = setPrefix(setImmediate(result, '\x00'), prefix)
return setImmediate(result, encodeInteger(offset-length(result), 1))
def getDelta(insn):
p,o,m,s,d,i = insn
opcode = decoder.decodeInteger(o[-1])
if len(o) == 2:
opcode = 0x100 + opcode
try:
return stacktable[opcode](insn)
except KeyError:
pass
if m:
mod,reg,rm = modrm.decode(insn)
if mod == 3 and reg == 4:
raise NotImplementedError("arithmetic instruction references esp, but is not yet implemented")
pass
if sib:
scale,index,base = sib.decode(insn)
if base == 4:
raise NotImplementedError("read from esp")
pass
return 0
def getDelta(insn):
p,o,m,s,d,i = insn
opcode = decoder.decodeInteger(o[-1])
if len(o) == 2:
opcode = 0x100 + opcode
try:
return stacktable[opcode](insn)
except KeyError:
pass
if m:
mod,reg,rm = modrm.decode(insn)
if mod == 3 and reg == 4:
raise NotImplementedError("arithmetic instruction references esp, but is not yet implemented")
pass
if sib:
scale,index,base = sib.decode(insn)
if base == 4:
raise NotImplementedError("read from esp")
pass
return 0
def promoteBranch_32(instruction):
imm = getImmediate(instruction)
offset = decodeInteger(imm, True) + length(instruction)
prefix = ''.join([x for x in getPrefix(instruction) if x != '\x66'])
if isConditionalBranch8(instruction):
column = ord(getOpcode(instruction)) & 0xf
result = setOpcode(instruction, '\x0f' + chr(column | 0x80))
elif isUnconditionalBranch8(instruction):
result = setOpcode(instruction, '\xe9')
elif isRelativeCall(instruction) or isUnconditionalBranch(
instruction) or isConditionalBranch(instruction):
result = instruction
else:
raise NotImplementedError(
'Unable to promote a non-branch instruction to 32-bits: {!r}'.
format(n))
result = setPrefix(setImmediate(result, '\x00\x00\x00\x00'), prefix)
return setImmediate(result, encodeInteger(offset - length(result), 4))
def promoteBranch_8(instruction):
'''Promote(?) instruction to an 8-bit branch'''
imm = getImmediate(instruction)
offset = decodeInteger(imm, True)
prefix = ''.join([x for x in getPrefix(instruction) if x != '\x66'])
if isConditionalBranch8(instruction) or isUnconditionalBranch8(
instruction) or isRelativeCall(instruction):
result = instruction
offset += length(result)
elif isUnconditionalBranch(instruction):
result = setOpcode(instruction, '\xeb')
elif isConditionalBranch(instruction):
column = ord(getOpcode(instruction)[1]) & 0xf
result = setOpcode(instruction, chr(column | 0x70))
else:
raise NotImplementedError(
'Unable to promote a non-branch instruction to 8-bits: {!r}'.
format(n))
result = setPrefix(setImmediate(result, '\x00'), prefix)
return setImmediate(result, encodeInteger(offset - length(result), 1))
def retn(insn):
p,o,m,s,d,i = insn
if len(i) == 0:
return 4
return 4 + decoder.decodeInteger(i)
def stringToNumber(string):
'''This function name is deprecated in favor of encodeInteger'''
return decodeInteger(string)
def extractsib(instruction):
'''Returns (scale,index,base) of an instruction'''
sib = getSib(instruction)
return decoder.extractsib( decodeInteger(sib) )
def extractmodrm(instruction):
'''Return the (Mod, Reg, r/m) components of an instruction'''
modrm = getModrm(instruction)
return decoder.extractmodrm( decodeInteger(modrm) )
code = '\xe9\xc1\xfe\xff\xff'
test_set(0x101d70e9, code, 0x101d6faf)
