blob: 2c9609929c7167e86c02dfab5d0bc8a9a78ab8b0 [file] [log] [blame]
/* 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/types.h>
#include <linux/netfilter/ipset/ip_set_timeout.h>
#define __ipset_dereference_protected(p, c) rcu_dereference_protected(p, c)
#define ipset_dereference_protected(p, set) \
__ipset_dereference_protected(p, lockdep_is_held(&(set)->lock))
#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).
*
* 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 muber of elements in the array block when tuned */
#define AHASH_MAX_TUNED 64
/* 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 <= AHASH_MAX_TUNED ? 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 {
struct rcu_head rcu; /* for call_rcu */
/* Which positions are used in the array */
DECLARE_BITMAP(used, AHASH_MAX_TUNED);
u8 size; /* size of the array */
u8 pos; /* position of the first free entry */
unsigned char value[0] /* the array of the values */
__aligned(__alignof__(u64));
};
/* The hash table: the table size stored here in order to make resizing easy */
struct htable {
atomic_t ref; /* References for resizing */
atomic_t uref; /* References for dumping */
u8 htable_bits; /* size of hash table == 2^htable_bits */
struct hbucket __rcu *bucket[0]; /* hashtable buckets */
};
#define hbucket(h, i) ((h)->bucket[i])
#define ext_size(n, dsize) \
(sizeof(struct hbucket) + (n) * (dsize))
#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 for this cidr */
u8 cidr[IPSET_NET_COUNT]; /* the cidr value */
};
/* 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;
}
#ifdef IP_SET_HASH_WITH_NETS
#if IPSET_NET_COUNT > 1
#define __CIDR(cidr, i) (cidr[i])
#else
#define __CIDR(cidr, i) (cidr)
#endif
/* cidr + 1 is stored in net_prefixes to support /0 */
#define NCIDR_PUT(cidr) ((cidr) + 1)
#define NCIDR_GET(cidr) ((cidr) - 1)
#ifdef IP_SET_HASH_WITH_NETS_PACKED
/* When cidr is packed with nomatch, cidr - 1 is stored in the data entry */
#define DCIDR_PUT(cidr) ((cidr) - 1)
#define DCIDR_GET(cidr, i) (__CIDR(cidr, i) + 1)
#else
#define DCIDR_PUT(cidr) (cidr)
#define DCIDR_GET(cidr, i) __CIDR(cidr, i)
#endif
#define INIT_CIDR(cidr, host_mask) \
DCIDR_PUT(((cidr) ? NCIDR_GET(cidr) : host_mask))
#ifdef IP_SET_HASH_WITH_NET0
/* cidr from 0 to HOST_MASK value and c = cidr + 1 */
#define NLEN (HOST_MASK + 1)
#define CIDR_POS(c) ((c) - 1)
#else
/* cidr from 1 to HOST_MASK value and c = cidr + 1 */
#define NLEN HOST_MASK
#define CIDR_POS(c) ((c) - 2)
#endif
#else
#define NLEN 0
#endif /* IP_SET_HASH_WITH_NETS */
#endif /* _IP_SET_HASH_GEN_H */
#ifndef MTYPE
#error "MTYPE is not defined!"
#endif
#ifndef HTYPE
#error "HTYPE is not defined!"
#endif
#ifndef HOST_MASK
#error "HOST_MASK is not defined!"
#endif
/* Family dependent templates */
#undef ahash_data
#undef mtype_data_equal
#undef mtype_do_data_match
#undef mtype_data_set_flags
#undef mtype_data_reset_elem
#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_same_set
#undef mtype_kadt
#undef mtype_uadt
#undef mtype_add
#undef mtype_del
#undef mtype_test_cidrs
#undef mtype_test
#undef mtype_uref
#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 htype
#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_same_set IPSET_TOKEN(MTYPE, _same_set)
#define mtype_kadt IPSET_TOKEN(MTYPE, _kadt)
#define mtype_uadt IPSET_TOKEN(MTYPE, _uadt)
#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_uref IPSET_TOKEN(MTYPE, _uref)
#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_gc_init IPSET_TOKEN(MTYPE, _gc_init)
#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 htype MTYPE
#define HKEY(data, initval, htable_bits) \
({ \
const u32 *__k = (const u32 *)data; \
u32 __l = HKEY_DATALEN / sizeof(u32); \
\
BUILD_BUG_ON(HKEY_DATALEN % sizeof(u32) != 0); \
\
jhash2(__k, __l, initval) & jhash_mask(htable_bits); \
})
/* The generic hash structure */
struct htype {
struct htable __rcu *table; /* the hash table */
struct timer_list gc; /* garbage collection when timeout enabled */
struct ip_set *set; /* attached to this ip_set */
u32 maxelem; /* max elements in the hash */
u32 initval; /* random jhash init value */
#ifdef IP_SET_HASH_WITH_MARKMASK
u32 markmask; /* markmask value for mark mask to store */
#endif
#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
struct mtype_elem next; /* temporary storage for uadd */
#ifdef IP_SET_HASH_WITH_NETS
struct net_prefixes nets[NLEN]; /* book-keeping of prefixes */
#endif
};
#ifdef IP_SET_HASH_WITH_NETS
/* Network cidr size book keeping when the hash stores different
* sized networks. cidr == real cidr + 1 to support /0.
