From c3e1b005ed1cc068fc9d454a6e745830d55d251d Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Thu, 26 Mar 2015 12:39:37 +0000 Subject: [PATCH] netfilter: nf_tables: add set element timeout support Add API support for set element timeouts. Elements can have a individual timeout value specified, overriding the sets' default. Two new extension types are used for timeouts - the timeout value and the expiration time. The timeout value only exists if it differs from the default value. Signed-off-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_tables.h | 20 ++++++++++++ include/uapi/linux/netfilter/nf_tables.h | 4 +++ net/netfilter/nf_tables_api.c | 53 ++++++++++++++++++++++++++++++-- 3 files changed, 75 insertions(+), 2 deletions(-) diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 8936803..f2726c5 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -329,12 +329,16 @@ void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set, * @NFT_SET_EXT_KEY: element key * @NFT_SET_EXT_DATA: mapping data * @NFT_SET_EXT_FLAGS: element flags + * @NFT_SET_EXT_TIMEOUT: element timeout + * @NFT_SET_EXT_EXPIRATION: element expiration time * @NFT_SET_EXT_NUM: number of extension types */ enum nft_set_extensions { NFT_SET_EXT_KEY, NFT_SET_EXT_DATA, NFT_SET_EXT_FLAGS, + NFT_SET_EXT_TIMEOUT, + NFT_SET_EXT_EXPIRATION, NFT_SET_EXT_NUM }; @@ -431,6 +435,22 @@ static inline u8 *nft_set_ext_flags(const struct nft_set_ext *ext) return nft_set_ext(ext, NFT_SET_EXT_FLAGS); } +static inline u64 *nft_set_ext_timeout(const struct nft_set_ext *ext) +{ + return nft_set_ext(ext, NFT_SET_EXT_TIMEOUT); +} + +static inline unsigned long *nft_set_ext_expiration(const struct nft_set_ext *ext) +{ + return nft_set_ext(ext, NFT_SET_EXT_EXPIRATION); +} + +static inline bool nft_set_elem_expired(const struct nft_set_ext *ext) +{ + return nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION) && + time_is_before_eq_jiffies(*nft_set_ext_expiration(ext)); +} + static inline struct nft_set_ext *nft_set_elem_ext(const struct nft_set *set, void *elem) { diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 971d245..83441cc 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -290,12 +290,16 @@ enum nft_set_elem_flags { * @NFTA_SET_ELEM_KEY: key value (NLA_NESTED: nft_data) * @NFTA_SET_ELEM_DATA: data value of mapping (NLA_NESTED: nft_data_attributes) * @NFTA_SET_ELEM_FLAGS: bitmask of nft_set_elem_flags (NLA_U32) + * @NFTA_SET_ELEM_TIMEOUT: timeout value (NLA_U64) + * @NFTA_SET_ELEM_EXPIRATION: expiration time (NLA_U64) */ enum nft_set_elem_attributes { NFTA_SET_ELEM_UNSPEC, NFTA_SET_ELEM_KEY, NFTA_SET_ELEM_DATA, NFTA_SET_ELEM_FLAGS, + NFTA_SET_ELEM_TIMEOUT, + NFTA_SET_ELEM_EXPIRATION, __NFTA_SET_ELEM_MAX }; #define NFTA_SET_ELEM_MAX (__NFTA_SET_ELEM_MAX - 1) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 6320b64e..9e032db 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -2863,6 +2863,14 @@ const struct nft_set_ext_type nft_set_ext_types[] = { .len = sizeof(u8), .align = __alignof__(u8), }, + [NFT_SET_EXT_TIMEOUT] = { + .len = sizeof(u64), + .align = __alignof__(u64), + }, + [NFT_SET_EXT_EXPIRATION] = { + .len = sizeof(unsigned long), + .align = __alignof__(unsigned long), + }, }; EXPORT_SYMBOL_GPL(nft_set_ext_types); @@ -2874,6 +2882,7 @@ static const struct nla_policy nft_set_elem_policy[NFTA_SET_ELEM_MAX + 1] = { [NFTA_SET_ELEM_KEY] = { .type = NLA_NESTED }, [NFTA_SET_ELEM_DATA] = { .type = NLA_NESTED }, [NFTA_SET_ELEM_FLAGS] = { .type = NLA_U32 }, + [NFTA_SET_ELEM_TIMEOUT] = { .type = NLA_U64 }, }; static const struct nla_policy nft_set_elem_list_policy[NFTA_SET_ELEM_LIST_MAX + 1] = { @@ -2935,6 +2944,25 @@ static int nf_tables_fill_setelem(struct sk_buff *skb, htonl(*nft_set_ext_flags(ext)))) goto nla_put_failure; + if (nft_set_ext_exists(ext, NFT_SET_EXT_TIMEOUT) && + nla_put_be64(skb, NFTA_SET_ELEM_TIMEOUT, + cpu_to_be64(*nft_set_ext_timeout(ext)))) + goto nla_put_failure; + + if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION)) { + unsigned long expires, now = jiffies; + + expires = *nft_set_ext_expiration(ext); + if (time_before(now, expires)) + expires -= now; + else + expires = 0; + + if (nla_put_be64(skb, NFTA_SET_ELEM_EXPIRATION, + cpu_to_be64(jiffies_to_msecs(expires)))) + goto nla_put_failure; + } + nla_nest_end(skb, nest); return 0; @@ -3158,7 +3186,7 @@ static void *nft_set_elem_init(const struct nft_set *set, const struct nft_set_ext_tmpl *tmpl, const struct nft_data *key, const struct nft_data *data, - gfp_t gfp) + u64 timeout, gfp_t gfp) { struct nft_set_ext *ext; void *elem; @@ -3173,6 +3201,11 @@ static void *nft_set_elem_init(const struct nft_set *set, memcpy(nft_set_ext_key(ext), key, set->klen); if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA)) memcpy(nft_set_ext_data(ext), data, set->dlen); + if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION)) + *nft_set_ext_expiration(ext) = + jiffies + msecs_to_jiffies(timeout); + if (nft_set_ext_exists(ext, NFT_SET_EXT_TIMEOUT)) + *nft_set_ext_timeout(ext) = timeout; return elem; } @@ -3201,6 +3234,7 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, struct nft_data data; enum nft_registers dreg; struct nft_trans *trans; + u64 timeout; u32 flags; int err; @@ -3241,6 +3275,15 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, return -EINVAL; } + timeout = 0; + if (nla[NFTA_SET_ELEM_TIMEOUT] != NULL) { + if (!(set->flags & NFT_SET_TIMEOUT)) + return -EINVAL; + timeout = be64_to_cpu(nla_get_be64(nla[NFTA_SET_ELEM_TIMEOUT])); + } else if (set->flags & NFT_SET_TIMEOUT) { + timeout = set->timeout; + } + err = nft_data_init(ctx, &elem.key, &d1, nla[NFTA_SET_ELEM_KEY]); if (err < 0) goto err1; @@ -3249,6 +3292,11 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, goto err2; nft_set_ext_add(&tmpl, NFT_SET_EXT_KEY); + if (timeout > 0) { + nft_set_ext_add(&tmpl, NFT_SET_EXT_EXPIRATION); + if (timeout != set->timeout) + nft_set_ext_add(&tmpl, NFT_SET_EXT_TIMEOUT); + } if (nla[NFTA_SET_ELEM_DATA] != NULL) { err = nft_data_init(ctx, &data, &d2, nla[NFTA_SET_ELEM_DATA]); @@ -3277,7 +3325,8 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set, } err = -ENOMEM; - elem.priv = nft_set_elem_init(set, &tmpl, &elem.key, &data, GFP_KERNEL); + elem.priv = nft_set_elem_init(set, &tmpl, &elem.key, &data, + timeout, GFP_KERNEL); if (elem.priv == NULL) goto err3; -- 2.7.4