libnftnl  1.3.2
object.c
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * (C) 2012-2016 by Pablo Neira Ayuso <pablo@netfilter.org>
4  */
5 #include "internal.h"
6 
7 #include <time.h>
8 #include <endian.h>
9 #include <stdint.h>
10 #include <limits.h>
11 #include <stdlib.h>
12 #include <string.h>
13 #include <netinet/in.h>
14 #include <errno.h>
15 
16 #include <libmnl/libmnl.h>
17 #include <linux/netfilter/nfnetlink.h>
18 #include <linux/netfilter/nf_tables.h>
19 
20 #include <libnftnl/object.h>
21 #include "obj.h"
22 
23 static struct obj_ops *obj_ops[__NFT_OBJECT_MAX] = {
24  [NFT_OBJECT_COUNTER] = &obj_ops_counter,
25  [NFT_OBJECT_QUOTA] = &obj_ops_quota,
26  [NFT_OBJECT_CT_HELPER] = &obj_ops_ct_helper,
27  [NFT_OBJECT_LIMIT] = &obj_ops_limit,
28  [NFT_OBJECT_TUNNEL] = &obj_ops_tunnel,
29  [NFT_OBJECT_CT_TIMEOUT] = &obj_ops_ct_timeout,
30  [NFT_OBJECT_SECMARK] = &obj_ops_secmark,
31  [NFT_OBJECT_CT_EXPECT] = &obj_ops_ct_expect,
32  [NFT_OBJECT_SYNPROXY] = &obj_ops_synproxy,
33  [NFT_OBJECT_CONNLIMIT] = &obj_ops_connlimit,
34 };
35 
36 static struct obj_ops *nftnl_obj_ops_lookup(uint32_t type)
37 {
38  if (type > NFT_OBJECT_MAX)
39  return NULL;
40 
41  return obj_ops[type];
42 }
43 
44 EXPORT_SYMBOL(nftnl_obj_alloc);
45 struct nftnl_obj *nftnl_obj_alloc(void)
46 {
47  return calloc(1, sizeof(struct nftnl_obj));
48 }
49 
50 EXPORT_SYMBOL(nftnl_obj_free);
51 void nftnl_obj_free(const struct nftnl_obj *obj)
52 {
53  if (obj->flags & (1 << NFTNL_OBJ_TABLE))
54  xfree(obj->table);
55  if (obj->flags & (1 << NFTNL_OBJ_NAME))
56  xfree(obj->name);
57  if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
58  xfree(obj->user.data);
59  if (obj->flags & (1 << NFTNL_OBJ_TUNNEL_OPTS)) {
60  nftnl_tunnel_opts_free(obj->data.tunnel.tun_opts);
61  xfree(obj->data.tunnel.tun_opts);
62  }
63 
64  xfree(obj);
65 }
66 
67 EXPORT_SYMBOL(nftnl_obj_is_set);
68 bool nftnl_obj_is_set(const struct nftnl_obj *obj, uint16_t attr)
69 {
70  return obj->flags & (1 << attr);
71 }
72 
73 EXPORT_SYMBOL(nftnl_obj_unset);
74 void nftnl_obj_unset(struct nftnl_obj *obj, uint16_t attr)
75 {
76  if (!(obj->flags & (1 << attr)))
77  return;
78 
79  switch (attr) {
80  case NFTNL_OBJ_TABLE:
81  xfree(obj->table);
82  break;
83  case NFTNL_OBJ_NAME:
84  xfree(obj->name);
85  break;
86  case NFTNL_OBJ_USERDATA:
87  xfree(obj->user.data);
88  break;
89  case NFTNL_OBJ_TYPE:
90  case NFTNL_OBJ_FAMILY:
91  case NFTNL_OBJ_USE:
92  case NFTNL_OBJ_HANDLE:
93  break;
94  default:
95  break;
96  }
97 
98  obj->flags &= ~(1 << attr);
99 }
100 
101 static uint32_t nftnl_obj_validate[NFTNL_OBJ_MAX + 1] = {
102  [NFTNL_OBJ_TYPE] = sizeof(uint32_t),
103  [NFTNL_OBJ_FAMILY] = sizeof(uint32_t),
104  [NFTNL_OBJ_USE] = sizeof(uint32_t),
105  [NFTNL_OBJ_HANDLE] = sizeof(uint64_t),
