// SPDX-License-Identifier: GPL-2.0-or-later

/* Ethernet-VPN Attribute handling file

 * Copyright (C) 2016 6WIND

 */

#include <zebra.h>

#include "command.h"

#include "filter.h"

#include "prefix.h"

#include "log.h"

#include "memory.h"

#include "stream.h"

#include "vxlan.h"

#include "bgpd/bgpd.h"

#include "bgpd/bgp_attr.h"

#include "bgpd/bgp_route.h"

#include "bgpd/bgp_attr_evpn.h"

#include "bgpd/bgp_ecommunity.h"

#include "bgpd/bgp_evpn.h"

#include "bgpd/bgp_evpn_private.h"

bool bgp_route_evpn_same(const struct bgp_route_evpn *e1,

       const struct bgp_route_evpn *e2)

{

  return (e1->type == e2->type &&

    !memcmp(&(e1->eth_s_id), &(e2->eth_s_id), sizeof(esi_t)) &&

    !ipaddr_cmp(&(e1->gw_ip), &(e2->gw_ip)));

}

void bgp_add_routermac_ecom(struct attr *attr, struct ethaddr *routermac)

{

  struct ecommunity_val routermac_ecom;

  struct ecommunity *ecomm = bgp_attr_get_ecommunity(attr);

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

  routermac_ecom.val[0] = ECOMMUNITY_ENCODE_EVPN;

  routermac_ecom.val[1] = ECOMMUNITY_EVPN_SUBTYPE_ROUTERMAC;

  memcpy(&routermac_ecom.val[2], routermac->octet, ETH_ALEN);

  if (!ecomm) {

    bgp_attr_set_ecommunity(attr, ecommunity_new());

    ecomm = bgp_attr_get_ecommunity(attr);

  }

  ecommunity_add_val(ecomm, &routermac_ecom, false, false);

  ecommunity_str(ecomm);

}

/* converts to an esi

 * returns 1 on success, 0 otherwise

 * format accepted: AA:BB:CC:DD:EE:FF:GG:HH:II:JJ

 * if id is null, check only is done

 */

bool str2esi(const char *str, esi_t *id)

{

  unsigned int a[ESI_BYTES];

  int i;

  if (!str)

    return false;

  if (sscanf(str, "%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x:%2x", a + 0, a + 1,

       a + 2, a + 3, a + 4, a + 5, a + 6, a + 7, a + 8, a + 9)

      != ESI_BYTES) {

    /* error in incoming str length */

    return false;

  }

  /* valid mac address */

  if (!id)

    return true;

  for (i = 0; i < ESI_BYTES; ++i)

    id->val[i] = a[i] & 0xff;

  return true;

}

char *ecom_mac2str(char *ecom_mac)

{

  char *en;

  en = ecom_mac;

  en += 2;

  return prefix_mac2str((struct ethaddr *)en, NULL, 0);

}

/* Fetch router-mac from extended community */

bool bgp_attr_rmac(struct attr *attr, struct ethaddr *rmac)

{

  uint32_t i = 0;

  struct ecommunity *ecom;

  ecom = bgp_attr_get_ecommunity(attr);

  if (!ecom || !ecom->size)

    return false;

  /* If there is a router mac extended community, set RMAC in attr */

  for (i = 0; i < ecom->size; i++) {

    uint8_t *pnt = NULL;

    uint8_t type = 0;

    uint8_t sub_type = 0;

    pnt = (ecom->val + (i * ECOMMUNITY_SIZE));

    type = *pnt++;

    sub_type = *pnt++;

    if (!(type == ECOMMUNITY_ENCODE_EVPN

          && sub_type == ECOMMUNITY_EVPN_SUBTYPE_ROUTERMAC))

      continue;

    memcpy(rmac, pnt, ETH_ALEN);

    return true;

  }

  return false;

}

/*

 * return true if attr contains default gw extended community

 */

uint8_t bgp_attr_default_gw(struct attr *attr)

{

  struct ecommunity *ecom;

  uint32_t i;

  ecom = bgp_attr_get_ecommunity(attr);

  if (!ecom || !ecom->size)

    return 0;

  /* If there is a default gw extendd community return true otherwise

   * return 0 */

  for (i = 0; i < ecom->size; i++) {

    uint8_t *pnt;

    uint8_t type, sub_type;

    pnt = (ecom->val + (i * ECOMMUNITY_SIZE));

    type = *pnt++;

    sub_type = *pnt++;

    if ((type == ECOMMUNITY_ENCODE_OPAQUE

         && sub_type == ECOMMUNITY_EVPN_SUBTYPE_DEF_GW))

      return 1;

  }

  return 0;

}

/*

 * Fetch and return the DF preference and algorithm from

 * DF election extended community, if present, else 0.

