- 根目录:
- net
- netfilter
- ipset
- ip_set_hash_gen.h
/* Copyright (C) 2013 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _IP_SET_HASH_GEN_H
#define _IP_SET_HASH_GEN_H
#include <linux/rcupdate.h>
#include <linux/jhash.h>
#include <linux/netfilter/ipset/ip_set_timeout.h>
#ifndef rcu_dereference_bh
#define rcu_dereference_bh(p) rcu_dereference(p)
#endif
#define rcu_dereference_bh_nfnl(p) rcu_dereference_bh_check(p, 1)
/* Hashing which uses arrays to resolve clashing. The hash table is resized
* (doubled) when searching becomes too long.
* Internally jhash is used with the assumption that the size of the
* stored data is a multiple of sizeof(u32). If storage supports timeout,
* the timeout field must be the last one in the data structure - that field
* is ignored when computing the hash key.
*
* Readers and resizing
*
* Resizing can be triggered by userspace command only, and those
* are serialized by the nfnl mutex. During resizing the set is
* read-locked, so the only possible concurrent operations are
* the kernel side readers. Those must be protected by proper RCU locking.
*/
/* Number of elements to store in an initial array block */
#define AHASH_INIT_SIZE 4
/* Max number of elements to store in an array block */
#define AHASH_MAX_SIZE (3*AHASH_INIT_SIZE)
/* Max number of elements can be tuned */
#ifdef IP_SET_HASH_WITH_MULTI
#define AHASH_MAX(h) ((h)->ahash_max)
static inline u8
tune_ahash_max(u8 curr, u32 multi)
{
u32 n;
if (multi < curr)
return curr;
n = curr + AHASH_INIT_SIZE;
/* Currently, at listing one hash bucket must fit into a message.
* Therefore we have a hard limit here.
*/
return n > curr && n <= 64 ? n : curr;
}
#define TUNE_AHASH_MAX(h, multi) \
((h)->ahash_max = tune_ahash_max((h)->ahash_max, multi))
#else
#define AHASH_MAX(h) AHASH_MAX_SIZE
#define TUNE_AHASH_MAX(h, multi)
#endif
/* A hash bucket */
struct hbucket {
void *value; /* the array of the values */
u8 size; /* size of the array */
u8 pos; /* position of the first free entry */
};
/* The hash table: the table size stored here in order to make resizing easy */
struct htable {
u8 htable_bits; /* size of hash table == 2^htable_bits */
struct hbucket bucket[0]; /* hashtable buckets */
};
#define hbucket(h, i) (&((h)->bucket[i]))
#ifndef IPSET_NET_COUNT
#define IPSET_NET_COUNT 1
#endif
/* Book-keeping of the prefixes added to the set */
struct net_prefixes {
u32 nets[IPSET_NET_COUNT]; /* number of elements per cidr */
u8 cidr[IPSET_NET_COUNT]; /* the different cidr values in the set */
};
/* Compute the hash table size */
static size_t
htable_size(u8 hbits)
{
size_t hsize;
/* We must fit both into u32 in jhash and size_t */
if (hbits > 31)
return 0;
hsize = jhash_size(hbits);
if ((((size_t)-1) - sizeof(struct htable))/sizeof(struct hbucket)
< hsize)
return 0;
return hsize * sizeof(struct hbucket) + sizeof(struct htable);
}
/* Compute htable_bits from the user input parameter hashsize */
static u8
htable_bits(u32 hashsize)
{
/* Assume that hashsize == 2^htable_bits */
u8 bits = fls(hashsize - 1);
if (jhash_size(bits) != hashsize)
/* Round up to the first 2^n value */
bits = fls(hashsize);
return bits;
}
static int
hbucket_elem_add(struct hbucket *n, u8 ahash_max, size_t dsize)
{
if (n->pos >= n->size) {
void *tmp;
if (n->size >= ahash_max)
/* Trigger rehashing */
return -EAGAIN;
tmp = kzalloc((n->size + AHASH_INIT_SIZE) * dsize,
GFP_ATOMIC);
if (!tmp)
return -ENOMEM;
if (n->size) {
memcpy(tmp, n->value, n->size * dsize);
kfree(n->value);
}
n->value = tmp;
n->size += AHASH_INIT_SIZE;
}
return 0;
}
