xref: /linux/net/ceph/auth_x.c (revision aa668632ae8c25ffc2d94c865af099cca15944b4)
1 
2 #include <linux/ceph/ceph_debug.h>
3 
4 #include <linux/err.h>
5 #include <linux/module.h>
6 #include <linux/random.h>
7 #include <linux/slab.h>
8 
9 #include <linux/ceph/decode.h>
10 #include <linux/ceph/auth.h>
11 #include <linux/ceph/libceph.h>
12 #include <linux/ceph/messenger.h>
13 
14 #include "crypto.h"
15 #include "auth_x.h"
16 #include "auth_x_protocol.h"
17 
18 static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed);
19 
20 static int ceph_x_is_authenticated(struct ceph_auth_client *ac)
21 {
22 	struct ceph_x_info *xi = ac->private;
23 	int need;
24 
25 	ceph_x_validate_tickets(ac, &need);
26 	dout("ceph_x_is_authenticated want=%d need=%d have=%d\n",
27 	     ac->want_keys, need, xi->have_keys);
28 	return (ac->want_keys & xi->have_keys) == ac->want_keys;
29 }
30 
31 static int ceph_x_should_authenticate(struct ceph_auth_client *ac)
32 {
33 	struct ceph_x_info *xi = ac->private;
34 	int need;
35 
36 	ceph_x_validate_tickets(ac, &need);
37 	dout("ceph_x_should_authenticate want=%d need=%d have=%d\n",
38 	     ac->want_keys, need, xi->have_keys);
39 	return need != 0;
40 }
41 
42 static int ceph_x_encrypt_offset(void)
43 {
44 	return sizeof(u32) + sizeof(struct ceph_x_encrypt_header);
45 }
46 
47 static int ceph_x_encrypt_buflen(int ilen)
48 {
49 	return ceph_x_encrypt_offset() + ilen + 16;
50 }
51 
52 static int ceph_x_encrypt(struct ceph_crypto_key *secret, void *buf,
53 			  int buf_len, int plaintext_len)
54 {
55 	struct ceph_x_encrypt_header *hdr = buf + sizeof(u32);
56 	int ciphertext_len;
57 	int ret;
58 
59 	hdr->struct_v = 1;
60 	hdr->magic = cpu_to_le64(CEPHX_ENC_MAGIC);
61 
62 	ret = ceph_crypt(secret, true, buf + sizeof(u32), buf_len - sizeof(u32),
63 			 plaintext_len + sizeof(struct ceph_x_encrypt_header),
64 			 &ciphertext_len);
65 	if (ret)
66 		return ret;
67 
68 	ceph_encode_32(&buf, ciphertext_len);
69 	return sizeof(u32) + ciphertext_len;
70 }
71 
72 static int ceph_x_decrypt(struct ceph_crypto_key *secret, void **p, void *end)
73 {
74 	struct ceph_x_encrypt_header *hdr = *p + sizeof(u32);
75 	int ciphertext_len, plaintext_len;
76 	int ret;
77 
78 	ceph_decode_32_safe(p, end, ciphertext_len, e_inval);
79 	ceph_decode_need(p, end, ciphertext_len, e_inval);
80 
81 	ret = ceph_crypt(secret, false, *p, end - *p, ciphertext_len,
82 			 &plaintext_len);
83 	if (ret)
84 		return ret;
85 
86 	if (hdr->struct_v != 1 || le64_to_cpu(hdr->magic) != CEPHX_ENC_MAGIC)
87 		return -EPERM;
88 
89 	*p += ciphertext_len;
90 	return plaintext_len - sizeof(struct ceph_x_encrypt_header);
91 
92 e_inval:
93 	return -EINVAL;
94 }
95 
96 /*
97  * get existing (or insert new) ticket handler
98  */
99 static struct ceph_x_ticket_handler *
100 get_ticket_handler(struct ceph_auth_client *ac, int service)
101 {
102 	struct ceph_x_ticket_handler *th;
103 	struct ceph_x_info *xi = ac->private;
104 	struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node;
105 
106 	while (*p) {
107 		parent = *p;
108 		th = rb_entry(parent, struct ceph_x_ticket_handler, node);
109 		if (service < th->service)
110 			p = &(*p)->rb_left;
111 		else if (service > th->service)
112 			p = &(*p)->rb_right;
113 		else
114 			return th;
115 	}
116 
117 	/* add it */
