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nft_ct.c
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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
*
* Development of this code funded by Astaro AG (http://www.astaro.com/)
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_core.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_acct.h>
#include <net/netfilter/nf_conntrack_tuple.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_ecache.h>
#include <net/netfilter/nf_conntrack_labels.h>
#include <net/netfilter/nf_conntrack_timeout.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_expect.h>
struct nft_ct_helper_obj {
struct nf_conntrack_helper *helper4;
struct nf_conntrack_helper *helper6;
u8 l4proto;
};
#ifdef CONFIG_NF_CONNTRACK_ZONES
static DEFINE_PER_CPU(struct nf_conn *, nft_ct_pcpu_template);
static unsigned int nft_ct_pcpu_template_refcnt __read_mostly;
static DEFINE_MUTEX(nft_ct_pcpu_mutex);
#endif
static u64 nft_ct_get_eval_counter(const struct nf_conn_counter *c,
enum nft_ct_keys k,
enum ip_conntrack_dir d)
{
if (d < IP_CT_DIR_MAX)
return k == NFT_CT_BYTES ? atomic64_read(&c[d].bytes) :
atomic64_read(&c[d].packets);
return nft_ct_get_eval_counter(c, k, IP_CT_DIR_ORIGINAL) +
nft_ct_get_eval_counter(c, k, IP_CT_DIR_REPLY);
}
static void nft_ct_get_eval(const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
const struct nft_ct *priv = nft_expr_priv(expr);
u32 *dest = ®s->data[priv->dreg];
enum ip_conntrack_info ctinfo;
const struct nf_conn *ct;
const struct nf_conn_help *help;
const struct nf_conntrack_tuple *tuple;
const struct nf_conntrack_helper *helper;
unsigned int state;
ct = nf_ct_get(pkt->skb, &ctinfo);
switch (priv->key) {
case NFT_CT_STATE:
if (ct)
state = NF_CT_STATE_BIT(ctinfo);
else if (ctinfo == IP_CT_UNTRACKED)
state = NF_CT_STATE_UNTRACKED_BIT;
else
state = NF_CT_STATE_INVALID_BIT;
*dest = state;
return;
default:
break;
}
if (ct == NULL)
goto err;
switch (priv->key) {
case NFT_CT_DIRECTION:
nft_reg_store8(dest, CTINFO2DIR(ctinfo));
return;
case NFT_CT_STATUS:
*dest = ct->status;
return;
#ifdef CONFIG_NF_CONNTRACK_MARK
case NFT_CT_MARK:
*dest = READ_ONCE(ct->mark);
return;
#endif
#ifdef CONFIG_NF_CONNTRACK_SECMARK
case NFT_CT_SECMARK:
*dest = ct->secmark;
return;
#endif
case NFT_CT_EXPIRATION:
*dest = jiffies_to_msecs(nf_ct_expires(ct));
return;
case NFT_CT_HELPER:
if (ct->master == NULL)
goto err;
help = nfct_help(ct->master);
if (help == NULL)
goto err;
helper = rcu_dereference(help->helper);
if (helper == NULL)
goto err;
strscpy_pad((char *)dest, helper->name, NF_CT_HELPER_NAME_LEN);
return;
#ifdef CONFIG_NF_CONNTRACK_LABELS
case NFT_CT_LABELS: {
struct nf_conn_labels *labels = nf_ct_labels_find(ct);
if (labels)
memcpy(dest, labels->bits, NF_CT_LABELS_MAX_SIZE);
else
memset(dest, 0, NF_CT_LABELS_MAX_SIZE);
return;
}
#endif
case NFT_CT_BYTES:
case NFT_CT_PKTS: {
const struct nf_conn_acct *acct = nf_conn_acct_find(ct);
