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

  /*
   *	Bridge per vlan tunnel port dst_metadata netlink control interface
   *
   *	Authors:
   *	Roopa Prabhu		<roopa@cumulusnetworks.com>

   */
  
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/etherdevice.h>
  #include <net/rtnetlink.h>
  #include <net/net_namespace.h>
  #include <net/sock.h>
  #include <uapi/linux/if_bridge.h>
  #include <net/dst_metadata.h>
  
  #include "br_private.h"
  #include "br_private_tunnel.h"
  
  static size_t __get_vlan_tinfo_size(void)
  {
  	return nla_total_size(0) + /* nest IFLA_BRIDGE_VLAN_TUNNEL_INFO */
  		  nla_total_size(sizeof(u32)) + /* IFLA_BRIDGE_VLAN_TUNNEL_ID */
  		  nla_total_size(sizeof(u16)) + /* IFLA_BRIDGE_VLAN_TUNNEL_VID */
  		  nla_total_size(sizeof(u16)); /* IFLA_BRIDGE_VLAN_TUNNEL_FLAGS */
  }

  static bool vlan_tunid_inrange(struct net_bridge_vlan *v_curr,
  			       struct net_bridge_vlan *v_last)

  {

  	__be32 tunid_curr = tunnel_id_to_key32(v_curr->tinfo.tunnel_id);
  	__be32 tunid_last = tunnel_id_to_key32(v_last->tinfo.tunnel_id);

  	return (be32_to_cpu(tunid_curr) - be32_to_cpu(tunid_last)) == 1;

  }
  
  static int __get_num_vlan_tunnel_infos(struct net_bridge_vlan_group *vg)
  {

  	struct net_bridge_vlan *v, *vtbegin = NULL, *vtend = NULL;

  	int num_tinfos = 0;
  
  	/* Count number of vlan infos */
  	list_for_each_entry_rcu(v, &vg->vlan_list, vlist) {
  		/* only a context, bridge vlan not activated */
  		if (!br_vlan_should_use(v) || !v->tinfo.tunnel_id)
  			continue;

  		if (!vtbegin) {

  			goto initvars;

  		} else if ((v->vid - vtend->vid) == 1 &&
  			   vlan_tunid_inrange(v, vtend)) {
  			vtend = v;

  			continue;
  		} else {

  			if ((vtend->vid - vtbegin->vid) > 0)

  				num_tinfos += 2;
  			else
  				num_tinfos += 1;
  		}
  initvars:

  		vtbegin = v;
  		vtend = v;

  	}

  	if (vtbegin && vtend) {
  		if ((vtend->vid - vtbegin->vid) > 0)

  			num_tinfos += 2;
  		else
  			num_tinfos += 1;
  	}
  
  	return num_tinfos;
  }
  
  int br_get_vlan_tunnel_info_size(struct net_bridge_vlan_group *vg)
  {
  	int num_tinfos;
  
  	if (!vg)
  		return 0;
  
  	rcu_read_lock();
  	num_tinfos = __get_num_vlan_tunnel_infos(vg);
  	rcu_read_unlock();
  
  	return num_tinfos * __get_vlan_tinfo_size();
  }
  
  static int br_fill_vlan_tinfo(struct sk_buff *skb, u16 vid,
  			      __be64 tunnel_id, u16 flags)
  {
  	__be32 tid = tunnel_id_to_key32(tunnel_id);
  	struct nlattr *tmap;

  	tmap = nla_nest_start_noflag(skb, IFLA_BRIDGE_VLAN_TUNNEL_INFO);

  	if (!tmap)
  		return -EMSGSIZE;
  	if (nla_put_u32(skb, IFLA_BRIDGE_VLAN_TUNNEL_ID,
  			be32_to_cpu(tid)))
  		goto nla_put_failure;
  	if (nla_put_u16(skb, IFLA_BRIDGE_VLAN_TUNNEL_VID,
  			vid))
  		goto nla_put_failure;
  	if (nla_put_u16(skb, IFLA_BRIDGE_VLAN_TUNNEL_FLAGS,
  			flags))
  		goto nla_put_failure;
  	nla_nest_end(skb, tmap);
  
  	return 0;
  
  nla_put_failure:
  	nla_nest_cancel(skb, tmap);
  
  	return -EMSGSIZE;
  }
  
  static int br_fill_vlan_tinfo_range(struct sk_buff *skb,
  				    struct net_bridge_vlan *vtbegin,
  				    struct net_bridge_vlan *vtend)
  {
  	int err;

  	if (vtend && (vtend->vid - vtbegin->vid) > 0) {

  		/* add range to skb */
  		err = br_fill_vlan_tinfo(skb, vtbegin->vid,
  					 vtbegin->tinfo.tunnel_id,
  					 BRIDGE_VLAN_INFO_RANGE_BEGIN);
  		if (err)
  			return err;
  
  		err = br_fill_vlan_tinfo(skb, vtend->vid,
  					 vtend->tinfo.tunnel_id,
  					 BRIDGE_VLAN_INFO_RANGE_END);
  		if (err)
  			return err;
  	} else {
  		err = br_fill_vlan_tinfo(skb, vtbegin->vid,
  					 vtbegin->tinfo.tunnel_id,
  					 0);
  		if (err)
  			return err;
  	}
  
  	return 0;
  }
  
  int br_fill_vlan_tunnel_info(struct sk_buff *skb,
  			     struct net_bridge_vlan_group *vg)
  {
  	struct net_bridge_vlan *vtbegin = NULL;
  	struct net_bridge_vlan *vtend = NULL;
  	struct net_bridge_vlan *v;
  	int err;
  
