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path: root/net/ipv4/netfilter/ipt_hashlimit.c
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Diffstat (limited to 'net/ipv4/netfilter/ipt_hashlimit.c')
-rw-r--r--net/ipv4/netfilter/ipt_hashlimit.c73
1 files changed, 22 insertions, 51 deletions
diff --git a/net/ipv4/netfilter/ipt_hashlimit.c b/net/ipv4/netfilter/ipt_hashlimit.c
index 7c6836c4646e..92980ab8ce48 100644
--- a/net/ipv4/netfilter/ipt_hashlimit.c
+++ b/net/ipv4/netfilter/ipt_hashlimit.c
@@ -28,9 +28,6 @@
#include <linux/jhash.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
-#include <linux/tcp.h>
-#include <linux/udp.h>
-#include <linux/sctp.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/list.h>
@@ -83,6 +80,7 @@ struct ipt_hashlimit_htable {
/* used internally */
spinlock_t lock; /* lock for list_head */
u_int32_t rnd; /* random seed for hash */
+ int rnd_initialized;
struct timer_list timer; /* timer for gc */
atomic_t count; /* number entries in table */
@@ -137,8 +135,10 @@ __dsthash_alloc_init(struct ipt_hashlimit_htable *ht, struct dsthash_dst *dst)
/* initialize hash with random val at the time we allocate
* the first hashtable entry */
- if (!ht->rnd)
+ if (!ht->rnd_initialized) {
get_random_bytes(&ht->rnd, 4);
+ ht->rnd_initialized = 1;
+ }
if (ht->cfg.max &&
atomic_read(&ht->count) >= ht->cfg.max) {
@@ -217,7 +217,7 @@ static int htable_create(struct ipt_hashlimit_info *minfo)
atomic_set(&hinfo->count, 0);
atomic_set(&hinfo->use, 1);
- hinfo->rnd = 0;
+ hinfo->rnd_initialized = 0;
spin_lock_init(&hinfo->lock);
hinfo->pde = create_proc_entry(minfo->name, 0, hashlimit_procdir);
if (!hinfo->pde) {
@@ -381,49 +381,6 @@ static inline void rateinfo_recalc(struct dsthash_ent *dh, unsigned long now)
dh->rateinfo.credit = dh->rateinfo.credit_cap;
}
-static inline int get_ports(const struct sk_buff *skb, int offset,
- u16 ports[2])
-{
- union {
- struct tcphdr th;
- struct udphdr uh;
- sctp_sctphdr_t sctph;
- } hdr_u, *ptr_u;
-
- /* Must not be a fragment. */
- if (offset)
- return 1;
-
- /* Must be big enough to read ports (both UDP and TCP have
- them at the start). */
- ptr_u = skb_header_pointer(skb, skb->nh.iph->ihl*4, 8, &hdr_u);
- if (!ptr_u)
- return 1;
-
- switch (skb->nh.iph->protocol) {
- case IPPROTO_TCP:
- ports[0] = ptr_u->th.source;
- ports[1] = ptr_u->th.dest;
- break;
- case IPPROTO_UDP:
- ports[0] = ptr_u->uh.source;
- ports[1] = ptr_u->uh.dest;
- break;
- case IPPROTO_SCTP:
- ports[0] = ptr_u->sctph.source;
- ports[1] = ptr_u->sctph.dest;
- break;
- default:
- /* all other protocols don't supprot per-port hash
- * buckets */
- ports[0] = ports[1] = 0;
- break;
- }
-
- return 0;
-}
-
-
static int
hashlimit_match(const struct sk_buff *skb,
const struct net_device *in,
@@ -449,8 +406,22 @@ hashlimit_match(const struct sk_buff *skb,
dst.src_ip = skb->nh.iph->saddr;
if (hinfo->cfg.mode & IPT_HASHLIMIT_HASH_DPT
||hinfo->cfg.mode & IPT_HASHLIMIT_HASH_SPT) {
- u_int16_t ports[2];
- if (get_ports(skb, offset, ports)) {
+ u_int16_t _ports[2], *ports;
+
+ switch (skb->nh.iph->protocol) {
+ case IPPROTO_TCP:
+ case IPPROTO_UDP:
+ case IPPROTO_SCTP:
+ case IPPROTO_DCCP:
+ ports = skb_header_pointer(skb, skb->nh.iph->ihl*4,
+ sizeof(_ports), &_ports);
+ break;
+ default:
+ _ports[0] = _ports[1] = 0;
+ ports = _ports;
+ break;
+ }
+ if (!ports) {
/* We've been asked to examine this packet, and we
can't. Hence, no choice but to drop. */
*hotdrop = 1;
@@ -561,7 +532,7 @@ static void
hashlimit_destroy(const struct xt_match *match, void *matchinfo,
unsigned int matchsize)
{
- struct ipt_hashlimit_info *r = (struct ipt_hashlimit_info *) matchinfo;
+ struct ipt_hashlimit_info *r = matchinfo;
htable_put(r->hinfo);
}