/*

 * The olsr.org Optimized Link-State Routing daemon(olsrd)

 * Copyright (c) 2004, Andreas Tonnesen(andreto@olsr.org)

 * Copyright (c) 2007, Sven-Ola for the policy routing stuff

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * * Redistributions of source code must retain the above copyright

 *   notice, this list of conditions and the following disclaimer.

 * * Redistributions in binary form must reproduce the above copyright

 *   notice, this list of conditions and the following disclaimer in

 *   the documentation and/or other materials provided with the

 *   distribution.

 * * Neither the name of olsr.org, olsrd nor the names of its

 *   contributors may be used to endorse or promote products derived

 *   from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS

 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE

 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,

 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER

 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN

 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 *

 * Visit http://www.olsr.org for more information.

 *

 * If you find this software useful feel free to make a donation

 * to the project. For more information see the website or contact

 * the copyright holders.

 *

 */

#include "kernel_routes.h"

#include "ipc_frontend.h"

#include "log.h"

/* values for control flag to handle recursive route corrections 

 *  currently only requires in linux specific kernel_routes.c */

#define RT_ORIG_REQUEST 0

#define RT_RETRY_AFTER_ADD_GATEWAY 1

#define RT_RETRY_AFTER_DELETE_SIMILAR 2

#define RT_DELETE_SIMILAR_ROUTE 3

#define RT_AUTO_ADD_GATEWAY_ROUTE 4

#define RT_DELETE_SIMILAR_AUTO_ROUTE 5

#if !LINUX_POLICY_ROUTING

static int delete_all_inet_gws(void);

#else /* !LINUX_POLICY_ROUTING */

#include <assert.h>

#include <linux/types.h>

#include <linux/rtnetlink.h>

extern struct rtnl_handle rth;

struct olsr_rtreq {

  struct nlmsghdr n;

  struct rtmsg r;

  char buf[512];

};

#if LINUX_RTNETLINK_LISTEN

#include "ifnet.h"

#include "socket_parser.h"

int rtnetlink_register_socket(int rtnl_mgrp)

{

  int sock = socket(AF_NETLINK,SOCK_RAW,NETLINK_ROUTE);

  struct sockaddr_nl addr;

  if (sock<0) {

    OLSR_PRINTF(1,"could not create rtnetlink socket! %d",sock);

  }

  else {

    addr.nl_family = AF_NETLINK;

    addr.nl_pid = 0; //kernel will assign appropiate number instead of pid (which is already used by primaray rtnetlink socket to add/delete routes)

    addr.nl_groups = rtnl_mgrp;

    if (bind(sock,(struct sockaddr *)&addr,sizeof(addr))<0) {

      OLSR_PRINTF(1,"could not bind socket! (%d %s)",errno,strerror(errno));

    }

    else {

      add_olsr_socket(sock, &rtnetlink_read);

    }

    fcntl(sock, F_SETFL, O_NONBLOCK);

  }

  return sock;

}

static void netlink_process_link(struct nlmsghdr *h)

{

  struct ifinfomsg *ifi = (struct ifinfomsg *) NLMSG_DATA(h);

  struct interface *iface;

  struct olsr_if *tmp_if;

  iface = if_ifwithindex(ifi->ifi_index);

  if (iface == NULL) {

    return;

  }

  //all IFF flags: LOOPBACK,BROADCAST;POINTOPOINT;MULTICAST;NOARP;ALLMULTI;PROMISC;MASTER;SLAVE;DEBUG;DYNAMIC;AUTOMEDIA;PORTSEL;NOTRAILERS;UP;LOWER_UP;DORMANT

  /* check if interface is up and running? (a not running interface keeps its routes, so better not react like on ifdown!!??) */

  if (ifi->ifi_flags&IFF_UP) {

    OLSR_PRINTF(3,"interface %s changed but is still up! ", iface->int_name);

    return; //we are currently only interested in interfaces that are/go down

  } else {

    OLSR_PRINTF(1,"interface %s is down! ", iface->int_name);

  }

  //only for still configured interfaces (ifup has to be detected with regular interface polling)

  for (tmp_if = olsr_cnf->interfaces; tmp_if != NULL; tmp_if = tmp_if->next) {

    if (tmp_if->interf==iface) {

      OLSR_PRINTF(1,"-> removing %s from olsr config! ", iface->int_name);

      RemoveInterface(tmp_if,true);

      break;

    }

  }

}

void rtnetlink_read(int sock)

