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/*-
* Copyright (c) 2004 Ruslan Ermilov and Vsevolod Lobko.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Lookup table support for ipfw
*
* Lookup tables are implemented (at the moment) using the radix
* tree used for routing tables. Tables store key-value entries, where
* keys are network prefixes (addr/masklen), and values are integers.
* As a degenerate case we can interpret keys as 32-bit integers
* (with a /32 mask).
*
* The table is protected by the IPFW lock even for manipulation coming
* from userland, because operations are typically fast.
*/
#if !defined(KLD_MODULE)
#include "opt_ipfw.h"
#include "opt_ipdivert.h"
#include "opt_ipdn.h"
#include "opt_inet.h"
#ifndef INET
#error IPFIREWALL requires INET.
#endif /* INET */
#endif
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#include <sys/socket.h>
#include <net/if.h> /* ip_fw.h requires IFNAMSIZ */
#include <net/radix.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/ip_var.h> /* struct ipfw_rule_ref */
#include <netinet/ip_fw.h>
#include <sys/queue.h> /* LIST_HEAD */
#include <netinet/ipfw/ip_fw_private.h>
#ifdef MAC
#include <security/mac/mac_framework.h>
#endif
MALLOC_DEFINE(M_IPFW_TBL, "ipfw_tbl", "IpFw tables");
struct table_entry {
struct radix_node rn[2];
struct sockaddr_in addr, mask;
u_int32_t value;
};
/*
* The radix code expects addr and mask to be array of bytes,
* with the first byte being the length of the array. rn_inithead
* is called with the offset in bits of the lookup key within the
* array. If we use a sockaddr_in as the underlying type,
* sin_len is conveniently located at offset 0, sin_addr is at
* offset 4 and normally aligned.
* But for portability, let's avoid assumption and make the code explicit
*/
#define KEY_LEN(v) *((uint8_t *)&(v))
#define KEY_OFS (8*offsetof(struct sockaddr_in, sin_addr))
int
ipfw_add_table_entry(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
uint8_t mlen, uint32_t value)
{
struct radix_node_head *rnh;
struct table_entry *ent;
struct radix_node *rn;
if (tbl >= IPFW_TABLES_MAX)
return (EINVAL);
rnh = ch->tables[tbl];
ent = malloc(sizeof(*ent), M_IPFW_TBL, M_NOWAIT | M_ZERO);
if (ent == NULL)
return (ENOMEM);
ent->value = value;
KEY_LEN(ent->addr) = KEY_LEN(ent->mask) = 8;
ent->mask.sin_addr.s_addr = htonl(mlen ? ~((1 << (32 - mlen)) - 1) : 0);
ent->addr.sin_addr.s_addr = addr & ent->mask.sin_addr.s_addr;
IPFW_WLOCK(ch);
rn = rnh->rnh_addaddr(&ent->addr, &ent->mask, rnh, (void *)ent);
if (rn == NULL) {
IPFW_WUNLOCK(ch);
free(ent, M_IPFW_TBL);
return (EEXIST);
}
IPFW_WUNLOCK(ch);
return (0);
}
int
ipfw_del_table_entry(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
uint8_t mlen)
{
struct radix_node_head *rnh;
struct table_entry *ent;
struct sockaddr_in sa, mask;
if (tbl >= IPFW_TABLES_MAX)
return (EINVAL);
rnh = ch->tables[tbl];
KEY_LEN(sa) = KEY_LEN(mask) = 8;
mask.sin_addr.s_addr = htonl(mlen ? ~((1 << (32 - mlen)) - 1) : 0);
sa.sin_addr.s_addr = addr & mask.sin_addr.s_addr;
IPFW_WLOCK(ch);
ent = (struct table_entry *)rnh->rnh_deladdr(&sa, &mask, rnh);
if (ent == NULL) {
IPFW_WUNLOCK(ch);
return (ESRCH);
}
IPFW_WUNLOCK(ch);
free(ent, M_IPFW_TBL);
return (0);
}
static int
flush_table_entry(struct radix_node *rn, void *arg)
{
struct radix_node_head * const rnh = arg;
struct table_entry *ent;
ent = (struct table_entry *)
rnh->rnh_deladdr(rn->rn_key, rn->rn_mask, rnh);
if (ent != NULL)
free(ent, M_IPFW_TBL);
return (0);
}
int
ipfw_flush_table(struct ip_fw_chain *ch, uint16_t tbl)
{
struct radix_node_head *rnh;
IPFW_WLOCK_ASSERT(ch);
if (tbl >= IPFW_TABLES_MAX)
return (EINVAL);
rnh = ch->tables[tbl];
KASSERT(rnh != NULL, ("NULL IPFW table"));
rnh->rnh_walktree(rnh, flush_table_entry, rnh);
return (0);
}
void
ipfw_flush_tables(struct ip_fw_chain *ch)
{
uint16_t tbl;
IPFW_WLOCK_ASSERT(ch);
for (tbl = 0; tbl < IPFW_TABLES_MAX; tbl++)
ipfw_flush_table(ch, tbl);
}
int
ipfw_init_tables(struct ip_fw_chain *ch)
{
int i;
uint16_t j;
for (i = 0; i < IPFW_TABLES_MAX; i++) {
if (!rn_inithead((void **)&ch->tables[i], KEY_OFS)) {
for (j = 0; j < i; j++) {
(void) ipfw_flush_table(ch, j);
}
return (ENOMEM);
}
}
return (0);
}
int
ipfw_lookup_table(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
uint32_t *val)
{
struct radix_node_head *rnh;
struct table_entry *ent;
struct sockaddr_in sa;
if (tbl >= IPFW_TABLES_MAX)
return (0);
rnh = ch->tables[tbl];
KEY_LEN(sa) = 8;
sa.sin_addr.s_addr = addr;
ent = (struct table_entry *)(rnh->rnh_lookup(&sa, NULL, rnh));
if (ent != NULL) {
*val = ent->value;
return (1);
}
return (0);
}
static int
count_table_entry(struct radix_node *rn, void *arg)
{
u_int32_t * const cnt = arg;
(*cnt)++;
return (0);
}
int
ipfw_count_table(struct ip_fw_chain *ch, uint32_t tbl, uint32_t *cnt)
{
struct radix_node_head *rnh;
if (tbl >= IPFW_TABLES_MAX)
return (EINVAL);
rnh = ch->tables[tbl];
*cnt = 0;
rnh->rnh_walktree(rnh, count_table_entry, cnt);
return (0);
}
static int
dump_table_entry(struct radix_node *rn, void *arg)
{
struct table_entry * const n = (struct table_entry *)rn;
ipfw_table * const tbl = arg;
ipfw_table_entry *ent;
if (tbl->cnt == tbl->size)
return (1);
ent = &tbl->ent[tbl->cnt];
ent->tbl = tbl->tbl;
if (in_nullhost(n->mask.sin_addr))
ent->masklen = 0;
else
ent->masklen = 33 - ffs(ntohl(n->mask.sin_addr.s_addr));
ent->addr = n->addr.sin_addr.s_addr;
ent->value = n->value;
tbl->cnt++;
return (0);
}
int
ipfw_dump_table(struct ip_fw_chain *ch, ipfw_table *tbl)
{
struct radix_node_head *rnh;
if (tbl->tbl >= IPFW_TABLES_MAX)
return (EINVAL);
rnh = ch->tables[tbl->tbl];
tbl->cnt = 0;
rnh->rnh_walktree(rnh, dump_table_entry, tbl);
return (0);
}
/* end of file */
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