xref: /linux/net/ceph/auth.c (revision fd7d598270724cc787982ea48bbe17ad383a8b7f)
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 void ceph_auth_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 
62 	ac = kzalloc(sizeof(*ac), GFP_NOFS);
63 	if (!ac)
64 		return ERR_PTR(-ENOMEM);
65 
66 	mutex_init(&ac->mutex);
67 	ac->negotiating = true;
68 	if (name)
69 		ac->name = name;
70 	else
71 		ac->name = CEPH_AUTH_NAME_DEFAULT;
72 	ac->key = key;
73 	ac->preferred_mode = con_modes[0];
74 	ac->fallback_mode = con_modes[1];
75 
76 	dout("%s name '%s' preferred_mode %d fallback_mode %d\n", __func__,
77 	     ac->name, ac->preferred_mode, ac->fallback_mode);
78 	return ac;
79 }
80 
81 void ceph_auth_destroy(struct ceph_auth_client *ac)
82 {
83 	dout("auth_destroy %p\n", ac);
84 	if (ac->ops)
85 		ac->ops->destroy(ac);
86 	kfree(ac);
87 }
88 
89 /*
90  * Reset occurs when reconnecting to the monitor.
91  */
92 void ceph_auth_reset(struct ceph_auth_client *ac)
93 {
94 	mutex_lock(&ac->mutex);
95 	dout("auth_reset %p\n", ac);
96 	if (ac->ops && !ac->negotiating)
97 		ac->ops->reset(ac);
98 	ac->negotiating = true;
99 	mutex_unlock(&ac->mutex);
100 }
101 
102 /*
103  * EntityName, not to be confused with entity_name_t
104  */
105 int ceph_auth_entity_name_encode(const char *name, void **p, void *end)
106 {
107 	int len = strlen(name);
108 
109 	if (*p + 2*sizeof(u32) + len > end)
110 		return -ERANGE;
111 	ceph_encode_32(p, CEPH_ENTITY_TYPE_CLIENT);
112 	ceph_encode_32(p, len);
113 	ceph_encode_copy(p, name, len);
114 	return 0;
115 }
116 
117 /*
118  * Initiate protocol negotiation with monitor.  Include entity name
119  * and list supported protocols.
120  */
121 int ceph_auth_build_hello(struct ceph_auth_client *ac, void *buf, size_t len)
122 {
123 	struct ceph_mon_request_header *monhdr = buf;
124 	void *p = monhdr + 1, *end = buf + len, *lenp;
125 	int i, num;
126 	int ret;
127 
128 	mutex_lock(&ac->mutex);
129 	dout("auth_build_hello\n");
130 	monhdr->have_version = 0;
131 	monhdr->session_mon = cpu_to_le16(-1);
132 	monhdr->session_mon_tid = 0;
133 
134 	ceph_encode_32(&p, CEPH_AUTH_UNKNOWN);  /* no protocol, yet */
135 
136 	lenp = p;
137 	p += sizeof(u32);
138 
139 	ceph_decode_need(&p, end, 1 + sizeof(u32), bad);
140 	ceph_encode_8(&p, 1);
141 	num = ARRAY_SIZE(supported_protocols);
142 	ceph_encode_32(&p, num);
143 	ceph_decode_need(&p, end, num * sizeof(u32), bad);
144 	for (i = 0; i < num; i++)
145 		ceph_encode_32(&p, supported_protocols[i]);
146 
147 	ret = ceph_auth_entity_name_encode(ac->name, &p, end);
148 	if (ret < 0)
149 		goto out;
150 	ceph_decode_need(&p, end, sizeof(u64), bad);
151 	ceph_encode_64(&p, ac->global_id);
152 
153 	ceph_encode_32(&lenp, p - lenp - sizeof(u32));
154 	ret = p - buf;
155 out:
156 	mutex_unlock(&ac->mutex);
157 	return ret;
158 
159 bad:
160 	ret = -ERANGE;
161 	goto out;
162 }
163 
164 static int build_request(struct ceph_auth_client *ac, bool add_header,
165 			 void *buf, int buf_len)
166 {
167 	void *end = buf + buf_len;
168 	void *p;
169 	int ret;
170 
171 	p = buf;
172 	if (add_header) {
173 		/* struct ceph_mon_request_header + protocol */
174 		ceph_encode_64_safe(&p, end, 0, e_range);
175 		ceph_encode_16_safe(&p, end, -1, e_range);
176 		ceph_encode_64_safe(&p, end, 0, e_range);
177 		ceph_encode_32_safe(&p, end, ac->protocol, e_range);
178 	}
179 
180 	ceph_encode_need(&p, end, sizeof(u32), e_range);
181 	ret = ac->ops->build_request(ac, p + sizeof(u32), end);
182 	if (ret < 0) {
183 		pr_err("auth protocol '%s' building request failed: %d\n",
184 		       ceph_auth_proto_name(ac->protocol), ret);
185 		return ret;
186 	}
187 	dout(" built request %d bytes\n", ret);
188 	ceph_encode_32(&p, ret);
189 	return p + ret - buf;
190 
191 e_range:
192 	return -ERANGE;
193 }
194 
195 /*
196  * Handle auth message from monitor.
