xref: /aosp_15_r20/external/libnl/lib/route/rule.c (revision 4dc78e53d49367fa8e61b07018507c90983a077d)
1 /* SPDX-License-Identifier: LGPL-2.1-only */
2 /*
3  * Copyright (c) 2003-2010 Thomas Graf <[email protected]>
4  */
5 
6 /**
7  * @ingroup rtnl
8  * @defgroup rule Routing Rules
9  * @brief
10  * @{
11  */
12 
13 #include "nl-default.h"
14 
15 #include <linux/fib_rules.h>
16 
17 #include <netlink/netlink.h>
18 #include <netlink/utils.h>
19 #include <netlink/route/rtnl.h>
20 #include <netlink/route/rule.h>
21 
22 #include "nl-route.h"
23 #include "nl-priv-dynamic-core/nl-core.h"
24 #include "nl-priv-dynamic-core/cache-api.h"
25 
26 /** @cond SKIP */
27 struct rtnl_rule {
28 	NLHDR_COMMON
29 	uint8_t r_family;
30 	uint8_t r_action;
31 	uint8_t r_dsfield; /* ipv4 only */
32 	uint8_t r_l3mdev;
33 	uint8_t r_protocol; /* protocol that installed rule */
34 	uint8_t r_ip_proto; /* IP/IPv6 protocol */
35 	uint32_t r_table;
36 	uint32_t r_flags;
37 	uint32_t r_prio;
38 	uint32_t r_mark;
39 	uint32_t r_mask;
40 	uint32_t r_goto;
41 	uint32_t r_flow; /* ipv4 only */
42 	struct nl_addr *r_src;
43 	struct nl_addr *r_dst;
44 	char r_iifname[IFNAMSIZ];
45 	char r_oifname[IFNAMSIZ];
46 
47 	struct fib_rule_port_range r_sport;
48 	struct fib_rule_port_range r_dport;
49 };
50 
51 #define RULE_ATTR_FAMILY	0x000001
52 #define RULE_ATTR_TABLE		0x000002
53 #define RULE_ATTR_ACTION	0x000004
54 #define RULE_ATTR_FLAGS		0x000008
55 #define RULE_ATTR_IIFNAME	0x000010
56 #define RULE_ATTR_OIFNAME	0x000020
57 #define RULE_ATTR_PRIO		0x000040
58 #define RULE_ATTR_MARK		0x000080
59 #define RULE_ATTR_MASK		0x000100
60 #define RULE_ATTR_GOTO		0x000200
61 #define RULE_ATTR_SRC		0x000400
62 #define RULE_ATTR_DST		0x000800
63 #define RULE_ATTR_DSFIELD	0x001000
64 #define RULE_ATTR_FLOW		0x002000
65 #define RULE_ATTR_L3MDEV	0x004000
66 #define RULE_ATTR_PROTOCOL	0x008000
67 #define RULE_ATTR_IP_PROTO	0x010000
68 #define RULE_ATTR_SPORT		0x020000
69 #define RULE_ATTR_DPORT		0x040000
70 
71 static struct nl_cache_ops rtnl_rule_ops;
72 static struct nl_object_ops rule_obj_ops;
73 /** @endcond */
74 
rule_free_data(struct nl_object * c)75 static void rule_free_data(struct nl_object *c)
76 {
77 	struct rtnl_rule *rule = nl_object_priv(c);
78 
79 	if (!rule)
80 		return;
81 
82 	nl_addr_put(rule->r_src);
83 	nl_addr_put(rule->r_dst);
84 }
85 
rule_clone(struct nl_object * _dst,struct nl_object * _src)86 static int rule_clone(struct nl_object *_dst, struct nl_object *_src)
87 {
88 	struct rtnl_rule *dst = nl_object_priv(_dst);
89 	struct rtnl_rule *src = nl_object_priv(_src);
90 
91 	dst->r_src = NULL;
92 	dst->r_dst = NULL;
93 
94 	if (src->r_src)
95 		if (!(dst->r_src = nl_addr_clone(src->r_src)))
96 			return -NLE_NOMEM;
97 
98 	if (src->r_dst)
99 		if (!(dst->r_dst = nl_addr_clone(src->r_dst)))
100 			return -NLE_NOMEM;
101 
102 	return 0;
103 }
104 
105 static struct nla_policy rule_policy[FRA_MAX+1] = {
106 	[FRA_TABLE]	= { .type = NLA_U32 },
107 	[FRA_IIFNAME]	= { .type = NLA_STRING, .maxlen = IFNAMSIZ },
108 	[FRA_OIFNAME]	= { .type = NLA_STRING, .maxlen = IFNAMSIZ },
109 	[FRA_PRIORITY]	= { .type = NLA_U32 },
110 	[FRA_FWMARK]	= { .type = NLA_U32 },
111 	[FRA_FWMASK]	= { .type = NLA_U32 },
112 	[FRA_GOTO]	= { .type = NLA_U32 },
113 	[FRA_FLOW]	= { .type = NLA_U32 },
114 	[FRA_L3MDEV]	= { .type = NLA_U8 },
115 	[FRA_PROTOCOL]	= { .type = NLA_U8 },
116 	[FRA_IP_PROTO]	= { .type = NLA_U8 },
117 	[FRA_SPORT_RANGE] = { .minlen = sizeof(struct fib_rule_port_range),
118 			      .maxlen = sizeof(struct fib_rule_port_range) },
119 	[FRA_DPORT_RANGE] = { .minlen = sizeof(struct fib_rule_port_range),
120 			      .maxlen = sizeof(struct fib_rule_port_range) },
121 };
122 
rule_msg_parser(struct nl_cache_ops * ops,struct sockaddr_nl * who,struct nlmsghdr * n,struct nl_parser_param * pp)123 static int rule_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
124 			   struct nlmsghdr *n, struct nl_parser_param *pp)
