From 8cfd9b0f8515e7c361bba27e2a2684cbd427fe01 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 7 Dec 2020 17:37:01 +0100 Subject: netfilter: nftables: generalize set expressions support Currently, the set infrastucture allows for one single expressions per element. This patch extends the existing infrastructure to allow for up to two expressions. This is not updating the netlink API yet, this is coming as an initial preparation patch. Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_dynset.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/netfilter/nft_dynset.c') diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c index 64ca13a1885b..4353e47c30fc 100644 --- a/net/netfilter/nft_dynset.c +++ b/net/netfilter/nft_dynset.c @@ -188,7 +188,8 @@ static int nft_dynset_init(const struct nft_ctx *ctx, if (IS_ERR(priv->expr)) return PTR_ERR(priv->expr); - if (set->expr && set->expr->ops != priv->expr->ops) { + if (set->num_exprs == 1 && + set->exprs[0]->ops != priv->expr->ops) { err = -EOPNOTSUPP; goto err_expr_free; } -- cgit v1.2.3 From 563125a73ac30d7036ae69ca35c40500562c1de4 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Wed, 9 Dec 2020 20:10:27 +0100 Subject: netfilter: nftables: generalize set extension to support for several expressions This patch replaces NFT_SET_EXPR by NFT_SET_EXT_EXPRESSIONS. This new extension allows to attach several expressions to one set element (not only one single expression as NFT_SET_EXPR provides). This patch prepares for support for several expressions per set element in the netlink userspace API. Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_dynset.c | 103 ++++++++++++++++++++++++++++++++++++--------- 1 file changed, 83 insertions(+), 20 deletions(-) (limited to 'net/netfilter/nft_dynset.c') diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c index 4353e47c30fc..d9e609b2e5d4 100644 --- a/net/netfilter/nft_dynset.c +++ b/net/netfilter/nft_dynset.c @@ -19,11 +19,30 @@ struct nft_dynset { enum nft_registers sreg_key:8; enum nft_registers sreg_data:8; bool invert; + u8 num_exprs; u64 timeout; - struct nft_expr *expr; + struct nft_expr *expr_array[NFT_SET_EXPR_MAX]; struct nft_set_binding binding; }; +static int nft_dynset_expr_setup(const struct nft_dynset *priv, + const struct nft_set_ext *ext) +{ + struct nft_set_elem_expr *elem_expr = nft_set_ext_expr(ext); + struct nft_expr *expr; + int i; + + for (i = 0; i < priv->num_exprs; i++) { + expr = nft_setelem_expr_at(elem_expr, elem_expr->size); + if (nft_expr_clone(expr, priv->expr_array[i]) < 0) + return -1; + + elem_expr->size += priv->expr_array[i]->ops->size; + } + + return 0; +} + static void *nft_dynset_new(struct nft_set *set, const struct nft_expr *expr, struct nft_regs *regs) { @@ -44,8 +63,7 @@ static void *nft_dynset_new(struct nft_set *set, const struct nft_expr *expr, goto err1; ext = nft_set_elem_ext(set, elem); - if (priv->expr != NULL && - nft_expr_clone(nft_set_ext_expr(ext), priv->expr) < 0) + if (priv->num_exprs && nft_dynset_expr_setup(priv, ext) < 0) goto err2; return elem; @@ -90,6 +108,41 @@ void nft_dynset_eval(const struct nft_expr *expr, regs->verdict.code = NFT_BREAK; } +static void nft_dynset_ext_add_expr(struct nft_dynset *priv) +{ + u8 size = 0; + int i; + + for (i = 0; i < priv->num_exprs; i++) + size += priv->expr_array[i]->ops->size; + + nft_set_ext_add_length(&priv->tmpl, NFT_SET_EXT_EXPRESSIONS, + sizeof(struct nft_set_elem_expr) + size); +} + +static struct nft_expr * +nft_dynset_expr_alloc(const struct nft_ctx *ctx, const struct nft_set *set, + const struct nlattr *attr, int pos) +{ + struct nft_expr *expr; + int err; + + expr = nft_set_elem_expr_alloc(ctx, set, attr); + if (IS_ERR(expr)) + return expr; + + if (set->exprs[pos] && set->exprs[pos]->ops != expr->ops) { + err = -EOPNOTSUPP; + goto err_dynset_expr; + } + + return expr; + +err_dynset_expr: + nft_expr_destroy(ctx, expr); + return ERR_PTR(err); +} + static const struct nla_policy nft_dynset_policy[NFTA_DYNSET_MAX + 1] = { [NFTA_DYNSET_SET_NAME] = { .type = NLA_STRING, .len = NFT_SET_MAXNAMELEN - 1 }, @@ -110,7 +163,7 @@ static int nft_dynset_init(const struct nft_ctx *ctx, u8 genmask = nft_genmask_next(ctx->net); struct nft_set *set; u64 timeout; - int err; + int err, i; lockdep_assert_held(&ctx->net->nft.commit_mutex); @@ -179,17 +232,23 @@ static int nft_dynset_init(const struct nft_ctx *ctx, } else if (set->flags & NFT_SET_MAP) return -EINVAL; - if (tb[NFTA_DYNSET_EXPR] != NULL) { + if (tb[NFTA_DYNSET_EXPR]) { + struct nft_expr *dynset_expr; + if (!