MoinMoin: attachment:PHPUnserialize.py of GregBell/SingleSignOnSmf

   1 import types, string, re
   2 
   3 """
   4 Unserialize class for the PHP serialization format.
   5 
   6 @version v0.4 BETA
   7 @author Scott Hurring; scott at hurring dot com
   8 @copyright Copyright (c) 2005 Scott Hurring
   9 @license http://opensource.org/licenses/gpl-license.php GNU Public License
  10 $Id: PHPUnserialize.py,v 1.1 2006/01/08 21:53:19 shurring Exp $
  11 
  12 Most recent version can be found at:
  13 http://hurring.com/code/python/phpserialize/
  14 
  15 Usage:
  16 # Create an instance of the unserialize engine
  17 u = PHPUnserialize()
  18 # unserialize some string into python data
  19 data = u.unserialize(serialized_string)
  20 
  21 Please see README.txt for more information.
  22 """
  23 
  24 class PHPUnserialize(object):
  25 	"""
  26 	Class to unserialize something from the PHP Serialize format.
  27 
  28 	Usage:
  29 	u = PHPUnserialize()
  30 	data = u.unserialize(serialized_string)
  31 	"""
  32 
  33 	def __init__(self):
  34 		pass
  35 
  36 	def session_decode(self, data):
  37 		"""Thanks to Ken Restivo for suggesting the addition
  38 		of session_encode
  39 		"""
  40 		session = {}
  41 		while len(data) > 0:
  42 			m = re.match('^(\w+)\|', data)
  43 			if m:
  44 				key = m.group(1)
  45 				offset = len(key)+1
  46 				(dtype, dataoffset, value) = self._unserialize(data, offset)
  47 				offset = offset + dataoffset
  48 				data = data[offset:]
  49 				session[key] = value
  50 			else:
  51 				# No more stuff to decode 
  52 				return session
  53 		
  54 		return session
  55 		
  56 	def unserialize(self, data):
  57 		return self._unserialize(data, 0)[2]
  58 
  59 	def _unserialize(self, data, offset=0):
  60 		"""
  61 		Find the next token and unserialize it.
  62 		Recurse on array.
  63 
  64 		offset = raw offset from start of data
  65 		
  66 		return (type, offset, value)
  67 		"""
  68 
  69 		buf = []
  70 		dtype = string.lower(data[offset:offset+1])
  71 
  72 		#print "# dtype =", dtype
  73 
  74 		# 't:' = 2 chars
  75 		dataoffset = offset + 2
  76 		typeconvert = lambda x : x
  77 		chars = datalength = 0
  78 
  79  		# int => Integer
  80 		if dtype == 'i':
  81 			typeconvert = lambda x : int(x)
  82 			(chars, readdata) = self.read_until(data, dataoffset, ';')
  83 			# +1 for end semicolon
  84 			dataoffset += chars + 1
  85 
  86  		# bool => Boolean
  87 		elif dtype == 'b':
  88 			typeconvert = lambda x : (int(x) == 1)
  89 			(chars, readdata) = self.read_until(data, dataoffset, ';')
  90 			# +1 for end semicolon
  91 			dataoffset += chars + 1
  92 
  93 		# double => Floating Point
  94 		elif dtype == 'd':
  95 			typeconvert = lambda x : float(x)
  96 			(chars, readdata) = self.read_until(data, dataoffset, ';')
  97 			# +1 for end semicolon
  98 			dataoffset += chars + 1
  99 
 100 		# n => None
 101 		elif dtype == 'n':
 102 			readdata = None
 103 
 104 		# s => String
 105 		elif dtype == 's':
 106 			(chars, stringlength) = self.read_until(data, dataoffset, ':')
 107 			# +2 for colons around length field
 108 			dataoffset += chars + 2
 109 
 110 			# +1 for start quote
 111 			(chars, readdata) = self.read_chars(data, dataoffset+1, int(stringlength))
 112 			# +2 for endquote semicolon
 113 			dataoffset += chars + 2
 114 
 115 			if chars != int(stringlength) != int(readdata):
 116 				raise Exception("String length mismatch")
 117 
 118 		# array => Dict
 119 		# If you originally serialized a Tuple or List, it will
 120 		# be unserialized as a Dict.  PHP doesn't have tuples or lists,
 121 		# only arrays - so everything has to get converted into an array
 122 		# when serializing and the original type of the array is lost
 123 		elif dtype == 'a':
 124 			readdata = {}
 125 
 126 			# How many keys does this list have?
 127 			(chars, keys) = self.read_until(data, dataoffset, ':')
 128 			# +2 for colons around length field
 129 			dataoffset += chars + 2
 130 
 131 			# Loop through and fetch this number of key/value pairs
 132 			for i in range(0, int(keys)):
 133 				# Read the key
 134 				(ktype, kchars, key) = self._unserialize(data, dataoffset)
 135 				dataoffset += kchars
 136 				#print "Key(%i) = (%s, %i, %s) %i" % (i, ktype, kchars, key, dataoffset)
 137 
 138 				# Read value of the key
 139 				(vtype, vchars, value) = self._unserialize(data, dataoffset)
 140 				dataoffset += vchars
 141 				#print "Value(%i) = (%s, %i, %s) %i" % (i, vtype, vchars, value, dataoffset)
 142 
 143 				# Set the list element
 144 				readdata[key] = value
 145 
 146 				# +1 for end semicolon
 147 			dataoffset += 1
 148 			#chars = int(dataoffset) - start
 149 
 150 		# I don't know how to unserialize this
 151 		else:
 152 			raise Exception("Unknown / Unhandled data type (%s)!" % dtype)
 153 
 154 
 155 		return (dtype, dataoffset-offset, typeconvert(readdata))
 156 
 157 	def read_until(self, data, offset, stopchar):
 158 		"""
 159 		Read from data[offset] until you encounter some char 'stopchar'.
 160 		"""
 161 		buf = []
 162 		char = data[offset:offset+1]
 163 		i = 2
 164 		while char != stopchar:
 165 			# Consumed all the characters and havent found ';'
 166 			if i+offset > len(data):
 167 				raise Exception("Invalid")
 168 			buf.append(char)
 169 			char = data[offset+(i-1):offset+i]
 170 			i += 1
 171 
 172 		# (chars_read, data)
 173 		return (len(buf), "".join(buf))
 174 
 175 	def read_chars(self, data, offset, length):
 176 		"""
 177 		Read 'length' number of chars from data[offset].
 178 		"""
 179 		buf = []
 180 		# Account for the starting quote char
 181 		#offset += 1
 182 		for i in range(0, length):
 183 			char = data[offset+(i-1):offset+i]
 184 			buf.append(char)
 185 
 186 		# (chars_read, data)
 187 		return (len(buf), "".join(buf))