xref: /openbmc/linux/net/mptcp/pm_userspace.c (revision e8254a8e)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Multipath TCP
3  *
4  * Copyright (c) 2022, Intel Corporation.
5  */
6 
7 #include "protocol.h"
8 #include "mib.h"
9 
10 void mptcp_free_local_addr_list(struct mptcp_sock *msk)
11 {
12 	struct mptcp_pm_addr_entry *entry, *tmp;
13 	struct sock *sk = (struct sock *)msk;
14 	LIST_HEAD(free_list);
15 
16 	if (!mptcp_pm_is_userspace(msk))
17 		return;
18 
19 	spin_lock_bh(&msk->pm.lock);
20 	list_splice_init(&msk->pm.userspace_pm_local_addr_list, &free_list);
21 	spin_unlock_bh(&msk->pm.lock);
22 
23 	list_for_each_entry_safe(entry, tmp, &free_list, list) {
24 		sock_kfree_s(sk, entry, sizeof(*entry));
25 	}
26 }
27 
28 int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
29 					     struct mptcp_pm_addr_entry *entry)
30 {
31 	DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
32 	struct mptcp_pm_addr_entry *match = NULL;
33 	struct sock *sk = (struct sock *)msk;
34 	struct mptcp_pm_addr_entry *e;
35 	bool addr_match = false;
36 	bool id_match = false;
37 	int ret = -EINVAL;
38 
39 	bitmap_zero(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
40 
41 	spin_lock_bh(&msk->pm.lock);
42 	list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) {
43 		addr_match = mptcp_addresses_equal(&e->addr, &entry->addr, true);
44 		if (addr_match && entry->addr.id == 0)
45 			entry->addr.id = e->addr.id;
46 		id_match = (e->addr.id == entry->addr.id);
47 		if (addr_match && id_match) {
48 			match = e;
49 			break;
50 		} else if (addr_match || id_match) {
51 			break;
52 		}
53 		__set_bit(e->addr.id, id_bitmap);
54 	}
55 
56 	if (!match && !addr_match && !id_match) {
57 		/* Memory for the entry is allocated from the
58 		 * sock option buffer.
59 		 */
60 		e = sock_kmalloc(sk, sizeof(*e), GFP_ATOMIC);
61 		if (!e) {
62 			spin_unlock_bh(&msk->pm.lock);
63 			return -ENOMEM;
64 		}
65 
66 		*e = *entry;
67 		if (!e->addr.id)
68 			e->addr.id = find_next_zero_bit(id_bitmap,
69 							MPTCP_PM_MAX_ADDR_ID + 1,
70 							1);
71 		list_add_tail_rcu(&e->list, &msk->pm.userspace_pm_local_addr_list);
72 		ret = e->addr.id;
73 	} else if (match) {
74 		ret = entry->addr.id;
75 	}
76 
77 	spin_unlock_bh(&msk->pm.lock);
78 	return ret;
79 }
80 
81 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
82 						   unsigned int id,
83 						   u8 *flags, int *ifindex)
84 {
85 	struct mptcp_pm_addr_entry *entry, *match = NULL;
86 
87 	*flags = 0;
88 	*ifindex = 0;
89 
90 	spin_lock_bh(&msk->pm.lock);
91 	list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
92 		if (id == entry->addr.id) {
93 			match = entry;
94 			break;
95 		}
96 	}
97 	spin_unlock_bh(&msk->pm.lock);
98 	if (match) {
99 		*flags = match->flags;
100 		*ifindex = match->ifindex;
101 	}
102 
103 	return 0;
104 }
105 
106 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk,
107 				    struct mptcp_addr_info *skc)
108 {
109 	struct mptcp_pm_addr_entry new_entry;
110 	__be16 msk_sport =  ((struct inet_sock *)
111 			     inet_sk((struct sock *)msk))->inet_sport;
112 
113 	memset(&new_entry, 0, sizeof(struct mptcp_pm_addr_entry));
114 	new_entry.addr = *skc;
115 	new_entry.addr.id = 0;
116 	new_entry.flags = MPTCP_PM_ADDR_FLAG_IMPLICIT;
117 
118 	if (new_entry.addr.port == msk_sport)
119 		new_entry.addr.port = 0;
120 
121 	return mptcp_userspace_pm_append_new_local_addr(msk, &new_entry);
122 }
123 
124 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info)
125 {
126 	struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
127 	struct nlattr *addr = info->attrs[MPTCP_PM_ATTR_ADDR];
128 	struct mptcp_pm_addr_entry addr_val;
129 	struct mptcp_sock *msk;
130 	int err = -EINVAL;
131 	u32 token_val;
132 
133 	if (!addr || !token) {
134 		GENL_SET_ERR_MSG(info, "missing required inputs");
135 		return err;
136 	}
137 
138 	token_val = nla_get_u32(token);
139 
140 	msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
141 	if (!msk) {
142 		NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
143 		return err;
144 	}
145 
146 	if (!mptcp_pm_is_userspace(msk)) {
147 		GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
148 		goto announce_err;
149 	}
150 
