diff options
Diffstat (limited to 'net/netfilter/nft_socket.c')
| -rw-r--r-- | net/netfilter/nft_socket.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/net/netfilter/nft_socket.c b/net/netfilter/nft_socket.c new file mode 100644 index 000000000000..f28a0b944087 --- /dev/null +++ b/net/netfilter/nft_socket.c @@ -0,0 +1,144 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <linux/module.h> +#include <linux/netfilter/nf_tables.h> +#include <net/netfilter/nf_tables.h> +#include <net/netfilter/nf_tables_core.h> +#include <net/netfilter/nf_socket.h> +#include <net/inet_sock.h> +#include <net/tcp.h> + +struct nft_socket { + enum nft_socket_keys key:8; + union { + enum nft_registers dreg:8; + }; +}; + +static void nft_socket_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_socket *priv = nft_expr_priv(expr); + struct sk_buff *skb = pkt->skb; + struct sock *sk = skb->sk; + u32 *dest = ®s->data[priv->dreg]; + + if (!sk) + switch(nft_pf(pkt)) { + case NFPROTO_IPV4: + sk = nf_sk_lookup_slow_v4(nft_net(pkt), skb, nft_in(pkt)); + break; +#if IS_ENABLED(CONFIG_NF_SOCKET_IPV6) + case NFPROTO_IPV6: + sk = nf_sk_lookup_slow_v6(nft_net(pkt), skb, nft_in(pkt)); + break; +#endif + default: + WARN_ON_ONCE(1); + regs->verdict.code = NFT_BREAK; + return; + } + + if(!sk) { + nft_reg_store8(dest, 0); + return; + } + + /* So that subsequent socket matching not to require other lookups. */ + skb->sk = sk; + + switch(priv->key) { + case NFT_SOCKET_TRANSPARENT: + nft_reg_store8(dest, inet_sk_transparent(sk)); + break; + default: + WARN_ON(1); + regs->verdict.code = NFT_BREAK; + } +} + +static const struct nla_policy nft_socket_policy[NFTA_SOCKET_MAX + 1] = { + [NFTA_SOCKET_KEY] = { .type = NLA_U32 }, + [NFTA_SOCKET_DREG] = { .type = NLA_U32 }, +}; + +static int nft_socket_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_socket *priv = nft_expr_priv(expr); + unsigned int len; + + if (!tb[NFTA_SOCKET_DREG] || !tb[NFTA_SOCKET_KEY]) + return -EINVAL; + + switch(ctx->family) { + case NFPROTO_IPV4: +#if IS_ENABLED(CONFIG_NF_SOCKET_IPV6) + case NFPROTO_IPV6: +#endif + case NFPROTO_INET: + break; + default: + return -EOPNOTSUPP; + } + + priv->key = ntohl(nla_get_u32(tb[NFTA_SOCKET_KEY])); + switch(priv->key) { + case NFT_SOCKET_TRANSPARENT: + len = sizeof(u8); + break; + default: + return -EOPNOTSUPP; + } + + priv->dreg = nft_parse_register(tb[NFTA_SOCKET_DREG]); + return nft_validate_register_store(ctx, priv->dreg, NULL, + NFT_DATA_VALUE, len); +} + +static int nft_socket_dump(struct sk_buff *skb, + const struct nft_expr *expr) +{ + const struct nft_socket *priv = nft_expr_priv(expr); + + if (nla_put_u32(skb, NFTA_SOCKET_KEY, htonl(priv->key))) + return -1; + if (nft_dump_register(skb, NFTA_SOCKET_DREG, priv->dreg)) + return -1; + return 0; +} + +static struct nft_expr_type nft_socket_type; +static const struct nft_expr_ops nft_socket_ops = { + .type = &nft_socket_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_socket)), + .eval = nft_socket_eval, + .init = nft_socket_init, + .dump = nft_socket_dump, +}; + +static struct nft_expr_type nft_socket_type __read_mostly = { + .name = "socket", + .ops = &nft_socket_ops, + .policy = nft_socket_policy, + .maxattr = NFTA_SOCKET_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_socket_module_init(void) +{ + return nft_register_expr(&nft_socket_type); +} + +static void __exit nft_socket_module_exit(void) +{ + nft_unregister_expr(&nft_socket_type); +} + +module_init(nft_socket_module_init); +module_exit(nft_socket_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Máté Eckl"); +MODULE_DESCRIPTION("nf_tables socket match module"); |