libnftnl 1.2.9
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
23static 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};
34
35static struct obj_ops *nftnl_obj_ops_lookup(uint32_t type)
36{
37 if (type > NFT_OBJECT_MAX)
38 return NULL;
39
40 return obj_ops[type];
41}
42
43EXPORT_SYMBOL(nftnl_obj_alloc);
44struct nftnl_obj *nftnl_obj_alloc(void)
45{
46 return calloc(1, sizeof(struct nftnl_obj));
47}
48
49EXPORT_SYMBOL(nftnl_obj_free);
50void nftnl_obj_free(const struct nftnl_obj *obj)
51{
52 if (obj->flags & (1 << NFTNL_OBJ_TABLE))
53 xfree(obj->table);
54 if (obj->flags & (1 << NFTNL_OBJ_NAME))
55 xfree(obj->name);
56 if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
57 xfree(obj->user.data);
58
59 xfree(obj);
60}
61
62EXPORT_SYMBOL(nftnl_obj_is_set);
63bool nftnl_obj_is_set(const struct nftnl_obj *obj, uint16_t attr)
64{
65 return obj->flags & (1 << attr);
66}
67
68EXPORT_SYMBOL(nftnl_obj_unset);
69void nftnl_obj_unset(struct nftnl_obj *obj, uint16_t attr)
70{
71 if (!(obj->flags & (1 << attr)))
72 return;
73
74 switch (attr) {
75 case NFTNL_OBJ_TABLE:
76 xfree(obj->table);
77 break;
78 case NFTNL_OBJ_NAME:
79 xfree(obj->name);
80 break;
81 case NFTNL_OBJ_USERDATA:
82 xfree(obj->user.data);
83 break;
84 case NFTNL_OBJ_TYPE:
85 case NFTNL_OBJ_FAMILY:
86 case NFTNL_OBJ_USE:
87 case NFTNL_OBJ_HANDLE:
88 break;
89 default:
90 break;
91 }
92
93 obj->flags &= ~(1 << attr);
94}
95
96static uint32_t nftnl_obj_validate[NFTNL_OBJ_MAX + 1] = {
97 [NFTNL_OBJ_TYPE] = sizeof(uint32_t),
98 [NFTNL_OBJ_FAMILY] = sizeof(uint32_t),
99 [NFTNL_OBJ_USE] = sizeof(uint32_t),
100 [NFTNL_OBJ_HANDLE] = sizeof(uint64_t),
101};
102
103EXPORT_SYMBOL(nftnl_obj_set_data);
104int nftnl_obj_set_data(struct nftnl_obj *obj, uint16_t attr,
105 const void *data, uint32_t data_len)
106{
107 if (attr < NFTNL_OBJ_MAX)
108 nftnl_assert_validate(data, nftnl_obj_validate, attr, data_len);
109
110 switch (attr) {
111 case NFTNL_OBJ_TABLE:
112 return nftnl_set_str_attr(&obj->table, &obj->flags,
113 attr, data, data_len);
114 break;
115 case NFTNL_OBJ_NAME:
116 return nftnl_set_str_attr(&obj->name, &obj->flags,
117 attr, data, data_len);
118 case NFTNL_OBJ_TYPE:
119 obj->ops = nftnl_obj_ops_lookup(*((uint32_t *)data));
120 if (!obj->ops)
121 return -1;
122 break;
123 case NFTNL_OBJ_FAMILY:
124 memcpy(&obj->family, data, sizeof(obj->family));
125 break;
126 case NFTNL_OBJ_USE:
127 memcpy(&obj->use, data, sizeof(obj->use));
128 break;
129 case NFTNL_OBJ_HANDLE:
130 memcpy(&obj->handle, data, sizeof(obj->handle));
131 break;
132 case NFTNL_OBJ_USERDATA:
133 if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
134 xfree(obj->user.data);
135
136 obj->user.data = malloc(data_len);
137 if (!obj->user.data)
138 return -1;
139 memcpy(obj->user.data, data, data_len);
140 obj->user.len = data_len;
141 break;
142 default:
143 if (!obj->ops ||
144 attr < NFTNL_OBJ_BASE ||
145 attr > obj->ops->nftnl_max_attr ||
146 !obj->ops->attr_policy)
147 return -1;
148