106 };
107 
108 EXPORT_SYMBOL(nftnl_obj_set_data);
109 int nftnl_obj_set_data(struct nftnl_obj *obj, uint16_t attr,
110  const void *data, uint32_t data_len)
111 {
112  if (attr < NFTNL_OBJ_MAX)
113  nftnl_assert_validate(data, nftnl_obj_validate, attr, data_len);
114 
115  switch (attr) {
116  case NFTNL_OBJ_TABLE:
117  return nftnl_set_str_attr(&obj->table, &obj->flags,
118  attr, data, data_len);
119  break;
120  case NFTNL_OBJ_NAME:
121  return nftnl_set_str_attr(&obj->name, &obj->flags,
122  attr, data, data_len);
123  case NFTNL_OBJ_TYPE:
124  obj->ops = nftnl_obj_ops_lookup(*((uint32_t *)data));
125  if (!obj->ops)
126  return -1;
127  break;
128  case NFTNL_OBJ_FAMILY:
129  memcpy(&obj->family, data, sizeof(obj->family));
130  break;
131  case NFTNL_OBJ_USE:
132  memcpy(&obj->use, data, sizeof(obj->use));
133  break;
134  case NFTNL_OBJ_HANDLE:
135  memcpy(&obj->handle, data, sizeof(obj->handle));
136  break;
137  case NFTNL_OBJ_USERDATA:
138  if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
139  xfree(obj->user.data);
140 
141  obj->user.data = malloc(data_len);
142  if (!obj->user.data)
143  return -1;
144  memcpy(obj->user.data, data, data_len);
145  obj->user.len = data_len;
146  break;
147  default:
148  if (!obj->ops ||
149  attr < NFTNL_OBJ_BASE ||
150  attr > obj->ops->nftnl_max_attr ||
151  !obj->ops->attr_policy)
152  return -1;
153 
154  if (obj->ops->attr_policy[attr].maxlen &&
155  obj->ops->attr_policy[attr].maxlen < data_len)
156  return -1;
157 
158  if (obj->ops->set(obj, attr, data, data_len) < 0)
159  return -1;
160  }
161  obj->flags |= (1 << attr);
162  return 0;
163 }
164 
165 void nftnl_obj_set(struct nftnl_obj *obj, uint16_t attr, const void *data) __visible;
166 void nftnl_obj_set(struct nftnl_obj *obj, uint16_t attr, const void *data)
167 {
168  nftnl_obj_set_data(obj, attr, data, nftnl_obj_validate[attr]);
169 }
170 
171 EXPORT_SYMBOL(nftnl_obj_set_u8);
172 int nftnl_obj_set_u8(struct nftnl_obj *obj, uint16_t attr, uint8_t val)
173 {
174  return nftnl_obj_set_data(obj, attr, &val, sizeof(uint8_t));
175 }
176 
177 EXPORT_SYMBOL(nftnl_obj_set_u16);
178 int nftnl_obj_set_u16(struct nftnl_obj *obj, uint16_t attr, uint16_t val)
179 {
180  return nftnl_obj_set_data(obj, attr, &val, sizeof(uint16_t));
181 }
182 
183 EXPORT_SYMBOL(nftnl_obj_set_u32);
184 int nftnl_obj_set_u32(struct nftnl_obj *obj, uint16_t attr, uint32_t val)
185 {
186  return nftnl_obj_set_data(obj, attr, &val, sizeof(uint32_t));
187 }
188 
189 EXPORT_SYMBOL(nftnl_obj_set_u64);
190 int nftnl_obj_set_u64(struct nftnl_obj *obj, uint16_t attr, uint64_t val)
191 {
192  return nftnl_obj_set_data(obj, attr, &val, sizeof(uint64_t));
193 }
194 
195 EXPORT_SYMBOL(nftnl_obj_set_str);
