/*

 *

 *   Authors:

 *    Lars Fenneberg    <lf@elemental.net>

 *

 *   This software is Copyright 1996,1997 by the above mentioned author(s),

 *   All Rights Reserved.

 *

 *   The license which is distributed with this software in the file COPYRIGHT

 *   applies to this software. If your distribution is missing this file, you

 *   may request it from https://github.com/radvd-project/radvd/issues

 *

 */

#include "config.h"

#include "defaults.h"

#include "includes.h"

#include "radvd.h"

#define IFACE_SETUP_DELAY 1

void iface_init_defaults(struct Interface *iface)

{

  memset(iface, 0, sizeof(struct Interface));

  iface->state_info.changed = 1;

  iface->IgnoreIfMissing = DFLT_IgnoreIfMissing;

  iface->AdvSendAdvert = DFLT_AdvSendAdv;

  iface->MaxRtrAdvInterval = DFLT_MaxRtrAdvInterval;

  iface->AdvSourceLLAddress = DFLT_AdvSourceLLAddress;

  iface->RemoveAdvOnExit = DFLT_RemoveAdvOnExit;

  iface->MinDelayBetweenRAs = DFLT_MinDelayBetweenRAs;

  iface->MinRtrAdvInterval = -1;

  iface->UnicastOnly = DFLT_UnicastOnly;

  iface->UnrestrictedUnicast = DFLT_UnrestrictedUnicast;

  iface->AdvRASolicitedUnicast = DFLT_AdvRASolicitedUnicast;

  iface->ra_header_info.AdvDefaultPreference = DFLT_AdvDefaultPreference;

  iface->ra_header_info.AdvDefaultLifetime = -1;

  iface->ra_header_info.AdvReachableTime = DFLT_AdvReachableTime;

  iface->ra_header_info.AdvRetransTimer = DFLT_AdvRetransTimer;

  iface->ra_header_info.AdvCurHopLimit = DFLT_AdvCurHopLimit;

  iface->ra_header_info.AdvHomeAgentFlag = DFLT_AdvHomeAgentFlag;

  iface->mipv6.AdvIntervalOpt = DFLT_AdvIntervalOpt;

  iface->mipv6.AdvHomeAgentInfo = DFLT_AdvHomeAgentInfo;

  iface->mipv6.HomeAgentPreference = DFLT_HomeAgentPreference;

  iface->mipv6.AdvMobRtrSupportFlag = DFLT_AdvMobRtrSupportFlag;

  iface->mipv6.HomeAgentLifetime = -1;

  iface->AdvLinkMTU = DFLT_AdvLinkMTU;

  iface->AdvRAMTU = DFLT_AdvRAMTU;

}

void touch_iface(struct Interface *iface)

{

  iface->state_info.changed = 1;

  iface->state_info.ready = 0;

  iface->state_info.racount = 0;

  reschedule_iface(iface, 0);

}

int setup_iface(int sock, struct Interface *iface)

{

  iface->state_info.changed = 0;

  iface->state_info.ready = 0;

  /* The device index must be setup first so we can search it later */

  if (update_device_index(iface) < 0) {

    return -1;

  }

  /* Check IFF_UP, IFF_RUNNING and IFF_MULTICAST */

  if (check_device(sock, iface) < 0) {

    return -2;

  }

  /* Set iface->max_mtu and iface hardware address */

  if (update_device_info(sock, iface) < 0) {

    return -3;

  }

  /* Make sure the settings in the config file for this interface are ok (this depends

   * on iface->max_mtu already being set). */

  if (check_iface(iface) < 0) {

    return -4;

  }

  /* Save the first link local address seen on the specified interface to

   * iface->props.if_addr and keep a list off all addrs in iface->props.if_addrs */

  if (setup_iface_addrs(iface) < 0) {

    return -5;

  }

  /* Check if we a usable RA source address */

  if (iface->props.if_addr_rasrc == NULL) {

    dlog(LOG_DEBUG, 5, "no configured AdvRASrcAddress present, skipping send");

    return -6;

  }

  /* join the allrouters multicast group so we get the solicitations */

  if (setup_allrouters_membership(sock, iface) < 0) {

    return -7;

  }

  iface->state_info.ready = 1;

  dlog(LOG_DEBUG, 4, "%s is ready", iface->props.name);

  return 0;

}

int cleanup_iface(int sock, struct Interface *iface)

{

  /* leave the allrouters multicast group */

  cleanup_allrouters_membership(sock, iface);

  return 0;

}

void prefix_init_defaults(struct AdvPrefix *prefix)

