xref: /openbmc/linux/net/ceph/auth.c (revision f7af616c)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/ceph/ceph_debug.h>
3 
4 #include <linux/module.h>
5 #include <linux/err.h>
6 #include <linux/slab.h>
7 
8 #include <linux/ceph/types.h>
9 #include <linux/ceph/decode.h>
10 #include <linux/ceph/libceph.h>
11 #include <linux/ceph/messenger.h>
12 #include "auth_none.h"
13 #include "auth_x.h"
14 
15 
16 /*
17  * get protocol handler
18  */
19 static u32 supported_protocols[] = {
20 	CEPH_AUTH_NONE,
21 	CEPH_AUTH_CEPHX
22 };
23 
24 static int init_protocol(struct ceph_auth_client *ac, int proto)
25 {
26 	dout("%s proto %d\n", __func__, proto);
27 
28 	switch (proto) {
29 	case CEPH_AUTH_NONE:
30 		return ceph_auth_none_init(ac);
31 	case CEPH_AUTH_CEPHX:
32 		return ceph_x_init(ac);
33 	default:
34 		pr_err("bad auth protocol %d\n", proto);
35 		return -EINVAL;
36 	}
37 }
38 
39 static void set_global_id(struct ceph_auth_client *ac, u64 global_id)
40 {
41 	dout("%s global_id %llu\n", __func__, global_id);
42 
43 	if (!global_id)
44 		pr_err("got zero global_id\n");
45 
46 	if (ac->global_id && global_id != ac->global_id)
47 		pr_err("global_id changed from %llu to %llu\n", ac->global_id,
48 		       global_id);
49 
50 	ac->global_id = global_id;
51 }
52 
53 /*
54  * setup, teardown.
55  */
56 struct ceph_auth_client *ceph_auth_init(const char *name,
57 					const struct ceph_crypto_key *key,
58 					const int *con_modes)
59 {
60 	struct ceph_auth_client *ac;
61 	int ret;
62 
63 	ret = -ENOMEM;
64 	ac = kzalloc(sizeof(*ac), GFP_NOFS);
65 	if (!ac)
66 		goto out;
67 
68 	mutex_init(&ac->mutex);
69 	ac->negotiating = true;
70 	if (name)
71 		ac->name = name;
72 	else
73 		ac->name = CEPH_AUTH_NAME_DEFAULT;
74 	ac->key = key;
75 	ac->preferred_mode = con_modes[0];
76 	ac->fallback_mode = con_modes[1];
77 
78 	dout("%s name '%s' preferred_mode %d fallback_mode %d\n", __func__,
79 	     ac->name, ac->preferred_mode, ac->fallback_mode);
80 	return ac;
81 
82 out:
83 	return ERR_PTR(ret);
84 }
85 
86 void ceph_auth_destroy(struct ceph_auth_client *ac)
87 {
88 	dout("auth_destroy %p\n", ac);
89 	if (ac->ops)
90 		ac->ops->destroy(ac);
91 	kfree(ac);
92 }
93 
94 /*
95  * Reset occurs when reconnecting to the monitor.
96  */
97 void ceph_auth_reset(struct ceph_auth_client *ac)
98 {
99 	mutex_lock(&ac->mutex);
100 	dout("auth_reset %p\n", ac);
101 	if (ac->ops && !ac->negotiating)
102 		ac->ops->reset(ac);
103 	ac->negotiating = true;
104 	mutex_unlock(&ac->mutex);
105 }
106 
107 /*
108  * EntityName, not to be confused with entity_name_t
109  */
110 int ceph_auth_entity_name_encode(const char *name, void **p, void *end)
111 {
112 	int len = strlen(name);
113 
114 	if (*p + 2*sizeof(u32) + len > end)
115 		return -ERANGE;
116 	ceph_encode_32(p, CEPH_ENTITY_TYPE_CLIENT);
117 	ceph_encode_32(p, len);
118 	ceph_encode_copy(p, name, len);
119 	return 0;
120 }
121 
122 /*
123  * Initiate protocol negotiation with monitor.  Include entity name
124  * and list supported protocols.