*/
static void
mtype_add_cidr(struct htype *h, u8 cidr, u8 n)
{
int i, j;
/* Add in increasing prefix order, so larger cidr first */
for (i = 0, j = -1; i < NLEN && h->nets[i].cidr[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[CIDR_POS(cidr)].nets[n]++;
return;
}
}
if (j != -1) {
for (; i > j; i--)
h->nets[i].cidr[n] = h->nets[i - 1].cidr[n];
}
h->nets[i].cidr[n] = cidr;
h->nets[CIDR_POS(cidr)].nets[n] = 1;
}
static void
mtype_del_cidr(struct htype *h, u8 cidr, u8 n)
{
u8 i, j, net_end = NLEN - 1;
for (i = 0; i < NLEN; i++) {
if (h->nets[i].cidr[n] != cidr)
continue;
h->nets[CIDR_POS(cidr)].nets[n]--;
if (h->nets[CIDR_POS(cidr)].nets[n] > 0)
return;
for (j = i; j < net_end && h->nets[j].cidr[n]; j++)
h->nets[j].cidr[n] = h->nets[j + 1].cidr[n];
h->nets[j].cidr[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)
{
return sizeof(*h) + sizeof(*t);
}
/* 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++)
if (test_bit(i, n->used))
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 = ipset_dereference_protected(h->table, set);
for (i = 0; i < jhash_size(t->htable_bits); i++) {
n = __ipset_dereference_protected(hbucket(t, i), 1);
if (!n)
continue;
if (set->extensions & IPSET_EXT_DESTROY)
mtype_ext_cleanup(set, n);
/* FIXME: use slab cache */
rcu_assign_pointer(hbucket(t, i), NULL);
kfree_rcu(n, rcu);
}
#ifdef IP_SET_HASH_WITH_NETS
memset(h->nets, 0, sizeof(h->nets));
#endif
set->elements = 0;
set->ext_size = 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 = __ipset_dereference_protected(hbucket(t, i), 1);
if (!n)
continue;
if (set->extensions & IPSET_EXT_DESTROY && ext_destroy)
mtype_ext_cleanup(set, n);
/* FIXME: use slab cache */
kfree(n);
}
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_WITH_TIMEOUT(set))
del_timer_sync(&h->gc);
mtype_ahash_destroy(set,
__ipset_dereference_protected(h->table, 1), true);
kfree(h);
set->data = NULL;
}
static void
mtype_gc_init(struct ip_set *set, void (*gc)(struct timer_list *t))
{
struct htype *h = set->data;
timer_setup(&h->gc, gc, 0);
mod_timer(&h->gc, jiffies + IPSET_GC_PERIOD(set->timeout) * HZ);
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
#ifdef IP_SET_HASH_WITH_MARKMASK
x->markmask == y->markmask &&
#endif
a->extensions == b->extensions;
}
/* Delete expired elements from the hashtable */
static void
mtype_expire(struct ip_set *set, struct htype *h)
{
struct htable *t;
struct hbucket *n, *tmp;
struct mtype_elem *data;
u32 i, j, d;
size_t dsize = set->dsize;
#ifdef IP_SET_HASH_WITH_NETS
u8 k;
#endif
t = ipset_dereference_protected(h->table, set);
for (i = 0; i < jhash_size(t->htable_bits); i++) {
n = __ipset_dereference_protected(hbucket(t, i), 1);
if (!n)
continue;