#ifdef IP_SET_HASH_WITH_NETS
#if IPSET_NET_COUNT > 1
#define __CIDR(cidr, i) (cidr[i])
#else
#define __CIDR(cidr, i) (cidr)
#endif
#ifdef IP_SET_HASH_WITH_NETS_PACKED
/* When cidr is packed with nomatch, cidr - 1 is stored in the entry */
#define CIDR(cidr, i) (__CIDR(cidr, i) + 1)
#else
#define CIDR(cidr, i) (__CIDR(cidr, i))
#endif
#define SET_HOST_MASK(family) (family == AF_INET ? 32 : 128)
#ifdef IP_SET_HASH_WITH_MULTI
#define NLEN(family) (SET_HOST_MASK(family) + 1)
#else
#define NLEN(family) SET_HOST_MASK(family)
#endif
#else
#define NLEN(family) 0
#endif /* IP_SET_HASH_WITH_NETS */
#endif /* _IP_SET_HASH_GEN_H */
/* Family dependent templates */
#undef ahash_data
#undef mtype_data_equal
#undef mtype_do_data_match
#undef mtype_data_set_flags
#undef mtype_data_reset_flags
#undef mtype_data_netmask
#undef mtype_data_list
#undef mtype_data_next
#undef mtype_elem
#undef mtype_ahash_destroy
#undef mtype_ext_cleanup
#undef mtype_add_cidr
#undef mtype_del_cidr
#undef mtype_ahash_memsize
#undef mtype_flush
#undef mtype_destroy
#undef mtype_gc_init
#undef mtype_same_set
#undef mtype_kadt
#undef mtype_uadt
#undef mtype
#undef mtype_add
#undef mtype_del
#undef mtype_test_cidrs
#undef mtype_test
#undef mtype_expire
#undef mtype_resize
#undef mtype_head
#undef mtype_list
#undef mtype_gc
#undef mtype_gc_init
#undef mtype_variant
#undef mtype_data_match
#undef HKEY
#define mtype_data_equal IPSET_TOKEN(MTYPE, _data_equal)
#ifdef IP_SET_HASH_WITH_NETS
#define mtype_do_data_match IPSET_TOKEN(MTYPE, _do_data_match)
#else
#define mtype_do_data_match(d) 1
#endif
#define mtype_data_set_flags IPSET_TOKEN(MTYPE, _data_set_flags)
#define mtype_data_reset_elem IPSET_TOKEN(MTYPE, _data_reset_elem)
#define mtype_data_reset_flags IPSET_TOKEN(MTYPE, _data_reset_flags)
#define mtype_data_netmask IPSET_TOKEN(MTYPE, _data_netmask)
#define mtype_data_list IPSET_TOKEN(MTYPE, _data_list)
#define mtype_data_next IPSET_TOKEN(MTYPE, _data_next)
#define mtype_elem IPSET_TOKEN(MTYPE, _elem)
#define mtype_ahash_destroy IPSET_TOKEN(MTYPE, _ahash_destroy)
#define mtype_ext_cleanup IPSET_TOKEN(MTYPE, _ext_cleanup)
#define mtype_add_cidr IPSET_TOKEN(MTYPE, _add_cidr)
#define mtype_del_cidr IPSET_TOKEN(MTYPE, _del_cidr)
#define mtype_ahash_memsize IPSET_TOKEN(MTYPE, _ahash_memsize)
#define mtype_flush IPSET_TOKEN(MTYPE, _flush)
#define mtype_destroy IPSET_TOKEN(MTYPE, _destroy)
#define mtype_gc_init IPSET_TOKEN(MTYPE, _gc_init)
#define mtype_same_set IPSET_TOKEN(MTYPE, _same_set)
#define mtype_kadt IPSET_TOKEN(MTYPE, _kadt)
#define mtype_uadt IPSET_TOKEN(MTYPE, _uadt)
#define mtype MTYPE
#define mtype_add IPSET_TOKEN(MTYPE, _add)
#define mtype_del IPSET_TOKEN(MTYPE, _del)
#define mtype_test_cidrs IPSET_TOKEN(MTYPE, _test_cidrs)
#define mtype_test IPSET_TOKEN(MTYPE, _test)
#define mtype_expire IPSET_TOKEN(MTYPE, _expire)
#define mtype_resize IPSET_TOKEN(MTYPE, _resize)
#define mtype_head IPSET_TOKEN(MTYPE, _head)
#define mtype_list IPSET_TOKEN(MTYPE, _list)
#define mtype_gc IPSET_TOKEN(MTYPE, _gc)
#define mtype_variant IPSET_TOKEN(MTYPE, _variant)
#define mtype_data_match IPSET_TOKEN(MTYPE, _data_match)
#ifndef HKEY_DATALEN
#define HKEY_DATALEN sizeof(struct mtype_elem)
#endif
#define HKEY(data, initval, htable_bits) \
(jhash2((u32 *)(data), HKEY_DATALEN/sizeof(u32), initval) \
& jhash_mask(htable_bits))
#ifndef htype
#define htype HTYPE
/* The generic hash structure */
struct htype {
struct htable __rcu *table; /* the hash table */
u32 maxelem; /* max elements in the hash */
u32 elements; /* current element (vs timeout) */
