ethernet.h File Reference

#include <net/net.h>
#include <stdint.h>

Include dependency graph for ethernet.h:

Data Structures
struct	ethernet_header_t

Functions
void	ethernet_receive_frame (net_interface_t *interface, uint8_t *data, uint32_t len)
void	ethernet_send_frame (net_interface_t *interface, uint8_t dst_mac[6], uint16_t ethertype, uint8_t *data, uint32_t len)

Detailed Description

See also

https://en.wikipedia.org/wiki/Ethernet_frame

https://wiki.osdev.org/Network_Stack

Function Documentation

ethernet_receive_frame()

void ethernet_receive_frame	(	net_interface_t *	interface,
		uint8_t *	data,
		uint32_t	len )

Receives an Ethernet frame on an interface. This is a handler that gets called by the lower layer (i.e. the network driver). After having decoded the frame, this handler will likely call a handler of this layer (2) or the layer above (3).

Parameters

interface	the network interface that received the frame
data	the data containing the Ethernet frame
len	the length of the data

ethernet_send_frame()

void ethernet_send_frame	(	net_interface_t *	interface,
		uint8_t	dst_mac[6],
		uint16_t	ethertype,
		uint8_t *	data,
		uint32_t	len )

Sends an Ethernet frame over an interface.

We are at the Ethernet level, so we can only communicate with machines in the same LAN and we use MAC addresses for that. The destination MAC address is therefore used by one of the machines in the LAN, usually the DNS server or the "gateway" (but it could be any other machine for LAN exchanges). We will use the MAC address of the gateway when we will send Internet packets for instance.

Parameters

interface	the network interface used to send the frame
dst_mac	the destination MAC address
ethertype	a value indicating which protocol is encapsulated in the payload of the frame
data	the encapsulated payload
len	the length of the data