149 if (obj->ops->attr_policy[attr].maxlen &&
150 obj->ops->attr_policy[attr].maxlen < data_len)
151 return -1;
152
153 if (obj->ops->set(obj, attr, data, data_len) < 0)
154 return -1;
155 }
156 obj->flags |= (1 << attr);
157 return 0;
158}
159
160void nftnl_obj_set(struct nftnl_obj *obj, uint16_t attr, const void *data) __visible;
161void nftnl_obj_set(struct nftnl_obj *obj, uint16_t attr, const void *data)
162{
163 nftnl_obj_set_data(obj, attr, data, nftnl_obj_validate[attr]);
164}
165
166EXPORT_SYMBOL(nftnl_obj_set_u8);
167int nftnl_obj_set_u8(struct nftnl_obj *obj, uint16_t attr, uint8_t val)
168{
169 return nftnl_obj_set_data(obj, attr, &val, sizeof(uint8_t));
170}
171
172EXPORT_SYMBOL(nftnl_obj_set_u16);
173int nftnl_obj_set_u16(struct nftnl_obj *obj, uint16_t attr, uint16_t val)
174{
175 return nftnl_obj_set_data(obj, attr, &val, sizeof(uint16_t));
176}
177
178EXPORT_SYMBOL(nftnl_obj_set_u32);
179int nftnl_obj_set_u32(struct nftnl_obj *obj, uint16_t attr, uint32_t val)
180{
181 return nftnl_obj_set_data(obj, attr, &val, sizeof(uint32_t));
182}
183
184EXPORT_SYMBOL(nftnl_obj_set_u64);
185int nftnl_obj_set_u64(struct nftnl_obj *obj, uint16_t attr, uint64_t val)
186{
187 return nftnl_obj_set_data(obj, attr, &val, sizeof(uint64_t));
188}
189
190EXPORT_SYMBOL(nftnl_obj_set_str);
191int nftnl_obj_set_str(struct nftnl_obj *obj, uint16_t attr, const char *str)
192{
193 return nftnl_obj_set_data(obj, attr, str, strlen(str) + 1);
194}
195
196EXPORT_SYMBOL(nftnl_obj_get_data);
197const void *nftnl_obj_get_data(const struct nftnl_obj *obj, uint16_t attr,
198 uint32_t *data_len)
199{
200 if (!(obj->flags & (1 << attr)))
201 return NULL;
202
203 switch(attr) {
204 case NFTNL_OBJ_TABLE:
205 return obj->table;
206 case NFTNL_OBJ_NAME:
207 return obj->name;
208 case NFTNL_OBJ_TYPE:
209 if (!obj->ops)
210 return NULL;
211
212 *data_len = sizeof(uint32_t);
213 return &obj->ops->type;
214 case NFTNL_OBJ_FAMILY:
215 *data_len = sizeof(uint32_t);
216 return &obj->family;
217 case NFTNL_OBJ_USE:
218 *data_len = sizeof(uint32_t);
219 return &obj->use;
220 case NFTNL_OBJ_HANDLE:
221 *data_len = sizeof(uint64_t);
222 return &obj->handle;
223 case NFTNL_OBJ_USERDATA:
224 *data_len = obj->user.len;
225 return obj->user.data;
226 default:
227 if (obj->ops)
228 return obj->ops->get(obj, attr, data_len);
229 break;
230 }
231 return NULL;
232}
233
234EXPORT_SYMBOL(nftnl_obj_get);
235const void *nftnl_obj_get(const struct nftnl_obj *obj, uint16_t attr)
236{
237 uint32_t data_len;
238 return nftnl_obj_get_data(obj, attr, &data_len);
239}
240
241EXPORT_SYMBOL(nftnl_obj_get_u8);
242uint8_t nftnl_obj_get_u8(const struct nftnl_obj *obj, uint16_t attr)
243{
244 const void *ret = nftnl_obj_get(obj, attr);
245 return ret == NULL ? 0 : *((uint8_t *)ret);
246}
247
248EXPORT_SYMBOL(nftnl_obj_get_u16);
249uint16_t nftnl_obj_get_u16(const struct nftnl_obj *obj, uint16_t attr)
250{
251 const void *ret = nftnl_obj_get(obj, attr);
252 return ret == NULL ? 0 : *((uint16_t *)ret);