118 	th = kzalloc(sizeof(*th), GFP_NOFS);
119 	if (!th)
120 		return ERR_PTR(-ENOMEM);
121 	th->service = service;
122 	rb_link_node(&th->node, parent, p);
123 	rb_insert_color(&th->node, &xi->ticket_handlers);
124 	return th;
125 }
126 
127 static void remove_ticket_handler(struct ceph_auth_client *ac,
128 				  struct ceph_x_ticket_handler *th)
129 {
130 	struct ceph_x_info *xi = ac->private;
131 
132 	dout("remove_ticket_handler %p %d\n", th, th->service);
133 	rb_erase(&th->node, &xi->ticket_handlers);
134 	ceph_crypto_key_destroy(&th->session_key);
135 	if (th->ticket_blob)
136 		ceph_buffer_put(th->ticket_blob);
137 	kfree(th);
138 }
139 
140 static int process_one_ticket(struct ceph_auth_client *ac,
141 			      struct ceph_crypto_key *secret,
142 			      void **p, void *end)
143 {
144 	struct ceph_x_info *xi = ac->private;
145 	int type;
146 	u8 tkt_struct_v, blob_struct_v;
147 	struct ceph_x_ticket_handler *th;
148 	void *dp, *dend;
149 	int dlen;
150 	char is_enc;
151 	struct timespec validity;
152 	void *tp, *tpend;
153 	void **ptp;
154 	struct ceph_crypto_key new_session_key = { 0 };
155 	struct ceph_buffer *new_ticket_blob;
156 	unsigned long new_expires, new_renew_after;
157 	u64 new_secret_id;
158 	int ret;
159 
160 	ceph_decode_need(p, end, sizeof(u32) + 1, bad);
161 
162 	type = ceph_decode_32(p);
163 	dout(" ticket type %d %s\n", type, ceph_entity_type_name(type));
164 
165 	tkt_struct_v = ceph_decode_8(p);
166 	if (tkt_struct_v != 1)
167 		goto bad;
168 
169 	th = get_ticket_handler(ac, type);
170 	if (IS_ERR(th)) {
171 		ret = PTR_ERR(th);
172 		goto out;
173 	}
174 
175 	/* blob for me */
176 	dp = *p + ceph_x_encrypt_offset();
177 	ret = ceph_x_decrypt(secret, p, end);
178 	if (ret < 0)
179 		goto out;
180 	dout(" decrypted %d bytes\n", ret);
181 	dend = dp + ret;
182 
183 	tkt_struct_v = ceph_decode_8(&dp);
184 	if (tkt_struct_v != 1)
185 		goto bad;
186 
187 	ret = ceph_crypto_key_decode(&new_session_key, &dp, dend);
188 	if (ret)
189 		goto out;
190 
191 	ceph_decode_timespec(&validity, dp);
192 	dp += sizeof(struct ceph_timespec);
193 	new_expires = get_seconds() + validity.tv_sec;
194 	new_renew_after = new_expires - (validity.tv_sec / 4);
195 	dout(" expires=%lu renew_after=%lu\n", new_expires,
196 	     new_renew_after);
197 
198 	/* ticket blob for service */
199 	ceph_decode_8_safe(p, end, is_enc, bad);
200 	if (is_enc) {
201 		/* encrypted */
202 		tp = *p + ceph_x_encrypt_offset();
203 		ret = ceph_x_decrypt(&th->session_key, p, end);
204 		if (ret < 0)
205 			goto out;
206 		dout(" encrypted ticket, decrypted %d bytes\n", ret);
207 		ptp = &tp;
208 		tpend = tp + ret;
209 	} else {
210 		/* unencrypted */
211 		ptp = p;
212 		tpend = end;
213 	}
214 	ceph_decode_32_safe(ptp, tpend, dlen, bad);
215 	dout(" ticket blob is %d bytes\n", dlen);
216 	ceph_decode_need(ptp, tpend, 1 + sizeof(u64), bad);
217 	blob_struct_v = ceph_decode_8(ptp);
218 	if (blob_struct_v != 1)
219 		goto bad;
220 
221 	new_secret_id = ceph_decode_64(ptp);
222 	ret = ceph_decode_buffer(&new_ticket_blob, ptp, tpend);
223 	if (ret)
224 		goto out;
225 
226 	/* all is well, update our ticket */
227 	ceph_crypto_key_destroy(&th->session_key);
228 	if (th->ticket_blob)
229 		ceph_buffer_put(th->ticket_blob);
