kernel/lib/fonts/Kconfig


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#
# Font configuration
#

config FONT_SUPPORT
	tristate

if FONT_SUPPORT

config FONTS
	bool "Select compiled-in fonts"
	depends on FRAMEBUFFER_CONSOLE || STI_CONSOLE
	help
	  Say Y here if you would like to use fonts other than the default
	  your frame buffer console usually use.

	  Note that the answer to this question won't directly affect the
	  kernel: saying N will just cause the configurator to skip all
	  the questions about foreign fonts.

	  If unsure, say N (the default choices are safe).

config FONT_8x8
	bool "VGA 8x8 font" if FONTS
	depends on FRAMEBUFFER_CONSOLE || STI_CONSOLE
	default y if !SPARC && !FONTS
	help
	  This is the "high resolution" font for the VGA frame buffer (the one
	  provided by the text console 80x50 (and higher) modes).

	  Note that this is a poor quality font. The VGA 8x16 font is quite a
	  lot more readable.

	  Given the resolution provided by the frame buffer device, answer N
	  here is safe.

config FONT_8x16
	bool "VGA 8x16 font" if FONTS
	default y if !SPARC && !FONTS
	help
	  This is the "high resolution" font for the VGA frame buffer (the one
	  provided by the VGA text console 80x25 mode.

	  If unsure, say Y.

config FONT_6x11
	bool "Mac console 6x11 font (not supported by all drivers)" if FONTS
	depends on FRAMEBUFFER_CONSOLE || STI_CONSOLE
	default y if !SPARC && !FONTS && MAC
	help
	  Small console font with Macintosh-style high-half glyphs.  Some Mac
	  framebuffer drivers don't support this one at all.

config FONT_7x14
	bool "console 7x14 font (not supported by all drivers)" if FONTS
	depends on FRAMEBUFFER_CONSOLE
	help
	  Console font with characters just a bit smaller than the default.
	  If the standard 8x16 font is a little too big for you, say Y.
	  Otherwise, say N.

config FONT_PEARL_8x8
	bool "Pearl (old m68k) console 8x8 font" if FONTS
	depends on FRAMEBUFFER_CONSOLE
	default y if !SPARC && !FONTS && AMIGA
	help
	  Small console font with PC-style control-character and high-half
	  glyphs.

config FONT_ACORN_8x8
	bool "Acorn console 8x8 font" if FONTS
	depends on FRAMEBUFFER_CONSOLE
	default y if !SPARC && !FONTS && ARM && ARCH_ACORN
	help
	  Small console font with PC-style control characters and high-half
	  glyphs.

config FONT_MINI_4x6
	bool "Mini 4x6 font"
	depends on !SPARC && FONTS

config FONT_6x10
	bool "Medium-size 6x10 font"
	depends on !SPARC && FONTS
	help
	  Medium-size console font. Suitable for framebuffer consoles on
	  embedded devices with a 320x240 screen, to get a reasonable number
	  of characters (53x24) that are still at a readable size.

config FONT_SUN8x16
	bool "Sparc console 8x16 font"
	depends on FRAMEBUFFER_CONSOLE && (!SPARC && FONTS || SPARC)
	help
	  This is the high resolution console font for Sun machines. Say Y.

config FONT_SUN12x22
	bool "Sparc console 12x22 font (not supported by all drivers)"
	depends on FRAMEBUFFER_CONSOLE && (!SPARC && FONTS || SPARC)
	help
	  This is the high resolution console font for Sun machines with very
	  big letters (like the letters used in the SPARC PROM). If the
	  standard font is unreadable for you, say Y, otherwise say N.

config FONT_10x18
	bool "console 10x18 font (not supported by all drivers)" if FONTS
	depends on FRAMEBUFFER_CONSOLE
	help
	  This is a high resolution console font for machines with very
	  big letters. It fits between the sun 12x22 and the normal 8x16 font.
	  If other fonts are too big or too small for you, say Y, otherwise say N.

config FONT_AUTOSELECT
	def_bool y
	depends on !FONT_8x8
	depends on !FONT_6x11
	depends on !FONT_7x14
	depends on !FONT_PEARL_8x8
	depends on !FONT_ACORN_8x8
	depends on !FONT_MINI_4x6
	depends on !FONT_6x10
	depends on !FONT_SUN8x16
	depends on !FONT_SUN12x22
	depends on !FONT_10x18
	select FONT_8x16

endif # FONT_SUPPORT
/*
 * Copyright (c) 2015 Nicira, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 */

