This patch adds three new netlink attribute to encapsulate a list of
expressions per set elements:
- NFTA_SET_EXPRESSIONS: this attribute provides the set definition in
terms of expressions. New set elements get attached the list of
expressions that is specified by this new netlink attribute.
- NFTA_SET_ELEM_EXPRESSIONS: this attribute allows users to restore (or
initialize) the stateful information of set elements when adding an
element to the set.
- NFTA_DYNSET_EXPRESSIONS: this attribute specifies the list of
expressions that the set element gets when it is inserted from the
packet path.
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
v4: rework patch without nft_expr_parse() helper function.
include/uapi/linux/netfilter/nf_tables.h | 6 ++
net/netfilter/nf_tables_api.c | 80 +++++++++++++++++++++++-
net/netfilter/nft_dynset.c | 49 ++++++++++++++-
3 files changed, 129 insertions(+), 6 deletions(-)
diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 98272cb5f617..28b6ee53305f 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -361,6 +361,7 @@ enum nft_set_field_attributes {
* @NFTA_SET_OBJ_TYPE: stateful object type (NLA_U32: NFT_OBJECT_*)
* @NFTA_SET_HANDLE: set handle (NLA_U64)
* @NFTA_SET_EXPR: set expression (NLA_NESTED: nft_expr_attributes)
+ * @NFTA_SET_EXPRESSIONS: list of expressions (NLA_NESTED: nft_list_attributes)
*/
enum nft_set_attributes {
NFTA_SET_UNSPEC,
@@ -381,6 +382,7 @@ enum nft_set_attributes {
NFTA_SET_OBJ_TYPE,
NFTA_SET_HANDLE,
NFTA_SET_EXPR,
+ NFTA_SET_EXPRESSIONS,
__NFTA_SET_MAX
};
#define NFTA_SET_MAX (__NFTA_SET_MAX - 1)
@@ -406,6 +408,7 @@ enum nft_set_elem_flags {
* @NFTA_SET_ELEM_EXPR: expression (NLA_NESTED: nft_expr_attributes)
* @NFTA_SET_ELEM_OBJREF: stateful object reference (NLA_STRING)
* @NFTA_SET_ELEM_KEY_END: closing key value (NLA_NESTED: nft_data)
+ * @NFTA_SET_ELEM_EXPRESSIONS: list of expressions (NLA_NESTED: nft_list_attributes)
*/
enum nft_set_elem_attributes {
NFTA_SET_ELEM_UNSPEC,
@@ -419,6 +422,7 @@ enum nft_set_elem_attributes {
NFTA_SET_ELEM_PAD,
NFTA_SET_ELEM_OBJREF,
NFTA_SET_ELEM_KEY_END,
+ NFTA_SET_ELEM_EXPRESSIONS,
__NFTA_SET_ELEM_MAX
};
#define NFTA_SET_ELEM_MAX (__NFTA_SET_ELEM_MAX - 1)
@@ -715,6 +719,7 @@ enum nft_dynset_flags {
* @NFTA_DYNSET_TIMEOUT: timeout value for the new element (NLA_U64)
* @NFTA_DYNSET_EXPR: expression (NLA_NESTED: nft_expr_attributes)
* @NFTA_DYNSET_FLAGS: flags (NLA_U32)
+ * @NFTA_DYNSET_EXPRESSIONS: list of expressions (NLA_NESTED: nft_list_attributes)
*/
enum nft_dynset_attributes {
NFTA_DYNSET_UNSPEC,
@@ -727,6 +732,7 @@ enum nft_dynset_attributes {
NFTA_DYNSET_EXPR,
NFTA_DYNSET_PAD,
NFTA_DYNSET_FLAGS,
+ NFTA_DYNSET_EXPRESSIONS,
__NFTA_DYNSET_MAX,
};
#define NFTA_DYNSET_MAX (__NFTA_DYNSET_MAX - 1)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 41b83278efef..90ca15809f97 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -3566,6 +3566,7 @@ static const struct nla_policy nft_set_policy[NFTA_SET_MAX + 1] = {
[NFTA_SET_OBJ_TYPE] = { .type = NLA_U32 },
[NFTA_SET_HANDLE] = { .type = NLA_U64 },
[NFTA_SET_EXPR] = { .type = NLA_NESTED },
+ [NFTA_SET_EXPRESSIONS] = { .type = NLA_NESTED },
};