125  */
126 int ceph_auth_build_hello(struct ceph_auth_client *ac, void *buf, size_t len)
127 {
128 	struct ceph_mon_request_header *monhdr = buf;
129 	void *p = monhdr + 1, *end = buf + len, *lenp;
130 	int i, num;
131 	int ret;
132 
133 	mutex_lock(&ac->mutex);
134 	dout("auth_build_hello\n");
135 	monhdr->have_version = 0;
136 	monhdr->session_mon = cpu_to_le16(-1);
137 	monhdr->session_mon_tid = 0;
138 
139 	ceph_encode_32(&p, CEPH_AUTH_UNKNOWN);  /* no protocol, yet */
140 
141 	lenp = p;
142 	p += sizeof(u32);
143 
144 	ceph_decode_need(&p, end, 1 + sizeof(u32), bad);
145 	ceph_encode_8(&p, 1);
146 	num = ARRAY_SIZE(supported_protocols);
147 	ceph_encode_32(&p, num);
148 	ceph_decode_need(&p, end, num * sizeof(u32), bad);
149 	for (i = 0; i < num; i++)
150 		ceph_encode_32(&p, supported_protocols[i]);
151 
152 	ret = ceph_auth_entity_name_encode(ac->name, &p, end);
153 	if (ret < 0)
154 		goto out;
155 	ceph_decode_need(&p, end, sizeof(u64), bad);
156 	ceph_encode_64(&p, ac->global_id);
157 
158 	ceph_encode_32(&lenp, p - lenp - sizeof(u32));
159 	ret = p - buf;
160 out:
161 	mutex_unlock(&ac->mutex);
162 	return ret;
163 
164 bad:
165 	ret = -ERANGE;
166 	goto out;
167 }
168 
169 static int build_request(struct ceph_auth_client *ac, bool add_header,
170 			 void *buf, int buf_len)
171 {
172 	void *end = buf + buf_len;
173 	void *p;
174 	int ret;
175 
176 	p = buf;
177 	if (add_header) {
178 		/* struct ceph_mon_request_header + protocol */
179 		ceph_encode_64_safe(&p, end, 0, e_range);
180 		ceph_encode_16_safe(&p, end, -1, e_range);
181 		ceph_encode_64_safe(&p, end, 0, e_range);
182 		ceph_encode_32_safe(&p, end, ac->protocol, e_range);
183 	}
184 
185 	ceph_encode_need(&p, end, sizeof(u32), e_range);
186 	ret = ac->ops->build_request(ac, p + sizeof(u32), end);
187 	if (ret < 0) {
188 		pr_err("auth protocol '%s' building request failed: %d\n",
189 		       ceph_auth_proto_name(ac->protocol), ret);
190 		return ret;
191 	}
192 	dout(" built request %d bytes\n", ret);
193 	ceph_encode_32(&p, ret);
194 	return p + ret - buf;
195 
196 e_range:
197 	return -ERANGE;
198 }
199 
200 /*
201  * Handle auth message from monitor.