{

  int len, plen;

  struct iovec iov;

  struct sockaddr_nl nladdr;

  struct msghdr msg = {

    &nladdr,

    sizeof(nladdr),

    &iov,

    1,

    NULL,

    0,

    0

  };

  char buffer[4096];

  struct nlmsghdr *nlh = (struct nlmsghdr *)(ARM_NOWARN_ALIGN) buffer;

  int ret;

  iov.iov_base = (void *) buffer;

  iov.iov_len = sizeof(buffer);

  while (true) { //read until ret<0;

    ret=recvmsg(sock, &msg, 0);

    if (ret<0) {

      if (errno != EAGAIN) OLSR_PRINTF(1,"\nnetlink listen error %u - %s",errno,strerror(errno));

      return;

    }

    /*check message*/

    len = nlh->nlmsg_len;

    plen = len - sizeof(nlh);

    if (len > ret || plen < 0) {

      OLSR_PRINTF(1,"Malformed netlink message: "

             "len=%d left=%d plen=%d",

              len, ret, plen);

      return;

    }

    if ( (nlh->nlmsg_type == RTM_NEWLINK) || ( nlh->nlmsg_type == RTM_DELLINK) ) netlink_process_link(nlh);

  }

}

#endif /*linux_rtnetlink_listen*/

static void

olsr_netlink_addreq(struct olsr_rtreq *req, int type, const void *data, int len)

{

  struct rtattr *rta = (struct rtattr *)(ARM_NOWARN_ALIGN)(((char *)req) + NLMSG_ALIGN(req->n.nlmsg_len));

  req->n.nlmsg_len = NLMSG_ALIGN(req->n.nlmsg_len) + RTA_LENGTH(len);

  assert(req->n.nlmsg_len < sizeof(struct olsr_rtreq));

  rta->rta_type = type;

  rta->rta_len = RTA_LENGTH(len);

  memcpy(RTA_DATA(rta), data, len);

}

/* returns

 * -1 on unrecoverable error (calling function will have to handle it)

 *  0 on unexpected but recoverable rtnetlink behaviour

 *    but some of the implemented recovery methods only cure symptoms, 

 *    not the cause, like unintelligent ordering of inserted routes.

 *  1 on success */

static int

olsr_netlink_route_int(const struct rt_entry *rt, uint8_t family, uint8_t rttable, __u16 cmd, uint8_t flag)

{

  int ret = 1; /* helper variable for rtnetlink_message processing */

  int rt_ret = -2;  /* if no response from rtnetlink it must be considered as failed! */

  struct olsr_rtreq req;

  struct iovec iov;

  struct sockaddr_nl nladdr;

  struct msghdr msg = {

    &nladdr,

    sizeof(nladdr),

    &iov,

    1,

    NULL,

    0,

    0

  };

  uint32_t metric = 0;

  const struct rt_nexthop *nexthop = NULL;

  if ( ( cmd != RTM_NEWRULE ) && ( cmd != RTM_DELRULE ) ) {

    if (FIBM_FLAT == olsr_cnf->fib_metric) {

      metric = RT_METRIC_DEFAULT;

    }

    else {

      metric = (RTM_NEWROUTE == cmd) ? rt->rt_best->rtp_metric.hops : rt->rt_metric.hops;

    }

    if (( RTM_NEWROUTE == cmd ) ||

        (( RTM_DELROUTE == cmd ) && ( RT_DELETE_SIMILAR_ROUTE == flag || RT_DELETE_SIMILAR_AUTO_ROUTE == flag ))) {

      nexthop = &rt->rt_best->rtp_nexthop;

    }

    else {

      nexthop = &rt->rt_nexthop;

    }

  }

  memset(&req, 0, sizeof(req));

  req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));

  req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL | NLM_F_ACK;

  req.n.nlmsg_type = cmd;

  req.r.rtm_family = family;

  req.r.rtm_table = rttable;

  /* RTN_UNSPEC would be the wildcard, but blackhole broadcast or nat roules should usually not conflict */

  /* -> olsr only adds deletes unicast routes */

  req.r.rtm_type = RTN_UNICAST;

  /* wildcard to delete routes of all protos if no simlar-delete correct proto will get set below */

  req.r.rtm_protocol = RTPROT_UNSPEC;

  /* as wildcard for deletion */

  req.r.rtm_scope = RT_SCOPE_NOWHERE;

  if ( ( cmd != RTM_NEWRULE ) && ( cmd != RTM_DELRULE ) ) {

    req.r.rtm_dst_len = rt->rt_dst.prefix_len;

    /* do not specify much as we wanna delete similar/conflicting routes */

    if ( ( flag != RT_DELETE_SIMILAR_ROUTE ) && ( flag != RT_DELETE_SIMILAR_AUTO_ROUTE )) {

      /* 0 gets replaced by OS-specifc default (3)

       * 1 is reserved so we take 0 instead (this really makes some sense)

       * other numbers are used 1:1 */

      req.r.rtm_protocol = ( (olsr_cnf->rtproto<1) ? RTPROT_BOOT : ( (olsr_cnf->rtproto==1) ? 0 : olsr_cnf->rtproto) );

      req.r.rtm_scope = RT_SCOPE_LINK;

