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Linux/net/netfilter/ipset/ip_set_hash_netiface.c

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  1 // SPDX-License-Identifier: GPL-2.0-only
  2 /* Copyright (C) 2011-2013 Jozsef Kadlecsik <kadlec@netfilter.org> */
  3 
  4 /* Kernel module implementing an IP set type: the hash:net,iface type */
  5 
  6 #include <linux/jhash.h>
  7 #include <linux/module.h>
  8 #include <linux/ip.h>
  9 #include <linux/skbuff.h>
 10 #include <linux/errno.h>
 11 #include <linux/random.h>
 12 #include <net/ip.h>
 13 #include <net/ipv6.h>
 14 #include <net/netlink.h>
 15 
 16 #include <linux/netfilter.h>
 17 #include <linux/netfilter_bridge.h>
 18 #include <linux/netfilter/ipset/pfxlen.h>
 19 #include <linux/netfilter/ipset/ip_set.h>
 20 #include <linux/netfilter/ipset/ip_set_hash.h>
 21 
 22 #define IPSET_TYPE_REV_MIN      0
 23 /*                              1    nomatch flag support added */
 24 /*                              2    /0 support added */
 25 /*                              3    Counters support added */
 26 /*                              4    Comments support added */
 27 /*                              5    Forceadd support added */
 28 /*                              6    skbinfo support added */
 29 /*                              7    interface wildcard support added */
 30 #define IPSET_TYPE_REV_MAX      8 /* bucketsize, initval support added */
 31 
 32 MODULE_LICENSE("GPL");
 33 MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@netfilter.org>");
 34 IP_SET_MODULE_DESC("hash:net,iface", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
 35 MODULE_ALIAS("ip_set_hash:net,iface");
 36 
 37 /* Type specific function prefix */
 38 #define HTYPE           hash_netiface
 39 #define IP_SET_HASH_WITH_NETS
 40 #define IP_SET_HASH_WITH_MULTI
 41 #define IP_SET_HASH_WITH_NET0
 42 
 43 #define STRLCPY(a, b)   strlcpy(a, b, IFNAMSIZ)
 44 
 45 /* IPv4 variant */
 46 
 47 struct hash_netiface4_elem_hashed {
 48         __be32 ip;
 49         u8 physdev;
 50         u8 cidr;
 51         u8 nomatch;
 52         u8 elem;
 53 };
 54 
 55 /* Member elements */
 56 struct hash_netiface4_elem {
 57         __be32 ip;
 58         u8 physdev;
 59         u8 cidr;
 60         u8 nomatch;
 61         u8 elem;
 62         u8 wildcard;
 63         char iface[IFNAMSIZ];
 64 };
 65 
 66 /* Common functions */
 67 
 68 static bool
 69 hash_netiface4_data_equal(const struct hash_netiface4_elem *ip1,
 70                           const struct hash_netiface4_elem *ip2,
 71                           u32 *multi)
 72 {
 73         return ip1->ip == ip2->ip &&
 74                ip1->cidr == ip2->cidr &&
 75                (++*multi) &&
 76                ip1->physdev == ip2->physdev &&
 77                (ip1->wildcard ?