202  */
203 int ceph_handle_auth_reply(struct ceph_auth_client *ac,
204 			   void *buf, size_t len,
205 			   void *reply_buf, size_t reply_len)
206 {
207 	void *p = buf;
208 	void *end = buf + len;
209 	int protocol;
210 	s32 result;
211 	u64 global_id;
212 	void *payload, *payload_end;
213 	int payload_len;
214 	char *result_msg;
215 	int result_msg_len;
216 	int ret = -EINVAL;
217 
218 	mutex_lock(&ac->mutex);
219 	dout("handle_auth_reply %p %p\n", p, end);
220 	ceph_decode_need(&p, end, sizeof(u32) * 3 + sizeof(u64), bad);
221 	protocol = ceph_decode_32(&p);
222 	result = ceph_decode_32(&p);
223 	global_id = ceph_decode_64(&p);
224 	payload_len = ceph_decode_32(&p);
225 	payload = p;
226 	p += payload_len;
227 	ceph_decode_need(&p, end, sizeof(u32), bad);
228 	result_msg_len = ceph_decode_32(&p);
229 	result_msg = p;
230 	p += result_msg_len;
231 	if (p != end)
232 		goto bad;
233 
234 	dout(" result %d '%.*s' gid %llu len %d\n", result, result_msg_len,
235 	     result_msg, global_id, payload_len);
236 
237 	payload_end = payload + payload_len;
238 
239 	if (ac->negotiating) {
240 		/* server does not support our protocols? */
241 		if (!protocol && result < 0) {
242 			ret = result;
243 			goto out;
244 		}
245 		/* set up (new) protocol handler? */
246 		if (ac->protocol && ac->protocol != protocol) {
247 			ac->ops->destroy(ac);
248 			ac->protocol = 0;
249 			ac->ops = NULL;
250 		}
251 		if (ac->protocol != protocol) {
252 			ret = init_protocol(ac, protocol);
253 			if (ret) {
254 				pr_err("auth protocol '%s' init failed: %d\n",
255 				       ceph_auth_proto_name(protocol), ret);
256 				goto out;
257 			}
258 		}
259 
260 		ac->negotiating = false;
261 	}
262 
263 	ret = ac->ops->handle_reply(ac, result, payload, payload_end,
264 				    NULL, NULL, NULL, NULL);
265 	if (ret == -EAGAIN) {
266 		ret = build_request(ac, true, reply_buf, reply_len);
267 		goto out;
268 	} else if (ret) {
269 		pr_err("auth protocol '%s' mauth authentication failed: %d\n",
270 		       ceph_auth_proto_name(ac->protocol), result);
271 		goto out;
272 	}
273 
274 	set_global_id(ac, global_id);
275 
276 out:
277 	mutex_unlock(&ac->mutex);
278 	return ret;
279 
280 bad:
281 	pr_err("failed to decode auth msg\n");
282 	ret = -EINVAL;
283 	goto out;
284 }
285 
286 int ceph_build_auth(struct ceph_auth_client *ac,
287 		    void *msg_buf, size_t msg_len)
288 {
289 	int ret = 0;
290 
291 	mutex_lock(&ac->mutex);
292 	if (ac->ops->should_authenticate(ac))
293 		ret = build_request(ac, true, msg_buf, msg_len);
294 	mutex_unlock(&ac->mutex);
295 	return ret;
296 }
297 
298 int ceph_auth_is_authenticated(struct ceph_auth_client *ac)
299 {
300 	int ret = 0;
301 
302 	mutex_lock(&ac->mutex);
303 	if (ac->ops)
304 		ret = ac->ops->is_authenticated(ac);
305 	mutex_unlock(&ac->mutex);
306 	return ret;
307 }
308 EXPORT_SYMBOL(ceph_auth_is_authenticated);
309 
310 int __ceph_auth_get_authorizer(struct ceph_auth_client *ac,
311 			       struct ceph_auth_handshake *auth,
312 			       int peer_type, bool force_new,
313 			       int *proto, int *pref_mode, int *fallb_mode)
314 {
315 	int ret;
