xref: /openbmc/linux/net/ceph/auth.c (revision d9fd5a71)
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 /*
40  * setup, teardown.
41  */
42 struct ceph_auth_client *ceph_auth_init(const char *name,
43 					const struct ceph_crypto_key *key,
44 					const int *con_modes)
45 {
46 	struct ceph_auth_client *ac;
47 	int ret;
48 
49 	ret = -ENOMEM;
50 	ac = kzalloc(sizeof(*ac), GFP_NOFS);
51 	if (!ac)
52 		goto out;
53 
54 	mutex_init(&ac->mutex);
55 	ac->negotiating = true;
56 	if (name)
57 		ac->name = name;
58 	else
59 		ac->name = CEPH_AUTH_NAME_DEFAULT;
60 	ac->key = key;
61 	ac->preferred_mode = con_modes[0];
62 	ac->fallback_mode = con_modes[1];
63 
64 	dout("%s name '%s' preferred_mode %d fallback_mode %d\n", __func__,
65 	     ac->name, ac->preferred_mode, ac->fallback_mode);
66 	return ac;
67 
68 out:
69 	return ERR_PTR(ret);
70 }
71 
72 void ceph_auth_destroy(struct ceph_auth_client *ac)
73 {
74 	dout("auth_destroy %p\n", ac);
75 	if (ac->ops)
76 		ac->ops->destroy(ac);
77 	kfree(ac);
78 }
79 
80 /*
81  * Reset occurs when reconnecting to the monitor.
82  */
83 void ceph_auth_reset(struct ceph_auth_client *ac)
84 {
85 	mutex_lock(&ac->mutex);
86 	dout("auth_reset %p\n", ac);
87 	if (ac->ops && !ac->negotiating)
88 		ac->ops->reset(ac);
89 	ac->negotiating = true;
90 	mutex_unlock(&ac->mutex);
91 }
92 
93 /*
94  * EntityName, not to be confused with entity_name_t
95  */
96 int ceph_auth_entity_name_encode(const char *name, void **p, void *end)
97 {
98 	int len = strlen(name);
99 
100 	if (*p + 2*sizeof(u32) + len > end)
101 		return -ERANGE;
102 	ceph_encode_32(p, CEPH_ENTITY_TYPE_CLIENT);
103 	ceph_encode_32(p, len);
104 	ceph_encode_copy(p, name, len);
105 	return 0;
106 }
107 
108 /*
109  * Initiate protocol negotiation with monitor.  Include entity name
110  * and list supported protocols.
111  */
112 int ceph_auth_build_hello(struct ceph_auth_client *ac, void *buf, size_t len)
113 {
114 	struct ceph_mon_request_header *monhdr = buf;
115 	void *p = monhdr + 1, *end = buf + len, *lenp;
116 	int i, num;
117 	int ret;
118 
119 	mutex_lock(&ac->mutex);
120 	dout("auth_build_hello\n");
121 	monhdr->have_version = 0;
122 	monhdr->session_mon = cpu_to_le16(-1);
123 	monhdr->session_mon_tid = 0;
124 
125 	ceph_encode_32(&p, CEPH_AUTH_UNKNOWN);  /* no protocol, yet */
126 
127 	lenp = p;
128 	p += sizeof(u32);
129 
130 	ceph_decode_need(&p, end, 1 + sizeof(u32), bad);
131 	ceph_encode_8(&p, 1);
132 	num = ARRAY_SIZE(supported_protocols);
133 	ceph_encode_32(&p, num);
134 	ceph_decode_need(&p, end, num * sizeof(u32), bad);
135 	for (i = 0; i < num; i++)
136 		ceph_encode_32(&p, supported_protocols[i]);
137 
138 	ret = ceph_auth_entity_name_encode(ac->name, &p, end);
139 	if (ret < 0)
140 		goto out;
141 	ceph_decode_need(&p, end, sizeof(u64), bad);
142 	ceph_encode_64(&p, ac->global_id);
143 
144 	ceph_encode_32(&lenp, p - lenp - sizeof(u32));
145 	ret = p - buf;
146 out:
147 	mutex_unlock(&ac->mutex);
