libnftnl 1.2.8
object.c
1/*
2 * (C) 2012-2016 by Pablo Neira Ayuso <pablo@netfilter.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published
6 * by the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 */
9#include "internal.h"
10
11#include <time.h>
12#include <endian.h>
13#include <stdint.h>
14#include <limits.h>
15#include <stdlib.h>
16#include <string.h>
17#include <netinet/in.h>
18#include <errno.h>
19
20#include <libmnl/libmnl.h>
21#include <linux/netfilter/nfnetlink.h>
22#include <linux/netfilter/nf_tables.h>
23
24#include <libnftnl/object.h>
25#include "obj.h"
26
27static struct obj_ops *obj_ops[__NFT_OBJECT_MAX] = {
28 [NFT_OBJECT_COUNTER] = &obj_ops_counter,
29 [NFT_OBJECT_QUOTA] = &obj_ops_quota,
30 [NFT_OBJECT_CT_HELPER] = &obj_ops_ct_helper,
31 [NFT_OBJECT_LIMIT] = &obj_ops_limit,
32 [NFT_OBJECT_TUNNEL] = &obj_ops_tunnel,
33 [NFT_OBJECT_CT_TIMEOUT] = &obj_ops_ct_timeout,
34 [NFT_OBJECT_SECMARK] = &obj_ops_secmark,
35 [NFT_OBJECT_CT_EXPECT] = &obj_ops_ct_expect,
36 [NFT_OBJECT_SYNPROXY] = &obj_ops_synproxy,
37};
38
39static struct obj_ops *nftnl_obj_ops_lookup(uint32_t type)
40{
41 if (type > NFT_OBJECT_MAX)
42 return NULL;
43
44 return obj_ops[type];
45}
46
47EXPORT_SYMBOL(nftnl_obj_alloc);
48struct nftnl_obj *nftnl_obj_alloc(void)
49{
50 return calloc(1, sizeof(struct nftnl_obj));
51}
52
53EXPORT_SYMBOL(nftnl_obj_free);
54void nftnl_obj_free(const struct nftnl_obj *obj)
55{
56 if (obj->flags & (1 << NFTNL_OBJ_TABLE))
57 xfree(obj->table);
58 if (obj->flags & (1 << NFTNL_OBJ_NAME))
59 xfree(obj->name);
60 if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
61 xfree(obj->user.data);
62
63 xfree(obj);
64}
65
66EXPORT_SYMBOL(nftnl_obj_is_set);
67bool nftnl_obj_is_set(const struct nftnl_obj *obj, uint16_t attr)
68{
69 return obj->flags & (1 << attr);
70}
71
72EXPORT_SYMBOL(nftnl_obj_unset);
73void nftnl_obj_unset(struct nftnl_obj *obj, uint16_t attr)
74{
75 if (!(obj->flags & (1 << attr)))
76 return;
77
78 switch (attr) {
79 case NFTNL_OBJ_TABLE:
80 xfree(obj->table);
81 break;
82 case NFTNL_OBJ_NAME:
83 xfree(obj->name);
84 break;
85 case NFTNL_OBJ_USERDATA:
86 xfree(obj->user.data);
87 break;
88 case NFTNL_OBJ_TYPE:
89 case NFTNL_OBJ_FAMILY:
90 case NFTNL_OBJ_USE:
91 case NFTNL_OBJ_HANDLE:
92 break;
93 default:
94 break;
95 }
96
97 obj->flags &= ~(1 << attr);
98}
99
100static uint32_t nftnl_obj_validate[NFTNL_OBJ_MAX + 1] = {
101 [NFTNL_OBJ_TYPE] = sizeof(uint32_t),
102 [NFTNL_OBJ_FAMILY] = sizeof(uint32_t),
103 [NFTNL_OBJ_USE] = sizeof(uint32_t),
104 [NFTNL_OBJ_HANDLE] = sizeof(uint64_t),
105};
106
107EXPORT_SYMBOL(nftnl_obj_set_data);
108int nftnl_obj_set_data(struct nftnl_obj *obj, uint16_t attr,
109 const void *data, uint32_t data_len)
110{
111 if (attr < NFTNL_OBJ_MAX)
112 nftnl_assert_validate(data, nftnl_obj_validate, attr, data_len);
113
114 switch (attr) {
115 case NFTNL_OBJ_TABLE:
116 return nftnl_set_str_attr(&obj->table, &obj->flags,
117 attr, data, data_len);
118 break;
119 case NFTNL_OBJ_NAME:
120 return nftnl_set_str_attr(&obj->name, &obj->flags,
121 attr, data, data_len);
122 case NFTNL_OBJ_TYPE:
123 obj->ops = nftnl_obj_ops_lookup(*((uint32_t *)data));
124 if (!obj->ops)
125 return -1;
126 break;
127 case NFTNL_OBJ_FAMILY:
128 memcpy(&obj->family, data, sizeof(obj->family));
129 break;
130 case NFTNL_OBJ_USE:
131 memcpy(&obj->use, data, sizeof(obj->use));
132 break;
133 case NFTNL_OBJ_HANDLE:
134 memcpy(&obj->handle, data, sizeof(obj->handle));
135 break;
136 case NFTNL_OBJ_USERDATA:
137 if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
138 xfree(obj->user.data);
139
140 obj->user.data = malloc(data_len);
141 if (!obj->user.data)
142 return -1;
143 memcpy(obj->user.data, data, data_len);
144 obj->user.len = data_len;
145 break;
146 default:
147 if (!obj->ops ||
148 attr < NFTNL_OBJ_BASE ||
149 attr > obj->ops->nftnl_max_attr ||
150 !obj->ops->attr_policy)
151 return -1;
152
153 if (obj->ops->attr_policy[attr].maxlen &&
154 obj->ops->attr_policy[attr].maxlen < data_len)
155 return -1;
156
157 if (obj->ops->set(obj, attr, data, data_len) < 0)
158 return -1;
159 }
160 obj->flags |= (1 << attr);
161 return 0;
162}
163
164void nftnl_obj_set(struct nftnl_obj *obj, uint16_t attr, const void *data) __visible;
165void nftnl_obj_set(struct nftnl_obj *obj, uint16_t attr, const void *data)
166{
167 nftnl_obj_set_data(obj, attr, data, nftnl_obj_validate[attr]);
168}
169
170EXPORT_SYMBOL(nftnl_obj_set_u8);
171int nftnl_obj_set_u8(struct nftnl_obj *obj, uint16_t attr, uint8_t val)
172{
173 return nftnl_obj_set_data(obj, attr, &val, sizeof(uint8_t));
174}
175
176EXPORT_SYMBOL(nftnl_obj_set_u16);
177int nftnl_obj_set_u16(struct nftnl_obj *obj, uint16_t attr, uint16_t val)
178{
179 return nftnl_obj_set_data(obj, attr, &val, sizeof(uint16_t));
180}
181
182EXPORT_SYMBOL(nftnl_obj_set_u32);
183int nftnl_obj_set_u32(struct nftnl_obj *obj, uint16_t attr, uint32_t val)
184{
185 return nftnl_obj_set_data(obj, attr, &val, sizeof(uint32_t));
186}
187
188EXPORT_SYMBOL(nftnl_obj_set_u64);
189int nftnl_obj_set_u64(struct nftnl_obj *obj, uint16_t attr, uint64_t val)
190{
191 return nftnl_obj_set_data(obj, attr, &val, sizeof(uint64_t));
192}
193
194EXPORT_SYMBOL(nftnl_obj_set_str);
195int nftnl_obj_set_str(struct nftnl_obj *obj, uint16_t attr, const char *str)
196{
197 return nftnl_obj_set_data(obj, attr, str, strlen(str) + 1);
198}
199
200EXPORT_SYMBOL(nftnl_obj_get_data);
201const void *nftnl_obj_get_data(const struct nftnl_obj *obj, uint16_t attr,
202 uint32_t *data_len)
203{
204 if (!(obj->flags & (1 << attr)))
205 return NULL;
206
207 switch(attr) {
208 case NFTNL_OBJ_TABLE:
209 return obj->table;
210 case NFTNL_OBJ_NAME:
211 return obj->name;
212 case NFTNL_OBJ_TYPE:
213 if (!obj->ops)
214 return NULL;
215
216 *data_len = sizeof(uint32_t);
217 return &obj->ops->type;
218 case NFTNL_OBJ_FAMILY:
219 *data_len = sizeof(uint32_t);
220 return &obj->family;
221 case NFTNL_OBJ_USE:
222 *data_len = sizeof(uint32_t);
223 return &obj->use;
224 case NFTNL_OBJ_HANDLE:
225 *data_len = sizeof(uint64_t);
226 return &obj->handle;
227 case NFTNL_OBJ_USERDATA:
228 *data_len = obj->user.len;
229 return obj->user.data;
230 default:
231 if (obj->ops)
232 return obj->ops->get(obj, attr, data_len);
233 break;
234 }
235 return NULL;
236}
237
238EXPORT_SYMBOL(nftnl_obj_get);
