From d77a721d212d48e2ff62334e00cc4cfcad751ff5 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 14 Mar 2022 18:23:09 +0100 Subject: [PATCH] netfilter: nft_socket: track register operations Check if the destination register already contains the data that this socket expression performs. This allows to skip this redundant operation. If the destination contains a different selector, update the register tracking information. Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_socket.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/net/netfilter/nft_socket.c b/net/netfilter/nft_socket.c index d601974..bd3792f 100644 --- a/net/netfilter/nft_socket.c +++ b/net/netfilter/nft_socket.c @@ -10,6 +10,7 @@ struct nft_socket { enum nft_socket_keys key:8; u8 level; + u8 len; union { u8 dreg; }; @@ -179,6 +180,7 @@ static int nft_socket_init(const struct nft_ctx *ctx, return -EOPNOTSUPP; } + priv->len = len; return nft_parse_register_store(ctx, tb[NFTA_SOCKET_DREG], &priv->dreg, NULL, NFT_DATA_VALUE, len); } @@ -198,6 +200,31 @@ static int nft_socket_dump(struct sk_buff *skb, return 0; } +static bool nft_socket_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + const struct nft_socket *priv = nft_expr_priv(expr); + const struct nft_socket *socket; + + if (!nft_reg_track_cmp(track, expr, priv->dreg)) { + nft_reg_track_update(track, expr, priv->dreg, priv->len); + return false; + } + + socket = nft_expr_priv(track->regs[priv->dreg].selector); + if (priv->key != socket->key || + priv->dreg != socket->dreg || + priv->level != socket->level) { + 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 struct nft_expr_type nft_socket_type; static const struct nft_expr_ops nft_socket_ops = { .type = &nft_socket_type, @@ -205,6 +232,7 @@ static const struct nft_expr_ops nft_socket_ops = { .eval = nft_socket_eval, .init = nft_socket_init, .dump = nft_socket_dump, + .reduce = nft_socket_reduce, }; static struct nft_expr_type nft_socket_type __read_mostly = { -- 2.7.4