u64 count = 0;
if (acct)
count = nft_ct_get_eval_counter(acct->counter,
priv->key, priv->dir);
memcpy(dest, &count, sizeof(count));
return;
}
case NFT_CT_AVGPKT: {
const struct nf_conn_acct *acct = nf_conn_acct_find(ct);
u64 avgcnt = 0, bcnt = 0, pcnt = 0;
if (acct) {
pcnt = nft_ct_get_eval_counter(acct->counter,
NFT_CT_PKTS, priv->dir);
bcnt = nft_ct_get_eval_counter(acct->counter,
NFT_CT_BYTES, priv->dir);
if (pcnt != 0)
avgcnt = div64_u64(bcnt, pcnt);
}
memcpy(dest, &avgcnt, sizeof(avgcnt));
return;
}
case NFT_CT_L3PROTOCOL:
nft_reg_store8(dest, nf_ct_l3num(ct));
return;
case NFT_CT_PROTOCOL:
nft_reg_store8(dest, nf_ct_protonum(ct));
return;
#ifdef CONFIG_NF_CONNTRACK_ZONES
case NFT_CT_ZONE: {
const struct nf_conntrack_zone *zone = nf_ct_zone(ct);
u16 zoneid;
if (priv->dir < IP_CT_DIR_MAX)
zoneid = nf_ct_zone_id(zone, priv->dir);
else
zoneid = zone->id;
nft_reg_store16(dest, zoneid);
return;
}
#endif
case NFT_CT_ID:
*dest = nf_ct_get_id(ct);
return;
default:
break;
}
tuple = &ct->tuplehash[priv->dir].tuple;
switch (priv->key) {
case NFT_CT_SRC:
memcpy(dest, tuple->src.u3.all,
nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16);
return;
case NFT_CT_DST:
memcpy(dest, tuple->dst.u3.all,
nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16);
return;
case NFT_CT_PROTO_SRC:
nft_reg_store16(dest, (__force u16)tuple->src.u.all);
return;
case NFT_CT_PROTO_DST:
nft_reg_store16(dest, (__force u16)tuple->dst.u.all);
return;
case NFT_CT_SRC_IP:
if (nf_ct_l3num(ct) != NFPROTO_IPV4)
goto err;
*dest = (__force __u32)tuple->src.u3.ip;
return;
case NFT_CT_DST_IP:
if (nf_ct_l3num(ct) != NFPROTO_IPV4)
goto err;
*dest = (__force __u32)tuple->dst.u3.ip;
return;
case NFT_CT_SRC_IP6:
if (nf_ct_l3num(ct) != NFPROTO_IPV6)
goto err;
memcpy(dest, tuple->src.u3.ip6, sizeof(struct in6_addr));
return;
case NFT_CT_DST_IP6:
if (nf_ct_l3num(ct) != NFPROTO_IPV6)
goto err;
memcpy(dest, tuple->dst.u3.ip6, sizeof(struct in6_addr));
return;
default:
break;
}
return;
err:
regs->verdict.code = NFT_BREAK;
}
#ifdef CONFIG_NF_CONNTRACK_ZONES
static void nft_ct_set_zone_eval(const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
struct nf_conntrack_zone zone = { .dir = NF_CT_DEFAULT_ZONE_DIR };
const struct nft_ct *priv = nft_expr_priv(expr);
struct sk_buff *skb = pkt->skb;
enum ip_conntrack_info ctinfo;
u16 value = nft_reg_load16(®s->data[priv->sreg]);
struct nf_conn *ct;
ct = nf_ct_get(skb, &ctinfo);
if (ct) /* already tracked */
return;
zone.id = value;
switch (priv->dir) {
case IP_CT_DIR_ORIGINAL:
zone.dir = NF_CT_ZONE_DIR_ORIG;
break;
case IP_CT_DIR_REPLY:
zone.dir = NF_CT_ZONE_DIR_REPL;
break;
default:
break;
}
ct = this_cpu_read(nft_ct_pcpu_template);
if (likely(refcount_read(&ct->ct_general.use) == 1)) {
refcount_inc(&ct->ct_general.use);
nf_ct_zone_add(ct, &zone);
} else {
/* previous skb got queued to userspace, allocate temporary
* one until percpu template can be reused.