      /*add interface*/

      olsr_netlink_addreq(&req, RTA_OIF, &nexthop->iif_index, sizeof(nexthop->iif_index));

#if SOURCE_IP_ROUTES

      /* source ip here is based on now static olsr_cnf->main_addr in this olsr-0.5.6-r4, should be based on orignator-id in newer olsrds */

      if (AF_INET == family) {

        olsr_netlink_addreq(&req, RTA_PREFSRC, &olsr_cnf->main_addr.v4.s_addr, sizeof(olsr_cnf->main_addr.v4.s_addr));

      }

      else {

        olsr_netlink_addreq(&req, RTA_PREFSRC, &olsr_cnf->main_addr.v6.s6_addr, sizeof(olsr_cnf->main_addr.v6.s6_addr));

      }

#endif

    }

    /* metric is specified always as we can only delete one route per iteration, and wanna hit the correct one first */

    if (FIBM_APPROX != olsr_cnf->fib_metric || (RTM_NEWROUTE == cmd) ) {

      olsr_netlink_addreq(&req, RTA_PRIORITY, &metric, sizeof(metric));

    }

    /* make sure that netmask = /32 as this is an autogenarated route */

    if (( flag == RT_AUTO_ADD_GATEWAY_ROUTE ) || (flag == RT_DELETE_SIMILAR_AUTO_ROUTE) ) {

      req.r.rtm_dst_len = 32;

    }

    /* for ipv4 or ipv6 we add gateway if one is specified, 

    * or leave gateway away if we want to delete similar routes aswell, 

    * or even use the gateway as target if we add a auto-generated route, 

    * or if delete-similar to make insertion of auto-generated route possible */

    if (AF_INET == family) {

      if ( ( flag != RT_AUTO_ADD_GATEWAY_ROUTE ) && (flag != RT_DELETE_SIMILAR_ROUTE) && 

           ( flag != RT_DELETE_SIMILAR_AUTO_ROUTE) && (rt->rt_dst.prefix.v4.s_addr != nexthop->gateway.v4.s_addr) ) {

        olsr_netlink_addreq(&req, RTA_GATEWAY, &nexthop->gateway.v4, sizeof(nexthop->gateway.v4));

        req.r.rtm_scope = RT_SCOPE_UNIVERSE;

      }

      olsr_netlink_addreq(&req, RTA_DST, ( (flag == RT_AUTO_ADD_GATEWAY_ROUTE) || (flag == RT_DELETE_SIMILAR_AUTO_ROUTE) ) ? 

                          &nexthop->gateway.v4 : &rt->rt_dst.prefix.v4, sizeof(rt->rt_dst.prefix.v4));

    } else {

      if ( ( flag != RT_AUTO_ADD_GATEWAY_ROUTE ) && (flag != RT_DELETE_SIMILAR_ROUTE ) && ( flag != RT_DELETE_SIMILAR_AUTO_ROUTE) 

          && (0 != memcmp(&rt->rt_dst.prefix.v6, &nexthop->gateway.v6, sizeof(nexthop->gateway.v6))) ) {

        olsr_netlink_addreq(&req, RTA_GATEWAY, &nexthop->gateway.v6, sizeof(nexthop->gateway.v6));

        req.r.rtm_scope = RT_SCOPE_UNIVERSE;

      }

      olsr_netlink_addreq(&req, RTA_DST, ( (flag == RT_AUTO_ADD_GATEWAY_ROUTE) || (flag == RT_DELETE_SIMILAR_AUTO_ROUTE) ) ? 

                          &nexthop->gateway.v6 : &rt->rt_dst.prefix.v6, sizeof(rt->rt_dst.prefix.v6));

    }

  } else {

    /* add or delete a rule */

    static uint32_t priority = 65535;

    req.r.rtm_scope = RT_SCOPE_UNIVERSE;

    olsr_netlink_addreq(&req, RTA_PRIORITY, &priority, sizeof(priority));

  }

  iov.iov_base = &req.n;

  iov.iov_len = req.n.nlmsg_len;

  memset(&nladdr, 0, sizeof(nladdr));

  nladdr.nl_family = AF_NETLINK;

  if (0 <= (ret = sendmsg(olsr_cnf->rtnl_s, &msg, 0))) {

    iov.iov_base = req.buf;

    iov.iov_len = sizeof(req.buf);

    if (0 < (ret = recvmsg(olsr_cnf->rtnl_s, &msg, 0))) {

      struct nlmsghdr *h = (struct nlmsghdr *)(ARM_NOWARN_ALIGN)req.buf;

      while (NLMSG_OK(h, (unsigned int)ret)) {

        if (NLMSG_DONE == h->nlmsg_type) {

          /* seems to reached never */

          olsr_syslog(OLSR_LOG_INFO, "_received NLMSG_DONE");

          break;