239const void *nftnl_obj_get(const struct nftnl_obj *obj, uint16_t attr)
240{
241 uint32_t data_len;
242 return nftnl_obj_get_data(obj, attr, &data_len);
243}
244
245EXPORT_SYMBOL(nftnl_obj_get_u8);
246uint8_t nftnl_obj_get_u8(const struct nftnl_obj *obj, uint16_t attr)
247{
248 const void *ret = nftnl_obj_get(obj, attr);
249 return ret == NULL ? 0 : *((uint8_t *)ret);
250}
251
252EXPORT_SYMBOL(nftnl_obj_get_u16);
253uint16_t nftnl_obj_get_u16(const struct nftnl_obj *obj, uint16_t attr)
254{
255 const void *ret = nftnl_obj_get(obj, attr);
256 return ret == NULL ? 0 : *((uint16_t *)ret);
257}
258
259EXPORT_SYMBOL(nftnl_obj_get_u32);
260uint32_t nftnl_obj_get_u32(const struct nftnl_obj *obj, uint16_t attr)
261{
262 const void *ret = nftnl_obj_get(obj, attr);
263 return ret == NULL ? 0 : *((uint32_t *)ret);
264}
265
266EXPORT_SYMBOL(nftnl_obj_get_u64);
267uint64_t nftnl_obj_get_u64(const struct nftnl_obj *obj, uint16_t attr)
268{
269 const void *ret = nftnl_obj_get(obj, attr);
270 return ret == NULL ? 0 : *((uint64_t *)ret);
271}
272
273EXPORT_SYMBOL(nftnl_obj_get_str);
274const char *nftnl_obj_get_str(const struct nftnl_obj *obj, uint16_t attr)
275{
276 return nftnl_obj_get(obj, attr);
277}
278
279EXPORT_SYMBOL(nftnl_obj_nlmsg_build_payload);
280void nftnl_obj_nlmsg_build_payload(struct nlmsghdr *nlh,
281 const struct nftnl_obj *obj)
282{
283 if (obj->flags & (1 << NFTNL_OBJ_TABLE))
284 mnl_attr_put_strz(nlh, NFTA_OBJ_TABLE, obj->table);
285 if (obj->flags & (1 << NFTNL_OBJ_NAME))
286 mnl_attr_put_strz(nlh, NFTA_OBJ_NAME, obj->name);
287 if (obj->flags & (1 << NFTNL_OBJ_TYPE))
288 mnl_attr_put_u32(nlh, NFTA_OBJ_TYPE, htonl(obj->ops->type));
289 if (obj->flags & (1 << NFTNL_OBJ_HANDLE))
290 mnl_attr_put_u64(nlh, NFTA_OBJ_HANDLE, htobe64(obj->handle));
291 if (obj->flags & (1 << NFTNL_OBJ_USERDATA))
292 mnl_attr_put(nlh, NFTA_OBJ_USERDATA, obj->user.len, obj->user.data);
293 if (obj->ops) {
294 struct nlattr *nest = mnl_attr_nest_start(nlh, NFTA_OBJ_DATA);
295
296 obj->ops->build(nlh, obj);
297 mnl_attr_nest_end(nlh, nest);
298 }
299}
300
301static int nftnl_obj_parse_attr_cb(const struct nlattr *attr, void *data)
302{
303 const struct nlattr **tb = data;
304 int type = mnl_attr_get_type(attr);
305
306 if (mnl_attr_type_valid(attr, NFTA_OBJ_MAX) < 0)
307 return MNL_CB_OK;
308
309 switch(type) {
310 case NFTA_OBJ_TABLE:
311 case NFTA_OBJ_NAME:
312 if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
313 abi_breakage();
314 break;
315 case NFTA_OBJ_HANDLE:
316 if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
317 abi_breakage();
318 break;
319 case NFTA_OBJ_DATA:
320 if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0)
321 abi_breakage();
322 break;
323 case NFTA_OBJ_USE:
324 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
325 abi_breakage();
326 break;
327 case NFTA_OBJ_USERDATA:
328 if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0)
329 abi_breakage();
330 break;
331 }
332
333 tb[type] = attr;
334 return MNL_CB_OK;
335}
336
337EXPORT_SYMBOL(nftnl_obj_nlmsg_parse);
338int nftnl_obj_nlmsg_parse(const struct nlmsghdr *nlh, struct nftnl_obj *obj)
339{
340 struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh);