*/
ct = nf_ct_tmpl_alloc(nft_net(pkt), &zone, GFP_ATOMIC);
if (!ct) {
regs->verdict.code = NF_DROP;
return;
}
__set_bit(IPS_CONFIRMED_BIT, &ct->status);
}
nf_ct_set(skb, ct, IP_CT_NEW);
}
#endif
static void nft_ct_set_eval(const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
const struct nft_ct *priv = nft_expr_priv(expr);
struct sk_buff *skb = pkt->skb;
#if defined(CONFIG_NF_CONNTRACK_MARK) || defined(CONFIG_NF_CONNTRACK_SECMARK)
u32 value = regs->data[priv->sreg];
#endif
enum ip_conntrack_info ctinfo;
struct nf_conn *ct;
ct = nf_ct_get(skb, &ctinfo);
if (ct == NULL || nf_ct_is_template(ct))
return;
switch (priv->key) {
#ifdef CONFIG_NF_CONNTRACK_MARK
case NFT_CT_MARK:
if (READ_ONCE(ct->mark) != value) {
WRITE_ONCE(ct->mark, value);
nf_conntrack_event_cache(IPCT_MARK, ct);
}
break;
#endif
#ifdef CONFIG_NF_CONNTRACK_SECMARK
case NFT_CT_SECMARK:
if (ct->secmark != value) {
ct->secmark = value;
nf_conntrack_event_cache(IPCT_SECMARK, ct);
}
break;
#endif
#ifdef CONFIG_NF_CONNTRACK_LABELS
case NFT_CT_LABELS:
nf_connlabels_replace(ct,
®s->data[priv->sreg],
®s->data[priv->sreg],
NF_CT_LABELS_MAX_SIZE / sizeof(u32));
break;
#endif
#ifdef CONFIG_NF_CONNTRACK_EVENTS
case NFT_CT_EVENTMASK: {
struct nf_conntrack_ecache *e = nf_ct_ecache_find(ct);
u32 ctmask = regs->data[priv->sreg];
if (e) {
if (e->ctmask != ctmask)
e->ctmask = ctmask;
break;
}
if (ctmask && !nf_ct_is_confirmed(ct))
nf_ct_ecache_ext_add(ct, ctmask, 0, GFP_ATOMIC);
break;
}
#endif
default:
break;
}
}
static const struct nla_policy nft_ct_policy[NFTA_CT_MAX + 1] = {
[NFTA_CT_DREG] = { .type = NLA_U32 },
[NFTA_CT_KEY] = NLA_POLICY_MAX(NLA_BE32, 255),
[NFTA_CT_DIRECTION] = { .type = NLA_U8 },
[NFTA_CT_SREG] = { .type = NLA_U32 },
};
#ifdef CONFIG_NF_CONNTRACK_ZONES
static void nft_ct_tmpl_put_pcpu(void)
{
struct nf_conn *ct;
int cpu;
for_each_possible_cpu(cpu) {
ct = per_cpu(nft_ct_pcpu_template, cpu);
if (!ct)
break;
nf_ct_put(ct);
per_cpu(nft_ct_pcpu_template, cpu) = NULL;
}
}
static bool nft_ct_tmpl_alloc_pcpu(void)
{
struct nf_conntrack_zone zone = { .id = 0 };
struct nf_conn *tmp;
int cpu;
if (nft_ct_pcpu_template_refcnt)
return true;
for_each_possible_cpu(cpu) {
tmp = nf_ct_tmpl_alloc(&init_net, &zone, GFP_KERNEL);
if (!tmp) {
nft_ct_tmpl_put_pcpu();
return false;
}
__set_bit(IPS_CONFIRMED_BIT, &tmp->status);
per_cpu(nft_ct_pcpu_template, cpu) = tmp;
}
return true;
}
#endif
static int nft_ct_get_init(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[])
{
struct nft_ct *priv = nft_expr_priv(expr);
unsigned int len;
int err;
priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
priv->dir = IP_CT_DIR_MAX;
switch (priv->key) {
case NFT_CT_DIRECTION:
if (tb[NFTA_CT_DIRECTION] != NULL)
return -EINVAL;
len = sizeof(u8);
break;
case NFT_CT_STATE:
case NFT_CT_STATUS:
#ifdef CONFIG_NF_CONNTRACK_MARK
case NFT_CT_MARK:
#endif
#ifdef CONFIG_NF_CONNTRACK_SECMARK
case NFT_CT_SECMARK:
#endif
case NFT_CT_EXPIRATION:
if (tb[NFTA_CT_DIRECTION] != NULL)
return -EINVAL;
len = sizeof(u32);
break;
#ifdef CONFIG_NF_CONNTRACK_LABELS
case NFT_CT_LABELS:
if (tb[NFTA_CT_DIRECTION] != NULL)
return -EINVAL;
len = NF_CT_LABELS_MAX_SIZE;
break;
#endif
case NFT_CT_HELPER:
if (tb[NFTA_CT_DIRECTION] != NULL)
return -EINVAL;
len = NF_CT_HELPER_NAME_LEN;
break;
case NFT_CT_L3PROTOCOL:
case NFT_CT_PROTOCOL:
/* For compatibility, do not report error if NFTA_CT_DIRECTION
* attribute is specified.
