Class: Rex::Zip::Entry

Inherits:
Object
  • Object
show all
Defined in:
lib/rex/zip/entry.rb

Overview

An Entry represents a logical file or directory to be stored in an Archive

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(fname, data, compmeth, timestamp = nil, attrs = nil, xtra = nil, comment = nil) ⇒ Entry

Returns a new instance of Entry.



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# File 'lib/rex/zip/entry.rb', line 16

def initialize(fname, data, compmeth, timestamp=nil, attrs=nil, xtra=nil, comment=nil)
	@name = fname
	@data = data
	@xtra = xtra
	@xtra ||= ''
	@comment = comment
	@comment ||= ''
	@attrs = attrs
	@attrs ||= 0

	# XXX: sanitize timestmap (assume now)
	timestamp ||= Time.now
	@flags = CompFlags.new(0, compmeth, timestamp)

	if (@data)
		compress
	else
		@data = ''
		@info = CompInfo.new(0, 0, 0)
	end
	@compdata ||= ''
end

Instance Attribute Details

#attrs ⇒ Object

Returns the value of attribute attrs.



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# File 'lib/rex/zip/entry.rb', line 13

def attrs
  @attrs
end

#comment ⇒ Object

Returns the value of attribute comment.



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# File 'lib/rex/zip/entry.rb', line 13

def comment
  @comment
end

#data ⇒ Object

Returns the value of attribute data.



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# File 'lib/rex/zip/entry.rb', line 14

def data
  @data
end

#flags ⇒ Object

Returns the value of attribute flags.



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# File 'lib/rex/zip/entry.rb', line 13

def flags
  @flags
end

#info ⇒ Object

Returns the value of attribute info.



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# File 'lib/rex/zip/entry.rb', line 13

def info
  @info
end

#name ⇒ Object

Returns the value of attribute name.



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# File 'lib/rex/zip/entry.rb', line 13

def name
  @name
end

#xtra ⇒ Object

Returns the value of attribute xtra.



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# File 'lib/rex/zip/entry.rb', line 13

def xtra
  @xtra
end

Instance Method Details

#compress ⇒ Object

Compress the #data and store it for later use. If this entry’s compression method produces a larger blob than the original data, the method is changed to CM_STORE.



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# File 'lib/rex/zip/entry.rb', line 48

def compress
	@crc = Zlib.crc32(@data, 0)
	case @flags.compmeth

	when CM_STORE
		@compdata = @data

	when CM_DEFLATE
		z = Zlib::Deflate.new(Zlib::BEST_COMPRESSION)
		@compdata = z.deflate(@data, Zlib::FINISH)
		z.close
		@compdata = @compdata[2, @compdata.length-6]

	else
		raise 'Unsupported compression method: %u' % @flags.compmeth
	end

	# if compressing doesn't help, just store it
	if (@compdata.length > @data.length)
		@compdata = @data
		@flags.compmeth = CM_STORE
	end

	@info = CompInfo.new(@crc, @compdata.length, @data.length)
end

#inspect ⇒ Object 



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# File 'lib/rex/zip/entry.rb', line 107

def inspect
	"#<#{self.class} name:#{name}, data:#{@data.length} bytes>"
end

#pack ⇒ Object

Return the compressed data in a format suitable for adding to an Archive



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# File 'lib/rex/zip/entry.rb', line 86

def pack
	ret = ''

	#  - lfh 1
	lfh = LocalFileHdr.new(self)
	ret << lfh.pack

	#  - data 1
	if (@compdata)
		ret << @compdata
	end

	if (@gpbf & GPBF_USE_DATADESC)
		#  - data desc 1
		dd = DataDesc.new(@info)
		ret << dd.pack
	end

	ret
end

#relative_path ⇒ Object 



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# File 'lib/rex/zip/entry.rb', line 75

def relative_path
	if (@name[0,1] == '/')
		return @name[1,@name.length]
	end
	@name
end