Implementing CIFS: The Common Internet File System

Chapter 12. The SMB Header in Detail

1st rule of Oriental Cuisine: Never look inside the eggroll.

During that first expedition into SMB territory we continually deferred, among other things, studying the finer details of the SMB header. We were trying to cover the general concepts, but now we need to dig into the guts of SMB to see how things really work. Latex gloves and lab coats required.

Let’s start by revisiting the header layout. Just for review, here’s what it looks like:

The first four bytes are constant, so we won’t worry about those. The COMMAND field is fairly straightforward too; it’s just a one byte field containing an SMB command code. ...