        }

        if (NLMSG_ERROR == h->nlmsg_type) {

          if (NLMSG_LENGTH(sizeof(struct nlmsgerr) <= h->nlmsg_len)) {

            struct ipaddr_str ibuf;

            struct ipaddr_str gbuf;

            struct nlmsgerr *l_err = (struct nlmsgerr *)NLMSG_DATA(h);

            errno = -l_err->error;

            if (0 != errno) {

              const char *const err_msg = strerror(errno);

              struct ipaddr_str buf;

              rt_ret = -1;

              /* syslog debug output for various situations */

              if ( cmd == RTM_NEWRULE ) {

                olsr_syslog(OLSR_LOG_ERR,"Error '%s' (%d) on inserting empty policy rule aimed to activate RtTable %u!", err_msg, errno, rttable);

              }

              else if ( cmd == RTM_DELRULE ) {

                olsr_syslog(OLSR_LOG_ERR,"Error '%s' (%d) on deleting empty policy rule aimed to activate rtTable %u!", err_msg, errno, rttable);

              }

              else if ( flag <= RT_RETRY_AFTER_DELETE_SIMILAR ) {

                if (rt->rt_dst.prefix.v4.s_addr!=nexthop->gateway.v4.s_addr) {

                  olsr_syslog(OLSR_LOG_ERR, "error '%s' (%d) %s route to %s/%d via %s dev %s",

                      err_msg, errno, (cmd == RTM_NEWROUTE) ? "add" : "del",

                      olsr_ip_to_string(&ibuf,&rt->rt_dst.prefix), req.r.rtm_dst_len,

                      olsr_ip_to_string(&gbuf,&nexthop->gateway), if_ifwithindex_name(nexthop->iif_index));

                }

                else {

                  olsr_syslog(OLSR_LOG_ERR, "error '%s' (%d) %s route to %s/%d dev %s",

                      err_msg, errno, (cmd == RTM_NEWROUTE) ? "add" : "del",

                      olsr_ip_to_string(&ibuf,&rt->rt_dst.prefix), req.r.rtm_dst_len, if_ifwithindex_name(nexthop->iif_index));

                }

              }

              else if (flag == RT_AUTO_ADD_GATEWAY_ROUTE) {

                olsr_syslog(OLSR_LOG_ERR, ". error '%s' (%d) auto-add route to %s dev %s", err_msg, errno,

                    olsr_ip_to_string(&ibuf,&nexthop->gateway), if_ifwithindex_name(nexthop->iif_index));

              }

              else if (flag == RT_DELETE_SIMILAR_ROUTE) {

                olsr_syslog(OLSR_LOG_ERR, ". error '%s' (%d) auto-delete route to %s dev %s", err_msg, errno,

                    olsr_ip_to_string(&ibuf,&rt->rt_dst.prefix), if_ifwithindex_name(nexthop->iif_index));

              }

              else if (flag == RT_DELETE_SIMILAR_AUTO_ROUTE) {

                olsr_syslog(OLSR_LOG_ERR, ". . error '%s' (%d) auto-delete similar route to %s dev %s", err_msg, errno,

                    olsr_ip_to_string(&ibuf,&nexthop->gateway), if_ifwithindex_name(nexthop->iif_index));

              }

              else {

                /* should never happen */

                olsr_syslog(OLSR_LOG_ERR, "# invalid internal route delete/add flag (%d) used!", flag);

              }

            }

            else {

              /* netlink acks requests with an errno=0 NLMSG_ERROR response! */

              rt_ret = 1;

            }

            /* resolve "File exist" (17) propblems (on orig and autogen routes)*/	

            if ((errno == 17) && (cmd == RTM_NEWROUTE) && ((flag == RT_ORIG_REQUEST) || (flag == RT_AUTO_ADD_GATEWAY_ROUTE))) {

              /* a similar route going over another gateway may be present, which has to be deleted! */

              olsr_syslog(OLSR_LOG_ERR, ". auto-deleting similar routes to resolve 'File exists' (17) while adding route!");

              rt_ret = RT_DELETE_SIMILAR_ROUTE; /* processing will contiune after this loop */

            }

            /* report success on "No such process" (3) */

            else if ((errno == 3) && (cmd == RTM_DELROUTE) && (flag == RT_ORIG_REQUEST)) {

              /* another similar (but slightly different) route may be present at this point

              * , if so this will get solved when adding new route to this destination */

              olsr_syslog(OLSR_LOG_ERR, ". ignoring 'No such process' (3) while deleting route!");

              rt_ret = 0;

            }

            /* insert route to gateway on the fly if "Network unreachable" (128) on 2.4 kernels

             * or on 2.6 kernel No such process (3) or Network unreachable (101) is reported in rtnetlink response

             * do this only with flat metric, as using metric values inherited from 

             * a target behind the gateway is really strange, and could lead to multiple routes!

