metasploit-framework/lib/rex/encoder/ndr.rb

91 lines
2.1 KiB
Ruby

# -*- coding: binary -*-
require "rex/text"
module Rex
module Encoder
module NDR
# Provide padding to align the string to the 32bit boundary
def NDR.align(string)
return "\x00" * ((4 - (string.length & 3)) & 3)
end
# Encode a 4 byte long
# use to encode:
# long element_1;
def NDR.long(string)
return [string].pack('V')
end
# Encode a 2 byte short
# use to encode:
# short element_1;
def NDR.short(string)
return [string].pack('v')
end
# Encode a single byte
# use to encode:
# byte element_1;
def NDR.byte(string)
return [string].pack('c')
end
# Encode a byte array
# use to encode:
# char element_1
def NDR.UniConformantArray(string)
return long(string.length) + string + align(string)
end
# Encode a string
# use to encode:
# char *element_1;
def NDR.string(string)
string << "\x00" # null pad
return long(string.length) + long(0) + long(string.length) + string + align(string)
end
# Encode a string
# use to encode:
# w_char *element_1;
def NDR.wstring(string)
string = string + "\x00" # null pad
return long(string.length) + long(0) + long(string.length) + Rex::Text.to_unicode(string) + align(Rex::Text.to_unicode(string))
end
# Encode a string and make it unique
# use to encode:
# [unique] w_char *element_1;
def NDR.uwstring(string)
string = string + "\x00" # null pad
return long(rand(0xffffffff))+long(string.length) + long(0) + long(string.length) + Rex::Text.to_unicode(string) + align(Rex::Text.to_unicode(string))
end
# Encode a string that is already unicode encoded
# use to encode:
# w_char *element_1;
def NDR.wstring_prebuilt(string)
# if the string len is odd, thats bad!
if string.length % 2 > 0
string = string + "\x00"
end
len = string.length / 2;
return long(len) + long(0) + long(len) + string + align(string)
end
# alias to wstring, going away soon
def NDR.UnicodeConformantVaryingString(string)
NDR.wstring(string)
end
# alias to wstring_prebuilt, going away soon
def NDR.UnicodeConformantVaryingStringPreBuilt(string)
NDR.wstring_prebuilt(string)
end
end
end
end