316 
317 	mutex_lock(&ac->mutex);
318 	if (force_new && auth->authorizer) {
319 		ceph_auth_destroy_authorizer(auth->authorizer);
320 		auth->authorizer = NULL;
321 	}
322 	if (!auth->authorizer)
323 		ret = ac->ops->create_authorizer(ac, peer_type, auth);
324 	else if (ac->ops->update_authorizer)
325 		ret = ac->ops->update_authorizer(ac, peer_type, auth);
326 	else
327 		ret = 0;
328 	if (ret)
329 		goto out;
330 
331 	*proto = ac->protocol;
332 	if (pref_mode && fallb_mode) {
333 		*pref_mode = ac->preferred_mode;
334 		*fallb_mode = ac->fallback_mode;
335 	}
336 
337 out:
338 	mutex_unlock(&ac->mutex);
339 	return ret;
340 }
341 EXPORT_SYMBOL(__ceph_auth_get_authorizer);
342 
343 void ceph_auth_destroy_authorizer(struct ceph_authorizer *a)
344 {
345 	a->destroy(a);
346 }
347 EXPORT_SYMBOL(ceph_auth_destroy_authorizer);
348 
349 int ceph_auth_add_authorizer_challenge(struct ceph_auth_client *ac,
350 				       struct ceph_authorizer *a,
351 				       void *challenge_buf,
352 				       int challenge_buf_len)
353 {
354 	int ret = 0;
355 
356 	mutex_lock(&ac->mutex);
357 	if (ac->ops && ac->ops->add_authorizer_challenge)
358 		ret = ac->ops->add_authorizer_challenge(ac, a, challenge_buf,
359 							challenge_buf_len);
360 	mutex_unlock(&ac->mutex);
361 	return ret;
362 }
363 EXPORT_SYMBOL(ceph_auth_add_authorizer_challenge);
364 
365 int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac,
366 				      struct ceph_authorizer *a,
367 				      void *reply, int reply_len,
368 				      u8 *session_key, int *session_key_len,
369 				      u8 *con_secret, int *con_secret_len)
370 {
371 	int ret = 0;
372 
373 	mutex_lock(&ac->mutex);
374 	if (ac->ops && ac->ops->verify_authorizer_reply)
375 		ret = ac->ops->verify_authorizer_reply(ac, a,
376 			reply, reply_len, session_key, session_key_len,
377 			con_secret, con_secret_len);
378 	mutex_unlock(&ac->mutex);
379 	return ret;
380 }
381 EXPORT_SYMBOL(ceph_auth_verify_authorizer_reply);
382 
383 void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac, int peer_type)
384 {
385 	mutex_lock(&ac->mutex);
386 	if (ac->ops && ac->ops->invalidate_authorizer)
387 		ac->ops->invalidate_authorizer(ac, peer_type);
388 	mutex_unlock(&ac->mutex);
389 }
390 EXPORT_SYMBOL(ceph_auth_invalidate_authorizer);
391 
392 /*
393  * msgr2 authentication
394  */
395 
396 static bool contains(const int *arr, int cnt, int val)
397 {
398 	int i;
399 
400 	for (i = 0; i < cnt; i++) {
401 		if (arr[i] == val)
402 			return true;
403 	}
404 
405 	return false;
406 }
407 
408 static int encode_con_modes(void **p, void *end, int pref_mode, int fallb_mode)
409 {
410 	WARN_ON(pref_mode == CEPH_CON_MODE_UNKNOWN);
411 	if (fallb_mode != CEPH_CON_MODE_UNKNOWN) {
412 		ceph_encode_32_safe(p, end, 2, e_range);
413 		ceph_encode_32_safe(p, end, pref_mode, e_range);
414 		ceph_encode_32_safe(p, end, fallb_mode, e_range);
415 	} else {
416 		ceph_encode_32_safe(p, end, 1, e_range);
417 		ceph_encode_32_safe(p, end, pref_mode, e_range);
418 	}
419 
420 	return 0;
421 
422 e_range:
423 	return -ERANGE;
424 }
425 
426 /*
427  * Similar to ceph_auth_build_hello().