*/
len = sizeof(u8);
break;
case NFT_CT_SRC:
case NFT_CT_DST:
if (tb[NFTA_CT_DIRECTION] == NULL)
return -EINVAL;
switch (ctx->family) {
case NFPROTO_IPV4:
len = sizeof_field(struct nf_conntrack_tuple,
src.u3.ip);
break;
case NFPROTO_IPV6:
case NFPROTO_INET:
len = sizeof_field(struct nf_conntrack_tuple,
src.u3.ip6);
break;
default:
return -EAFNOSUPPORT;
}
break;
case NFT_CT_SRC_IP:
case NFT_CT_DST_IP:
if (tb[NFTA_CT_DIRECTION] == NULL)
return -EINVAL;
len = sizeof_field(struct nf_conntrack_tuple, src.u3.ip);
break;
case NFT_CT_SRC_IP6:
case NFT_CT_DST_IP6:
if (tb[NFTA_CT_DIRECTION] == NULL)
return -EINVAL;
len = sizeof_field(struct nf_conntrack_tuple, src.u3.ip6);
break;
case NFT_CT_PROTO_SRC:
case NFT_CT_PROTO_DST:
if (tb[NFTA_CT_DIRECTION] == NULL)
return -EINVAL;
len = sizeof_field(struct nf_conntrack_tuple, src.u.all);
break;
case NFT_CT_BYTES:
case NFT_CT_PKTS:
case NFT_CT_AVGPKT:
len = sizeof(u64);
break;
#ifdef CONFIG_NF_CONNTRACK_ZONES
case NFT_CT_ZONE:
len = sizeof(u16);
break;
#endif
case NFT_CT_ID:
if (tb[NFTA_CT_DIRECTION])
return -EINVAL;
len = sizeof(u32);
break;
default:
return -EOPNOTSUPP;
}
if (tb[NFTA_CT_DIRECTION] != NULL) {
priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]);
switch (priv->dir) {
case IP_CT_DIR_ORIGINAL:
case IP_CT_DIR_REPLY:
break;
default:
return -EINVAL;
}
}
priv->len = len;
err = nft_parse_register_store(ctx, tb[NFTA_CT_DREG], &priv->dreg, NULL,
NFT_DATA_VALUE, len);
if (err < 0)
return err;
err = nf_ct_netns_get(ctx->net, ctx->family);
if (err < 0)
return err;
if (priv->key == NFT_CT_BYTES ||
priv->key == NFT_CT_PKTS ||
priv->key == NFT_CT_AVGPKT)
nf_ct_set_acct(ctx->net, true);
return 0;
}
static void __nft_ct_set_destroy(const struct nft_ctx *ctx, struct nft_ct *priv)
{
switch (priv->key) {
#ifdef CONFIG_NF_CONNTRACK_LABELS
case NFT_CT_LABELS:
nf_connlabels_put(ctx->net);
break;
#endif
#ifdef CONFIG_NF_CONNTRACK_ZONES
case NFT_CT_ZONE:
mutex_lock(&nft_ct_pcpu_mutex);
if (--nft_ct_pcpu_template_refcnt == 0)
nft_ct_tmpl_put_pcpu();
mutex_unlock(&nft_ct_pcpu_mutex);
break;
#endif
default:
break;
}
}
static int nft_ct_set_init(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[])
{
struct nft_ct *priv = nft_expr_priv(expr);
unsigned int len;
int err;
priv->dir = IP_CT_DIR_MAX;
priv->key = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
switch (priv->key) {
#ifdef CONFIG_NF_CONNTRACK_MARK
case NFT_CT_MARK:
if (tb[NFTA_CT_DIRECTION])
return -EINVAL;
len = sizeof_field(struct nf_conn, mark);
break;
#endif
#ifdef CONFIG_NF_CONNTRACK_LABELS
case NFT_CT_LABELS:
if (tb[NFTA_CT_DIRECTION])
return -EINVAL;
len = NF_CT_LABELS_MAX_SIZE;
err = nf_connlabels_get(ctx->net, (len * BITS_PER_BYTE) - 1);
if (err)
return err;
break;
#endif
#ifdef CONFIG_NF_CONNTRACK_ZONES
case NFT_CT_ZONE:
mutex_lock(&nft_ct_pcpu_mutex);
if (!nft_ct_tmpl_alloc_pcpu()) {
mutex_unlock(&nft_ct_pcpu_mutex);
return -ENOMEM;
}
nft_ct_pcpu_template_refcnt++;
mutex_unlock(&nft_ct_pcpu_mutex);
len = sizeof(u16);
break;
