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 29 MODULE_LICENSE("GPL"); 30 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>"); 31 IP_SET_MODULE_DESC("bitmap:ip,mac", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX); 32 MODULE_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 38 enum { 39 MAC_UNSET, /* element is set, without MAC */ 40 MAC_FILLED, /* element is set with MAC */ 41 }; 42 43 /* Type structure */ 44 struct 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 */ 57 struct bitmap_ipmac_adt_elem { 58 unsigned char ether[ETH_ALEN] __aligned(2); 59 u16 id; 60 u16 add_mac; 61 }; 62 63 struct bitmap_ipmac_elem { 64 unsigned char ether[ETH_ALEN]; 65 unsigned char filled; 66 } __aligned(__alignof__(u64)); 67 68 static u32 69 ip_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 82 static int 83 bitmap_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(e->ether, elem->ether); 93 /* Trigger kernel to fill out the ethernet address */ 94 return -EAGAIN; 95 } 96 97 static int 98 bitmap_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 } 108 109 static int 110 bitmap_ipmac_is_filled(const struct bitmap_ipmac_elem *elem) 111 { 112 return elem->filled == MAC_FILLED; 113 } 114 115 static int 116 bitmap_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, 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, t); 136 else 137 *timeout = t; 138 } 139 return 0; 140 } 141 142 static int 143 bitmap_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(e->ether, elem->ether)) { 154 /* memcpy isn't atomic */ 155 clear_bit(e->id, map->members); 156 smp_mb__after_atomic(); 157 ether_addr_copy(elem->ether, 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(e->id, map->members); 165 smp_mb__after_atomic(); 166 ether_addr_copy(elem->ether, 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(elem->ether, 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 } 179 180 static int 181 bitmap_ipmac_do_del(const struct bitmap_ipmac_adt_elem *e, 182 struct bitmap_ipmac *map) 183 { 184 return !test_and_clear_bit(e->id, map->members); 185 } 186 187 static int 188 bitmap_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, IPSET_ATTR_IP, 195 htonl(map->first_ip + id)) || 196 (elem->filled == MAC_FILLED && 197 nla_put(skb, IPSET_ATTR_ETHER, ETH_ALEN, elem->ether)); 198 } 199 200 static int 201 bitmap_ipmac_do_head(struct sk_buff *skb, const struct bitmap_ipmac *map) 202 { 203 return nla_put_ipaddr4(skb, IPSET_ATTR_IP, htonl(map->first_ip)) || 204 nla_put_ipaddr4(skb, IPSET_ATTR_IP_TO, htonl(map->last_ip)); 205 } 206 207 static int 208 bitmap_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(map, ip); 228 229 if (opt->flags & IPSET_DIM_TWO_SRC) 230 ether_addr_copy(e.ether, eth_hdr(skb)->h_source); 231 else 232 ether_addr_copy(e.ether, eth_hdr(skb)->h_dest); 233 234 if (is_zero_ether_addr(e.ether)) 235 return -EINVAL; 236 237 return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags); 238 } 239 240 static int 241 bitmap_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(tb[IPSET_ATTR_LINENO]); 253 254 if (unlikely(!tb[IPSET_ATTR_IP])) 255 return -IPSET_ERR_PROTOCOL; 256 257 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip); 258 if (ret) 259 return ret; 260 261 ret = ip_set_get_extensions(set, tb, &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(map, ip); 269 if (tb[IPSET_ATTR_ETHER]) { 270 if (nla_len(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 } 279 280 static bool 281 bitmap_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 */ 297 298 static bool 299 init_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(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 } 316 317 static int 318 bitmap_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(tb[IPSET_ATTR_IP], &first_ip); 332 if (ret) 333 return ret; 334 335 if (tb[IPSET_ATTR_IP_TO]) { 336 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &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(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 sizeof(struct bitmap_ipmac_elem), 358 __alignof__(struct bitmap_ipmac_elem)); 359 map = ip_set_alloc(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(map); 367 return -ENOMEM; 368 } 369 if (tb[IPSET_ATTR_TIMEOUT]) { 370 set->timeout = ip_set_timeout_uget(tb[IPSET_ATTR_TIMEOUT]); 371 bitmap_ipmac_gc_init(set, bitmap_ipmac_gc); 372 } 373 return 0; 374 } 375 376 static 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 }; 408 409 static int __init 410 bitmap_ipmac_init(void) 411 { 412 return ip_set_type_register(&bitmap_ipmac_type); 413 } 414 415 static void __exit 416 bitmap_ipmac_fini(void) 417 { 418 rcu_barrier(); 419 ip_set_type_unregister(&bitmap_ipmac_type); 420 } 421 422 module_init(bitmap_ipmac_init); 423 module_exit(bitmap_ipmac_fini); 424