static const struct nla_policy nft_set_desc_policy[NFTA_SET_DESC_MAX + 1] = {
@@ -3773,6 +3774,7 @@ static int nf_tables_fill_set(struct sk_buff *skb, const struct nft_ctx *ctx,
u32 portid = ctx->portid;
struct nlattr *nest;
u32 seq = ctx->seq;
+ int i;
event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct nfgenmsg),
@@ -3847,6 +3849,17 @@ static int nf_tables_fill_set(struct sk_buff *skb, const struct nft_ctx *ctx,
goto nla_put_failure;
nla_nest_end(skb, nest);
+ } else if (set->num_exprs > 1) {
+ nest = nla_nest_start_noflag(skb, NFTA_SET_EXPRESSIONS);
+ if (nest == NULL)
+ goto nla_put_failure;
+
+ for (i = 0; i < set->num_exprs; i++) {
+ if (nft_expr_dump(skb, NFTA_LIST_ELEM,
+ set->exprs[i]) < 0)
+ goto nla_put_failure;
+ }
+ nla_nest_end(skb, nest);
}
nlmsg_end(skb, nlh);
@@ -4215,7 +4228,7 @@ static int nf_tables_newset(struct net *net, struct sock *nlsk,
return err;
}
- if (nla[NFTA_SET_EXPR])
+ if (nla[NFTA_SET_EXPR] || nla[NFTA_SET_EXPRESSIONS])
desc.expr = true;
table = nft_table_lookup(net, nla[NFTA_SET_TABLE], family, genmask);
@@ -4281,6 +4294,25 @@ static int nf_tables_newset(struct net *net, struct sock *nlsk,
}
set->exprs[0] = expr;
set->num_exprs++;
+ } else if (nla[NFTA_SET_EXPRESSIONS]) {
+ struct nft_expr *expr;
+ struct nlattr *tmp;
+ int left;
+
+ i = 0;
+ nla_for_each_nested(tmp, nla[NFTA_SET_EXPRESSIONS], left) {
+ if (i == NFT_SET_EXPR_MAX) {
+ err = -E2BIG;
+ goto err_set_init;
+ }
+ expr = nft_set_elem_expr_alloc(&ctx, set, tmp);
+ if (IS_ERR(expr)) {
+ err = PTR_ERR(expr);
+ goto err_set_init;
+ }
+ set->exprs[i++] = expr;
+ set->num_exprs++;
+ }
}
udata = NULL;
@@ -4540,6 +4572,7 @@ static const struct nla_policy nft_set_elem_policy[NFTA_SET_ELEM_MAX + 1] = {
[NFTA_SET_ELEM_OBJREF] = { .type = NLA_STRING,
.len = NFT_OBJ_MAXNAMELEN - 1 },
[NFTA_SET_ELEM_KEY_END] = { .type = NLA_NESTED },
+ [NFTA_SET_ELEM_EXPRESSIONS] = { .type = NLA_NESTED },
};
static const struct nla_policy nft_set_elem_list_policy[NFTA_SET_ELEM_LIST_MAX + 1] = {
@@ -4580,6 +4613,7 @@ static int nft_set_elem_expr_dump(struct sk_buff *skb,
struct nft_set_elem_expr *elem_expr;
u32 size, num_exprs = 0;
struct nft_expr *expr;
+ struct nlattr *nest;
elem_expr = nft_set_ext_expr(ext);
nft_setelem_expr_foreach(expr, elem_expr, size)
@@ -4591,9 +4625,22 @@ static int nft_set_elem_expr_dump(struct sk_buff *skb,
return -1;
return 0;
- }
+ } else if (num_exprs > 1) {
+ nest = nla_nest_start_noflag(skb, NFTA_SET_ELEM_EXPRESSIONS);
+ if (nest == NULL)
+ goto nla_put_failure;
+ nft_setelem_expr_foreach(expr, elem_expr, size) {
+ expr = nft_setelem_expr_at(elem_expr, size);
+ if (nft_expr_dump(skb, NFTA_LIST_ELEM, expr) < 0)
+ goto nla_put_failure;
+ }
+ nla_nest_end(skb, nest);
+ }
return 0;
+
+nla_put_failure:
+ return -1;
}
static int nf_tables_fill_setelem(struct sk_buff *skb,
@@ -5268,7 +5315,8 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
nla[NFTA_SET_ELEM_TIMEOUT] ||
nla[NFTA_SET_ELEM_EXPIRATION] ||
nla[NFTA_SET_ELEM_USERDATA] ||
- nla[NFTA_SET_ELEM_EXPR]))
+ nla[NFTA_SET_ELEM_EXPR] ||
+ nla[NFTA_SET_ELEM_EXPRESSIONS]))
return -EINVAL;
timeout = 0;
@@ -5307,6 +5355,32 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