#endif
#ifdef CONFIG_NF_CONNTRACK_EVENTS
case NFT_CT_EVENTMASK:
if (tb[NFTA_CT_DIRECTION])
return -EINVAL;
len = sizeof(u32);
break;
#endif
#ifdef CONFIG_NF_CONNTRACK_SECMARK
case NFT_CT_SECMARK:
if (tb[NFTA_CT_DIRECTION])
return -EINVAL;
len = sizeof(u32);
break;
#endif
default:
return -EOPNOTSUPP;
}
if (tb[NFTA_CT_DIRECTION]) {
priv->dir = nla_get_u8(tb[NFTA_CT_DIRECTION]);
switch (priv->dir) {
case IP_CT_DIR_ORIGINAL:
case IP_CT_DIR_REPLY:
break;
default:
err = -EINVAL;
goto err1;
}
}
priv->len = len;
err = nft_parse_register_load(ctx, tb[NFTA_CT_SREG], &priv->sreg, len);
if (err < 0)
goto err1;
err = nf_ct_netns_get(ctx->net, ctx->family);
if (err < 0)
goto err1;
return 0;
err1:
__nft_ct_set_destroy(ctx, priv);
return err;
}
static void nft_ct_get_destroy(const struct nft_ctx *ctx,
const struct nft_expr *expr)
{
nf_ct_netns_put(ctx->net, ctx->family);
}
static void nft_ct_set_destroy(const struct nft_ctx *ctx,
const struct nft_expr *expr)
{
struct nft_ct *priv = nft_expr_priv(expr);
__nft_ct_set_destroy(ctx, priv);
nf_ct_netns_put(ctx->net, ctx->family);
}
static int nft_ct_get_dump(struct sk_buff *skb,
const struct nft_expr *expr, bool reset)
{
const struct nft_ct *priv = nft_expr_priv(expr);
if (nft_dump_register(skb, NFTA_CT_DREG, priv->dreg))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key)))
goto nla_put_failure;
switch (priv->key) {
case NFT_CT_SRC:
case NFT_CT_DST:
case NFT_CT_SRC_IP:
case NFT_CT_DST_IP:
case NFT_CT_SRC_IP6:
case NFT_CT_DST_IP6:
case NFT_CT_PROTO_SRC:
case NFT_CT_PROTO_DST:
if (nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir))
goto nla_put_failure;
break;
case NFT_CT_BYTES:
case NFT_CT_PKTS:
case NFT_CT_AVGPKT:
case NFT_CT_ZONE:
if (priv->dir < IP_CT_DIR_MAX &&
nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir))
goto nla_put_failure;
break;
default:
break;
}
return 0;
nla_put_failure:
return -1;
}
static bool nft_ct_get_reduce(struct nft_regs_track *track,
const struct nft_expr *expr)
{
const struct nft_ct *priv = nft_expr_priv(expr);
const struct nft_ct *ct;
if (!nft_reg_track_cmp(track, expr, priv->dreg)) {
nft_reg_track_update(track, expr, priv->dreg, priv->len);
return false;
}
ct = nft_expr_priv(track->regs[priv->dreg].selector);
if (priv->key != ct->key) {
nft_reg_track_update(track, expr, priv->dreg, priv->len);
return false;
}
if (!track->regs[priv->dreg].bitwise)
return true;
return nft_expr_reduce_bitwise(track, expr);
}
static int nft_ct_set_dump(struct sk_buff *skb,
const struct nft_expr *expr, bool reset)
{
const struct nft_ct *priv = nft_expr_priv(expr);
if (nft_dump_register(skb, NFTA_CT_SREG, priv->sreg))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_CT_KEY, htonl(priv->key)))
goto nla_put_failure;
switch (priv->key) {
case NFT_CT_ZONE:
if (priv->dir < IP_CT_DIR_MAX &&
nla_put_u8(skb, NFTA_CT_DIRECTION, priv->dir))
goto nla_put_failure;
break;
default:
break;
}
return 0;
nla_put_failure:
return -1;
}
static struct nft_expr_type nft_ct_type;