for (j = 0, d = 0; j < n->pos; j++) {
if (!test_bit(j, n->used)) {
d++;
continue;
}
data = ahash_data(n, j, dsize);
if (!ip_set_timeout_expired(ext_timeout(data, set)))
continue;
pr_debug("expired %u/%u\n", i, j);
clear_bit(j, n->used);
smp_mb__after_atomic();
#ifdef IP_SET_HASH_WITH_NETS
for (k = 0; k < IPSET_NET_COUNT; k++)
mtype_del_cidr(h,
NCIDR_PUT(DCIDR_GET(data->cidr, k)),
k);
#endif
ip_set_ext_destroy(set, data);
set->elements--;
d++;
}
if (d >= AHASH_INIT_SIZE) {
if (d >= n->size) {
rcu_assign_pointer(hbucket(t, i), NULL);
kfree_rcu(n, rcu);
continue;
}
tmp = kzalloc(sizeof(*tmp) +
(n->size - AHASH_INIT_SIZE) * dsize,
GFP_ATOMIC);
if (!tmp)
/* Still try to delete expired elements */
continue;
tmp->size = n->size - AHASH_INIT_SIZE;
for (j = 0, d = 0; j < n->pos; j++) {
if (!test_bit(j, n->used))
continue;
data = ahash_data(n, j, dsize);
memcpy(tmp->value + d * dsize, data, dsize);
set_bit(d, tmp->used);
d++;
}
tmp->pos = d;
set->ext_size -= ext_size(AHASH_INIT_SIZE, dsize);
rcu_assign_pointer(hbucket(t, i), tmp);
kfree_rcu(n, rcu);
}
}
}
static void
mtype_gc(struct timer_list *t)
{
struct htype *h = from_timer(h, t, gc);
struct ip_set *set = h->set;
pr_debug("called\n");
spin_lock_bh(&set->lock);
mtype_expire(set, h);
spin_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;
u8 htable_bits;
size_t extsize, dsize = set->dsize;
#ifdef IP_SET_HASH_WITH_NETS
u8 flags;
struct mtype_elem *tmp;
#endif
struct mtype_elem *data;
struct mtype_elem *d;
struct hbucket *n, *m;
u32 i, j, key;
int ret;
#ifdef IP_SET_HASH_WITH_NETS
tmp = kmalloc(dsize, GFP_KERNEL);
if (!tmp)
return -ENOMEM;
#endif
rcu_read_lock_bh();
orig = rcu_dereference_bh_nfnl(h->table);
htable_bits = orig->htable_bits;
rcu_read_unlock_bh();
retry:
ret = 0;
htable_bits++;
if (!htable_bits) {
/* In case we have plenty of memory :-) */
pr_warn("Cannot increase the hashsize of set %s further\n",
set->name);
ret = -IPSET_ERR_HASH_FULL;
goto out;
}
t = ip_set_alloc(htable_size(htable_bits));
if (!t) {
ret = -ENOMEM;
goto out;
}
t->htable_bits = htable_bits;
spin_lock_bh(&set->lock);
orig = __ipset_dereference_protected(h->table, 1);
/* There can't be another parallel resizing, but dumping is possible */
atomic_set(&orig->ref, 1);
atomic_inc(&orig->uref);
extsize = 0;
pr_debug("attempt to resize set %s from %u to %u, t %p\n",
set->name, orig->htable_bits, htable_bits, orig);
for (i = 0; i < jhash_size(orig->htable_bits); i++) {
n = __ipset_dereference_protected(hbucket(orig, i), 1);
if (!n)
continue;
for (j = 0; j < n->pos; j++) {
if (!test_bit(j, n->used))
continue;
data = ahash_data(n, j, dsize);
#ifdef IP_SET_HASH_WITH_NETS
/* We have readers running parallel with us,
* so the live data cannot be modified.