{

  memset(prefix, 0, sizeof(struct AdvPrefix));

  prefix->AdvOnLinkFlag = DFLT_AdvOnLinkFlag;

  prefix->AdvAutonomousFlag = DFLT_AdvAutonomousFlag;

  prefix->AdvRouterAddr = DFLT_AdvRouterAddr;

  prefix->AdvDHCPv6PDPreferredFlag = DFLT_AdvDHCPv6PDPreferredFlag;

  prefix->AdvValidLifetime = DFLT_AdvValidLifetime;

  prefix->AdvPreferredLifetime = DFLT_AdvPreferredLifetime;

  prefix->DeprecatePrefixFlag = DFLT_DeprecatePrefixFlag;

  prefix->DecrementLifetimesFlag = DFLT_DecrementLifetimesFlag;

  prefix->curr_validlft = prefix->AdvValidLifetime;

  prefix->curr_preferredlft = prefix->AdvPreferredLifetime;

}

void nat64prefix_init_defaults(struct NAT64Prefix *prefix, struct Interface *iface)

{

  memset(prefix, 0, sizeof(struct NAT64Prefix));

  prefix->AdvValidLifetime = min(DFLT_NAT64MaxValidLifetime, 3*(iface->MaxRtrAdvInterval));

  prefix->curr_validlft = prefix->AdvValidLifetime;

}

void route_init_defaults(struct AdvRoute *route, struct Interface *iface)

{

  memset(route, 0, sizeof(struct AdvRoute));

  route->AdvRouteLifetime = DFLT_AdvRouteLifetime(iface);

  route->AdvRoutePreference = DFLT_AdvRoutePreference;

  route->RemoveRouteFlag = DFLT_RemoveRouteFlag;

}

void rdnss_init_defaults(struct AdvRDNSS *rdnss, struct Interface *iface)

{

  memset(rdnss, 0, sizeof(struct AdvRDNSS));

  rdnss->AdvRDNSSLifetime = DFLT_AdvRDNSSLifetime(iface);

  rdnss->AdvRDNSSNumber = 0;

  rdnss->FlushRDNSSFlag = DFLT_FlushRDNSSFlag;

}

void dnssl_init_defaults(struct AdvDNSSL *dnssl, struct Interface *iface)

{

  memset(dnssl, 0, sizeof(struct AdvDNSSL));

  dnssl->AdvDNSSLLifetime = DFLT_AdvDNSSLLifetime(iface);

  dnssl->FlushDNSSLFlag = DFLT_FlushDNSSLFlag;

}

int check_iface(struct Interface *iface)

{

  int res = 0;

  int MIPv6 = 0;

  struct in6_addr zeroaddr;

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

  /* Check if we use Mobile IPv6 extensions */

  if (iface->ra_header_info.AdvHomeAgentFlag || iface->mipv6.AdvHomeAgentInfo || iface->mipv6.AdvIntervalOpt) {

    MIPv6 = 1;

    flog(LOG_INFO, "using Mobile IPv6 extensions");

  }

  /* Check forwarding on interface */

  if (check_ip6_iface_forwarding(iface->props.name) < 1) {

    flog(LOG_WARNING, "IPv6 forwarding on interface seems to be disabled, but continuing anyway");

  }

  struct AdvPrefix *prefix = iface->AdvPrefixList;

  while (!MIPv6 && prefix) {

    if (prefix->AdvRouterAddr) {

      MIPv6 = 1;

    }

    prefix = prefix->next;

  }

  if (iface->MinRtrAdvInterval < 0)

    iface->MinRtrAdvInterval = DFLT_MinRtrAdvInterval(iface);

  if ((iface->MinRtrAdvInterval < (MIPv6 ? MIN_MinRtrAdvInterval_MIPv6 : MIN_MinRtrAdvInterval)) ||

      (iface->MinRtrAdvInterval > MAX_MinRtrAdvInterval(iface))) {

    flog(LOG_ERR,

         "MinRtrAdvInterval for %s (%.2f) must be at least %.2f but no more than 3/4 of MaxRtrAdvInterval (%.2f)",

         iface->props.name, iface->MinRtrAdvInterval,

         MIPv6 ? MIN_MinRtrAdvInterval_MIPv6 : (int)MIN_MinRtrAdvInterval, MAX_MinRtrAdvInterval(iface));

    res = -1;

  }

  if ((iface->MaxRtrAdvInterval < (MIPv6 ? MIN_MaxRtrAdvInterval_MIPv6 : MIN_MaxRtrAdvInterval)) ||

      (iface->MaxRtrAdvInterval > MAX_MaxRtrAdvInterval)) {

    flog(LOG_ERR, "MaxRtrAdvInterval for %s (%.2f) must be between %.2f and %d", iface->props.name,

         iface->MaxRtrAdvInterval, MIPv6 ? MIN_MaxRtrAdvInterval_MIPv6 : (int)MIN_MaxRtrAdvInterval,

         MAX_MaxRtrAdvInterval);

    res = -1;