@TestCase
def Test_f():
code = '\xe9\xa6\x00\x00\x00'
test_set(0x101dc252, code, 0x101dc2fd)
if False:
code = '\x0f\x85\x7f\xff\xff\xff'
n = setRelativeAddress(0, decode(code), -5)
print hex(getRelativeAddress(0, n))
n = setRelativeAddress(0, decode(code), 0x2)
print repr(n)
print hex(getRelativeAddress(0, n))
print hex(decodeInteger(getImmediate(n)) + length(n))
if False:
code = '\x77\x08'
code = '\x0f\x87\x04\x00\x00\x00'
n = decode(code)
x = promoteBranch_8(n)
print repr(x)
print '%x:%x -> %x' % (0x70, 0x72, 0x7a)
@TestCase
def Test_10():
res = '''
b8b5000000ba0003fe7fff12c20c00b8b6000000ba0003fe7fff12c21800b8b7000000ba0003fe7fff12c22400b8b8000000ba0003fe7fff12c22400b8b9000000ba0003fe7fff12c21800b8ba000000ba0003fe7fff12c21400b8bb000000ba0003fe7fff12c20400b8bc000000ba0003fe7fff12c20800b8bd000000ba0003fe7fff12c20c00b8be000000ba0003fe7fff12c21400
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
code = '\xe9\xc1\xfe\xff\xff'
test_set( 0x101d70e9, code, 0x101d6faf )
@TestCase
def Test_f():
code = '\xe9\xa6\x00\x00\x00'
test_set( 0x101dc252, code, 0x101dc2fd )
if False:
code = '\x0f\x85\x7f\xff\xff\xff'
n = setRelativeAddress(0, decode(code), -5)
print hex(getRelativeAddress(0, n))
n = setRelativeAddress(0, decode(code), 0x2)
print repr(n)
print hex(getRelativeAddress(0, n))
print hex(decodeInteger(getImmediate(n)) + length(n))
if False:
code = '\x77\x08'
code = '\x0f\x87\x04\x00\x00\x00'
n = decode(code)
x = promoteBranch_8(n)
print repr(x)
print '%x:%x -> %x'% (0x70, 0x72, 0x7a)
@TestCase
def Test_10():
res = '''
b8b5000000ba0003fe7fff12c20c00b8b6000000ba0003fe7fff12c21800b8b7000000ba0003fe7fff12c22400b8b8000000ba0003fe7fff12c22400b8b9000000ba0003fe7fff12c21800b8ba000000ba0003fe7fff12c21400b8bb000000ba0003fe7fff12c20400b8bc000000ba0003fe7fff12c20800b8bd000000ba0003fe7fff12c20c00b8be000000ba0003fe7fff12c21400
6a1468082d917ce85cbcffff8a1dc0e1977c8b750c33d23bf20f85f81602008b7d103bfa740289178b4d08f7c1fcffffff0f851cbb02003bfa0f842dbb02008bc183e0020f85d416020084db754a33db4384cb0f84821d00006878e1977c3bc20f8597170200e832e3feff85f60f8536bb020064a118000000b9d8e0977cf00fc1194381e3ffff00008b402425ff0f0000c1e0100bd8891f33f68bc6e802bcffffc20c0090ffffffff43e8937c5ee8937c90909090906a0c68802d917ce8a6bbffff8b5508f7c2feffffff0f85b8bb02008b4d0c85c97436f7c1000000f00f85bebb020064a118000000c1e91033482466f7c1ff0f0f85a7bb0200f6c2010f84107a01006878e1977ce86fe3feff33c0e88ebbffffc208009090909090ffffffff23e9937c3ee9937c90909090908bff558bec8b45145333db3bc3568b75080f8c04b60200895e048bc8c1e1100bc88b
def retf(insn):
p,o,m,s,d,i = insn
if len(i) == 0:
return 6
return 6 + decoder.decodeInteger(i)
def retn(insn):
p,o,m,s,d,i = insn
if len(i) == 0:
return 4
return 4 + decoder.decodeInteger(i)
def retf(insn):
p,o,m,s,d,i = insn
if len(i) == 0:
return 6
return 6 + decoder.decodeInteger(i)
def stringToNumber(string):
'''This function name is deprecated in favor of encodeInteger'''
return decodeInteger(string)
def extractsib(instruction):
'''Returns (scale,index,base) of an instruction'''
sib = getSib(instruction)
return decoder.extractsib(decodeInteger(sib))
def extractmodrm(instruction):
'''Return the (Mod, Reg, r/m) components of an instruction'''
modrm = getModrm(instruction)
return decoder.extractmodrm(decodeInteger(modrm))