#include <linux/module.h>
#include <linux/openvswitch.h>
#include <net/ip.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_labels.h>
#include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/ipv6/nf_defrag_ipv6.h>

#include "datapath.h"
#include "conntrack.h"
#include "flow.h"
#include "flow_netlink.h"

struct ovs_ct_len_tbl {
	size_t maxlen;
	size_t minlen;
};

/* Metadata mark for masked write to conntrack mark */
struct md_mark {
	u32 value;
	u32 mask;
};

/* Metadata label for masked write to conntrack label. */
struct md_labels {
	struct ovs_key_ct_labels value;
	struct ovs_key_ct_labels mask;
};

/* Conntrack action context for execution. */
struct ovs_conntrack_info {
	struct nf_conntrack_helper *helper;
	struct nf_conntrack_zone zone;
	struct nf_conn *ct;
	u8 commit : 1;
	u16 family;
	struct md_mark mark;
	struct md_labels labels;
};

static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);

static u16 key_to_nfproto(const struct sw_flow_key *key)
{
	switch (ntohs(key->eth.type)) {
	case ETH_P_IP:
		return NFPROTO_IPV4;
	case ETH_P_IPV6:
		return NFPROTO_IPV6;
	default:
		return NFPROTO_UNSPEC;
	}
}

/* Map SKB connection state into the values used by flow definition. */
static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo)
{
	u8 ct_state = OVS_CS_F_TRACKED;

	switch (ctinfo) {
	case IP_CT_ESTABLISHED_REPLY:
	case IP_CT_RELATED_REPLY:
	case IP_CT_NEW_REPLY:
		ct_state |= OVS_CS_F_REPLY_DIR;
		break;
	default:
		break;
	}

	switch (ctinfo) {
	case IP_CT_ESTABLISHED:
	case IP_CT_ESTABLISHED_REPLY:
		ct_state |= OVS_CS_F_ESTABLISHED;
		break;
	case IP_CT_RELATED:
	case IP_CT_RELATED_REPLY:
		ct_state |= OVS_CS_F_RELATED;
		break;
	case IP_CT_NEW:
	case IP_CT_NEW_REPLY:
		ct_state |= OVS_CS_F_NEW;
		break;
	default:
		break;
	}

	return ct_state;
}

static u32 ovs_ct_get_mark(const struct nf_conn *ct)
{
#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
	return ct ? ct->mark : 0;
#else
	return 0;
#endif
}

static void ovs_ct_get_labels(const struct nf_conn *ct,
			      struct ovs_key_ct_labels *labels)
{
	struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL;

	if (cl) {
		size_t len = cl->words * sizeof(long);

		if (len > OVS_CT_LABELS_LEN)
			len = OVS_CT_LABELS_LEN;
		else if (len < OVS_CT_LABELS_LEN)
			memset(labels, 0, OVS_CT_LABELS_LEN);
		memcpy(labels, cl->bits, len);
	} else {
		memset(labels, 0, OVS_CT_LABELS_LEN);
	}
}

static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state,
				const struct nf_conntrack_zone *zone,
				const struct nf_conn *ct)
{
	key->ct.state = state;
	key->ct.zone = zone->id;
	key->ct.mark = ovs_ct_get_mark(ct);
	ovs_ct_get_labels(ct, &key->ct.labels);
}

/* Update 'key' based on skb->nfct. If 'post_ct' is true, then OVS has
 * previously sent the packet to conntrack via the ct action.
 */
static void ovs_ct_update_key(const struct sk_buff *skb,
			      const struct ovs_conntrack_info *info,
			      struct sw_flow_key *key, bool post_ct)
{
	const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt;
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct;
	u8 state = 0;

	ct = nf_ct_get(skb, &ctinfo);
	if (ct) {
		state = ovs_ct_get_state(ctinfo);
		if (!nf_ct_is_confirmed(ct))
			state |= OVS_CS_F_NEW;
		if (ct->master)
			state |= OVS_CS_F_RELATED;
		zone = nf_ct_zone(ct);
	} else if (post_ct) {
		state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID;
		if (info)
			zone = &info->zone;
	}
	__ovs_ct_update_key(key, state, zone, ct);
}

void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key)
{
	ovs_ct_update_key(skb, NULL, key, false);
}

int ovs_ct_put_key(const struct sw_flow_key *key, struct sk_buff *skb)
{
	if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, key->ct.state))
		return -EMSGSIZE;

