/*
   * net/sched/cls_flower.c		Flower classifier
   *
   * Copyright (c) 2015 Jiri Pirko <jiri@resnulli.us>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   */
  
  #include <linux/kernel.h>
  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/rhashtable.h>
  
  #include <linux/if_ether.h>
  #include <linux/in6.h>
  #include <linux/ip.h>
  
  #include <net/sch_generic.h>
  #include <net/pkt_cls.h>
  #include <net/ip.h>
  #include <net/flow_dissector.h>

  #include <net/dst.h>
  #include <net/dst_metadata.h>

  struct fl_flow_key {
  	int	indev_ifindex;

  	struct flow_dissector_key_control control;

  	struct flow_dissector_key_control enc_control;

  	struct flow_dissector_key_basic basic;
  	struct flow_dissector_key_eth_addrs eth;

  	struct flow_dissector_key_vlan vlan;

  	union {

  		struct flow_dissector_key_ipv4_addrs ipv4;

  		struct flow_dissector_key_ipv6_addrs ipv6;
  	};
  	struct flow_dissector_key_ports tp;

  	struct flow_dissector_key_keyid enc_key_id;
  	union {
  		struct flow_dissector_key_ipv4_addrs enc_ipv4;
  		struct flow_dissector_key_ipv6_addrs enc_ipv6;
  	};

  } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */
  
  struct fl_flow_mask_range {
  	unsigned short int start;
  	unsigned short int end;
  };
  
  struct fl_flow_mask {
  	struct fl_flow_key key;
  	struct fl_flow_mask_range range;
  	struct rcu_head	rcu;
  };
  
  struct cls_fl_head {
  	struct rhashtable ht;
  	struct fl_flow_mask mask;
  	struct flow_dissector dissector;
  	u32 hgen;
  	bool mask_assigned;
  	struct list_head filters;
  	struct rhashtable_params ht_params;
  	struct rcu_head rcu;
  };
  
  struct cls_fl_filter {
  	struct rhash_head ht_node;
  	struct fl_flow_key mkey;
  	struct tcf_exts exts;
  	struct tcf_result res;
  	struct fl_flow_key key;
  	struct list_head list;
  	u32 handle;

  	u32 flags;

  	struct rcu_head	rcu;
  };
  
  static unsigned short int fl_mask_range(const struct fl_flow_mask *mask)
  {
  	return mask->range.end - mask->range.start;
  }
  
  static void fl_mask_update_range(struct fl_flow_mask *mask)
  {
  	const u8 *bytes = (const u8 *) &mask->key;
  	size_t size = sizeof(mask->key);
  	size_t i, first = 0, last = size - 1;
  
  	for (i = 0; i < sizeof(mask->key); i++) {
  		if (bytes[i]) {
  			if (!first && i)
  				first = i;
  			last = i;
  		}
  	}
  	mask->range.start = rounddown(first, sizeof(long));
  	mask->range.end = roundup(last + 1, sizeof(long));
  }
  
  static void *fl_key_get_start(struct fl_flow_key *key,
  			      const struct fl_flow_mask *mask)
  {
  	return (u8 *) key + mask->range.start;
  }
  
  static void fl_set_masked_key(struct fl_flow_key *mkey, struct fl_flow_key *key,
  			      struct fl_flow_mask *mask)
  {
  	const long *lkey = fl_key_get_start(key, mask);
  	const long *lmask = fl_key_get_start(&mask->key, mask);
  	long *lmkey = fl_key_get_start(mkey, mask);
  	int i;
  
  	for (i = 0; i < fl_mask_range(mask); i += sizeof(long))
  		*lmkey++ = *lkey++ & *lmask++;
  }
  
  static void fl_clear_masked_range(struct fl_flow_key *key,
  				  struct fl_flow_mask *mask)
  {
  	memset(fl_key_get_start(key, mask), 0, fl_mask_range(mask));
  }
  
  static int fl_classify(struct sk_buff *skb, const struct tcf_proto *tp,
  		       struct tcf_result *res)
  {
  	struct cls_fl_head *head = rcu_dereference_bh(tp->root);
  	struct cls_fl_filter *f;
  	struct fl_flow_key skb_key;
  	struct fl_flow_key skb_mkey;

  	struct ip_tunnel_info *info;

  	if (!atomic_read(&head->ht.nelems))
  		return -1;

  	fl_clear_masked_range(&skb_key, &head->mask);

  
  	info = skb_tunnel_info(skb);
  	if (info) {
  		struct ip_tunnel_key *key = &info->key;
  
  		switch (ip_tunnel_info_af(info)) {
  		case AF_INET:
  			skb_key.enc_ipv4.src = key->u.ipv4.src;
  			skb_key.enc_ipv4.dst = key->u.ipv4.dst;
  			break;
  		case AF_INET6:
  			skb_key.enc_ipv6.src = key->u.ipv6.src;
  			skb_key.enc_ipv6.dst = key->u.ipv6.dst;
  			break;
  		}
  