err = -EOPNOTSUPP;
goto err_set_elem_expr;
}
+ } else if (nla[NFTA_SET_ELEM_EXPRESSIONS] && set->num_exprs > 0) {
+ struct nft_expr *expr;
+ struct nlattr *tmp;
+ int left;
+
+ i = 0;
+ nla_for_each_nested(tmp, nla[NFTA_SET_ELEM_EXPRESSIONS], left) {
+ if (i == set->num_exprs) {
+ err = -E2BIG;
+ goto err_set_elem_expr;
+ }
+ expr = nft_set_elem_expr_alloc(ctx, set, tmp);
+ if (IS_ERR(expr)) {
+ err = PTR_ERR(expr);
+ goto err_set_elem_expr;
+ }
+ if (expr->ops != set->exprs[i]->ops) {
+ err = -EOPNOTSUPP;
+ goto err_set_elem_expr;
+ }
+ expr_array[i++] = expr;
+ }
+ if (set->num_exprs != i) {
+ err = -EOPNOTSUPP;
+ goto err_set_elem_expr;
+ }
} else if (set->num_exprs > 0) {
err = nft_set_elem_expr_clone(ctx, set, expr_array);
if (err < 0)
diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c
index 939f840f2c56..66613b8dc90a 100644
--- a/net/netfilter/nft_dynset.c
+++ b/net/netfilter/nft_dynset.c
@@ -153,6 +153,7 @@ static const struct nla_policy nft_dynset_policy[NFTA_DYNSET_MAX + 1] = {
[NFTA_DYNSET_TIMEOUT] = { .type = NLA_U64 },
[NFTA_DYNSET_EXPR] = { .type = NLA_NESTED },
[NFTA_DYNSET_FLAGS] = { .type = NLA_U32 },
+ [NFTA_DYNSET_EXPRESSIONS] = { .type = NLA_NESTED },
};
static int nft_dynset_init(const struct nft_ctx *ctx,
@@ -232,12 +233,13 @@ static int nft_dynset_init(const struct nft_ctx *ctx,
} else if (set->flags & NFT_SET_MAP)
return -EINVAL;
+ if ((tb[NFTA_DYNSET_EXPR] || tb[NFTA_DYNSET_EXPRESSIONS]) &&
+ !(set->flags & NFT_SET_EVAL))
+ return -EINVAL;
+
if (tb[NFTA_DYNSET_EXPR]) {
struct nft_expr *dynset_expr;
- if (!(set->flags & NFT_SET_EVAL))
- return -EINVAL;
-
dynset_expr = nft_dynset_expr_alloc(ctx, set,
tb[NFTA_DYNSET_EXPR], 0);
if (IS_ERR(dynset_expr))
@@ -252,6 +254,34 @@ static int nft_dynset_init(const struct nft_ctx *ctx,
priv->num_exprs++;
priv->expr_array[0] = dynset_expr;
+ } else if (tb[NFTA_DYNSET_EXPRESSIONS]) {
+ struct nft_expr *dynset_expr;
+ struct nlattr *tmp;
+ int left;
+
+ i = 0;
+ nla_for_each_nested(tmp, tb[NFTA_DYNSET_EXPRESSIONS], left) {
+ if (i == NFT_SET_EXPR_MAX) {
+ err = -E2BIG;
+ goto err_expr_free;
+ }
+ dynset_expr = nft_dynset_expr_alloc(ctx, set, tmp, i);
+ if (IS_ERR(dynset_expr)) {
+ err = PTR_ERR(dynset_expr);
+ goto err_expr_free;
+ }
+ if (set->num_exprs &&
+ dynset_expr->ops != set->exprs[i]->ops) {
+ err = -EOPNOTSUPP;
+ goto err_expr_free;
+ }
+ priv->expr_array[i++] = dynset_expr;
+ priv->num_exprs++;
+ }
+ if (set->num_exprs && set->num_exprs != i) {
+ err = -EOPNOTSUPP;
+ goto err_expr_free;
+ }
}
nft_set_ext_prepare(&priv->tmpl);
@@ -336,6 +366,19 @@ static int nft_dynset_dump(struct sk_buff *skb, const struct nft_expr *expr)
if (priv->num_exprs == 1) {
if (nft_expr_dump(skb, NFTA_DYNSET_EXPR, priv->expr_array[i]))
goto nla_put_failure;
+ } else if (priv->num_exprs > 1) {
+ struct nlattr *nest;
+
+ nest = nla_nest_start_noflag(skb, NFTA_DYNSET_EXPRESSIONS);
+ if (!nest)
+ goto nla_put_failure;
+
+ for (i = 0; i < priv->num_exprs; i++) {
+ if (nft_expr_dump(skb, NFTA_LIST_ELEM,
+ priv->expr_array[i]))
+ goto nla_put_failure;
+ }
+ nla_nest_end(skb, nest);
}
if (nla_put_be32(skb, NFTA_DYNSET_FLAGS, htonl(flags)))
goto nla_put_failure;
--
2.20.1