197  */
198 int ceph_handle_auth_reply(struct ceph_auth_client *ac,
199 			   void *buf, size_t len,
200 			   void *reply_buf, size_t reply_len)
201 {
202 	void *p = buf;
203 	void *end = buf + len;
204 	int protocol;
205 	s32 result;
206 	u64 global_id;
207 	void *payload, *payload_end;
208 	int payload_len;
209 	char *result_msg;
210 	int result_msg_len;
211 	int ret = -EINVAL;
212 
213 	mutex_lock(&ac->mutex);
214 	dout("handle_auth_reply %p %p\n", p, end);
215 	ceph_decode_need(&p, end, sizeof(u32) * 3 + sizeof(u64), bad);
216 	protocol = ceph_decode_32(&p);
217 	result = ceph_decode_32(&p);
218 	global_id = ceph_decode_64(&p);
219 	payload_len = ceph_decode_32(&p);
220 	payload = p;
221 	p += payload_len;
222 	ceph_decode_need(&p, end, sizeof(u32), bad);
223 	result_msg_len = ceph_decode_32(&p);
224 	result_msg = p;
225 	p += result_msg_len;
226 	if (p != end)
227 		goto bad;
228 
229 	dout(" result %d '%.*s' gid %llu len %d\n", result, result_msg_len,
230 	     result_msg, global_id, payload_len);
231 
232 	payload_end = payload + payload_len;
233 
234 	if (ac->negotiating) {
235 		/* server does not support our protocols? */
236 		if (!protocol && result < 0) {
237 			ret = result;
238 			goto out;
239 		}
240 		/* set up (new) protocol handler? */
241 		if (ac->protocol && ac->protocol != protocol) {
242 			ac->ops->destroy(ac);
243 			ac->protocol = 0;
244 			ac->ops = NULL;
245 		}
246 		if (ac->protocol != protocol) {
247 			ret = init_protocol(ac, protocol);
248 			if (ret) {
249 				pr_err("auth protocol '%s' init failed: %d\n",
250 				       ceph_auth_proto_name(protocol), ret);
251 				goto out;
252 			}
253 		}
254 
255 		ac->negotiating = false;
256 	}
257 
258 	if (result) {
259 		pr_err("auth protocol '%s' mauth authentication failed: %d\n",
260 		       ceph_auth_proto_name(ac->protocol), result);
261 		ret = result;
262 		goto out;
263 	}
264 
265 	ret = ac->ops->handle_reply(ac, global_id, payload, payload_end,
266 				    NULL, NULL, NULL, NULL);
267 	if (ret == -EAGAIN) {
268 		ret = build_request(ac, true, reply_buf, reply_len);
269 		goto out;
270 	} else if (ret) {
271 		goto out;
272 	}
273 
274 out:
275 	mutex_unlock(&ac->mutex);
276 	return ret;
277 
278 bad:
279 	pr_err("failed to decode auth msg\n");
280 	ret = -EINVAL;
281 	goto out;
282 }
283 
284 int ceph_build_auth(struct ceph_auth_client *ac,
285 		    void *msg_buf, size_t msg_len)
286 {
287 	int ret = 0;
288 
289 	mutex_lock(&ac->mutex);
290 	if (ac->ops->should_authenticate(ac))
291 		ret = build_request(ac, true, msg_buf, msg_len);
292 	mutex_unlock(&ac->mutex);
293 	return ret;
294 }
295 
296 int ceph_auth_is_authenticated(struct ceph_auth_client *ac)
297 {
298 	int ret = 0;
299 
300 	mutex_lock(&ac->mutex);
301 	if (ac->ops)
302 		ret = ac->ops->is_authenticated(ac);
303 	mutex_unlock(&ac->mutex);
304 	return ret;
305 }
306 EXPORT_SYMBOL(ceph_auth_is_authenticated);
307 
308 int __ceph_auth_get_authorizer(struct ceph_auth_client *ac,
309 			       struct ceph_auth_handshake *auth,
310 			       int peer_type, bool force_new,
311 			       int *proto, int *pref_mode, int *fallb_mode)
312 {
