This patch adds a new NFT_MSG_GETOBJ_RESET command perform an atomic
dump-and-reset of the stateful object. This also comes with add support
for atomic dump and reset for counter and quota objects.
Signed-off-by: Pablo Neira Ayuso <pa...@netfilter.org>
---
include/net/netfilter/nf_tables.h | 3 +-
include/uapi/linux/netfilter/nf_tables.h | 2 ++
net/netfilter/nf_tables_api.c | 29 ++++++++++++-----
net/netfilter/nft_counter.c | 56 +++++++++++++++++++++++++++-----
net/netfilter/nft_quota.c | 18 ++++++----
5 files changed, 85 insertions(+), 23 deletions(-)
diff --git a/include/net/netfilter/nf_tables.h
b/include/net/netfilter/nf_tables.h
index 903cd618f50e..6f7d6a1dc09c 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -997,7 +997,8 @@ struct nft_object_type {
struct nft_object *obj);
void (*destroy)(struct nft_object *obj);
int (*dump)(struct sk_buff *skb,
- const struct nft_object *obj);
+ struct nft_object *obj,
+ bool reset);
};
int nft_register_obj(struct nft_object_type *obj_type);
diff --git a/include/uapi/linux/netfilter/nf_tables.h
b/include/uapi/linux/netfilter/nf_tables.h
index 3d47582caa80..399eac1eee91 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -89,6 +89,7 @@ enum nft_verdicts {
* @NFT_MSG_NEWOBJ: create a stateful object (enum nft_obj_attributes)
* @NFT_MSG_GETOBJ: get a stateful object (enum nft_obj_attributes)
* @NFT_MSG_DELOBJ: delete a stateful object (enum nft_obj_attributes)
+ * @NFT_MSG_GETOBJ_RESET: get and reset a stateful object (enum
nft_obj_attributes)
*/
enum nf_tables_msg_types {
NFT_MSG_NEWTABLE,
@@ -112,6 +113,7 @@ enum nf_tables_msg_types {
NFT_MSG_NEWOBJ,
NFT_MSG_GETOBJ,
NFT_MSG_DELOBJ,
+ NFT_MSG_GETOBJ_RESET,
NFT_MSG_MAX,
};
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 2ae717c5dcb8..bfc015af366a 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3972,14 +3972,14 @@ static struct nft_object *nft_obj_init(const struct
nft_object_type *type,
}
static int nft_object_dump(struct sk_buff *skb, unsigned int attr,
- const struct nft_object *obj)
+ struct nft_object *obj, bool reset)
{
struct nlattr *nest;
nest = nla_nest_start(skb, attr);
if (!nest)
goto nla_put_failure;
- if (obj->type->dump(skb, obj) < 0)
+ if (obj->type->dump(skb, obj, reset) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest);
return 0;
@@ -4096,7 +4096,7 @@ static int nf_tables_newobj(struct net *net, struct sock
*nlsk,
static int nf_tables_fill_obj_info(struct sk_buff *skb, struct net *net,
u32 portid, u32 seq, int event, u32 flags,
int family, const struct nft_table *table,
- const struct nft_object *obj)
+ struct nft_object *obj, bool reset)
{
struct nfgenmsg *nfmsg;
struct nlmsghdr *nlh;
@@ -4115,7 +4115,7 @@ static int nf_tables_fill_obj_info(struct sk_buff *skb,
struct net *net,
nla_put_string(skb, NFTA_OBJ_NAME, obj->name) ||
nla_put_be32(skb, NFTA_OBJ_TYPE, htonl(obj->type->type)) ||
nla_put_be32(skb, NFTA_OBJ_USE, htonl(obj->use)) ||
- nft_object_dump(skb, NFTA_OBJ_DATA, obj))
+ nft_object_dump(skb, NFTA_OBJ_DATA, obj, reset))
goto nla_put_failure;
nlmsg_end(skb, nlh);
@@ -4131,10 +4131,14 @@ static int nf_tables_dump_obj(struct sk_buff *skb,
struct netlink_callback *cb)
const struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
const struct nft_af_info *afi;
const struct nft_table *table;
- const struct nft_object *obj;
unsigned int idx = 0, s_idx = cb->args[0];
struct net *net = sock_net(skb->sk);
int family = nfmsg->nfgen_family;
+ struct nft_object *obj;
+ bool reset = false;
+
+ if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) == NFT_MSG_GETOBJ_RESET)
+ reset = true;
rcu_read_lock();
cb->seq = net->nft.base_seq;
@@ -4156,7 +4160,7 @@ static int nf_tables_dump_obj(struct sk_buff *skb, struct
netlink_callback *cb)
cb->nlh->nlmsg_seq,
NFT_MSG_NEWOBJ,
NLM_F_MULTI |
NLM_F_APPEND,
- afi->family, table,
obj) < 0)
+ afi->family, table,
obj, reset) < 0)
goto done;
nl_dump_check_consistent(cb, nlmsg_hdr(skb));
@@ -4183,6 +4187,7 @@ static int nf_tables_getobj(struct net *net, struct sock
*nlsk,
const struct nft_table *table;
struct nft_object *obj;
struct sk_buff *skb2;
+ bool reset = false;
u32 objtype;
int err;
@@ -4214,9 +4219,12 @@ static int nf_tables_getobj(struct net *net, struct sock
*nlsk,
if (!skb2)
return -ENOMEM;
+ if (NFNL_MSG_TYPE(nlh->nlmsg_type) == NFT_MSG_GETOBJ_RESET)
+ reset = true;
+
err = nf_tables_fill_obj_info(skb2, net, NETLINK_CB(skb).portid,
nlh->nlmsg_seq, NFT_MSG_NEWOBJ, 0,
- family, table, obj);
+ family, table, obj, reset);
if (err < 0)
goto err;
@@ -4291,7 +4299,7 @@ static int nf_tables_obj_notify(const struct nft_ctx *ctx,
err = nf_tables_fill_obj_info(skb, ctx->net, ctx->portid, ctx->seq,
event, 0, ctx->afi->family, ctx->table,
- obj);
+ obj, false);
if (err < 0) {
kfree_skb(skb);
goto err;
@@ -4482,6 +4490,11 @@ static const struct nfnl_callback
nf_tables_cb[NFT_MSG_MAX] = {
.attr_count = NFTA_OBJ_MAX,
.policy = nft_obj_policy,
},
+ [NFT_MSG_GETOBJ_RESET] = {
+ .call = nf_tables_getobj,
+ .attr_count = NFTA_OBJ_MAX,
+ .policy = nft_obj_policy,
+ },
};
static void nft_chain_commit_update(struct nft_trans *trans)
diff --git a/net/netfilter/nft_counter.c b/net/netfilter/nft_counter.c
index 6f3dd429f865..f6a02c5071c2 100644
--- a/net/netfilter/nft_counter.c
+++ b/net/netfilter/nft_counter.c
@@ -100,10 +100,10 @@ static void nft_counter_obj_destroy(struct nft_object
*obj)
nft_counter_do_destroy(priv);
}
-static void nft_counter_fetch(const struct nft_counter_percpu __percpu
*counter,
+static void nft_counter_fetch(struct nft_counter_percpu __percpu *counter,
struct nft_counter *total)
{
- const struct nft_counter_percpu *cpu_stats;
+ struct nft_counter_percpu *cpu_stats;
u64 bytes, packets;
unsigned int seq;
int cpu;
@@ -122,12 +122,52 @@ static void nft_counter_fetch(const struct
nft_counter_percpu __percpu *counter,
}
}
+static u64 __nft_counter_reset(u64 *counter)
+{
+ u64 ret, old;
+
+ do {
+ old = *counter;
+ ret = cmpxchg64(counter, old, 0);
+ } while (ret != old);
+
+ return ret;
+}
+
+static void nft_counter_reset(struct nft_counter_percpu __percpu *counter,
+ struct nft_counter *total)
+{
+ struct nft_counter_percpu *cpu_stats;
+ u64 bytes, packets;
+ unsigned int seq;
+ int cpu;
+
+ memset(total, 0, sizeof(*total));
+ for_each_possible_cpu(cpu) {
+ bytes = packets = 0;
+
+ cpu_stats = per_cpu_ptr(counter, cpu);
+ do {
+ seq = u64_stats_fetch_begin_irq(&cpu_stats->syncp);