428  */
429 int ceph_auth_get_request(struct ceph_auth_client *ac, void *buf, int buf_len)
430 {
431 	int proto = ac->key ? CEPH_AUTH_CEPHX : CEPH_AUTH_NONE;
432 	void *end = buf + buf_len;
433 	void *lenp;
434 	void *p;
435 	int ret;
436 
437 	mutex_lock(&ac->mutex);
438 	if (ac->protocol == CEPH_AUTH_UNKNOWN) {
439 		ret = init_protocol(ac, proto);
440 		if (ret) {
441 			pr_err("auth protocol '%s' init failed: %d\n",
442 			       ceph_auth_proto_name(proto), ret);
443 			goto out;
444 		}
445 	} else {
446 		WARN_ON(ac->protocol != proto);
447 		ac->ops->reset(ac);
448 	}
449 
450 	p = buf;
451 	ceph_encode_32_safe(&p, end, ac->protocol, e_range);
452 	ret = encode_con_modes(&p, end, ac->preferred_mode, ac->fallback_mode);
453 	if (ret)
454 		goto out;
455 
456 	lenp = p;
457 	p += 4;  /* space for len */
458 
459 	ceph_encode_8_safe(&p, end, CEPH_AUTH_MODE_MON, e_range);
460 	ret = ceph_auth_entity_name_encode(ac->name, &p, end);
461 	if (ret)
462 		goto out;
463 
464 	ceph_encode_64_safe(&p, end, ac->global_id, e_range);
465 	ceph_encode_32(&lenp, p - lenp - 4);
466 	ret = p - buf;
467 
468 out:
469 	mutex_unlock(&ac->mutex);
470 	return ret;
471 
472 e_range:
473 	ret = -ERANGE;
474 	goto out;
475 }
476 
477 int ceph_auth_handle_reply_more(struct ceph_auth_client *ac, void *reply,
478 				int reply_len, void *buf, int buf_len)
479 {
480 	int ret;
481 
482 	mutex_lock(&ac->mutex);
483 	ret = ac->ops->handle_reply(ac, 0, reply, reply + reply_len,
484 				    NULL, NULL, NULL, NULL);
485 	if (ret == -EAGAIN)
486 		ret = build_request(ac, false, buf, buf_len);
487 	else
488 		WARN_ON(ret >= 0);
489 	mutex_unlock(&ac->mutex);
490 	return ret;
491 }
492 
493 int ceph_auth_handle_reply_done(struct ceph_auth_client *ac,
494 				u64 global_id, void *reply, int reply_len,
495 				u8 *session_key, int *session_key_len,
496 				u8 *con_secret, int *con_secret_len)
497 {
498 	int ret;
499 
500 	mutex_lock(&ac->mutex);
501 	ret = ac->ops->handle_reply(ac, 0, reply, reply + reply_len,
502 				    session_key, session_key_len,
503 				    con_secret, con_secret_len);
504 	if (!ret)
505 		set_global_id(ac, global_id);
506 	mutex_unlock(&ac->mutex);
507 	return ret;
508 }
509 
510 bool ceph_auth_handle_bad_method(struct ceph_auth_client *ac,
511 				 int used_proto, int result,
512 				 const int *allowed_protos, int proto_cnt,
513 				 const int *allowed_modes, int mode_cnt)
514 {
515 	mutex_lock(&ac->mutex);
516 	WARN_ON(used_proto != ac->protocol);
517 
518 	if (result == -EOPNOTSUPP) {
519 		if (!contains(allowed_protos, proto_cnt, ac->protocol)) {
520 			pr_err("auth protocol '%s' not allowed\n",
521 			       ceph_auth_proto_name(ac->protocol));
522 			goto not_allowed;
523 		}
524 		if (!contains(allowed_modes, mode_cnt, ac->preferred_mode) &&
525 		    (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN ||
526 		     !contains(allowed_modes, mode_cnt, ac->fallback_mode))) {
527 			pr_err("preferred mode '%s' not allowed\n",
528 			       ceph_con_mode_name(ac->preferred_mode));
529 			if (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN)
530 				pr_err("no fallback mode\n");
531 			else
532 				pr_err("fallback mode '%s' not allowed\n",
533 				       ceph_con_mode_name(ac->fallback_mode));
534 			goto not_allowed;
535 		}
536 	}
537 
538 	WARN_ON(result == -EOPNOTSUPP || result >= 0);
539 	pr_err("auth protocol '%s' msgr authentication failed: %d\n",
540 	       ceph_auth_proto_name(ac->protocol), result);
541 
542 	mutex_unlock(&ac->mutex);
543 	return true;
544 
545 not_allowed:
546 	mutex_unlock(&ac->mutex);
547 	return false;
548 }
549 
550 int ceph_auth_get_authorizer(struct ceph_auth_client *ac,
