/*
 ******************************************************************************
 *                     INTERPEAK SOURCE FILE
 *
 *   Document no: @(#) $Name: VXWORKS_ITER40_2019102207 $ $RCSfile: ipmip6_nd_proxy.c,v $ $Revision: 1.15 $
 *   $Source: /home/interpeak/CVSRoot/ipmip6/src/ipmip6_nd_proxy.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 "ipmip6_config.h"

/*
 ****************************************************************************
 * 3                    INCLUDE FILES
 ****************************************************************************
 */
#define IPCOM_USE_CLIB_PROTO
#include <ipcom_clib.h>
#include <ipcom_os.h>
#include <ipcom_list.h>
#include <ipcom_sock.h>
#include <ipcom_sock6.h>
#include <ipcom_inet.h>
#include <ipcom_err.h>
#include <ipcom_syslog.h>
#include <ipcom_netif.h>

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

#include "ipmip6_h.h"
#include <private/ipmip6_context.h>
#include <private/ipmip6_nd_proxy.h>
#include <private/ipmip6_nd_nud.h>
#include <private/ipmip6_if.h>
#include <private/ipmip6_icmp.h>
#include <private/ipmip6_icmp_pkt.h>
#include <private/ipmip6_util.h>
/*
 ****************************************************************************
 * 4                    DEFINES
 ****************************************************************************
 */

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

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

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

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

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


/*
 *===========================================================================
 *                    ipmip6_nd_proxy_unsolicited_timeout
 *===========================================================================
 * Description: Send a new unsolicited message
 * Parameters:  cookie  - The proxy structure.
 * Returns:     IP_TRUE if we're not done yet, IP_FALSE otherwise
 *
 */
IP_STATIC int
ipmip6_nd_proxy_unsolicited_timeout_iflocked(int                       event,
                                             Ipmip6_context_t          *ctx,
                                             Ipmip_proc_t              *proc,
                                             Ipmip6_nd_proxy_t         *proxy,
                                             void                      *unused)
{
    IPMIP_UNUSED_PARAMETER(unused);
    if (event == IPMIP_TIMER_EVENT_RUN)
    {
        /* */
        ++proxy->sent;

        /* Send an unsolicited neighbor advertisement */
        ipmip6_icmp_neighbor_advertisement(ctx, proc, proxy, IP_NULL, IP_TRUE);

        /**/
        return proxy->sent < 3? IPMIP_TIMER_RET_REINSERT : IPMIP_TIMER_RET_DONE;
    }

    return IPMIP_TIMER_RET_DONE;
}

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

 
/*
 *===========================================================================
 *                    ipmip6_nd_proxy_start_solicited_iflocked
 *===========================================================================
 * Description: Start passive proxying for a given address
 * Parameters:  proxy   - The proxy object
 * Returns:     
 *
 */
IP_GLOBAL void
ipmip6_nd_proxy_start_solicited_iflocked(Ipmip6_context_t        *ctx,
                                         Ipmip_proc_t            *proc,
                                         struct Ipmip6_if        *ife,
                                         Ipmip6_nd_proxy_t       *proxy)
{
    /* Stop any previous proxy registrations */
    ipmip6_nd_proxy_stop_iflocked(ctx, proc, proxy);

    /* Set solicited mode */
    proxy->ifp   = ife;

    /* Add to the list */
    ipcom_list_insert_first(&proxy->ifp->iff_nd_proxy, &proxy->next);

    /* Join the solicitated address */
    ipmip6_icmp_mc_solicitated_address(ctx,
                                       proc,
                                       IP_TRUE,
                                       proxy->ifp,
                                       proxy->addr);
}


/*
 *===========================================================================
 *                    ipmip6_nd_proxy_start_unsolicited_iflocked
 *===========================================================================
 * Description: Start unsolicited neighbor advertisements
 * Parameters:  proxy   - The proxy object
 * Returns:     
 *
 */
IP_GLOBAL void
ipmip6_nd_proxy_start_unsolicited_iflocked(Ipmip6_context_t      *ctx,
                                           Ipmip_proc_t          *proc,
                                           struct Ipmip6_if      *ife,
                                           Ipmip6_nd_proxy_t     *proxy)
{
    /* Stop any previous proxy registrations */
    ipmip6_nd_proxy_stop_iflocked(ctx, proc, proxy);

    /* Set unsolicted mode */
    proxy->ifp   = ife;

    /* Add to the list */
    ipcom_list_insert_first(&proxy->ifp->iff_nd_proxy, &proxy->next);

    /* Join the solicitated address */
    ipmip6_icmp_mc_solicitated_address(ctx,
                                       proc,
                                       IP_TRUE,
                                       proxy->ifp,
                                       proxy->addr);
    /* */
    proxy->sent = 1;

    /* Send an unsolicited neighbor advertisement */
    ipmip6_icmp_neighbor_advertisement(ctx, proc, proxy, IP_NULL, IP_TRUE);

