/*
 ******************************************************************************
 *                     INTERPEAK SOURCE FILE
 *
 *   Document no: @(#) $Name: VXWORKS_ITER40_2019102207 $ $RCSfile: ipmipmn_icmp.c,v $ $Revision: 1.6 $
 *   $Source: /home/interpeak/CVSRoot/ipmipmn/src/ipmipmn_icmp.c,v $
 *   $Author: jhorteli $
 *   $State: Exp $ $Locker:  $
 *
 *   INTERPEAK_COPYRIGHT_STRING
 *     Design and implementation by Joel Hortelius <joel.hortelis@interpeak.se>
 ******************************************************************************
 */


/*
 ****************************************************************************
 * 1                    DESCRIPTION
 ****************************************************************************
 */

/*
 ****************************************************************************
 * 2                    CONFIGURATION
 ****************************************************************************
 */

#include "ipmipmn_config.h"

/*
 ****************************************************************************
 * 3                    INCLUDE FILES
 ****************************************************************************
 */

#define IPCOM_USE_CLIB_PROTO
#include <ipcom_clib.h>
#include <ipcom_err.h>
#include <ipcom_os.h>
#include <ipcom_sock.h>
#include <ipcom_inet.h>
#include <ipcom_syslog.h>
#include <ipcom_ipd.h>
#include <ipcom_sock.h>
#include <ipcom_sock2.h>
#include <ipcom_list.h>
#include <ipcom_hash.h>

#include <ipmip.h>
#include <private/ipmip_sysvar.h>

#include <ipmip4.h>
#include <private/ipmip4_lla.h>
#include <private/ipmip4_util.h>
#include <private/ipmip4_sysext.h>
#include <private/ipmip4_context.h>
#include <private/ipmip4_pkt.h>

#include <private/ipmipmn_api.h>
#include "ipmipmn_h.h"
#include "ipmipmn_if.h"
#include "ipmipmn_pktbuf.h"
#include "ipmipmn_icmp.h"

/*
 ****************************************************************************
 * 4                    DEFINES
 ****************************************************************************
 */

/*
 ****************************************************************************
 * 5                    TYPES
 ****************************************************************************
 */

/*
 ****************************************************************************
 * 6                    EXTERN PROTOTYPES
 ****************************************************************************
 */

/*
 ****************************************************************************
 * 7                    LOCAL PROTOTYPES
 ****************************************************************************
 */

/*
 ****************************************************************************
 * 8                    DATA
 ****************************************************************************
 */

/*
 ****************************************************************************
 * 9                    STATIC FUNCTIONS
 ****************************************************************************
 */

/*
 *===========================================================================
 *                    ipmipmn_icmp_input
 *===========================================================================
 * Description:
 * Parameters:
 * Returns:
 *
 */
IP_STATIC void
ipmipmn_icmp_input(Ipmipmn_context_t         *data,
                   Ipmip_proc_t              *proc,
                   Ipmipmn_pktbuf_t          *pbuf)
{
    Ipmip4_icmp_advert_t        *pkt;
    int                         ret;
    Ipmip4_icmp_ext_advert_t    *extadv;

    /* Too short packet */
    if (IPMIP_BUFFER_SIZE(&pbuf->api.ipmip4.ipmip.packet) < sizeof(Ipmip4_icmp_advert_t))
    {
        IPCOM_LOG2(WARNING, "ADV ipcom_recvmsg() failed from '%s', short packet [length = %d]",
                   ipmip_ntop_sa(proc, pbuf->api.ipmip4.ipmip.srcinfo.src),
                   IPMIP_BUFFER_SIZE(&pbuf->api.ipmip4.ipmip.packet));
        return;
    }

    /* We only listen on ICMP agent advertisements */
    pkt     = IPMIP_BUFFER_PTR(&pbuf->api.ipmip4.ipmip.packet);

    /* Sanity */
    if (pkt->adv_num_addrs > 0 && pkt->adv_addr_entry_size < 2)
    {
        IPCOM_LOG2(WARNING, "ADV ipcom_recvmsg() failed from '%s', short addr/pref [length = %d]",
                   ipmip_ntop_sa(proc, pbuf->api.ipmip4.ipmip.srcinfo.src),
                   pkt->adv_addr_entry_size);
        return;
    }

    ret         = sizeof(Ipmip4_icmp_advert_t) + (pkt->adv_num_addrs * pkt->adv_addr_entry_size * 4);

    /* Too short packet */
    if (IPMIP_BUFFER_SIZE(&pbuf->api.ipmip4.ipmip.packet) < (unsigned)ret)
    {
        IPCOM_LOG2(WARNING, "ADV ipcom_recvmsg() failed from '%s', short packet [length = %d]",
                   ipmip_ntop_sa(proc, pbuf->api.ipmip4.ipmip.srcinfo.src),
                   IPMIP_BUFFER_SIZE(&pbuf->api.ipmip4.ipmip.packet));
        return;
    }