313 	int ret;
314 
315 	mutex_lock(&ac->mutex);
316 	if (force_new && auth->authorizer) {
317 		ceph_auth_destroy_authorizer(auth->authorizer);
318 		auth->authorizer = NULL;
319 	}
320 	if (!auth->authorizer)
321 		ret = ac->ops->create_authorizer(ac, peer_type, auth);
322 	else if (ac->ops->update_authorizer)
323 		ret = ac->ops->update_authorizer(ac, peer_type, auth);
324 	else
325 		ret = 0;
326 	if (ret)
327 		goto out;
328 
329 	*proto = ac->protocol;
330 	if (pref_mode && fallb_mode) {
331 		*pref_mode = ac->preferred_mode;
332 		*fallb_mode = ac->fallback_mode;
333 	}
334 
335 out:
336 	mutex_unlock(&ac->mutex);
337 	return ret;
338 }
339 EXPORT_SYMBOL(__ceph_auth_get_authorizer);
340 
341 void ceph_auth_destroy_authorizer(struct ceph_authorizer *a)
342 {
343 	a->destroy(a);
344 }
345 EXPORT_SYMBOL(ceph_auth_destroy_authorizer);
346 
347 int ceph_auth_add_authorizer_challenge(struct ceph_auth_client *ac,
348 				       struct ceph_authorizer *a,
349 				       void *challenge_buf,
350 				       int challenge_buf_len)
351 {
352 	int ret = 0;
353 
354 	mutex_lock(&ac->mutex);
355 	if (ac->ops && ac->ops->add_authorizer_challenge)
356 		ret = ac->ops->add_authorizer_challenge(ac, a, challenge_buf,
357 							challenge_buf_len);
358 	mutex_unlock(&ac->mutex);
359 	return ret;
360 }
361 EXPORT_SYMBOL(ceph_auth_add_authorizer_challenge);
362 
363 int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac,
364 				      struct ceph_authorizer *a,
365 				      void *reply, int reply_len,
366 				      u8 *session_key, int *session_key_len,
367 				      u8 *con_secret, int *con_secret_len)
368 {
369 	int ret = 0;
370 
371 	mutex_lock(&ac->mutex);
372 	if (ac->ops && ac->ops->verify_authorizer_reply)
373 		ret = ac->ops->verify_authorizer_reply(ac, a,
374 			reply, reply_len, session_key, session_key_len,
375 			con_secret, con_secret_len);
376 	mutex_unlock(&ac->mutex);
377 	return ret;
378 }
379 EXPORT_SYMBOL(ceph_auth_verify_authorizer_reply);
380 
381 void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac, int peer_type)
382 {
383 	mutex_lock(&ac->mutex);
384 	if (ac->ops && ac->ops->invalidate_authorizer)
385 		ac->ops->invalidate_authorizer(ac, peer_type);
386 	mutex_unlock(&ac->mutex);
387 }
388 EXPORT_SYMBOL(ceph_auth_invalidate_authorizer);
389 
390 /*
391  * msgr2 authentication
392  */
393 
394 static bool contains(const int *arr, int cnt, int val)
395 {
396 	int i;
397 
398 	for (i = 0; i < cnt; i++) {
399 		if (arr[i] == val)
400 			return true;
401 	}
402 
403 	return false;
404 }
405 
406 static int encode_con_modes(void **p, void *end, int pref_mode, int fallb_mode)
407 {
408 	WARN_ON(pref_mode == CEPH_CON_MODE_UNKNOWN);
409 	if (fallb_mode != CEPH_CON_MODE_UNKNOWN) {
410 		ceph_encode_32_safe(p, end, 2, e_range);
411 		ceph_encode_32_safe(p, end, pref_mode, e_range);
412 		ceph_encode_32_safe(p, end, fallb_mode, e_range);
413 	} else {
414 		ceph_encode_32_safe(p, end, 1, e_range);
415 		ceph_encode_32_safe(p, end, pref_mode, e_range);
416 	}
417 
418 	return 0;
419 
420 e_range:
421 	return -ERANGE;
422 }
423 
424 /*
425  * Similar to ceph_auth_build_hello().
