iPXE
Data Fields
ieee80211_llc_snap_header Struct Reference

The 802.2 LLC/SNAP header sent before actual data in a data frame. More...

#include <ieee80211.h>

Data Fields

u8 dsap
 Destination SAP ID. More...
 
u8 ssap
 Source SAP ID. More...
 
u8 ctrl
 Control information. More...
 
u8 oui [3]
 Organization code, usually 0. More...
 
u16 ethertype
 Ethernet Type field. More...
 

Detailed Description

The 802.2 LLC/SNAP header sent before actual data in a data frame.

This header is not acknowledged in the 802.11 standard at all; it is treated just like data for MAC-layer purposes, including fragmentation and encryption. It is actually two headers concatenated: a three-byte 802.2 LLC header indicating Subnetwork Accesss Protocol (SNAP) in both source and destination Service Access Point (SAP) fields, and a five-byte SNAP header indicating a zero OUI and two-byte Ethernet protocol type field.

Thus, an eight-byte header in which six of the bytes are redundant. Lovely, isn't it?

Definition at line 324 of file ieee80211.h.

Field Documentation

◆ dsap

u8 ieee80211_llc_snap_header::dsap

Destination SAP ID.

Definition at line 327 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

◆ ssap

u8 ieee80211_llc_snap_header::ssap

Source SAP ID.

Definition at line 328 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

◆ ctrl

u8 ieee80211_llc_snap_header::ctrl

Control information.

Definition at line 329 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

◆ oui

u8 ieee80211_llc_snap_header::oui[3]

Organization code, usually 0.

Definition at line 332 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().

◆ ethertype

u16 ieee80211_llc_snap_header::ethertype

Ethernet Type field.

Definition at line 333 of file ieee80211.h.

Referenced by net80211_ll_pull(), and net80211_ll_push().


The documentation for this struct was generated from the following file: