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* IPv6 fragment reassembly for connection tracking
*
* Copyright (C)2004 USAGI/WIDE Project
*
* Author:
* Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
*
* Based on: net/ipv6/reassembly.c
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/config.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/jiffies.h>
#include <linux/net.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/in6.h>
#include <linux/ipv6.h>
#include <linux/icmpv6.h>
#include <linux/random.h>
#include <linux/jhash.h>
#include <net/sock.h>
#include <net/snmp.h>
#include <net/ipv6.h>
#include <net/protocol.h>
#include <net/transp_v6.h>
#include <net/rawv6.h>
#include <net/ndisc.h>
#include <net/addrconf.h>
#include <linux/sysctl.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <linux/kernel.h>
#include <linux/module.h>
#if 0
#define DEBUGP printk
#else
#define DEBUGP(format, args...)
#endif
#define NF_CT_FRAG6_HIGH_THRESH 262144 /* == 256*1024 */
#define NF_CT_FRAG6_LOW_THRESH 196608 /* == 192*1024 */
#define NF_CT_FRAG6_TIMEOUT IPV6_FRAG_TIMEOUT
unsigned int nf_ct_frag6_high_thresh = 256*1024;
unsigned int nf_ct_frag6_low_thresh = 192*1024;
unsigned long nf_ct_frag6_timeout = IPV6_FRAG_TIMEOUT;
struct nf_ct_frag6_skb_cb
{
struct inet6_skb_parm h;
int offset;
struct sk_buff *orig;
};
#define NFCT_FRAG6_CB(skb) ((struct nf_ct_frag6_skb_cb*)((skb)->cb))
struct nf_ct_frag6_queue
{
struct hlist_node list;
struct list_head lru_list; /* lru list member */
__u32 id; /* fragment id */
struct in6_addr saddr;
struct in6_addr daddr;
spinlock_t lock;
atomic_t refcnt;
struct timer_list timer; /* expire timer */
struct sk_buff *fragments;
int len;
int meat;
struct timeval stamp;
unsigned int csum;
__u8 last_in; /* has first/last segment arrived? */
#define COMPLETE 4
#define FIRST_IN 2
#define LAST_IN 1
__u16 nhoffset;
};
/* Hash table. */
#define FRAG6Q_HASHSZ 64
static struct hlist_head nf_ct_frag6_hash[FRAG6Q_HASHSZ];
static DEFINE_RWLOCK(nf_ct_frag6_lock);
static u32 nf_ct_frag6_hash_rnd;
static LIST_HEAD(nf_ct_frag6_lru_list);
int nf_ct_frag6_nqueues = 0;
static __inline__ void __fq_unlink(struct nf_ct_frag6_queue *fq)
{
hlist_del(&fq->list);
list_del(&fq->lru_list);
nf_ct_frag6_nqueues--;
}
static __inline__ void fq_unlink(struct nf_ct_frag6_queue *fq)
{
write_lock(&nf_ct_frag6_lock);
__fq_unlink(fq);
write_unlock(&nf_ct_frag6_lock);
}
static unsigned int ip6qhashfn(u32 id, struct in6_addr *saddr,
struct in6_addr *daddr)
{
u32 a, b, c;
a = saddr->s6_addr32[0];
b = saddr->s6_addr32[1];
c = saddr->s6_addr32[2];
a += JHASH_GOLDEN_RATIO;
b += JHASH_GOLDEN_RATIO;
c += nf_ct_frag6_hash_rnd;
__jhash_mix(a, b, c);
a += saddr->s6_addr32[3];
b += daddr->s6_addr32[0];
c += daddr->s6_addr32[1];
__jhash_mix(a, b, c);
a += daddr->s6_addr32[2];
b += daddr->s6_addr32[3];
c += id;
__jhash_mix(a, b, c);
return c & (FRAG6Q_HASHSZ - 1);
}
static struct timer_list nf_ct_frag6_secret_timer;
int nf_ct_frag6_secret_interval = 10 * 60 * HZ;
static void nf_ct_frag6_secret_rebuild(unsigned long dummy)
{