	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
	    nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, key->ct.zone))
		return -EMSGSIZE;

	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
	    nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, key->ct.mark))
		return -EMSGSIZE;

	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
	    nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(key->ct.labels),
		    &key->ct.labels))
		return -EMSGSIZE;

	return 0;
}

static int ovs_ct_set_mark(struct sk_buff *skb, struct sw_flow_key *key,
			   u32 ct_mark, u32 mask)
{
#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct;
	u32 new_mark;


	/* The connection could be invalid, in which case set_mark is no-op. */
	ct = nf_ct_get(skb, &ctinfo);
	if (!ct)
		return 0;

	new_mark = ct_mark | (ct->mark & ~(mask));
	if (ct->mark != new_mark) {
		ct->mark = new_mark;
		nf_conntrack_event_cache(IPCT_MARK, ct);
		key->ct.mark = new_mark;
	}

	return 0;
#else
	return -ENOTSUPP;
#endif
}

static int ovs_ct_set_labels(struct sk_buff *skb, struct sw_flow_key *key,
			     const struct ovs_key_ct_labels *labels,
			     const struct ovs_key_ct_labels *mask)
{
	enum ip_conntrack_info ctinfo;
	struct nf_conn_labels *cl;
	struct nf_conn *ct;
	int err;

	/* The connection could be invalid, in which case set_label is no-op.*/
	ct = nf_ct_get(skb, &ctinfo);
	if (!ct)
		return 0;

	cl = nf_ct_labels_find(ct);
	if (!cl) {
		nf_ct_labels_ext_add(ct);
		cl = nf_ct_labels_find(ct);
	}
	if (!cl || cl->words * sizeof(long) < OVS_CT_LABELS_LEN)
		return -ENOSPC;

	err = nf_connlabels_replace(ct, (u32 *)labels, (u32 *)mask,
				    OVS_CT_LABELS_LEN / sizeof(u32));
	if (err)
		return err;

	ovs_ct_get_labels(ct, &key->ct.labels);
	return 0;
}

/* 'skb' should already be pulled to nh_ofs. */
static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
{
	const struct nf_conntrack_helper *helper;
	const struct nf_conn_help *help;
	enum ip_conntrack_info ctinfo;
	unsigned int protoff;
	struct nf_conn *ct;

	ct = nf_ct_get(skb, &ctinfo);
	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
		return NF_ACCEPT;

	help = nfct_help(ct);
	if (!help)
		return NF_ACCEPT;

	helper = rcu_dereference(help->helper);
	if (!helper)
		return NF_ACCEPT;

	switch (proto) {
	case NFPROTO_IPV4:
		protoff = ip_hdrlen(skb);
		break;
	case NFPROTO_IPV6: {
		u8 nexthdr = ipv6_hdr(skb)->nexthdr;
		__be16 frag_off;
		int ofs;

		ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
				       &frag_off);
		if (ofs < 0 || (frag_off & htons(~0x7)) != 0) {
			pr_debug("proto header not found\n");
			return NF_ACCEPT;
		}
		protoff = ofs;
		break;
	}
	default:
		WARN_ONCE(1, "helper invoked on non-IP family!");
		return NF_DROP;
	}

	return helper->help(skb, protoff, ct, ctinfo);
}

/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
 * value if 'skb' is freed.
 */
static int handle_fragments(struct net *net, struct sw_flow_key *key,
			    u16 zone, struct sk_buff *skb)
{
	struct ovs_skb_cb ovs_cb = *OVS_CB(skb);

	if (key->eth.type == htons(ETH_P_IP)) {
		enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
		int err;

		memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
		err = ip_defrag(net, skb, user);
		if (err)
			return err;

		ovs_cb.mru = IPCB(skb)->frag_max_size;
#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
	} else if (key->eth.type == htons(ETH_P_IPV6)) {
		enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
		struct sk_buff *reasm;

		memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
		reasm = nf_ct_frag6_gather(net, skb, user);
		if (!reasm)
			return -EINPROGRESS;

		if (skb == reasm) {
			kfree_skb(skb);
			return -EINVAL;
		}

		/* Don't free 'skb' even though it is one of the original
		 * fragments, as we're going to morph it into the head.
		 */
		skb_get(skb);
		nf_ct_frag6_consume_orig(reasm);

		key->ip.proto = ipv6_hdr(reasm)->nexthdr;
		skb_morph(skb, reasm);
		skb->next = reasm->next;
		consume_skb(reasm);
		ovs_cb.mru = IP6CB(skb)->frag_max_size;
#endif
	} else {
		kfree_skb(skb);
		return -EPFNOSUPPORT;
	}

	key->ip.frag = OVS_FRAG_TYPE_NONE;
	skb_clear_hash(skb);
	skb->ignore_df = 1;
	*OVS_CB(skb) = ovs_cb;

	return 0;
}

static struct nf_conntrack_expect *
ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone,
		   u16 proto, const struct sk_buff *skb)
{
	struct nf_conntrack_tuple tuple;

	if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple))
		return NULL;
	return __nf_ct_expect_find(net, zone, &tuple);
}

/* Determine whether skb->nfct is equal to the result of conntrack lookup. */
static bool skb_nfct_cached(const struct net *net, const struct sk_buff *skb,
			    const struct ovs_conntrack_info *info)
{
	enum ip_conntrack_info ctinfo;
	struct nf_conn *ct;

	ct = nf_ct_get(skb, &ctinfo);
	if (!ct)
		return false;
	if (!net_eq(net, read_pnet(&ct->ct_net)))
		return false;
	if (!nf_ct_zone_equal_any(info->ct, nf_ct_zone(ct)))
		return false;
	if (info->helper) {
		struct nf_conn_help *help;

		help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
		if (help && rcu_access_pointer(help->helper) != info->helper)
			return false;
	}

	return true;
}

static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
			   const struct ovs_conntrack_info *info,
			   struct sk_buff *skb)
{
	/* If we are recirculating packets to match on conntrack fields and
	 * committing with a separate conntrack action,  then we don't need to
	 * actually run the packet through conntrack twice unless it's for a
	 * different zone.
	 */
	if (!skb_nfct_cached(net, skb, info)) {
		struct nf_conn *tmpl = info->ct;

		/* Associate skb with specified zone. */
		if (tmpl) {
			if (skb->nfct)
				nf_conntrack_put(skb->nfct);
			nf_conntrack_get(&tmpl->ct_general);
			skb->nfct = &tmpl->ct_general;
			skb->nfctinfo = IP_CT_NEW;
		}

		if (nf_conntrack_in(net, info->family, NF_INET_PRE_ROUTING,
				    skb) != NF_ACCEPT)
			return -ENOENT;

		if (ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
			WARN_ONCE(1, "helper rejected packet");
			return -EINVAL;
		}
	}

	ovs_ct_update_key(skb, info, key, true);

	return 0;
}

/* Lookup connection and read fields into key. */
static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
			 const struct ovs_conntrack_info *info,
			 struct sk_buff *skb)
{
	struct nf_conntrack_expect *exp;

	exp = ovs_ct_expect_find(net, &info->zone, info->family, skb);
	if (exp) {
		u8 state;

		state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
		__ovs_ct_update_key(key, state, &info->zone, exp->master);
	} else {
		int err;

		err = __ovs_ct_lookup(net, key, info, skb);
		if (err)
			return err;
	}

	return 0;
}

/* Lookup connection and confirm if unconfirmed. */
static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
			 const struct ovs_conntrack_info *info,
			 struct sk_buff *skb)
{
	u8 state;
	int err;

	state = key->ct.state;
	if (key->ct.zone == info->zone.id &&
	    ((state & OVS_CS_F_TRACKED) && !(state & OVS_CS_F_NEW))) {
		/* Previous lookup has shown that this connection is already
		 * tracked and committed. Skip committing.
		 */
		return 0;
	}

	err = __ovs_ct_lookup(net, key, info, skb);
	if (err)
		return err;
	if (nf_conntrack_confirm(skb) != NF_ACCEPT)
		return -EINVAL;

	return 0;
}

static bool labels_nonzero(const struct ovs_key_ct_labels *labels)
{
	size_t i;

	for (i = 0; i < sizeof(*labels); i++)
		if (labels->ct_labels[i])
			return true;

	return false;
}

/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
 * value if 'skb' is freed.
 */
int ovs_ct_execute(struct net *net, struct sk_buff *skb,
		   struct sw_flow_key *key,
		   const struct ovs_conntrack_info *info)
{
	int nh_ofs;
	int err;

