static DEFINE_SPINLOCK(limit_lock);
struct nft_limit {
+ u64 last;
u64 tokens;
+ u64 tokens_max;
u64 rate;
- u64 unit;
- unsigned long stamp;
+ u64 nsecs;
+ u32 burst;
};
-static void nft_limit_eval(const struct nft_expr *expr,
- struct nft_regs *regs,
- const struct nft_pktinfo *pkt)
+static inline bool nft_limit_eval(struct nft_limit *limit, u64 cost)
{
- struct nft_limit *priv = nft_expr_priv(expr);
+ u64 now, tokens;
+ s64 delta;
spin_lock_bh(&limit_lock);
- if (time_after_eq(jiffies, priv->stamp)) {
- priv->tokens = priv->rate;
- priv->stamp = jiffies + priv->unit * HZ;
- }
-
- if (priv->tokens >= 1) {
- priv->tokens--;
+ now = ktime_get_ns();
+ tokens = limit->tokens + now - limit->last;
+ if (tokens > limit->tokens_max)
+ tokens = limit->tokens_max;
+
+ limit->last = now;
+ delta = tokens - cost;
+ if (delta >= 0) {
+ limit->tokens = delta;
spin_unlock_bh(&limit_lock);
- return;
+ return false;
}
+ limit->tokens = tokens;
spin_unlock_bh(&limit_lock);
-
- regs->verdict.code = NFT_BREAK;
+ return true;
}
-static const struct nla_policy nft_limit_policy[NFTA_LIMIT_MAX + 1] = {
- [NFTA_LIMIT_RATE] = { .type = NLA_U64 },
- [NFTA_LIMIT_UNIT] = { .type = NLA_U64 },
-};
-
-static int nft_limit_init(const struct nft_ctx *ctx,
- const struct nft_expr *expr,
+static int nft_limit_init(struct nft_limit *limit,
const struct nlattr * const tb[])
{
- struct nft_limit *priv = nft_expr_priv(expr);
+ u64 unit;
if (tb[NFTA_LIMIT_RATE] == NULL ||
tb[NFTA_LIMIT_UNIT] == NULL)
return -EINVAL;
- priv->rate = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_RATE]));
- priv->unit = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_UNIT]));
- priv->stamp = jiffies + priv->unit * HZ;
- priv->tokens = priv->rate;
+ limit->rate = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_RATE]));
+ unit = be64_to_cpu(nla_get_be64(tb[NFTA_LIMIT_UNIT]));
+ limit->nsecs = unit * NSEC_PER_SEC;
+ if (limit->rate == 0 || limit->nsecs < unit)
+ return -EOVERFLOW;
+ limit->tokens = limit->tokens_max = limit->nsecs;
+
+ if (tb[NFTA_LIMIT_BURST]) {
+ u64 rate;
+
+ limit->burst = ntohl(nla_get_be32(tb[NFTA_LIMIT_BURST]));
+
+ rate = limit->rate + limit->burst;
+ if (rate < limit->rate)
+ return -EOVERFLOW;
+
+ limit->rate = rate;
+ }
+ limit->last = ktime_get_ns();
+
return 0;
}
-static int nft_limit_dump(struct sk_buff *skb, const struct nft_expr *expr)
+static int nft_limit_dump(struct sk_buff *skb, const struct nft_limit *limit,
+ enum nft_limit_type type)
{
- const struct nft_limit *priv = nft_expr_priv(expr);
+ u64 secs = div_u64(limit->nsecs, NSEC_PER_SEC);
+ u64 rate = limit->rate - limit->burst;
- if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(priv->rate)))
- goto nla_put_failure;
- if (nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(priv->unit)))
+ if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(rate)) ||
+ nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(secs)) ||
+ nla_put_be32(skb, NFTA_LIMIT_BURST, htonl(limit->burst)) ||
+ nla_put_be32(skb, NFTA_LIMIT_TYPE, htonl(type)))
goto nla_put_failure;
return 0;
return -1;
}
+struct nft_limit_pkts {
+ struct nft_limit limit;
+ u64 cost;
+};
+