u32 initval; /* random jhash init value */
struct timer_list gc; /* garbage collection when timeout enabled */
struct mtype_elem next; /* temporary storage for uadd */
#ifdef IP_SET_HASH_WITH_MULTI
u8 ahash_max; /* max elements in an array block */
#endif
#ifdef IP_SET_HASH_WITH_NETMASK
u8 netmask; /* netmask value for subnets to store */
#endif
#ifdef IP_SET_HASH_WITH_RBTREE
struct rb_root rbtree;
#endif
#ifdef IP_SET_HASH_WITH_NETS
struct net_prefixes nets[0]; /* book-keeping of prefixes */
#endif
};
#endif
#ifdef IP_SET_HASH_WITH_NETS
/* Network cidr size book keeping when the hash stores different
* sized networks */
static void
mtype_add_cidr(struct htype *h, u8 cidr, u8 nets_length, u8 n)
{
int i, j;
/* Add in increasing prefix order, so larger cidr first */
for (i = 0, j = -1; i < nets_length && h->nets[i].nets[n]; i++) {
if (j != -1)
continue;
else if (h->nets[i].cidr[n] < cidr)
j = i;
else if (h->nets[i].cidr[n] == cidr) {
h->nets[i].nets[n]++;
return;
}
}
if (j != -1) {
for (; i > j; i--) {
h->nets[i].cidr[n] = h->nets[i - 1].cidr[n];
h->nets[i].nets[n] = h->nets[i - 1].nets[n];
}
}
h->nets[i].cidr[n] = cidr;
h->nets[i].nets[n] = 1;
}
static void
mtype_del_cidr(struct htype *h, u8 cidr, u8 nets_length, u8 n)
{
u8 i, j, net_end = nets_length - 1;
for (i = 0; i < nets_length; i++) {
if (h->nets[i].cidr[n] != cidr)
continue;
if (h->nets[i].nets[n] > 1 || i == net_end ||
h->nets[i + 1].nets[n] == 0) {
h->nets[i].nets[n]--;
return;
}
for (j = i; j < net_end && h->nets[j].nets[n]; j++) {
h->nets[j].cidr[n] = h->nets[j + 1].cidr[n];
h->nets[j].nets[n] = h->nets[j + 1].nets[n];
}
h->nets[j].nets[n] = 0;
return;
}
}
#endif
/* Calculate the actual memory size of the set data */
static size_t
mtype_ahash_memsize(const struct htype *h, const struct htable *t,
u8 nets_length, size_t dsize)
{
u32 i;
size_t memsize = sizeof(*h)
+ sizeof(*t)
#ifdef IP_SET_HASH_WITH_NETS
+ sizeof(struct net_prefixes) * nets_length
#endif
+ jhash_size(t->htable_bits) * sizeof(struct hbucket);
for (i = 0; i < jhash_size(t->htable_bits); i++)
memsize += t->bucket[i].size * dsize;
return memsize;
}
/* Get the ith element from the array block n */
#define ahash_data(n, i, dsize) \
((struct mtype_elem *)((n)->value + ((i) * (dsize))))
static void
mtype_ext_cleanup(struct ip_set *set, struct hbucket *n)
{
int i;
for (i = 0; i < n->pos; i++)
ip_set_ext_destroy(set, ahash_data(n, i, set->dsize));
}
/* Flush a hash type of set: destroy all elements */
static void
mtype_flush(struct ip_set *set)
{
struct htype *h = set->data;
struct htable *t;
struct hbucket *n;
u32 i;
t = rcu_dereference_bh_nfnl(h->table);
for (i = 0; i < jhash_size(t->htable_bits); i++) {
n = hbucket(t, i);
if (n->size) {
if (set->extensions & IPSET_EXT_DESTROY)
mtype_ext_cleanup(set, n);
n->size = n->pos = 0;
/* FIXME: use slab cache */
kfree(n->value);
}
}
#ifdef IP_SET_HASH_WITH_NETS
memset(h->nets, 0, sizeof(struct net_prefixes) * NLEN(set->family));
#endif
h->elements = 0;
}
/* Destroy the hashtable part of the set */
static void
mtype_ahash_destroy(struct ip_set *set, struct htable *t, bool ext_destroy)
{
struct hbucket *n;
u32 i;
for (i = 0; i < jhash_size(t->htable_bits); i++) {
n = hbucket(t, i);
if (n->size) {
if (set->extensions & IPSET_EXT_DESTROY && ext_destroy)
mtype_ext_cleanup(set, n);
/* FIXME: use slab cache */
kfree(n->value);
}
}
ip_set_free(t);
}
/* Destroy a hash type of set */
static void
mtype_destroy(struct ip_set *set)
{
struct htype *h = set->data;
if (set->extensions & IPSET_EXT_TIMEOUT)
del_timer_sync(&h->gc);