unsigned long now = jiffies;
int i;
write_lock(&nf_ct_frag6_lock);
get_random_bytes(&nf_ct_frag6_hash_rnd, sizeof(u32));
for (i = 0; i < FRAG6Q_HASHSZ; i++) {
struct nf_ct_frag6_queue *q;
struct hlist_node *p, *n;
hlist_for_each_entry_safe(q, p, n, &nf_ct_frag6_hash[i], list) {
unsigned int hval = ip6qhashfn(q->id,
&q->saddr,
&q->daddr);
if (hval != i) {
hlist_del(&q->list);
/* Relink to new hash chain. */
hlist_add_head(&q->list,
&nf_ct_frag6_hash[hval]);
}
}
}
write_unlock(&nf_ct_frag6_lock);
mod_timer(&nf_ct_frag6_secret_timer, now + nf_ct_frag6_secret_interval);
}
atomic_t nf_ct_frag6_mem = ATOMIC_INIT(0);
/* Memory Tracking Functions. */
static inline void frag_kfree_skb(struct sk_buff *skb, unsigned int *work)
{
if (work)
*work -= skb->truesize;
atomic_sub(skb->truesize, &nf_ct_frag6_mem);
if (NFCT_FRAG6_CB(skb)->orig)
kfree_skb(NFCT_FRAG6_CB(skb)->orig);
kfree_skb(skb);
}
static inline void frag_free_queue(struct nf_ct_frag6_queue *fq,
unsigned int *work)
{
if (work)
*work -= sizeof(struct nf_ct_frag6_queue);
atomic_sub(sizeof(struct nf_ct_frag6_queue), &nf_ct_frag6_mem);
kfree(fq);
}
static inline struct nf_ct_frag6_queue *frag_alloc_queue(void)
{
struct nf_ct_frag6_queue *fq = kmalloc(sizeof(struct nf_ct_frag6_queue), GFP_ATOMIC);
if (!fq)
return NULL;
atomic_add(sizeof(struct nf_ct_frag6_queue), &nf_ct_frag6_mem);
return fq;
}
/* Destruction primitives. */
/* Complete destruction of fq. */
static void nf_ct_frag6_destroy(struct nf_ct_frag6_queue *fq,
unsigned int *work)
{
struct sk_buff *fp;
BUG_TRAP(fq->last_in&COMPLETE);
BUG_TRAP(del_timer(&fq->timer) == 0);
/* Release all fragment data. */
fp = fq->fragments;
while (fp) {
struct sk_buff *xp = fp->next;
frag_kfree_skb(fp, work);
fp = xp;
}
frag_free_queue(fq, work);
}
static __inline__ void fq_put(struct nf_ct_frag6_queue *fq, unsigned int *work)
{
if (atomic_dec_and_test(&fq->refcnt))
nf_ct_frag6_destroy(fq, work);
}
/* Kill fq entry. It is not destroyed immediately,
* because caller (and someone more) holds reference count.
*/
static __inline__ void fq_kill(struct nf_ct_frag6_queue *fq)
{
if (del_timer(&fq->timer))
atomic_dec(&fq->refcnt);
if (!(fq->last_in & COMPLETE)) {
fq_unlink(fq);
atomic_dec(&fq->refcnt);
fq->last_in |= COMPLETE;
}
}
static void nf_ct_frag6_evictor(void)
{
struct nf_ct_frag6_queue *fq;
struct list_head *tmp;
unsigned int work;
work = atomic_read(&nf_ct_frag6_mem);
if (work <= nf_ct_frag6_low_thresh)
return;
work -= nf_ct_frag6_low_thresh;
while (work > 0) {
read_lock(&nf_ct_frag6_lock);
if (list_empty(&nf_ct_frag6_lru_list)) {
read_unlock(&nf_ct_frag6_lock);
return;
}
tmp = nf_ct_frag6_lru_list.next;
BUG_ON(tmp == NULL);
fq = list_entry(tmp, struct nf_ct_frag6_queue, lru_list);
atomic_inc(&fq->refcnt);
read_unlock(&nf_ct_frag6_lock);
spin_lock(&fq->lock);
if (!(fq->last_in&COMPLETE))
fq_kill(fq);
spin_unlock(&fq->lock);
fq_put(fq, &work);
}
}
static void nf_ct_frag6_expire(unsigned long data)
{
struct nf_ct_frag6_queue *fq = (struct nf_ct_frag6_queue *) data;
spin_lock(&fq->lock);
if (fq->last_in & COMPLETE)
goto out;
fq_kill(fq);
