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#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <malloc.h>
#include <byteswap.h>
#include <gpxe/in.h>
#include <gpxe/ip.h>
#include <gpxe/pkbuff.h>
#include <gpxe/tables.h>
#include <gpxe/netdevice.h>
#include <gpxe/tcpip_if.h>
/** @file
*
* Transport-network layer interface
*
* This file contains functions and utilities for the transport-network layer interface
*/
/** Registered network-layer protocols that support TCPIP */
static struct tcpip_net_protocol tcpip_net_protocols[0] __table_start ( tcpip_net_protocols );
static struct tcpip_net_protocol tcpip_net_protocols_end[0] __table_end ( tcpip_net_protocols );
struct tcpip_protocol;
/** Registered transport-layer protocols that support TCPIP */
static struct tcpip_protocol tcpip_protocols[0] __table_start ( tcpip_protocols );
static struct tcpip_protocol tcpip_protocols_end[0] __table_end ( tcpip_protocols );
/** Identify TCPIP network-layer protocol
*
* @v sa_family Network address family
* @ret tcpip Protocol supporting TCPIP, or NULL
*/
static struct tcpip_net_protocol * tcpip_find_protocol ( sa_family_t sa_family ) {
struct tcpip_net_protocol *tcpip_net;
for ( tcpip_net = tcpip_net_protocols;
tcpip_net < tcpip_net_protocols_end; ++tcpip_net ) {
if ( tcpip_net->sa_family == sa_family ) {
return tcpip_net;
}
}
return NULL;
}
/** Identify TCPIP transport-layer protocol
*
* @v trans_proto Transport-layer protocol number, IP_XXX
* @ret tcpip_protocol Transport-layer protocol, or NULL
*/
struct tcpip_protocol* find_tcpip_protocol ( uint8_t trans_proto ) {
struct tcpip_protocol *tcpip;
for ( tcpip = tcpip_protocols; tcpip <= tcpip_protocols_end;
++tcpip ) {
if ( tcpip->trans_proto == trans_proto ) {
return tcpip;
}
}
return NULL;
}
/** Process a received packet
*
* @v pkb Packet buffer
* @v trans_proto Transport-layer protocol number
* @v src Source network-layer address
* @v dest Destination network-layer address
*
* This function expects a transport-layer segment from the network-layer
*/
void trans_rx ( struct pk_buff *pkb, uint8_t trans_proto, struct in_addr *src,
struct in_addr *dest ) {
struct tcpip_protocol *tcpip;
/* Identify the transport layer protocol */
for ( tcpip = tcpip_protocols; tcpip <= tcpip_protocols_end; ++tcpip ) {
if ( tcpip->trans_proto == trans_proto ) {
DBG ( "Packet sent to %s module", tcpip->name );
tcpip->rx ( pkb, src, dest );
}
}
}
/** Transmit a transport-layer segment
*
* @v pkb Packet buffer
* @v trans_proto Transport-layer protocol
* @v sock Destination socket address
* @ret Status
*/
int trans_tx ( struct pk_buff *pkb, struct tcpip_protocol *tcpip,
struct sockaddr *sock ) {
/* Identify the network layer protocol and send it using xxx_tx() */
switch ( sock->sa_family ) {
case AF_INET: /* IPv4 network family */
return ipv4_tx ( pkb, tcpip, &sock->sin.sin_addr );
case AF_INET6: /* IPv6 network family */
return ipv6_tx ( pkb, tcpip, &sock->sin6.sin6_addr );
}
DBG ( "Network family %d not supported", sock->sa_family );
return -EAFNOSUPPORT;
}
/**
* Calculate internet checksum
*
* @v data Pointer to the data
* @v len Length of data to be checksummed
* @ret chksum 16 bit internet checksum
*
* This function calculates the internet checksum (refer RFC1071) for "len"
* bytes beginning at the location "data"
*/
uint16_t calc_chksum ( void *data, size_t len ) {
register long sum = 0;
uint16_t checksum;
unsigned short *temp;
while ( len > 1 ) {
temp = (unsigned short*) data++;
sum += *temp;
len -= 2;
}
if ( len > 0 ) {
sum += *(unsigned char *)data;
}
while ( sum >> 16 ) {
sum = ( sum & 0xffff ) + ( sum >> 16 );
}
checksum = ~sum;
return checksum;
}
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