230 	th->session_key = new_session_key;
231 	th->ticket_blob = new_ticket_blob;
232 	th->secret_id = new_secret_id;
233 	th->expires = new_expires;
234 	th->renew_after = new_renew_after;
235 	th->have_key = true;
236 	dout(" got ticket service %d (%s) secret_id %lld len %d\n",
237 	     type, ceph_entity_type_name(type), th->secret_id,
238 	     (int)th->ticket_blob->vec.iov_len);
239 	xi->have_keys |= th->service;
240 	return 0;
241 
242 bad:
243 	ret = -EINVAL;
244 out:
245 	ceph_crypto_key_destroy(&new_session_key);
246 	return ret;
247 }
248 
249 static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac,
250 				    struct ceph_crypto_key *secret,
251 				    void *buf, void *end)
252 {
253 	void *p = buf;
254 	u8 reply_struct_v;
255 	u32 num;
256 	int ret;
257 
258 	ceph_decode_8_safe(&p, end, reply_struct_v, bad);
259 	if (reply_struct_v != 1)
260 		return -EINVAL;
261 
262 	ceph_decode_32_safe(&p, end, num, bad);
263 	dout("%d tickets\n", num);
264 
265 	while (num--) {
266 		ret = process_one_ticket(ac, secret, &p, end);
267 		if (ret)
268 			return ret;
269 	}
270 
271 	return 0;
272 
273 bad:
274 	return -EINVAL;
275 }
276 
277 static void ceph_x_authorizer_cleanup(struct ceph_x_authorizer *au)
278 {
279 	ceph_crypto_key_destroy(&au->session_key);
280 	if (au->buf) {
281 		ceph_buffer_put(au->buf);
282 		au->buf = NULL;
283 	}
284 }
285 
286 static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
287 				   struct ceph_x_ticket_handler *th,
288 				   struct ceph_x_authorizer *au)
289 {
290 	int maxlen;
291 	struct ceph_x_authorize_a *msg_a;
292 	struct ceph_x_authorize_b *msg_b;
293 	void *p, *end;
294 	int ret;
295 	int ticket_blob_len =
296 		(th->ticket_blob ? th->ticket_blob->vec.iov_len : 0);
297 
298 	dout("build_authorizer for %s %p\n",
299 	     ceph_entity_type_name(th->service), au);
300 
301 	ceph_crypto_key_destroy(&au->session_key);
302 	ret = ceph_crypto_key_clone(&au->session_key, &th->session_key);
303 	if (ret)
304 		goto out_au;
305 
306 	maxlen = sizeof(*msg_a) + ticket_blob_len +
307 		ceph_x_encrypt_buflen(sizeof(*msg_b));
308 	dout("  need len %d\n", maxlen);
309 	if (au->buf && au->buf->alloc_len < maxlen) {
310 		ceph_buffer_put(au->buf);
311 		au->buf = NULL;
312 	}
313 	if (!au->buf) {
314 		au->buf = ceph_buffer_new(maxlen, GFP_NOFS);
315 		if (!au->buf) {
316 			ret = -ENOMEM;
317 			goto out_au;
318 		}
319 	}
320 	au->service = th->service;
321 	au->secret_id = th->secret_id;
322 
323 	msg_a = au->buf->vec.iov_base;
324 	msg_a->struct_v = 1;
325 	msg_a->global_id = cpu_to_le64(ac->global_id);
326 	msg_a->service_id = cpu_to_le32(th->service);
327 	msg_a->ticket_blob.struct_v = 1;
328 	msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id);
329 	msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len);
330 	if (ticket_blob_len) {
331 		memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base,
332 		       th->ticket_blob->vec.iov_len);
333 	}
334 	dout(" th %p secret_id %lld %lld\n", th, th->secret_id,
335 	     le64_to_cpu(msg_a->ticket_blob.secret_id));
336 
337 	p = msg_a + 1;
338 	p += ticket_blob_len;
339 	end = au->buf->vec.iov_base + au->buf->vec.iov_len;
340 
341 	msg_b = p + ceph_x_encrypt_offset();
342 	msg_b->struct_v = 1;
343 	get_random_bytes(&au->nonce, sizeof(au->nonce));
