void fnet_eth_output_ip4(fnet_netif_t *netif, fnet_ip4_addr_t dest_ip_addr, fnet_netbuf_t* nb)
{
    fnet_mac_addr_t destination_addr; /* 48-bit destination address */
    fnet_mac_addr_t * dest_ptr;
  
    /* Construct Ethernet header. Start with looking up deciding which
    * MAC address to use as a destination address. Broadcasts and
    * multicasts are special, all other addresses are looked up in the
    * ARP table. */
    if(fnet_ip_addr_is_broadcast (dest_ip_addr, netif))
    {
        fnet_memcpy (destination_addr, fnet_eth_broadcast, sizeof(fnet_mac_addr_t));
    }
    else if(FNET_IP4_ADDR_IS_MULTICAST(dest_ip_addr))
    {
        /* Hash IP multicast address to MAC address. */
        destination_addr[0] = 0x01;
        destination_addr[1] = 0x0;
        destination_addr[2] = 0x5e;
        destination_addr[3] = (unsigned char)(FNET_IP4_ADDR2(dest_ip_addr)& 0x7f);
        destination_addr[4] = (unsigned char)(FNET_IP4_ADDR3(dest_ip_addr));
        destination_addr[5] = (unsigned char)(FNET_IP4_ADDR4(dest_ip_addr));
        //TBD Use macro
    }
    else
    /* Unicast address. */
    {
        if((dest_ptr = fnet_arp_lookup(netif, dest_ip_addr))!=0)
        {
            fnet_memcpy (destination_addr, *dest_ptr, sizeof(fnet_mac_addr_t));
        }
        else
        {
            fnet_arp_resolve(netif, dest_ip_addr, nb);
            goto EXIT;
        }
    }

    /* Send Ethernet frame. */
    ((fnet_eth_if_t *)(netif->if_ptr))->output(netif, FNET_ETH_TYPE_IP4, destination_addr, nb);
EXIT:
    return;    
}
Example #2
0
void fnet_eth_output_ip4(fnet_netif_t *netif, fnet_ip4_addr_t dest_ip_addr, fnet_netbuf_t *nb)
{
    fnet_mac_addr_t destination_addr; /* 48-bit destination address */

    /* Construct Ethernet header. Start with looking up deciding which
    * MAC address to use as a destination address. Broadcasts and
    * multicasts are special, all other addresses are looked up in the
    * ARP table. */
    if(fnet_ip_addr_is_broadcast (dest_ip_addr, netif))
    {
        fnet_memcpy (destination_addr, fnet_eth_broadcast, sizeof(fnet_mac_addr_t));
    }
    else if(FNET_IP4_ADDR_IS_MULTICAST(dest_ip_addr))
    {
        /* Hash IP multicast address to MAC address. */
        destination_addr[0] = 0x01U;
        destination_addr[1] = 0x0U;
        destination_addr[2] = 0x5eU;
        destination_addr[3] = (fnet_uint8_t)(FNET_IP4_ADDR2(dest_ip_addr) & 0x7fU);
        destination_addr[4] = (fnet_uint8_t)(FNET_IP4_ADDR3(dest_ip_addr));
        destination_addr[5] = (fnet_uint8_t)(FNET_IP4_ADDR4(dest_ip_addr));
        /* TBD Use macro. */
    }
    else
        /* Unicast address. */
    {
        if(fnet_arp_get_mac( (fnet_netif_desc_t) netif, dest_ip_addr, destination_addr) == FNET_FALSE)
        {
            fnet_arp_resolve(netif, dest_ip_addr, nb);
            goto EXIT;
        }