  		skb_key.enc_key_id.keyid = tunnel_id_to_key32(key->tun_id);
  	}

  	skb_key.indev_ifindex = skb->skb_iif;
  	/* skb_flow_dissect() does not set n_proto in case an unknown protocol,
  	 * so do it rather here.
  	 */
  	skb_key.basic.n_proto = skb->protocol;

  	skb_flow_dissect(skb, &head->dissector, &skb_key, 0);

  
  	fl_set_masked_key(&skb_mkey, &skb_key, &head->mask);
  
  	f = rhashtable_lookup_fast(&head->ht,
  				   fl_key_get_start(&skb_mkey, &head->mask),
  				   head->ht_params);

  	if (f && !tc_skip_sw(f->flags)) {

  		*res = f->res;
  		return tcf_exts_exec(skb, &f->exts, res);
  	}
  	return -1;
  }
  
  static int fl_init(struct tcf_proto *tp)
  {
  	struct cls_fl_head *head;
  
  	head = kzalloc(sizeof(*head), GFP_KERNEL);
  	if (!head)
  		return -ENOBUFS;
  
  	INIT_LIST_HEAD_RCU(&head->filters);
  	rcu_assign_pointer(tp->root, head);
  
  	return 0;
  }
  
  static void fl_destroy_filter(struct rcu_head *head)
  {
  	struct cls_fl_filter *f = container_of(head, struct cls_fl_filter, rcu);
  
  	tcf_exts_destroy(&f->exts);
  	kfree(f);
  }

  static void fl_hw_destroy_filter(struct tcf_proto *tp, unsigned long cookie)

  {
  	struct net_device *dev = tp->q->dev_queue->dev;
  	struct tc_cls_flower_offload offload = {0};
  	struct tc_to_netdev tc;

  	if (!tc_should_offload(dev, tp, 0))

  		return;
  
  	offload.command = TC_CLSFLOWER_DESTROY;
  	offload.cookie = cookie;
  
  	tc.type = TC_SETUP_CLSFLOWER;
  	tc.cls_flower = &offload;
  
  	dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol, &tc);
  }

  static int fl_hw_replace_filter(struct tcf_proto *tp,
  				struct flow_dissector *dissector,
  				struct fl_flow_key *mask,
  				struct fl_flow_key *key,
  				struct tcf_exts *actions,
  				unsigned long cookie, u32 flags)

  {
  	struct net_device *dev = tp->q->dev_queue->dev;
  	struct tc_cls_flower_offload offload = {0};
  	struct tc_to_netdev tc;

  	int err;

  	if (!tc_should_offload(dev, tp, flags))

  		return tc_skip_sw(flags) ? -EINVAL : 0;

  
  	offload.command = TC_CLSFLOWER_REPLACE;
  	offload.cookie = cookie;
  	offload.dissector = dissector;
  	offload.mask = mask;
  	offload.key = key;
  	offload.exts = actions;
  
  	tc.type = TC_SETUP_CLSFLOWER;
  	tc.cls_flower = &offload;

  	err = dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol,
  					    &tc);

  
  	if (tc_skip_sw(flags))
  		return err;
  
  	return 0;

  }

  static void fl_hw_update_stats(struct tcf_proto *tp, struct cls_fl_filter *f)
  {
  	struct net_device *dev = tp->q->dev_queue->dev;
  	struct tc_cls_flower_offload offload = {0};
  	struct tc_to_netdev tc;

  	if (!tc_should_offload(dev, tp, 0))

  		return;
  
  	offload.command = TC_CLSFLOWER_STATS;
  	offload.cookie = (unsigned long)f;
  	offload.exts = &f->exts;
  
  	tc.type = TC_SETUP_CLSFLOWER;
  	tc.cls_flower = &offload;
  
  	dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol, &tc);
  }

  static bool fl_destroy(struct tcf_proto *tp, bool force)
  {
  	struct cls_fl_head *head = rtnl_dereference(tp->root);
  	struct cls_fl_filter *f, *next;
  
  	if (!force && !list_empty(&head->filters))
  		return false;
  
  	list_for_each_entry_safe(f, next, &head->filters, list) {

  		fl_hw_destroy_filter(tp, (unsigned long)f);

  		list_del_rcu(&f->list);
  		call_rcu(&f->rcu, fl_destroy_filter);
  	}
  	RCU_INIT_POINTER(tp->root, NULL);
  	if (head->mask_assigned)
  		rhashtable_destroy(&head->ht);
  	kfree_rcu(head, rcu);
  	return true;
  }
  
  static unsigned long fl_get(struct tcf_proto *tp, u32 handle)
  {
  	struct cls_fl_head *head = rtnl_dereference(tp->root);
  	struct cls_fl_filter *f;
  
  	list_for_each_entry(f, &head->filters, list)
  		if (f->handle == handle)
  			return (unsigned long) f;
  	return 0;
  }
  