344 	msg_b->nonce = cpu_to_le64(au->nonce);
345 	ret = ceph_x_encrypt(&au->session_key, p, end - p, sizeof(*msg_b));
346 	if (ret < 0)
347 		goto out_au;
348 
349 	p += ret;
350 	WARN_ON(p > end);
351 	au->buf->vec.iov_len = p - au->buf->vec.iov_base;
352 	dout(" built authorizer nonce %llx len %d\n", au->nonce,
353 	     (int)au->buf->vec.iov_len);
354 	return 0;
355 
356 out_au:
357 	ceph_x_authorizer_cleanup(au);
358 	return ret;
359 }
360 
361 static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th,
362 				void **p, void *end)
363 {
364 	ceph_decode_need(p, end, 1 + sizeof(u64), bad);
365 	ceph_encode_8(p, 1);
366 	ceph_encode_64(p, th->secret_id);
367 	if (th->ticket_blob) {
368 		const char *buf = th->ticket_blob->vec.iov_base;
369 		u32 len = th->ticket_blob->vec.iov_len;
370 
371 		ceph_encode_32_safe(p, end, len, bad);
372 		ceph_encode_copy_safe(p, end, buf, len, bad);
373 	} else {
374 		ceph_encode_32_safe(p, end, 0, bad);
375 	}
376 
377 	return 0;
378 bad:
379 	return -ERANGE;
380 }
381 
382 static bool need_key(struct ceph_x_ticket_handler *th)
383 {
384 	if (!th->have_key)
385 		return true;
386 
387 	return get_seconds() >= th->renew_after;
388 }
389 
390 static bool have_key(struct ceph_x_ticket_handler *th)
391 {
392 	if (th->have_key) {
393 		if (get_seconds() >= th->expires)
394 			th->have_key = false;
395 	}
396 
397 	return th->have_key;
398 }
399 
400 static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed)
401 {
402 	int want = ac->want_keys;
403 	struct ceph_x_info *xi = ac->private;
404 	int service;
405 
406 	*pneed = ac->want_keys & ~(xi->have_keys);
407 
408 	for (service = 1; service <= want; service <<= 1) {
409 		struct ceph_x_ticket_handler *th;
410 
411 		if (!(ac->want_keys & service))
412 			continue;
413 
414 		if (*pneed & service)
415 			continue;
416 
417 		th = get_ticket_handler(ac, service);
418 		if (IS_ERR(th)) {
419 			*pneed |= service;
420 			continue;
421 		}
422 
423 		if (need_key(th))
424 			*pneed |= service;
425 		if (!have_key(th))
426 			xi->have_keys &= ~service;
427 	}
428 }
429 
430 static int ceph_x_build_request(struct ceph_auth_client *ac,
431 				void *buf, void *end)
432 {
433 	struct ceph_x_info *xi = ac->private;
434 	int need;
435 	struct ceph_x_request_header *head = buf;
436 	int ret;
437 	struct ceph_x_ticket_handler *th =
438 		get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
439 
440 	if (IS_ERR(th))
441 		return PTR_ERR(th);
442 
443 	ceph_x_validate_tickets(ac, &need);
444 
445 	dout("build_request want %x have %x need %x\n",
446 	     ac->want_keys, xi->have_keys, need);
447 
448 	if (need & CEPH_ENTITY_TYPE_AUTH) {
449 		struct ceph_x_authenticate *auth = (void *)(head + 1);
450 		void *p = auth + 1;
451 		void *enc_buf = xi->auth_authorizer.enc_buf;
452 		struct ceph_x_challenge_blob *blob = enc_buf +
453 							ceph_x_encrypt_offset();
454 		u64 *u;
455 
456 		if (p > end)
457 			return -ERANGE;
458 
459 		dout(" get_auth_session_key\n");
460 		head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY);
461 
462 		/* encrypt and hash */
463 		get_random_bytes(&auth->client_challenge, sizeof(u64));
464 		blob->client_challenge = auth->client_challenge;
465 		blob->server_challenge = cpu_to_le64(xi->server_challenge);