426  */
427 int ceph_auth_get_request(struct ceph_auth_client *ac, void *buf, int buf_len)
428 {
429 	int proto = ac->key ? CEPH_AUTH_CEPHX : CEPH_AUTH_NONE;
430 	void *end = buf + buf_len;
431 	void *lenp;
432 	void *p;
433 	int ret;
434 
435 	mutex_lock(&ac->mutex);
436 	if (ac->protocol == CEPH_AUTH_UNKNOWN) {
437 		ret = init_protocol(ac, proto);
438 		if (ret) {
439 			pr_err("auth protocol '%s' init failed: %d\n",
440 			       ceph_auth_proto_name(proto), ret);
441 			goto out;
442 		}
443 	} else {
444 		WARN_ON(ac->protocol != proto);
445 		ac->ops->reset(ac);
446 	}
447 
448 	p = buf;
449 	ceph_encode_32_safe(&p, end, ac->protocol, e_range);
450 	ret = encode_con_modes(&p, end, ac->preferred_mode, ac->fallback_mode);
451 	if (ret)
452 		goto out;
453 
454 	lenp = p;
455 	p += 4;  /* space for len */
456 
457 	ceph_encode_8_safe(&p, end, CEPH_AUTH_MODE_MON, e_range);
458 	ret = ceph_auth_entity_name_encode(ac->name, &p, end);
459 	if (ret)
460 		goto out;
461 
462 	ceph_encode_64_safe(&p, end, ac->global_id, e_range);
463 	ceph_encode_32(&lenp, p - lenp - 4);
464 	ret = p - buf;
465 
466 out:
467 	mutex_unlock(&ac->mutex);
468 	return ret;
469 
470 e_range:
471 	ret = -ERANGE;
472 	goto out;
473 }
474 
475 int ceph_auth_handle_reply_more(struct ceph_auth_client *ac, void *reply,
476 				int reply_len, void *buf, int buf_len)
477 {
478 	int ret;
479 
480 	mutex_lock(&ac->mutex);
481 	ret = ac->ops->handle_reply(ac, 0, reply, reply + reply_len,
482 				    NULL, NULL, NULL, NULL);
483 	if (ret == -EAGAIN)
484 		ret = build_request(ac, false, buf, buf_len);
485 	else
486 		WARN_ON(ret >= 0);
487 	mutex_unlock(&ac->mutex);
488 	return ret;
489 }
490 
491 int ceph_auth_handle_reply_done(struct ceph_auth_client *ac,
492 				u64 global_id, void *reply, int reply_len,
493 				u8 *session_key, int *session_key_len,
494 				u8 *con_secret, int *con_secret_len)
495 {
496 	int ret;
497 
498 	mutex_lock(&ac->mutex);
499 	ret = ac->ops->handle_reply(ac, global_id, reply, reply + reply_len,
500 				    session_key, session_key_len,
501 				    con_secret, con_secret_len);
502 	WARN_ON(ret == -EAGAIN || ret > 0);
503 	mutex_unlock(&ac->mutex);
504 	return ret;
505 }
506 
507 bool ceph_auth_handle_bad_method(struct ceph_auth_client *ac,
508 				 int used_proto, int result,
509 				 const int *allowed_protos, int proto_cnt,
510 				 const int *allowed_modes, int mode_cnt)
511 {
512 	mutex_lock(&ac->mutex);
513 	WARN_ON(used_proto != ac->protocol);
514 
515 	if (result == -EOPNOTSUPP) {
516 		if (!contains(allowed_protos, proto_cnt, ac->protocol)) {
517 			pr_err("auth protocol '%s' not allowed\n",
518 			       ceph_auth_proto_name(ac->protocol));
519 			goto not_allowed;
520 		}
521 		if (!contains(allowed_modes, mode_cnt, ac->preferred_mode) &&
522 		    (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN ||
523 		     !contains(allowed_modes, mode_cnt, ac->fallback_mode))) {
524 			pr_err("preferred mode '%s' not allowed\n",
525 			       ceph_con_mode_name(ac->preferred_mode));
526 			if (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN)
527 				pr_err("no fallback mode\n");
528 			else
529 				pr_err("fallback mode '%s' not allowed\n",
530 				       ceph_con_mode_name(ac->fallback_mode));
531 			goto not_allowed;
532 		}
533 	}
534 
535 	WARN_ON(result == -EOPNOTSUPP || result >= 0);
536 	pr_err("auth protocol '%s' msgr authentication failed: %d\n",
537 	       ceph_auth_proto_name(ac->protocol), result);
538 
539 	mutex_unlock(&ac->mutex);
540 	return true;
541 
542 not_allowed:
543 	mutex_unlock(&ac->mutex);
544 	return false;
545 }
546 
547 int ceph_auth_get_authorizer(struct ceph_auth_client *ac,