    /* Parse the message block */
    ret = ipmip4_msgext_icmp_parse(proc,
                                   pbuf->api.iff.pub->ipmip.ifname,
                                   pbuf->api.ipmip4.ipmip.srcinfo.src->sin.sin_addr.s_addr,
                                   &pbuf->api.ipmip4.ext.icmp,
                                   ipmip_buffer_offset(&pbuf->api.ipmip4.ipmip.packet, ret),
                                   IPMIP_BUFFER_SIZE(&pbuf->api.ipmip4.ipmip.packet) - ret);

    /* Did the parse succeed? */
    if (ret != IPMIP4_REG_EXT_SUCCESS)
        return;

    /* Is it a mobility advertisement? */
    if (pbuf->api.ipmip4.ext.icmp.agent == IP_NULL)
        return;

    /* Retrieve the mobility advertisement */
    extadv = (Ipmip4_icmp_ext_advert_t *) pbuf->api.ipmip4.ext.icmp.agent;

    /* Extract the advertised lifetime and flags */
    pbuf->api.advinfo.lifetime = IP_GET_NTOHS(&extadv->reg_lifetime);
    pbuf->api.advinfo.flags    = IP_GET_NTOHS(&extadv->flags);
    pbuf->api.advinfo.adv_seq  = IP_GET_NTOHS(&extadv->seq);

    /*********** FOREIGN AGENT ADVERTISEMENT ***********/
    if (IP_BIT_ISTRUE(pbuf->api.advinfo.flags, IPMIP4_ICMP_ADVEXT_FLAG_FOREIGN_AGENT))
    {
        /* An FA agent adv is required to include at least one c/o-address */
        if (IPMIP4_MSGEXT_SHDR_EXT_SIZE(extadv) < 10)
        {
            IPCOM_LOG1(WARNING, "missing c/o address from '%s' FA",
                       ipmip_ntop_sa(proc, pbuf->api.ipmip4.ipmip.srcinfo.src));
            return;
        }

        pbuf->api.advinfo.coa = IP_GET_32ON8(&extadv->coa[0]);

        IPCOM_LOG4(DEBUG, "received FA %sRtAdv #%d from '%s' [c/o=%s]",
                   pbuf->api.ipmip4.ext.icmp.lla.found > 0? "Pr" : "",
                   pbuf->api.advinfo.adv_seq,
                   ipmip_ntop_sa(proc, pbuf->api.ipmip4.ipmip.srcinfo.src),
                   ipmip_ntop_inet(proc, pbuf->api.advinfo.coa));

        /* Lookup and init FA */
        ipmipmn_if_fa_adv(data, proc, pbuf);
    }
    /*********** HOME AGENT ADVERTISEMENT ***********/
    else if (IP_BIT_ISTRUE(pbuf->api.advinfo.flags, IPMIP4_ICMP_ADVEXT_FLAG_HOME_AGENT))
    {
        IPCOM_LOG2(DEBUG, "received HA RtAdv #%d from '%s'",
                   pbuf->api.advinfo.adv_seq,
                   ipmip_ntop_sa(proc, pbuf->api.ipmip4.ipmip.srcinfo.src));

        /* Lookup and init FA */
        ipmipmn_if_ha_adv(data, proc, pbuf);

    }

    return;
}


/*
 ****************************************************************************
 * 10                   GLOBAL FUNCTIONS
 ****************************************************************************
 */

/*
 *===========================================================================
 *                    ipmipmn_icmp_recv
 *===========================================================================
 * Description:   Handles incoming advertisements or solicitations
 * Parameters:    data          - Context
 *                proc          - Current process.
 *                pbuf          - Packet buffer
 * Returns:       
 *
 */
IP_GLOBAL void 
ipmipmn_icmp_recv(struct Ipmipmn_context        *data,
                  struct Ipmip_proc             *proc,                 
                  Ipmipmn_pktbuf_t               *pbuf)
{
    if (pbuf->api.ipmip4.ipmip.srcinfo.lladdr != IP_NULL)
    {
        Ipcom_icmp_header       *icmph   = IPMIP_BUFFER_PTR(&pbuf->api.ipmip4.ipmip.packet);

        /* Truncated packet? */
        if (IPMIP_BUFFER_SIZE(&pbuf->api.ipmip4.ipmip.packet) < IPCOM_ICMP_HEADER_LENGTH)
            goto done_out;

        if ((pbuf->api.iff.priv = ipmipmn_if_findbyindex(data, proc, pbuf->api.ipmip4.ipmip.srcinfo.dst->ifindex)) == IP_NULL)
            goto done_out;

        switch (icmph->type)
        {
            case IPMIP4_ICMP_AGENT_ADVERTISEMENT:
                ipmipmn_icmp_input(data, proc, pbuf);
                break;
        }
    }
    else
    {
            /* Failure */
        IPCOM_LOG0(ERR,
                   "NO MAC");
    }

done_out:
    /* Free the packet buffer */
    ipmip_pktbuf_release(&data->api.ipmip4.ipmip, proc, &pbuf->api.ipmip4.ipmip);
}

/*
 ****************************************************************************
 * 11                   PUBLIC FUNCTIONS
 ****************************************************************************
 */

/*
 ****************************************************************************
 *                      END OF FILE
 ****************************************************************************
 */