             * anyways if invalid gateway ips may happen we are f*cked up!!

             * but if not, these on the fly generated routes are no problem, and will only get used when needed */

            else if ( ( (errno == 3) || (errno == 101) || (errno == 128) )

                && (flag == RT_ORIG_REQUEST) && (FIBM_FLAT == olsr_cnf->fib_metric)

                     && (cmd == RTM_NEWROUTE) && (rt->rt_dst.prefix.v4.s_addr!=nexthop->gateway.v4.s_addr)) {

              if (errno == 128)  {

                olsr_syslog(OLSR_LOG_ERR, ". autogenerating route to handle 'Network unreachable' (128) while adding route!");

              }

              else if (errno == 101) {

                olsr_syslog(OLSR_LOG_ERR, ". autogenerating route to handle 'Network unreachable' (101) while adding route!");

              }

              else {

                olsr_syslog(OLSR_LOG_ERR, ". autogenerating route to handle 'No such process' (3) while adding route!");

              }

              /* processing will contiune after this loop */

              rt_ret = RT_AUTO_ADD_GATEWAY_ROUTE;

            }

          }

          /* report invalid message size */

          else {

            olsr_syslog(OLSR_LOG_INFO,"_received invalid netlink message size %lu != %u",

                (unsigned long int)sizeof(struct nlmsgerr), h->nlmsg_len);

          }

        }

        /* log all other messages */

        else {

          olsr_syslog(OLSR_LOG_INFO,"_received %u Byte rtnetlink response of type %u with seqnr %u and flags %u from %u (%u)",

              h->nlmsg_len, h->nlmsg_type, h->nlmsg_seq, h->nlmsg_flags, h->nlmsg_pid, NLMSG_ERROR);

        }

/*

 * The ARM compile complains about alignment. Copied

 * from /usr/include/linux/netlink.h and adapted for ARM

 */

#define MY_NLMSG_NEXT(nlh,len)	 ((len) -= NLMSG_ALIGN((nlh)->nlmsg_len), \

				  (struct nlmsghdr*)(ARM_NOWARN_ALIGN)(((char*)(nlh)) + NLMSG_ALIGN((nlh)->nlmsg_len)))

        h = MY_NLMSG_NEXT(h, ret);

      }

    }

  }

  if ( rt_ret == RT_DELETE_SIMILAR_ROUTE ) {

    /* delete all routes that may collide */

    /* recursive call to delete simlar routes, using flag 2 to invoke deletion of similar, not only exact matches*/

    rt_ret = olsr_netlink_route_int(rt, family, rttable, RTM_DELROUTE, 

        flag == RT_AUTO_ADD_GATEWAY_ROUTE ? RT_DELETE_SIMILAR_AUTO_ROUTE : RT_DELETE_SIMILAR_ROUTE);

    /* retry insert original route, if deleting similar succeeded, using flag=1 to prevent recursions */

    if (rt_ret > 0) {

      rt_ret = olsr_netlink_route_int(rt, family, rttable, RTM_NEWROUTE, RT_RETRY_AFTER_DELETE_SIMILAR);

    }

    else {

      olsr_syslog(OLSR_LOG_ERR, ". failed on auto-deleting similar route conflicting with above route!");

    }

    /* set appropriate return code for original request, while returning simple -1/1 if called recursive */

    if (flag != RT_AUTO_ADD_GATEWAY_ROUTE) {

      if (rt_ret > 0) {

        /* successful recovery */

        rt_ret = 0;

      }

      else {

        /* unrecoverable error */

        rt_ret = -1;

      }

    }

  }

  if ( rt_ret == RT_AUTO_ADD_GATEWAY_ROUTE ) {

    /* autoadd route via gateway */

    /* recursive call to invoke creation of a route to the gateway */

    rt_ret = olsr_netlink_route_int(rt, family, rttable, RTM_NEWROUTE, RT_AUTO_ADD_GATEWAY_ROUTE);

    /* retry insert original route, if above succeeded without problems */

    if (rt_ret > 0) {

      rt_ret = olsr_netlink_route_int(rt, family, rttable, RTM_NEWROUTE, RT_RETRY_AFTER_ADD_GATEWAY);

    }

    else {

      olsr_syslog(OLSR_LOG_ERR, ". failed on inserting auto-generated route to gateway of above route!");

    }

    /* set appropriate return code for original request*/

    if (rt_ret > 0) {

      /* successful recovery */

      rt_ret = 0;

    }

    else {

      /* unrecoverable error */

      rt_ret = -1;