  static const struct nla_policy fl_policy[TCA_FLOWER_MAX + 1] = {
  	[TCA_FLOWER_UNSPEC]		= { .type = NLA_UNSPEC },
  	[TCA_FLOWER_CLASSID]		= { .type = NLA_U32 },
  	[TCA_FLOWER_INDEV]		= { .type = NLA_STRING,
  					    .len = IFNAMSIZ },
  	[TCA_FLOWER_KEY_ETH_DST]	= { .len = ETH_ALEN },
  	[TCA_FLOWER_KEY_ETH_DST_MASK]	= { .len = ETH_ALEN },
  	[TCA_FLOWER_KEY_ETH_SRC]	= { .len = ETH_ALEN },
  	[TCA_FLOWER_KEY_ETH_SRC_MASK]	= { .len = ETH_ALEN },
  	[TCA_FLOWER_KEY_ETH_TYPE]	= { .type = NLA_U16 },
  	[TCA_FLOWER_KEY_IP_PROTO]	= { .type = NLA_U8 },
  	[TCA_FLOWER_KEY_IPV4_SRC]	= { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_IPV4_SRC_MASK]	= { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_IPV4_DST]	= { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_IPV4_DST_MASK]	= { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_IPV6_SRC]	= { .len = sizeof(struct in6_addr) },
  	[TCA_FLOWER_KEY_IPV6_SRC_MASK]	= { .len = sizeof(struct in6_addr) },
  	[TCA_FLOWER_KEY_IPV6_DST]	= { .len = sizeof(struct in6_addr) },
  	[TCA_FLOWER_KEY_IPV6_DST_MASK]	= { .len = sizeof(struct in6_addr) },
  	[TCA_FLOWER_KEY_TCP_SRC]	= { .type = NLA_U16 },
  	[TCA_FLOWER_KEY_TCP_DST]	= { .type = NLA_U16 },

  	[TCA_FLOWER_KEY_UDP_SRC]	= { .type = NLA_U16 },
  	[TCA_FLOWER_KEY_UDP_DST]	= { .type = NLA_U16 },

  	[TCA_FLOWER_KEY_VLAN_ID]	= { .type = NLA_U16 },
  	[TCA_FLOWER_KEY_VLAN_PRIO]	= { .type = NLA_U8 },
  	[TCA_FLOWER_KEY_VLAN_ETH_TYPE]	= { .type = NLA_U16 },

  	[TCA_FLOWER_KEY_ENC_KEY_ID]	= { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_ENC_IPV4_SRC]	= { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_ENC_IPV4_SRC_MASK] = { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_ENC_IPV4_DST]	= { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_ENC_IPV4_DST_MASK] = { .type = NLA_U32 },
  	[TCA_FLOWER_KEY_ENC_IPV6_SRC]	= { .len = sizeof(struct in6_addr) },
  	[TCA_FLOWER_KEY_ENC_IPV6_SRC_MASK] = { .len = sizeof(struct in6_addr) },
  	[TCA_FLOWER_KEY_ENC_IPV6_DST]	= { .len = sizeof(struct in6_addr) },
  	[TCA_FLOWER_KEY_ENC_IPV6_DST_MASK] = { .len = sizeof(struct in6_addr) },

  	[TCA_FLOWER_KEY_TCP_SRC_MASK]	= { .type = NLA_U16 },
  	[TCA_FLOWER_KEY_TCP_DST_MASK]	= { .type = NLA_U16 },
  	[TCA_FLOWER_KEY_UDP_SRC_MASK]	= { .type = NLA_U16 },
  	[TCA_FLOWER_KEY_UDP_DST_MASK]	= { .type = NLA_U16 },

  };
  
  static void fl_set_key_val(struct nlattr **tb,
  			   void *val, int val_type,
  			   void *mask, int mask_type, int len)
  {
  	if (!tb[val_type])
  		return;
  	memcpy(val, nla_data(tb[val_type]), len);
  	if (mask_type == TCA_FLOWER_UNSPEC || !tb[mask_type])
  		memset(mask, 0xff, len);
  	else
  		memcpy(mask, nla_data(tb[mask_type]), len);
  }

  static void fl_set_key_vlan(struct nlattr **tb,
  			    struct flow_dissector_key_vlan *key_val,
  			    struct flow_dissector_key_vlan *key_mask)
  {
  #define VLAN_PRIORITY_MASK	0x7
  
  	if (tb[TCA_FLOWER_KEY_VLAN_ID]) {
  		key_val->vlan_id =
  			nla_get_u16(tb[TCA_FLOWER_KEY_VLAN_ID]) & VLAN_VID_MASK;
  		key_mask->vlan_id = VLAN_VID_MASK;
  	}
  	if (tb[TCA_FLOWER_KEY_VLAN_PRIO]) {
  		key_val->vlan_priority =
  			nla_get_u8(tb[TCA_FLOWER_KEY_VLAN_PRIO]) &
  			VLAN_PRIORITY_MASK;
  		key_mask->vlan_priority = VLAN_PRIORITY_MASK;
  	}
  }

  static int fl_set_key(struct net *net, struct nlattr **tb,
  		      struct fl_flow_key *key, struct fl_flow_key *mask)
  {

  	__be16 ethertype;

  #ifdef CONFIG_NET_CLS_IND

  	if (tb[TCA_FLOWER_INDEV]) {

  		int err = tcf_change_indev(net, tb[TCA_FLOWER_INDEV]);

  		if (err < 0)
  			return err;
  		key->indev_ifindex = err;
  		mask->indev_ifindex = 0xffffffff;
  	}