static const struct nft_expr_ops nft_ct_get_ops = {
.type = &nft_ct_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
.eval = nft_ct_get_eval,
.init = nft_ct_get_init,
.destroy = nft_ct_get_destroy,
.dump = nft_ct_get_dump,
.reduce = nft_ct_get_reduce,
};
static bool nft_ct_set_reduce(struct nft_regs_track *track,
const struct nft_expr *expr)
{
int i;
for (i = 0; i < NFT_REG32_NUM; i++) {
if (!track->regs[i].selector)
continue;
if (track->regs[i].selector->ops != &nft_ct_get_ops)
continue;
__nft_reg_track_cancel(track, i);
}
return false;
}
#ifdef CONFIG_MITIGATION_RETPOLINE
static const struct nft_expr_ops nft_ct_get_fast_ops = {
.type = &nft_ct_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
.eval = nft_ct_get_fast_eval,
.init = nft_ct_get_init,
.destroy = nft_ct_get_destroy,
.dump = nft_ct_get_dump,
.reduce = nft_ct_set_reduce,
};
#endif
static const struct nft_expr_ops nft_ct_set_ops = {
.type = &nft_ct_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
.eval = nft_ct_set_eval,
.init = nft_ct_set_init,
.destroy = nft_ct_set_destroy,
.dump = nft_ct_set_dump,
.reduce = nft_ct_set_reduce,
};
#ifdef CONFIG_NF_CONNTRACK_ZONES
static const struct nft_expr_ops nft_ct_set_zone_ops = {
.type = &nft_ct_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_ct)),
.eval = nft_ct_set_zone_eval,
.init = nft_ct_set_init,
.destroy = nft_ct_set_destroy,
.dump = nft_ct_set_dump,
.reduce = nft_ct_set_reduce,
};
#endif
static const struct nft_expr_ops *
nft_ct_select_ops(const struct nft_ctx *ctx,
const struct nlattr * const tb[])
{
if (tb[NFTA_CT_KEY] == NULL)
return ERR_PTR(-EINVAL);
if (tb[NFTA_CT_DREG] && tb[NFTA_CT_SREG])
return ERR_PTR(-EINVAL);
if (tb[NFTA_CT_DREG]) {
#ifdef CONFIG_MITIGATION_RETPOLINE
u32 k = ntohl(nla_get_be32(tb[NFTA_CT_KEY]));
switch (k) {
case NFT_CT_STATE:
case NFT_CT_DIRECTION:
case NFT_CT_STATUS:
case NFT_CT_MARK:
case NFT_CT_SECMARK:
return &nft_ct_get_fast_ops;
}
#endif
return &nft_ct_get_ops;
}
if (tb[NFTA_CT_SREG]) {
#ifdef CONFIG_NF_CONNTRACK_ZONES
if (nla_get_be32(tb[NFTA_CT_KEY]) == htonl(NFT_CT_ZONE))
return &nft_ct_set_zone_ops;
#endif
return &nft_ct_set_ops;
}
return ERR_PTR(-EINVAL);
}
static struct nft_expr_type nft_ct_type __read_mostly = {
.name = "ct",
.select_ops = nft_ct_select_ops,
.policy = nft_ct_policy,
.maxattr = NFTA_CT_MAX,
.owner = THIS_MODULE,
};
static void nft_notrack_eval(const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
struct sk_buff *skb = pkt->skb;
enum ip_conntrack_info ctinfo;
struct nf_conn *ct;
ct = nf_ct_get(pkt->skb, &ctinfo);
/* Previously seen (loopback or untracked)? Ignore. */
if (ct || ctinfo == IP_CT_UNTRACKED)
return;
nf_ct_set(skb, ct, IP_CT_UNTRACKED);
}
static struct nft_expr_type nft_notrack_type;
static const struct nft_expr_ops nft_notrack_ops = {
.type = &nft_notrack_type,
.size = NFT_EXPR_SIZE(0),
.eval = nft_notrack_eval,
.reduce = NFT_REDUCE_READONLY,
};
static struct nft_expr_type nft_notrack_type __read_mostly = {
.name = "notrack",