    }

  }

  /* send ipc update on success */

  if ( ( cmd != RTM_NEWRULE ) && ( cmd != RTM_DELRULE )

      && (flag = RT_ORIG_REQUEST) && (0 <= rt_ret && olsr_cnf->ipc_connections > 0) ) {

    ipc_route_send_rtentry(&rt->rt_dst.prefix, &nexthop->gateway, metric,

        RTM_NEWROUTE == cmd, if_ifwithindex_name(nexthop->iif_index));

  }

  if (rt_ret == -2) {

    olsr_syslog(OLSR_LOG_ERR,"no rtnetlink response! (no system ressources left?, everything may happen now ...)");

  }

  return rt_ret;

}

/* external wrapper function for above patched multi purpose rtnetlink function */

int

olsr_netlink_rule(uint8_t family, uint8_t rttable, uint16_t cmd)

{

  return olsr_netlink_route_int(NULL, family, rttable, cmd, RT_ORIG_REQUEST);

}

/* internal wrapper function for above patched function */

static int

olsr_netlink_route(const struct rt_entry *rt, uint8_t family, uint8_t rttable, __u16 cmd)

{

  return olsr_netlink_route_int(rt, family, rttable, cmd, RT_ORIG_REQUEST);

}

#endif /* LINUX_POLICY_ROUTING */

/**

 * Insert a route in the kernel routing table

 *

 * @param destination the route to add

 *

 * @return negative on error

 */

int

olsr_ioctl_add_route(const struct rt_entry *rt)

{

#if !LINUX_POLICY_ROUTING

  struct rtentry kernel_route;

  union olsr_ip_addr mask;

  int rslt;

#endif /* LINUX_POLICY_ROUTING */

  OLSR_PRINTF(2, "KERN: Adding %s\n", olsr_rtp_to_string(rt->rt_best));

#if !LINUX_POLICY_ROUTING

  memset(&kernel_route, 0, sizeof(struct rtentry));

  ((struct sockaddr_in *)&kernel_route.rt_dst)->sin_family = AF_INET;

  ((struct sockaddr_in *)&kernel_route.rt_gateway)->sin_family = AF_INET;

  ((struct sockaddr_in *)&kernel_route.rt_genmask)->sin_family = AF_INET;

  ((struct sockaddr_in *)&kernel_route.rt_dst)->sin_addr = rt->rt_dst.prefix.v4;

  if (!olsr_prefix_to_netmask(&mask, rt->rt_dst.prefix_len)) {

    return -1;

  }

  ((struct sockaddr_in *)&kernel_route.rt_genmask)->sin_addr = mask.v4;

  if (rt->rt_dst.prefix.v4.s_addr != rt->rt_best->rtp_nexthop.gateway.v4.s_addr) {

    ((struct sockaddr_in *)&kernel_route.rt_gateway)->sin_addr = rt->rt_best->rtp_nexthop.gateway.v4;

  }

  kernel_route.rt_flags = olsr_rt_flags(rt);

  kernel_route.rt_metric = olsr_fib_metric(&rt->rt_best->rtp_metric.hops);

  /*

   * Set interface

   */

  kernel_route.rt_dev = if_ifwithindex_name(rt->rt_best->rtp_nexthop.iif_index);

  /* delete existing default route before ? */

  if ((olsr_cnf->del_gws) && (rt->rt_dst.prefix.v4.s_addr == INADDR_ANY) && (rt->rt_dst.prefix_len == INADDR_ANY)) {

    delete_all_inet_gws();

    olsr_cnf->del_gws = false;

  }

  if ((rslt = ioctl(olsr_cnf->ioctl_s, SIOCADDRT, &kernel_route)) >= 0) {

    /*

     * Send IPC route update message

     */

    ipc_route_send_rtentry(&rt->rt_dst.prefix, &rt->rt_best->rtp_nexthop.gateway, rt->rt_best->rtp_metric.hops, 1,

                           if_ifwithindex_name(rt->rt_best->rtp_nexthop.iif_index));

  }

  return rslt;

#else /* !LINUX_POLICY_ROUTING */

  if (0 == olsr_cnf->rttable_default && 0 == rt->rt_dst.prefix_len && 253 > olsr_cnf->rttable) {

    /*

     * Users start whining about not having internet with policy

     * routing activated and no static default route in table 254.

     * We maintain a fallback defroute in the default=253 table.