148 	return ret;
149 
150 bad:
151 	ret = -ERANGE;
152 	goto out;
153 }
154 
155 static int build_request(struct ceph_auth_client *ac, bool add_header,
156 			 void *buf, int buf_len)
157 {
158 	void *end = buf + buf_len;
159 	void *p;
160 	int ret;
161 
162 	p = buf;
163 	if (add_header) {
164 		/* struct ceph_mon_request_header + protocol */
165 		ceph_encode_64_safe(&p, end, 0, e_range);
166 		ceph_encode_16_safe(&p, end, -1, e_range);
167 		ceph_encode_64_safe(&p, end, 0, e_range);
168 		ceph_encode_32_safe(&p, end, ac->protocol, e_range);
169 	}
170 
171 	ceph_encode_need(&p, end, sizeof(u32), e_range);
172 	ret = ac->ops->build_request(ac, p + sizeof(u32), end);
173 	if (ret < 0) {
174 		pr_err("auth protocol '%s' building request failed: %d\n",
175 		       ceph_auth_proto_name(ac->protocol), ret);
176 		return ret;
177 	}
178 	dout(" built request %d bytes\n", ret);
179 	ceph_encode_32(&p, ret);
180 	return p + ret - buf;
181 
182 e_range:
183 	return -ERANGE;
184 }
185 
186 /*
187  * Handle auth message from monitor.
188  */
189 int ceph_handle_auth_reply(struct ceph_auth_client *ac,
190 			   void *buf, size_t len,
191 			   void *reply_buf, size_t reply_len)
192 {
193 	void *p = buf;
194 	void *end = buf + len;
195 	int protocol;
196 	s32 result;
197 	u64 global_id;
198 	void *payload, *payload_end;
199 	int payload_len;
200 	char *result_msg;
201 	int result_msg_len;
202 	int ret = -EINVAL;
203 
204 	mutex_lock(&ac->mutex);
205 	dout("handle_auth_reply %p %p\n", p, end);
206 	ceph_decode_need(&p, end, sizeof(u32) * 3 + sizeof(u64), bad);
207 	protocol = ceph_decode_32(&p);
208 	result = ceph_decode_32(&p);
209 	global_id = ceph_decode_64(&p);
210 	payload_len = ceph_decode_32(&p);
211 	payload = p;
212 	p += payload_len;
213 	ceph_decode_need(&p, end, sizeof(u32), bad);
214 	result_msg_len = ceph_decode_32(&p);
215 	result_msg = p;
216 	p += result_msg_len;
217 	if (p != end)
218 		goto bad;
219 
220 	dout(" result %d '%.*s' gid %llu len %d\n", result, result_msg_len,
221 	     result_msg, global_id, payload_len);
222 
223 	payload_end = payload + payload_len;
224 
225 	if (global_id && ac->global_id != global_id) {
226 		dout(" set global_id %lld -> %lld\n", ac->global_id, global_id);
227 		ac->global_id = global_id;
228 	}
229 
230 	if (ac->negotiating) {
231 		/* server does not support our protocols? */
232 		if (!protocol && result < 0) {
233 			ret = result;
234 			goto out;
235 		}
236 		/* set up (new) protocol handler? */
237 		if (ac->protocol && ac->protocol != protocol) {
238 			ac->ops->destroy(ac);
239 			ac->protocol = 0;
240 			ac->ops = NULL;
241 		}
242 		if (ac->protocol != protocol) {
243 			ret = init_protocol(ac, protocol);
244 			if (ret) {
245 				pr_err("auth protocol '%s' init failed: %d\n",
246 				       ceph_auth_proto_name(protocol), ret);
247 				goto out;
248 			}
249 		}
250 
251 		ac->negotiating = false;
252 	}
253 
254 	ret = ac->ops->handle_reply(ac, result, payload, payload_end,