out:
spin_unlock(&fq->lock);
fq_put(fq, NULL);
}
/* Creation primitives. */
static struct nf_ct_frag6_queue *nf_ct_frag6_intern(unsigned int hash,
struct nf_ct_frag6_queue *fq_in)
{
struct nf_ct_frag6_queue *fq;
#ifdef CONFIG_SMP
struct hlist_node *n;
#endif
write_lock(&nf_ct_frag6_lock);
#ifdef CONFIG_SMP
hlist_for_each_entry(fq, n, &nf_ct_frag6_hash[hash], list) {
if (fq->id == fq_in->id &&
!ipv6_addr_cmp(&fq_in->saddr, &fq->saddr) &&
!ipv6_addr_cmp(&fq_in->daddr, &fq->daddr)) {
atomic_inc(&fq->refcnt);
write_unlock(&nf_ct_frag6_lock);
fq_in->last_in |= COMPLETE;
fq_put(fq_in, NULL);
return fq;
}
}
#endif
fq = fq_in;
if (!mod_timer(&fq->timer, jiffies + nf_ct_frag6_timeout))
atomic_inc(&fq->refcnt);
atomic_inc(&fq->refcnt);
hlist_add_head(&fq->list, &nf_ct_frag6_hash[hash]);
INIT_LIST_HEAD(&fq->lru_list);
list_add_tail(&fq->lru_list, &nf_ct_frag6_lru_list);
nf_ct_frag6_nqueues++;
write_unlock(&nf_ct_frag6_lock);
return fq;
}
static struct nf_ct_frag6_queue *
nf_ct_frag6_create(unsigned int hash, u32 id, struct in6_addr *src, struct in6_addr *dst)
{
struct nf_ct_frag6_queue *fq;
if ((fq = frag_alloc_queue()) == NULL) {
DEBUGP("Can't alloc new queue\n");
goto oom;
}
memset(fq, 0, sizeof(struct nf_ct_frag6_queue));
fq->id = id;
ipv6_addr_copy(&fq->saddr, src);
ipv6_addr_copy(&fq->daddr, dst);
init_timer(&fq->timer);
fq->timer.function = nf_ct_frag6_expire;
fq->timer.data = (long) fq;
spin_lock_init(&fq->lock);
atomic_set(&fq->refcnt, 1);
return nf_ct_frag6_intern(hash, fq);
oom:
return NULL;
}
static __inline__ struct nf_ct_frag6_queue *
fq_find(u32 id, struct in6_addr *src, struct in6_addr *dst)
{
struct nf_ct_frag6_queue *fq;
struct hlist_node *n;
unsigned int hash = ip6qhashfn(id, src, dst);
read_lock(&nf_ct_frag6_lock);
hlist_for_each_entry(fq, n, &nf_ct_frag6_hash[hash], list) {
if (fq->id == id &&
!ipv6_addr_cmp(src, &fq->saddr) &&
!ipv6_addr_cmp(dst, &fq->daddr)) {
atomic_inc(&fq->refcnt);
read_unlock(&nf_ct_frag6_lock);
return fq;
}
}
read_unlock(&nf_ct_frag6_lock);
return nf_ct_frag6_create(hash, id, src, dst);
}
static int nf_ct_frag6_queue(struct nf_ct_frag6_queue *fq, struct sk_buff *skb,
struct frag_hdr *fhdr, int nhoff)
{
struct sk_buff *prev, *next;
int offset, end;
if (fq->last_in & COMPLETE) {
DEBUGP("Allready completed\n");
goto err;
}
offset = ntohs(fhdr->frag_off) & ~0x7;
end = offset + (ntohs(skb->nh.ipv6h->payload_len) -
((u8 *) (fhdr + 1) - (u8 *) (skb->nh.ipv6h + 1)));
if ((unsigned int)end > IPV6_MAXPLEN) {
DEBUGP("offset is too large.\n");
return -1;
}
if (skb->ip_summed == CHECKSUM_HW)
skb->csum = csum_sub(skb->csum,
csum_partial(skb->nh.raw,
(u8*)(fhdr + 1) - skb->nh.raw,
0));
/* Is this the final fragment? */
if (!(fhdr->frag_off & htons(IP6_MF))) {
/* If we already have some bits beyond end
* or have different end, the segment is corrupted.
*/
if (end < fq->len ||
((fq->last_in & LAST_IN) && end != fq->len)) {
DEBUGP("already received last fragment\n");
goto err;
}
fq->last_in |= LAST_IN;
fq->len = end;
} else {
/* Check if the fragment is rounded to 8 bytes.
* Required by the RFC.