*/
flags = 0;
memcpy(tmp, data, dsize);
data = tmp;
mtype_data_reset_flags(data, &flags);
#endif
key = HKEY(data, h->initval, htable_bits);
m = __ipset_dereference_protected(hbucket(t, key), 1);
if (!m) {
m = kzalloc(sizeof(*m) +
AHASH_INIT_SIZE * dsize,
GFP_ATOMIC);
if (!m) {
ret = -ENOMEM;
goto cleanup;
}
m->size = AHASH_INIT_SIZE;
extsize = ext_size(AHASH_INIT_SIZE, dsize);
RCU_INIT_POINTER(hbucket(t, key), m);
} else if (m->pos >= m->size) {
struct hbucket *ht;
if (m->size >= AHASH_MAX(h)) {
ret = -EAGAIN;
} else {
ht = kzalloc(sizeof(*ht) +
(m->size + AHASH_INIT_SIZE)
* dsize,
GFP_ATOMIC);
if (!ht)
ret = -ENOMEM;
}
if (ret < 0)
goto cleanup;
memcpy(ht, m, sizeof(struct hbucket) +
m->size * dsize);
ht->size = m->size + AHASH_INIT_SIZE;
extsize += ext_size(AHASH_INIT_SIZE, dsize);
kfree(m);
m = ht;
RCU_INIT_POINTER(hbucket(t, key), ht);
}
d = ahash_data(m, m->pos, dsize);
memcpy(d, data, dsize);
set_bit(m->pos++, m->used);
#ifdef IP_SET_HASH_WITH_NETS
mtype_data_reset_flags(d, &flags);
#endif
}
}
rcu_assign_pointer(h->table, t);
set->ext_size = extsize;
spin_unlock_bh(&set->lock);
/* Give time to other readers of the set */
synchronize_rcu();
pr_debug("set %s resized from %u (%p) to %u (%p)\n", set->name,
orig->htable_bits, orig, t->htable_bits, t);
/* If there's nobody else dumping the table, destroy it */
if (atomic_dec_and_test(&orig->uref)) {
pr_debug("Table destroy by resize %p\n", orig);
mtype_ahash_destroy(set, orig, false);
}
out:
#ifdef IP_SET_HASH_WITH_NETS
kfree(tmp);
#endif
return ret;
cleanup:
atomic_set(&orig->ref, 0);
atomic_dec(&orig->uref);
spin_unlock_bh(&set->lock);
mtype_ahash_destroy(set, t, false);
if (ret == -EAGAIN)
goto retry;
goto out;
}
/* 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, *old = ERR_PTR(-ENOENT);
int i, j = -1;
bool flag_exist = flags & IPSET_FLAG_EXIST;
bool deleted = false, forceadd = false, reuse = false;
u32 key, multi = 0;
if (set->elements >= h->maxelem) {
if (SET_WITH_TIMEOUT(set))
/* FIXME: when set is full, we slow down here */
mtype_expire(set, h);
if (set->elements >= h->maxelem && SET_WITH_FORCEADD(set))
forceadd = true;
}
t = ipset_dereference_protected(h->table, set);
key = HKEY(value, h->initval, t->htable_bits);
n = __ipset_dereference_protected(hbucket(t, key), 1);
if (!n) {
if (forceadd || set->elements >= h->maxelem)
goto set_full;
old = NULL;
n = kzalloc(sizeof(*n) + AHASH_INIT_SIZE * set->dsize,
GFP_ATOMIC);
if (!n)
return -ENOMEM;
n->size = AHASH_INIT_SIZE;
set->ext_size += ext_size(AHASH_INIT_SIZE, set->dsize);
goto copy_elem;
}
for (i = 0; i < n->pos; i++) {
if (!test_bit(i, n->used)) {
/* Reuse first deleted entry */
if (j == -1) {
deleted = reuse = true;
j = i;
}
continue;
}
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 overwrite_extensions;
}
return -IPSET_ERR_EXIST;
}
/* Reuse first timed out entry */
if (SET_WITH_TIMEOUT(set) &&
ip_set_timeout_expired(ext_timeout(data, set)) &&
j == -1) {
j = i;
reuse = true;
}
}
if (reuse || forceadd) {
data = ahash_data(n, j, set->dsize);
if (!deleted) {
#ifdef IP_SET_HASH_WITH_NETS
for (i = 0; i < IPSET_NET_COUNT; i++)
mtype_del_cidr(h,
NCIDR_PUT(DCIDR_GET(data->cidr, i)),
i);
#endif
ip_set_ext_destroy(set, data);
set->elements--;
}
goto copy_data;
}
if (set->elements >= h->maxelem)
goto set_full;
/* Create a new slot */
if (n->pos >= n->size) {
TUNE_AHASH_MAX(h, multi);