  }

  if (iface->MinDelayBetweenRAs < (MIPv6 ? MIN_DELAY_BETWEEN_RAS_MIPv6 : MIN_DELAY_BETWEEN_RAS)) {

    flog(LOG_ERR, "MinDelayBetweenRAs for %s (%.2f) must be at least %.2f", iface->props.name,

         iface->MinDelayBetweenRAs, MIPv6 ? MIN_DELAY_BETWEEN_RAS_MIPv6 : MIN_DELAY_BETWEEN_RAS);

    res = -1;

  }

  if ((iface->AdvLinkMTU != 0) && ((iface->AdvLinkMTU < MIN_AdvLinkMTU) ||

           (iface->sllao.if_maxmtu != -1 && (iface->AdvLinkMTU > iface->sllao.if_maxmtu)))) {

    flog(LOG_ERR, "AdvLinkMTU for %s (%u) must be zero or between %u and %u", iface->props.name, iface->AdvLinkMTU,

         MIN_AdvLinkMTU, iface->sllao.if_maxmtu);

    res = -1;

  }

  if (iface->ra_header_info.AdvReachableTime > MAX_AdvReachableTime) {

    flog(LOG_ERR, "AdvReachableTime for %s (%u) must not be greater than %u", iface->props.name,

         iface->ra_header_info.AdvReachableTime, MAX_AdvReachableTime);

    res = -1;

  }

  if (iface->ra_header_info.AdvDefaultLifetime < 0)

    iface->ra_header_info.AdvDefaultLifetime = DFLT_AdvDefaultLifetime(iface);

  if ((iface->ra_header_info.AdvDefaultLifetime != 0) &&

      ((iface->ra_header_info.AdvDefaultLifetime > MAX_AdvDefaultLifetime) ||

       (iface->ra_header_info.AdvDefaultLifetime < MIN_AdvDefaultLifetime(iface)))) {

    flog(LOG_ERR, "AdvDefaultLifetime for %s (%u) must be zero or between %u and %u", iface->props.name,

         iface->ra_header_info.AdvDefaultLifetime, (int)MIN_AdvDefaultLifetime(iface), MAX_AdvDefaultLifetime);

    res = -1;

  }

  /* Mobile IPv6 ext */

  if (iface->mipv6.HomeAgentLifetime < 0)

    iface->mipv6.HomeAgentLifetime = DFLT_HomeAgentLifetime(iface);

  /* Mobile IPv6 ext */

  if (iface->mipv6.AdvHomeAgentInfo) {

    if ((iface->mipv6.HomeAgentLifetime > MAX_HomeAgentLifetime) ||

        (iface->mipv6.HomeAgentLifetime < MIN_HomeAgentLifetime)) {

      flog(LOG_ERR, "HomeAgentLifetime for %s (%u) must be between %u and %u", iface->props.name,

           iface->mipv6.HomeAgentLifetime, MIN_HomeAgentLifetime, MAX_HomeAgentLifetime);

      res = -1;

    }

  }

  /* Mobile IPv6 ext */

  if (iface->mipv6.AdvHomeAgentInfo && !(iface->ra_header_info.AdvHomeAgentFlag)) {

    flog(LOG_ERR, "AdvHomeAgentFlag for %s must be set with HomeAgentInfo", iface->props.name);

    res = -1;

  }

  if (iface->mipv6.AdvMobRtrSupportFlag && !(iface->mipv6.AdvHomeAgentInfo)) {

    flog(LOG_ERR, "AdvHomeAgentInfo for %s must be set with AdvMobRtrSupportFlag", iface->props.name);

    res = -1;

  }

  /* XXX: need this? prefix = iface->AdvPrefixList; */

  while (prefix) {

    if (prefix->PrefixLen > MAX_PrefixLen) {

      flog(LOG_ERR, "invalid prefix length (%u) for %s", prefix->PrefixLen, iface->props.name);

      res = -1;

    }

    if (prefix->AdvPreferredLifetime > prefix->AdvValidLifetime) {

      flog(LOG_ERR, "AdvValidLifetime for %s (%u) must be "

              "greater than or equal to AdvPreferredLifetime for",

           iface->props.name, prefix->AdvValidLifetime);

      res = -1;

    }

    prefix = prefix->next;

  }

  struct AdvRoute *route = iface->AdvRouteList;

  while (route) {

    if (route->PrefixLen > MAX_PrefixLen) {

      flog(LOG_ERR, "invalid route prefix length (%u) for %s", route->PrefixLen, iface->props.name);

      res = -1;

    }

    /* For the default route 0::/0, we need to explicitly check the

     * lifetime against the AdvDefaultLifetime value.

     *

     * If exactly one of the two has a zero value, then nodes processing

     * the RA may have a flap in their default route.

     *

     * AdvDefaultLifetime == 0 && route.AdvRouteLifetime > 0:

     * - default route is deleted and then re-added.