  #endif

  
  	fl_set_key_val(tb, key->eth.dst, TCA_FLOWER_KEY_ETH_DST,
  		       mask->eth.dst, TCA_FLOWER_KEY_ETH_DST_MASK,
  		       sizeof(key->eth.dst));
  	fl_set_key_val(tb, key->eth.src, TCA_FLOWER_KEY_ETH_SRC,
  		       mask->eth.src, TCA_FLOWER_KEY_ETH_SRC_MASK,
  		       sizeof(key->eth.src));

  	if (tb[TCA_FLOWER_KEY_ETH_TYPE]) {

  		ethertype = nla_get_be16(tb[TCA_FLOWER_KEY_ETH_TYPE]);

  		if (ethertype == htons(ETH_P_8021Q)) {
  			fl_set_key_vlan(tb, &key->vlan, &mask->vlan);
  			fl_set_key_val(tb, &key->basic.n_proto,
  				       TCA_FLOWER_KEY_VLAN_ETH_TYPE,
  				       &mask->basic.n_proto, TCA_FLOWER_UNSPEC,
  				       sizeof(key->basic.n_proto));
  		} else {
  			key->basic.n_proto = ethertype;
  			mask->basic.n_proto = cpu_to_be16(~0);
  		}

  	}

  	if (key->basic.n_proto == htons(ETH_P_IP) ||
  	    key->basic.n_proto == htons(ETH_P_IPV6)) {
  		fl_set_key_val(tb, &key->basic.ip_proto, TCA_FLOWER_KEY_IP_PROTO,
  			       &mask->basic.ip_proto, TCA_FLOWER_UNSPEC,
  			       sizeof(key->basic.ip_proto));
  	}

  
  	if (tb[TCA_FLOWER_KEY_IPV4_SRC] || tb[TCA_FLOWER_KEY_IPV4_DST]) {
  		key->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;

  		fl_set_key_val(tb, &key->ipv4.src, TCA_FLOWER_KEY_IPV4_SRC,
  			       &mask->ipv4.src, TCA_FLOWER_KEY_IPV4_SRC_MASK,
  			       sizeof(key->ipv4.src));
  		fl_set_key_val(tb, &key->ipv4.dst, TCA_FLOWER_KEY_IPV4_DST,
  			       &mask->ipv4.dst, TCA_FLOWER_KEY_IPV4_DST_MASK,
  			       sizeof(key->ipv4.dst));

  	} else if (tb[TCA_FLOWER_KEY_IPV6_SRC] || tb[TCA_FLOWER_KEY_IPV6_DST]) {
  		key->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;

  		fl_set_key_val(tb, &key->ipv6.src, TCA_FLOWER_KEY_IPV6_SRC,
  			       &mask->ipv6.src, TCA_FLOWER_KEY_IPV6_SRC_MASK,
  			       sizeof(key->ipv6.src));
  		fl_set_key_val(tb, &key->ipv6.dst, TCA_FLOWER_KEY_IPV6_DST,
  			       &mask->ipv6.dst, TCA_FLOWER_KEY_IPV6_DST_MASK,
  			       sizeof(key->ipv6.dst));
  	}

  	if (key->basic.ip_proto == IPPROTO_TCP) {
  		fl_set_key_val(tb, &key->tp.src, TCA_FLOWER_KEY_TCP_SRC,

  			       &mask->tp.src, TCA_FLOWER_KEY_TCP_SRC_MASK,

  			       sizeof(key->tp.src));
  		fl_set_key_val(tb, &key->tp.dst, TCA_FLOWER_KEY_TCP_DST,

  			       &mask->tp.dst, TCA_FLOWER_KEY_TCP_DST_MASK,

  			       sizeof(key->tp.dst));
  	} else if (key->basic.ip_proto == IPPROTO_UDP) {
  		fl_set_key_val(tb, &key->tp.src, TCA_FLOWER_KEY_UDP_SRC,

  			       &mask->tp.src, TCA_FLOWER_KEY_UDP_SRC_MASK,

  			       sizeof(key->tp.src));
  		fl_set_key_val(tb, &key->tp.dst, TCA_FLOWER_KEY_UDP_DST,

  			       &mask->tp.dst, TCA_FLOWER_KEY_UDP_DST_MASK,

  			       sizeof(key->tp.dst));
  	}

  	if (tb[TCA_FLOWER_KEY_ENC_IPV4_SRC] ||
  	    tb[TCA_FLOWER_KEY_ENC_IPV4_DST]) {
  		key->enc_control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
  		fl_set_key_val(tb, &key->enc_ipv4.src,
  			       TCA_FLOWER_KEY_ENC_IPV4_SRC,
  			       &mask->enc_ipv4.src,
  			       TCA_FLOWER_KEY_ENC_IPV4_SRC_MASK,
  			       sizeof(key->enc_ipv4.src));
  		fl_set_key_val(tb, &key->enc_ipv4.dst,
  			       TCA_FLOWER_KEY_ENC_IPV4_DST,
  			       &mask->enc_ipv4.dst,
  			       TCA_FLOWER_KEY_ENC_IPV4_DST_MASK,
  			       sizeof(key->enc_ipv4.dst));
  	}
  
