"""
Defines a class value which encapsulates the basic lldb Scripting Bridge APIs. This provides an easy
wrapper to extract information from C based constructs.
|------- core.value------------|
| |--lldb Scripting Bridge--| |
| | |--lldb core--| | |
| |-------------------------| |
|------------------------------|
Use the member function GetSBValue() to access the base Scripting Bridge value.
"""
import lldb
import re
from lazytarget import *
_cstring_rex = re.compile("((?:\s*|const\s+)\s*char(?:\s+\*|\s+[A-Za-z_0-9]*\s*\[|)\s*)",re.MULTILINE|re.DOTALL)
class value(object):
'''A class designed to wrap lldb.SBValue() objects so the resulting object
can be used as a variable would be in code. So if you have a Point structure
variable in your code in the current frame named "pt", you can initialize an instance
of this class with it:
pt = lldb.value(lldb.frame.FindVariable("pt"))
print pt
print pt.x
print pt.y
pt = lldb.value(lldb.frame.FindVariable("rectangle_array"))
print rectangle_array[12]
print rectangle_array[5].origin.x'''
def __init__(self, sbvalue):
self._sbval19k84obscure747 = sbvalue
self._sbval19k84obscure747_type = sbvalue.GetType()
self._sbval19k84obscure747_is_ptr = sbvalue.GetType().IsPointerType()
self.sbvalue = sbvalue
def __nonzero__(self):
return ( self._sbval19k84obscure747.__nonzero__() and self._GetValueAsUnsigned() != 0 )
def __repr__(self):
return self._sbval19k84obscure747.__str__()
def __cmp__(self, other):
if type(other) is int:
me = int(self)
if type(me) is long:
other = long(other)
return me.__cmp__(other)
if type(other) is value:
return int(self).__cmp__(int(other))
raise TypeError("Cannot compare value with this type")
def __str__(self):
global _cstring_rex
type_name = self._sbval19k84obscure747_type.GetName()
if len(_cstring_rex.findall(type_name)) > 0 :
return self._GetValueAsString()
summary = self._sbval19k84obscure747.GetSummary()
if summary:
return summary.strip('"')
return self._sbval19k84obscure747.__str__()
def __getitem__(self, key):
if type(key) is slice:
_start = int(key.start)
_end = int(key.stop)
_step = 1
if key.step != None:
_step = int(key.step)
retval = []
while _start < _end:
retval.append(self[_start])
_start += _step
return retval
if type(key) in (int, long):
return value(self._sbval19k84obscure747.GetValueForExpressionPath("[%i]" % key))
if type(key) is value:
return value(self._sbval19k84obscure747.GetValueForExpressionPath("[%i]" % int(key)))
raise TypeError("Cannot fetch Array item for this type")
def __getattr__(self, name):
child_sbvalue = self._sbval19k84obscure747.GetChildMemberWithName (name)
if child_sbvalue:
return value(child_sbvalue)
raise AttributeError("No field by name: "+name )
def __add__(self, other):
return int(self) + int(other)
def __radd__(self, other):
return int(self) + int(other)
def __sub__(self, other):
return int(self) - int(other)
def __rsub__(self, other):
return int(other) - int(self)
def __mul__(self, other):
return int(self) * int(other)
def __rmul__(self, other):
return int(self) * int(other)
def __floordiv__(self, other):
return int(self) // int(other)
def __mod__(self, other):
return int(self) % int(other)
def __rmod__(self, other):
return int(other) % int(self)
def __divmod__(self, other):
return int(self) % int(other)
def __rdivmod__(self, other):
return int(other) % int(self)
def __pow__(self, other):
return int(self) ** int(other)
def __lshift__(self, other):
return int(self) << int(other)
def __rshift__(self, other):
return int(self) >> int(other)
def __and__(self, other):
return int(self) & int(other)
def __rand(self, other):
return int(self) & int(other)
def __xor__(self, other):
return int(self) ^ int(other)
def __or__(self, other):
return int(self) | int(other)
def __div__(self, other):
return int(self) / int(other)
def __rdiv__(self, other):
return int(other)/int(self)
def __truediv__(self, other):
return int(self) / int(other)
def __iadd__(self, other):
result = self.__add__(other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __isub__(self, other):
result = self.__sub__(other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __imul__(self, other):
result = self.__mul__(other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __idiv__(self, other):
result = self.__div__(other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __itruediv__(self, other):
result = self.__truediv__(other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __ifloordiv__(self, other):
