ip.c

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/*! \file ip.c \brief IP (Internet Protocol) Library. */
//*****************************************************************************
//
// File Name    : 'ip.c'
// Title        : IP (Internet Protocol) 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 "global.h"
#include "rprintf.h"

#include "net.h"
#include "nic.h"
#include "arp.h"
#include "ip.h"

struct ipConfig IpMyConfig; ///< Local IP address/config structure


void ipSetConfig(uint32_t myIp, uint32_t netmask, uint32_t gatewayIp)
{
    struct netEthAddr ethaddr;

    // set local addressing
    IpMyConfig.ip = myIp;
    IpMyConfig.netmask = netmask;
    IpMyConfig.gateway = gatewayIp;

    // set ARP association
    nicGetMacAddress(ethaddr.addr);
    arpSetAddress(&ethaddr, myIp);
}

struct ipConfig* ipGetConfig(void)
{
    return &IpMyConfig;
}

// deprecated
/*
uint32_t ipGetMyAddress(void)
{
    return IpMyConfig.ip;
}
*/

void ipSend(uint32_t dstIp, uint8_t protocol, uint16_t len, uint8_t* data)
{
    // make pointer to ethernet/IP header
    struct netEthIpHeader* ethIpHeader;

    // move data pointer to make room for headers
    data -= ETH_HEADER_LEN+IP_HEADER_LEN;
    ethIpHeader = (struct netEthIpHeader*)data;

//  debugPrintHexTable(len+ETH_HEADER_LEN+IP_HEADER_LEN, data);

    // adjust length to add IP header
    len += IP_HEADER_LEN;

    // fill IP header
    ethIpHeader->ip.destipaddr = HTONL(dstIp);
    ethIpHeader->ip.srcipaddr = HTONL(IpMyConfig.ip);
    ethIpHeader->ip.proto = protocol;
    ethIpHeader->ip.len = htons(len);
    ethIpHeader->ip.vhl = 0x45;
    ethIpHeader->ip.tos = 0;
    ethIpHeader->ip.ipid = 0;
    ethIpHeader->ip.ipoffset = 0;
    ethIpHeader->ip.ttl = IP_TIME_TO_LIVE;
    ethIpHeader->ip.ipchksum = 0;

    // calculate and apply IP checksum
    // DO THIS ONLY AFTER ALL CHANGES HAVE BEEN MADE TO IP HEADER
    ethIpHeader->ip.ipchksum = netChecksum(&ethIpHeader->ip, IP_HEADER_LEN);

    // add ethernet routing
    // check if we need to send to gateway
    if( (dstIp & IpMyConfig.netmask) == (IpMyConfig.ip & IpMyConfig.netmask) )
    {
        arpIpOut(ethIpHeader,0);                    // local send
        //rprintf("Sending IP packet on local net\r\n");
    }
    else
    {
        arpIpOut(ethIpHeader,IpMyConfig.gateway);   // gateway send
        //rprintf("Sending IP packet to gateway\r\n");
    }

    // adjust length to add ethernet header
    len += ETH_HEADER_LEN;

    // debug
    //debugPrintHexTable(ETH_HEADER_LEN, &data[0]);
    //debugPrintHexTable(len-ETH_HEADER_LEN, &data[ETH_HEADER_LEN]);

    // send it
    nicSend(len, data);
}

void udpSend(uint32_t dstIp, uint16_t dstPort, uint16_t len, uint8_t* data)
{
    // make pointer to UDP header
    struct netUdpHeader* udpHeader;
    // move data pointer to make room for UDP header
    data -= UDP_HEADER_LEN;
    udpHeader = (struct netUdpHeader*)data;
    // adjust length to add UDP header
    len += UDP_HEADER_LEN;
    // fill UDP header
    udpHeader->destport = HTONS(dstPort);
    udpHeader->srcport  = HTONS(dstPort);
    udpHeader->udplen = htons(len);
    udpHeader->udpchksum = 0;

//  debugPrintHexTable(UDP_HEADER_LEN, (uint8_t*)udpPacket);

    ipSend(dstIp, IP_PROTO_UDP, len, (uint8_t*)udpHeader);
}

void ipPrintConfig(struct ipConfig* config)
{
    rprintfProgStrM("IP Addr : "); netPrintIPAddr(config->ip);      rprintfCRLF();
    rprintfProgStrM("Netmask : "); netPrintIPAddr(config->netmask); rprintfCRLF();
    rprintfProgStrM("Gateway : "); netPrintIPAddr(config->gateway); rprintfCRLF();
}

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