mtype_ahash_destroy(set, rcu_dereference_bh_nfnl(h->table), true);
#ifdef IP_SET_HASH_WITH_RBTREE
rbtree_destroy(&h->rbtree);
#endif
kfree(h);
set->data = NULL;
}
static void
mtype_gc_init(struct ip_set *set, void (*gc)(unsigned long ul_set))
{
struct htype *h = set->data;
init_timer(&h->gc);
h->gc.data = (unsigned long) set;
h->gc.function = gc;
h->gc.expires = jiffies + IPSET_GC_PERIOD(set->timeout) * HZ;
add_timer(&h->gc);
pr_debug("gc initialized, run in every %u\n",
IPSET_GC_PERIOD(set->timeout));
}
static bool
mtype_same_set(const struct ip_set *a, const struct ip_set *b)
{
const struct htype *x = a->data;
const struct htype *y = b->data;
/* Resizing changes htable_bits, so we ignore it */
return x->maxelem == y->maxelem &&
a->timeout == b->timeout &&
#ifdef IP_SET_HASH_WITH_NETMASK
x->netmask == y->netmask &&
#endif
a->extensions == b->extensions;
}
/* Delete expired elements from the hashtable */
static void
mtype_expire(struct ip_set *set, struct htype *h, u8 nets_length, size_t dsize)
{
struct htable *t;
struct hbucket *n;
struct mtype_elem *data;
u32 i;
int j;
#ifdef IP_SET_HASH_WITH_NETS
u8 k;
#endif
rcu_read_lock_bh();
t = rcu_dereference_bh(h->table);
for (i = 0; i < jhash_size(t->htable_bits); i++) {
n = hbucket(t, i);
for (j = 0; j < n->pos; j++) {
data = ahash_data(n, j, dsize);
if (ip_set_timeout_expired(ext_timeout(data, set))) {
pr_debug("expired %u/%u\n", i, j);
#ifdef IP_SET_HASH_WITH_NETS
for (k = 0; k < IPSET_NET_COUNT; k++)
mtype_del_cidr(h, CIDR(data->cidr, k),
nets_length, k);
#endif
ip_set_ext_destroy(set, data);
if (j != n->pos - 1)
/* Not last one */
memcpy(data,
ahash_data(n, n->pos - 1, dsize),
dsize);
n->pos--;
h->elements--;
}
}
if (n->pos + AHASH_INIT_SIZE < n->size) {
void *tmp = kzalloc((n->size - AHASH_INIT_SIZE)
* dsize,
GFP_ATOMIC);
if (!tmp)
/* Still try to delete expired elements */
continue;
n->size -= AHASH_INIT_SIZE;
memcpy(tmp, n->value, n->size * dsize);
kfree(n->value);
n->value = tmp;
}
}
rcu_read_unlock_bh();
}
static void
mtype_gc(unsigned long ul_set)
{
struct ip_set *set = (struct ip_set *) ul_set;
struct htype *h = set->data;
pr_debug("called\n");
write_lock_bh(&set->lock);
mtype_expire(set, h, NLEN(set->family), set->dsize);
write_unlock_bh(&set->lock);
h->gc.expires = jiffies + IPSET_GC_PERIOD(set->timeout) * HZ;
add_timer(&h->gc);
}
/* Resize a hash: create a new hash table with doubling the hashsize
* and inserting the elements to it. Repeat until we succeed or
* fail due to memory pressures. */
static int
mtype_resize(struct ip_set *set, bool retried)
{
struct htype *h = set->data;
struct htable *t, *orig = rcu_dereference_bh_nfnl(h->table);
u8 htable_bits = orig->htable_bits;
#ifdef IP_SET_HASH_WITH_NETS
u8 flags;
#endif
struct mtype_elem *data;
struct mtype_elem *d;
struct hbucket *n, *m;
u32 i, j;
int ret;
/* Try to cleanup once */
if (SET_WITH_TIMEOUT(set) && !retried) {
i = h->elements;
write_lock_bh(&set->lock);
mtype_expire(set, set->data, NLEN(set->family), set->dsize);
write_unlock_bh(&set->lock);
if (h->elements < i)
return 0;
}
retry:
ret = 0;
htable_bits++;
pr_debug("attempt to resize set %s from %u to %u, t %p\n",
set->name, orig->htable_bits, htable_bits, orig);
if (!htable_bits) {
/* In case we have plenty of memory :-) */
pr_warning("Cannot increase the hashsize of set %s further\n",
set->name);
return -IPSET_ERR_HASH_FULL;
}
t = ip_set_alloc(sizeof(*t)
+ jhash_size(htable_bits) * sizeof(struct hbucket));
if (!t)
return -ENOMEM;
t->htable_bits = htable_bits;
read_lock_bh(&set->lock);