*/
if (end & 0x7) {
/* RFC2460 says always send parameter problem in
* this case. -DaveM
*/
DEBUGP("the end of this fragment is not rounded to 8 bytes.\n");
return -1;
}
if (end > fq->len) {
/* Some bits beyond end -> corruption. */
if (fq->last_in & LAST_IN) {
DEBUGP("last packet already reached.\n");
goto err;
}
fq->len = end;
}
}
if (end == offset)
goto err;
/* Point into the IP datagram 'data' part. */
if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) {
DEBUGP("queue: message is too short.\n");
goto err;
}
if (end-offset < skb->len) {
if (pskb_trim(skb, end - offset)) {
DEBUGP("Can't trim\n");
goto err;
}
if (skb->ip_summed != CHECKSUM_UNNECESSARY)
skb->ip_summed = CHECKSUM_NONE;
}
/* Find out which fragments are in front and at the back of us
* in the chain of fragments so far. We must know where to put
* this fragment, right?
*/
prev = NULL;
for (next = fq->fragments; next != NULL; next = next->next) {
if (NFCT_FRAG6_CB(next)->offset >= offset)
break; /* bingo! */
prev = next;
}
/* We found where to put this one. Check for overlap with
* preceding fragment, and, if needed, align things so that
* any overlaps are eliminated.
*/
if (prev) {
int i = (NFCT_FRAG6_CB(prev)->offset + prev->len) - offset;
if (i > 0) {
offset += i;
if (end <= offset) {
DEBUGP("overlap\n");
goto err;
}
if (!pskb_pull(skb, i)) {
DEBUGP("Can't pull\n");
goto err;
}
if (skb->ip_summed != CHECKSUM_UNNECESSARY)
skb->ip_summed = CHECKSUM_NONE;
}
}
/* Look for overlap with succeeding segments.
* If we can merge fragments, do it.
*/
while (next && NFCT_FRAG6_CB(next)->offset < end) {
/* overlap is 'i' bytes */
int i = end - NFCT_FRAG6_CB(next)->offset;
if (i < next->len) {
/* Eat head of the next overlapped fragment
* and leave the loop. The next ones cannot overlap.
*/
DEBUGP("Eat head of the overlapped parts.: %d", i);
if (!pskb_pull(next, i))
goto err;
/* next fragment */
NFCT_FRAG6_CB(next)->offset += i;
fq->meat -= i;
if (next->ip_summed != CHECKSUM_UNNECESSARY)
next->ip_summed = CHECKSUM_NONE;
break;
} else {
struct sk_buff *free_it = next;
/* Old fragmnet is completely overridden with
* new one drop it.
*/
next = next->next;
if (prev)
prev->next = next;
else
fq->fragments = next;
fq->meat -= free_it->len;
frag_kfree_skb(free_it, NULL);
}
}
NFCT_FRAG6_CB(skb)->offset = offset;
/* Insert this fragment in the chain of fragments. */
skb->next = next;
if (prev)
prev->next = skb;
else
fq->fragments = skb;
skb->dev = NULL;
skb_get_timestamp(skb, &fq->stamp);
fq->meat += skb->len;
atomic_add(skb->truesize, &nf_ct_frag6_mem);
/* The first fragment.
* nhoffset is obtained from the first fragment, of course.
*/
if (offset == 0) {
fq->nhoffset = nhoff;
fq->last_in |= FIRST_IN;
}
write_lock(&nf_ct_frag6_lock);
list_move_tail(&fq->lru_list, &nf_ct_frag6_lru_list);
write_unlock(&nf_ct_frag6_lock);
return 0;
err:
return -1;
}
/*
* Check if this packet is complete.
* Returns NULL on failure by any reason, and pointer
* to current nexthdr field in reassembled frame.
*
* It is called with locked fq, and caller must check that
* queue is eligible for reassembly i.e. it is not COMPLETE,
* the last and the first frames arrived and all the bits are here.