if (n->size >= AHASH_MAX(h)) {
/* Trigger rehashing */
mtype_data_next(&h->next, d);
return -EAGAIN;
}
old = n;
n = kzalloc(sizeof(*n) +
(old->size + AHASH_INIT_SIZE) * set->dsize,
GFP_ATOMIC);
if (!n)
return -ENOMEM;
memcpy(n, old, sizeof(struct hbucket) +
old->size * set->dsize);
n->size = old->size + AHASH_INIT_SIZE;
set->ext_size += ext_size(AHASH_INIT_SIZE, set->dsize);
}
copy_elem:
j = n->pos++;
data = ahash_data(n, j, set->dsize);
copy_data:
set->elements++;
#ifdef IP_SET_HASH_WITH_NETS
for (i = 0; i < IPSET_NET_COUNT; i++)
mtype_add_cidr(h, NCIDR_PUT(DCIDR_GET(d->cidr, i)), i);
#endif
memcpy(data, d, sizeof(struct mtype_elem));
overwrite_extensions:
#ifdef IP_SET_HASH_WITH_NETS
mtype_data_set_flags(data, flags);
#endif
if (SET_WITH_COUNTER(set))
ip_set_init_counter(ext_counter(data, set), ext);
if (SET_WITH_COMMENT(set))
ip_set_init_comment(set, ext_comment(data, set), ext);
if (SET_WITH_SKBINFO(set))
ip_set_init_skbinfo(ext_skbinfo(data, set), ext);
/* Must come last for the case when timed out entry is reused */
if (SET_WITH_TIMEOUT(set))
ip_set_timeout_set(ext_timeout(data, set), ext->timeout);
smp_mb__before_atomic();
set_bit(j, n->used);
if (old != ERR_PTR(-ENOENT)) {
rcu_assign_pointer(hbucket(t, key), n);
if (old)
kfree_rcu(old, rcu);
}
return 0;
set_full:
if (net_ratelimit())
pr_warn("Set %s is full, maxelem %u reached\n",
set->name, h->maxelem);
return -IPSET_ERR_HASH_FULL;
}
/* Delete an element from the hash 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, j, k, ret = -IPSET_ERR_EXIST;
u32 key, multi = 0;
size_t dsize = set->dsize;
t = ipset_dereference_protected(h->table, set);
key = HKEY(value, h->initval, t->htable_bits);
n = __ipset_dereference_protected(hbucket(t, key), 1);
if (!n)
goto out;
for (i = 0, k = 0; i < n->pos; i++) {
if (!test_bit(i, n->used)) {
k++;
continue;
}
data = ahash_data(n, i, dsize);
if (!mtype_data_equal(data, d, &multi))
continue;
if (SET_WITH_TIMEOUT(set) &&
ip_set_timeout_expired(ext_timeout(data, set)))
goto out;
ret = 0;
clear_bit(i, n->used);
smp_mb__after_atomic();
if (i + 1 == n->pos)
n->pos--;
set->elements--;
#ifdef IP_SET_HASH_WITH_NETS
for (j = 0; j < IPSET_NET_COUNT; j++)
mtype_del_cidr(h, NCIDR_PUT(DCIDR_GET(d->cidr, j)),
j);
#endif
ip_set_ext_destroy(set, data);
for (; i < n->pos; i++) {
if (!test_bit(i, n->used))
k++;
}
if (n->pos == 0 && k == 0) {
set->ext_size -= ext_size(n->size, dsize);
rcu_assign_pointer(hbucket(t, key), NULL);
kfree_rcu(n, rcu);
} else if (k >= AHASH_INIT_SIZE) {
struct hbucket *tmp = kzalloc(sizeof(*tmp) +
(n->size - AHASH_INIT_SIZE) * dsize,
GFP_ATOMIC);
if (!tmp)
goto out;
tmp->size = n->size - AHASH_INIT_SIZE;
for (j = 0, k = 0; j < n->pos; j++) {
if (!test_bit(j, n->used))
continue;
data = ahash_data(n, j, dsize);
memcpy(tmp->value + k * dsize, data, dsize);
set_bit(k, tmp->used);
k++;
}
tmp->pos = k;
set->ext_size -= ext_size(AHASH_INIT_SIZE, dsize);
rcu_assign_pointer(hbucket(t, key), tmp);
kfree_rcu(n, rcu);
}
goto out;
}
out:
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 (!ip_set_match_extensions(set, ext, mext, flags, data))
return 0;
/* nomatch entries return -ENOTEMPTY */
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 ret, i, j = 0, k;
#else
int ret, i, j = 0;
#endif
u32 key, multi = 0;
pr_debug("test by nets\n");
for (; j < NLEN && h->nets[j].cidr[0] && !multi; j++) {
#if IPSET_NET_COUNT == 2