(set->flags & NFT_SET_EVAL)) return -EINVAL; - priv->expr = nft_set_elem_expr_alloc(ctx, set, - tb[NFTA_DYNSET_EXPR]); - if (IS_ERR(priv->expr)) - return PTR_ERR(priv->expr); + dynset_expr = nft_dynset_expr_alloc(ctx, set, + tb[NFTA_DYNSET_EXPR], 0); + if (IS_ERR(dynset_expr)) + return PTR_ERR(dynset_expr); - if (set->num_exprs == 1 && - set->exprs[0]->ops != priv->expr->ops) { + priv->num_exprs++; + priv->expr_array[0] = dynset_expr; + + if (set->num_exprs > 1 || + (set->num_exprs == 1 && + dynset_expr->ops != set->exprs[0]->ops)) { err = -EOPNOTSUPP; goto err_expr_free; } @@ -199,9 +258,10 @@ static int nft_dynset_init(const struct nft_ctx *ctx, nft_set_ext_add_length(&priv->tmpl, NFT_SET_EXT_KEY, set->klen); if (set->flags & NFT_SET_MAP) nft_set_ext_add_length(&priv->tmpl, NFT_SET_EXT_DATA, set->dlen); - if (priv->expr != NULL) - nft_set_ext_add_length(&priv->tmpl, NFT_SET_EXT_EXPR, - priv->expr->ops->size); + + if (priv->num_exprs) + nft_dynset_ext_add_expr(priv); + if (set->flags & NFT_SET_TIMEOUT) { if (timeout || set->timeout) nft_set_ext_add(&priv->tmpl, NFT_SET_EXT_EXPIRATION); @@ -220,8 +280,8 @@ static int nft_dynset_init(const struct nft_ctx *ctx, return 0; err_expr_free: - if (priv->expr != NULL) - nft_expr_destroy(ctx, priv->expr); + for (i = 0; i < priv->num_exprs; i++) + nft_expr_destroy(ctx, priv->expr_array[i]); return err; } @@ -246,9 +306,10 @@ static void nft_dynset_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) { struct nft_dynset *priv = nft_expr_priv(expr); + int i; - if (priv->expr != NULL) - nft_expr_destroy(ctx, priv->expr); + for (i = 0; i < priv->num_exprs; i++) + nft_expr_destroy(ctx, priv->expr_array[i]); nf_tables_destroy_set(ctx, priv->set); } @@ -271,8 +332,10 @@ static int nft_dynset_dump(struct sk_buff *skb, const struct nft_expr *expr) cpu_to_be64(jiffies_to_msecs(priv->timeout)), NFTA_DYNSET_PAD)) goto nla_put_failure; - if (priv->expr && nft_expr_dump(skb, NFTA_DYNSET_EXPR, priv->expr)) - goto nla_put_failure; + if (priv->num_exprs == 1) { + if (nft_expr_dump(skb, NFTA_DYNSET_EXPR, priv->expr_array[0])) + goto nla_put_failure; + } if (nla_put_be32(skb, NFTA_DYNSET_FLAGS, htonl(flags))) goto nla_put_failure; return 0; -- cgit v1.2.3 From 48b0ae046ee96eac999839f6d26c624b8c93ed66 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 7 Dec 2020 17:37:14 +0100 Subject: netfilter: nftables: netlink support for several set element expressions This patch adds three new netlink attributes 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 --- net/netfilter/nft_dynset.c | 56 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 53 insertions(+), 3 deletions(-) (limited to 'net/netfilter/nft_dynset.c') diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c index d9e609b2e5d4..13c426d5dcf9 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 +254,40 @@ static int nft_dynset_init(const struct nft_ctx *ctx, err = -EOPNOTSUPP; goto err_expr_free; } + } 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; + } + if (nla_type(tmp) != NFTA_LIST_ELEM) { + err = -EINVAL; + 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; + } + priv->expr_array[i] = dynset_expr; + priv->num_exprs++; + + if (set->num_exprs && + dynset_expr->ops != set->exprs[i]->ops) { + err = -EOPNOTSUPP; + goto err_expr_free; + } + i++; + } + if (set->num_exprs && set->num_exprs != i) { + err = -EOPNOTSUPP; + goto err_expr_free; + } } nft_set_ext_prepare(&priv->tmpl); @@ -318,6 +354,7 @@ static int nft_dynset_dump(struct sk_buff *skb, const struct nft_expr *expr) { const struct nft_dynset *priv = nft_expr_priv(expr); u32 flags = priv->invert ? NFT_DYNSET_F_INV : 0; + int i; if (nft_dump_register(skb, NFTA_DYNSET_SREG_KEY, priv->sreg_key)) goto nla_put_failure; @@ -335,6 +372,19 @@ 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[0])) 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; -- cgit v1.2.3