253}
254
255EXPORT_SYMBOL(nftnl_obj_get_u32);
256uint32_t nftnl_obj_get_u32(const struct nftnl_obj *obj, uint16_t attr)
257{
258 const void *ret = nftnl_obj_get(obj, attr);
259 return ret == NULL ? 0 : *((uint32_t *)ret);
260}
261
262EXPORT_SYMBOL(nftnl_obj_get_u64);
263uint64_t nftnl_obj_get_u64(const struct nftnl_obj *obj, uint16_t attr)
264{
265 const void *ret = nftnl_obj_get(obj, attr);
266 return ret == NULL ? 0 : *((uint64_t *)ret);
267}
268
269EXPORT_SYMBOL(nftnl_obj_get_str);
270const char *nftnl_obj_get_str(const struct nftnl_obj *obj, uint16_t attr)
271{
272 return nftnl_obj_get(obj, attr);
273}
274
275EXPORT_SYMBOL(nftnl_obj_nlmsg_build_payload);
276void nftnl_obj_nlmsg_build_payload(struct nlmsghdr *nlh,
277 const struct nftnl_obj *obj)
278{
279 if (obj->flags & (1 << NFTNL_OBJ_TABLE))
280 mnl_attr_put_strz(nlh, NFTA_OBJ_TABLE, obj->table);
281 if (obj->flags & (1 << NFTNL_OBJ_NAME))
282 mnl_attr_put_strz(nlh, NFTA_OBJ_NAME, obj->name);
283 if (obj->flags & (1 << NFTNL_OBJ_TYPE))
284 mnl_attr_put_u32(nlh, NFTA_OBJ_TYPE, htonl(obj->ops->type));
285 if (obj->flags & (1 << NFTNL_OBJ_HANDLE))
286 mnl_attr_put_u64(nlh, NFTA_OBJ_HANDLE, htobe64(obj->handle));
287 if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
288 mnl_attr_put(nlh, NFTA_OBJ_USERDATA, obj->user.len, obj->user.data);
289 if (obj->ops) {
290 struct nlattr *nest = mnl_attr_nest_start(nlh, NFTA_OBJ_DATA);
291
292 obj->ops->build(nlh, obj);
293 mnl_attr_nest_end(nlh, nest);
294 }
295}
296
297static int nftnl_obj_parse_attr_cb(const struct nlattr *attr, void *data)
298{
299 const struct nlattr **tb = data;
300 int type = mnl_attr_get_type(attr);
301
302 if (mnl_attr_type_valid(attr, NFTA_OBJ_MAX) < 0)
303 return MNL_CB_OK;
304
305 switch(type) {
306 case NFTA_OBJ_TABLE:
307 case NFTA_OBJ_NAME:
308 if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
309 abi_breakage();
310 break;
311 case NFTA_OBJ_HANDLE:
312 if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
313 abi_breakage();
314 break;
315 case NFTA_OBJ_DATA:
316 if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0)
317 abi_breakage();
318 break;
319 case NFTA_OBJ_USE:
320 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
321 abi_breakage();
322 break;
323 case NFTA_OBJ_USERDATA:
324 if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0)
325 abi_breakage();
326 break;
327 }
328
329 tb[type] = attr;
330 return MNL_CB_OK;
331}
332
333EXPORT_SYMBOL(nftnl_obj_nlmsg_parse);
334int nftnl_obj_nlmsg_parse(const struct nlmsghdr *nlh, struct nftnl_obj *obj)
335{
336 struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh);
337 struct nlattr *tb[NFTA_OBJ_MAX + 1] = {};
338 int err;
339
340 if (mnl_attr_parse(nlh, sizeof(*nfg), nftnl_obj_parse_attr_cb, tb) < 0)
341 return -1;
342
343 if (tb[NFTA_OBJ_TABLE]) {
344 obj->table = strdup(mnl_attr_get_str(tb[NFTA_OBJ_TABLE]));
345 obj->flags |= (1 << NFTNL_OBJ_TABLE);
346 }
347 if (tb[NFTA_OBJ_NAME]) {
348 obj->name = strdup(mnl_attr_get_str(tb[NFTA_OBJ_NAME]));