for (i = 0; i < jhash_size(orig->htable_bits); i++) {
n = hbucket(orig, i);
for (j = 0; j < n->pos; j++) {
data = ahash_data(n, j, set->dsize);
#ifdef IP_SET_HASH_WITH_NETS
flags = 0;
mtype_data_reset_flags(data, &flags);
#endif
m = hbucket(t, HKEY(data, h->initval, htable_bits));
ret = hbucket_elem_add(m, AHASH_MAX(h), set->dsize);
if (ret < 0) {
#ifdef IP_SET_HASH_WITH_NETS
mtype_data_reset_flags(data, &flags);
#endif
read_unlock_bh(&set->lock);
mtype_ahash_destroy(set, t, false);
if (ret == -EAGAIN)
goto retry;
return ret;
}
d = ahash_data(m, m->pos++, set->dsize);
memcpy(d, data, set->dsize);
#ifdef IP_SET_HASH_WITH_NETS
mtype_data_reset_flags(d, &flags);
#endif
}
}
rcu_assign_pointer(h->table, t);
read_unlock_bh(&set->lock);
/* Give time to other readers of the set */
synchronize_rcu_bh();
pr_debug("set %s resized from %u (%p) to %u (%p)\n", set->name,
orig->htable_bits, orig, t->htable_bits, t);
mtype_ahash_destroy(set, orig, false);
return 0;
}
/* Add an element to a hash and update the internal counters when succeeded,
* otherwise report the proper error code. */
static int
mtype_add(struct ip_set *set, void *value, const struct ip_set_ext *ext,
struct ip_set_ext *mext, u32 flags)
{
struct htype *h = set->data;
struct htable *t;
const struct mtype_elem *d = value;
struct mtype_elem *data;
struct hbucket *n;
int i, ret = 0;
int j = AHASH_MAX(h) + 1;
bool flag_exist = flags & IPSET_FLAG_EXIST;
u32 key, multi = 0;
if (SET_WITH_TIMEOUT(set) && h->elements >= h->maxelem)
/* FIXME: when set is full, we slow down here */
mtype_expire(set, h, NLEN(set->family), set->dsize);
if (h->elements >= h->maxelem) {
if (net_ratelimit())
pr_warning("Set %s is full, maxelem %u reached\n",
set->name, h->maxelem);
return -IPSET_ERR_HASH_FULL;
}
rcu_read_lock_bh();
t = rcu_dereference_bh(h->table);
key = HKEY(value, h->initval, t->htable_bits);
n = hbucket(t, key);
for (i = 0; i < n->pos; i++) {
data = ahash_data(n, i, set->dsize);
if (mtype_data_equal(data, d, &multi)) {
if (flag_exist ||
(SET_WITH_TIMEOUT(set) &&
ip_set_timeout_expired(ext_timeout(data, set)))) {
/* Just the extensions could be overwritten */
j = i;
goto reuse_slot;
} else {
ret = -IPSET_ERR_EXIST;
goto out;
}
}
/* Reuse first timed out entry */
if (SET_WITH_TIMEOUT(set) &&
ip_set_timeout_expired(ext_timeout(data, set)) &&
j != AHASH_MAX(h) + 1)
j = i;
}
reuse_slot:
if (j != AHASH_MAX(h) + 1) {
/* Fill out reused slot */
data = ahash_data(n, j, set->dsize);
#ifdef IP_SET_HASH_WITH_NETS
for (i = 0; i < IPSET_NET_COUNT; i++) {
mtype_del_cidr(h, CIDR(data->cidr, i),
NLEN(set->family), i);
mtype_add_cidr(h, CIDR(d->cidr, i),
NLEN(set->family), i);
}
#endif
ip_set_ext_destroy(set, data);
} else {
/* Use/create a new slot */
TUNE_AHASH_MAX(h, multi);
ret = hbucket_elem_add(n, AHASH_MAX(h), set->dsize);
if (ret != 0) {
if (ret == -EAGAIN)
mtype_data_next(&h->next, d);
goto out;
}
data = ahash_data(n, n->pos++, set->dsize);
#ifdef IP_SET_HASH_WITH_NETS
for (i = 0; i < IPSET_NET_COUNT; i++)
mtype_add_cidr(h, CIDR(d->cidr, i), NLEN(set->family),
i);
#endif
h->elements++;
}
memcpy(data, d, sizeof(struct mtype_elem));
#ifdef IP_SET_HASH_WITH_NETS
mtype_data_set_flags(data, flags);
#endif
if (SET_WITH_TIMEOUT(set))
ip_set_timeout_set(ext_timeout(data, set), ext->timeout);
if (SET_WITH_COUNTER(set))
ip_set_init_counter(ext_counter(data, set), ext);
if (SET_WITH_COMMENT(set))
ip_set_init_comment(ext_comment(data, set), ext);
out:
rcu_read_unlock_bh();
return ret;
}
/* Delete an element from the hash: swap it with the last element
* and free up space if possible.