255 				    NULL, NULL, NULL, NULL);
256 	if (ret == -EAGAIN)
257 		ret = build_request(ac, true, reply_buf, reply_len);
258 	else if (ret)
259 		pr_err("auth protocol '%s' mauth authentication failed: %d\n",
260 		       ceph_auth_proto_name(ac->protocol), result);
261 
262 out:
263 	mutex_unlock(&ac->mutex);
264 	return ret;
265 
266 bad:
267 	pr_err("failed to decode auth msg\n");
268 	ret = -EINVAL;
269 	goto out;
270 }
271 
272 int ceph_build_auth(struct ceph_auth_client *ac,
273 		    void *msg_buf, size_t msg_len)
274 {
275 	int ret = 0;
276 
277 	mutex_lock(&ac->mutex);
278 	if (ac->ops->should_authenticate(ac))
279 		ret = build_request(ac, true, msg_buf, msg_len);
280 	mutex_unlock(&ac->mutex);
281 	return ret;
282 }
283 
284 int ceph_auth_is_authenticated(struct ceph_auth_client *ac)
285 {
286 	int ret = 0;
287 
288 	mutex_lock(&ac->mutex);
289 	if (ac->ops)
290 		ret = ac->ops->is_authenticated(ac);
291 	mutex_unlock(&ac->mutex);
292 	return ret;
293 }
294 EXPORT_SYMBOL(ceph_auth_is_authenticated);
295 
296 int __ceph_auth_get_authorizer(struct ceph_auth_client *ac,
297 			       struct ceph_auth_handshake *auth,
298 			       int peer_type, bool force_new,
299 			       int *proto, int *pref_mode, int *fallb_mode)
300 {
301 	int ret;
302 
303 	mutex_lock(&ac->mutex);
304 	if (force_new && auth->authorizer) {
305 		ceph_auth_destroy_authorizer(auth->authorizer);
306 		auth->authorizer = NULL;
307 	}
308 	if (!auth->authorizer)
309 		ret = ac->ops->create_authorizer(ac, peer_type, auth);
310 	else if (ac->ops->update_authorizer)
311 		ret = ac->ops->update_authorizer(ac, peer_type, auth);
312 	else
313 		ret = 0;
314 	if (ret)
315 		goto out;
316 
317 	*proto = ac->protocol;
318 	if (pref_mode && fallb_mode) {
319 		*pref_mode = ac->preferred_mode;
320 		*fallb_mode = ac->fallback_mode;
321 	}
322 
323 out:
324 	mutex_unlock(&ac->mutex);
325 	return ret;
326 }
327 EXPORT_SYMBOL(__ceph_auth_get_authorizer);
328 
329 void ceph_auth_destroy_authorizer(struct ceph_authorizer *a)
330 {
331 	a->destroy(a);
332 }
333 EXPORT_SYMBOL(ceph_auth_destroy_authorizer);
334 
335 int ceph_auth_add_authorizer_challenge(struct ceph_auth_client *ac,
336 				       struct ceph_authorizer *a,
337 				       void *challenge_buf,
338 				       int challenge_buf_len)
339 {
340 	int ret = 0;
341 
342 	mutex_lock(&ac->mutex);
343 	if (ac->ops && ac->ops->add_authorizer_challenge)
344 		ret = ac->ops->add_authorizer_challenge(ac, a, challenge_buf,
345 							challenge_buf_len);
346 	mutex_unlock(&ac->mutex);
347 	return ret;
348 }
349 EXPORT_SYMBOL(ceph_auth_add_authorizer_challenge);
350 
351 int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac,
352 				      struct ceph_authorizer *a,
353 				      void *reply, int reply_len,
354 				      u8 *session_key, int *session_key_len,
355 				      u8 *con_secret, int *con_secret_len)
356 {
357 	int ret = 0;
358 
359 	mutex_lock(&ac->mutex);
