Port of the python Manifest.mbdb parser

git-svn-id: file:///home/svn/framework3/trunk@12424 4d416f70-5f16-0410-b530-b9f4589650da

lib/rex/parser/apple_backup_manifestdb.rb

@@ -0,0 +1,125 @@
+#
+# This is a Ruby port of the Python manifest parsing code posted to:
+# 	http://stackoverflow.com/questions/3085153/how-to-parse-the-manifest-mbdb-file-in-an-ios-4-0-itunes-backup/3130860#3130860
+#
+
+class AppleBackupManifestDB
+
+	attr_accessor :entry_offsets
+	attr_accessor :entries
+	attr_accessor :mbdb, :mbdx
+	attr_accessor :mbdb_data, :mbdx_data
+	attr_accessor :mbdb_offset, :mbdx_offset
+	
+	def initialize(mbdb_data, mbdx_data)	
+		self.entries = {}
+		self.entry_offsets = {}
+		self.mbdb_data = mbdb_data
+		self.mbdx_data = mbdx_data
+		parse_mbdb
+		parse_mbdx
+	end
+	
+	def self.from_files(mbdb_file, mbdx_file)
+		mbdb_data = ""
+		::File.open(mbdb_file, "rb") {|fd| mbdb_data = fd.read(fd.stat.size) }
+		mbdx_data = ""
+		::File.open(mbdx_file, "rb") {|fd| mbdx_data = fd.read(fd.stat.size) }
+		
+		self.new(mbdb_data, mbdx_data)
+	end
+	
+	def parse_mbdb
+		raise ArgumentError, "Not valid MBDB data" if self.mbdb_data[0,4] != "mbdb"	
+		self.mbdb_offset = 4
+		self.mbdb_offset = self.mbdb_offset + 2 # Maps to \x05 \x00 (unknown)
+
+		while self.mbdb_offset < self.mbdb_data.length
+			info = {}
+			info[:start_offset] = self.mbdb_offset
+			info[:domain]       = mbdb_read_string
+			info[:filename]     = mbdb_read_string			
+			info[:linktarget]   = mbdb_read_string			
+			info[:datahash]     = mbdb_read_string
+			info[:unknown1]     = mbdb_read_string
+			info[:mode]         = mbdb_read_int(2)
+			info[:unknown2]     = mbdb_read_int(4)			
+			info[:unknown3]     = mbdb_read_int(4)				
+			info[:uid]          = mbdb_read_int(4)				
+			info[:gid]          = mbdb_read_int(4)				
+			info[:mtime]        = Time.at(mbdb_read_int(4))
+			info[:atime]        = Time.at(mbdb_read_int(4))
+			info[:ctime]        = Time.at(mbdb_read_int(4))
+			info[:length]       = mbdb_read_int(8)	
+			info[:flag]         = mbdb_read_int(1)
+			property_count      = mbdb_read_int(1)
+			info[:properties]   = {}
+			1.upto(property_count) do |i|
+				k = mbdb_read_string
+				v = mbdb_read_string
+				info[:properties][k] = v
+			end
+			self.entry_offsets[ info[:start_offset] ] = info
+		end
+		self.mbdb_data = ""
+	end
+    	
+	def parse_mbdx
+		raise ArgumentError, "Not a valid MBDX file" if self.mbdx_data[0,4] != "mbdx"
+
+		self.mbdx_offset = 4
+		self.mbdx_offset = self.mbdx_offset + 2 # Maps to \x02 \x00 (unknown)
+
+		file_count = mbdx_read_int(4)
+
+		while self.mbdx_offset < self.mbdx_data.length
+			file_id = self.mbdx_data[self.mbdx_offset, 20].unpack("C*").map{|c| "%02x" % c}.join
+			self.mbdx_offset += 20
+			entry_offset = mbdx_read_int(4) + 6
+			mode = mbdx_read_int(2)
+			entry = entry_offsets[ entry_offset ]
+			# May be corrupted if there is no matching entry, but what to do about it?
+			next if not entry
+			self.entries[file_id] = entry.merge({:mbdx_mode => mode, :file_id => file_id})
+		end
+		self.mbdx_data = ""
+	end
+	
+	def mbdb_read_string
+		raise RuntimeError, "Corrupted MBDB file" if self.mbdb_offset > self.mbdb_data.length
+		len = self.mbdb_data[self.mbdb_offset, 2].unpack("n")[0]
+		self.mbdb_offset += 2
+		return '' if len == 65535
+		val = self.mbdb_data[self.mbdb_offset, len]
+		self.mbdb_offset += len
+		return val
+	end
+	
+	def mbdb_read_int(size)
+		val = 0
+		size.downto(1) do |i|
+			val = (val << 8) + self.mbdb_data[self.mbdb_offset, 1].unpack("C")[0]
+			self.mbdb_offset += 1
+		end
+ 		val
+	end
+	
+	def mbdx_read_string
+		raise RuntimeError, "Corrupted MBDX file" if self.mbdx_offset > self.mbdx_data.length
+		len = self.mbdx_data[self.mbdx_offset, 2].unpack("n")[0]
+		self.mbdx_offset += 2
+		return '' if len == 65535
+		val = self.mbdx_data[self.mbdx_offset, len]
+		self.mbdx_offset += len
+		return val
+	end
+	
+	def mbdx_read_int(size)
+		val = 0
+		size.downto(1) do |i|
+			val = (val << 8) + self.mbdx_data[self.mbdx_offset, 1].unpack("C")[0]
+			self.mbdx_offset += 1
+		end
+ 		val
+	end
+end