mtype_data_reset_elem(d, &orig);
mtype_data_netmask(d, NCIDR_GET(h->nets[j].cidr[0]), false);
for (k = 0; k < NLEN && h->nets[k].cidr[1] && !multi;
k++) {
mtype_data_netmask(d, NCIDR_GET(h->nets[k].cidr[1]),
true);
#else
mtype_data_netmask(d, NCIDR_GET(h->nets[j].cidr[0]));
#endif
key = HKEY(d, h->initval, t->htable_bits);
n = rcu_dereference_bh(hbucket(t, key));
if (!n)
continue;
for (i = 0; i < n->pos; i++) {
if (!test_bit(i, n->used))
continue;
data = ahash_data(n, i, set->dsize);
if (!mtype_data_equal(data, d, &multi))
continue;
ret = mtype_data_match(data, ext, mext, set, flags);
if (ret != 0)
return ret;
#ifdef IP_SET_HASH_WITH_MULTI
/* No match, reset multiple match flag */
multi = 0;
#endif
}
#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;
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 (DCIDR_GET(d->cidr, i) != HOST_MASK)
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 = rcu_dereference_bh(hbucket(t, key));
if (!n) {
ret = 0;
goto out;
}
for (i = 0; i < n->pos; i++) {
if (!test_bit(i, n->used))
continue;
data = ahash_data(n, i, set->dsize);
if (!mtype_data_equal(data, d, &multi))
continue;
ret = mtype_data_match(data, ext, mext, set, flags);
if (ret != 0)
goto out;
}
out:
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)
{
struct htype *h = set->data;
const struct htable *t;
struct nlattr *nested;
size_t memsize;
u8 htable_bits;
/* If any members have expired, set->elements will be wrong
* mytype_expire function will update it with the right count.
* we do not hold set->lock here, so grab it first.
* set->elements can still be incorrect in the case of a huge set,
* because elements might time out during the listing.
*/
if (SET_WITH_TIMEOUT(set)) {
spin_lock_bh(&set->lock);
mtype_expire(set, h);
spin_unlock_bh(&set->lock);
}
rcu_read_lock_bh();
t = rcu_dereference_bh_nfnl(h->table);
memsize = mtype_ahash_memsize(h, t) + set->ext_size;
htable_bits = t->htable_bits;
rcu_read_unlock_bh();
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(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
#ifdef IP_SET_HASH_WITH_MARKMASK
if (nla_put_u32(skb, IPSET_ATTR_MARKMASK, h->markmask))
goto nla_put_failure;
#endif
if (nla_put_net32(skb, IPSET_ATTR_REFERENCES, htonl(set->ref)) ||
nla_put_net32(skb, IPSET_ATTR_MEMSIZE, htonl(memsize)) ||
nla_put_net32(skb, IPSET_ATTR_ELEMENTS, htonl(set->elements)))
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;
}
/* Make possible to run dumping parallel with resizing */
static void
mtype_uref(struct ip_set *set, struct netlink_callback *cb, bool start)
{
struct htype *h = set->data;
struct htable *t;
if (start) {
rcu_read_lock_bh();
t = rcu_dereference_bh_nfnl(h->table);
atomic_inc(&t->uref);
cb->args[IPSET_CB_PRIVATE] = (unsigned long)t;
rcu_read_unlock_bh();
} else if (cb->args[IPSET_CB_PRIVATE]) {
t = (struct htable *)cb->args[IPSET_CB_PRIVATE];
if (atomic_dec_and_test(&t->uref) && atomic_read(&t->ref)) {
/* Resizing didn't destroy the hash table */
pr_debug("Table destroy by dump: %p\n", t);
mtype_ahash_destroy(set, t, false);
}
cb->args[IPSET_CB_PRIVATE] = 0;
}
}
/* 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 htable *t;
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, ret = 0;
atd = ipset_nest_start(skb, IPSET_ATTR_ADT);
if (!atd)
return -EMSGSIZE;
pr_debug("list hash set %s\n", set->name);