+ packets +=
__nft_counter_reset(&cpu_stats->counter.packets);
+ bytes +=
__nft_counter_reset(&cpu_stats->counter.bytes);
+ } while (u64_stats_fetch_retry_irq(&cpu_stats->syncp, seq));
+
+ total->packets += packets;
+ total->bytes += bytes;
+ }
+}
+
static int nft_counter_do_dump(struct sk_buff *skb,
- const struct nft_counter_percpu_priv *priv)
+ const struct nft_counter_percpu_priv *priv,
+ bool reset)
{
struct nft_counter total;
- nft_counter_fetch(priv->counter, &total);
+ if (reset)
+ nft_counter_reset(priv->counter, &total);
+ else
+ nft_counter_fetch(priv->counter, &total);
if (nla_put_be64(skb, NFTA_COUNTER_BYTES, cpu_to_be64(total.bytes),
NFTA_COUNTER_PAD) ||
@@ -141,11 +181,11 @@ static int nft_counter_do_dump(struct sk_buff *skb,
}
static int nft_counter_obj_dump(struct sk_buff *skb,
- const struct nft_object *obj)
+ struct nft_object *obj, bool reset)
{
- const struct nft_counter_percpu_priv *priv = nft_obj_data(obj);
+ struct nft_counter_percpu_priv *priv = nft_obj_data(obj);
- return nft_counter_do_dump(skb, priv);
+ return nft_counter_do_dump(skb, priv, reset);
}
static const struct nla_policy nft_counter_policy[NFTA_COUNTER_MAX + 1] = {
@@ -178,7 +218,7 @@ static int nft_counter_dump(struct sk_buff *skb, const
struct nft_expr *expr)
{
const struct nft_counter_percpu_priv *priv = nft_expr_priv(expr);
- return nft_counter_do_dump(skb, priv);
+ return nft_counter_do_dump(skb, priv, false);
}
static int nft_counter_init(const struct nft_ctx *ctx,
diff --git a/net/netfilter/nft_quota.c b/net/netfilter/nft_quota.c
index 0d344209803a..5d25f57497cb 100644
--- a/net/netfilter/nft_quota.c
+++ b/net/netfilter/nft_quota.c
@@ -83,12 +83,17 @@ static int nft_quota_obj_init(const struct nlattr * const
tb[],
return nft_quota_do_init(tb, priv);
}
-static int nft_quota_do_dump(struct sk_buff *skb, const struct nft_quota *priv)
+static int nft_quota_do_dump(struct sk_buff *skb, struct nft_quota *priv,
+ bool reset)
{
u32 flags = priv->invert ? NFT_QUOTA_F_INV : 0;
u64 consumed;
- consumed = atomic64_read(&priv->consumed);
+ if (reset)
+ consumed = atomic64_xchg(&priv->consumed, 0);
+ else
+ consumed = atomic64_read(&priv->consumed);
+
/* Since we inconditionally increment consumed quota for each packet
* that we see, don't go over the quota boundary in what we send to
* userspace.
@@ -108,11 +113,12 @@ static int nft_quota_do_dump(struct sk_buff *skb, const
struct nft_quota *priv)
return -1;
}
-static int nft_quota_obj_dump(struct sk_buff *skb, const struct nft_object
*obj)
+static int nft_quota_obj_dump(struct sk_buff *skb, struct nft_object *obj,
+ bool reset)
{
struct nft_quota *priv = nft_obj_data(obj);
- return nft_quota_do_dump(skb, priv);
+ return nft_quota_do_dump(skb, priv, reset);
}
static struct nft_object_type nft_quota_obj __read_mostly = {
@@ -146,9 +152,9 @@ static int nft_quota_init(const struct nft_ctx *ctx,
static int nft_quota_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
- const struct nft_quota *priv = nft_expr_priv(expr);
+ struct nft_quota *priv = nft_expr_priv(expr);
- return nft_quota_do_dump(skb, priv);
+ return nft_quota_do_dump(skb, priv, false);
}
static struct nft_expr_type nft_quota_type;
--
2.1.4