  	if (tb[TCA_FLOWER_KEY_ENC_IPV6_SRC] ||
  	    tb[TCA_FLOWER_KEY_ENC_IPV6_DST]) {
  		key->enc_control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
  		fl_set_key_val(tb, &key->enc_ipv6.src,
  			       TCA_FLOWER_KEY_ENC_IPV6_SRC,
  			       &mask->enc_ipv6.src,
  			       TCA_FLOWER_KEY_ENC_IPV6_SRC_MASK,
  			       sizeof(key->enc_ipv6.src));
  		fl_set_key_val(tb, &key->enc_ipv6.dst,
  			       TCA_FLOWER_KEY_ENC_IPV6_DST,
  			       &mask->enc_ipv6.dst,
  			       TCA_FLOWER_KEY_ENC_IPV6_DST_MASK,
  			       sizeof(key->enc_ipv6.dst));
  	}
  
  	fl_set_key_val(tb, &key->enc_key_id.keyid, TCA_FLOWER_KEY_ENC_KEY_ID,

  		       &mask->enc_key_id.keyid, TCA_FLOWER_UNSPEC,

  		       sizeof(key->enc_key_id.keyid));

  	return 0;
  }
  
  static bool fl_mask_eq(struct fl_flow_mask *mask1,
  		       struct fl_flow_mask *mask2)
  {
  	const long *lmask1 = fl_key_get_start(&mask1->key, mask1);
  	const long *lmask2 = fl_key_get_start(&mask2->key, mask2);
  
  	return !memcmp(&mask1->range, &mask2->range, sizeof(mask1->range)) &&
  	       !memcmp(lmask1, lmask2, fl_mask_range(mask1));
  }
  
  static const struct rhashtable_params fl_ht_params = {
  	.key_offset = offsetof(struct cls_fl_filter, mkey), /* base offset */
  	.head_offset = offsetof(struct cls_fl_filter, ht_node),
  	.automatic_shrinking = true,
  };
  
  static int fl_init_hashtable(struct cls_fl_head *head,
  			     struct fl_flow_mask *mask)
  {
  	head->ht_params = fl_ht_params;
  	head->ht_params.key_len = fl_mask_range(mask);
  	head->ht_params.key_offset += mask->range.start;
  
  	return rhashtable_init(&head->ht, &head->ht_params);
  }
  
  #define FL_KEY_MEMBER_OFFSET(member) offsetof(struct fl_flow_key, member)
  #define FL_KEY_MEMBER_SIZE(member) (sizeof(((struct fl_flow_key *) 0)->member))

  #define FL_KEY_IS_MASKED(mask, member)						\
  	memchr_inv(((char *)mask) + FL_KEY_MEMBER_OFFSET(member),		\
  		   0, FL_KEY_MEMBER_SIZE(member))				\

  
  #define FL_KEY_SET(keys, cnt, id, member)					\
  	do {									\
  		keys[cnt].key_id = id;						\
  		keys[cnt].offset = FL_KEY_MEMBER_OFFSET(member);		\
  		cnt++;								\
  	} while(0);

  #define FL_KEY_SET_IF_MASKED(mask, keys, cnt, id, member)			\

  	do {									\

  		if (FL_KEY_IS_MASKED(mask, member))				\

  			FL_KEY_SET(keys, cnt, id, member);			\
  	} while(0);
  
  static void fl_init_dissector(struct cls_fl_head *head,
  			      struct fl_flow_mask *mask)
  {
  	struct flow_dissector_key keys[FLOW_DISSECTOR_KEY_MAX];
  	size_t cnt = 0;

  	FL_KEY_SET(keys, cnt, FLOW_DISSECTOR_KEY_CONTROL, control);

  	FL_KEY_SET(keys, cnt, FLOW_DISSECTOR_KEY_BASIC, basic);

  	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
  			     FLOW_DISSECTOR_KEY_ETH_ADDRS, eth);
  	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
  			     FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4);
  	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
  			     FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6);
  	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
  			     FLOW_DISSECTOR_KEY_PORTS, tp);

  	FL_KEY_SET_IF_MASKED(&mask->key, keys, cnt,
  			     FLOW_DISSECTOR_KEY_VLAN, vlan);

  
  	skb_flow_dissector_init(&head->dissector, keys, cnt);
  }
  
  static int fl_check_assign_mask(struct cls_fl_head *head,
  				struct fl_flow_mask *mask)
  {
  	int err;
  
  	if (head->mask_assigned) {
  		if (!fl_mask_eq(&head->mask, mask))
  			return -EINVAL;
  		else
  			return 0;
  	}
  
