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#ifndef _GPXE_NETDEVICE_H
#define _GPXE_NETDEVICE_H
/** @file
*
* Network device management
*
*/
#include <stdint.h>
#include <gpxe/list.h>
#include <gpxe/tables.h>
struct pk_buff;
struct net_device;
struct net_protocol;
struct ll_protocol;
/** Maximum length of a link-layer address */
#define MAX_LL_ADDR_LEN 6
/** Maximum length of a link-layer header */
#define MAX_LL_HEADER_LEN 16
/** Maximum length of a network-layer address */
#define MAX_NET_ADDR_LEN 4
/**
* A network-layer protocol
*
*/
struct net_protocol {
/** Protocol name */
const char *name;
/**
* Process received packet
*
* @v pkb Packet buffer
* @v netdev Network device
* @v ll_source Link-layer source address
*
* This method takes ownership of the packet buffer.
*/
int ( * rx ) ( struct pk_buff *pkb, struct net_device *netdev,
const void *ll_source );
/**
* Transcribe network-layer address
*
* @v net_addr Network-layer address
* @ret string Human-readable transcription of address
*
* This method should convert the network-layer address into a
* human-readable format (e.g. dotted quad notation for IPv4).
*
* The buffer used to hold the transcription is statically
* allocated.
*/
const char * ( *ntoa ) ( const void * net_addr );
/** Network-layer protocol
*
* This is an ETH_P_XXX constant, in network-byte order
*/
uint16_t net_proto;
/** Network-layer address length */
uint8_t net_addr_len;
};
/**
* A link-layer protocol
*
*/
struct ll_protocol {
/** Protocol name */
const char *name;
/**
* Transmit network-layer packet via network device
*
* @v pkb Packet buffer
* @v netdev Network device
* @v net_protocol Network-layer protocol
* @v ll_dest Link-layer destination address
* @ret rc Return status code
*
* This method should prepend in the link-layer header
* (e.g. the Ethernet DIX header) and transmit the packet.
* This method takes ownership of the packet buffer.
*/
int ( * tx ) ( struct pk_buff *pkb, struct net_device *netdev,
struct net_protocol *net_protocol,
const void *ll_dest );
/**
* Handle received packet
*
* @v pkb Packet buffer
* @v netdev Network device
*
* This method should strip off the link-layer header
* (e.g. the Ethernet DIX header) and pass the packet to
* net_rx(). This method takes ownership of the packet
* buffer.
*/
int ( * rx ) ( struct pk_buff *pkb, struct net_device *netdev );
/**
* Transcribe link-layer address
*
* @v ll_addr Link-layer address
* @ret string Human-readable transcription of address
*
* This method should convert the link-layer address into a
* human-readable format.
*
* The buffer used to hold the transcription is statically
* allocated.
*/
const char * ( * ntoa ) ( const void * ll_addr );
/** Link-layer protocol
*
* This is an ARPHRD_XXX constant, in network byte order.
*/
uint16_t ll_proto;
/** Link-layer address length */
uint8_t ll_addr_len;
/** Link-layer broadcast address */
const uint8_t *ll_broadcast;
};
/**
* A network device
*
* This structure represents a piece of networking hardware. It has
* properties such as a link-layer address and methods for
* transmitting and receiving raw packets.
*
* Note that this structure must represent a generic network device,
* not just an Ethernet device.
*/
struct net_device {
/** List of network devices */
struct list_head list;
/** Transmit packet
*
* @v netdev Network device
* @v pkb Packet buffer
* @ret rc Return status code
*
* This method should cause the hardware to initiate
* transmission of the packet buffer.
*
* Ownership of the packet buffer is transferred to the @c
* net_device, which must eventually call free_pkb() to
* release the buffer.
*/
int ( * transmit ) ( struct net_device *netdev, struct pk_buff *pkb );
/** Poll for received packet
*
* @v netdev Network device
*
* This method should cause the hardware to check for received
* packets. Any received packets should be delivered via
* netdev_rx().
*/
void ( * poll ) ( struct net_device *netdev );
/** Link-layer protocol */
struct ll_protocol *ll_protocol;
/** Link-layer address
*
* For Ethernet, this is the MAC address.
*/
uint8_t ll_addr[MAX_LL_ADDR_LEN];
/** Received packet queue */
struct list_head rx_queue;
/** Driver private data */
void *priv;
};
/**
* Register a link-layer protocol
*
* @v protocol Link-layer protocol
*/
#define LL_PROTOCOL( protocol ) \
struct ll_protocol protocol __table ( ll_protocols, 01 )
/**
* Register a network-layer protocol
*
* @v protocol Network-layer protocol
*/
#define NET_PROTOCOL( protocol ) \
struct net_protocol protocol __table ( net_protocols, 01 )
/**
* Get network device name
*
* @v netdev Network device
* @ret name Network device name
*
* The name will be the device's link-layer address.
*/
static inline const char * netdev_name ( struct net_device *netdev ) {
return netdev->ll_protocol->ntoa ( netdev->ll_addr );
}
extern int netdev_tx ( struct net_device *netdev, struct pk_buff *pkb );
extern void netdev_rx ( struct net_device *netdev, struct pk_buff *pkb );
extern int net_tx ( struct pk_buff *pkb, struct net_device *netdev,
struct net_protocol *net_protocol, const void *ll_dest );
extern int net_rx ( struct pk_buff *pkb, struct net_device *netdev,
uint16_t net_proto, const void *ll_source );
extern int netdev_poll ( struct net_device *netdev );
extern struct pk_buff * netdev_rx_dequeue ( struct net_device *netdev );
extern struct net_device * alloc_netdev ( size_t priv_size );
extern int register_netdev ( struct net_device *netdev );
extern void unregister_netdev ( struct net_device *netdev );
extern void free_netdev ( struct net_device *netdev );
extern struct net_device * next_netdev ( void );
#endif /* _GPXE_NETDEVICE_H */
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