466 		ret = ceph_x_encrypt(&xi->secret, enc_buf, CEPHX_AU_ENC_BUF_LEN,
467 				     sizeof(*blob));
468 		if (ret < 0)
469 			return ret;
470 
471 		auth->struct_v = 1;
472 		auth->key = 0;
473 		for (u = (u64 *)enc_buf; u + 1 <= (u64 *)(enc_buf + ret); u++)
474 			auth->key ^= *(__le64 *)u;
475 		dout(" server_challenge %llx client_challenge %llx key %llx\n",
476 		     xi->server_challenge, le64_to_cpu(auth->client_challenge),
477 		     le64_to_cpu(auth->key));
478 
479 		/* now encode the old ticket if exists */
480 		ret = ceph_x_encode_ticket(th, &p, end);
481 		if (ret < 0)
482 			return ret;
483 
484 		return p - buf;
485 	}
486 
487 	if (need) {
488 		void *p = head + 1;
489 		struct ceph_x_service_ticket_request *req;
490 
491 		if (p > end)
492 			return -ERANGE;
493 		head->op = cpu_to_le16(CEPHX_GET_PRINCIPAL_SESSION_KEY);
494 
495 		ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer);
496 		if (ret)
497 			return ret;
498 		ceph_encode_copy(&p, xi->auth_authorizer.buf->vec.iov_base,
499 				 xi->auth_authorizer.buf->vec.iov_len);
500 
501 		req = p;
502 		req->keys = cpu_to_le32(need);
503 		p += sizeof(*req);
504 		return p - buf;
505 	}
506 
507 	return 0;
508 }
509 
510 static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result,
511 			       void *buf, void *end)
512 {
513 	struct ceph_x_info *xi = ac->private;
514 	struct ceph_x_reply_header *head = buf;
515 	struct ceph_x_ticket_handler *th;
516 	int len = end - buf;
517 	int op;
518 	int ret;
519 
520 	if (result)
521 		return result;  /* XXX hmm? */
522 
523 	if (xi->starting) {
524 		/* it's a hello */
525 		struct ceph_x_server_challenge *sc = buf;
526 
527 		if (len != sizeof(*sc))
528 			return -EINVAL;
529 		xi->server_challenge = le64_to_cpu(sc->server_challenge);
530 		dout("handle_reply got server challenge %llx\n",
531 		     xi->server_challenge);
532 		xi->starting = false;
533 		xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH;
534 		return -EAGAIN;
535 	}
536 
537 	op = le16_to_cpu(head->op);
538 	result = le32_to_cpu(head->result);
539 	dout("handle_reply op %d result %d\n", op, result);
540 	switch (op) {
541 	case CEPHX_GET_AUTH_SESSION_KEY:
542 		/* verify auth key */
543 		ret = ceph_x_proc_ticket_reply(ac, &xi->secret,
544 					       buf + sizeof(*head), end);
545 		break;
546 
547 	case CEPHX_GET_PRINCIPAL_SESSION_KEY:
548 		th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
549 		if (IS_ERR(th))
550 			return PTR_ERR(th);
551 		ret = ceph_x_proc_ticket_reply(ac, &th->session_key,
552 					       buf + sizeof(*head), end);
553 		break;
554 
555 	default:
556 		return -EINVAL;
557 	}
558 	if (ret)
559 		return ret;
560 	if (ac->want_keys == xi->have_keys)
561 		return 0;
562 	return -EAGAIN;
563 }
564 
565 static void ceph_x_destroy_authorizer(struct ceph_authorizer *a)
566 {
567 	struct ceph_x_authorizer *au = (void *)a;
568 
569 	ceph_x_authorizer_cleanup(au);
570 	kfree(au);
571 }
572 
573 static int ceph_x_create_authorizer(
574 	struct ceph_auth_client *ac, int peer_type,
575 	struct ceph_auth_handshake *auth)
576 {
577 	struct ceph_x_authorizer *au;
578 	struct ceph_x_ticket_handler *th;
579 	int ret;
580 
581 	th = get_ticket_handler(ac, peer_type);
582 	if (IS_ERR(th))
583 		return PTR_ERR(th);
584 
585 	au = kzalloc(sizeof(*au), GFP_NOFS);