     * AdvDefaultLifetime > 0 && route.AdvRouteLifetime == 0:

     * - default route is added and then deleted.

     */

    if (IN6_IS_ADDR_UNSPECIFIED(&(route->Prefix))) {

      int route_zerolife = (route->AdvRouteLifetime == 0);

      int defaultroute_zerolife = (iface->ra_header_info.AdvDefaultLifetime == 0);

      if (route_zerolife ^ defaultroute_zerolife) {

        flog(

            LOG_ERR,

            "route 0::/0 lifetime (%u) conflicts with AdvDefaultLifetime (%u), default routes will flap!",

            route->AdvRouteLifetime, iface->ra_header_info.AdvDefaultLifetime);

        // res = -1; // In some future version, abort on this configuration error.

      }

    }

    route = route->next;

  }

  return res;

}

struct Interface *find_iface_by_index(struct Interface *iface, int index)

{

  for (; iface; iface = iface->next) {

    if (iface->props.if_index == index) {

      return iface;

    }

  }

  return 0;

}

struct Interface *find_iface_by_name(struct Interface *iface, const char *name)

{

  if (!name) {

    return 0;

  }

  for (; iface; iface = iface->next) {

    if (strcmp(iface->props.name, name) == 0) {

      return iface;

    }

  }

  return 0;

}

struct Interface *find_iface_by_time(struct Interface *iface)

{

  if (!iface) {

    return 0;

  }

  int timeout = next_time_msec(iface);

  struct Interface *next = iface;

  for (iface = iface->next; iface; iface = iface->next) {

    int t = next_time_msec(iface);

    if (timeout > t) {

      timeout = t;

      next = iface;

    }

  }

  return next;

}

void reschedule_iface(struct Interface *iface, double next)

{

#ifdef HAVE_NETLINK

  if (!iface->state_info.changed && !iface->state_info.ready) {

    next = 10 * iface->MaxRtrAdvInterval;

  } else if (next == 0) {

    next = IFACE_SETUP_DELAY;

  } else

#endif

      if (iface->state_info.racount < MAX_INITIAL_RTR_ADVERTISEMENTS) {

    next = min(MAX_INITIAL_RTR_ADVERT_INTERVAL, iface->MaxRtrAdvInterval);

  }

  dlog(LOG_DEBUG, 5, "%s next scheduled RA in %g second(s)", iface->props.name, next);

  iface->times.next_multicast = next_timespec(next);

}

void for_each_iface(struct Interface *ifaces, void (*foo)(struct Interface *, void *), void *data)

{

  for (; ifaces; ifaces = ifaces->next) {

    foo(ifaces, data);

  }

}

static void free_iface_list(struct Interface *iface)

{

  while (iface) {

    struct Interface *next_iface = iface->next;

    dlog(LOG_DEBUG, 4, "freeing interface %s", iface->props.name);

    struct AdvPrefix *prefix = iface->AdvPrefixList;

    while (prefix) {

      struct AdvPrefix *next_prefix = prefix->next;

      free(prefix);

      prefix = next_prefix;

    }

    struct AdvRoute *route = iface->AdvRouteList;

    while (route) {

      struct AdvRoute *next_route = route->next;

      free(route);

      route = next_route;

    }

    struct AdvRDNSS *rdnss = iface->AdvRDNSSList;

    while (rdnss) {

      struct AdvRDNSS *next_rdnss = rdnss->next;

      free(rdnss->AdvRDNSSAddr);

      free(rdnss);

      rdnss = next_rdnss;

    }

    struct AdvDNSSL *dnssl = iface->AdvDNSSLList;

    while (dnssl) {

      struct AdvDNSSL *next_dnssl = dnssl->next;

      for (int i = 0; i < dnssl->AdvDNSSLNumber; i++)

        free(dnssl->AdvDNSSLSuffixes[i]);

      free(dnssl->AdvDNSSLSuffixes);

      free(dnssl);

      dnssl = next_dnssl;

    }

    struct AutogenIgnorePrefix *ignore_prefixes = iface->IgnorePrefixList;

    while (ignore_prefixes) {

      struct AutogenIgnorePrefix *next_ignore_prefix = ignore_prefixes->next;

      free(ignore_prefixes);

      ignore_prefixes = next_ignore_prefix;

    }

    struct Clients *clients = iface->ClientList;

    while (clients) {

      struct Clients *next_client = clients->next;

      free(clients);

      clients = next_client;

    }

    free(iface->props.if_addrs);

    free(iface->AdvCaptivePortalAPI);

    free(iface);

    iface = next_iface;

  }

}

void free_ifaces(struct Interface *ifaces)

{

  dlog(LOG_DEBUG, 3, "Freeing Interfaces");

  free_iface_list(ifaces);

}