.ops = &nft_notrack_ops,
.owner = THIS_MODULE,
};
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
static int
nft_ct_timeout_parse_policy(void *timeouts,
const struct nf_conntrack_l4proto *l4proto,
struct net *net, const struct nlattr *attr)
{
struct nlattr **tb;
int ret = 0;
tb = kcalloc(l4proto->ctnl_timeout.nlattr_max + 1, sizeof(*tb),
GFP_KERNEL);
if (!tb)
return -ENOMEM;
ret = nla_parse_nested_deprecated(tb,
l4proto->ctnl_timeout.nlattr_max,
attr,
l4proto->ctnl_timeout.nla_policy,
NULL);
if (ret < 0)
goto err;
ret = l4proto->ctnl_timeout.nlattr_to_obj(tb, net, timeouts);
err:
kfree(tb);
return ret;
}
struct nft_ct_timeout_obj {
struct nf_ct_timeout *timeout;
u8 l4proto;
};
static void nft_ct_timeout_obj_eval(struct nft_object *obj,
struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
const struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
struct nf_conn *ct = (struct nf_conn *)skb_nfct(pkt->skb);
struct nf_conn_timeout *timeout;
const unsigned int *values;
if (priv->l4proto != pkt->tprot)
return;
if (!ct || nf_ct_is_template(ct) || nf_ct_is_confirmed(ct))
return;
timeout = nf_ct_timeout_find(ct);
if (!timeout) {
timeout = nf_ct_timeout_ext_add(ct, priv->timeout, GFP_ATOMIC);
if (!timeout) {
regs->verdict.code = NF_DROP;
return;
}
}
rcu_assign_pointer(timeout->timeout, priv->timeout);
/* adjust the timeout as per 'new' state. ct is unconfirmed,
* so the current timestamp must not be added.
*/
values = nf_ct_timeout_data(timeout);
if (values)
nf_ct_refresh(ct, pkt->skb, values[0]);
}
static int nft_ct_timeout_obj_init(const struct nft_ctx *ctx,
const struct nlattr * const tb[],
struct nft_object *obj)
{
struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
const struct nf_conntrack_l4proto *l4proto;
struct nf_ct_timeout *timeout;
int l3num = ctx->family;
__u8 l4num;
int ret;
if (!tb[NFTA_CT_TIMEOUT_L4PROTO] ||
!tb[NFTA_CT_TIMEOUT_DATA])
return -EINVAL;
if (tb[NFTA_CT_TIMEOUT_L3PROTO])
l3num = ntohs(nla_get_be16(tb[NFTA_CT_TIMEOUT_L3PROTO]));
l4num = nla_get_u8(tb[NFTA_CT_TIMEOUT_L4PROTO]);
priv->l4proto = l4num;
l4proto = nf_ct_l4proto_find(l4num);
if (l4proto->l4proto != l4num) {
ret = -EOPNOTSUPP;
goto err_proto_put;
}
timeout = kzalloc(sizeof(struct nf_ct_timeout) +
l4proto->ctnl_timeout.obj_size, GFP_KERNEL);
if (timeout == NULL) {
ret = -ENOMEM;
goto err_proto_put;
}
ret = nft_ct_timeout_parse_policy(&timeout->data, l4proto, ctx->net,
tb[NFTA_CT_TIMEOUT_DATA]);
if (ret < 0)
goto err_free_timeout;
timeout->l3num = l3num;
timeout->l4proto = l4proto;
ret = nf_ct_netns_get(ctx->net, ctx->family);
if (ret < 0)
goto err_free_timeout;
priv->timeout = timeout;
return 0;
err_free_timeout:
kfree(timeout);
err_proto_put:
return ret;
}
static void nft_ct_timeout_obj_destroy(const struct nft_ctx *ctx,
struct nft_object *obj)
{
struct nft_ct_timeout_obj *priv = nft_obj_data(obj);
struct nf_ct_timeout *timeout = priv->timeout;
nf_ct_untimeout(ctx->net, timeout);
nf_ct_netns_put(ctx->net, ctx->family);
kfree(priv->timeout);
}