125 {
126 	struct rtnl_rule *rule;
127 	struct fib_rule_hdr *frh;
128 	struct nlattr *tb[FRA_MAX+1];
129 	int err = 1, family;
130 
131 	rule = rtnl_rule_alloc();
132 	if (!rule) {
133 		err = -NLE_NOMEM;
134 		goto errout;
135 	}
136 
137 	rule->ce_msgtype = n->nlmsg_type;
138 	frh = nlmsg_data(n);
139 
140 	err = nlmsg_parse(n, sizeof(*frh), tb, FRA_MAX, rule_policy);
141 	if (err < 0)
142 		goto errout;
143 
144 	rule->r_family = family = frh->family;
145 	rule->r_table = frh->table;
146 	rule->r_action = frh->action;
147 	rule->r_flags = frh->flags;
148 
149 	rule->ce_mask = (RULE_ATTR_FAMILY | RULE_ATTR_ACTION | RULE_ATTR_FLAGS);
150 	if (rule->r_table)
151 		rule->ce_mask |= RULE_ATTR_TABLE;
152 
153 	/* ipv4 only */
154 	if (frh->tos) {
155 		rule->r_dsfield = frh->tos;
156 		rule->ce_mask |= RULE_ATTR_DSFIELD;
157 	}
158 
159 	if (tb[FRA_TABLE]) {
160 		rule->r_table = nla_get_u32(tb[FRA_TABLE]);
161 		if (rule->r_table)
162 			rule->ce_mask |= RULE_ATTR_TABLE;
163 	}
164 
165 	if (tb[FRA_IIFNAME]) {
166 		nla_strlcpy(rule->r_iifname, tb[FRA_IIFNAME], IFNAMSIZ);
167 		rule->ce_mask |= RULE_ATTR_IIFNAME;
168 	}
169 
170 	if (tb[FRA_OIFNAME]) {
171 		nla_strlcpy(rule->r_oifname, tb[FRA_OIFNAME], IFNAMSIZ);
172 		rule->ce_mask |= RULE_ATTR_OIFNAME;
173 	}
174 
175 	if (tb[FRA_PRIORITY]) {
176 		rule->r_prio = nla_get_u32(tb[FRA_PRIORITY]);
177 		rule->ce_mask |= RULE_ATTR_PRIO;
178 	}
179 
180 	if (tb[FRA_FWMARK]) {
181 		rule->r_mark = nla_get_u32(tb[FRA_FWMARK]);
182 		rule->ce_mask |= RULE_ATTR_MARK;
183 	}
184 
185 	if (tb[FRA_FWMASK]) {
186 		rule->r_mask = nla_get_u32(tb[FRA_FWMASK]);
187 		rule->ce_mask |= RULE_ATTR_MASK;
188 	}
189 
190 	if (tb[FRA_GOTO]) {
191 		rule->r_goto = nla_get_u32(tb[FRA_GOTO]);
192 		rule->ce_mask |= RULE_ATTR_GOTO;
193 	}
194 
195 	if (tb[FRA_SRC]) {
196 		if (!(rule->r_src = nl_addr_alloc_attr(tb[FRA_SRC], family)))
197 			goto errout_enomem;
198 
199 		nl_addr_set_prefixlen(rule->r_src, frh->src_len);
200 		rule->ce_mask |= RULE_ATTR_SRC;
201 	}
202 
203 	if (tb[FRA_DST]) {
204 		if (!(rule->r_dst = nl_addr_alloc_attr(tb[FRA_DST], family)))
205 			goto errout_enomem;
206 		nl_addr_set_prefixlen(rule->r_dst, frh->dst_len);
207 		rule->ce_mask |= RULE_ATTR_DST;
208 	}
209 
210 	/* ipv4 only */
211 	if (tb[FRA_FLOW]) {
212 		rule->r_flow = nla_get_u32(tb[FRA_FLOW]);
213 		rule->ce_mask |= RULE_ATTR_FLOW;
214 	}
215 
216 	if (tb[FRA_L3MDEV]) {
217 		rule->r_l3mdev = nla_get_u8(tb[FRA_L3MDEV]);
218 		rule->ce_mask |= RULE_ATTR_L3MDEV;
219 	}
220 
221 	if (tb[FRA_PROTOCOL]) {
222 		rule->r_protocol = nla_get_u8(tb[FRA_PROTOCOL]);
223 		rule->ce_mask |= RULE_ATTR_PROTOCOL;
224 	}
225 
226 	if (tb[FRA_IP_PROTO]) {
227 		rule->r_ip_proto = nla_get_u8(tb[FRA_IP_PROTO]);
228 		rule->ce_mask |= RULE_ATTR_IP_PROTO;
229 	}
230 
231 	if (tb[FRA_SPORT_RANGE]) {
232 		struct fib_rule_port_range *pr;
233 
234 		pr = nla_data(tb[FRA_SPORT_RANGE]);
235 		rule->r_sport = *pr;
236 		rule->ce_mask |= RULE_ATTR_SPORT;
237 	}
238 
239 	if (tb[FRA_DPORT_RANGE]) {
240 		struct fib_rule_port_range *pr;
241 
242 		pr = nla_data(tb[FRA_DPORT_RANGE]);
243 		rule->r_dport = *pr;
244 		rule->ce_mask |= RULE_ATTR_DPORT;
245 	}
246 
247 	err = pp->pp_cb((struct nl_object *) rule, pp);
248 errout:
249 	rtnl_rule_put(rule);
250 	return err;
251 
252 errout_enomem:
253 	err = -NLE_NOMEM;
254 	goto errout;
255 }
256 
rule_request_update(struct nl_cache * c,struct nl_sock * h)257 static int rule_request_update(struct nl_cache *c, struct nl_sock *h)
258 {
259 	return nl_rtgen_request(h, RTM_GETRULE, AF_UNSPEC, NLM_F_DUMP);
260 }
261 
rule_dump_line(struct nl_object * o,struct nl_dump_params * p)262 static void rule_dump_line(struct nl_object *o, struct nl_dump_params *p)
263 {
264 	struct rtnl_rule *r = (struct rtnl_rule *) o;
265 	char buf[128];
266 
267 	nl_dump_line(p, "%8d ", (r->ce_mask & RULE_ATTR_PRIO) ? r->r_prio : 0);
268 	nl_dump(p, "%s ", nl_af2str(r->r_family, buf, sizeof(buf)));
269 
270 	if (r->ce_mask & RULE_ATTR_SRC)
271 		nl_dump(p, "from %s ",
272 			nl_addr2str(r->r_src, buf, sizeof(buf)));
273 
274 	if (r->ce_mask & RULE_ATTR_DST)
275 		nl_dump(p, "to %s ",
276 			nl_addr2str(r->r_dst, buf, sizeof(buf)));
277 
278 	if (r->ce_mask & RULE_ATTR_DSFIELD)
279 		nl_dump(p, "tos %u ", r->r_dsfield);
280 
281 	if (r->ce_mask & (RULE_ATTR_MARK | RULE_ATTR_MASK))
282 		nl_dump(p, "mark %#x/%#x", r->r_mark, r->r_mask);
283 
284 	if (r->ce_mask & RULE_ATTR_IIFNAME)
285 		nl_dump(p, "iif %s ", r->r_iifname);
286 
287 	if (r->ce_mask & RULE_ATTR_OIFNAME)
288 		nl_dump(p, "oif %s ", r->r_oifname);
289 
290 	if (r->ce_mask & RULE_ATTR_TABLE)
291 		nl_dump(p, "lookup %s ",
292 			rtnl_route_table2str(r->r_table, buf, sizeof(buf)));
293 
294 	if (r->ce_mask & RULE_ATTR_L3MDEV)
295 		nl_dump(p, "lookup [l3mdev-table] ");
296 
297 	if (r->ce_mask & RULE_ATTR_IP_PROTO)
298 		nl_dump(p, "ipproto %s ",
299 			nl_ip_proto2str(r->r_ip_proto, buf, sizeof(buf)));
300 
301 	if (r->ce_mask & RULE_ATTR_SPORT) {
302 		if (r->r_sport.start == r->r_sport.end)
303 			nl_dump(p, "sport %u ", r->r_sport.start);
304 		else
305 			nl_dump(p, "sport %u-%u ",
306 				r->r_sport.start, r->r_sport.end);
307 	}
308 
309 	if (r->ce_mask & RULE_ATTR_DPORT) {
310 		if (r->r_dport.start == r->r_dport.end)
311 			nl_dump(p, "dport %u ", r->r_dport.start);
312 		else
313 			nl_dump(p, "dport %u-%u ",
314 				r->r_dport.start, r->r_dport.end);
315 	}
316 
317 	if (r->ce_mask & RULE_ATTR_PROTOCOL)
318 		nl_dump(p, "protocol %s ",
319 			rtnl_route_proto2str(r->r_protocol, buf, sizeof(buf)));
320 
321 	if (r->ce_mask & RULE_ATTR_FLOW)
322 		nl_dump(p, "flow %s ",
323 			rtnl_realms2str(r->r_flow, buf, sizeof(buf)));
324 
325 	if (r->ce_mask & RULE_ATTR_GOTO)
326 		nl_dump(p, "goto %u ", r->r_goto);
327 
328 	if (r->ce_mask & RULE_ATTR_ACTION)
329 		nl_dump(p, "action %s",
330 			nl_rtntype2str(r->r_action, buf, sizeof(buf)));
331 
332 	nl_dump(p, "\n");
333 }
334 
rule_dump_details(struct nl_object * obj,struct nl_dump_params * p)335 static void rule_dump_details(struct nl_object *obj, struct nl_dump_params *p)
336 {
337 	rule_dump_line(obj, p);
338 }
339 
rule_dump_stats(struct nl_object * obj,struct nl_dump_params * p)340 static void rule_dump_stats(struct nl_object *obj, struct nl_dump_params *p)
341 {
342 	rule_dump_details(obj, p);
343 }
344 
rule_compare(struct nl_object * _a,struct nl_object * _b,uint64_t attrs,int flags)345 static uint64_t rule_compare(struct nl_object *_a, struct nl_object *_b,
346 			     uint64_t attrs, int flags)
347 {
348 	struct rtnl_rule *a = (struct rtnl_rule *) _a;
349 	struct rtnl_rule *b = (struct rtnl_rule *) _b;
350 	uint64_t diff = 0;
351 
352 #define _DIFF(ATTR, EXPR) ATTR_DIFF(attrs, ATTR, a, b, EXPR)
353 	diff |= _DIFF(RULE_ATTR_FAMILY, a->r_family != b->r_family);
354 	diff |= _DIFF(RULE_ATTR_TABLE, a->r_table != b->r_table);
355 	diff |= _DIFF(RULE_ATTR_ACTION, a->r_action != b->r_action);
356 	diff |= _DIFF(RULE_ATTR_IIFNAME, strcmp(a->r_iifname, b->r_iifname));
357 	diff |= _DIFF(RULE_ATTR_OIFNAME, strcmp(a->r_oifname, b->r_oifname));
358 	diff |= _DIFF(RULE_ATTR_PRIO, a->r_prio != b->r_prio);
359 	diff |= _DIFF(RULE_ATTR_MARK, a->r_mark != b->r_mark);
360 	diff |= _DIFF(RULE_ATTR_MASK, a->r_mask != b->r_mask);
361 	diff |= _DIFF(RULE_ATTR_GOTO, a->r_goto != b->r_goto);
362 	diff |= _DIFF(RULE_ATTR_SRC, nl_addr_cmp(a->r_src, b->r_src));
363 	diff |= _DIFF(RULE_ATTR_DST, nl_addr_cmp(a->r_dst, b->r_dst));
364 	diff |= _DIFF(RULE_ATTR_DSFIELD, a->r_dsfield != b->r_dsfield);
365 	diff |= _DIFF(RULE_ATTR_FLOW, a->r_flow != b->r_flow);
366 #undef _DIFF
367 
368 	return diff;
369 }
370 
371 static const struct trans_tbl rule_attrs[] = {
372 	__ADD(RULE_ATTR_FAMILY, family),
373 	__ADD(RULE_ATTR_TABLE, table),
374 	__ADD(RULE_ATTR_ACTION, action),
375 	__ADD(RULE_ATTR_IIFNAME, iifname),
376 	__ADD(RULE_ATTR_OIFNAME, oifname),
377 	__ADD(RULE_ATTR_PRIO, prio),
378 	__ADD(RULE_ATTR_MARK, mark),
379 	__ADD(RULE_ATTR_MASK, mask),
380 	__ADD(RULE_ATTR_GOTO, goto),
381 	__ADD(RULE_ATTR_SRC, src),
382 	__ADD(RULE_ATTR_DST, dst),
383 	__ADD(RULE_ATTR_DSFIELD, dsfield),
384 	__ADD(RULE_ATTR_FLOW, flow),
385 };
386 
rule_attrs2str(int attrs,char * buf,size_t len)387 static char *rule_attrs2str(int attrs, char *buf, size_t len)
388 {
389 	return __flags2str(attrs, buf, len, rule_attrs,
390 			   ARRAY_SIZE(rule_attrs));
391 }
392 
393 /**
394  * @name Allocation/Freeing
395  * @{
396  */
397 
rtnl_rule_alloc(void)398 struct rtnl_rule *rtnl_rule_alloc(void)
399 {
400 	return (struct rtnl_rule *) nl_object_alloc(&rule_obj_ops);
401 }
402 
rtnl_rule_put(struct rtnl_rule * rule)403 void rtnl_rule_put(struct rtnl_rule *rule)
404 {
405 	nl_object_put((struct nl_object *) rule);
406 }
407 
408 /** @} */
409 
410 /**
411  * @name Cache Management
412  * @{
413  */
414 
415 /**
416  * Build a rule cache including all rules currently configured in the kernel.
417  * @arg sock		Netlink socket.
418  * @arg family		Address family or AF_UNSPEC.
419  * @arg result		Pointer to store resulting cache.
420  *
421  * Allocates a new rule cache, initializes it properly and updates it
422  * to include all rules currently configured in the kernel.
423  *
424  * @return 0 on success or a negative error code.
425  */
rtnl_rule_alloc_cache(struct nl_sock * sock,int family,struct nl_cache ** result)426 int rtnl_rule_alloc_cache(struct nl_sock *sock, int family,
427 			  struct nl_cache **result)
428 {
429 	struct nl_cache * cache;
430 	int err;
431 
432 	if (!(cache = nl_cache_alloc(&rtnl_rule_ops)))
433 		return -NLE_NOMEM;
434 
435 	cache->c_iarg1 = family;
436 
437 	if (sock && (err = nl_cache_refill(sock, cache)) < 0) {
438 		free(cache);
439 		return err;
440 	}
441 
442 	*result = cache;
443 	return 0;
444 }
445 
446 /** @} */
447 
448 /**
449  * @name Rule Addition
450  * @{
451  */
452 
build_rule_msg(struct rtnl_rule * tmpl,int cmd,int flags,struct nl_msg ** result)453 static int build_rule_msg(struct rtnl_rule *tmpl, int cmd, int flags,
454 			  struct nl_msg **result)
455 {
456 	struct nl_msg *msg;
457 	struct fib_rule_hdr frh = {
458 		.family = tmpl->r_family,
459 		.table = tmpl->r_table,
460 		.action = tmpl->r_action,
461 		.flags = tmpl->r_flags,
462 		.tos = tmpl->r_dsfield,
463 	};
464 
465 	if (!(tmpl->ce_mask & RULE_ATTR_FAMILY))
466 		return -NLE_MISSING_ATTR;
467 
468 	msg = nlmsg_alloc_simple(cmd, flags);
469 	if (!msg)
470 		return -NLE_NOMEM;
471 
472 	if (tmpl->ce_mask & RULE_ATTR_SRC)
473 		frh.src_len = nl_addr_get_prefixlen(tmpl->r_src);
474 
475 	if (tmpl->ce_mask & RULE_ATTR_DST)
476 		frh.dst_len = nl_addr_get_prefixlen(tmpl->r_dst);
477 
478 	if (nlmsg_append(msg, &frh, sizeof(frh), NLMSG_ALIGNTO) < 0)
479 		goto nla_put_failure;
480 
481 	/* Additional table attribute replacing the 8bit in the header, was
482 	 * required to allow more than 256 tables. */
483 	NLA_PUT_U32(msg, FRA_TABLE, tmpl->r_table);
484 
485 	if (tmpl->ce_mask & RULE_ATTR_SRC)
486 		NLA_PUT_ADDR(msg, FRA_SRC, tmpl->r_src);
487 
488 	if (tmpl->ce_mask & RULE_ATTR_DST)
489 		NLA_PUT_ADDR(msg, FRA_DST, tmpl->r_dst);
490 
491 	if (tmpl->ce_mask & RULE_ATTR_IIFNAME)
492 		NLA_PUT_STRING(msg, FRA_IIFNAME, tmpl->r_iifname);
493 
494 	if (tmpl->ce_mask & RULE_ATTR_OIFNAME)
495 		NLA_PUT_STRING(msg, FRA_OIFNAME, tmpl->r_oifname);
496 
497 	if (tmpl->ce_mask & RULE_ATTR_PRIO)
498 		NLA_PUT_U32(msg, FRA_PRIORITY, tmpl->r_prio);
499 
500 	if (tmpl->ce_mask & RULE_ATTR_MARK)
501 		NLA_PUT_U32(msg, FRA_FWMARK, tmpl->r_mark);
502 
503 	if (tmpl->ce_mask & RULE_ATTR_MASK)
504 		NLA_PUT_U32(msg, FRA_FWMASK, tmpl->r_mask);
505 
506 	if (tmpl->ce_mask & RULE_ATTR_GOTO)
507 		NLA_PUT_U32(msg, FRA_GOTO, tmpl->r_goto);
508 
509 	if (tmpl->ce_mask & RULE_ATTR_FLOW)
510 		NLA_PUT_U32(msg, FRA_FLOW, tmpl->r_flow);
511 
512 	if (tmpl->ce_mask & RULE_ATTR_L3MDEV)
513 		NLA_PUT_U8(msg, FRA_L3MDEV, tmpl->r_l3mdev);
514 
515 	if (tmpl->ce_mask & RULE_ATTR_IP_PROTO)
516 		NLA_PUT_U8(msg, FRA_IP_PROTO, tmpl->r_ip_proto);
517 
518 	if (tmpl->ce_mask & RULE_ATTR_SPORT)
519 		NLA_PUT(msg, FRA_SPORT_RANGE, sizeof(tmpl->r_sport),
520 			&tmpl->r_sport);
521 
522 	if (tmpl->ce_mask & RULE_ATTR_DPORT)
523 		NLA_PUT(msg, FRA_DPORT_RANGE, sizeof(tmpl->r_dport),
524 			&tmpl->r_dport);
525 
526 	if (tmpl->ce_mask & RULE_ATTR_PROTOCOL)
527 		NLA_PUT_U8(msg, FRA_PROTOCOL, tmpl->r_protocol);
528 
529 	*result = msg;
530 	return 0;
531 
532 nla_put_failure:
533 	nlmsg_free(msg);
534 	return -NLE_MSGSIZE;
535 }
536 
537 /**
538  * Build netlink request message to add a new rule
539  * @arg tmpl		template with data of new rule
540  * @arg flags		additional netlink message flags
541  * @arg result		Result pointer
542  *
543  * Builds a new netlink message requesting a addition of a new
544  * rule. The netlink message header isn't fully equipped with
545  * all relevant fields and must thus be sent out via nl_send_auto_complete()
546  * or supplemented as needed. \a tmpl must contain the attributes of the new
547  * address set via \c rtnl_rule_set_* functions.
548  *
549  * @return 0 on success or a negative error code.
550  */
rtnl_rule_build_add_request(struct rtnl_rule * tmpl,int flags,struct nl_msg ** result)551 int rtnl_rule_build_add_request(struct rtnl_rule *tmpl, int flags,
552 				struct nl_msg **result)
553 {
554 	return build_rule_msg(tmpl, RTM_NEWRULE, NLM_F_CREATE | flags,
555 			      result);
556 }
557 
558 /**
559  * Add a new rule
560  * @arg sk		Netlink socket.
561  * @arg tmpl		template with requested changes
562  * @arg flags		additional netlink message flags
563  *
564  * Builds a netlink message by calling rtnl_rule_build_add_request(),
565  * sends the request to the kernel and waits for the next ACK to be
566  * received and thus blocks until the request has been fullfilled.
567  *
568  * @return 0 on success or a negative error if an error occured.
569  */
rtnl_rule_add(struct nl_sock * sk,struct rtnl_rule * tmpl,int flags)570 int rtnl_rule_add(struct nl_sock *sk, struct rtnl_rule *tmpl, int flags)
571 {
572 	struct nl_msg *msg;
573 	int err;
574 
575 	if ((err = rtnl_rule_build_add_request(tmpl, flags, &msg)) < 0)
576 		return err;
577 
578 	err = nl_send_auto_complete(sk, msg);
579 	nlmsg_free(msg);
580 	if (err < 0)
581 		return err;
582 
583 	return wait_for_ack(sk);
584 }
585 
586 /** @} */
587 
588 /**
589  * @name Rule Deletion
590  * @{
591  */
592 
593 /**
594  * Build a netlink request message to delete a rule
595  * @arg rule		rule to delete
596  * @arg flags		additional netlink message flags
597  * @arg result		Result pointer
598  *
599  * Builds a new netlink message requesting a deletion of a rule.
600  * The netlink message header isn't fully equipped with all relevant
601  * fields and must thus be sent out via nl_send_auto_complete()
602  * or supplemented as needed. \a rule must point to an existing
603  * address.
604  *
605  * @return 0 on success or a negative error code.
606  */
rtnl_rule_build_delete_request(struct rtnl_rule * rule,int flags,struct nl_msg ** result)607 int rtnl_rule_build_delete_request(struct rtnl_rule *rule, int flags,
608 				   struct nl_msg **result)
609 {
610 	return build_rule_msg(rule, RTM_DELRULE, flags, result);
611 }
612 
613 /**
614  * Delete a rule
615  * @arg sk		Netlink socket.
616  * @arg rule		rule to delete
617  * @arg flags		additional netlink message flags
618  *
619  * Builds a netlink message by calling rtnl_rule_build_delete_request(),
620  * sends the request to the kernel and waits for the next ACK to be
621  * received and thus blocks until the request has been fullfilled.
622  *
623  * @return 0 on success or a negative error if an error occured.