	/* The conntrack module expects to be working at L3. */
	nh_ofs = skb_network_offset(skb);
	skb_pull(skb, nh_ofs);

	if (key->ip.frag != OVS_FRAG_TYPE_NONE) {
		err = handle_fragments(net, key, info->zone.id, skb);
		if (err)
			return err;
	}

	if (info->commit)
		err = ovs_ct_commit(net, key, info, skb);
	else
		err = ovs_ct_lookup(net, key, info, skb);
	if (err)
		goto err;

	if (info->mark.mask) {
		err = ovs_ct_set_mark(skb, key, info->mark.value,
				      info->mark.mask);
		if (err)
			goto err;
	}
	if (labels_nonzero(&info->labels.mask))
		err = ovs_ct_set_labels(skb, key, &info->labels.value,
					&info->labels.mask);
err:
	skb_push(skb, nh_ofs);
	if (err)
		kfree_skb(skb);
	return err;
}

static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
			     const struct sw_flow_key *key, bool log)
{
	struct nf_conntrack_helper *helper;
	struct nf_conn_help *help;

	helper = nf_conntrack_helper_try_module_get(name, info->family,
						    key->ip.proto);
	if (!helper) {
		OVS_NLERR(log, "Unknown helper \"%s\"", name);
		return -EINVAL;
	}

	help = nf_ct_helper_ext_add(info->ct, helper, GFP_KERNEL);
	if (!help) {
		module_put(helper->me);
		return -ENOMEM;
	}

	rcu_assign_pointer(help->helper, helper);
	info->helper = helper;
	return 0;
}

static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
	[OVS_CT_ATTR_COMMIT]	= { .minlen = 0, .maxlen = 0 },
	[OVS_CT_ATTR_ZONE]	= { .minlen = sizeof(u16),
				    .maxlen = sizeof(u16) },
	[OVS_CT_ATTR_MARK]	= { .minlen = sizeof(struct md_mark),
				    .maxlen = sizeof(struct md_mark) },
	[OVS_CT_ATTR_LABELS]	= { .minlen = sizeof(struct md_labels),
				    .maxlen = sizeof(struct md_labels) },
	[OVS_CT_ATTR_HELPER]	= { .minlen = 1,
				    .maxlen = NF_CT_HELPER_NAME_LEN }
};

static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
		    const char **helper, bool log)
{
	struct nlattr *a;
	int rem;

	nla_for_each_nested(a, attr, rem) {
		int type = nla_type(a);
		int maxlen = ovs_ct_attr_lens[type].maxlen;
		int minlen = ovs_ct_attr_lens[type].minlen;

		if (type > OVS_CT_ATTR_MAX) {
			OVS_NLERR(log,
				  "Unknown conntrack attr (type=%d, max=%d)",
				  type, OVS_CT_ATTR_MAX);
			return -EINVAL;
		}
		if (nla_len(a) < minlen || nla_len(a) > maxlen) {
			OVS_NLERR(log,
				  "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)",
				  type, nla_len(a), maxlen);
			return -EINVAL;
		}

		switch (type) {
		case OVS_CT_ATTR_COMMIT:
			info->commit = true;
			break;
#ifdef CONFIG_NF_CONNTRACK_ZONES
		case OVS_CT_ATTR_ZONE:
			info->zone.id = nla_get_u16(a);
			break;
#endif
#ifdef CONFIG_NF_CONNTRACK_MARK
		case OVS_CT_ATTR_MARK: {
			struct md_mark *mark = nla_data(a);

			if (!mark->mask) {
				OVS_NLERR(log, "ct_mark mask cannot be 0");
				return -EINVAL;
			}
			info->mark = *mark;
			break;
		}
#endif
#ifdef CONFIG_NF_CONNTRACK_LABELS
		case OVS_CT_ATTR_LABELS: {
			struct md_labels *labels = nla_data(a);