*/
static struct sk_buff *
nf_ct_frag6_reasm(struct nf_ct_frag6_queue *fq, struct net_device *dev)
{
struct sk_buff *fp, *op, *head = fq->fragments;
int payload_len;
fq_kill(fq);
BUG_TRAP(head != NULL);
BUG_TRAP(NFCT_FRAG6_CB(head)->offset == 0);
/* Unfragmented part is taken from the first segment. */
payload_len = (head->data - head->nh.raw) - sizeof(struct ipv6hdr) + fq->len - sizeof(struct frag_hdr);
if (payload_len > IPV6_MAXPLEN) {
DEBUGP("payload len is too large.\n");
goto out_oversize;
}
/* Head of list must not be cloned. */
if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) {
DEBUGP("skb is cloned but can't expand head");
goto out_oom;
}
/* If the first fragment is fragmented itself, we split
* it to two chunks: the first with data and paged part
* and the second, holding only fragments. */
if (skb_shinfo(head)->frag_list) {
struct sk_buff *clone;
int i, plen = 0;
if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) {
DEBUGP("Can't alloc skb\n");
goto out_oom;
}
clone->next = head->next;
head->next = clone;
skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
skb_shinfo(head)->frag_list = NULL;
for (i=0; i<skb_shinfo(head)->nr_frags; i++)
plen += skb_shinfo(head)->frags[i].size;
clone->len = clone->data_len = head->data_len - plen;
head->data_len -= clone->len;
head->len -= clone->len;
clone->csum = 0;
clone->ip_summed = head->ip_summed;
NFCT_FRAG6_CB(clone)->orig = NULL;
atomic_add(clone->truesize, &nf_ct_frag6_mem);
}
/* We have to remove fragment header from datagram and to relocate
* header in order to calculate ICV correctly. */
head->nh.raw[fq->nhoffset] = head->h.raw[0];
memmove(head->head + sizeof(struct frag_hdr), head->head,
(head->data - head->head) - sizeof(struct frag_hdr));
head->mac.raw += sizeof(struct frag_hdr);
head->nh.raw += sizeof(struct frag_hdr);
skb_shinfo(head)->frag_list = head->next;
head->h.raw = head->data;
skb_push(head, head->data - head->nh.raw);
atomic_sub(head->truesize, &nf_ct_frag6_mem);
for (fp=head->next; fp; fp = fp->next) {
head->data_len += fp->len;
head->len += fp->len;
if (head->ip_summed != fp->ip_summed)
head->ip_summed = CHECKSUM_NONE;
else if (head->ip_summed == CHECKSUM_HW)
head->csum = csum_add(head->csum, fp->csum);
head->truesize += fp->truesize;
atomic_sub(fp->truesize, &nf_ct_frag6_mem);
}
head->next = NULL;
head->dev = dev;
skb_set_timestamp(head, &fq->stamp);
head->nh.ipv6h->payload_len = htons(payload_len);
/* Yes, and fold redundant checksum back. 8) */
if (head->ip_summed == CHECKSUM_HW)
head->csum = csum_partial(head->nh.raw, head->h.raw-head->nh.raw, head->csum);
fq->fragments = NULL;
/* all original skbs are linked into the NFCT_FRAG6_CB(head).orig */
fp = skb_shinfo(head)->frag_list;
if (NFCT_FRAG6_CB(fp)->orig == NULL)
/* at above code, head skb is divided into two skbs. */
fp = fp->next;
op = NFCT_FRAG6_CB(head)->orig;
for (; fp; fp = fp->next) {
struct sk_buff *orig = NFCT_FRAG6_CB(fp)->orig;
op->next = orig;
op = orig;
NFCT_FRAG6_CB(fp)->orig = NULL;
}
return head;
out_oversize:
if (net_ratelimit())
printk(KERN_DEBUG "nf_ct_frag6_reasm: payload len = %d\n", payload_len);
goto out_fail;
out_oom:
if (net_ratelimit())
printk(KERN_DEBUG "nf_ct_frag6_reasm: no memory for reassembly\n");
out_fail:
return NULL;
}
/*
* find the header just before Fragment Header.
*
* if success return 0 and set ...
* (*prevhdrp): the value of "Next Header Field" in the header
* just before Fragment Header.
* (*prevhoff): the offset of "Next Header Field" in the header
* just before Fragment Header.
* (*fhoff) : the offset of Fragment Header.