*/
static int
mtype_del(struct ip_set *set, void *value, const struct ip_set_ext *ext,
struct ip_set_ext *mext, u32 flags)
{
struct htype *h = set->data;
struct htable *t;
const struct mtype_elem *d = value;
struct mtype_elem *data;
struct hbucket *n;
int i, ret = -IPSET_ERR_EXIST;
#ifdef IP_SET_HASH_WITH_NETS
u8 j;
#endif
u32 key, multi = 0;
rcu_read_lock_bh();
t = rcu_dereference_bh(h->table);
key = HKEY(value, h->initval, t->htable_bits);
n = hbucket(t, key);
for (i = 0; i < n->pos; i++) {
data = ahash_data(n, i, set->dsize);
if (!mtype_data_equal(data, d, &multi))
continue;
if (SET_WITH_TIMEOUT(set) &&
ip_set_timeout_expired(ext_timeout(data, set)))
goto out;
if (i != n->pos - 1)
/* Not last one */
memcpy(data, ahash_data(n, n->pos - 1, set->dsize),
set->dsize);
n->pos--;
h->elements--;
#ifdef IP_SET_HASH_WITH_NETS
for (j = 0; j < IPSET_NET_COUNT; j++)
mtype_del_cidr(h, CIDR(d->cidr, j), NLEN(set->family),
j);
#endif
ip_set_ext_destroy(set, data);
if (n->pos + AHASH_INIT_SIZE < n->size) {
void *tmp = kzalloc((n->size - AHASH_INIT_SIZE)
* set->dsize,
GFP_ATOMIC);
if (!tmp) {
ret = 0;
goto out;
}
n->size -= AHASH_INIT_SIZE;
memcpy(tmp, n->value, n->size * set->dsize);
kfree(n->value);
n->value = tmp;
}
ret = 0;
goto out;
}
out:
rcu_read_unlock_bh();
return ret;
}
static inline int
mtype_data_match(struct mtype_elem *data, const struct ip_set_ext *ext,
struct ip_set_ext *mext, struct ip_set *set, u32 flags)
{
if (SET_WITH_COUNTER(set))
ip_set_update_counter(ext_counter(data, set),
ext, mext, flags);
return mtype_do_data_match(data);
}
#ifdef IP_SET_HASH_WITH_NETS
/* Special test function which takes into account the different network
* sizes added to the set */
static int
mtype_test_cidrs(struct ip_set *set, struct mtype_elem *d,
const struct ip_set_ext *ext,
struct ip_set_ext *mext, u32 flags)
{
struct htype *h = set->data;
struct htable *t = rcu_dereference_bh(h->table);
struct hbucket *n;
struct mtype_elem *data;
#if IPSET_NET_COUNT == 2
struct mtype_elem orig = *d;
int i, j = 0, k;
#else
int i, j = 0;
#endif
u32 key, multi = 0;
u8 nets_length = NLEN(set->family);
pr_debug("test by nets\n");
for (; j < nets_length && h->nets[j].nets[0] && !multi; j++) {
#if IPSET_NET_COUNT == 2
mtype_data_reset_elem(d, &orig);
mtype_data_netmask(d, h->nets[j].cidr[0], false);
for (k = 0; k < nets_length && h->nets[k].nets[1] && !multi;
k++) {
mtype_data_netmask(d, h->nets[k].cidr[1], true);
#else
mtype_data_netmask(d, h->nets[j].cidr[0]);
#endif
key = HKEY(d, h->initval, t->htable_bits);
n = hbucket(t, key);
for (i = 0; i < n->pos; i++) {
data = ahash_data(n, i, set->dsize);
if (!mtype_data_equal(data, d, &multi))
continue;
if (SET_WITH_TIMEOUT(set)) {
if (!ip_set_timeout_expired(
ext_timeout(data, set)))
return mtype_data_match(data, ext,
mext, set,
flags);
#ifdef IP_SET_HASH_WITH_MULTI
multi = 0;
#endif
} else
return mtype_data_match(data, ext,
mext, set, flags);
}
#if IPSET_NET_COUNT == 2
}
#endif
}
return 0;
}
#endif
/* Test whether the element is added to the set */
static int
mtype_test(struct ip_set *set, void *value, const struct ip_set_ext *ext,
struct ip_set_ext *mext, u32 flags)
{
struct htype *h = set->data;
struct htable *t;
struct mtype_elem *d = value;
struct hbucket *n;
struct mtype_elem *data;
int i, ret = 0;
u32 key, multi = 0;
rcu_read_lock_bh();
t = rcu_dereference_bh(h->table);
#ifdef IP_SET_HASH_WITH_NETS
