diff options
Diffstat (limited to 'net/netfilter/nft_numgen.c')
-rw-r--r-- | net/netfilter/nft_numgen.c | 80 |
1 files changed, 58 insertions, 22 deletions
diff --git a/net/netfilter/nft_numgen.c b/net/netfilter/nft_numgen.c index 48edb9d5f012..45d3dc9e96f2 100644 --- a/net/netfilter/nft_numgen.c +++ b/net/netfilter/nft_numgen.c @@ -9,16 +9,15 @@ #include <linux/netlink.h> #include <linux/netfilter.h> #include <linux/netfilter/nf_tables.h> +#include <linux/random.h> #include <linux/static_key.h> #include <net/netfilter/nf_tables.h> #include <net/netfilter/nf_tables_core.h> -static DEFINE_PER_CPU(struct rnd_state, nft_numgen_prandom_state); - struct nft_ng_inc { - enum nft_registers dreg:8; + u8 dreg; u32 modulus; - atomic_t counter; + atomic_t *counter; u32 offset; }; @@ -27,9 +26,9 @@ static u32 nft_ng_inc_gen(struct nft_ng_inc *priv) u32 nval, oval; do { - oval = atomic_read(&priv->counter); + oval = atomic_read(priv->counter); nval = (oval + 1 < priv->modulus) ? oval + 1 : 0; - } while (atomic_cmpxchg(&priv->counter, oval, nval) != oval); + } while (atomic_cmpxchg(priv->counter, oval, nval) != oval); return nval + priv->offset; } @@ -55,6 +54,7 @@ static int nft_ng_inc_init(const struct nft_ctx *ctx, const struct nlattr * const tb[]) { struct nft_ng_inc *priv = nft_expr_priv(expr); + int err; if (tb[NFTA_NG_OFFSET]) priv->offset = ntohl(nla_get_be32(tb[NFTA_NG_OFFSET])); @@ -66,11 +66,32 @@ static int nft_ng_inc_init(const struct nft_ctx *ctx, if (priv->offset + priv->modulus - 1 < priv->offset) return -EOVERFLOW; - priv->dreg = nft_parse_register(tb[NFTA_NG_DREG]); - atomic_set(&priv->counter, priv->modulus - 1); + priv->counter = kmalloc(sizeof(*priv->counter), GFP_KERNEL); + if (!priv->counter) + return -ENOMEM; + + atomic_set(priv->counter, priv->modulus - 1); - return nft_validate_register_store(ctx, priv->dreg, NULL, - NFT_DATA_VALUE, sizeof(u32)); + err = nft_parse_register_store(ctx, tb[NFTA_NG_DREG], &priv->dreg, + NULL, NFT_DATA_VALUE, sizeof(u32)); + if (err < 0) + goto err; + + return 0; +err: + kfree(priv->counter); + + return err; +} + +static bool nft_ng_inc_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + const struct nft_ng_inc *priv = nft_expr_priv(expr); + + nft_reg_track_cancel(track, priv->dreg, NFT_REG32_SIZE); + + return false; } static int nft_ng_dump(struct sk_buff *skb, enum nft_registers dreg, @@ -99,18 +120,23 @@ static int nft_ng_inc_dump(struct sk_buff *skb, const struct nft_expr *expr) priv->offset); } +static void nft_ng_inc_destroy(const struct nft_ctx *ctx, + const struct nft_expr *expr) +{ + const struct nft_ng_inc *priv = nft_expr_priv(expr); + + kfree(priv->counter); +} + struct nft_ng_random { - enum nft_registers dreg:8; + u8 dreg; u32 modulus; u32 offset; }; -static u32 nft_ng_random_gen(struct nft_ng_random *priv) +static u32 nft_ng_random_gen(const struct nft_ng_random *priv) { - struct rnd_state *state = this_cpu_ptr(&nft_numgen_prandom_state); - - return reciprocal_scale(prandom_u32_state(state), priv->modulus) + - priv->offset; + return reciprocal_scale(get_random_u32(), priv->modulus) + priv->offset; } static void nft_ng_random_eval(const struct nft_expr *expr, @@ -138,12 +164,8 @@ static int nft_ng_random_init(const struct nft_ctx *ctx, if (priv->offset + priv->modulus - 1 < priv->offset) return -EOVERFLOW; - prandom_init_once(&nft_numgen_prandom_state); - - priv->dreg = nft_parse_register(tb[NFTA_NG_DREG]); - - return nft_validate_register_store(ctx, priv->dreg, NULL, - NFT_DATA_VALUE, sizeof(u32)); + return nft_parse_register_store(ctx, tb[NFTA_NG_DREG], &priv->dreg, + NULL, NFT_DATA_VALUE, sizeof(u32)); } static int nft_ng_random_dump(struct sk_buff *skb, const struct nft_expr *expr) @@ -154,13 +176,25 @@ static int nft_ng_random_dump(struct sk_buff *skb, const struct nft_expr *expr) priv->offset); } +static bool nft_ng_random_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + const struct nft_ng_random *priv = nft_expr_priv(expr); + + nft_reg_track_cancel(track, priv->dreg, NFT_REG32_SIZE); + + return false; +} + static struct nft_expr_type nft_ng_type; static const struct nft_expr_ops nft_ng_inc_ops = { .type = &nft_ng_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_ng_inc)), .eval = nft_ng_inc_eval, .init = nft_ng_inc_init, + .destroy = nft_ng_inc_destroy, .dump = nft_ng_inc_dump, + .reduce = nft_ng_inc_reduce, }; static const struct nft_expr_ops nft_ng_random_ops = { @@ -169,6 +203,7 @@ static const struct nft_expr_ops nft_ng_random_ops = { .eval = nft_ng_random_eval, .init = nft_ng_random_init, .dump = nft_ng_random_dump, + .reduce = nft_ng_random_reduce, }; static const struct nft_expr_ops * @@ -217,3 +252,4 @@ module_exit(nft_ng_module_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Laura Garcia <nevola@gmail.com>"); MODULE_ALIAS_NFT_EXPR("numgen"); +MODULE_DESCRIPTION("nftables number generator module"); |