341 struct nlattr *tb[NFTA_OBJ_MAX + 1] = {};
342 int err;
343
344 if (mnl_attr_parse(nlh, sizeof(*nfg), nftnl_obj_parse_attr_cb, tb) < 0)
345 return -1;
346
347 if (tb[NFTA_OBJ_TABLE]) {
348 obj->table = strdup(mnl_attr_get_str(tb[NFTA_OBJ_TABLE]));
349 obj->flags |= (1 << NFTNL_OBJ_TABLE);
350 }
351 if (tb[NFTA_OBJ_NAME]) {
352 obj->name = strdup(mnl_attr_get_str(tb[NFTA_OBJ_NAME]));
353 obj->flags |= (1 << NFTNL_OBJ_NAME);
354 }
355 if (tb[NFTA_OBJ_TYPE]) {
356 uint32_t type = ntohl(mnl_attr_get_u32(tb[NFTA_OBJ_TYPE]));
357
358 obj->ops = nftnl_obj_ops_lookup(type);
359 if (obj->ops)
360 obj->flags |= (1 << NFTNL_OBJ_TYPE);
361 }
362 if (tb[NFTA_OBJ_DATA]) {
363 if (obj->ops) {
364 err = obj->ops->parse(obj, tb[NFTA_OBJ_DATA]);
365 if (err < 0)
366 return err;
367 }
368 }
369 if (tb[NFTA_OBJ_USE]) {
370 obj->use = ntohl(mnl_attr_get_u32(tb[NFTA_OBJ_USE]));
371 obj->flags |= (1 << NFTNL_OBJ_USE);
372 }
373 if (tb[NFTA_OBJ_HANDLE]) {
374 obj->handle = be64toh(mnl_attr_get_u64(tb[NFTA_OBJ_HANDLE]));
375 obj->flags |= (1 << NFTNL_OBJ_HANDLE);
376 }
377 if (tb[NFTA_OBJ_USERDATA]) {
378 nftnl_obj_set_data(obj, NFTNL_OBJ_USERDATA,
379 mnl_attr_get_payload(tb[NFTA_OBJ_USERDATA]),
380 mnl_attr_get_payload_len(tb[NFTA_OBJ_USERDATA]));
381 }
382
383 obj->family = nfg->nfgen_family;
384 obj->flags |= (1 << NFTNL_OBJ_FAMILY);
385
386 return 0;
387}
388
389EXPORT_SYMBOL(nftnl_obj_parse);
390int nftnl_obj_parse(struct nftnl_obj *obj, enum nftnl_parse_type type,
391 const char *data, struct nftnl_parse_err *err)
392{
393 errno = EOPNOTSUPP;
394
395 return -1;
396}
397
398EXPORT_SYMBOL(nftnl_obj_parse_file);
399int nftnl_obj_parse_file(struct nftnl_obj *obj, enum nftnl_parse_type type,
400 FILE *fp, struct nftnl_parse_err *err)
401{
402 errno = EOPNOTSUPP;
403
404 return -1;
405}
406
407static int nftnl_obj_snprintf_dflt(char *buf, size_t remain,
408 const struct nftnl_obj *obj,
409 uint32_t type, uint32_t flags)
410{
411 const char *name = obj->ops ? obj->ops->name : "(unknown)";
412 int ret, offset = 0;
413
414 ret = snprintf(buf, remain, "table %s name %s use %u [ %s ",
415 obj->table, obj->name, obj->use, name);
416 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
417
418 if (obj->ops) {
419 ret = obj->ops->output(buf + offset, remain, flags, obj);
420 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
421 }
422 ret = snprintf(buf + offset, remain, "]");
423 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
424
425 return offset;
426}
427
428static int nftnl_obj_cmd_snprintf(char *buf, size_t remain,
429 const struct nftnl_obj *obj, uint32_t cmd,
430 uint32_t type, uint32_t flags)
431{
432 int ret, offset = 0;
433
434 if (type != NFTNL_OUTPUT_DEFAULT)
435 return -1;
436
437 ret = nftnl_obj_snprintf_dflt(buf + offset, remain, obj, type, flags);
438 SNPRINTF_BUFFER_SIZE(ret, remain, offset);
439 return offset;
440}
441
442EXPORT_SYMBOL(nftnl_obj_snprintf);
443int nftnl_obj_snprintf(char *buf, size_t size, const struct nftnl_obj *obj,
444 uint32_t type, uint32_t flags)
445{
446 if (size)
447 buf[0] = '\0';
448
449 return nftnl_obj_cmd_snprintf(buf, size, obj, nftnl_flag2cmd(flags),
450 type, flags);