+static void nft_limit_pkts_eval(const struct nft_expr *expr,
+ struct nft_regs *regs,
+ const struct nft_pktinfo *pkt)
+{
+ struct nft_limit_pkts *priv = nft_expr_priv(expr);
+
+ if (nft_limit_eval(&priv->limit, priv->cost))
+ regs->verdict.code = NFT_BREAK;
+}
+
+static const struct nla_policy nft_limit_policy[NFTA_LIMIT_MAX + 1] = {
+ [NFTA_LIMIT_RATE] = { .type = NLA_U64 },
+ [NFTA_LIMIT_UNIT] = { .type = NLA_U64 },
+ [NFTA_LIMIT_BURST] = { .type = NLA_U32 },
+ [NFTA_LIMIT_TYPE] = { .type = NLA_U32 },
+};
+
+static int nft_limit_pkts_init(const struct nft_ctx *ctx,
+ const struct nft_expr *expr,
+ const struct nlattr * const tb[])
+{
+ struct nft_limit_pkts *priv = nft_expr_priv(expr);
+ int err;
+
+ err = nft_limit_init(&priv->limit, tb);
+ if (err < 0)
+ return err;
+
+ priv->cost = div_u64(priv->limit.nsecs, priv->limit.rate);
+ return 0;
+}
+
+static int nft_limit_pkts_dump(struct sk_buff *skb, const struct nft_expr *expr)
+{
+ const struct nft_limit_pkts *priv = nft_expr_priv(expr);
+
+ return nft_limit_dump(skb, &priv->limit, NFT_LIMIT_PKTS);
+}
+
static struct nft_expr_type nft_limit_type;
-static const struct nft_expr_ops nft_limit_ops = {
+static const struct nft_expr_ops nft_limit_pkts_ops = {
+ .type = &nft_limit_type,
+ .size = NFT_EXPR_SIZE(sizeof(struct nft_limit_pkts)),
+ .eval = nft_limit_pkts_eval,
+ .init = nft_limit_pkts_init,
+ .dump = nft_limit_pkts_dump,
+};
+
+static void nft_limit_pkt_bytes_eval(const struct nft_expr *expr,
+ struct nft_regs *regs,
+ const struct nft_pktinfo *pkt)
+{
+ struct nft_limit *priv = nft_expr_priv(expr);
+ u64 cost = div_u64(priv->nsecs * pkt->skb->len, priv->rate);
+
+ if (nft_limit_eval(priv, cost))
+ regs->verdict.code = NFT_BREAK;
+}
+
+static int nft_limit_pkt_bytes_init(const struct nft_ctx *ctx,
+ const struct nft_expr *expr,
+ const struct nlattr * const tb[])
+{
+ struct nft_limit *priv = nft_expr_priv(expr);
+
+ return nft_limit_init(priv, tb);
+}
+
+static int nft_limit_pkt_bytes_dump(struct sk_buff *skb,
+ const struct nft_expr *expr)
+{
+ const struct nft_limit *priv = nft_expr_priv(expr);
+
+ return nft_limit_dump(skb, priv, NFT_LIMIT_PKT_BYTES);
+}
+
+static const struct nft_expr_ops nft_limit_pkt_bytes_ops = {
.type = &nft_limit_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_limit)),
- .eval = nft_limit_eval,
- .init = nft_limit_init,
- .dump = nft_limit_dump,
+ .eval = nft_limit_pkt_bytes_eval,
+ .init = nft_limit_pkt_bytes_init,
+ .dump = nft_limit_pkt_bytes_dump,
};
+static const struct nft_expr_ops *
+nft_limit_select_ops(const struct nft_ctx *ctx,
+ const struct nlattr * const tb[])
+{
+ if (tb[NFTA_LIMIT_TYPE] == NULL)
+ return &nft_limit_pkts_ops;
+
+ switch (ntohl(nla_get_be32(tb[NFTA_LIMIT_TYPE]))) {
+ case NFT_LIMIT_PKTS:
+ return &nft_limit_pkts_ops;
+ case NFT_LIMIT_PKT_BYTES:
+ return &nft_limit_pkt_bytes_ops;
+ }
+ return ERR_PTR(-EOPNOTSUPP);
+}
+
static struct nft_expr_type nft_limit_type __read_mostly = {
.name = "limit",
- .ops = &nft_limit_ops,
+ .select_ops = nft_limit_select_ops,
.policy = nft_limit_policy,
.maxattr = NFTA_LIMIT_MAX,
.flags = NFT_EXPR_STATEFUL,
Code Review / kvmfornfv.git / blobdiff