     */

    olsr_netlink_route(rt, AF_INET, 253, RTM_NEWROUTE);

  }

  if (0 == rt->rt_dst.prefix_len && olsr_cnf->rttable_default != 0) {

    return olsr_netlink_route(rt, AF_INET, olsr_cnf->rttable_default, RTM_NEWROUTE);

  }

  else {

    return olsr_netlink_route(rt, AF_INET, olsr_cnf->rttable, RTM_NEWROUTE);

  }

#endif /* LINUX_POLICY_ROUTING */

}

/**

 *Insert a route in the kernel routing table

 *

 *@param destination the route to add

 *

 *@return negative on error

 */

int

olsr_ioctl_add_route6(const struct rt_entry *rt)

{

#if !LINUX_POLICY_ROUTING

  struct in6_rtmsg kernel_route;

  int rslt;

  OLSR_PRINTF(2, "KERN: Adding %s\n", olsr_rtp_to_string(rt->rt_best));

  memset(&kernel_route, 0, sizeof(struct in6_rtmsg));

  kernel_route.rtmsg_dst = rt->rt_dst.prefix.v6;

  kernel_route.rtmsg_dst_len = rt->rt_dst.prefix_len;

  kernel_route.rtmsg_gateway = rt->rt_best->rtp_nexthop.gateway.v6;

  kernel_route.rtmsg_flags = olsr_rt_flags(rt);

  kernel_route.rtmsg_metric = olsr_fib_metric(&rt->rt_best->rtp_metric.hops);

  /*

   * set interface

   */

  kernel_route.rtmsg_ifindex = rt->rt_best->rtp_nexthop.iif_index;

  /* XXX delete 0/0 route before ? */

  if ((rslt = ioctl(olsr_cnf->ioctl_s, SIOCADDRT, &kernel_route)) >= 0) {

    /*

     * Send IPC route update message

     */

    ipc_route_send_rtentry(&rt->rt_dst.prefix, &rt->rt_best->rtp_nexthop.gateway, rt->rt_best->rtp_metric.hops, 1,

                           if_ifwithindex_name(rt->rt_best->rtp_nexthop.iif_index));

  }

  return rslt;

#else /* !LINUX_POLICY_ROUTING */

  if (0 == rt->rt_dst.prefix_len && olsr_cnf->rttable_default != 0) {

    return olsr_netlink_route(rt, AF_INET6, olsr_cnf->rttable_default, RTM_NEWROUTE);

  }

  else {

    return olsr_netlink_route(rt, AF_INET6, olsr_cnf->rttable, RTM_NEWROUTE);

  }

#endif /* LINUX_POLICY_ROUTING */

}

/**

 *Remove a route from the kernel

 *

 *@param destination the route to remove

 *

 *@return negative on error

 */

int

olsr_ioctl_del_route(const struct rt_entry *rt)

{

#if !LINUX_POLICY_ROUTING

  struct rtentry kernel_route;

  union olsr_ip_addr mask;

  int rslt;

#endif /* LINUX_POLICY_ROUTING */

  OLSR_PRINTF(2, "KERN: Deleting %s\n", olsr_rt_to_string(rt));

#if !LINUX_POLICY_ROUTING

  memset(&kernel_route, 0, sizeof(struct rtentry));

  ((struct sockaddr_in *)&kernel_route.rt_dst)->sin_family = AF_INET;

  ((struct sockaddr_in *)&kernel_route.rt_gateway)->sin_family = AF_INET;

  ((struct sockaddr_in *)&kernel_route.rt_genmask)->sin_family = AF_INET;

  ((struct sockaddr_in *)&kernel_route.rt_dst)->sin_addr = rt->rt_dst.prefix.v4;

  if (rt->rt_dst.prefix.v4.s_addr != rt->rt_nexthop.gateway.v4.s_addr) {

    ((struct sockaddr_in *)&kernel_route.rt_gateway)->sin_addr = rt->rt_nexthop.gateway.v4;

  }

  if (!olsr_prefix_to_netmask(&mask, rt->rt_dst.prefix_len)) {

    return -1;

  } else {

    ((struct sockaddr_in *)&kernel_route.rt_genmask)->sin_addr = mask.v4;

  }

  kernel_route.rt_flags = olsr_rt_flags(rt);

  kernel_route.rt_metric = olsr_fib_metric(&rt->rt_metric.hops);

  /*

   * Set interface

   */

  kernel_route.rt_dev = NULL;

  if ((rslt = ioctl(olsr_cnf->ioctl_s, SIOCDELRT, &kernel_route)) >= 0) {

    /*

     * Send IPC route update message

     */

    ipc_route_send_rtentry(&rt->rt_dst.prefix, NULL, 0, 0, NULL);

  }

  return rslt;

#else /* !LINUX_POLICY_ROUTING */

  if (0 == olsr_cnf->rttable_default && 0 == rt->rt_dst.prefix_len && 253 > olsr_cnf->rttable) {

    /*

     * Also remove the fallback default route

     */

    olsr_netlink_route(rt, AF_INET, 253, RTM_DELROUTE);

  }

  if (0 == rt->rt_dst.prefix_len && olsr_cnf->rttable_default != 0) {

    return olsr_netlink_route(rt, AF_INET, olsr_cnf->rttable_default, RTM_DELROUTE);