/* If we test an IP address and not a network address,
* try all possible network sizes */
for (i = 0; i < IPSET_NET_COUNT; i++)
if (CIDR(d->cidr, i) != SET_HOST_MASK(set->family))
break;
if (i == IPSET_NET_COUNT) {
ret = mtype_test_cidrs(set, d, ext, mext, flags);
goto out;
}
#endif
key = HKEY(d, h->initval, t->htable_bits);
n = hbucket(t, key);
for (i = 0; i < n->pos; i++) {
data = ahash_data(n, i, set->dsize);
if (mtype_data_equal(data, d, &multi) &&
!(SET_WITH_TIMEOUT(set) &&
ip_set_timeout_expired(ext_timeout(data, set)))) {
ret = mtype_data_match(data, ext, mext, set, flags);
goto out;
}
}
out:
rcu_read_unlock_bh();
return ret;
}
/* Reply a HEADER request: fill out the header part of the set */
static int
mtype_head(struct ip_set *set, struct sk_buff *skb)
{
const struct htype *h = set->data;
const struct htable *t;
struct nlattr *nested;
size_t memsize;
t = rcu_dereference_bh_nfnl(h->table);
memsize = mtype_ahash_memsize(h, t, NLEN(set->family), set->dsize);
nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
if (!nested)
goto nla_put_failure;
if (nla_put_net32(skb, IPSET_ATTR_HASHSIZE,
htonl(jhash_size(t->htable_bits))) ||
nla_put_net32(skb, IPSET_ATTR_MAXELEM, htonl(h->maxelem)))
goto nla_put_failure;
#ifdef IP_SET_HASH_WITH_NETMASK
if (h->netmask != HOST_MASK &&
nla_put_u8(skb, IPSET_ATTR_NETMASK, h->netmask))
goto nla_put_failure;
#endif
if (nla_put_net32(skb, IPSET_ATTR_REFERENCES, htonl(set->ref - 1)) ||
nla_put_net32(skb, IPSET_ATTR_MEMSIZE, htonl(memsize)))
goto nla_put_failure;
if (unlikely(ip_set_put_flags(skb, set)))
goto nla_put_failure;
ipset_nest_end(skb, nested);
return 0;
nla_put_failure:
return -EMSGSIZE;
}
/* Reply a LIST/SAVE request: dump the elements of the specified set */
static int
mtype_list(const struct ip_set *set,
struct sk_buff *skb, struct netlink_callback *cb)
{
const struct htype *h = set->data;
const struct htable *t = rcu_dereference_bh_nfnl(h->table);
struct nlattr *atd, *nested;
const struct hbucket *n;
const struct mtype_elem *e;
u32 first = cb->args[IPSET_CB_ARG0];
/* We assume that one hash bucket fills into one page */
void *incomplete;
int i;
atd = ipset_nest_start(skb, IPSET_ATTR_ADT);
if (!atd)
return -EMSGSIZE;
pr_debug("list hash set %s\n", set->name);
for (; cb->args[IPSET_CB_ARG0] < jhash_size(t->htable_bits);
cb->args[IPSET_CB_ARG0]++) {
incomplete = skb_tail_pointer(skb);
n = hbucket(t, cb->args[IPSET_CB_ARG0]);
pr_debug("cb->arg bucket: %lu, t %p n %p\n",
cb->args[IPSET_CB_ARG0], t, n);
for (i = 0; i < n->pos; i++) {
e = ahash_data(n, i, set->dsize);
if (SET_WITH_TIMEOUT(set) &&
ip_set_timeout_expired(ext_timeout(e, set)))
continue;
pr_debug("list hash %lu hbucket %p i %u, data %p\n",
cb->args[IPSET_CB_ARG0], n, i, e);
nested = ipset_nest_start(skb, IPSET_ATTR_DATA);
if (!nested) {
if (cb->args[IPSET_CB_ARG0] == first) {
nla_nest_cancel(skb, atd);
return -EMSGSIZE;
} else
goto nla_put_failure;
}
if (mtype_data_list(skb, e))
goto nla_put_failure;
if (ip_set_put_extensions(skb, set, e, true))
goto nla_put_failure;
ipset_nest_end(skb, nested);
}
}
ipset_nest_end(skb, atd);
/* Set listing finished */
cb->args[IPSET_CB_ARG0] = 0;
return 0;
nla_put_failure:
nlmsg_trim(skb, incomplete);
if (unlikely(first == cb->args[IPSET_CB_ARG0])) {
pr_warning("Can't list set %s: one bucket does not fit into "
"a message. Please report it!\n", set->name);
cb->args[IPSET_CB_ARG0] = 0;
return -EMSGSIZE;
}