151 	err = mptcp_pm_parse_entry(addr, info, true, &addr_val);
152 	if (err < 0) {
153 		GENL_SET_ERR_MSG(info, "error parsing local address");
154 		goto announce_err;
155 	}
156 
157 	if (addr_val.addr.id == 0 || !(addr_val.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
158 		GENL_SET_ERR_MSG(info, "invalid addr id or flags");
159 		err = -EINVAL;
160 		goto announce_err;
161 	}
162 
163 	err = mptcp_userspace_pm_append_new_local_addr(msk, &addr_val);
164 	if (err < 0) {
165 		GENL_SET_ERR_MSG(info, "did not match address and id");
166 		goto announce_err;
167 	}
168 
169 	lock_sock((struct sock *)msk);
170 	spin_lock_bh(&msk->pm.lock);
171 
172 	if (mptcp_pm_alloc_anno_list(msk, &addr_val)) {
173 		mptcp_pm_announce_addr(msk, &addr_val.addr, false);
174 		mptcp_pm_nl_addr_send_ack(msk);
175 	}
176 
177 	spin_unlock_bh(&msk->pm.lock);
178 	release_sock((struct sock *)msk);
179 
180 	err = 0;
181  announce_err:
182 	sock_put((struct sock *)msk);
183 	return err;
184 }
185 
186 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info)
187 {
188 	struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
189 	struct nlattr *id = info->attrs[MPTCP_PM_ATTR_LOC_ID];
190 	struct mptcp_pm_addr_entry *match = NULL;
191 	struct mptcp_pm_addr_entry *entry;
192 	struct mptcp_sock *msk;
193 	LIST_HEAD(free_list);
194 	int err = -EINVAL;
195 	u32 token_val;
196 	u8 id_val;
197 
198 	if (!id || !token) {
199 		GENL_SET_ERR_MSG(info, "missing required inputs");
200 		return err;
201 	}
202 
203 	id_val = nla_get_u8(id);
204 	token_val = nla_get_u32(token);
205 
206 	msk = mptcp_token_get_sock(sock_net(skb->sk), token_val);
207 	if (!msk) {
208 		NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
209 		return err;
210 	}
211 
212 	if (!mptcp_pm_is_userspace(msk)) {
213 		GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
214 		goto remove_err;
215 	}
216 
217 	lock_sock((struct sock *)msk);
218 
219 	list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
220 		if (entry->addr.id == id_val) {
221 			match = entry;
222 			break;
223 		}
224 	}
225 
226 	if (!match) {
227 		GENL_SET_ERR_MSG(info, "address with specified id not found");
228 		release_sock((struct sock *)msk);
229 		goto remove_err;
230 	}
231 
232 	list_move(&match->list, &free_list);
233 
234 	mptcp_pm_remove_addrs_and_subflows(msk, &free_list);
235 
236 	release_sock((struct sock *)msk);
237 
238 	list_for_each_entry_safe(match, entry, &free_list, list) {
239 		sock_kfree_s((struct sock *)msk, match, sizeof(*match));
240 	}
241 
242 	err = 0;
243  remove_err:
244 	sock_put((struct sock *)msk);
245 	return err;
246 }
247 
248 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info)
249 {
250 	struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
251 	struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
252 	struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR];
253 	struct mptcp_addr_info addr_r;
254 	struct mptcp_addr_info addr_l;
255 	struct mptcp_sock *msk;
256 	int err = -EINVAL;
257 	struct sock *sk;
258 	u32 token_val;
259 
260 	if (!laddr || !raddr || !token) {
261 		GENL_SET_ERR_MSG(info, "missing required inputs");
262 		return err;
263 	}
264 
265 	token_val = nla_get_u32(token);
266 
267 	msk = mptcp_token_get_sock(genl_info_net(info), token_val);
268 	if (!msk) {
269 		NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
270 		return err;
271 	}
272 
273 	if (!mptcp_pm_is_userspace(msk)) {
274 		GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
275 		goto create_err;
276 	}
277 
278 	err = mptcp_pm_parse_addr(laddr, info, &addr_l);
279 	if (err < 0) {
280 		NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr");
281 		goto create_err;
282 	}
283 
284 	if (addr_l.id == 0) {
285 		NL_SET_ERR_MSG_ATTR(info->extack, laddr, "missing local addr id");
286 		err = -EINVAL;
287 		goto create_err;
288 	}
289 
290 	err = mptcp_pm_parse_addr(raddr, info, &addr_r);
291 	if (err < 0) {
292 		NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr");
293 		goto create_err;
294 	}
295 
296 	sk = (struct sock *)msk;
297 	lock_sock(sk);
298 
299 	err = __mptcp_subflow_connect(sk, &addr_l, &addr_r);
300 
301 	release_sock(sk);
302 
303  create_err:
304 	sock_put((struct sock *)msk);
305 	return err;
306 }
307 
308 static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk,
309 				      const struct mptcp_addr_info *local,
310 				      const struct mptcp_addr_info *remote)
311 {
312 	struct mptcp_subflow_context *subflow;
313 
314 	if (local->family != remote->family)
315 		return NULL;
316 
317 	mptcp_for_each_subflow(msk, subflow) {
318 		const struct inet_sock *issk;
319 		struct sock *ssk;
320 
321 		ssk = mptcp_subflow_tcp_sock(subflow);
322 
323 		if (local->family != ssk->sk_family)
324 			continue;
325 
326 		issk = inet_sk(ssk);
327 
328 		switch (ssk->sk_family) {
329 		case AF_INET:
330 			if (issk->inet_saddr != local->addr.s_addr ||
331 			    issk->inet_daddr != remote->addr.s_addr)
332 				continue;
333 			break;
334 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
335 		case AF_INET6: {
336 			const struct ipv6_pinfo *pinfo = inet6_sk(ssk);
337 
338 			if (!ipv6_addr_equal(&local->addr6, &pinfo->saddr) ||
339 			    !ipv6_addr_equal(&remote->addr6, &ssk->sk_v6_daddr))
340 				continue;
341 			break;
342 		}
343 #endif
344 		default:
345 			continue;
346 		}
347 
348 		if (issk->inet_sport == local->port &&
349 		    issk->inet_dport == remote->port)
350 			return ssk;
351 	}
352 
353 	return NULL;
354 }
355 
356 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info)
357 {
358 	struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
359 	struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
360 	struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR];
361 	struct mptcp_addr_info addr_l;
362 	struct mptcp_addr_info addr_r;
363 	struct mptcp_sock *msk;
364 	struct sock *sk, *ssk;
365 	int err = -EINVAL;
366 	u32 token_val;
367 
368 	if (!laddr || !raddr || !token) {
369 		GENL_SET_ERR_MSG(info, "missing required inputs");
370 		return err;
371 	}
372 
373 	token_val = nla_get_u32(token);
374 
375 	msk = mptcp_token_get_sock(genl_info_net(info), token_val);
376 	if (!msk) {
377 		NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token");
378 		return err;
379 	}
380 
381 	if (!mptcp_pm_is_userspace(msk)) {
382 		GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected");
383 		goto destroy_err;
384 	}
385 
386 	err = mptcp_pm_parse_addr(laddr, info, &addr_l);
387 	if (err < 0) {
388 		NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr");
389 		goto destroy_err;
390 	}
391 
392 	err = mptcp_pm_parse_addr(raddr, info, &addr_r);
393 	if (err < 0) {
394 		NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr");
395 		goto destroy_err;
396 	}
397 
398 	if (addr_l.family != addr_r.family) {
399 		GENL_SET_ERR_MSG(info, "address families do not match");
400 		err = -EINVAL;
401 		goto destroy_err;
402 	}
403 
404 	if (!addr_l.port || !addr_r.port) {
405 		GENL_SET_ERR_MSG(info, "missing local or remote port");
406 		err = -EINVAL;
407 		goto destroy_err;
408 	}
409 
410 	sk = (struct sock *)msk;
411 	lock_sock(sk);
412 	ssk = mptcp_nl_find_ssk(msk, &addr_l, &addr_r);
413 	if (ssk) {
414 		struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
415 
416 		mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
417 		mptcp_close_ssk(sk, ssk, subflow);
418 		MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW);
419 		err = 0;
420 	} else {
421 		err = -ESRCH;
422 	}
423 	release_sock(sk);
424 
425 destroy_err:
426 	sock_put((struct sock *)msk);
427 	return err;
428 }
429 
430 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token,
431 				 struct mptcp_pm_addr_entry *loc,
432 				 struct mptcp_pm_addr_entry *rem, u8 bkup)
433 {
434 	struct mptcp_sock *msk;
435 	int ret = -EINVAL;
436 	u32 token_val;
437 
438 	token_val = nla_get_u32(token);
439 
440 	msk = mptcp_token_get_sock(net, token_val);
441 	if (!msk)
442 		return ret;
443 
444 	if (!mptcp_pm_is_userspace(msk))
445 		goto set_flags_err;
446 
447 	if (loc->addr.family == AF_UNSPEC ||
448 	    rem->addr.family == AF_UNSPEC)
449 		goto set_flags_err;
450 
451 	lock_sock((struct sock *)msk);
452 	ret = mptcp_pm_nl_mp_prio_send_ack(msk, &loc->addr, &rem->addr, bkup);
453 	release_sock((struct sock *)msk);
454 
455 set_flags_err:
456 	sock_put((struct sock *)msk);
457 	return ret;
458 }
459