196 int nftnl_obj_set_str(struct nftnl_obj *obj, uint16_t attr, const char *str)
197 {
198  return nftnl_obj_set_data(obj, attr, str, strlen(str) + 1);
199 }
200 
201 EXPORT_SYMBOL(nftnl_obj_get_data);
202 const void *nftnl_obj_get_data(const struct nftnl_obj *obj, uint16_t attr,
203  uint32_t *data_len)
204 {
205  if (!(obj->flags & (1 << attr)))
206  return NULL;
207 
208  switch(attr) {
209  case NFTNL_OBJ_TABLE:
210  return obj->table;
211  case NFTNL_OBJ_NAME:
212  return obj->name;
213  case NFTNL_OBJ_TYPE:
214  if (!obj->ops)
215  return NULL;
216 
217  *data_len = sizeof(uint32_t);
218  return &obj->ops->type;
219  case NFTNL_OBJ_FAMILY:
220  *data_len = sizeof(uint32_t);
221  return &obj->family;
222  case NFTNL_OBJ_USE:
223  *data_len = sizeof(uint32_t);
224  return &obj->use;
225  case NFTNL_OBJ_HANDLE:
226  *data_len = sizeof(uint64_t);
227  return &obj->handle;
228  case NFTNL_OBJ_USERDATA:
229  *data_len = obj->user.len;
230  return obj->user.data;
231  default:
232  if (obj->ops)
233  return obj->ops->get(obj, attr, data_len);
234  break;
235  }
236  return NULL;
237 }
238 
239 EXPORT_SYMBOL(nftnl_obj_get);
240 const void *nftnl_obj_get(const struct nftnl_obj *obj, uint16_t attr)
241 {
242  uint32_t data_len;
243  return nftnl_obj_get_data(obj, attr, &data_len);
244 }
245 
246 EXPORT_SYMBOL(nftnl_obj_get_u8);
247 uint8_t nftnl_obj_get_u8(const struct nftnl_obj *obj, uint16_t attr)
248 {
249  const void *ret = nftnl_obj_get(obj, attr);
250  return ret == NULL ? 0 : *((uint8_t *)ret);
251 }
252 
253 EXPORT_SYMBOL(nftnl_obj_get_u16);
254 uint16_t nftnl_obj_get_u16(const struct nftnl_obj *obj, uint16_t attr)
255 {
256  const void *ret = nftnl_obj_get(obj, attr);
257  return ret == NULL ? 0 : *((uint16_t *)ret);
258 }
259 
260 EXPORT_SYMBOL(nftnl_obj_get_u32);
261 uint32_t nftnl_obj_get_u32(const struct nftnl_obj *obj, uint16_t attr)
262 {
263  const void *ret = nftnl_obj_get(obj, attr);
264  return ret == NULL ? 0 : *((uint32_t *)ret);
265 }
266 
267 EXPORT_SYMBOL(nftnl_obj_get_u64);
268 uint64_t nftnl_obj_get_u64(const struct nftnl_obj *obj, uint16_t attr)
269 {
270  const void *ret = nftnl_obj_get(obj, attr);
271  return ret == NULL ? 0 : *((uint64_t *)ret);
272 }
273 
274 EXPORT_SYMBOL(nftnl_obj_get_str);
275 const char *nftnl_obj_get_str(const struct nftnl_obj *obj, uint16_t attr)
276 {
277  return nftnl_obj_get(obj, attr);
278 }
279 
280 EXPORT_SYMBOL(nftnl_obj_nlmsg_build_payload);
281 void nftnl_obj_nlmsg_build_payload(struct nlmsghdr *nlh,
282  const struct nftnl_obj *obj)
283 {
284  if (obj->flags & (1 << NFTNL_OBJ_TABLE))
285  mnl_attr_put_strz(nlh, NFTA_OBJ_TABLE, obj->table);
286  if (obj->flags & (1 << NFTNL_OBJ_NAME))
287  mnl_attr_put_strz(nlh, NFTA_OBJ_NAME, obj->name);
288  if (obj->flags & (1 << NFTNL_OBJ_TYPE))