451}
452
453static int nftnl_obj_do_snprintf(char *buf, size_t size, const void *obj,
454 uint32_t cmd, uint32_t type, uint32_t flags)
455{
456 return nftnl_obj_snprintf(buf, size, obj, type, flags);
457}
458
459EXPORT_SYMBOL(nftnl_obj_fprintf);
460int nftnl_obj_fprintf(FILE *fp, const struct nftnl_obj *obj, uint32_t type,
461 uint32_t flags)
462{
463 return nftnl_fprintf(fp, obj, NFTNL_CMD_UNSPEC, type, flags,
464 nftnl_obj_do_snprintf);
465}
466
468 struct list_head list;
469};
470
471EXPORT_SYMBOL(nftnl_obj_list_alloc);
472struct nftnl_obj_list *nftnl_obj_list_alloc(void)
473{
474 struct nftnl_obj_list *list;
475
476 list = calloc(1, sizeof(struct nftnl_obj_list));
477 if (list == NULL)
478 return NULL;
479
480 INIT_LIST_HEAD(&list->list);
481
482 return list;
483}
484
485EXPORT_SYMBOL(nftnl_obj_list_free);
486void nftnl_obj_list_free(struct nftnl_obj_list *list)
487{
488 struct nftnl_obj *r, *tmp;
489
490 list_for_each_entry_safe(r, tmp, &list->list, head) {
491 list_del(&r->head);
492 nftnl_obj_free(r);
493 }
494 xfree(list);
495}
496
497EXPORT_SYMBOL(nftnl_obj_list_is_empty);
498int nftnl_obj_list_is_empty(struct nftnl_obj_list *list)
499{
500 return list_empty(&list->list);
501}
502
503EXPORT_SYMBOL(nftnl_obj_list_add);
504void nftnl_obj_list_add(struct nftnl_obj *r, struct nftnl_obj_list *list)
505{
506 list_add(&r->head, &list->list);
507}
508
509EXPORT_SYMBOL(nftnl_obj_list_add_tail);
510void nftnl_obj_list_add_tail(struct nftnl_obj *r,
511 struct nftnl_obj_list *list)
512{
513 list_add_tail(&r->head, &list->list);
514}
515
516EXPORT_SYMBOL(nftnl_obj_list_del);
517void nftnl_obj_list_del(struct nftnl_obj *t)
518{
519 list_del(&t->head);
520}
521
522EXPORT_SYMBOL(nftnl_obj_list_foreach);
523int nftnl_obj_list_foreach(struct nftnl_obj_list *table_list,
524 int (*cb)(struct nftnl_obj *t, void *data),
525 void *data)
526{
527 struct nftnl_obj *cur, *tmp;
528 int ret;
529
530 list_for_each_entry_safe(cur, tmp, &table_list->list, head) {
531 ret = cb(cur, data);
532 if (ret < 0)
533 return ret;
534 }
535 return 0;
536}
537
539 struct nftnl_obj_list *list;
540 struct nftnl_obj *cur;
541};
542
543EXPORT_SYMBOL(nftnl_obj_list_iter_create);
544struct nftnl_obj_list_iter *
545nftnl_obj_list_iter_create(struct nftnl_obj_list *l)
546{
547 struct nftnl_obj_list_iter *iter;
548
549 iter = calloc(1, sizeof(struct nftnl_obj_list_iter));
550 if (iter == NULL)
551 return NULL;
552
553 iter->list = l;
554 if (nftnl_obj_list_is_empty(l))
555 iter->cur = NULL;
556 else
557 iter->cur = list_entry(l->list.next, struct nftnl_obj, head);
558
559 return iter;
560}
561
562EXPORT_SYMBOL(nftnl_obj_list_iter_next);
563struct nftnl_obj *nftnl_obj_list_iter_next(struct nftnl_obj_list_iter *iter)
564{
565 struct nftnl_obj *r = iter->cur;
566
567 if (r == NULL)
568 return NULL;
569
570 /* get next table, if any */
571 iter->cur = list_entry(iter->cur->head.next, struct nftnl_obj, head);
572 if (&iter->cur->head == iter->list->list.next)
573 return NULL;
574
575 return r;
576}
577
578EXPORT_SYMBOL(nftnl_obj_list_iter_destroy);
579void nftnl_obj_list_iter_destroy(struct nftnl_obj_list_iter *iter)
580{
581 xfree(iter);
582}