    }

    /* Send Ethernet frame. */
    fnet_eth_output(netif, FNET_ETH_TYPE_IP4, destination_addr, nb);
EXIT:
    return;
}
Example #3
0
/************************************************************************
* NAME: fnet_icmp_input
*
* DESCRIPTION: ICMP input function.
*************************************************************************/
static void fnet_icmp_input(fnet_netif_t *netif, struct sockaddr *src_addr,  struct sockaddr *dest_addr, fnet_netbuf_t *nb, fnet_netbuf_t *ip4_nb)
{
    fnet_icmp_header_t      *hdr;
    fnet_prot_notify_t      prot_cmd;
    fnet_ip4_addr_t         src_ip;
    fnet_ip4_addr_t         dest_ip;
    
    fnet_netbuf_free_chain(ip4_nb); /* Not used.*/
    
    if((netif != 0) && (nb != 0) )
    {
        if(fnet_netbuf_pullup(&nb, sizeof(fnet_icmp_header_t)) == FNET_ERR) /* The header must reside in contiguous area of memory. */
        {
            goto DISCARD;
        }

        hdr = (fnet_icmp_header_t *)nb->data_ptr;

        src_ip = ((struct sockaddr_in*)(src_addr))->sin_addr.s_addr;
        dest_ip = ((struct sockaddr_in*)(dest_addr))->sin_addr.s_addr;

        if(
        #if FNET_CFG_CPU_ETH_HW_RX_PROTOCOL_CHECKSUM || FNET_CFG_CPU_ETH_HW_TX_PROTOCOL_CHECKSUM
            ((nb->flags & FNET_NETBUF_FLAG_HW_PROTOCOL_CHECKSUM) == 0) &&
        #endif
            (fnet_checksum(nb, nb->total_length))
            || (fnet_ip_addr_is_broadcast(src_ip, netif))
            || FNET_IP4_ADDR_IS_MULTICAST(src_ip))
        {
            goto DISCARD;
        }
        
        fnet_icmp_trace("RX", hdr); 
        
        switch(hdr->type)
        {
            /**************************
             * ICMP Request Processing
             **************************/
            case FNET_ICMP_ECHO:
                if((nb->total_length < sizeof(fnet_icmp_echo_header_t)) ||
                /* An ICMP Echo Request destined to an IP broadcast or IP
                * multicast address MAY be silently discarded.(RFC1122)*/
                (fnet_ip_addr_is_broadcast(dest_ip, netif)) || FNET_IP4_ADDR_IS_MULTICAST(dest_ip))
                {
                    goto DISCARD;
                }

                hdr->type = FNET_ICMP_ECHOREPLY;

                fnet_icmp_output(netif, dest_ip, src_ip, nb);
                break;
#if 0 /* Optional functionality.*/                
            /************************
             * Time Stamp Query 
             ************************/
            case FNET_ICMP_TSTAMP:
 
                /* The header must reside in contiguous area of memory. */
                if(fnet_netbuf_pullup(&nb, sizeof(fnet_icmp_timestamp_header_t)) == FNET_ERR)
                {
                    goto DISCARD;
                }

                hdr = nb->data_ptr;

                hdr->type = FNET_ICMP_TSTAMPREPLY;
                /* All times are in milliseconds since the stack timer start modulo 1 day. 
                * The high-order bit is set as the time value is recorded in nonstandard units. */
                ((fnet_icmp_timestamp_header_t *)hdr)->receive_timestamp
                    = fnet_htonl(((fnet_timer_ticks() * FNET_TIMER_PERIOD_MS) % (24 * 60 * 60 * 1000)) | (0x80000000));

                dest_ip = netif->ip4_addr.address;

                fnet_icmp_output(netif, dest_ip, src_ip, nb);
                break;
            /************************
             * Address Mask Query
             ************************/
            case FNET_ICMP_MASKREQ:
                /* The header must reside in contiguous area of memory*/
                if(fnet_netbuf_pullup(&nb, sizeof(fnet_icmp_mask_header_t)) == FNET_ERR) 
                {
                    goto DISCARD;
                }

                hdr = nb->data_ptr;

                hdr->type = FNET_ICMP_MASKREPLY;