    /* Insert a timeout */   
    ipmip_timer_cancel(&ctx->ipmip, proc, &proxy->unsolicited);
    ipmip_timer_request(&ctx->ipmip,
                        proc,
                        &proxy->unsolicited,
                        proxy->ifp->iff_lock,
                        (Ipmip_timer_func_t)ipmip6_nd_proxy_unsolicited_timeout_iflocked,
                        proxy,
                        IP_NULL,
                        IPMIP6_ND_NUD_RETRANS_TIMER);
}


/*
 *===========================================================================
 *                    ipmip6_nd_proxy_stop_iflocked
 *===========================================================================
 * Description: Start passive proxying for a given address
 * Parameters:  proxy   - The proxy object
 * Returns:     
 *
 */
IP_GLOBAL void
ipmip6_nd_proxy_stop_iflocked(Ipmip6_context_t       *ctx,
                              Ipmip_proc_t           *proc,
                              Ipmip6_nd_proxy_t      *proxy)
{
    /* Stop any previous proxy registrations */
    if (proxy->next.head != IP_NULL)
    {
        /* Remove this element from the proxy */
        ipcom_list_remove(&proxy->next);

        /* Leave the solicitated address */
        ipmip6_icmp_mc_solicitated_address(ctx,
                                           proc,
                                           IP_FALSE,
                                           proxy->ifp,
                                           proxy->addr);

        /* Remove the unsolicited timeout */
        ipmip_timer_cancel(&ctx->ipmip, proc, &proxy->unsolicited);
    }
}


/*
 *===========================================================================
 *                    ipmip6_nd_proxy_ns_recv
 *===========================================================================
 * Description: Receives a neighbor solicitation.
 * Parameters:  context - The context
 *              icmp    - The icmp header.
 *              len     - The total length of the icmp packet.
 *              name    - The name of the interface it arrived on.
 *              src     - The source address it want sent from.
 * Returns:     
 *
 */
IP_GLOBAL void 
ipmip6_nd_proxy_ns_recv(Ipmip6_context_t    *ctx,
                        Ipmip_proc_t        *proc,
                        Ipmip6_pktbuf_t     *pbuf)
{
    Ipmip6_if_t *ife = ipmip6_if_lockbyindex(ctx, proc, pbuf->ipmip.srcinfo.dst->ifindex);
    char buf[1024];

    IPMIP6_EVENT_IF(WARNING, proc, 
                    ipmip_log_event_add(&ctx->ipmip, 
                                        proc, 
                                        "Neighbor Solicitation received on %s",
                                        ipcom_if_indextoname(pbuf->ipmip.srcinfo.dst->ifindex, buf)));

    /* Located the required interface? */
    if (ife != IP_NULL)
    {
        Ipmip6_nd_proxy_t                       *proxy;
        Ipmip6_pkt_nd_neighbor_solicitation_t   *ns         = (Ipmip6_pkt_nd_neighbor_solicitation_t *) IPMIP_BUFFER_PTR(&pbuf->ipmip.packet);


        /* Sanity check */
        if (ns->nd_ns_hdr.icmp6_code != 0 || (Ip_size_t)IPMIP_BUFFER_SIZE(&pbuf->ipmip.packet) < sizeof(Ipmip6_pkt_nd_neighbor_solicitation_t))
        {
            IPMIP6_EVENT_IF(WARNING, proc, 
                            ipmip_log_event_add(&ctx->ipmip, 
                                                proc, 
                                                "Neighbor Solicitation received on %s is truncated or erronous",
                                                ife->iff.ifname));
            goto unlock_out;
        }


        for (proxy = IPCOM_LIST_FIRST(&ife->iff_nd_proxy); proxy != IP_NULL; proxy = IPCOM_LIST_NEXT(&proxy->next))
            if (IP_IN6_ARE_ADDR_EQUAL(proxy->addr, &ns->nd_ns_target))
                break;

        /* Found it? */
        if (proxy != IP_NULL)
            /* Send a solicited neighbor advertisement */
            ipmip6_icmp_neighbor_advertisement(ctx, proc, proxy, &pbuf->ipmip.srcinfo.src->sin6.sin6_addr, IP_FALSE);
    }

unlock_out:
    if (ife)
        ipmip6_if_release_iflocked(ctx,proc,ife);
    ipmip_pktbuf_free(&ctx->ipmip, proc, &pbuf->ipmip);
}

/*
 *===========================================================================
 *                    ipmip6_nd_proxy_init
 *===========================================================================
 * Description: Initialize a proxy structure
 * Parameters:  proxy   - The proxy object
 *              name    - The name of the proxy structure
 * Returns:     
 *
 */
IP_GLOBAL void 
ipmip6_nd_proxy_init(Ipmip6_nd_proxy_t   *proxy)
{
    /* Initialize the timeout */
    IPMIP_TIMER_INIT(&proxy->unsolicited);
}


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

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