586 	if (!au)
587 		return -ENOMEM;
588 
589 	au->base.destroy = ceph_x_destroy_authorizer;
590 
591 	ret = ceph_x_build_authorizer(ac, th, au);
592 	if (ret) {
593 		kfree(au);
594 		return ret;
595 	}
596 
597 	auth->authorizer = (struct ceph_authorizer *) au;
598 	auth->authorizer_buf = au->buf->vec.iov_base;
599 	auth->authorizer_buf_len = au->buf->vec.iov_len;
600 	auth->authorizer_reply_buf = au->enc_buf;
601 	auth->authorizer_reply_buf_len = CEPHX_AU_ENC_BUF_LEN;
602 	auth->sign_message = ac->ops->sign_message;
603 	auth->check_message_signature = ac->ops->check_message_signature;
604 
605 	return 0;
606 }
607 
608 static int ceph_x_update_authorizer(
609 	struct ceph_auth_client *ac, int peer_type,
610 	struct ceph_auth_handshake *auth)
611 {
612 	struct ceph_x_authorizer *au;
613 	struct ceph_x_ticket_handler *th;
614 
615 	th = get_ticket_handler(ac, peer_type);
616 	if (IS_ERR(th))
617 		return PTR_ERR(th);
618 
619 	au = (struct ceph_x_authorizer *)auth->authorizer;
620 	if (au->secret_id < th->secret_id) {
621 		dout("ceph_x_update_authorizer service %u secret %llu < %llu\n",
622 		     au->service, au->secret_id, th->secret_id);
623 		return ceph_x_build_authorizer(ac, th, au);
624 	}
625 	return 0;
626 }
627 
628 static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac,
629 					  struct ceph_authorizer *a)
630 {
631 	struct ceph_x_authorizer *au = (void *)a;
632 	void *p = au->enc_buf;
633 	struct ceph_x_authorize_reply *reply = p + ceph_x_encrypt_offset();
634 	int ret;
635 
636 	ret = ceph_x_decrypt(&au->session_key, &p, p + CEPHX_AU_ENC_BUF_LEN);
637 	if (ret < 0)
638 		return ret;
639 	if (ret != sizeof(*reply))
640 		return -EPERM;
641 
642 	if (au->nonce + 1 != le64_to_cpu(reply->nonce_plus_one))
643 		ret = -EPERM;
644 	else
645 		ret = 0;
646 	dout("verify_authorizer_reply nonce %llx got %llx ret %d\n",
647 	     au->nonce, le64_to_cpu(reply->nonce_plus_one), ret);
648 	return ret;
649 }
650 
651 static void ceph_x_reset(struct ceph_auth_client *ac)
652 {
653 	struct ceph_x_info *xi = ac->private;
654 
655 	dout("reset\n");
656 	xi->starting = true;
657 	xi->server_challenge = 0;
658 }
659 
660 static void ceph_x_destroy(struct ceph_auth_client *ac)
661 {
662 	struct ceph_x_info *xi = ac->private;
663 	struct rb_node *p;
664 
665 	dout("ceph_x_destroy %p\n", ac);
666 	ceph_crypto_key_destroy(&xi->secret);
667 
668 	while ((p = rb_first(&xi->ticket_handlers)) != NULL) {
669 		struct ceph_x_ticket_handler *th =
670 			rb_entry(p, struct ceph_x_ticket_handler, node);
671 		remove_ticket_handler(ac, th);
672 	}
673 
674 	ceph_x_authorizer_cleanup(&xi->auth_authorizer);
675 
676 	kfree(ac->private);
677 	ac->private = NULL;
678 }
679 
680 static void invalidate_ticket(struct ceph_auth_client *ac, int peer_type)
681 {
682 	struct ceph_x_ticket_handler *th;
683 
684 	th = get_ticket_handler(ac, peer_type);
685 	if (!IS_ERR(th))
686 		th->have_key = false;
687 }
688 
689 static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac,
690 					 int peer_type)
691 {
692 	/*
693 	 * We are to invalidate a service ticket in the hopes of
694 	 * getting a new, hopefully more valid, one.  But, we won't get
695 	 * it unless our AUTH ticket is good, so invalidate AUTH ticket
696 	 * as well, just in case.