289  mnl_attr_put_u32(nlh, NFTA_OBJ_TYPE, htonl(obj->ops->type));
290  if (obj->flags & (1 << NFTNL_OBJ_HANDLE))
291  mnl_attr_put_u64(nlh, NFTA_OBJ_HANDLE, htobe64(obj->handle));
292  if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
293  mnl_attr_put(nlh, NFTA_OBJ_USERDATA, obj->user.len, obj->user.data);
294  if (obj->ops) {
295  struct nlattr *nest = mnl_attr_nest_start(nlh, NFTA_OBJ_DATA);
296 
297  obj->ops->build(nlh, obj);
298  mnl_attr_nest_end(nlh, nest);
299  }
300 }
301 
302 static int nftnl_obj_parse_attr_cb(const struct nlattr *attr, void *data)
303 {
304  const struct nlattr **tb = data;
305  int type = mnl_attr_get_type(attr);
306 
307  if (mnl_attr_type_valid(attr, NFTA_OBJ_MAX) < 0)
308  return MNL_CB_OK;
309 
310  switch(type) {
311  case NFTA_OBJ_TABLE:
312  case NFTA_OBJ_NAME:
313  if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
314  abi_breakage();
315  break;
316  case NFTA_OBJ_HANDLE:
317  if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
318  abi_breakage();
319  break;
320  case NFTA_OBJ_DATA:
321  if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0)
322  abi_breakage();
323  break;
324  case NFTA_OBJ_USE:
325  if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
326  abi_breakage();
327  break;
328  case NFTA_OBJ_USERDATA:
329  if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0)
330  abi_breakage();
331  break;
332  }
333 
334  tb[type] = attr;
335  return MNL_CB_OK;
336 }
337 
338 EXPORT_SYMBOL(nftnl_obj_nlmsg_parse);
339 int nftnl_obj_nlmsg_parse(const struct nlmsghdr *nlh, struct nftnl_obj *obj)
340 {
341  struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh);
342  struct nlattr *tb[NFTA_OBJ_MAX + 1] = {};
343  int err;
344 
345  if (mnl_attr_parse(nlh, sizeof(*nfg), nftnl_obj_parse_attr_cb, tb) < 0)
346  return -1;
347 
348  if (nftnl_parse_str_attr(tb[NFTA_OBJ_TABLE], NFTNL_OBJ_TABLE,
349  &obj->table, &obj->flags) < 0)
350  return -1;
351  if (nftnl_parse_str_attr(tb[NFTA_OBJ_NAME], NFTNL_OBJ_NAME,
352  &obj->name, &obj->flags) < 0)
353  return -1;
354  if (tb[NFTA_OBJ_TYPE]) {
355  uint32_t type = ntohl(mnl_attr_get_u32(tb[NFTA_OBJ_TYPE]));
356 
357  obj->ops = nftnl_obj_ops_lookup(type);
358  if (obj->ops)
359  obj->flags |= (1 << NFTNL_OBJ_TYPE);
360  }
361  if (tb[NFTA_OBJ_DATA]) {
362  if (obj->ops) {
363  err = obj->ops->parse(obj, tb[NFTA_OBJ_DATA]);
364  if (err < 0)
365  return err;
366  }
367  }
368  if (tb[NFTA_OBJ_USE]) {
369  obj->use = ntohl(mnl_attr_get_u32(tb[NFTA_OBJ_USE]));
370  obj->flags |= (1 << NFTNL_OBJ_USE);
371  }
372  if (tb[NFTA_OBJ_HANDLE]) {
373  obj->handle = be64toh(mnl_attr_get_u64(tb[NFTA_OBJ_HANDLE]));
374  obj->flags |= (1 << NFTNL_OBJ_HANDLE);
375  }
376  if (tb[NFTA_OBJ_USERDATA]) {
377  nftnl_obj_set_data(obj, NFTNL_OBJ_USERDATA,