624  */
rtnl_rule_delete(struct nl_sock * sk,struct rtnl_rule * rule,int flags)625 int rtnl_rule_delete(struct nl_sock *sk, struct rtnl_rule *rule, int flags)
626 {
627 	struct nl_msg *msg;
628 	int err;
629 
630 	if ((err = rtnl_rule_build_delete_request(rule, flags, &msg)) < 0)
631 		return err;
632 
633 	err = nl_send_auto_complete(sk, msg);
634 	nlmsg_free(msg);
635 	if (err < 0)
636 		return err;
637 
638 	return wait_for_ack(sk);
639 }
640 
641 /** @} */
642 
643 /**
644  * @name Attribute Modification
645  * @{
646  */
647 
rtnl_rule_set_family(struct rtnl_rule * rule,int family)648 void rtnl_rule_set_family(struct rtnl_rule *rule, int family)
649 {
650 	rule->r_family = family;
651 	rule->ce_mask |= RULE_ATTR_FAMILY;
652 }
653 
rtnl_rule_get_family(struct rtnl_rule * rule)654 int rtnl_rule_get_family(struct rtnl_rule *rule)
655 {
656 	if (rule->ce_mask & RULE_ATTR_FAMILY)
657 		return rule->r_family;
658 	else
659 		return AF_UNSPEC;
660 }
661 
rtnl_rule_set_prio(struct rtnl_rule * rule,uint32_t prio)662 void rtnl_rule_set_prio(struct rtnl_rule *rule, uint32_t prio)
663 {
664 	rule->r_prio = prio;
665 	rule->ce_mask |= RULE_ATTR_PRIO;
666 }
667 
rtnl_rule_get_prio(struct rtnl_rule * rule)668 uint32_t rtnl_rule_get_prio(struct rtnl_rule *rule)
669 {
670 	return rule->r_prio;
671 }
672 
rtnl_rule_set_mark(struct rtnl_rule * rule,uint32_t mark)673 void rtnl_rule_set_mark(struct rtnl_rule *rule, uint32_t mark)
674 {
675 	rule->r_mark = mark;
676 	rule->ce_mask |= RULE_ATTR_MARK;
677 }
678 
rtnl_rule_get_mark(struct rtnl_rule * rule)679 uint32_t rtnl_rule_get_mark(struct rtnl_rule *rule)
680 {
681 	return rule->r_mark;
682 }
683 
rtnl_rule_set_mask(struct rtnl_rule * rule,uint32_t mask)684 void rtnl_rule_set_mask(struct rtnl_rule *rule, uint32_t mask)
685 {
686 	rule->r_mask = mask;
687 	rule->ce_mask |= RULE_ATTR_MASK;
688 }
689 
rtnl_rule_get_mask(struct rtnl_rule * rule)690 uint32_t rtnl_rule_get_mask(struct rtnl_rule *rule)
691 {
692 	return rule->r_mask;
693 }
694 
rtnl_rule_set_table(struct rtnl_rule * rule,uint32_t table)695 void rtnl_rule_set_table(struct rtnl_rule *rule, uint32_t table)
696 {
697 	rule->r_table = table;
698 	rule->ce_mask |= RULE_ATTR_TABLE;
699 }
700 
rtnl_rule_get_table(struct rtnl_rule * rule)701 uint32_t rtnl_rule_get_table(struct rtnl_rule *rule)
702 {
703 	return rule->r_table;
704 }
705 
rtnl_rule_set_dsfield(struct rtnl_rule * rule,uint8_t dsfield)706 void rtnl_rule_set_dsfield(struct rtnl_rule *rule, uint8_t dsfield)
707 {
708 	rule->r_dsfield = dsfield;
709 	rule->ce_mask |= RULE_ATTR_DSFIELD;
710 }
711 
rtnl_rule_get_dsfield(struct rtnl_rule * rule)712 uint8_t rtnl_rule_get_dsfield(struct rtnl_rule *rule)
713 {
714 	return rule->r_dsfield;
715 }
716 
__assign_addr(struct rtnl_rule * rule,struct nl_addr ** pos,struct nl_addr * new,int flag)717 static inline int __assign_addr(struct rtnl_rule *rule, struct nl_addr **pos,
718 			        struct nl_addr *new, int flag)
719 {
720 	if (rule->ce_mask & RULE_ATTR_FAMILY) {
721 		if (new->a_family != rule->r_family)
722 			return -NLE_AF_MISMATCH;
723 	} else
724 		rule->r_family = new->a_family;
725 
726 	if (*pos)
727 		nl_addr_put(*pos);
728 
729 	nl_addr_get(new);
730 	*pos = new;
731 
732 	rule->ce_mask |= (flag | RULE_ATTR_FAMILY);
733 
734 	return 0;
735 }
736 
rtnl_rule_set_src(struct rtnl_rule * rule,struct nl_addr * src)737 int rtnl_rule_set_src(struct rtnl_rule *rule, struct nl_addr *src)
738 {
739 	return __assign_addr(rule, &rule->r_src, src, RULE_ATTR_SRC);
740 }
741 
rtnl_rule_get_src(struct rtnl_rule * rule)742 struct nl_addr *rtnl_rule_get_src(struct rtnl_rule *rule)
743 {
744 	return rule->r_src;
745 }
746 
rtnl_rule_set_dst(struct rtnl_rule * rule,struct nl_addr * dst)747 int rtnl_rule_set_dst(struct rtnl_rule *rule, struct nl_addr *dst)
748 {
749 	return __assign_addr(rule, &rule->r_dst, dst, RULE_ATTR_DST);
750 }
751 
rtnl_rule_get_dst(struct rtnl_rule * rule)752 struct nl_addr *rtnl_rule_get_dst(struct rtnl_rule *rule)
753 {
754 	return rule->r_dst;
755 }
756 
rtnl_rule_set_iif(struct rtnl_rule * rule,const char * dev)757 int rtnl_rule_set_iif(struct rtnl_rule *rule, const char *dev)