  	/* Mask is not assigned yet. So assign it and init hashtable
  	 * according to that.
  	 */
  	err = fl_init_hashtable(head, mask);
  	if (err)
  		return err;
  	memcpy(&head->mask, mask, sizeof(head->mask));
  	head->mask_assigned = true;
  
  	fl_init_dissector(head, mask);
  
  	return 0;
  }
  
  static int fl_set_parms(struct net *net, struct tcf_proto *tp,
  			struct cls_fl_filter *f, struct fl_flow_mask *mask,
  			unsigned long base, struct nlattr **tb,
  			struct nlattr *est, bool ovr)
  {
  	struct tcf_exts e;
  	int err;

  	err = tcf_exts_init(&e, TCA_FLOWER_ACT, 0);

  	if (err < 0)
  		return err;

  	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
  	if (err < 0)
  		goto errout;

  
  	if (tb[TCA_FLOWER_CLASSID]) {
  		f->res.classid = nla_get_u32(tb[TCA_FLOWER_CLASSID]);
  		tcf_bind_filter(tp, &f->res, base);
  	}
  
  	err = fl_set_key(net, tb, &f->key, &mask->key);
  	if (err)
  		goto errout;
  
  	fl_mask_update_range(mask);
  	fl_set_masked_key(&f->mkey, &f->key, mask);
  
  	tcf_exts_change(tp, &f->exts, &e);
  
  	return 0;
  errout:
  	tcf_exts_destroy(&e);
  	return err;
  }
  
  static u32 fl_grab_new_handle(struct tcf_proto *tp,
  			      struct cls_fl_head *head)
  {
  	unsigned int i = 0x80000000;
  	u32 handle;
  
  	do {
  		if (++head->hgen == 0x7FFFFFFF)
  			head->hgen = 1;
  	} while (--i > 0 && fl_get(tp, head->hgen));
  
  	if (unlikely(i == 0)) {
  		pr_err("Insufficient number of handles
  ");
  		handle = 0;
  	} else {
  		handle = head->hgen;
  	}
  
  	return handle;
  }
  
  static int fl_change(struct net *net, struct sk_buff *in_skb,
  		     struct tcf_proto *tp, unsigned long base,
  		     u32 handle, struct nlattr **tca,
  		     unsigned long *arg, bool ovr)
  {
  	struct cls_fl_head *head = rtnl_dereference(tp->root);
  	struct cls_fl_filter *fold = (struct cls_fl_filter *) *arg;
  	struct cls_fl_filter *fnew;
  	struct nlattr *tb[TCA_FLOWER_MAX + 1];
  	struct fl_flow_mask mask = {};
  	int err;
  
  	if (!tca[TCA_OPTIONS])
  		return -EINVAL;
  
  	err = nla_parse_nested(tb, TCA_FLOWER_MAX, tca[TCA_OPTIONS], fl_policy);
  	if (err < 0)
  		return err;
  
  	if (fold && handle && fold->handle != handle)
  		return -EINVAL;
  
  	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
  	if (!fnew)
  		return -ENOBUFS;

  	err = tcf_exts_init(&fnew->exts, TCA_FLOWER_ACT, 0);
  	if (err < 0)
  		goto errout;

  
  	if (!handle) {
  		handle = fl_grab_new_handle(tp, head);
  		if (!handle) {
  			err = -EINVAL;
  			goto errout;
  		}
  	}
  	fnew->handle = handle;

  	if (tb[TCA_FLOWER_FLAGS]) {
  		fnew->flags = nla_get_u32(tb[TCA_FLOWER_FLAGS]);
  
  		if (!tc_flags_valid(fnew->flags)) {
  			err = -EINVAL;
  			goto errout;
  		}
  	}

  	err = fl_set_parms(net, tp, fnew, &mask, base, tb, tca[TCA_RATE], ovr);
  	if (err)
  		goto errout;
  
  	err = fl_check_assign_mask(head, &mask);
  	if (err)
  		goto errout;

  	if (!tc_skip_sw(fnew->flags)) {

  		err = rhashtable_insert_fast(&head->ht, &fnew->ht_node,
  					     head->ht_params);
  		if (err)
  			goto errout;
  	}

  	err = fl_hw_replace_filter(tp,
  				   &head->dissector,
  				   &mask.key,
  				   &fnew->key,
  				   &fnew->exts,
  				   (unsigned long)fnew,
  				   fnew->flags);
  	if (err)
  		goto errout;

  
  	if (fold) {

  		rhashtable_remove_fast(&head->ht, &fold->ht_node,
  				       head->ht_params);

  		fl_hw_destroy_filter(tp, (unsigned long)fold);

  	}

  
  	*arg = (unsigned long) fnew;
  
  	if (fold) {

  		list_replace_rcu(&fold->list, &fnew->list);

  		tcf_unbind_filter(tp, &fold->res);
  		call_rcu(&fold->rcu, fl_destroy_filter);
  	} else {
  		list_add_tail_rcu(&fnew->list, &head->filters);
  	}
  
  	return 0;
  
  errout:

  	tcf_exts_destroy(&fnew->exts);

  	kfree(fnew);
  	return err;
  }
  
  static int fl_delete(struct tcf_proto *tp, unsigned long arg)
  {
  	struct cls_fl_head *head = rtnl_dereference(tp->root);
  	struct cls_fl_filter *f = (struct cls_fl_filter *) arg;
  
  	rhashtable_remove_fast(&head->ht, &f->ht_node,
  			       head->ht_params);
  	list_del_rcu(&f->list);