result = self.__floordiv__(self, other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __imod__(self, other):
result = self.__and__(self, other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __ipow__(self, other):
result = self.__pow__(self, other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __ipow__(self, other, modulo):
result = self.__pow__(self, other, modulo)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __ilshift__(self, other):
result = self.__lshift__(other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __irshift__(self, other):
result = self.__rshift__(other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __iand__(self, other):
result = self.__and__(self, other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __ixor__(self, other):
result = self.__xor__(self, other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __ior__(self, other):
result = self.__ior__(self, other)
self._sbval19k84obscure747.SetValueFromCString (str(result))
return result
def __neg__(self):
return -int(self)
def __pos__(self):
return +int(self)
def __abs__(self):
return abs(int(self))
def __invert__(self):
return ~int(self)
def __complex__(self):
return complex (int(self))
def __int__(self):
if self._sbval19k84obscure747_is_ptr:
return self._GetValueAsUnsigned()
tname= self._sbval19k84obscure747_type.GetName()
if tname.find('uint') >= 0 or tname.find('unsigned') >= 0:
return self._GetValueAsUnsigned()
retval = self._sbval19k84obscure747.GetValueAsSigned()
if (retval & 0x80000000):
retval = retval - 0x100000000
return retval
def __long__(self):
return self._sbval19k84obscure747.GetValueAsSigned()
def __float__(self):
return float (self._sbval19k84obscure747.GetValueAsSigned())
def __oct__(self):
return '0%o' % self._GetValueAsUnsigned()
def __hex__(self):
return '0x%x' % self._GetValueAsUnsigned()
def __eq__(self, other):
self_err = lldb.SBError()
other_err = lldb.SBError()
self_val = self._sbval19k84obscure747.GetValueAsUnsigned(self_err)
if self_err.fail:
raise ValueError("unable to extract value of self")
if type(other) is value:
other_val = other._sbval19k84obscure747.GetValueAsUnsigned(other_err)
if other_err.fail:
raise ValueError("unable to extract value of other")
return self_val == other_val
if type(other) is int:
return int(self) == other
raise TypeError("Equality operation is not defined for this type.")
def __neq__(self, other):
return not self.__eq__(other)
def GetSBValue(self):
return self._sbval19k84obscure747
def _GetValueAsSigned(self):
serr = lldb.SBError()
retval = self._sbval19k84obscure747.GetValueAsSigned(serr)
if serr.success:
return retval
raise ValueError("Failed to read signed data. "+ str(self._sbval19k84obscure747) +"(type =" + str(self._sbval19k84obscure747_type) + ") Error description: " + serr.GetCString())
def _GetValueAsUnsigned(self):
serr = lldb.SBError()
retval = self._sbval19k84obscure747.GetValueAsUnsigned(serr)
if serr.success:
return retval
raise ValueError("Failed to read unsigned data. "+ str(self._sbval19k84obscure747) +"(type =" + str(self._sbval19k84obscure747_type) + ") Error description: " + serr.GetCString())
def _GetValueAsString(self, offset = 0, maxlen = 1024):
serr = lldb.SBError()
sbdata = None
if self._sbval19k84obscure747.TypeIsPointerType():
sbdata = self._sbval19k84obscure747.GetPointeeData(offset, maxlen)
else:
sbdata = self._sbval19k84obscure747.GetData()
retval = ''
bytesize = sbdata.GetByteSize()
if bytesize == 0 :
return ''
for i in range(0, bytesize) :
serr.Clear()
ch = chr(sbdata.GetUnsignedInt8(serr, i))
if serr.fail :
raise ValueError("Unable to read string data: " + serr.GetCString())
if ch == '\0':
break
retval += ch
return retval
def __format__(self, format_spec):
ret_format = "{0:"+format_spec+"}"
type_spec=format_spec.strip().lower()[-1]
if type_spec == 'x':
return ret_format.format(self._GetValueAsUnsigned())
if type_spec == 'd':
return ret_format.format(int(self))
if type_spec == 's':
return ret_format.format(str(self))
if type_spec == 'o':
return ret_format.format(int(oct(self)))
if type_spec == 'c':
return ret_format.format(int(self))
return "unknown format " + format_spec + str(self)
def unsigned(val):
""" Helper function to get unsigned value from core.value
params: val - value (see value class above) representation of an integer type
returns: int which is unsigned.
raises : ValueError if the type cannot be represented as unsigned int.