360 	if (ac->ops && ac->ops->verify_authorizer_reply)
361 		ret = ac->ops->verify_authorizer_reply(ac, a,
362 			reply, reply_len, session_key, session_key_len,
363 			con_secret, con_secret_len);
364 	mutex_unlock(&ac->mutex);
365 	return ret;
366 }
367 EXPORT_SYMBOL(ceph_auth_verify_authorizer_reply);
368 
369 void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac, int peer_type)
370 {
371 	mutex_lock(&ac->mutex);
372 	if (ac->ops && ac->ops->invalidate_authorizer)
373 		ac->ops->invalidate_authorizer(ac, peer_type);
374 	mutex_unlock(&ac->mutex);
375 }
376 EXPORT_SYMBOL(ceph_auth_invalidate_authorizer);
377 
378 /*
379  * msgr2 authentication
380  */
381 
382 static bool contains(const int *arr, int cnt, int val)
383 {
384 	int i;
385 
386 	for (i = 0; i < cnt; i++) {
387 		if (arr[i] == val)
388 			return true;
389 	}
390 
391 	return false;
392 }
393 
394 static int encode_con_modes(void **p, void *end, int pref_mode, int fallb_mode)
395 {
396 	WARN_ON(pref_mode == CEPH_CON_MODE_UNKNOWN);
397 	if (fallb_mode != CEPH_CON_MODE_UNKNOWN) {
398 		ceph_encode_32_safe(p, end, 2, e_range);
399 		ceph_encode_32_safe(p, end, pref_mode, e_range);
400 		ceph_encode_32_safe(p, end, fallb_mode, e_range);
401 	} else {
402 		ceph_encode_32_safe(p, end, 1, e_range);
403 		ceph_encode_32_safe(p, end, pref_mode, e_range);
404 	}
405 
406 	return 0;
407 
408 e_range:
409 	return -ERANGE;
410 }
411 
412 /*
413  * Similar to ceph_auth_build_hello().
414  */
415 int ceph_auth_get_request(struct ceph_auth_client *ac, void *buf, int buf_len)
416 {
417 	int proto = ac->key ? CEPH_AUTH_CEPHX : CEPH_AUTH_NONE;
418 	void *end = buf + buf_len;
419 	void *lenp;
420 	void *p;
421 	int ret;
422 
423 	mutex_lock(&ac->mutex);
424 	if (ac->protocol == CEPH_AUTH_UNKNOWN) {
425 		ret = init_protocol(ac, proto);
426 		if (ret) {
427 			pr_err("auth protocol '%s' init failed: %d\n",
428 			       ceph_auth_proto_name(proto), ret);
429 			goto out;
430 		}
431 	} else {
432 		WARN_ON(ac->protocol != proto);
433 		ac->ops->reset(ac);
434 	}
435 
436 	p = buf;
437 	ceph_encode_32_safe(&p, end, ac->protocol, e_range);
438 	ret = encode_con_modes(&p, end, ac->preferred_mode, ac->fallback_mode);
439 	if (ret)
440 		goto out;
441 
442 	lenp = p;
443 	p += 4;  /* space for len */
444 
445 	ceph_encode_8_safe(&p, end, CEPH_AUTH_MODE_MON, e_range);
446 	ret = ceph_auth_entity_name_encode(ac->name, &p, end);
447 	if (ret)
448 		goto out;
449 
450 	ceph_encode_64_safe(&p, end, ac->global_id, e_range);
451 	ceph_encode_32(&lenp, p - lenp - 4);
452 	ret = p - buf;
453 
454 out:
455 	mutex_unlock(&ac->mutex);
456 	return ret;
457 
458 e_range:
459 	ret = -ERANGE;
460 	goto out;
461 }
462 
463 int ceph_auth_handle_reply_more(struct ceph_auth_client *ac, void *reply,
464 				int reply_len, void *buf, int buf_len)
465 {
466 	int ret;
467 
468 	mutex_lock(&ac->mutex);
469 	ret = ac->ops->handle_reply(ac, 0, reply, reply + reply_len,
470 				    NULL, NULL, NULL, NULL);