ipset_nest_end(skb, atd);
return 0;
}
static int
IPSET_TOKEN(MTYPE, _kadt)(struct ip_set *set, const struct sk_buff *skb,
const struct xt_action_param *par,
enum ipset_adt adt, struct ip_set_adt_opt *opt);
static int
IPSET_TOKEN(MTYPE, _uadt)(struct ip_set *set, struct nlattr *tb[],
enum ipset_adt adt, u32 *lineno, u32 flags, bool retried);
static const struct ip_set_type_variant mtype_variant = {
.kadt = mtype_kadt,
.uadt = mtype_uadt,
.adt = {
[IPSET_ADD] = mtype_add,
[IPSET_DEL] = mtype_del,
[IPSET_TEST] = mtype_test,
},
.destroy = mtype_destroy,
.flush = mtype_flush,
.head = mtype_head,
.list = mtype_list,
.resize = mtype_resize,
.same_set = mtype_same_set,
};
#ifdef IP_SET_EMIT_CREATE
static int
IPSET_TOKEN(HTYPE, _create)(struct net *net, struct ip_set *set,
struct nlattr *tb[], u32 flags)
{
u32 hashsize = IPSET_DEFAULT_HASHSIZE, maxelem = IPSET_DEFAULT_MAXELEM;
u8 hbits;
#ifdef IP_SET_HASH_WITH_NETMASK
u8 netmask;
#endif
size_t hsize;
struct HTYPE *h;
struct htable *t;
if (!(set->family == NFPROTO_IPV4 || set->family == NFPROTO_IPV6))
return -IPSET_ERR_INVALID_FAMILY;
#ifdef IP_SET_HASH_WITH_NETMASK
netmask = set->family == NFPROTO_IPV4 ? 32 : 128;
pr_debug("Create set %s with family %s\n",
set->name, set->family == NFPROTO_IPV4 ? "inet" : "inet6");
#endif
if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_HASHSIZE) ||
!ip_set_optattr_netorder(tb, IPSET_ATTR_MAXELEM) ||
!ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
!ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
return -IPSET_ERR_PROTOCOL;
if (tb[IPSET_ATTR_HASHSIZE]) {
hashsize = ip_set_get_h32(tb[IPSET_ATTR_HASHSIZE]);
if (hashsize < IPSET_MIMINAL_HASHSIZE)
hashsize = IPSET_MIMINAL_HASHSIZE;
}
if (tb[IPSET_ATTR_MAXELEM])
maxelem = ip_set_get_h32(tb[IPSET_ATTR_MAXELEM]);
#ifdef IP_SET_HASH_WITH_NETMASK
if (tb[IPSET_ATTR_NETMASK]) {
netmask = nla_get_u8(tb[IPSET_ATTR_NETMASK]);
if ((set->family == NFPROTO_IPV4 && netmask > 32) ||
(set->family == NFPROTO_IPV6 && netmask > 128) ||
netmask == 0)
return -IPSET_ERR_INVALID_NETMASK;
}
#endif
hsize = sizeof(*h);
#ifdef IP_SET_HASH_WITH_NETS
hsize += sizeof(struct net_prefixes) *
(set->family == NFPROTO_IPV4 ? 32 : 128);
#endif
h = kzalloc(hsize, GFP_KERNEL);
if (!h)
return -ENOMEM;
h->maxelem = maxelem;
#ifdef IP_SET_HASH_WITH_NETMASK
h->netmask = netmask;
#endif
get_random_bytes(&h->initval, sizeof(h->initval));
set->timeout = IPSET_NO_TIMEOUT;
hbits = htable_bits(hashsize);
hsize = htable_size(hbits);
if (hsize == 0) {
kfree(h);
return -ENOMEM;
}
t = ip_set_alloc(hsize);
if (!t) {
kfree(h);
return -ENOMEM;
}
t->htable_bits = hbits;
rcu_assign_pointer(h->table, t);
set->data = h;
if (set->family == NFPROTO_IPV4) {
set->variant = &IPSET_TOKEN(HTYPE, 4_variant);
set->dsize = ip_set_elem_len(set, tb,
sizeof(struct IPSET_TOKEN(HTYPE, 4_elem)));
} else {
set->variant = &IPSET_TOKEN(HTYPE, 6_variant);
set->dsize = ip_set_elem_len(set, tb,
sizeof(struct IPSET_TOKEN(HTYPE, 6_elem)));
}
if (tb[IPSET_ATTR_TIMEOUT]) {
set->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
if (set->family == NFPROTO_IPV4)
IPSET_TOKEN(HTYPE, 4_gc_init)(set,
IPSET_TOKEN(HTYPE, 4_gc));
else
IPSET_TOKEN(HTYPE, 6_gc_init)(set,
IPSET_TOKEN(HTYPE, 6_gc));
}
pr_debug("create %s hashsize %u (%u) maxelem %u: %p(%p)\n",
set->name, jhash_size(t->htable_bits),
t->htable_bits, h->maxelem, set->data, t);
return 0;
}
#endif /* IP_SET_EMIT_CREATE */