548 			     struct ceph_auth_handshake *auth,
549 			     int peer_type, void *buf, int *buf_len)
550 {
551 	void *end = buf + *buf_len;
552 	int pref_mode, fallb_mode;
553 	int proto;
554 	void *p;
555 	int ret;
556 
557 	ret = __ceph_auth_get_authorizer(ac, auth, peer_type, true, &proto,
558 					 &pref_mode, &fallb_mode);
559 	if (ret)
560 		return ret;
561 
562 	p = buf;
563 	ceph_encode_32_safe(&p, end, proto, e_range);
564 	ret = encode_con_modes(&p, end, pref_mode, fallb_mode);
565 	if (ret)
566 		return ret;
567 
568 	ceph_encode_32_safe(&p, end, auth->authorizer_buf_len, e_range);
569 	*buf_len = p - buf;
570 	return 0;
571 
572 e_range:
573 	return -ERANGE;
574 }
575 EXPORT_SYMBOL(ceph_auth_get_authorizer);
576 
577 int ceph_auth_handle_svc_reply_more(struct ceph_auth_client *ac,
578 				    struct ceph_auth_handshake *auth,
579 				    void *reply, int reply_len,
580 				    void *buf, int *buf_len)
581 {
582 	void *end = buf + *buf_len;
583 	void *p;
584 	int ret;
585 
586 	ret = ceph_auth_add_authorizer_challenge(ac, auth->authorizer,
587 						 reply, reply_len);
588 	if (ret)
589 		return ret;
590 
591 	p = buf;
592 	ceph_encode_32_safe(&p, end, auth->authorizer_buf_len, e_range);
593 	*buf_len = p - buf;
594 	return 0;
595 
596 e_range:
597 	return -ERANGE;
598 }
599 EXPORT_SYMBOL(ceph_auth_handle_svc_reply_more);
600 
601 int ceph_auth_handle_svc_reply_done(struct ceph_auth_client *ac,
602 				    struct ceph_auth_handshake *auth,
603 				    void *reply, int reply_len,
604 				    u8 *session_key, int *session_key_len,
605 				    u8 *con_secret, int *con_secret_len)
606 {
607 	return ceph_auth_verify_authorizer_reply(ac, auth->authorizer,
608 		reply, reply_len, session_key, session_key_len,
609 		con_secret, con_secret_len);
610 }
611 EXPORT_SYMBOL(ceph_auth_handle_svc_reply_done);
612 
613 bool ceph_auth_handle_bad_authorizer(struct ceph_auth_client *ac,
614 				     int peer_type, int used_proto, int result,
615 				     const int *allowed_protos, int proto_cnt,
616 				     const int *allowed_modes, int mode_cnt)
617 {
618 	mutex_lock(&ac->mutex);
619 	WARN_ON(used_proto != ac->protocol);
620 
621 	if (result == -EOPNOTSUPP) {
622 		if (!contains(allowed_protos, proto_cnt, ac->protocol)) {
623 			pr_err("auth protocol '%s' not allowed by %s\n",
624 			       ceph_auth_proto_name(ac->protocol),
625 			       ceph_entity_type_name(peer_type));
626 			goto not_allowed;
627 		}
628 		if (!contains(allowed_modes, mode_cnt, ac->preferred_mode) &&
629 		    (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN ||
630 		     !contains(allowed_modes, mode_cnt, ac->fallback_mode))) {
631 			pr_err("preferred mode '%s' not allowed by %s\n",
632 			       ceph_con_mode_name(ac->preferred_mode),
633 			       ceph_entity_type_name(peer_type));
634 			if (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN)
635 				pr_err("no fallback mode\n");
636 			else
637 				pr_err("fallback mode '%s' not allowed by %s\n",
638 				       ceph_con_mode_name(ac->fallback_mode),
639 				       ceph_entity_type_name(peer_type));
640 			goto not_allowed;
641 		}
642 	}
643 
644 	WARN_ON(result == -EOPNOTSUPP || result >= 0);
645 	pr_err("auth protocol '%s' authorization to %s failed: %d\n",
646 	       ceph_auth_proto_name(ac->protocol),
647 	       ceph_entity_type_name(peer_type), result);
648 
649 	if (ac->ops->invalidate_authorizer)
650 		ac->ops->invalidate_authorizer(ac, peer_type);
651 
652 	mutex_unlock(&ac->mutex);
653 	return true;
654 
655 not_allowed:
656 	mutex_unlock(&ac->mutex);
657 	return false;
658 }
659 EXPORT_SYMBOL(ceph_auth_handle_bad_authorizer);
660