                ((fnet_icmp_mask_header_t *)hdr)->mask = netif->ip4_addr.subnetmask;

                dest_ip = netif->ip4_addr.address;

                fnet_icmp_output(netif, dest_ip, src_ip, nb);
                break;
#endif                
            /**************************
             * ICMP Error Processing
             **************************/
            case FNET_ICMP_UNREACHABLE:
                switch(hdr->code)
                {
                    case FNET_ICMP_UNREACHABLE_NET:           /* net unreachable */
                    case FNET_ICMP_UNREACHABLE_NET_UNKNOWN:   /* unknown net */
                    case FNET_ICMP_UNREACHABLE_NET_PROHIB:    /* prohibited access */
                    case FNET_ICMP_UNREACHABLE_TOSNET:        /* bad tos for net */
                        prot_cmd = FNET_PROT_NOTIFY_UNREACH_NET;
                        break;

                    case FNET_ICMP_UNREACHABLE_HOST:          /* host unreachable */
                    case FNET_ICMP_UNREACHABLE_HOST_UNKNOWN:  /* unknown host */
                    case FNET_ICMP_UNREACHABLE_ISOLATED:      /* src host isolated */
                    case FNET_ICMP_UNREACHABLE_HOST_PROHIB:   /* ditto */
                    case FNET_ICMP_UNREACHABLE_TOSHOST:       /* bad tos for host */
                        prot_cmd = FNET_PROT_NOTIFY_UNREACH_HOST;
                        break;

                    case FNET_ICMP_UNREACHABLE_PROTOCOL:      /* protocol unreachable */
                        prot_cmd = FNET_PROT_NOTIFY_UNREACH_PROTOCOL;
                        break;

                    case FNET_ICMP_UNREACHABLE_PORT:          /* port unreachable */
                        prot_cmd = FNET_PROT_NOTIFY_UNREACH_PORT;
                        break;

                    case FNET_ICMP_UNREACHABLE_SRCFAIL:       /* source route failed */
                        prot_cmd = FNET_PROT_NOTIFY_UNREACH_SRCFAIL;
                        break;

                    case FNET_ICMP_UNREACHABLE_NEEDFRAG:      /* fragmentation needed and DF set*/
                        prot_cmd = FNET_PROT_NOTIFY_MSGSIZE;
                        break;

                    default:
                        goto DISCARD;
                }
                fnet_icmp_notify_protocol(prot_cmd, nb);  /* Protocol notification.*/
                break;
            case FNET_ICMP_TIMXCEED:
                switch(hdr->code)
                {
                    case FNET_ICMP_TIMXCEED_INTRANS:          /* time to live exceeded in transit (ttl==0)*/
                        prot_cmd = FNET_PROT_NOTIFY_TIMXCEED_INTRANS;
                        break;

                    case FNET_ICMP_TIMXCEED_REASS:            /* fragment reassembly time exceeded (ttl==0)*/
                        prot_cmd = FNET_PROT_NOTIFY_TIMXCEED_REASS;
                        break;

                    default:
                        goto DISCARD;
                }

                fnet_icmp_notify_protocol(prot_cmd, nb);  /* Protocol notification.*/
                break;
            case FNET_ICMP_PARAMPROB:                       /* Parameter Problem Message.*/
                if(hdr->code > 1u)
                {
                    goto DISCARD;
                }

                prot_cmd = FNET_PROT_NOTIFY_PARAMPROB;
                fnet_icmp_notify_protocol(prot_cmd, nb);  /* Protocol notification.*/
                break;
            case FNET_ICMP_SOURCEQUENCH:                    /* Source Quench Message; packet lost, slow down.*/
                if(hdr->code)
                {
                    goto DISCARD;
                }

                prot_cmd = FNET_PROT_NOTIFY_QUENCH;
                fnet_icmp_notify_protocol(prot_cmd, nb);  /* Protocol notification.*/
                break;
            /************************
             * Ignore others
             ************************/
            /*
            case FNET_ICMP_REDIRECT:
            case FNET_ICMP_ECHOREPLY:
            case FNET_ICMP_ROUTERADVERT:
            case FNET_ICMP_ROUTERSOLICIT:
            case FNET_ICMP_TSTAMPREPLY:
            case FNET_ICMP_IREQREPLY:
            case FNET_ICMP_MASKREPLY:*/
            default:
                goto DISCARD;
                
