netfilter: nf_tables: Add new attributes into nft_set to store user data.
User data is stored at after 'nft_set_ops' private data into 'data[]'
flexible array. The field 'udata' points to user data and 'udlen' stores
its length.
Add new flag NFTA_SET_USERDATA.
Signed-off-by: Carlos Falgueras García <carlosfg@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 0191fbb..f6b1daf 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -291,6 +291,8 @@
* @timeout: default timeout value in msecs
* @gc_int: garbage collection interval in msecs
* @policy: set parameterization (see enum nft_set_policies)
+ * @udlen: user data length
+ * @udata: user data
* @ops: set ops
* @pnet: network namespace
* @flags: set flags
@@ -310,6 +312,8 @@
u64 timeout;
u32 gc_int;
u16 policy;
+ u16 udlen;
+ unsigned char *udata;
/* runtime data below here */
const struct nft_set_ops *ops ____cacheline_aligned;
possible_net_t pnet;
diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 731288a..03c28a4 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -291,6 +291,7 @@
* @NFTA_SET_ID: uniquely identifies a set in a transaction (NLA_U32)
* @NFTA_SET_TIMEOUT: default timeout value (NLA_U64)
* @NFTA_SET_GC_INTERVAL: garbage collection interval (NLA_U32)
+ * @NFTA_SET_USERDATA: user data (NLA_BINARY)
*/
enum nft_set_attributes {
NFTA_SET_UNSPEC,
@@ -306,6 +307,7 @@
NFTA_SET_ID,
NFTA_SET_TIMEOUT,
NFTA_SET_GC_INTERVAL,
+ NFTA_SET_USERDATA,
__NFTA_SET_MAX
};
#define NFTA_SET_MAX (__NFTA_SET_MAX - 1)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index f5c3971..2011977 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2323,6 +2323,8 @@
[NFTA_SET_ID] = { .type = NLA_U32 },
[NFTA_SET_TIMEOUT] = { .type = NLA_U64 },
[NFTA_SET_GC_INTERVAL] = { .type = NLA_U32 },
+ [NFTA_SET_USERDATA] = { .type = NLA_BINARY,
+ .len = NFT_USERDATA_MAXLEN },
};
static const struct nla_policy nft_set_desc_policy[NFTA_SET_DESC_MAX + 1] = {
@@ -2482,6 +2484,9 @@
goto nla_put_failure;
}
+ if (nla_put(skb, NFTA_SET_USERDATA, set->udlen, set->udata))
+ goto nla_put_failure;
+
desc = nla_nest_start(skb, NFTA_SET_DESC);
if (desc == NULL)
goto nla_put_failure;
@@ -2691,6 +2696,8 @@
u64 timeout;
u32 ktype, dtype, flags, policy, gc_int;
struct nft_set_desc desc;
+ unsigned char *udata;
+ u16 udlen;
int err;
if (nla[NFTA_SET_TABLE] == NULL ||
@@ -2803,12 +2810,16 @@
if (IS_ERR(ops))
return PTR_ERR(ops);
+ udlen = 0;
+ if (nla[NFTA_SET_USERDATA])
+ udlen = nla_len(nla[NFTA_SET_USERDATA]);
+
size = 0;
if (ops->privsize != NULL)
size = ops->privsize(nla);
err = -ENOMEM;
- set = kzalloc(sizeof(*set) + size, GFP_KERNEL);
+ set = kzalloc(sizeof(*set) + size + udlen, GFP_KERNEL);
if (set == NULL)
goto err1;
@@ -2817,6 +2828,12 @@
if (err < 0)
goto err2;
+ udata = NULL;
+ if (udlen) {
+ udata = set->data + size;
+ nla_memcpy(udata, nla[NFTA_SET_USERDATA], udlen);
+ }
+
INIT_LIST_HEAD(&set->bindings);
write_pnet(&set->pnet, net);
set->ops = ops;
@@ -2827,6 +2844,8 @@
set->flags = flags;
set->size = desc.size;
set->policy = policy;
+ set->udlen = udlen;
+ set->udata = udata;
set->timeout = timeout;
set->gc_int = gc_int;