2 * Copyright (c) 2004 Ruslan Ermilov and Vsevolod Lobko.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
30 * Lookup table support for ipfw
32 * Lookup tables are implemented (at the moment) using the radix
33 * tree used for routing tables. Tables store key-value entries, where
34 * keys are network prefixes (addr/masklen), and values are integers.
35 * As a degenerate case we can interpret keys as 32-bit integers
38 * The table is protected by the IPFW lock even for manipulation coming
39 * from userland, because operations are typically fast.
45 #error IPFIREWALL requires INET.
47 #include "opt_inet6.h"
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/malloc.h>
52 #include <sys/kernel.h>
54 #include <sys/rwlock.h>
55 #include <sys/socket.h>
56 #include <net/if.h> /* ip_fw.h requires IFNAMSIZ */
57 #include <net/radix.h>
58 #include <net/route.h>
61 #include <netinet/in.h>
62 #include <netinet/ip_var.h> /* struct ipfw_rule_ref */
63 #include <netinet/ip_fw.h>
64 #include <sys/queue.h> /* LIST_HEAD */
65 #include <netinet/ipfw/ip_fw_private.h>
68 #include <security/mac/mac_framework.h>
71 MALLOC_DEFINE(M_IPFW_TBL, "ipfw_tbl", "IpFw tables");
74 struct radix_node rn[2];
75 struct sockaddr_in addr, mask;
80 * The radix code expects addr and mask to be array of bytes,
81 * with the first byte being the length of the array. rn_inithead
82 * is called with the offset in bits of the lookup key within the
83 * array. If we use a sockaddr_in as the underlying type,
84 * sin_len is conveniently located at offset 0, sin_addr is at
85 * offset 4 and normally aligned.
86 * But for portability, let's avoid assumption and make the code explicit
88 #define KEY_LEN(v) *((uint8_t *)&(v))
89 #define KEY_OFS (8*offsetof(struct sockaddr_in, sin_addr))
92 ipfw_add_table_entry(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
93 uint8_t mlen, uint32_t value)
95 struct radix_node_head *rnh;
96 struct table_entry *ent;
97 struct radix_node *rn;
99 if (tbl >= IPFW_TABLES_MAX)
101 rnh = ch->tables[tbl];
102 ent = malloc(sizeof(*ent), M_IPFW_TBL, M_NOWAIT | M_ZERO);
106 KEY_LEN(ent->addr) = KEY_LEN(ent->mask) = 8;
107 ent->mask.sin_addr.s_addr = htonl(mlen ? ~((1 << (32 - mlen)) - 1) : 0);
108 ent->addr.sin_addr.s_addr = addr & ent->mask.sin_addr.s_addr;
110 rn = rnh->rnh_addaddr(&ent->addr, &ent->mask, rnh, (void *)ent);
113 free(ent, M_IPFW_TBL);
121 ipfw_del_table_entry(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
124 struct radix_node_head *rnh;
125 struct table_entry *ent;
126 struct sockaddr_in sa, mask;
128 if (tbl >= IPFW_TABLES_MAX)
130 rnh = ch->tables[tbl];
131 KEY_LEN(sa) = KEY_LEN(mask) = 8;
132 mask.sin_addr.s_addr = htonl(mlen ? ~((1 << (32 - mlen)) - 1) : 0);
133 sa.sin_addr.s_addr = addr & mask.sin_addr.s_addr;
135 ent = (struct table_entry *)rnh->rnh_deladdr(&sa, &mask, rnh);
141 free(ent, M_IPFW_TBL);
146 flush_table_entry(struct radix_node *rn, void *arg)
148 struct radix_node_head * const rnh = arg;
149 struct table_entry *ent;
151 ent = (struct table_entry *)
152 rnh->rnh_deladdr(rn->rn_key, rn->rn_mask, rnh);
154 free(ent, M_IPFW_TBL);
159 ipfw_flush_table(struct ip_fw_chain *ch, uint16_t tbl)
161 struct radix_node_head *rnh;
163 IPFW_WLOCK_ASSERT(ch);
165 if (tbl >= IPFW_TABLES_MAX)
167 rnh = ch->tables[tbl];
168 KASSERT(rnh != NULL, ("NULL IPFW table"));
169 rnh->rnh_walktree(rnh, flush_table_entry, rnh);
174 ipfw_destroy_tables(struct ip_fw_chain *ch)
177 struct radix_node_head *rnh;
179 IPFW_WLOCK_ASSERT(ch);
181 for (tbl = 0; tbl < IPFW_TABLES_MAX; tbl++) {
182 ipfw_flush_table(ch, tbl);
183 rnh = ch->tables[tbl];
184 rn_detachhead((void **)&rnh);
189 ipfw_init_tables(struct ip_fw_chain *ch)
194 for (i = 0; i < IPFW_TABLES_MAX; i++) {
195 if (!rn_inithead((void **)&ch->tables[i], KEY_OFS)) {
196 for (j = 0; j < i; j++) {
197 (void) ipfw_flush_table(ch, j);
206 ipfw_lookup_table(struct ip_fw_chain *ch, uint16_t tbl, in_addr_t addr,
209 struct radix_node_head *rnh;
210 struct table_entry *ent;
211 struct sockaddr_in sa;
213 if (tbl >= IPFW_TABLES_MAX)
215 rnh = ch->tables[tbl];
217 sa.sin_addr.s_addr = addr;
218 ent = (struct table_entry *)(rnh->rnh_lookup(&sa, NULL, rnh));
227 count_table_entry(struct radix_node *rn, void *arg)
229 u_int32_t * const cnt = arg;
236 ipfw_count_table(struct ip_fw_chain *ch, uint32_t tbl, uint32_t *cnt)
238 struct radix_node_head *rnh;
240 if (tbl >= IPFW_TABLES_MAX)
242 rnh = ch->tables[tbl];
244 rnh->rnh_walktree(rnh, count_table_entry, cnt);
249 dump_table_entry(struct radix_node *rn, void *arg)
251 struct table_entry * const n = (struct table_entry *)rn;
252 ipfw_table * const tbl = arg;
253 ipfw_table_entry *ent;
255 if (tbl->cnt == tbl->size)
257 ent = &tbl->ent[tbl->cnt];
259 if (in_nullhost(n->mask.sin_addr))
262 ent->masklen = 33 - ffs(ntohl(n->mask.sin_addr.s_addr));
263 ent->addr = n->addr.sin_addr.s_addr;
264 ent->value = n->value;
270 ipfw_dump_table(struct ip_fw_chain *ch, ipfw_table *tbl)
272 struct radix_node_head *rnh;
274 if (tbl->tbl >= IPFW_TABLES_MAX)
276 rnh = ch->tables[tbl->tbl];
278 rnh->rnh_walktree(rnh, dump_table_entry, tbl);