1// SPDX-License-Identifier: GPL-2.0-only
2/* Copyright (C) 2000-2002 Joakim Axelsson <gozem@linux.nu>
3 * Patrick Schaaf <bof@bof.de>
4 * Martin Josefsson <gandalf@wlug.westbo.se>
5 */
6
7/* Kernel module implementing an IP set type: the bitmap:ip,mac type */
8
9#include <linux/module.h>
10#include <linux/ip.h>
11#include <linux/etherdevice.h>
12#include <linux/skbuff.h>
13#include <linux/errno.h>
14#include <linux/if_ether.h>
15#include <linux/netlink.h>
16#include <linux/jiffies.h>
17#include <linux/timer.h>
18#include <net/netlink.h>
19
20#include <linux/netfilter/ipset/pfxlen.h>
21#include <linux/netfilter/ipset/ip_set.h>
22#include <linux/netfilter/ipset/ip_set_bitmap.h>
23
24#define IPSET_TYPE_REV_MIN 0
25/* 1 Counter support added */
26/* 2 Comment support added */
27#define IPSET_TYPE_REV_MAX 3 /* skbinfo support added */
28
29MODULE_LICENSE("GPL");
30MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
31IP_SET_MODULE_DESC("bitmap:ip,mac", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
32MODULE_ALIAS("ip_set_bitmap:ip,mac");
33
34#define MTYPE bitmap_ipmac
35#define HOST_MASK 32
36#define IP_SET_BITMAP_STORED_TIMEOUT
37
38enum {
39 MAC_UNSET, /* element is set, without MAC */
40 MAC_FILLED, /* element is set with MAC */
41};
42
43/* Type structure */
44struct bitmap_ipmac {
45 unsigned long *members; /* the set members */
46 u32 first_ip; /* host byte order, included in range */
47 u32 last_ip; /* host byte order, included in range */
48 u32 elements; /* number of max elements in the set */
49 size_t memsize; /* members size */
50 struct timer_list gc; /* garbage collector */
51 struct ip_set *set; /* attached to this ip_set */
52 unsigned char extensions[] /* MAC + data extensions */
53 __aligned(__alignof__(u64));
54};
55
56/* ADT structure for generic function args */
57struct bitmap_ipmac_adt_elem {
58 unsigned char ether[ETH_ALEN] __aligned(2);
59 u16 id;
60 u16 add_mac;
61};
62
63struct bitmap_ipmac_elem {
64 unsigned char ether[ETH_ALEN];
65 unsigned char filled;
66} __aligned(__alignof__(u64));
67
68static u32
69ip_to_id(const struct bitmap_ipmac *m, u32 ip)
70{
71 return ip - m->first_ip;
72}
73
74#define get_elem(extensions, id, dsize) \
75 (struct bitmap_ipmac_elem *)(extensions + (id) * (dsize))
76
77#define get_const_elem(extensions, id, dsize) \
78 (const struct bitmap_ipmac_elem *)(extensions + (id) * (dsize))
79
80/* Common functions */
81
82static int
83bitmap_ipmac_do_test(const struct bitmap_ipmac_adt_elem *e,
84 const struct bitmap_ipmac *map, size_t dsize)
85{
86 const struct bitmap_ipmac_elem *elem;
87
88 if (!test_bit(e->id, map->members))
89 return 0;
90 elem = get_const_elem(map->extensions, e->id, dsize);
91 if (e->add_mac && elem->filled == MAC_FILLED)
92 return ether_addr_equal(addr1: e->ether, addr2: elem->ether);
93 /* Trigger kernel to fill out the ethernet address */
94 return -EAGAIN;
95}
96
97static int
98bitmap_ipmac_gc_test(u16 id, const struct bitmap_ipmac *map, size_t dsize)
99{
100 const struct bitmap_ipmac_elem *elem;
101
102 if (!test_bit(id, map->members))
103 return 0;
104 elem = get_const_elem(map->extensions, id, dsize);
105 /* Timer not started for the incomplete elements */
106 return elem->filled == MAC_FILLED;