"""
if type(val) is value:
return val._GetValueAsUnsigned()
return int(val)
def sizeof(t):
""" Find the byte size of a type.
params: t - str : ex 'time_spec' returns equivalent of sizeof(time_spec) in C
t - value: ex a value object. returns size of the object
returns: int - byte size length
"""
if type(t) is value :
return t.GetSBValue().GetByteSize()
if type(t) is str:
return gettype(t).GetByteSize()
raise ValueError("Cannot get sizeof. Invalid argument")
def dereference(val):
""" Get a dereferenced obj for a pointer type obj
params: val - value object representing a pointer type C construct in lldb
returns: value - value
ex. val = dereference(ptr_obj) #python
is same as
obj_ptr = (int *)0x1234 #C
val = *obj_ptr #C
"""
if type(val) is value and val.GetSBValue().TypeIsPointerType():
return value(val.GetSBValue().Dereference())
raise TypeError('Cannot dereference this type.')
def addressof(val):
""" Get address of a core.value object.
params: val - value object representing a C construct in lldb
returns: value - value object referring to 'type(val) *' type
ex. addr = addressof(hello_obj) #python
is same as
uintptr_t addr = (uintptr_t)&hello_obj #C
"""
if type(val) is value:
return value(val.GetSBValue().AddressOf())
raise TypeError("Cannot do addressof for non-value type objects")
def cast(obj, target_type):
""" Type cast an object to another C type.
params:
obj - core.value object representing some C construct in lldb
target_type - str : ex 'char *'
- lldb.SBType :
"""
dest_type = target_type
if type(target_type) is str:
dest_type = gettype(target_type)
elif type(target_type) is value:
dest_type = target_type.GetSBValue().GetType()
if type(obj) is value :
return value(obj.GetSBValue().Cast(dest_type))
elif type(obj) is int:
print "ERROR: You cannot cast an 'int' to %s, please use kern.GetValueFromAddress() for such purposes." % str(target_type)
raise TypeError("object of type %s cannot be casted to %s" % (str(type(obj)), str(target_type)))
_value_types_cache={}
def gettype(target_type):
""" Returns lldb.SBType of the given target_type
params:
target_type - str, ex. 'char', 'uint32_t' etc
returns:
lldb.SBType - SBType corresponding to the given target_type
raises:
NameError - Incase the type is not identified
"""
global _value_types_cache
target_type = target_type.replace('struct', '')
target_type = str(target_type).strip()
if target_type not in _value_types_cache:
tmp_type = None
if target_type.endswith('*') :
tmp_type = LazyTarget.GetTarget().FindFirstType(target_type.rstrip('*').strip())
if not tmp_type.IsValid():
raise NameError('Unable to Cast to type '+target_type)
tmp_type = tmp_type.GetPointerType()
else :
tmp_type = LazyTarget.GetTarget().FindFirstType(target_type)
if not tmp_type.IsValid():
raise NameError('Unable to Cast to type '+target_type)
_value_types_cache[target_type] = tmp_type
return _value_types_cache[target_type]
def getfieldoffset(struct_type, field_name):
""" Returns the byte offset of a field inside a given struct
params:
struct_type - str or lldb.SBType, ex. 'struct ipc_port *' or port.gettype()
field_name - str, name of the field inside the struct ex. 'ip_messages'
returns:
int - byte offset of the field_name inside the struct_type
raises:
TypeError - - In case the struct_type has no field with the name field_name
"""
if type(struct_type) == str:
struct_type = gettype(struct_type)
offset = 0
for field in struct_type.get_fields_array():
if str(field.GetName()) == field_name:
return field.GetOffsetInBytes()
raise TypeError('Field name "%s" not found in type "%s"' % (field_name, str(struct_type)))
def islong(x):
""" Returns True if a string represents a long integer, False otherwise
"""
try:
long(x,16)
except ValueError:
try:
long(x)
except ValueError:
return False
return True