 78                 strncmp(ip1->iface, ip2->iface, strlen(ip1->iface)) == 0 :
 79                 strcmp(ip1->iface, ip2->iface) == 0);
 80 }
 81 
 82 static int
 83 hash_netiface4_do_data_match(const struct hash_netiface4_elem *elem)
 84 {
 85         return elem->nomatch ? -ENOTEMPTY : 1;
 86 }
 87 
 88 static void
 89 hash_netiface4_data_set_flags(struct hash_netiface4_elem *elem, u32 flags)
 90 {
 91         elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
 92 }
 93 
 94 static void
 95 hash_netiface4_data_reset_flags(struct hash_netiface4_elem *elem, u8 *flags)
 96 {
 97         swap(*flags, elem->nomatch);
 98 }
 99 
100 static void
101 hash_netiface4_data_netmask(struct hash_netiface4_elem *elem, u8 cidr)
102 {
103         elem->ip &= ip_set_netmask(cidr);
104         elem->cidr = cidr;
105 }
106 
107 static bool
108 hash_netiface4_data_list(struct sk_buff *skb,
109                          const struct hash_netiface4_elem *data)
110 {
111         u32 flags = (data->physdev ? IPSET_FLAG_PHYSDEV : 0) |
112                     (data->wildcard ? IPSET_FLAG_IFACE_WILDCARD : 0);
113 
114         if (data->nomatch)
115                 flags |= IPSET_FLAG_NOMATCH;
116         if (nla_put_ipaddr4(skb, IPSET_ATTR_IP, data->ip) ||
117             nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr) ||
118             nla_put_string(skb, IPSET_ATTR_IFACE, data->iface) ||
119             (flags &&
120              nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
121                 goto nla_put_failure;
122         return false;
123 
124 nla_put_failure:
125         return true;
126 }
127 
128 static void
129 hash_netiface4_data_next(struct hash_netiface4_elem *next,
130                          const struct hash_netiface4_elem *d)
131 {
132         next->ip = d->ip;
133 }
134 
135 #define MTYPE           hash_netiface4
136 #define HOST_MASK       32
137 #define HKEY_DATALEN    sizeof(struct hash_netiface4_elem_hashed)
138 #include "ip_set_hash_gen.h"
139 
140 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
141 static const char *get_physindev_name(const struct sk_buff *skb)
142 {
143         struct net_device *dev = nf_bridge_get_physindev(skb);
144 
145         return dev ? dev->name : NULL;
146 }
147 
148 static const char *get_physoutdev_name(const struct sk_buff *skb)
149 {
150         struct net_device *dev = nf_bridge_get_physoutdev(skb);
151 
152         return dev ? dev->name : NULL;
153 }
154 #endif
155 
156 static int
157 hash_netiface4_kadt(struct ip_set *set, const struct sk_buff *skb,
158                     const struct xt_action_param *par,
159                     enum ipset_adt adt, struct ip_set_adt_opt *opt)
160 {
161         struct hash_netiface4 *h = set->data;
162         ipset_adtfn adtfn = set->variant->adt[adt];
163         struct hash_netiface4_elem e = {
164                 .cidr = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK),
165                 .elem = 1,
166         };
167         struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
168 
169         if (adt == IPSET_TEST)
170                 e.cidr = HOST_MASK;
171 
172         ip4addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip);
173         e.ip &= ip_set_netmask(e.cidr);
174 
175 #define IFACE(dir)      (par->state->dir ? par->state->dir->name : "")
176 #define SRCDIR          (opt->flags & IPSET_DIM_TWO_SRC)
177 
178         if (opt->cmdflags & IPSET_FLAG_PHYSDEV) {
179 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
180                 const char *eiface = SRCDIR ? get_physindev_name(skb) :
181                                               get_physoutdev_name(skb);
182 
183                 if (!eiface)
184                         return -EINVAL;
185                 STRLCPY(e.iface, eiface);
186                 e.physdev = 1;
187 #endif
188         } else {
189                 STRLCPY(e.iface, SRCDIR ? IFACE(in) : IFACE(out));
190         }
191 
192         if (strlen(e.iface) == 0)
193                 return -EINVAL;
194         return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
