Add more comments to fake_code_signer.rb

Author: banister

test/fake_code_signer.rb

@@ -32,9 +32,17 @@ def sign
       raise "input and output files must be different!"
     end
 
+	# Below we access an instance of the IMAGE_DATA_DIRECTORY struct.
+	# This instance is called IMAGE_DIRECTORY_ENTRY_SECURITY and it contains information about the digital signature
+	# see: https://msdn.microsoft.com/en-us/library/windows/desktop/ms680305(v=vs.85).aspx	
+	
+	# write the offset (address) of the digital signature to the security header (VirtualAddress field)
     @image[pe_header.security_offset, 4] = raw_bytes(@image.size + @padding)
 
+	# write the size of the digital signature to the security header (Size field)
     @image[pe_header.security_offset + 4, 4] = raw_bytes(FAKE_SIG.size)
+	
+	# append the "digital signature" to the end of the executable, complete with padding 
     @image << padding_string << FAKE_SIG
 
     File.binwrite(@output, @image)