        }/* switch(hdr->type) */
    }
    else
    {
DISCARD:
        fnet_netbuf_free_chain(nb);
    }
}
Example #4
0
/************************************************************************
* NAME: fnet_icmp_error
*
* DESCRIPTION: Sends ICMP error message.
*************************************************************************/
void fnet_icmp_error( fnet_netif_t *netif, fnet_uint8_t type, fnet_uint8_t code, fnet_netbuf_t *nb )
{
    fnet_ip_header_t        *ipheader;
    fnet_netbuf_t           *nb_header;
    fnet_icmp_err_header_t  *icmpheader;
    fnet_ip4_addr_t          source_addr;
    fnet_ip4_addr_t          destination_addr;
    

    if(nb)
    {
        ipheader = (fnet_ip_header_t *)nb->data_ptr;
        
        source_addr = ipheader->source_addr;
        destination_addr = ipheader->desination_addr;

        /* Do not send error if not the first fragment of message (RFC1122)*/
        if((FNET_IP_HEADER_GET_OFFSET(ipheader) != 0u) ||
            /* Do not send error on ICMP error messages*/
            ((ipheader->protocol == FNET_IP_PROTOCOL_ICMP)
              && (!FNET_ICMP_IS_QUERY_TYPE(((fnet_icmp_header_t *)((fnet_uint8_t *)(nb->data_ptr) + (FNET_IP_HEADER_GET_HEADER_LENGTH(ipheader) << 2)))->type))) 
            /* Do not send error on a datagram whose source address does not define a single
             * host -- e.g., a zero address, a loopback address, a
             * broadcast address, a multicast address, or a Class E
             * address.*/
            || (fnet_ip_addr_is_broadcast(source_addr, netif))
            || FNET_IP4_ADDR_IS_MULTICAST(source_addr) 
            || FNET_IP4_CLASS_E(source_addr)
            /* Do not send error on a datagram destined to an IP broadcast or IP multicast address*/
            || (fnet_ip_addr_is_broadcast(destination_addr, netif))
            || FNET_IP4_ADDR_IS_MULTICAST(destination_addr)
             /* Do not send error on datagram sent as a link-layer broadcast or multicast.*/
            ||((nb->flags & FNET_NETBUF_FLAG_BROADCAST) != 0u) || ((nb->flags & FNET_NETBUF_FLAG_MULTICAST) != 0u)
        )
        {
            goto FREE_NB;
        }

        /* Construct ICMP error header*/
        if((nb_header = fnet_netbuf_new((sizeof(fnet_icmp_err_header_t) - sizeof(fnet_ip_header_t)), FNET_FALSE)) == 0)
        {
            goto FREE_NB;
        }

        icmpheader = (fnet_icmp_err_header_t *)nb_header->data_ptr;
        icmpheader->fields.unused = 0u;

        if(type == FNET_ICMP_PARAMPROB)
        {
            icmpheader->fields.ptr = fnet_htons((fnet_uint16_t)code);
            code = 0u;
        }
        else if((type == FNET_ICMP_PARAMPROB) && (code == FNET_ICMP_UNREACHABLE_NEEDFRAG) && netif)
        {    
            icmpheader->fields.mtu = fnet_htons((fnet_uint16_t)netif->mtu);
        }
        else
        {}

        icmpheader->header.type = type;
        icmpheader->header.code = code;

        if((fnet_size_t)((FNET_IP_HEADER_GET_HEADER_LENGTH(ipheader) << 2) + 8u) < nb->total_length)
        {
            fnet_netbuf_trim(&nb, (fnet_int32_t)((fnet_size_t)((FNET_IP_HEADER_GET_HEADER_LENGTH(ipheader) << 2) + 8u) - nb->total_length));
        }

        nb = fnet_netbuf_concat(nb_header, nb);

        fnet_icmp_output(netif, destination_addr, source_addr, nb);

        return;

FREE_NB:
        fnet_netbuf_free_chain(nb);
    }
}