195 }
196 
197 static int
198 hash_netiface4_uadt(struct ip_set *set, struct nlattr *tb[],
199                     enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
200 {
201         struct hash_netiface4 *h = set->data;
202         ipset_adtfn adtfn = set->variant->adt[adt];
203         struct hash_netiface4_elem e = { .cidr = HOST_MASK, .elem = 1 };
204         struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
205         u32 ip = 0, ip_to = 0;
206         int ret;
207 
208         if (tb[IPSET_ATTR_LINENO])
209                 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
210 
211         if (unlikely(!tb[IPSET_ATTR_IP] ||
212                      !tb[IPSET_ATTR_IFACE] ||
213                      !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
214                 return -IPSET_ERR_PROTOCOL;
215 
216         ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP], &ip);
217         if (ret)
218                 return ret;
219 
220         ret = ip_set_get_extensions(set, tb, &ext);
221         if (ret)
222                 return ret;
223 
224         if (tb[IPSET_ATTR_CIDR]) {
225                 e.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
226                 if (e.cidr > HOST_MASK)
227                         return -IPSET_ERR_INVALID_CIDR;
228         }
229         nla_strscpy(e.iface, tb[IPSET_ATTR_IFACE], IFNAMSIZ);
230 
231         if (tb[IPSET_ATTR_CADT_FLAGS]) {
232                 u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
233 
234                 if (cadt_flags & IPSET_FLAG_PHYSDEV)
235                         e.physdev = 1;
236                 if (cadt_flags & IPSET_FLAG_NOMATCH)
237                         flags |= (IPSET_FLAG_NOMATCH << 16);
238                 if (cadt_flags & IPSET_FLAG_IFACE_WILDCARD)
239                         e.wildcard = 1;
240         }
241         if (adt == IPSET_TEST || !tb[IPSET_ATTR_IP_TO]) {
242                 e.ip = htonl(ip & ip_set_hostmask(e.cidr));
243                 ret = adtfn(set, &e, &ext, &ext, flags);
244                 return ip_set_enomatch(ret, flags, adt, set) ? -ret :
245                        ip_set_eexist(ret, flags) ? 0 : ret;
246         }
247 
248         if (tb[IPSET_ATTR_IP_TO]) {
249                 ret = ip_set_get_hostipaddr4(tb[IPSET_ATTR_IP_TO], &ip_to);
250                 if (ret)
251                         return ret;
252                 if (ip_to < ip)
253                         swap(ip, ip_to);
254                 if (ip + UINT_MAX == ip_to)
255                         return -IPSET_ERR_HASH_RANGE;
256         } else {
257                 ip_set_mask_from_to(ip, ip_to, e.cidr);
258         }
259 
260         if (retried)
261                 ip = ntohl(h->next.ip);
262         do {
263                 e.ip = htonl(ip);
264                 ip = ip_set_range_to_cidr(ip, ip_to, &e.cidr);
265                 ret = adtfn(set, &e, &ext, &ext, flags);
266 
267                 if (ret && !ip_set_eexist(ret, flags))
268                         return ret;
269 
270                 ret = 0;
271         } while (ip++ < ip_to);
272         return ret;
273 }
274 
275 /* IPv6 variant */
276 
277 struct hash_netiface6_elem_hashed {
278         union nf_inet_addr ip;
279         u8 physdev;
280         u8 cidr;
281         u8 nomatch;
282         u8 elem;
283 };
284 
285 struct hash_netiface6_elem {
286         union nf_inet_addr ip;
287         u8 physdev;
288         u8 cidr;
289         u8 nomatch;
290         u8 elem;
291         u8 wildcard;
292         char iface[IFNAMSIZ];
293 };
294 
295 /* Common functions */
296 
297 static bool
298 hash_netiface6_data_equal(const struct hash_netiface6_elem *ip1,
299                           const struct hash_netiface6_elem *ip2,
300                           u32 *multi)
301 {
302         return ipv6_addr_equal(&ip1->ip.in6, &ip2->ip.in6) &&
303                ip1->cidr == ip2->cidr &&
304                (++*multi) &&
305                ip1->physdev == ip2->physdev &&
306                (ip1->wildcard ?
