xref: /linux/net/ceph/auth.c (revision c715f13bb30f9f4d1bd8888667ef32e43b6fedc1)
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_obj(*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 	u32 payload_len;
209 	char *result_msg;
210 	u32 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 	ceph_decode_need(&p, end, payload_len, bad);
221 	payload = p;
222 	p += payload_len;
223 	ceph_decode_need(&p, end, sizeof(u32), bad);
224 	result_msg_len = ceph_decode_32(&p);
225 	ceph_decode_need(&p, end, result_msg_len, bad);
226 	result_msg = p;
227 	p += result_msg_len;
228 	if (p != end)
229 		goto bad;
230 
231 	dout(" result %d '%.*s' gid %llu len %d\n", result, result_msg_len,
232 	     result_msg, global_id, payload_len);
233 
234 	payload_end = payload + payload_len;
235 
236 	if (ac->negotiating) {
237 		/* server does not support our protocols? */
238 		if (!protocol && result < 0) {
239 			ret = result;
240 			goto out;
241 		}
242 		/* set up (new) protocol handler? */
243 		if (ac->protocol && ac->protocol != protocol) {
244 			ac->ops->destroy(ac);
245 			ac->protocol = 0;
246 			ac->ops = NULL;
247 		}
248 		if (ac->protocol != protocol) {
249 			ret = init_protocol(ac, protocol);
250 			if (ret) {
251 				pr_err("auth protocol '%s' init failed: %d\n",
252 				       ceph_auth_proto_name(protocol), ret);
253 				goto out;
254 			}
255 		}
256 
257 		ac->negotiating = false;
258 	}
259 
260 	if (result) {
261 		pr_err("auth protocol '%s' mauth authentication failed: %d\n",
262 		       ceph_auth_proto_name(ac->protocol), result);
263 		ret = result;
264 		goto out;
265 	}
266 
267 	ret = ac->ops->handle_reply(ac, global_id, payload, payload_end,
268 				    NULL, NULL, NULL, NULL);
269 	if (ret == -EAGAIN) {
270 		ret = build_request(ac, true, reply_buf, reply_len);
271 		goto out;
272 	} else if (ret) {
273 		goto out;
274 	}
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, global_id, reply, reply + reply_len,
502 				    session_key, session_key_len,
503 				    con_secret, con_secret_len);
504 	WARN_ON(ret == -EAGAIN || ret > 0);
505 	mutex_unlock(&ac->mutex);
506 	return ret;
507 }
508 
509 bool ceph_auth_handle_bad_method(struct ceph_auth_client *ac,
510 				 int used_proto, int result,
511 				 const int *allowed_protos, int proto_cnt,
512 				 const int *allowed_modes, int mode_cnt)
513 {
514 	mutex_lock(&ac->mutex);
515 	WARN_ON(used_proto != ac->protocol);
516 
517 	if (result == -EOPNOTSUPP) {
518 		if (!contains(allowed_protos, proto_cnt, ac->protocol)) {
519 			pr_err("auth protocol '%s' not allowed\n",
520 			       ceph_auth_proto_name(ac->protocol));
521 			goto not_allowed;
522 		}
523 		if (!contains(allowed_modes, mode_cnt, ac->preferred_mode) &&
524 		    (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN ||
525 		     !contains(allowed_modes, mode_cnt, ac->fallback_mode))) {
526 			pr_err("preferred mode '%s' not allowed\n",
527 			       ceph_con_mode_name(ac->preferred_mode));
528 			if (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN)
529 				pr_err("no fallback mode\n");
530 			else
531 				pr_err("fallback mode '%s' not allowed\n",
532 				       ceph_con_mode_name(ac->fallback_mode));
533 			goto not_allowed;
534 		}
535 	}
536 
537 	WARN_ON(result == -EOPNOTSUPP || result >= 0);
538 	pr_err("auth protocol '%s' msgr authentication failed: %d\n",
539 	       ceph_auth_proto_name(ac->protocol), result);
540 
541 	mutex_unlock(&ac->mutex);
542 	return true;
543 
544 not_allowed:
545 	mutex_unlock(&ac->mutex);
546 	return false;
547 }
548 
549 int ceph_auth_get_authorizer(struct ceph_auth_client *ac,