t = (const struct htable *)cb->args[IPSET_CB_PRIVATE];
/* Expire may replace a hbucket with another one */
rcu_read_lock();
for (; cb->args[IPSET_CB_ARG0] < jhash_size(t->htable_bits);
cb->args[IPSET_CB_ARG0]++) {
cond_resched_rcu();
incomplete = skb_tail_pointer(skb);
n = rcu_dereference(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);
if (!n)
continue;
for (i = 0; i < n->pos; i++) {
if (!test_bit(i, n->used))
continue;
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);
ret = -EMSGSIZE;
goto out;
}
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;
goto out;
nla_put_failure:
nlmsg_trim(skb, incomplete);
if (unlikely(first == cb->args[IPSET_CB_ARG0])) {
pr_warn("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;
ret = -EMSGSIZE;
} else {
ipset_nest_end(skb, atd);
}
out:
rcu_read_unlock();
return ret;
}
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,
.uref = mtype_uref,
.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;
#ifdef IP_SET_HASH_WITH_MARKMASK
u32 markmask;
#endif
u8 hbits;
#ifdef IP_SET_HASH_WITH_NETMASK
u8 netmask;
#endif
size_t hsize;
struct htype *h;
struct htable *t;
pr_debug("Create set %s with family %s\n",
set->name, set->family == NFPROTO_IPV4 ? "inet" : "inet6");
#ifdef IP_SET_PROTO_UNDEF
if (set->family != NFPROTO_UNSPEC)
return -IPSET_ERR_INVALID_FAMILY;
#else
if (!(set->family == NFPROTO_IPV4 || set->family == NFPROTO_IPV6))
return -IPSET_ERR_INVALID_FAMILY;
#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;
#ifdef IP_SET_HASH_WITH_MARKMASK
/* Separated condition in order to avoid directive in argument list */
if (unlikely(!ip_set_optattr_netorder(tb, IPSET_ATTR_MARKMASK)))
return -IPSET_ERR_PROTOCOL;
markmask = 0xffffffff;
if (tb[IPSET_ATTR_MARKMASK]) {
markmask = ntohl(nla_get_be32(tb[IPSET_ATTR_MARKMASK]));
if (markmask == 0)
return -IPSET_ERR_INVALID_MARKMASK;
}
#endif
#ifdef IP_SET_HASH_WITH_NETMASK
netmask = set->family == NFPROTO_IPV4 ? 32 : 128;
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
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]);
hsize = sizeof(*h);
h = kzalloc(hsize, GFP_KERNEL);
if (!h)
return -ENOMEM;
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;
}
h->maxelem = maxelem;
#ifdef IP_SET_HASH_WITH_NETMASK
h->netmask = netmask;
#endif
#ifdef IP_SET_HASH_WITH_MARKMASK
h->markmask = markmask;
#endif
get_random_bytes(&h->initval, sizeof(h->initval));
t->htable_bits = hbits;
RCU_INIT_POINTER(h->table, t);
h->set = set;
set->data = h;
#ifndef IP_SET_PROTO_UNDEF
if (set->family == NFPROTO_IPV4) {
#endif
set->variant = &IPSET_TOKEN(HTYPE, 4_variant);
set->dsize = ip_set_elem_len(set, tb,
sizeof(struct IPSET_TOKEN(HTYPE, 4_elem)),
__alignof__(struct IPSET_TOKEN(HTYPE, 4_elem)));
#ifndef IP_SET_PROTO_UNDEF
} else {
set->variant = &IPSET_TOKEN(HTYPE, 6_variant);
set->dsize = ip_set_elem_len(set, tb,
sizeof(struct IPSET_TOKEN(HTYPE, 6_elem)),
__alignof__(struct IPSET_TOKEN(HTYPE, 6_elem)));
}
#endif
set->timeout = IPSET_NO_TIMEOUT;
if (tb[IPSET_ATTR_TIMEOUT]) {
set->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]);
#ifndef IP_SET_PROTO_UNDEF
if (set->family == NFPROTO_IPV4)
#endif
IPSET_TOKEN(HTYPE, 4_gc_init)(set,
IPSET_TOKEN(HTYPE, 4_gc));
#ifndef IP_SET_PROTO_UNDEF
else
IPSET_TOKEN(HTYPE, 6_gc_init)(set,
IPSET_TOKEN(HTYPE, 6_gc));
#endif
}
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 */
#undef HKEY_DATALEN