107}
108
109static int
110bitmap_ipmac_is_filled(const struct bitmap_ipmac_elem *elem)
111{
112 return elem->filled == MAC_FILLED;
113}
114
115static int
116bitmap_ipmac_add_timeout(unsigned long *timeout,
117 const struct bitmap_ipmac_adt_elem *e,
118 const struct ip_set_ext *ext, struct ip_set *set,
119 struct bitmap_ipmac *map, int mode)
120{
121 u32 t = ext->timeout;
122
123 if (mode == IPSET_ADD_START_STORED_TIMEOUT) {
124 if (t == set->timeout)
125 /* Timeout was not specified, get stored one */
126 t = *timeout;
127 ip_set_timeout_set(timeout, value: t);
128 } else {
129 /* If MAC is unset yet, we store plain timeout value
130 * because the timer is not activated yet
131 * and we can reuse it later when MAC is filled out,
132 * possibly by the kernel
133 */
134 if (e->add_mac)
135 ip_set_timeout_set(timeout, value: t);
136 else
137 *timeout = t;
138 }
139 return 0;
140}
141
142static int
143bitmap_ipmac_do_add(const struct bitmap_ipmac_adt_elem *e,
144 struct bitmap_ipmac *map, u32 flags, size_t dsize)
145{
146 struct bitmap_ipmac_elem *elem;
147
148 elem = get_elem(map->extensions, e->id, dsize);
149 if (test_bit(e->id, map->members)) {
150 if (elem->filled == MAC_FILLED) {
151 if (e->add_mac &&
152 (flags & IPSET_FLAG_EXIST) &&
153 !ether_addr_equal(addr1: e->ether, addr2: elem->ether)) {
154 /* memcpy isn't atomic */
155 clear_bit(nr: e->id, addr: map->members);
156 smp_mb__after_atomic();
157 ether_addr_copy(dst: elem->ether, src: e->ether);
158 }
159 return IPSET_ADD_FAILED;
160 } else if (!e->add_mac)
161 /* Already added without ethernet address */
162 return IPSET_ADD_FAILED;
163 /* Fill the MAC address and trigger the timer activation */
164 clear_bit(nr: e->id, addr: map->members);
165 smp_mb__after_atomic();
166 ether_addr_copy(dst: elem->ether, src: e->ether);
167 elem->filled = MAC_FILLED;
168 return IPSET_ADD_START_STORED_TIMEOUT;
169 } else if (e->add_mac) {
170 /* We can store MAC too */
171 ether_addr_copy(dst: elem->ether, src: e->ether);
172 elem->filled = MAC_FILLED;
173 return 0;
174 }
175 elem->filled = MAC_UNSET;
176 /* MAC is not stored yet, don't start timer */
177 return IPSET_ADD_STORE_PLAIN_TIMEOUT;
178}
179
180static int
181bitmap_ipmac_do_del(const struct bitmap_ipmac_adt_elem *e,
182 struct bitmap_ipmac *map)
183{
184 return !test_and_clear_bit(nr: e->id, addr: map->members);
185}
186
187static int
188bitmap_ipmac_do_list(struct sk_buff *skb, const struct bitmap_ipmac *map,
189 u32 id, size_t dsize)
190{
191 const struct bitmap_ipmac_elem *elem =
192 get_const_elem(map->extensions, id, dsize);
193
194 return nla_put_ipaddr4(skb, type: IPSET_ATTR_IP,
195 htonl(map->first_ip + id)) ||
196 (elem->filled == MAC_FILLED &&
197 nla_put(skb, attrtype: IPSET_ATTR_ETHER, ETH_ALEN, data: elem->ether));
198}
199
200static int
201bitmap_ipmac_do_head(struct sk_buff *skb, const struct bitmap_ipmac *map)
202{
203 return nla_put_ipaddr4(skb, type: IPSET_ATTR_IP, htonl(map->first_ip)) ||
204 nla_put_ipaddr4(skb, type: IPSET_ATTR_IP_TO, htonl(map->last_ip));
205}
206
207static int
208bitmap_ipmac_kadt(struct ip_set *set, const struct sk_buff *skb,
209 const struct xt_action_param *par,
210 enum ipset_adt adt, struct ip_set_adt_opt *opt)