550 			     struct ceph_auth_handshake *auth,
551 			     int peer_type, void *buf, int *buf_len)
552 {
553 	void *end = buf + *buf_len;
554 	int pref_mode, fallb_mode;
555 	int proto;
556 	void *p;
557 	int ret;
558 
559 	ret = __ceph_auth_get_authorizer(ac, auth, peer_type, true, &proto,
560 					 &pref_mode, &fallb_mode);
561 	if (ret)
562 		return ret;
563 
564 	p = buf;
565 	ceph_encode_32_safe(&p, end, proto, e_range);
566 	ret = encode_con_modes(&p, end, pref_mode, fallb_mode);
567 	if (ret)
568 		return ret;
569 
570 	ceph_encode_32_safe(&p, end, auth->authorizer_buf_len, e_range);
571 	*buf_len = p - buf;
572 	return 0;
573 
574 e_range:
575 	return -ERANGE;
576 }
577 EXPORT_SYMBOL(ceph_auth_get_authorizer);
578 
579 int ceph_auth_handle_svc_reply_more(struct ceph_auth_client *ac,
580 				    struct ceph_auth_handshake *auth,
581 				    void *reply, int reply_len,
582 				    void *buf, int *buf_len)
583 {
584 	void *end = buf + *buf_len;
585 	void *p;
586 	int ret;
587 
588 	ret = ceph_auth_add_authorizer_challenge(ac, auth->authorizer,
589 						 reply, reply_len);
590 	if (ret)
591 		return ret;
592 
593 	p = buf;
594 	ceph_encode_32_safe(&p, end, auth->authorizer_buf_len, e_range);
595 	*buf_len = p - buf;
596 	return 0;
597 
598 e_range:
599 	return -ERANGE;
600 }
601 EXPORT_SYMBOL(ceph_auth_handle_svc_reply_more);
602 
603 int ceph_auth_handle_svc_reply_done(struct ceph_auth_client *ac,
604 				    struct ceph_auth_handshake *auth,
605 				    void *reply, int reply_len,
606 				    u8 *session_key, int *session_key_len,
607 				    u8 *con_secret, int *con_secret_len)
608 {
609 	return ceph_auth_verify_authorizer_reply(ac, auth->authorizer,
610 		reply, reply_len, session_key, session_key_len,
611 		con_secret, con_secret_len);
612 }
613 EXPORT_SYMBOL(ceph_auth_handle_svc_reply_done);
614 
615 bool ceph_auth_handle_bad_authorizer(struct ceph_auth_client *ac,
616 				     int peer_type, int used_proto, int result,
617 				     const int *allowed_protos, int proto_cnt,
618 				     const int *allowed_modes, int mode_cnt)
619 {
620 	mutex_lock(&ac->mutex);
621 	WARN_ON(used_proto != ac->protocol);
622 
623 	if (result == -EOPNOTSUPP) {
624 		if (!contains(allowed_protos, proto_cnt, ac->protocol)) {
625 			pr_err("auth protocol '%s' not allowed by %s\n",
626 			       ceph_auth_proto_name(ac->protocol),
627 			       ceph_entity_type_name(peer_type));
628 			goto not_allowed;
629 		}
630 		if (!contains(allowed_modes, mode_cnt, ac->preferred_mode) &&
631 		    (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN ||
632 		     !contains(allowed_modes, mode_cnt, ac->fallback_mode))) {
633 			pr_err("preferred mode '%s' not allowed by %s\n",
634 			       ceph_con_mode_name(ac->preferred_mode),
635 			       ceph_entity_type_name(peer_type));
636 			if (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN)
637 				pr_err("no fallback mode\n");
638 			else
639 				pr_err("fallback mode '%s' not allowed by %s\n",
640 				       ceph_con_mode_name(ac->fallback_mode),
641 				       ceph_entity_type_name(peer_type));
642 			goto not_allowed;
643 		}
644 	}
645 
646 	WARN_ON(result == -EOPNOTSUPP || result >= 0);
647 	pr_err("auth protocol '%s' authorization to %s failed: %d\n",
648 	       ceph_auth_proto_name(ac->protocol),
649 	       ceph_entity_type_name(peer_type), result);
650 
651 	if (ac->ops->invalidate_authorizer)
652 		ac->ops->invalidate_authorizer(ac, peer_type);
653 
654 	mutex_unlock(&ac->mutex);
655 	return true;
656 
657 not_allowed:
658 	mutex_unlock(&ac->mutex);
659 	return false;
660 }
661 EXPORT_SYMBOL(ceph_auth_handle_bad_authorizer);
662