| 1 | --- a/include/linux/netfilter/xt_recent.h |
| 2 | +++ b/include/linux/netfilter/xt_recent.h |
| 3 | @@ -9,6 +9,7 @@ enum { |
| 4 | XT_RECENT_UPDATE = 1 << 2, |
| 5 | XT_RECENT_REMOVE = 1 << 3, |
| 6 | XT_RECENT_TTL = 1 << 4, |
| 7 | + XT_RECENT_REAP = 1 << 5, |
| 8 | |
| 9 | XT_RECENT_SOURCE = 0, |
| 10 | XT_RECENT_DEST = 1, |
| 11 | @@ -16,6 +17,9 @@ enum { |
| 12 | XT_RECENT_NAME_LEN = 200, |
| 13 | }; |
| 14 | |
| 15 | +/* Only allowed with --rcheck and --update */ |
| 16 | +#define XT_RECENT_MODIFIERS (XT_RECENT_TTL|XT_RECENT_REAP) |
| 17 | + |
| 18 | struct xt_recent_mtinfo { |
| 19 | __u32 seconds; |
| 20 | __u32 hit_count; |
| 21 | --- a/net/netfilter/xt_recent.c |
| 22 | +++ b/net/netfilter/xt_recent.c |
| 23 | @@ -142,6 +142,25 @@ static void recent_entry_remove(struct r |
| 24 | t->entries--; |
| 25 | } |
| 26 | |
| 27 | +/* |
| 28 | + * Drop entries with timestamps older then 'time'. |
| 29 | + */ |
| 30 | +static void recent_entry_reap(struct recent_table *t, unsigned long time) |
| 31 | +{ |
| 32 | + struct recent_entry *e; |
| 33 | + |
| 34 | + /* |
| 35 | + * The head of the LRU list is always the oldest entry. |
| 36 | + */ |
| 37 | + e = list_entry(t->lru_list.next, struct recent_entry, lru_list); |
| 38 | + |
| 39 | + /* |
| 40 | + * The last time stamp is the most recent. |
| 41 | + */ |
| 42 | + if (time_after(time, e->stamps[e->index-1])) |
| 43 | + recent_entry_remove(t, e); |
| 44 | +} |
| 45 | + |
| 46 | static struct recent_entry * |
| 47 | recent_entry_init(struct recent_table *t, const union nf_inet_addr *addr, |
| 48 | u_int16_t family, u_int8_t ttl) |
| 49 | @@ -265,6 +284,10 @@ recent_mt(const struct sk_buff *skb, con |
| 50 | break; |
| 51 | } |
| 52 | } |
| 53 | + |
| 54 | + /* info->seconds must be non-zero */ |
| 55 | + if (info->check_set & XT_RECENT_REAP) |
| 56 | + recent_entry_reap(t, time); |
| 57 | } |
| 58 | |
| 59 | if (info->check_set & XT_RECENT_SET || |
| 60 | @@ -292,7 +315,10 @@ static bool recent_mt_check(const struct |
| 61 | XT_RECENT_CHECK | XT_RECENT_UPDATE)) != 1) |
| 62 | return false; |
| 63 | if ((info->check_set & (XT_RECENT_SET | XT_RECENT_REMOVE)) && |
| 64 | - (info->seconds || info->hit_count)) |
| 65 | + (info->seconds || info->hit_count || |
| 66 | + (info->check_set & XT_RECENT_MODIFIERS))) |
| 67 | + return false; |
| 68 | + if ((info->check_set & XT_RECENT_REAP) && !info->seconds) |
| 69 | return false; |
| 70 | if (info->hit_count > ip_pkt_list_tot) |
| 71 | return false; |
| 72 | |