471 	if (ret == -EAGAIN)
472 		ret = build_request(ac, false, buf, buf_len);
473 	else
474 		WARN_ON(ret >= 0);
475 	mutex_unlock(&ac->mutex);
476 	return ret;
477 }
478 
479 int ceph_auth_handle_reply_done(struct ceph_auth_client *ac,
480 				u64 global_id, void *reply, int reply_len,
481 				u8 *session_key, int *session_key_len,
482 				u8 *con_secret, int *con_secret_len)
483 {
484 	int ret;
485 
486 	mutex_lock(&ac->mutex);
487 	if (global_id && ac->global_id != global_id) {
488 		dout("%s global_id %llu -> %llu\n", __func__, ac->global_id,
489 		     global_id);
490 		ac->global_id = global_id;
491 	}
492 
493 	ret = ac->ops->handle_reply(ac, 0, reply, reply + reply_len,
494 				    session_key, session_key_len,
495 				    con_secret, con_secret_len);
496 	mutex_unlock(&ac->mutex);
497 	return ret;
498 }
499 
500 bool ceph_auth_handle_bad_method(struct ceph_auth_client *ac,
501 				 int used_proto, int result,
502 				 const int *allowed_protos, int proto_cnt,
503 				 const int *allowed_modes, int mode_cnt)
504 {
505 	mutex_lock(&ac->mutex);
506 	WARN_ON(used_proto != ac->protocol);
507 
508 	if (result == -EOPNOTSUPP) {
509 		if (!contains(allowed_protos, proto_cnt, ac->protocol)) {
510 			pr_err("auth protocol '%s' not allowed\n",
511 			       ceph_auth_proto_name(ac->protocol));
512 			goto not_allowed;
513 		}
514 		if (!contains(allowed_modes, mode_cnt, ac->preferred_mode) &&
515 		    (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN ||
516 		     !contains(allowed_modes, mode_cnt, ac->fallback_mode))) {
517 			pr_err("preferred mode '%s' not allowed\n",
518 			       ceph_con_mode_name(ac->preferred_mode));
519 			if (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN)
520 				pr_err("no fallback mode\n");
521 			else
522 				pr_err("fallback mode '%s' not allowed\n",
523 				       ceph_con_mode_name(ac->fallback_mode));
524 			goto not_allowed;
525 		}
526 	}
527 
528 	WARN_ON(result == -EOPNOTSUPP || result >= 0);
529 	pr_err("auth protocol '%s' msgr authentication failed: %d\n",
530 	       ceph_auth_proto_name(ac->protocol), result);
531 
532 	mutex_unlock(&ac->mutex);
533 	return true;
534 
535 not_allowed:
536 	mutex_unlock(&ac->mutex);
537 	return false;
538 }
539 
540 int ceph_auth_get_authorizer(struct ceph_auth_client *ac,
541 			     struct ceph_auth_handshake *auth,
542 			     int peer_type, void *buf, int *buf_len)
543 {
544 	void *end = buf + *buf_len;
545 	int pref_mode, fallb_mode;
546 	int proto;
547 	void *p;
548 	int ret;
549 
550 	ret = __ceph_auth_get_authorizer(ac, auth, peer_type, true, &proto,
551 					 &pref_mode, &fallb_mode);
552 	if (ret)
553 		return ret;
554 
555 	p = buf;
556 	ceph_encode_32_safe(&p, end, proto, e_range);
557 	ret = encode_con_modes(&p, end, pref_mode, fallb_mode);
558 	if (ret)
559 		return ret;
560 
561 	ceph_encode_32_safe(&p, end, auth->authorizer_buf_len, e_range);
562 	*buf_len = p - buf;
563 	return 0;
564 
565 e_range:
566 	return -ERANGE;
567 }
568 EXPORT_SYMBOL(ceph_auth_get_authorizer);
569 
570 int ceph_auth_handle_svc_reply_more(struct ceph_auth_client *ac,
571 				    struct ceph_auth_handshake *auth,
572 				    void *reply, int reply_len,
573 				    void *buf, int *buf_len)
574 {
575 	void *end = buf + *buf_len;
576 	void *p;
577 	int ret;
578 
579 	ret = ceph_auth_add_authorizer_challenge(ac, auth->authorizer,
580 						 reply, reply_len);
581 	if (ret)
582 		return ret;
583 
584 	p = buf;
585 	ceph_encode_32_safe(&p, end, auth->authorizer_buf_len, e_range);
586 	*buf_len = p - buf;
587 	return 0;
588 
589 e_range:
590 	return -ERANGE;
591 }
592 EXPORT_SYMBOL(ceph_auth_handle_svc_reply_more);
593 
594 int ceph_auth_handle_svc_reply_done(struct ceph_auth_client *ac,
595 				    struct ceph_auth_handshake *auth,
596 				    void *reply, int reply_len,
597 				    u8 *session_key, int *session_key_len,
598 				    u8 *con_secret, int *con_secret_len)
599 {
600 	return ceph_auth_verify_authorizer_reply(ac, auth->authorizer,
601 		reply, reply_len, session_key, session_key_len,
602 		con_secret, con_secret_len);
603 }
604 EXPORT_SYMBOL(ceph_auth_handle_svc_reply_done);
605 
606 bool ceph_auth_handle_bad_authorizer(struct ceph_auth_client *ac,
607 				     int peer_type, int used_proto, int result,
608 				     const int *allowed_protos, int proto_cnt,
609 				     const int *allowed_modes, int mode_cnt)
610 {
611 	mutex_lock(&ac->mutex);
612 	WARN_ON(used_proto != ac->protocol);
613 
614 	if (result == -EOPNOTSUPP) {
615 		if (!contains(allowed_protos, proto_cnt, ac->protocol)) {
616 			pr_err("auth protocol '%s' not allowed by %s\n",
617 			       ceph_auth_proto_name(ac->protocol),
618 			       ceph_entity_type_name(peer_type));
619 			goto not_allowed;
620 		}
621 		if (!contains(allowed_modes, mode_cnt, ac->preferred_mode) &&
622 		    (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN ||
623 		     !contains(allowed_modes, mode_cnt, ac->fallback_mode))) {
624 			pr_err("preferred mode '%s' not allowed by %s\n",
625 			       ceph_con_mode_name(ac->preferred_mode),
626 			       ceph_entity_type_name(peer_type));
627 			if (ac->fallback_mode == CEPH_CON_MODE_UNKNOWN)
628 				pr_err("no fallback mode\n");
629 			else
630 				pr_err("fallback mode '%s' not allowed by %s\n",
631 				       ceph_con_mode_name(ac->fallback_mode),
632 				       ceph_entity_type_name(peer_type));
633 			goto not_allowed;
634 		}
635 	}
636 
637 	WARN_ON(result == -EOPNOTSUPP || result >= 0);
638 	pr_err("auth protocol '%s' authorization to %s failed: %d\n",
639 	       ceph_auth_proto_name(ac->protocol),
640 	       ceph_entity_type_name(peer_type), result);
641 
642 	if (ac->ops->invalidate_authorizer)
643 		ac->ops->invalidate_authorizer(ac, peer_type);
644 
645 	mutex_unlock(&ac->mutex);
646 	return true;
647 
648 not_allowed:
649 	mutex_unlock(&ac->mutex);
650 	return false;
651 }
652 EXPORT_SYMBOL(ceph_auth_handle_bad_authorizer);
653