378  mnl_attr_get_payload(tb[NFTA_OBJ_USERDATA]),
379  mnl_attr_get_payload_len(tb[NFTA_OBJ_USERDATA]));
380  }
381 
382  obj->family = nfg->nfgen_family;
383  obj->flags |= (1 << NFTNL_OBJ_FAMILY);
384 
385  return 0;
386 }
387 
388 EXPORT_SYMBOL(nftnl_obj_parse);
389 int nftnl_obj_parse(struct nftnl_obj *obj, enum nftnl_parse_type type,
390  const char *data, struct nftnl_parse_err *err)
391 {
392  errno = EOPNOTSUPP;
393 
394  return -1;
395 }
396 
397 EXPORT_SYMBOL(nftnl_obj_parse_file);
398 int nftnl_obj_parse_file(struct nftnl_obj *obj, enum nftnl_parse_type type,
399  FILE *fp, struct nftnl_parse_err *err)
400 {
401  errno = EOPNOTSUPP;
402 
403  return -1;
404 }
405 
406 static int nftnl_obj_snprintf_dflt(char *buf, size_t remain,
407  const struct nftnl_obj *obj,
408  uint32_t type, uint32_t flags)
409 {
410  const char *name = obj->ops ? obj->ops->name : "(unknown)";
411  int ret, offset = 0;
412 
413  ret = snprintf(buf, remain, "table %s name %s use %u [ %s ",
414  obj->table, obj->name, obj->use, name);
415  SNPRINTF_BUFFER_SIZE(ret, remain, offset);
416 
417  if (obj->ops) {
418  ret = obj->ops->output(buf + offset, remain, flags, obj);
419  SNPRINTF_BUFFER_SIZE(ret, remain, offset);
420  }
421  ret = snprintf(buf + offset, remain, "]");
422  SNPRINTF_BUFFER_SIZE(ret, remain, offset);
423 
424  return offset;
425 }
426 
427 static int nftnl_obj_cmd_snprintf(char *buf, size_t remain,
428  const struct nftnl_obj *obj, uint32_t cmd,
429  uint32_t type, uint32_t flags)
430 {
431  int ret, offset = 0;
432 
433  if (type != NFTNL_OUTPUT_DEFAULT)
434  return -1;
435 
436  ret = nftnl_obj_snprintf_dflt(buf + offset, remain, obj, type, flags);
437  SNPRINTF_BUFFER_SIZE(ret, remain, offset);
438  return offset;
439 }
440 
441 EXPORT_SYMBOL(nftnl_obj_snprintf);
442 int nftnl_obj_snprintf(char *buf, size_t size, const struct nftnl_obj *obj,
443  uint32_t type, uint32_t flags)
444 {
445  if (size)
446  buf[0] = '\0';
447 
448  return nftnl_obj_cmd_snprintf(buf, size, obj, nftnl_flag2cmd(flags),
449  type, flags);
450 }
451 
452 static int nftnl_obj_do_snprintf(char *buf, size_t size, const void *obj,
453  uint32_t cmd, uint32_t type, uint32_t flags)
454 {
455  return nftnl_obj_snprintf(buf, size, obj, type, flags);
456 }
457 
458 EXPORT_SYMBOL(nftnl_obj_fprintf);
459 int nftnl_obj_fprintf(FILE *fp, const struct nftnl_obj *obj, uint32_t type,
460  uint32_t flags)
461 {
462  return nftnl_fprintf(fp, obj, NFTNL_CMD_UNSPEC, type, flags,
463  nftnl_obj_do_snprintf);
464 }
465 
466 struct nftnl_obj_list {
467  struct list_head list;
468 };
469 
470 EXPORT_SYMBOL(nftnl_obj_list_alloc);
471 struct nftnl_obj_list *nftnl_obj_list_alloc(void)
472 {
473  struct nftnl_obj_list *list;
474 