307                 strncmp(ip1->iface, ip2->iface, strlen(ip1->iface)) == 0 :
308                 strcmp(ip1->iface, ip2->iface) == 0);
309 }
310 
311 static int
312 hash_netiface6_do_data_match(const struct hash_netiface6_elem *elem)
313 {
314         return elem->nomatch ? -ENOTEMPTY : 1;
315 }
316 
317 static void
318 hash_netiface6_data_set_flags(struct hash_netiface6_elem *elem, u32 flags)
319 {
320         elem->nomatch = (flags >> 16) & IPSET_FLAG_NOMATCH;
321 }
322 
323 static void
324 hash_netiface6_data_reset_flags(struct hash_netiface6_elem *elem, u8 *flags)
325 {
326         swap(*flags, elem->nomatch);
327 }
328 
329 static void
330 hash_netiface6_data_netmask(struct hash_netiface6_elem *elem, u8 cidr)
331 {
332         ip6_netmask(&elem->ip, cidr);
333         elem->cidr = cidr;
334 }
335 
336 static bool
337 hash_netiface6_data_list(struct sk_buff *skb,
338                          const struct hash_netiface6_elem *data)
339 {
340         u32 flags = (data->physdev ? IPSET_FLAG_PHYSDEV : 0) |
341                     (data->wildcard ? IPSET_FLAG_IFACE_WILDCARD : 0);
342 
343         if (data->nomatch)
344                 flags |= IPSET_FLAG_NOMATCH;
345         if (nla_put_ipaddr6(skb, IPSET_ATTR_IP, &data->ip.in6) ||
346             nla_put_u8(skb, IPSET_ATTR_CIDR, data->cidr) ||
347             nla_put_string(skb, IPSET_ATTR_IFACE, data->iface) ||
348             (flags &&
349              nla_put_net32(skb, IPSET_ATTR_CADT_FLAGS, htonl(flags))))
350                 goto nla_put_failure;
351         return false;
352 
353 nla_put_failure:
354         return true;
355 }
356 
357 static void
358 hash_netiface6_data_next(struct hash_netiface6_elem *next,
359                          const struct hash_netiface6_elem *d)
360 {
361 }
362 
363 #undef MTYPE
364 #undef HOST_MASK
365 
366 #define MTYPE           hash_netiface6
367 #define HOST_MASK       128
368 #define HKEY_DATALEN    sizeof(struct hash_netiface6_elem_hashed)
369 #define IP_SET_EMIT_CREATE
370 #include "ip_set_hash_gen.h"
371 
372 static int
373 hash_netiface6_kadt(struct ip_set *set, const struct sk_buff *skb,
374                     const struct xt_action_param *par,
375                     enum ipset_adt adt, struct ip_set_adt_opt *opt)
376 {
377         struct hash_netiface6 *h = set->data;
378         ipset_adtfn adtfn = set->variant->adt[adt];
379         struct hash_netiface6_elem e = {
380                 .cidr = INIT_CIDR(h->nets[0].cidr[0], HOST_MASK),
381                 .elem = 1,
382         };
383         struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
384 
385         if (adt == IPSET_TEST)
386                 e.cidr = HOST_MASK;
387 
388         ip6addrptr(skb, opt->flags & IPSET_DIM_ONE_SRC, &e.ip.in6);
389         ip6_netmask(&e.ip, e.cidr);
390 
391         if (opt->cmdflags & IPSET_FLAG_PHYSDEV) {
392 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
393                 const char *eiface = SRCDIR ? get_physindev_name(skb) :
394                                               get_physoutdev_name(skb);
395 
396                 if (!eiface)
397                         return -EINVAL;
398                 STRLCPY(e.iface, eiface);
399                 e.physdev = 1;
400 #endif
401         } else {
402                 STRLCPY(e.iface, SRCDIR ? IFACE(in) : IFACE(out));
403         }
404 
405         if (strlen(e.iface) == 0)
406                 return -EINVAL;
407 
408         return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
409 }
410 
411 static int
412 hash_netiface6_uadt(struct ip_set *set, struct nlattr *tb[],
413                     enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
414 {
415         ipset_adtfn adtfn = set->variant->adt[adt];
416         struct hash_netiface6_elem e = { .cidr = HOST_MASK, .elem = 1 };
417         struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
418         int ret;
419 
420         if (tb[IPSET_ATTR_LINENO])
421                 *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
422 
423         if (unlikely(!tb[IPSET_ATTR_IP] ||
424                      !tb[IPSET_ATTR_IFACE] ||
425                      !ip_set_optattr_netorder(tb, IPSET_ATTR_CADT_FLAGS)))