  	fl_hw_destroy_filter(tp, (unsigned long)f);

  	tcf_unbind_filter(tp, &f->res);
  	call_rcu(&f->rcu, fl_destroy_filter);
  	return 0;
  }
  
  static void fl_walk(struct tcf_proto *tp, struct tcf_walker *arg)
  {
  	struct cls_fl_head *head = rtnl_dereference(tp->root);
  	struct cls_fl_filter *f;
  
  	list_for_each_entry_rcu(f, &head->filters, list) {
  		if (arg->count < arg->skip)
  			goto skip;
  		if (arg->fn(tp, (unsigned long) f, arg) < 0) {
  			arg->stop = 1;
  			break;
  		}
  skip:
  		arg->count++;
  	}
  }
  
  static int fl_dump_key_val(struct sk_buff *skb,
  			   void *val, int val_type,
  			   void *mask, int mask_type, int len)
  {
  	int err;
  
  	if (!memchr_inv(mask, 0, len))
  		return 0;
  	err = nla_put(skb, val_type, len, val);
  	if (err)
  		return err;
  	if (mask_type != TCA_FLOWER_UNSPEC) {
  		err = nla_put(skb, mask_type, len, mask);
  		if (err)
  			return err;
  	}
  	return 0;
  }

  static int fl_dump_key_vlan(struct sk_buff *skb,
  			    struct flow_dissector_key_vlan *vlan_key,
  			    struct flow_dissector_key_vlan *vlan_mask)
  {
  	int err;
  
  	if (!memchr_inv(vlan_mask, 0, sizeof(*vlan_mask)))
  		return 0;
  	if (vlan_mask->vlan_id) {
  		err = nla_put_u16(skb, TCA_FLOWER_KEY_VLAN_ID,
  				  vlan_key->vlan_id);
  		if (err)
  			return err;
  	}
  	if (vlan_mask->vlan_priority) {
  		err = nla_put_u8(skb, TCA_FLOWER_KEY_VLAN_PRIO,
  				 vlan_key->vlan_priority);
  		if (err)
  			return err;
  	}
  	return 0;
  }

  static int fl_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
  		   struct sk_buff *skb, struct tcmsg *t)
  {
  	struct cls_fl_head *head = rtnl_dereference(tp->root);
  	struct cls_fl_filter *f = (struct cls_fl_filter *) fh;
  	struct nlattr *nest;
  	struct fl_flow_key *key, *mask;
  
  	if (!f)
  		return skb->len;
  
  	t->tcm_handle = f->handle;
  
  	nest = nla_nest_start(skb, TCA_OPTIONS);
  	if (!nest)
  		goto nla_put_failure;
  
  	if (f->res.classid &&
  	    nla_put_u32(skb, TCA_FLOWER_CLASSID, f->res.classid))
  		goto nla_put_failure;
  
  	key = &f->key;
  	mask = &head->mask.key;
  
  	if (mask->indev_ifindex) {
  		struct net_device *dev;
  
  		dev = __dev_get_by_index(net, key->indev_ifindex);
  		if (dev && nla_put_string(skb, TCA_FLOWER_INDEV, dev->name))
  			goto nla_put_failure;
  	}

  	fl_hw_update_stats(tp, f);

  	if (fl_dump_key_val(skb, key->eth.dst, TCA_FLOWER_KEY_ETH_DST,
  			    mask->eth.dst, TCA_FLOWER_KEY_ETH_DST_MASK,
  			    sizeof(key->eth.dst)) ||
  	    fl_dump_key_val(skb, key->eth.src, TCA_FLOWER_KEY_ETH_SRC,
  			    mask->eth.src, TCA_FLOWER_KEY_ETH_SRC_MASK,
  			    sizeof(key->eth.src)) ||
  	    fl_dump_key_val(skb, &key->basic.n_proto, TCA_FLOWER_KEY_ETH_TYPE,
  			    &mask->basic.n_proto, TCA_FLOWER_UNSPEC,
  			    sizeof(key->basic.n_proto)))
  		goto nla_put_failure;

  
  	if (fl_dump_key_vlan(skb, &key->vlan, &mask->vlan))
  		goto nla_put_failure;

  	if ((key->basic.n_proto == htons(ETH_P_IP) ||
  	     key->basic.n_proto == htons(ETH_P_IPV6)) &&
  	    fl_dump_key_val(skb, &key->basic.ip_proto, TCA_FLOWER_KEY_IP_PROTO,
  			    &mask->basic.ip_proto, TCA_FLOWER_UNSPEC,
  			    sizeof(key->basic.ip_proto)))
  		goto nla_put_failure;

  	if (key->control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS &&

  	    (fl_dump_key_val(skb, &key->ipv4.src, TCA_FLOWER_KEY_IPV4_SRC,
  			     &mask->ipv4.src, TCA_FLOWER_KEY_IPV4_SRC_MASK,
  			     sizeof(key->ipv4.src)) ||
  	     fl_dump_key_val(skb, &key->ipv4.dst, TCA_FLOWER_KEY_IPV4_DST,
  			     &mask->ipv4.dst, TCA_FLOWER_KEY_IPV4_DST_MASK,
  			     sizeof(key->ipv4.dst))))
  		goto nla_put_failure;