211{
212 struct bitmap_ipmac *map = set->data;
213 ipset_adtfn adtfn = set->variant->adt[adt];
214 struct bitmap_ipmac_adt_elem e = { .id = 0, .add_mac = 1 };
215 struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
216 u32 ip;
217
218 ip = ntohl(ip4addr(skb, opt->flags & IPSET_DIM_ONE_SRC));
219 if (ip < map->first_ip || ip > map->last_ip)
220 return -IPSET_ERR_BITMAP_RANGE;
221
222 /* Backward compatibility: we don't check the second flag */
223 if (skb_mac_header(skb) < skb->head ||
224 (skb_mac_header(skb) + ETH_HLEN) > skb->data)
225 return -EINVAL;
226
227 e.id = ip_to_id(m: map, ip);
228
229 if (opt->flags & IPSET_DIM_TWO_SRC)
230 ether_addr_copy(dst: e.ether, src: eth_hdr(skb)->h_source);
231 else
232 ether_addr_copy(dst: e.ether, src: eth_hdr(skb)->h_dest);
233
234 if (is_zero_ether_addr(addr: e.ether))
235 return -EINVAL;
236
237 return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
238}
239
240static int
241bitmap_ipmac_uadt(struct ip_set *set, struct nlattr *tb[],
242 enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
243{
244 const struct bitmap_ipmac *map = set->data;
245 ipset_adtfn adtfn = set->variant->adt[adt];
246 struct bitmap_ipmac_adt_elem e = { .id = 0 };
247 struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
248 u32 ip = 0;
249 int ret = 0;
250
251 if (tb[IPSET_ATTR_LINENO])
252 *lineno = nla_get_u32(nla: tb[IPSET_ATTR_LINENO]);
253
254 if (unlikely(!tb[IPSET_ATTR_IP]))
255 return -IPSET_ERR_PROTOCOL;
256
257 ret = ip_set_get_hostipaddr4(nla: tb[IPSET_ATTR_IP], ipaddr: &ip);
258 if (ret)
259 return ret;
260
261 ret = ip_set_get_extensions(set, tb, ext: &ext);
262 if (ret)
263 return ret;
264
265 if (ip < map->first_ip || ip > map->last_ip)
266 return -IPSET_ERR_BITMAP_RANGE;
267
268 e.id = ip_to_id(m: map, ip);
269 if (tb[IPSET_ATTR_ETHER]) {
270 if (nla_len(nla: tb[IPSET_ATTR_ETHER]) != ETH_ALEN)
271 return -IPSET_ERR_PROTOCOL;
272 memcpy(e.ether, nla_data(tb[IPSET_ATTR_ETHER]), ETH_ALEN);
273 e.add_mac = 1;
274 }
275 ret = adtfn(set, &e, &ext, &ext, flags);
276
277 return ip_set_eexist(ret, flags) ? 0 : ret;
278}
279
280static bool
281bitmap_ipmac_same_set(const struct ip_set *a, const struct ip_set *b)
282{
283 const struct bitmap_ipmac *x = a->data;
284 const struct bitmap_ipmac *y = b->data;
285
286 return x->first_ip == y->first_ip &&
287 x->last_ip == y->last_ip &&
288 a->timeout == b->timeout &&
289 a->extensions == b->extensions;
290}
291
292/* Plain variant */
293
294#include "ip_set_bitmap_gen.h"
295
296/* Create bitmap:ip,mac type of sets */
297
298static bool
299init_map_ipmac(struct ip_set *set, struct bitmap_ipmac *map,
300 u32 first_ip, u32 last_ip, u32 elements)
301{
302 map->members = bitmap_zalloc(nbits: elements, GFP_KERNEL | __GFP_NOWARN);
303 if (!map->members)
304 return false;
305 map->first_ip = first_ip;
306 map->last_ip = last_ip;
307 map->elements = elements;
308 set->timeout = IPSET_NO_TIMEOUT;
309
310 map->set = set;
311 set->data = map;
312 set->family = NFPROTO_IPV4;
313
314 return true;
315}
316
317static int
318bitmap_ipmac_create(struct net *net, struct ip_set *set, struct nlattr *tb[],
319 u32 flags)
320{
321 u32 first_ip = 0, last_ip = 0;
322 u64 elements;