			if (!labels_nonzero(&labels->mask)) {
				OVS_NLERR(log, "ct_labels mask cannot be 0");
				return -EINVAL;
			}
			info->labels = *labels;
			break;
		}
#endif
		case OVS_CT_ATTR_HELPER:
			*helper = nla_data(a);
			if (!memchr(*helper, '\0', nla_len(a))) {
				OVS_NLERR(log, "Invalid conntrack helper");
				return -EINVAL;
			}
			break;
		default:
			OVS_NLERR(log, "Unknown conntrack attr (%d)",
				  type);
			return -EINVAL;
		}
	}

	if (rem > 0) {
		OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem);
		return -EINVAL;
	}

	return 0;
}

bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr)
{
	if (attr == OVS_KEY_ATTR_CT_STATE)
		return true;
	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
	    attr == OVS_KEY_ATTR_CT_ZONE)
		return true;
	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
	    attr == OVS_KEY_ATTR_CT_MARK)
		return true;
	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
	    attr == OVS_KEY_ATTR_CT_LABELS) {
		struct ovs_net *ovs_net = net_generic(net, ovs_net_id);

		return ovs_net->xt_label;
	}

	return false;
}

int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
		       const struct sw_flow_key *key,
		       struct sw_flow_actions **sfa,  bool log)
{
	struct ovs_conntrack_info ct_info;
	const char *helper = NULL;
	u16 family;
	int err;

	family = key_to_nfproto(key);
	if (family == NFPROTO_UNSPEC) {
		OVS_NLERR(log, "ct family unspecified");
		return -EINVAL;
	}

	memset(&ct_info, 0, sizeof(ct_info));
	ct_info.family = family;

	nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID,
			NF_CT_DEFAULT_ZONE_DIR, 0);

	err = parse_ct(attr, &ct_info, &helper, log);
	if (err)
		return err;

	/* Set up template for tracking connections in specific zones. */
	ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL);
	if (!ct_info.ct) {
		OVS_NLERR(log, "Failed to allocate conntrack template");
		return -ENOMEM;
	}

	__set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
	nf_conntrack_get(&ct_info.ct->ct_general);

	if (helper) {
		err = ovs_ct_add_helper(&ct_info, helper, key, log);
		if (err)
			goto err_free_ct;
	}

	err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info,
				 sizeof(ct_info), log);
	if (err)
		goto err_free_ct;

	return 0;
err_free_ct:
	__ovs_ct_free_action(&ct_info);
	return err;
}

int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
			  struct sk_buff *skb)
{
	struct nlattr *start;

	start = nla_nest_start(skb, OVS_ACTION_ATTR_CT);
	if (!start)
		return -EMSGSIZE;

	if (ct_info->commit && nla_put_flag(skb, OVS_CT_ATTR_COMMIT))
		return -EMSGSIZE;
	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
	    nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id))
		return -EMSGSIZE;
	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask &&
	    nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark),
		    &ct_info->mark))
		return -EMSGSIZE;
	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
	    labels_nonzero(&ct_info->labels.mask) &&
	    nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels),
		    &ct_info->labels))
		return -EMSGSIZE;
	if (ct_info->helper) {
		if (nla_put_string(skb, OVS_CT_ATTR_HELPER,
				   ct_info->helper->name))
			return -EMSGSIZE;
	}

	nla_nest_end(skb, start);

	return 0;
}

void ovs_ct_free_action(const struct nlattr *a)
{
	struct ovs_conntrack_info *ct_info = nla_data(a);

	__ovs_ct_free_action(ct_info);
}

static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info)
{
	if (ct_info->helper)
		module_put(ct_info->helper->me);
	if (ct_info->ct)
		nf_ct_put(ct_info->ct);
}

void ovs_ct_init(struct net *net)
{
	unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE;
	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);

	if (nf_connlabels_get(net, n_bits)) {
		ovs_net->xt_label = false;
		OVS_NLERR(true, "Failed to set connlabel length");
	} else {
		ovs_net->xt_label = true;
	}
}

void ovs_ct_exit(struct net *net)
{
	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);

	if (ovs_net->xt_label)
		nf_connlabels_put(net);
}