758 {
759 	if (strlen(dev) > IFNAMSIZ-1)
760 		return -NLE_RANGE;
761 
762 	strcpy(rule->r_iifname, dev);
763 	rule->ce_mask |= RULE_ATTR_IIFNAME;
764 	return 0;
765 }
766 
rtnl_rule_get_iif(struct rtnl_rule * rule)767 char *rtnl_rule_get_iif(struct rtnl_rule *rule)
768 {
769 	if (rule->ce_mask & RULE_ATTR_IIFNAME)
770 		return rule->r_iifname;
771 	else
772 		return NULL;
773 }
774 
rtnl_rule_set_oif(struct rtnl_rule * rule,const char * dev)775 int rtnl_rule_set_oif(struct rtnl_rule *rule, const char *dev)
776 {
777 	if (strlen(dev) > IFNAMSIZ-1)
778 		return -NLE_RANGE;
779 
780 	strcpy(rule->r_oifname, dev);
781 	rule->ce_mask |= RULE_ATTR_OIFNAME;
782 	return 0;
783 }
784 
rtnl_rule_get_oif(struct rtnl_rule * rule)785 char *rtnl_rule_get_oif(struct rtnl_rule *rule)
786 {
787 	if (rule->ce_mask & RULE_ATTR_OIFNAME)
788 		return rule->r_oifname;
789 	else
790 		return NULL;
791 }
792 
rtnl_rule_set_action(struct rtnl_rule * rule,uint8_t action)793 void rtnl_rule_set_action(struct rtnl_rule *rule, uint8_t action)
794 {
795 	rule->r_action = action;
796 	rule->ce_mask |= RULE_ATTR_ACTION;
797 }
798 
rtnl_rule_get_action(struct rtnl_rule * rule)799 uint8_t rtnl_rule_get_action(struct rtnl_rule *rule)
800 {
801 	return rule->r_action;
802 }
803 
804 /**
805  * Set l3mdev value of the rule (FRA_L3MDEV)
806  * @arg rule		rule
807  * @arg value		value to set
808  *
809  * Set the l3mdev value to value. Currently supported values
810  * are only 1 (set it) and -1 (unset it). All other values
811  * are reserved.
812  */
rtnl_rule_set_l3mdev(struct rtnl_rule * rule,int value)813 void rtnl_rule_set_l3mdev(struct rtnl_rule *rule, int value)
814 {
815 	if (value >= 0) {
816 		rule->r_l3mdev = (uint8_t) value;
817 		rule->ce_mask |= RULE_ATTR_L3MDEV;
818 	} else {
819 		rule->r_l3mdev = 0;
820 		rule->ce_mask &= ~((uint32_t) RULE_ATTR_L3MDEV);
821 	}
822 }
823 
824 /**
825  * Get l3mdev value of the rule (FRA_L3MDEV)
826  * @arg rule		rule
827  *
828  * @return a negative error code, including -NLE_MISSING_ATTR
829  *   if the property is unset. Otherwise returns a non-negative
830  *   value. As FRA_L3MDEV is a boolean, the only expected
831  *   value at the moment is 1.
832  */
rtnl_rule_get_l3mdev(struct rtnl_rule * rule)833 int rtnl_rule_get_l3mdev(struct rtnl_rule *rule)
834 {
835 	if (!rule)
836 		return -NLE_INVAL;
837 	if (!(rule->ce_mask & RULE_ATTR_L3MDEV))
838 		return -NLE_MISSING_ATTR;
839 	return rule->r_l3mdev;
840 }
841 
rtnl_rule_set_protocol(struct rtnl_rule * rule,uint8_t protocol)842 int rtnl_rule_set_protocol(struct rtnl_rule *rule, uint8_t protocol)
843 {
844 	if (protocol) {
845 		rule->r_protocol = protocol;
846 		rule->ce_mask |= RULE_ATTR_PROTOCOL;
847 	} else {
848 		rule->r_protocol = 0;
849 		rule->ce_mask &= ~((uint32_t) RULE_ATTR_PROTOCOL);
850 	}
851 	return 0;
852 }
853 
rtnl_rule_get_protocol(struct rtnl_rule * rule,uint8_t * protocol)854 int rtnl_rule_get_protocol(struct rtnl_rule *rule, uint8_t *protocol)
855 {
856 	if (!(rule->ce_mask & RULE_ATTR_PROTOCOL))
857 		return -NLE_INVAL;
858 
859 	*protocol = rule->r_protocol;
860 	return 0;
861 }
862 
rtnl_rule_set_ipproto(struct rtnl_rule * rule,uint8_t ip_proto)863 int rtnl_rule_set_ipproto(struct rtnl_rule *rule, uint8_t ip_proto)
864 {
865 	if (ip_proto) {
866 		rule->r_ip_proto = ip_proto;
867 		rule->ce_mask |= RULE_ATTR_IP_PROTO;
868 	} else {
869 		rule->r_ip_proto = 0;
870 		rule->ce_mask &= ~((uint32_t) RULE_ATTR_IP_PROTO);
871 	}
872 	return 0;
873 }
874 
rtnl_rule_get_ipproto(struct rtnl_rule * rule,uint8_t * ip_proto)875 int rtnl_rule_get_ipproto(struct rtnl_rule *rule, uint8_t *ip_proto)
876 {
877 	if (!(rule->ce_mask & RULE_ATTR_IP_PROTO))
878 		return -NLE_INVAL;
879 
880 	*ip_proto = rule->r_ip_proto;
881 	return 0;
882 }
883 
__rtnl_rule_set_port(struct fib_rule_port_range * prange,uint16_t start,uint16_t end,uint64_t attr,uint64_t * mask)884 static int __rtnl_rule_set_port(struct fib_rule_port_range *prange,
885 				uint16_t start, uint16_t end,
886 				uint64_t attr, uint64_t *mask)
887 {
888 	if ((start && end < start) || (end && !start))
889 		return -NLE_INVAL;
890 