323 struct bitmap_ipmac *map;
324 int ret;
325
326 if (unlikely(!tb[IPSET_ATTR_IP] ||
327 !ip_set_optattr_netorder(tb, IPSET_ATTR_TIMEOUT) ||
328 !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
329 return -IPSET_ERR_PROTOCOL;
330
331 ret = ip_set_get_hostipaddr4(nla: tb[IPSET_ATTR_IP], ipaddr: &first_ip);
332 if (ret)
333 return ret;
334
335 if (tb[IPSET_ATTR_IP_TO]) {
336 ret = ip_set_get_hostipaddr4(nla: tb[IPSET_ATTR_IP_TO], ipaddr: &last_ip);
337 if (ret)
338 return ret;
339 if (first_ip > last_ip)
340 swap(first_ip, last_ip);
341 } else if (tb[IPSET_ATTR_CIDR]) {
342 u8 cidr = nla_get_u8(nla: tb[IPSET_ATTR_CIDR]);
343
344 if (cidr >= HOST_MASK)
345 return -IPSET_ERR_INVALID_CIDR;
346 ip_set_mask_from_to(first_ip, last_ip, cidr);
347 } else {
348 return -IPSET_ERR_PROTOCOL;
349 }
350
351 elements = (u64)last_ip - first_ip + 1;
352
353 if (elements > IPSET_BITMAP_MAX_RANGE + 1)
354 return -IPSET_ERR_BITMAP_RANGE_SIZE;
355
356 set->dsize = ip_set_elem_len(set, tb,
357 len: sizeof(struct bitmap_ipmac_elem),
358 align: __alignof__(struct bitmap_ipmac_elem));
359 map = ip_set_alloc(size: sizeof(*map) + elements * set->dsize);
360 if (!map)
361 return -ENOMEM;
362
363 map->memsize = BITS_TO_LONGS(elements) * sizeof(unsigned long);
364 set->variant = &bitmap_ipmac;
365 if (!init_map_ipmac(set, map, first_ip, last_ip, elements)) {
366 ip_set_free(members: map);
367 return -ENOMEM;
368 }
369 if (tb[IPSET_ATTR_TIMEOUT]) {
370 set->timeout = ip_set_timeout_uget(tb: tb[IPSET_ATTR_TIMEOUT]);
371 bitmap_ipmac_gc_init(set, gc: bitmap_ipmac_gc);
372 }
373 return 0;
374}
375
376static struct ip_set_type bitmap_ipmac_type = {
377 .name = "bitmap:ip,mac",
378 .protocol = IPSET_PROTOCOL,
379 .features = IPSET_TYPE_IP | IPSET_TYPE_MAC,
380 .dimension = IPSET_DIM_TWO,
381 .family = NFPROTO_IPV4,
382 .revision_min = IPSET_TYPE_REV_MIN,
383 .revision_max = IPSET_TYPE_REV_MAX,
384 .create = bitmap_ipmac_create,
385 .create_policy = {
386 [IPSET_ATTR_IP] = { .type = NLA_NESTED },
387 [IPSET_ATTR_IP_TO] = { .type = NLA_NESTED },
388 [IPSET_ATTR_CIDR] = { .type = NLA_U8 },
389 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
390 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
391 },
392 .adt_policy = {
393 [IPSET_ATTR_IP] = { .type = NLA_NESTED },
394 [IPSET_ATTR_ETHER] = { .type = NLA_BINARY,
395 .len = ETH_ALEN },
396 [IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
397 [IPSET_ATTR_LINENO] = { .type = NLA_U32 },
398 [IPSET_ATTR_BYTES] = { .type = NLA_U64 },
399 [IPSET_ATTR_PACKETS] = { .type = NLA_U64 },
400 [IPSET_ATTR_COMMENT] = { .type = NLA_NUL_STRING,
401 .len = IPSET_MAX_COMMENT_SIZE },
402 [IPSET_ATTR_SKBMARK] = { .type = NLA_U64 },
403 [IPSET_ATTR_SKBPRIO] = { .type = NLA_U32 },
404 [IPSET_ATTR_SKBQUEUE] = { .type = NLA_U16 },
405 },
406 .me = THIS_MODULE,
407};
408
409static int __init
410bitmap_ipmac_init(void)
411{
412 return ip_set_type_register(set_type: &bitmap_ipmac_type);
413}
414
415static void __exit
416bitmap_ipmac_fini(void)
417{
418 rcu_barrier();
419 ip_set_type_unregister(set_type: &bitmap_ipmac_type);
420}
421
422module_init(bitmap_ipmac_init);
423module_exit(bitmap_ipmac_fini);
424

source code of linux/net/netfilter/ipset/ip_set_bitmap_ipmac.c