697 	 */
698 	invalidate_ticket(ac, peer_type);
699 	invalidate_ticket(ac, CEPH_ENTITY_TYPE_AUTH);
700 }
701 
702 static int calc_signature(struct ceph_x_authorizer *au, struct ceph_msg *msg,
703 			  __le64 *psig)
704 {
705 	void *enc_buf = au->enc_buf;
706 	struct {
707 		__le32 len;
708 		__le32 header_crc;
709 		__le32 front_crc;
710 		__le32 middle_crc;
711 		__le32 data_crc;
712 	} __packed *sigblock = enc_buf + ceph_x_encrypt_offset();
713 	int ret;
714 
715 	sigblock->len = cpu_to_le32(4*sizeof(u32));
716 	sigblock->header_crc = msg->hdr.crc;
717 	sigblock->front_crc = msg->footer.front_crc;
718 	sigblock->middle_crc = msg->footer.middle_crc;
719 	sigblock->data_crc =  msg->footer.data_crc;
720 	ret = ceph_x_encrypt(&au->session_key, enc_buf, CEPHX_AU_ENC_BUF_LEN,
721 			     sizeof(*sigblock));
722 	if (ret < 0)
723 		return ret;
724 
725 	*psig = *(__le64 *)(enc_buf + sizeof(u32));
726 	return 0;
727 }
728 
729 static int ceph_x_sign_message(struct ceph_auth_handshake *auth,
730 			       struct ceph_msg *msg)
731 {
732 	__le64 sig;
733 	int ret;
734 
735 	if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
736 		return 0;
737 
738 	ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer,
739 			     msg, &sig);
740 	if (ret)
741 		return ret;
742 
743 	msg->footer.sig = sig;
744 	msg->footer.flags |= CEPH_MSG_FOOTER_SIGNED;
745 	return 0;
746 }
747 
748 static int ceph_x_check_message_signature(struct ceph_auth_handshake *auth,
749 					  struct ceph_msg *msg)
750 {
751 	__le64 sig_check;
752 	int ret;
753 
754 	if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
755 		return 0;
756 
757 	ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer,
758 			     msg, &sig_check);
759 	if (ret)
760 		return ret;
761 	if (sig_check == msg->footer.sig)
762 		return 0;
763 	if (msg->footer.flags & CEPH_MSG_FOOTER_SIGNED)
764 		dout("ceph_x_check_message_signature %p has signature %llx "
765 		     "expect %llx\n", msg, msg->footer.sig, sig_check);
766 	else
767 		dout("ceph_x_check_message_signature %p sender did not set "
768 		     "CEPH_MSG_FOOTER_SIGNED\n", msg);
769 	return -EBADMSG;
770 }
771 
772 static const struct ceph_auth_client_ops ceph_x_ops = {
773 	.name = "x",
774 	.is_authenticated = ceph_x_is_authenticated,
775 	.should_authenticate = ceph_x_should_authenticate,
776 	.build_request = ceph_x_build_request,
777 	.handle_reply = ceph_x_handle_reply,
778 	.create_authorizer = ceph_x_create_authorizer,
779 	.update_authorizer = ceph_x_update_authorizer,
780 	.verify_authorizer_reply = ceph_x_verify_authorizer_reply,
781 	.invalidate_authorizer = ceph_x_invalidate_authorizer,
782 	.reset =  ceph_x_reset,
783 	.destroy = ceph_x_destroy,
784 	.sign_message = ceph_x_sign_message,
785 	.check_message_signature = ceph_x_check_message_signature,
786 };
787 
788 
789 int ceph_x_init(struct ceph_auth_client *ac)
790 {
791 	struct ceph_x_info *xi;
792 	int ret;
793 
794 	dout("ceph_x_init %p\n", ac);
795 	ret = -ENOMEM;
796 	xi = kzalloc(sizeof(*xi), GFP_NOFS);
797 	if (!xi)
798 		goto out;
799 
800 	ret = -EINVAL;
801 	if (!ac->key) {
802 		pr_err("no secret set (for auth_x protocol)\n");
803 		goto out_nomem;
804 	}
805 
806 	ret = ceph_crypto_key_clone(&xi->secret, ac->key);
807 	if (ret < 0) {
808 		pr_err("cannot clone key: %d\n", ret);
809 		goto out_nomem;
810 	}
811 
812 	xi->starting = true;
813 	xi->ticket_handlers = RB_ROOT;
814 
815 	ac->protocol = CEPH_AUTH_CEPHX;
816 	ac->private = xi;
817 	ac->ops = &ceph_x_ops;
818 	return 0;
819 
820 out_nomem:
821 	kfree(xi);
822 out:
823 	return ret;
824 }
825 
826 
827