551 			     struct ceph_auth_handshake *auth,
552 			     int peer_type, void *buf, int *buf_len)
553 {
554 	void *end = buf + *buf_len;
555 	int pref_mode, fallb_mode;
556 	int proto;
557 	void *p;
558 	int ret;
559 
560 	ret = __ceph_auth_get_authorizer(ac, auth, peer_type, true, &proto,
561 					 &pref_mode, &fallb_mode);
562 	if (ret)
563 		return ret;
564 
565 	p = buf;
566 	ceph_encode_32_safe(&p, end, proto, e_range);
567 	ret = encode_con_modes(&p, end, pref_mode, fallb_mode);
568 	if (ret)
569 		return ret;
570 
571 	ceph_encode_32_safe(&p, end, auth->authorizer_buf_len, e_range);
572 	*buf_len = p - buf;
573 	return 0;
574 
575 e_range:
576 	return -ERANGE;
577 }
578 EXPORT_SYMBOL(ceph_auth_get_authorizer);
579 
580 int ceph_auth_handle_svc_reply_more(struct ceph_auth_client *ac,
581 				    struct ceph_auth_handshake *auth,
582 				    void *reply, int reply_len,
583 				    void *buf, int *buf_len)
584 {
585 	void *end = buf + *buf_len;
586 	void *p;
587 	int ret;
588 
589 	ret = ceph_auth_add_authorizer_challenge(ac, auth->authorizer,
590 						 reply, reply_len);
591 	if (ret)
592 		return ret;
593 
594 	p = buf;
595 	ceph_encode_32_safe(&p, end, auth->authorizer_buf_len, e_range);
596 	*buf_len = p - buf;
597 	return 0;
598 
599 e_range:
600 	return -ERANGE;
601 }
602 EXPORT_SYMBOL(ceph_auth_handle_svc_reply_more);
603 
604 int ceph_auth_handle_svc_reply_done(struct ceph_auth_client *ac,
605 				    struct ceph_auth_handshake *auth,
606 				    void *reply, int reply_len,
607 				    u8 *session_key, int *session_key_len,
608 				    u8 *con_secret, int *con_secret_len)
609 {
610 	return ceph_auth_verify_authorizer_reply(ac, auth->authorizer,
611 		reply, reply_len, session_key, session_key_len,
612 		con_secret, con_secret_len);
613 }
614 EXPORT_SYMBOL(ceph_auth_handle_svc_reply_done);
615 
616 bool ceph_auth_handle_bad_authorizer(struct ceph_auth_client *ac,
617 				     int peer_type, int used_proto, int result,
618 				     const int *allowed_protos, int proto_cnt,
619 				     const int *allowed_modes, int mode_cnt)
620 {
621 	mutex_lock(&ac->mutex);
622 	WARN_ON(used_proto != ac->protocol);
623 
624 	if (result == -EOPNOTSUPP) {
625 		if (!contains(allowed_protos, proto_cnt, ac->protocol)) {
626 			pr_err("auth protocol '%s' not allowed by %s\n",
627 			       ceph_auth_proto_name(ac->protocol),
628 			       ceph_entity_type_name(peer_type));
629 			goto not_allowed;
630 		}
631 		if (!contains(allowed_modes, mode_cnt, ac->preferred_mode) &&
632 		    (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN ||
633 		     !contains(allowed_modes, mode_cnt, ac->fallback_mode))) {
634 			pr_err("preferred mode '%s' not allowed by %s\n",
635 			       ceph_con_mode_name(ac->preferred_mode),
636 			       ceph_entity_type_name(peer_type));
637 			if (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN)
638 				pr_err("no fallback mode\n");
639 			else
640 				pr_err("fallback mode '%s' not allowed by %s\n",
641 				       ceph_con_mode_name(ac->fallback_mode),
642 				       ceph_entity_type_name(peer_type));
643 			goto not_allowed;
644 		}
645 	}
646 
647 	WARN_ON(result == -EOPNOTSUPP || result >= 0);
648 	pr_err("auth protocol '%s' authorization to %s failed: %d\n",
649 	       ceph_auth_proto_name(ac->protocol),
650 	       ceph_entity_type_name(peer_type), result);
651 
652 	if (ac->ops->invalidate_authorizer)
653 		ac->ops->invalidate_authorizer(ac, peer_type);
654 
655 	mutex_unlock(&ac->mutex);
656 	return true;
657 
658 not_allowed:
659 	mutex_unlock(&ac->mutex);
660 	return false;
661 }
662 EXPORT_SYMBOL(ceph_auth_handle_bad_authorizer);
663