Configuring and Managing MPE/iX Internet Services (August 2002)

Chapter 7
Samba for MPE/iX Services
Overview of Samba for MPE/iX
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The SMB messages can be categorized into four types of messages: session control, file, printer, and message.
Session control messages start, authenticate, and terminate sessions. File command controls file access and
printer command controls printer access. Message commands allow an application to send messages to or
receive messages from another host. (For example, WinPopup messages). NetBIOS names are up to 15
characters long, and are usually the name of the computer that is running NetBIOS.
Example of SMB Conversation
Figure 7-3 demonstrates the process of connecting to a file space service. The SMB Negotiate Protocol
command (NegProt) is used to decide on a protocol extension to be used with the server. The client sends a
SMB NegProt to the server. This will list the protocol dialects/protocol extensions that it understands. The
server responds with the index of the dialect that it wants to use, or 0xFFFF if none of the dialects were
acceptable.Dialects newer than the Core and CorePlus protocols supply information in the NegProt response
to indicate their capabilities such as max buffer size. The six important protocol extensions of SMB are Core,
CorePlus, LAN Manager 1.0, LM 2.0, and NT LM 0.12 and CIFS 1.0.
Figure 7-3 SMB NegProt Connection
Once a protocol has been established, the client can proceed to logon to the server. Client now sends a SMB
Session Setup command (SesssetupX), see Figure 7-4. The response indicates whether the username
password pair is valid, and if so, can provide additional information. One of the very important aspects of the
response is a User ID value that must be submitted with all the subsequent SMBs sent to the server. This is
used for user authentication.
Figure 7-4 SMB Sesssetup Connection
Client Server
NegProt command
NegProt response
Client Server
Sesssetup command
Sesssetup response