349 obj->flags |= (1 << NFTNL_OBJ_NAME);
350 }
351 if (tb[NFTA_OBJ_TYPE]) {
352 uint32_t type = ntohl(mnl_attr_get_u32(tb[NFTA_OBJ_TYPE]));
353
354 obj->ops = nftnl_obj_ops_lookup(type);
355 if (obj->ops)
356 obj->flags |= (1 << NFTNL_OBJ_TYPE);
357 }
358 if (tb[NFTA_OBJ_DATA]) {
359 if (obj->ops) {
360 err = obj->ops->parse(obj, tb[NFTA_OBJ_DATA]);
361 if (err < 0)
362 return err;
363 }
364 }
365 if (tb[NFTA_OBJ_USE]) {
366 obj->use = ntohl(mnl_attr_get_u32(tb[NFTA_OBJ_USE]));
367 obj->flags |= (1 << NFTNL_OBJ_USE);
368 }
369 if (tb[NFTA_OBJ_HANDLE]) {
370 obj->handle = be64toh(mnl_attr_get_u64(tb[NFTA_OBJ_HANDLE]));
371 obj->flags |= (1 << NFTNL_OBJ_HANDLE);
372 }
373 if (tb[NFTA_OBJ_USERDATA]) {
374 nftnl_obj_set_data(obj, NFTNL_OBJ_USERDATA,
375 mnl_attr_get_payload(tb[NFTA_OBJ_USERDATA]),
376 mnl_attr_get_payload_len(tb[NFTA_OBJ_USERDATA]));
377 }
378
379 obj->family = nfg->nfgen_family;
380 obj->flags |= (1 << NFTNL_OBJ_FAMILY);
381
382 return 0;
383}
384
385EXPORT_SYMBOL(nftnl_obj_parse);
386int nftnl_obj_parse(struct nftnl_obj *obj, enum nftnl_parse_type type,
387 const char *data, struct nftnl_parse_err *err)
388{
389 errno = EOPNOTSUPP;
390
391 return -1;
392}
393
394EXPORT_SYMBOL(nftnl_obj_parse_file);
395int nftnl_obj_parse_file(struct nftnl_obj *obj, enum nftnl_parse_type type,
396 FILE *fp, struct nftnl_parse_err *err)
397{
398 errno = EOPNOTSUPP;
399
400 return -1;
401}
402
403static int nftnl_obj_snprintf_dflt(char *buf, size_t remain,
404 const struct nftnl_obj *obj,
405 uint32_t type, uint32_t flags)
406{
407 const char *name = obj->ops ? obj->ops->name : "(unknown)";
408 int ret, offset = 0;
409
410 ret = snprintf(buf, remain, "table %s name %s use %u [ %s ",
411 obj->table, obj->name, obj->use, name);
412 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
413
414 if (obj->ops) {
415 ret = obj->ops->output(buf + offset, remain, flags, obj);
416 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
417 }
418 ret = snprintf(buf + offset, remain, "]");
419 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
420
421 return offset;
422}
423
424static int nftnl_obj_cmd_snprintf(char *buf, size_t remain,
425 const struct nftnl_obj *obj, uint32_t cmd,
426 uint32_t type, uint32_t flags)
427{
428 int ret, offset = 0;
429
430 if (type != NFTNL_OUTPUT_DEFAULT)
431 return -1;
432
433 ret = nftnl_obj_snprintf_dflt(buf + offset, remain, obj, type, flags);
434 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
435 return offset;
436}
437
438EXPORT_SYMBOL(nftnl_obj_snprintf);
439int nftnl_obj_snprintf(char *buf, size_t size, const struct nftnl_obj *obj,
440 uint32_t type, uint32_t flags)
441{
442 if (size)
443 buf[0] = '\0';
444
445 return nftnl_obj_cmd_snprintf(buf, size, obj, nftnl_flag2cmd(flags),
446 type, flags);
447}
448
449static int nftnl_obj_do_snprintf(char *buf, size_t size, const void *obj,
450 uint32_t cmd, uint32_t type, uint32_t flags)
451{
452 return nftnl_obj_snprintf(buf, size, obj, type, flags);