475  list = calloc(1, sizeof(struct nftnl_obj_list));
476  if (list == NULL)
477  return NULL;
478 
479  INIT_LIST_HEAD(&list->list);
480 
481  return list;
482 }
483 
484 EXPORT_SYMBOL(nftnl_obj_list_free);
485 void nftnl_obj_list_free(struct nftnl_obj_list *list)
486 {
487  struct nftnl_obj *r, *tmp;
488 
489  list_for_each_entry_safe(r, tmp, &list->list, head) {
490  list_del(&r->head);
491  nftnl_obj_free(r);
492  }
493  xfree(list);
494 }
495 
496 EXPORT_SYMBOL(nftnl_obj_list_is_empty);
497 int nftnl_obj_list_is_empty(struct nftnl_obj_list *list)
498 {
499  return list_empty(&list->list);
500 }
501 
502 EXPORT_SYMBOL(nftnl_obj_list_add);
503 void nftnl_obj_list_add(struct nftnl_obj *r, struct nftnl_obj_list *list)
504 {
505  list_add(&r->head, &list->list);
506 }
507 
508 EXPORT_SYMBOL(nftnl_obj_list_add_tail);
509 void nftnl_obj_list_add_tail(struct nftnl_obj *r,
510  struct nftnl_obj_list *list)
511 {
512  list_add_tail(&r->head, &list->list);
513 }
514 
515 EXPORT_SYMBOL(nftnl_obj_list_del);
516 void nftnl_obj_list_del(struct nftnl_obj *t)
517 {
518  list_del(&t->head);
519 }
520 
521 EXPORT_SYMBOL(nftnl_obj_list_foreach);
522 int nftnl_obj_list_foreach(struct nftnl_obj_list *table_list,
523  int (*cb)(struct nftnl_obj *t, void *data),
524  void *data)
525 {
526  struct nftnl_obj *cur, *tmp;
527  int ret;
528 
529  list_for_each_entry_safe(cur, tmp, &table_list->list, head) {
530  ret = cb(cur, data);
531  if (ret < 0)
532  return ret;
533  }
534  return 0;
535 }
536 
537 struct nftnl_obj_list_iter {
538  struct nftnl_obj_list *list;
539  struct nftnl_obj *cur;
540 };
541 
542 EXPORT_SYMBOL(nftnl_obj_list_iter_create);
543 struct nftnl_obj_list_iter *
544 nftnl_obj_list_iter_create(struct nftnl_obj_list *l)
545 {
546  struct nftnl_obj_list_iter *iter;
547 
548  iter = calloc(1, sizeof(struct nftnl_obj_list_iter));
549  if (iter == NULL)
550  return NULL;
551 
552  iter->list = l;
553  if (nftnl_obj_list_is_empty(l))
554  iter->cur = NULL;
555  else
556  iter->cur = list_entry(l->list.next, struct nftnl_obj, head);
557 
558  return iter;
559 }
560 
561 EXPORT_SYMBOL(nftnl_obj_list_iter_next);
562 struct nftnl_obj *nftnl_obj_list_iter_next(struct nftnl_obj_list_iter *iter)
563 {
564  struct nftnl_obj *r = iter->cur;
565 
566  if (r == NULL)
567  return NULL;
568 
569  /* get next table, if any */
570  iter->cur = list_entry(iter->cur->head.next, struct nftnl_obj, head);
571  if (&iter->cur->head == iter->list->list.next)
572  return NULL;
573 
574  return r;
575 }
576 
577 EXPORT_SYMBOL(nftnl_obj_list_iter_destroy);
578 void nftnl_obj_list_iter_destroy(struct nftnl_obj_list_iter *iter)
579 {
580  xfree(iter);
581 }
nftnl_obj_list_iter
Definition: object.c:537
nftnl_obj_list
Definition: object.c:466
Generated by   doxygen 1.8.10