  	/* Count number of vlan infos */
  	list_for_each_entry_rcu(v, &vg->vlan_list, vlist) {
  		/* only a context, bridge vlan not activated */
  		if (!br_vlan_should_use(v))
  			continue;
  
  		if (!v->tinfo.tunnel_dst)
  			continue;
  
  		if (!vtbegin) {
  			goto initvars;
  		} else if ((v->vid - vtend->vid) == 1 &&

  			    vlan_tunid_inrange(v, vtend)) {

  			vtend = v;
  			continue;
  		} else {
  			err = br_fill_vlan_tinfo_range(skb, vtbegin, vtend);
  			if (err)
  				return err;
  		}
  initvars:
  		vtbegin = v;
  		vtend = v;
  	}
  
  	if (vtbegin) {
  		err = br_fill_vlan_tinfo_range(skb, vtbegin, vtend);
  		if (err)
  			return err;
  	}
  
  	return 0;
  }
  
  static const struct nla_policy vlan_tunnel_policy[IFLA_BRIDGE_VLAN_TUNNEL_MAX + 1] = {
  	[IFLA_BRIDGE_VLAN_TUNNEL_ID] = { .type = NLA_U32 },
  	[IFLA_BRIDGE_VLAN_TUNNEL_VID] = { .type = NLA_U16 },
  	[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS] = { .type = NLA_U16 },
  };
  
  static int br_vlan_tunnel_info(struct net_bridge_port *p, int cmd,

  			       u16 vid, u32 tun_id, bool *changed)

  {
  	int err = 0;
  
  	if (!p)
  		return -EINVAL;
  
  	switch (cmd) {
  	case RTM_SETLINK:
  		err = nbp_vlan_tunnel_info_add(p, vid, tun_id);

  		if (!err)
  			*changed = true;

  		break;
  	case RTM_DELLINK:

  		if (!nbp_vlan_tunnel_info_delete(p, vid))
  			*changed = true;

  		break;
  	}
  
  	return err;
  }
  
  int br_parse_vlan_tunnel_info(struct nlattr *attr,
  			      struct vtunnel_info *tinfo)
  {
  	struct nlattr *tb[IFLA_BRIDGE_VLAN_TUNNEL_MAX + 1];
  	u32 tun_id;
  	u16 vid, flags = 0;
  	int err;
  
  	memset(tinfo, 0, sizeof(*tinfo));

  	err = nla_parse_nested_deprecated(tb, IFLA_BRIDGE_VLAN_TUNNEL_MAX,
  					  attr, vlan_tunnel_policy, NULL);

  	if (err < 0)
  		return err;

  	if (!tb[IFLA_BRIDGE_VLAN_TUNNEL_ID] ||
  	    !tb[IFLA_BRIDGE_VLAN_TUNNEL_VID])
  		return -EINVAL;

  	tun_id = nla_get_u32(tb[IFLA_BRIDGE_VLAN_TUNNEL_ID]);
  	vid = nla_get_u16(tb[IFLA_BRIDGE_VLAN_TUNNEL_VID]);
  	if (vid >= VLAN_VID_MASK)
  		return -ERANGE;
  
  	if (tb[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS])
  		flags = nla_get_u16(tb[IFLA_BRIDGE_VLAN_TUNNEL_FLAGS]);
  
  	tinfo->tunid = tun_id;
  	tinfo->vid = vid;
  	tinfo->flags = flags;
  
  	return 0;
  }
  
  int br_process_vlan_tunnel_info(struct net_bridge *br,
  				struct net_bridge_port *p, int cmd,
  				struct vtunnel_info *tinfo_curr,

  				struct vtunnel_info *tinfo_last,
  				bool *changed)

  {
  	int err;
  
  	if (tinfo_curr->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN) {
  		if (tinfo_last->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN)
  			return -EINVAL;
  		memcpy(tinfo_last, tinfo_curr, sizeof(struct vtunnel_info));
  	} else if (tinfo_curr->flags & BRIDGE_VLAN_INFO_RANGE_END) {
  		int t, v;
  
  		if (!(tinfo_last->flags & BRIDGE_VLAN_INFO_RANGE_BEGIN))
  			return -EINVAL;
  		if ((tinfo_curr->vid - tinfo_last->vid) !=
  		    (tinfo_curr->tunid - tinfo_last->tunid))
  			return -EINVAL;
  		t = tinfo_last->tunid;
  		for (v = tinfo_last->vid; v <= tinfo_curr->vid; v++) {

  			err = br_vlan_tunnel_info(p, cmd, v, t, changed);

  			if (err)
  				return err;
  			t++;
  		}
  		memset(tinfo_last, 0, sizeof(struct vtunnel_info));
  		memset(tinfo_curr, 0, sizeof(struct vtunnel_info));
  	} else {
  		if (tinfo_last->flags)
  			return -EINVAL;
  		err = br_vlan_tunnel_info(p, cmd, tinfo_curr->vid,

  					  tinfo_curr->tunid, changed);

  		if (err)
  			return err;
  		memset(tinfo_last, 0, sizeof(struct vtunnel_info));
  		memset(tinfo_curr, 0, sizeof(struct vtunnel_info));
  	}
  
  	return 0;
  }