def get_value (elem, root):
if elem.tag == "literal" or elem.tag == "number" or elem.tag == "keyword":
return unescapeHTMLEntities(elem.text)
elif elem.tag == "string":
return unescapeHTMLEntities(elem.text.decode('base64'))
elif elem.tag == "ref":
#find the referenced object and return its value
obj = get_ref_object(elem.get('id'), root)
return get_value(obj[0], root)
elif elem.tag == "stream":
return unescapeHTMLEntities(elem[1].text.decode('base64'))
elif elem.tag == "dict":
#build the dictionary
ret = {}
size = elem.get("size")
size = re.sub("%", "", size)
dict_elems = elem.getchildren()
for i in range(int(size)):
val = get_value(dict_elems[i][0], root)
if val is not None:
ret[dict_elems[i].tag] = val
elif elem.tag == "list":
#build the list
ret = []
size = elem.get("size")
size = re.sub("%", "", size)
list_elems = elem.getchildren()
for i in range(int(size)):
val = get_value(list_elems[i], root)
if val is not None:
ret.append(val)
else:
#some tags not accounted for: Rect, field, xfa, Media, etc
ret = None
return ret
def isJavascript(content):
'''
Given an string this method looks for typical Javscript strings and try to identify if the string contains Javascript code or not.
@param content: A string
@return: A boolean, True if it seems to contain Javascript code or False in the other case
'''
JSStrings = ['var ',';',')','(','function ','=','{','}','if ','else','return','while ','for ',',','eval', 'unescape', '.replace']
keyStrings = [';','(',')']
stringsFound = []
limit = 15
minDistinctStringsFound = 5
results = 0
content = unescapeHTMLEntities(content)
if re.findall(reJSscript, content, re.DOTALL | re.IGNORECASE) != []:
return True
for char in content:
if (ord(char) < 32 and char not in ['\n','\r','\t','\f','\x00']) or ord(char) >= 127:
return False
for string in JSStrings:
cont = content.count(string)
results += cont
if cont > 0 and string not in stringsFound:
stringsFound.append(string)
elif cont == 0 and string in keyStrings:
return False
if results > limit and len(stringsFound) >= minDistinctStringsFound:
return True
else:
return False