Ethduino/net.cpp

/*! \file net.c \brief Network support library. */
//*****************************************************************************
//
// File Name	: 'net.c'
// Title		: Network support library
// Author		: Pascal Stang
// Created		: 8/30/2004
// Revised		: 7/3/2005
// Version		: 0.1
// Target MCU	: Atmel AVR series
// Editor Tabs	: 4
//
//*****************************************************************************

#include <inttypes.h>
#include "HardwareSerial.h"

#include <avr/pgmspace.h>
#include "programStrings.h"

#include "net.h"

uint16_t htons(uint16_t val)
{
	return (val<<8) | (val>>8);
}

uint32_t htonl(uint32_t val)
{
	return (htons(val>>16) | (uint32_t)htons(val&0x0000FFFF)<<16);
}

uint16_t generateChecksum(uint16_t sum, netIpHeader *data, uint16_t len)
{
	uint16_t t;

	uint32_t *dataptr;
	uint32_t *last_byte;

#ifdef NET_CHECKSUM_DEBUG
	SPrint("Length for chksum func: ");
	Serial.println((long int)len, HEX);
#endif
	
	dataptr		= (uint32_t *) data;
	last_byte	= (uint32_t *) data + len - 1;

	while(dataptr < last_byte) {	// At least two more bytes
		t = (dataptr[0] << 8) + dataptr[1];
		sum += t;
		if(sum < t) {
			sum++;		// carry
		}
		dataptr += 2;
	}

	if(dataptr == last_byte) {
		t = (dataptr[0] << 8) + 0;
		sum += t;
		if(sum < t) {
			sum++;		// carry
		}
	}

	// Return sum in host byte order.
	return sum;
}

uint16_t ipChecksum(netIpHeader *data, uint16_t len)
{
	return htons(generateChecksum(0, data, len));
}

uint16_t netChecksum(netIpHeader *data, uint16_t len)
{
	uint16_t sum;
	sum = generateChecksum(0, &data[len], len);
	return (sum == 0) ? 0xffff : htons(sum);
}

void netPrintEthAddr(struct netEthAddr* ethaddr)
{
	Serial.print(ethaddr->addr[0], HEX);
	Serial.print(':');
	Serial.print(ethaddr->addr[1], HEX);
	Serial.print(':');
	Serial.print(ethaddr->addr[2], HEX);
	Serial.print(':');
	Serial.print(ethaddr->addr[3], HEX);
	Serial.print(':');
	Serial.print(ethaddr->addr[4], HEX);
	Serial.print(':');
	Serial.print(ethaddr->addr[5], HEX);
}

void netPrintIPAddr(uint32_t ipaddr)
{
	Serial.print(((unsigned char*)&ipaddr)[3], DEC);
	SPrint(".");
	Serial.print(((unsigned char*)&ipaddr)[2], DEC);
	SPrint(".");
	Serial.print(((unsigned char*)&ipaddr)[1], DEC);
	SPrint(".");
	Serial.print(((unsigned char*)&ipaddr)[0], DEC);
}

/*
void netPrintEthHeader(struct netEthHeader* eth_hdr)
{
	SPrint("Eth Packet Type: 0x");
	Serial.print(eth_hdr->type);

	SPrint(" SRC:");
	netPrintEthAddr(&eth_hdr->src);
	SPrint("->DST:");
	netPrintEthAddr(&eth_hdr->dest);
	Serial.println();
}

void netPrintIpHeader(struct netIpHeader* ipheader)
{
	SPrint("IP Header\r\n");
	SPrint_P(PSTR("Ver	   : %d\r\n", (ipheader->vhl)>>4);
	SPrint_P(PSTR("Length  : %d\r\n", htons(ipheader->len));
	if(ipheader->proto == IP_PROTO_ICMP)
		SPrint("Protocol: ICMP\r\n");
	else if(ipheader->proto == IP_PROTO_TCP)
		SPrint("Protocol: TCP\r\n");
	else if(ipheader->proto == IP_PROTO_UDP)
		SPrint("Protocol: UDP\r\n");
	else
		SPrint_P(PSTR("Protocol: %d\r\n", ipheader->proto);

	SPrint("SourceIP: "); netPrintIPAddr(htonl(ipheader->srcipaddr));	Serial.println();
	SPrint("Dest	 IP: "); netPrintIPAddr(htonl(ipheader->destipaddr));	Serial.println();
}

void netPrintTcpHeader(struct netTcpHeader* tcpheader)
{
	SPrint("TCP Header\r\n");
	SPrint_P(PSTR("Src Port: %d\r\n", htons(tcpheader->srcport));
	SPrint_P(PSTR("Dst Port: %d\r\n", htons(tcpheader->destport));
	SPrint("Seq Num : 0x"); Serial.printu32(htonl(tcpheader->seqno));	Serial.println();
	SPrint("Ack Num : 0x"); Serial.printu32(htonl(tcpheader->ackno));	Serial.println();
	SPrint("Flags   : ");
	if(tcpheader->flags & TCP_FLAGS_FIN)
		SPrint("FIN ");
	if(tcpheader->flags & TCP_FLAGS_SYN)
		SPrint("SYN ");
	if(tcpheader->flags & TCP_FLAGS_RST)
		SPrint("RST ");
	if(tcpheader->flags & TCP_FLAGS_PSH)
		SPrint("PSH ");
	if(tcpheader->flags & TCP_FLAGS_ACK)
		SPrint("ACK ");
	if(tcpheader->flags & TCP_FLAGS_URG)
		SPrint("URG ");
	Serial.println();
}
*/