#ifndef _IPXE_TCPIP_H
#define _IPXE_TCPIP_H
/** @file
*
* Transport-network layer interface
*
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <stdint.h>
#include <ipxe/socket.h>
#include <ipxe/in.h>
#include <ipxe/tables.h>
extern uint16_t generic_tcpip_continue_chksum ( uint16_t partial,
const void *data, size_t len );
#include <bits/tcpip.h>
struct io_buffer;
struct net_device;
struct ip_statistics;
/** Positive zero checksum value */
#define TCPIP_POSITIVE_ZERO_CSUM 0x0000
/** Negative zero checksum value */
#define TCPIP_NEGATIVE_ZERO_CSUM 0xffff
/** Empty checksum value
*
* All of our TCP/IP checksum algorithms will return only the positive
* representation of zero (0x0000) for a zero checksum over non-zero
* input data. This property arises since the end-around carry used
* to mimic one's complement addition using unsigned arithmetic
* prevents the running total from ever returning to 0x0000. The
* running total will therefore use only the negative representation
* of zero (0xffff). Since the return value is the one's complement
* negation of the running total (calculated by simply bit-inverting
* the running total), the return value will therefore use only the
* positive representation of zero (0x0000).
*
* It is a very common misconception (found in many places such as
* RFC1624) that this is a property guaranteed by the underlying
* mathematics. It is not; the choice of which zero representation is
* used is merely an artifact of the software implementation of the
* checksum algorithm.
*
* For consistency, we choose to use the positive representation of
* zero (0x0000) for the checksum of a zero-length block of data.
* This ensures that all of our TCP/IP checksum algorithms will return
* only the positive representation of zero (0x0000) for a zero
* checksum (regardless of the input data).
*/
#define TCPIP_EMPTY_CSUM TCPIP_POSITIVE_ZERO_CSUM
/** TCP/IP address flags */
enum tcpip_st_flags {
/** Bind to a privileged port (less than 1024)
*
* This value is chosen as 1024 to optimise the calculations
* in tcpip_bind().
*/
TCPIP_BIND_PRIVILEGED = 0x0400,
};
/**
* TCP/IP socket address
*
* This contains the fields common to socket addresses for all TCP/IP
* address families.
*/
struct sockaddr_tcpip {
/** Socket address family (part of struct @c sockaddr) */
sa_family_t st_family;
/** Flags */
uint16_t st_flags;
/** TCP/IP port */
uint16_t st_port;
/** Scope ID
*
* For link-local or multicast addresses, this is the network
* device index.
*/
uint16_t st_scope_id;
/** Padding
*
* This ensures that a struct @c sockaddr_tcpip is large
* enough to hold a socket address for any TCP/IP address
* family.
*/
char pad[ sizeof ( struct sockaddr ) -
( sizeof ( sa_family_t ) /* st_family */ +
sizeof ( uint16_t ) /* st_flags */ +
sizeof ( uint16_t ) /* st_port */ +
sizeof ( uint16_t ) /* st_scope_id */ ) ];
} __attribute__ (( packed, may_alias ));
/**
* A transport-layer protocol of the TCP/IP stack (eg. UDP, TCP, etc)
*/
struct tcpip_protocol {
/** Protocol name */
const char *name;
/**
* Process received packet
*
* @v iobuf I/O buffer
* @v netdev Network device
* @v st_src Partially-filled source address
* @v st_dest Partially-filled destination address
* @v pshdr_csum Pseudo-header checksum
* @ret rc Return status code
*
* This method takes ownership of the I/O buffer.
*/
int ( * rx ) ( struct io_buffer *iobuf, struct net_device *netdev,
struct sockaddr_tcpip *st_src,
struct sockaddr_tcpip *st_dest, uint16_t pshdr_csum );
/** Preferred zero checksum value
*
* The checksum is a one's complement value: zero may be
* represented by either positive zero (0x0000) or negative
* zero (0xffff).
*/
uint16_t zero_csum;
/**
* Transport-layer protocol number
*
* This is a constant of the type IP_XXX
*/
uint8_t tcpip_proto;
};
/**
* A network-layer protocol of the TCP/IP stack (eg. IPV4, IPv6, etc)
*/
struct tcpip_net_protocol {
/** Protocol name */
const char *name;
/** Network address family */
sa_family_t sa_family;
/** Fixed header length */
size_t header_len;
/** Network-layer protocol */
struct net_protocol *net_protocol;
/**
* Transmit packet
*
* @v iobuf I/O buffer
* @v tcpip_protocol Transport-layer protocol
* @v st_src Source address, or NULL to use default
* @v st_dest Destination address
* @v netdev Network device (or NULL to route automatically)
* @v trans_csum Transport-layer checksum to complete, or NULL
* @ret rc Return status code
*
* This function takes ownership of the I/O buffer.
*/
int ( * tx ) ( struct io_buffer *iobuf,
struct tcpip_protocol *tcpip_protocol,
struct sockaddr_tcpip *st_src,
struct sockaddr_tcpip *st_dest,
struct net_device *netdev,
uint16_t *trans_csum );
/**
* Determine transmitting network device
*
* @v st_dest Destination address
* @ret netdev Network device, or NULL
*/
struct net_device * ( * netdev ) ( struct sockaddr_tcpip *dest );
};
/** TCP/IP transport-layer protocol table */
#define TCPIP_PROTOCOLS __table ( struct tcpip_protocol, "tcpip_protocols" )
/** Declare a TCP/IP transport-layer protocol */
#define __tcpip_protocol __table_entry ( TCPIP_PROTOCOLS, 01 )
/** TCP/IP network-layer protocol table */
#define TCPIP_NET_PROTOCOLS \
__table ( struct tcpip_net_protocol, "tcpip_net_protocols" )
/** Declare a TCP/IP network-layer protocol */
#define __tcpip_net_protocol __table_entry ( TCPIP_NET_PROTOCOLS, 01 )
extern int tcpip_rx ( struct io_buffer *iobuf, struct net_device *netdev,
uint8_t tcpip_proto, struct sockaddr_tcpip *st_src,
struct sockaddr_tcpip *st_dest, uint16_t pshdr_csum,
struct ip_statistics *stats );
extern int tcpip_tx ( struct io_buffer *iobuf, struct tcpip_protocol *tcpip,
struct sockaddr_tcpip *st_src,
struct sockaddr_tcpip *st_dest,
struct net_device *netdev,
uint16_t *trans_csum );
extern struct tcpip_net_protocol * tcpip_net_protocol ( sa_family_t sa_family );
extern struct net_device * tcpip_netdev ( struct sockaddr_tcpip *st_dest );
extern size_t tcpip_mtu ( struct sockaddr_tcpip *st_dest );
extern uint16_t tcpip_chksum ( const void *data, size_t len );
extern int tcpip_bind ( struct sockaddr_tcpip *st_local,
int ( * available ) ( int port ) );
#endif /* _IPXE_TCPIP_H */