426                 return -IPSET_ERR_PROTOCOL;
427         if (unlikely(tb[IPSET_ATTR_IP_TO]))
428                 return -IPSET_ERR_HASH_RANGE_UNSUPPORTED;
429 
430         ret = ip_set_get_ipaddr6(tb[IPSET_ATTR_IP], &e.ip);
431         if (ret)
432                 return ret;
433 
434         ret = ip_set_get_extensions(set, tb, &ext);
435         if (ret)
436                 return ret;
437 
438         if (tb[IPSET_ATTR_CIDR]) {
439                 e.cidr = nla_get_u8(tb[IPSET_ATTR_CIDR]);
440                 if (e.cidr > HOST_MASK)
441                         return -IPSET_ERR_INVALID_CIDR;
442         }
443 
444         ip6_netmask(&e.ip, e.cidr);
445 
446         nla_strscpy(e.iface, tb[IPSET_ATTR_IFACE], IFNAMSIZ);
447 
448         if (tb[IPSET_ATTR_CADT_FLAGS]) {
449                 u32 cadt_flags = ip_set_get_h32(tb[IPSET_ATTR_CADT_FLAGS]);
450 
451                 if (cadt_flags & IPSET_FLAG_PHYSDEV)
452                         e.physdev = 1;
453                 if (cadt_flags & IPSET_FLAG_NOMATCH)
454                         flags |= (IPSET_FLAG_NOMATCH << 16);
455                 if (cadt_flags & IPSET_FLAG_IFACE_WILDCARD)
456                         e.wildcard = 1;
457         }
458 
459         ret = adtfn(set, &e, &ext, &ext, flags);
460 
461         return ip_set_enomatch(ret, flags, adt, set) ? -ret :
462                ip_set_eexist(ret, flags) ? 0 : ret;
463 }
464 
465 static struct ip_set_type hash_netiface_type __read_mostly = {
466         .name           = "hash:net,iface",
467         .protocol       = IPSET_PROTOCOL,
468         .features       = IPSET_TYPE_IP | IPSET_TYPE_IFACE |
469                           IPSET_TYPE_NOMATCH,
470         .dimension      = IPSET_DIM_TWO,
471         .family         = NFPROTO_UNSPEC,
472         .revision_min   = IPSET_TYPE_REV_MIN,
473         .revision_max   = IPSET_TYPE_REV_MAX,
474         .create_flags[IPSET_TYPE_REV_MAX] = IPSET_CREATE_FLAG_BUCKETSIZE,
475         .create         = hash_netiface_create,
476         .create_policy  = {
477                 [IPSET_ATTR_HASHSIZE]   = { .type = NLA_U32 },
478                 [IPSET_ATTR_MAXELEM]    = { .type = NLA_U32 },
479                 [IPSET_ATTR_INITVAL]    = { .type = NLA_U32 },
480                 [IPSET_ATTR_BUCKETSIZE] = { .type = NLA_U8 },
481                 [IPSET_ATTR_RESIZE]     = { .type = NLA_U8  },
482                 [IPSET_ATTR_PROTO]      = { .type = NLA_U8 },
483                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
484                 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
485         },
486         .adt_policy     = {
487                 [IPSET_ATTR_IP]         = { .type = NLA_NESTED },
488                 [IPSET_ATTR_IP_TO]      = { .type = NLA_NESTED },
489                 [IPSET_ATTR_IFACE]      = { .type = NLA_NUL_STRING,
490                                             .len  = IFNAMSIZ - 1 },
491                 [IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
492                 [IPSET_ATTR_CIDR]       = { .type = NLA_U8 },
493                 [IPSET_ATTR_TIMEOUT]    = { .type = NLA_U32 },
494                 [IPSET_ATTR_LINENO]     = { .type = NLA_U32 },
495                 [IPSET_ATTR_BYTES]      = { .type = NLA_U64 },
496                 [IPSET_ATTR_PACKETS]    = { .type = NLA_U64 },
497                 [IPSET_ATTR_COMMENT]    = { .type = NLA_NUL_STRING,
498                                             .len  = IPSET_MAX_COMMENT_SIZE },
499                 [IPSET_ATTR_SKBMARK]    = { .type = NLA_U64 },
500                 [IPSET_ATTR_SKBPRIO]    = { .type = NLA_U32 },
501                 [IPSET_ATTR_SKBQUEUE]   = { .type = NLA_U16 },
502         },
503         .me             = THIS_MODULE,
504 };
505 
506 static int __init
507 hash_netiface_init(void)
508 {
509         return ip_set_type_register(&hash_netiface_type);
510 }
511 
512 static void __exit
513 hash_netiface_fini(void)
514 {
515         rcu_barrier();
516         ip_set_type_unregister(&hash_netiface_type);
517 }
518 
519 module_init(hash_netiface_init);
520 module_exit(hash_netiface_fini);
521 

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