453}
454
455EXPORT_SYMBOL(nftnl_obj_fprintf);
456int nftnl_obj_fprintf(FILE *fp, const struct nftnl_obj *obj, uint32_t type,
457 uint32_t flags)
458{
459 return nftnl_fprintf(fp, obj, NFTNL_CMD_UNSPEC, type, flags,
460 nftnl_obj_do_snprintf);
461}
462
464 struct list_head list;
465};
466
467EXPORT_SYMBOL(nftnl_obj_list_alloc);
468struct nftnl_obj_list *nftnl_obj_list_alloc(void)
469{
470 struct nftnl_obj_list *list;
471
472 list = calloc(1, sizeof(struct nftnl_obj_list));
473 if (list == NULL)
474 return NULL;
475
476 INIT_LIST_HEAD(&list->list);
477
478 return list;
479}
480
481EXPORT_SYMBOL(nftnl_obj_list_free);
482void nftnl_obj_list_free(struct nftnl_obj_list *list)
483{
484 struct nftnl_obj *r, *tmp;
485
486 list_for_each_entry_safe(r, tmp, &list->list, head) {
487 list_del(&r->head);
488 nftnl_obj_free(r);
489 }
490 xfree(list);
491}
492
493EXPORT_SYMBOL(nftnl_obj_list_is_empty);
494int nftnl_obj_list_is_empty(struct nftnl_obj_list *list)
495{
496 return list_empty(&list->list);
497}
498
499EXPORT_SYMBOL(nftnl_obj_list_add);
500void nftnl_obj_list_add(struct nftnl_obj *r, struct nftnl_obj_list *list)
501{
502 list_add(&r->head, &list->list);
503}
504
505EXPORT_SYMBOL(nftnl_obj_list_add_tail);
506void nftnl_obj_list_add_tail(struct nftnl_obj *r,
507 struct nftnl_obj_list *list)
508{
509 list_add_tail(&r->head, &list->list);
510}
511
512EXPORT_SYMBOL(nftnl_obj_list_del);
513void nftnl_obj_list_del(struct nftnl_obj *t)
514{
515 list_del(&t->head);
516}
517
518EXPORT_SYMBOL(nftnl_obj_list_foreach);
519int nftnl_obj_list_foreach(struct nftnl_obj_list *table_list,
520 int (*cb)(struct nftnl_obj *t, void *data),
521 void *data)
522{
523 struct nftnl_obj *cur, *tmp;
524 int ret;
525
526 list_for_each_entry_safe(cur, tmp, &table_list->list, head) {
527 ret = cb(cur, data);
528 if (ret < 0)
529 return ret;
530 }
531 return 0;
532}
533
535 struct nftnl_obj_list *list;
536 struct nftnl_obj *cur;
537};
538
539EXPORT_SYMBOL(nftnl_obj_list_iter_create);
540struct nftnl_obj_list_iter *
541nftnl_obj_list_iter_create(struct nftnl_obj_list *l)
542{
543 struct nftnl_obj_list_iter *iter;
544
545 iter = calloc(1, sizeof(struct nftnl_obj_list_iter));
546 if (iter == NULL)
547 return NULL;
548
549 iter->list = l;
550 if (nftnl_obj_list_is_empty(l))
551 iter->cur = NULL;
552 else
553 iter->cur = list_entry(l->list.next, struct nftnl_obj, head);
554
555 return iter;
556}
557
558EXPORT_SYMBOL(nftnl_obj_list_iter_next);
559struct nftnl_obj *nftnl_obj_list_iter_next(struct nftnl_obj_list_iter *iter)
560{
561 struct nftnl_obj *r = iter->cur;
562
563 if (r == NULL)
564 return NULL;
565
566 /* get next table, if any */
567 iter->cur = list_entry(iter->cur->head.next, struct nftnl_obj, head);
568 if (&iter->cur->head == iter->list->list.next)
569 return NULL;
570
571 return r;
572}
573
574EXPORT_SYMBOL(nftnl_obj_list_iter_destroy);
575void nftnl_obj_list_iter_destroy(struct nftnl_obj_list_iter *iter)
576{
577 xfree(iter);
578}