  	else if (key->control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS &&

  		 (fl_dump_key_val(skb, &key->ipv6.src, TCA_FLOWER_KEY_IPV6_SRC,
  				  &mask->ipv6.src, TCA_FLOWER_KEY_IPV6_SRC_MASK,
  				  sizeof(key->ipv6.src)) ||
  		  fl_dump_key_val(skb, &key->ipv6.dst, TCA_FLOWER_KEY_IPV6_DST,
  				  &mask->ipv6.dst, TCA_FLOWER_KEY_IPV6_DST_MASK,
  				  sizeof(key->ipv6.dst))))
  		goto nla_put_failure;
  
  	if (key->basic.ip_proto == IPPROTO_TCP &&
  	    (fl_dump_key_val(skb, &key->tp.src, TCA_FLOWER_KEY_TCP_SRC,

  			     &mask->tp.src, TCA_FLOWER_KEY_TCP_SRC_MASK,

  			     sizeof(key->tp.src)) ||
  	     fl_dump_key_val(skb, &key->tp.dst, TCA_FLOWER_KEY_TCP_DST,

  			     &mask->tp.dst, TCA_FLOWER_KEY_TCP_DST_MASK,

  			     sizeof(key->tp.dst))))
  		goto nla_put_failure;
  	else if (key->basic.ip_proto == IPPROTO_UDP &&
  		 (fl_dump_key_val(skb, &key->tp.src, TCA_FLOWER_KEY_UDP_SRC,

  				  &mask->tp.src, TCA_FLOWER_KEY_UDP_SRC_MASK,

  				  sizeof(key->tp.src)) ||
  		  fl_dump_key_val(skb, &key->tp.dst, TCA_FLOWER_KEY_UDP_DST,

  				  &mask->tp.dst, TCA_FLOWER_KEY_UDP_DST_MASK,

  				  sizeof(key->tp.dst))))
  		goto nla_put_failure;

  	if (key->enc_control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS &&
  	    (fl_dump_key_val(skb, &key->enc_ipv4.src,
  			    TCA_FLOWER_KEY_ENC_IPV4_SRC, &mask->enc_ipv4.src,
  			    TCA_FLOWER_KEY_ENC_IPV4_SRC_MASK,
  			    sizeof(key->enc_ipv4.src)) ||
  	     fl_dump_key_val(skb, &key->enc_ipv4.dst,
  			     TCA_FLOWER_KEY_ENC_IPV4_DST, &mask->enc_ipv4.dst,
  			     TCA_FLOWER_KEY_ENC_IPV4_DST_MASK,
  			     sizeof(key->enc_ipv4.dst))))
  		goto nla_put_failure;
  	else if (key->enc_control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS &&
  		 (fl_dump_key_val(skb, &key->enc_ipv6.src,
  			    TCA_FLOWER_KEY_ENC_IPV6_SRC, &mask->enc_ipv6.src,
  			    TCA_FLOWER_KEY_ENC_IPV6_SRC_MASK,
  			    sizeof(key->enc_ipv6.src)) ||
  		 fl_dump_key_val(skb, &key->enc_ipv6.dst,
  				 TCA_FLOWER_KEY_ENC_IPV6_DST,
  				 &mask->enc_ipv6.dst,
  				 TCA_FLOWER_KEY_ENC_IPV6_DST_MASK,
  			    sizeof(key->enc_ipv6.dst))))
  		goto nla_put_failure;
  
  	if (fl_dump_key_val(skb, &key->enc_key_id, TCA_FLOWER_KEY_ENC_KEY_ID,

  			    &mask->enc_key_id, TCA_FLOWER_UNSPEC,

  			    sizeof(key->enc_key_id)))
  		goto nla_put_failure;

  	nla_put_u32(skb, TCA_FLOWER_FLAGS, f->flags);

  	if (tcf_exts_dump(skb, &f->exts))
  		goto nla_put_failure;
  
  	nla_nest_end(skb, nest);
  
  	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
  		goto nla_put_failure;
  
  	return skb->len;
  
  nla_put_failure:
  	nla_nest_cancel(skb, nest);
  	return -1;
  }
  
  static struct tcf_proto_ops cls_fl_ops __read_mostly = {
  	.kind		= "flower",
  	.classify	= fl_classify,
  	.init		= fl_init,
  	.destroy	= fl_destroy,
  	.get		= fl_get,
  	.change		= fl_change,
  	.delete		= fl_delete,
  	.walk		= fl_walk,
  	.dump		= fl_dump,
  	.owner		= THIS_MODULE,
  };
  
  static int __init cls_fl_init(void)
  {
  	return register_tcf_proto_ops(&cls_fl_ops);
  }
  
  static void __exit cls_fl_exit(void)
  {
  	unregister_tcf_proto_ops(&cls_fl_ops);
  }
  
  module_init(cls_fl_init);
  module_exit(cls_fl_exit);
  
  MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
  MODULE_DESCRIPTION("Flower classifier");
  MODULE_LICENSE("GPL v2");