 */

uint16_t bgp_attr_df_pref_from_ec(struct attr *attr, uint8_t *alg)

{

  struct ecommunity *ecom;

  uint32_t i;

  uint16_t df_pref = 0;

  *alg = EVPN_MH_DF_ALG_SERVICE_CARVING;

  ecom = bgp_attr_get_ecommunity(attr);

  if (!ecom || !ecom->size)

    return 0;

  for (i = 0; i < ecom->size; i++) {

    uint8_t *pnt;

    uint8_t type, sub_type;

    pnt = (ecom->val + (i * ECOMMUNITY_SIZE));

    type = *pnt++;

    sub_type = *pnt++;

    if (!(type == ECOMMUNITY_ENCODE_EVPN

          && sub_type == ECOMMUNITY_EVPN_SUBTYPE_DF_ELECTION))

      continue;

    *alg = (*pnt++) & ECOMMUNITY_EVPN_SUBTYPE_DF_ALG_BITS;

    pnt += 3;

    pnt = ptr_get_be16(pnt, &df_pref);

    (void)pnt; /* consume value */

    break;

  }

  return df_pref;

}

/*

 * Fetch and return the sequence number from MAC Mobility extended

 * community, if present, else 0.

 */

uint32_t bgp_attr_mac_mobility_seqnum(struct attr *attr, uint8_t *sticky)

{

  struct ecommunity *ecom;

  uint32_t i;

  uint8_t flags = 0;

  ecom = bgp_attr_get_ecommunity(attr);

  if (!ecom || !ecom->size)

    return 0;

  /* If there is a MAC Mobility extended community, return its

   * sequence number.

   * TODO: RFC is silent on handling of multiple MAC mobility extended

   * communities for the same route. We will bail out upon the first

   * one.

   */

  for (i = 0; i < ecom->size; i++) {

    const uint8_t *pnt;

    uint8_t type, sub_type;

    uint32_t seq_num;

    pnt = (ecom->val + (i * ECOMMUNITY_SIZE));

    type = *pnt++;

    sub_type = *pnt++;

    if (!(type == ECOMMUNITY_ENCODE_EVPN

          && sub_type == ECOMMUNITY_EVPN_SUBTYPE_MACMOBILITY))

      continue;

    flags = *pnt++;

    if (flags & ECOMMUNITY_EVPN_SUBTYPE_MACMOBILITY_FLAG_STICKY)

      *sticky = 1;

    else

      *sticky = 0;

    pnt++;

    pnt = ptr_get_be32(pnt, &seq_num);

    (void)pnt; /* consume value */

    return seq_num;

  }

  return 0;

}

/*

 * return true if attr contains router flag extended community

 */

void bgp_attr_evpn_na_flag(struct attr *attr,

    uint8_t *router_flag, bool *proxy)

{

  struct ecommunity *ecom;

  uint32_t i;

  uint8_t val;

  ecom = bgp_attr_get_ecommunity(attr);

  if (!ecom || !ecom->size)

    return;

  /* If there is a evpn na extendd community set router_flag */

  for (i = 0; i < ecom->size; i++) {

    uint8_t *pnt;

    uint8_t type, sub_type;

    pnt = (ecom->val + (i * ECOMMUNITY_SIZE));

    type = *pnt++;

    sub_type = *pnt++;

    if (type == ECOMMUNITY_ENCODE_EVPN &&

        sub_type == ECOMMUNITY_EVPN_SUBTYPE_ND) {

      val = *pnt++;

      if (val & ECOMMUNITY_EVPN_SUBTYPE_ND_ROUTER_FLAG)

        *router_flag = 1;

      if (val & ECOMMUNITY_EVPN_SUBTYPE_PROXY_FLAG)

        *proxy = true;

      break;

    }

  }

}

/* dst prefix must be AF_INET or AF_INET6 prefix, to forge EVPN prefix */

extern int bgp_build_evpn_prefix(int evpn_type, uint32_t eth_tag,

         struct prefix *dst)

{

  struct evpn_addr *p_evpn_p;

  struct prefix p2;

  struct prefix *src = &p2;

  if (!dst || dst->family == 0)

    return -1;

  /* store initial prefix in src */

  prefix_copy(src, dst);

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

  p_evpn_p = &(dst->u.prefix_evpn);

  dst->family = AF_EVPN;

  p_evpn_p->route_type = evpn_type;

  if (evpn_type == BGP_EVPN_IP_PREFIX_ROUTE) {

    p_evpn_p->prefix_addr.eth_tag = eth_tag;

    p_evpn_p->prefix_addr.ip_prefix_length = p2.prefixlen;

    if (src->family == AF_INET) {

      SET_IPADDR_V4(&p_evpn_p->prefix_addr.ip);

      memcpy(&p_evpn_p->prefix_addr.ip.ipaddr_v4,

             &src->u.prefix4,

             sizeof(struct in_addr));

      dst->prefixlen = (uint16_t)PREFIX_LEN_ROUTE_TYPE_5_IPV4;

    } else {

      SET_IPADDR_V6(&p_evpn_p->prefix_addr.ip);

      memcpy(&p_evpn_p->prefix_addr.ip.ipaddr_v6,

             &src->u.prefix6,

             sizeof(struct in6_addr));

      dst->prefixlen = (uint16_t)PREFIX_LEN_ROUTE_TYPE_5_IPV6;

    }

  } else

    return -1;

  return 0;

}