*
* Based on ipv6_skip_hdr() in net/ipv6/exthdr.c
*
*/
static int
find_prev_fhdr(struct sk_buff *skb, u8 *prevhdrp, int *prevhoff, int *fhoff)
{
u8 nexthdr = skb->nh.ipv6h->nexthdr;
u8 prev_nhoff = (u8 *)&skb->nh.ipv6h->nexthdr - skb->data;
int start = (u8 *)(skb->nh.ipv6h+1) - skb->data;
int len = skb->len - start;
u8 prevhdr = NEXTHDR_IPV6;
while (nexthdr != NEXTHDR_FRAGMENT) {
struct ipv6_opt_hdr hdr;
int hdrlen;
if (!ipv6_ext_hdr(nexthdr)) {
return -1;
}
if (len < (int)sizeof(struct ipv6_opt_hdr)) {
DEBUGP("too short\n");
return -1;
}
if (nexthdr == NEXTHDR_NONE) {
DEBUGP("next header is none\n");
return -1;
}
if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
BUG();
if (nexthdr == NEXTHDR_AUTH)
hdrlen = (hdr.hdrlen+2)<<2;
else
hdrlen = ipv6_optlen(&hdr);
prevhdr = nexthdr;
prev_nhoff = start;
nexthdr = hdr.nexthdr;
len -= hdrlen;
start += hdrlen;
}
if (len < 0)
return -1;
*prevhdrp = prevhdr;
*prevhoff = prev_nhoff;
*fhoff = start;
return 0;
}
struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb)
{
struct sk_buff *clone;
struct net_device *dev = skb->dev;
struct frag_hdr *fhdr;
struct nf_ct_frag6_queue *fq;
struct ipv6hdr *hdr;
int fhoff, nhoff;
u8 prevhdr;
struct sk_buff *ret_skb = NULL;
/* Jumbo payload inhibits frag. header */
if (skb->nh.ipv6h->payload_len == 0) {
DEBUGP("payload len = 0\n");
return skb;
}
if (find_prev_fhdr(skb, &prevhdr, &nhoff, &fhoff) < 0)
return skb;
clone = skb_clone(skb, GFP_ATOMIC);
if (clone == NULL) {
DEBUGP("Can't clone skb\n");
return skb;
}
NFCT_FRAG6_CB(clone)->orig = skb;
if (!pskb_may_pull(clone, fhoff + sizeof(*fhdr))) {
DEBUGP("message is too short.\n");
goto ret_orig;
}
clone->h.raw = clone->data + fhoff;
hdr = clone->nh.ipv6h;
fhdr = (struct frag_hdr *)clone->h.raw;
if (!(fhdr->frag_off & htons(0xFFF9))) {
DEBUGP("Invalid fragment offset\n");
/* It is not a fragmented frame */
goto ret_orig;
}
if (atomic_read(&nf_ct_frag6_mem) > nf_ct_frag6_high_thresh)
nf_ct_frag6_evictor();
fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr);
if (fq == NULL) {
DEBUGP("Can't find and can't create new queue\n");
goto ret_orig;
}
spin_lock(&fq->lock);
if (nf_ct_frag6_queue(fq, clone, fhdr, nhoff) < 0) {
spin_unlock(&fq->lock);
DEBUGP("Can't insert skb to queue\n");
fq_put(fq, NULL);
goto ret_orig;
}
if (fq->last_in == (FIRST_IN|LAST_IN) && fq->meat == fq->len) {
ret_skb = nf_ct_frag6_reasm(fq, dev);
if (ret_skb == NULL)
DEBUGP("Can't reassemble fragmented packets\n");
}
spin_unlock(&fq->lock);
fq_put(fq, NULL);
return ret_skb;
ret_orig:
kfree_skb(clone);
return skb;
}
void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb,
struct net_device *in, struct net_device *out,
int (*okfn)(struct sk_buff *))
{
struct sk_buff *s, *s2;
for (s = NFCT_FRAG6_CB(skb)->orig; s;) {
nf_conntrack_put_reasm(s->nfct_reasm);
nf_conntrack_get_reasm(skb);
s->nfct_reasm = skb;
s2 = s->next;
NF_HOOK_THRESH(PF_INET6, hooknum, s, in, out, okfn,
NF_IP6_PRI_CONNTRACK_DEFRAG + 1);
s = s2;
}
nf_conntrack_put_reasm(skb);
}
int nf_ct_frag6_kfree_frags(struct sk_buff *skb)
{
struct sk_buff *s, *s2;
for (s = NFCT_FRAG6_CB(skb)->orig; s; s = s2) {
s2 = s->next;
kfree_skb(s);
}
kfree_skb(skb);
return 0;
}
int nf_ct_frag6_init(void)
{
nf_ct_frag6_hash_rnd = (u32) ((num_physpages ^ (num_physpages>>7)) ^
(jiffies ^ (jiffies >> 6)));
init_timer(&nf_ct_frag6_secret_timer);
nf_ct_frag6_secret_timer.function = nf_ct_frag6_secret_rebuild;
nf_ct_frag6_secret_timer.expires = jiffies
+ nf_ct_frag6_secret_interval;
add_timer(&nf_ct_frag6_secret_timer);
return 0;
}
void nf_ct_frag6_cleanup(void)
{
del_timer(&nf_ct_frag6_secret_timer);
nf_ct_frag6_low_thresh = 0;
nf_ct_frag6_evictor();
}
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