891 	if (start) {
892 		prange->start = start;
893 		prange->end = end;
894 		*mask |= attr;
895 	} else {
896 		prange->start = 0;
897 		prange->end = 0;
898 		*mask &= ~attr;
899 
900 	}
901 	return 0;
902 }
903 
rtnl_rule_set_sport(struct rtnl_rule * rule,uint16_t sport)904 int rtnl_rule_set_sport(struct rtnl_rule *rule, uint16_t sport)
905 {
906 	return __rtnl_rule_set_port(&rule->r_sport, sport, sport,
907 				    RULE_ATTR_SPORT, &rule->ce_mask);
908 }
909 
rtnl_rule_set_sport_range(struct rtnl_rule * rule,uint16_t start,uint16_t end)910 int rtnl_rule_set_sport_range(struct rtnl_rule *rule, uint16_t start,
911 			      uint16_t end)
912 {
913 	return __rtnl_rule_set_port(&rule->r_sport, start, end,
914 				    RULE_ATTR_SPORT, &rule->ce_mask);
915 }
916 
rtnl_rule_get_sport(struct rtnl_rule * rule,uint16_t * start,uint16_t * end)917 int rtnl_rule_get_sport(struct rtnl_rule *rule, uint16_t *start, uint16_t *end)
918 {
919 	if (!(rule->ce_mask & RULE_ATTR_SPORT))
920 		return -NLE_INVAL;
921 
922 	*start = rule->r_sport.start;
923 	*end = rule->r_sport.end;
924 	return 0;
925 }
926 
rtnl_rule_set_dport(struct rtnl_rule * rule,uint16_t dport)927 int rtnl_rule_set_dport(struct rtnl_rule *rule, uint16_t dport)
928 {
929 	return __rtnl_rule_set_port(&rule->r_dport, dport, dport,
930 				    RULE_ATTR_DPORT, &rule->ce_mask);
931 }
932 
rtnl_rule_set_dport_range(struct rtnl_rule * rule,uint16_t start,uint16_t end)933 int rtnl_rule_set_dport_range(struct rtnl_rule *rule, uint16_t start,
934 			      uint16_t end)
935 {
936 	return __rtnl_rule_set_port(&rule->r_dport, start, end,
937 				    RULE_ATTR_DPORT, &rule->ce_mask);
938 }
939 
rtnl_rule_get_dport(struct rtnl_rule * rule,uint16_t * start,uint16_t * end)940 int rtnl_rule_get_dport(struct rtnl_rule *rule, uint16_t *start, uint16_t *end)
941 {
942 	if (!(rule->ce_mask & RULE_ATTR_DPORT))
943 		return -NLE_INVAL;
944 
945 	*start = rule->r_dport.start;
946 	*end = rule->r_dport.end;
947 	return 0;
948 }
949 
rtnl_rule_set_realms(struct rtnl_rule * rule,uint32_t realms)950 void rtnl_rule_set_realms(struct rtnl_rule *rule, uint32_t realms)
951 {
952 	rule->r_flow = realms;
953 	rule->ce_mask |= RULE_ATTR_FLOW;
954 }
955 
rtnl_rule_get_realms(struct rtnl_rule * rule)956 uint32_t rtnl_rule_get_realms(struct rtnl_rule *rule)
957 {
958 	return rule->r_flow;
959 }
960 
rtnl_rule_set_goto(struct rtnl_rule * rule,uint32_t ref)961 void rtnl_rule_set_goto(struct rtnl_rule *rule, uint32_t ref)
962 {
963 	rule->r_goto = ref;
964 	rule->ce_mask |= RULE_ATTR_GOTO;
965 }
966 
rtnl_rule_get_goto(struct rtnl_rule * rule)967 uint32_t rtnl_rule_get_goto(struct rtnl_rule *rule)
968 {
969 	return rule->r_goto;
970 }
971 
972 /** @} */
973 
974 static struct nl_object_ops rule_obj_ops = {
975 	.oo_name		= "route/rule",
976 	.oo_size		= sizeof(struct rtnl_rule),
977 	.oo_free_data		= rule_free_data,
978 	.oo_clone		= rule_clone,
979 	.oo_dump = {
980 	    [NL_DUMP_LINE]	= rule_dump_line,
981 	    [NL_DUMP_DETAILS]	= rule_dump_details,
982 	    [NL_DUMP_STATS]	= rule_dump_stats,
983 	},
984 	.oo_compare		= rule_compare,
985 	.oo_attrs2str		= rule_attrs2str,
986 	.oo_id_attrs		= ~0,
987 };
988 
989 static struct nl_af_group rule_groups[] = {
990 	{ AF_INET,	RTNLGRP_IPV4_RULE },
991 	{ AF_INET6,	RTNLGRP_IPV6_RULE },
992 	{ END_OF_GROUP_LIST },
993 };
994 
995 static struct nl_cache_ops rtnl_rule_ops = {
996 	.co_name		= "route/rule",
997 	.co_hdrsize		= sizeof(struct fib_rule_hdr),
998 	.co_msgtypes		= {
999 					{ RTM_NEWRULE, NL_ACT_NEW, "new" },
1000 					{ RTM_DELRULE, NL_ACT_DEL, "del" },
1001 					{ RTM_GETRULE, NL_ACT_GET, "get" },
1002 					END_OF_MSGTYPES_LIST,
1003 				  },
1004 	.co_protocol		= NETLINK_ROUTE,
1005 	.co_request_update	= rule_request_update,
1006 	.co_msg_parser		= rule_msg_parser,
1007 	.co_obj_ops		= &rule_obj_ops,
1008 	.co_groups		= rule_groups,
1009 };
1010 
rule_init(void)1011 static void _nl_init rule_init(void)
1012 {
1013 	nl_cache_mngt_register(&rtnl_rule_ops);
1014 }
1015 
rule_exit(void)1016 static void _nl_exit rule_exit(void)
1017 {
1018 	nl_cache_mngt_unregister(&rtnl_rule_ops);
1019 }
1020 
1021 /** @} */
1022