  }

  else {

    return olsr_netlink_route(rt, AF_INET, olsr_cnf->rttable, RTM_DELROUTE);

  }

#endif /* LINUX_POLICY_ROUTING */

}

/**

 *Remove a route from the kernel

 *

 *@param destination the route to remove

 *

 *@return negative on error

 */

int

olsr_ioctl_del_route6(const struct rt_entry *rt)

{

#if !LINUX_POLICY_ROUTING

  struct in6_rtmsg kernel_route;

  int rslt;

#endif /* LINUX_POLICY_ROUTING */

  OLSR_PRINTF(2, "KERN: Deleting %s\n", olsr_rt_to_string(rt));

#if !LINUX_POLICY_ROUTING

  memset(&kernel_route, 0, sizeof(struct in6_rtmsg));

  kernel_route.rtmsg_dst = rt->rt_dst.prefix.v6;

  kernel_route.rtmsg_dst_len = rt->rt_dst.prefix_len;

  kernel_route.rtmsg_gateway = rt->rt_best->rtp_nexthop.gateway.v6;

  kernel_route.rtmsg_flags = olsr_rt_flags(rt);

  kernel_route.rtmsg_metric = olsr_fib_metric(&rt->rt_best->rtp_metric.hops);

  if ((rslt = ioctl(olsr_cnf->ioctl_s, SIOCDELRT, &kernel_route) >= 0)) {

    /*

     * Send IPC route update message

     */

    ipc_route_send_rtentry(&rt->rt_dst.prefix, NULL, 0, 0, NULL);

  }

  return rslt;

#else /* !LINUX_POLICY_ROUTING */

  if (0 == rt->rt_dst.prefix_len && olsr_cnf->rttable_default != 0) {

    return olsr_netlink_route(rt, AF_INET6, olsr_cnf->rttable_default, RTM_DELROUTE);

  }

  else {

    return olsr_netlink_route(rt, AF_INET6, olsr_cnf->rttable, RTM_DELROUTE);

  }

#endif /* LINUX_POLICY_ROUTING */

}

#if !LINUX_POLICY_ROUTING

static int

delete_all_inet_gws(void)

{

  int s;

  char buf[BUFSIZ], *cp, *cplim;

  struct ifconf ifc;

  struct ifreq *ifr;

  OLSR_PRINTF(1, "Internet gateway detected...\nTrying to delete default gateways\n");

  /* Get a socket */

  if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {

    olsr_syslog(OLSR_LOG_ERR, "socket: %m");

    return -1;

  }

  ifc.ifc_len = sizeof(buf);

  ifc.ifc_buf = buf;

  if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {

    olsr_syslog(OLSR_LOG_ERR, "ioctl (get interface configuration)");

    close(s);

    return -1;

  }

  ifr = ifc.ifc_req;

  cplim = buf + ifc.ifc_len;    /*skip over if's with big ifr_addr's */

  for (cp = buf; cp < cplim; cp += sizeof(ifr->ifr_name) + sizeof(ifr->ifr_addr)) {

    struct rtentry kernel_route;

    ifr = (struct ifreq *)cp;

    if (strcmp(ifr->ifr_ifrn.ifrn_name, "lo") == 0) {

      OLSR_PRINTF(1, "Skipping loopback...\n");

      continue;

    }

    OLSR_PRINTF(1, "Trying 0.0.0.0/0 %s...", ifr->ifr_ifrn.ifrn_name);

    memset(&kernel_route, 0, sizeof(struct rtentry));

    ((struct sockaddr_in *)&kernel_route.rt_dst)->sin_addr.s_addr = 0;

    ((struct sockaddr_in *)&kernel_route.rt_dst)->sin_family = AF_INET;

    ((struct sockaddr_in *)&kernel_route.rt_genmask)->sin_addr.s_addr = 0;

    ((struct sockaddr_in *)&kernel_route.rt_genmask)->sin_family = AF_INET;

    ((struct sockaddr_in *)&kernel_route.rt_gateway)->sin_addr.s_addr = INADDR_ANY;

    ((struct sockaddr_in *)&kernel_route.rt_gateway)->sin_family = AF_INET;

    kernel_route.rt_flags = RTF_UP | RTF_GATEWAY;

    kernel_route.rt_dev = ifr->ifr_ifrn.ifrn_name;

    if ((ioctl(s, SIOCDELRT, &kernel_route)) < 0)

      OLSR_PRINTF(1, "NO\n");

    else

      OLSR_PRINTF(1, "YES\n");

  }

  close(s);

  return 0;

}

#endif /* LINUX_POLICY_ROUTING */

/*

 * Local Variables:

 * c-basic-offset: 2

 * indent-tabs-mode: nil

 * End:

 */