libceph: eliminate unnecessary allocation in process_one_ticket()
[sfrench/cifs-2.6.git] / net / ceph / auth_x.c
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
12 #include "crypto.h"
13 #include "auth_x.h"
14 #include "auth_x_protocol.h"
15
16 static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed);
17
18 static int ceph_x_is_authenticated(struct ceph_auth_client *ac)
19 {
20         struct ceph_x_info *xi = ac->private;
21         int need;
22
23         ceph_x_validate_tickets(ac, &need);
24         dout("ceph_x_is_authenticated want=%d need=%d have=%d\n",
25              ac->want_keys, need, xi->have_keys);
26         return (ac->want_keys & xi->have_keys) == ac->want_keys;
27 }
28
29 static int ceph_x_should_authenticate(struct ceph_auth_client *ac)
30 {
31         struct ceph_x_info *xi = ac->private;
32         int need;
33
34         ceph_x_validate_tickets(ac, &need);
35         dout("ceph_x_should_authenticate want=%d need=%d have=%d\n",
36              ac->want_keys, need, xi->have_keys);
37         return need != 0;
38 }
39
40 static int ceph_x_encrypt_buflen(int ilen)
41 {
42         return sizeof(struct ceph_x_encrypt_header) + ilen + 16 +
43                 sizeof(u32);
44 }
45
46 static int ceph_x_encrypt(struct ceph_crypto_key *secret,
47                           void *ibuf, int ilen, void *obuf, size_t olen)
48 {
49         struct ceph_x_encrypt_header head = {
50                 .struct_v = 1,
51                 .magic = cpu_to_le64(CEPHX_ENC_MAGIC)
52         };
53         size_t len = olen - sizeof(u32);
54         int ret;
55
56         ret = ceph_encrypt2(secret, obuf + sizeof(u32), &len,
57                             &head, sizeof(head), ibuf, ilen);
58         if (ret)
59                 return ret;
60         ceph_encode_32(&obuf, len);
61         return len + sizeof(u32);
62 }
63
64 static int ceph_x_decrypt(struct ceph_crypto_key *secret,
65                           void **p, void *end, void **obuf, size_t olen)
66 {
67         struct ceph_x_encrypt_header head;
68         size_t head_len = sizeof(head);
69         int len, ret;
70
71         len = ceph_decode_32(p);
72         if (*p + len > end)
73                 return -EINVAL;
74
75         dout("ceph_x_decrypt len %d\n", len);
76         if (*obuf == NULL) {
77                 *obuf = kmalloc(len, GFP_NOFS);
78                 if (!*obuf)
79                         return -ENOMEM;
80                 olen = len;
81         }
82
83         ret = ceph_decrypt2(secret, &head, &head_len, *obuf, &olen, *p, len);
84         if (ret)
85                 return ret;
86         if (head.struct_v != 1 || le64_to_cpu(head.magic) != CEPHX_ENC_MAGIC)
87                 return -EPERM;
88         *p += len;
89         return olen;
90 }
91
92 /*
93  * get existing (or insert new) ticket handler
94  */
95 static struct ceph_x_ticket_handler *
96 get_ticket_handler(struct ceph_auth_client *ac, int service)
97 {
98         struct ceph_x_ticket_handler *th;
99         struct ceph_x_info *xi = ac->private;
100         struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node;
101
102         while (*p) {
103                 parent = *p;
104                 th = rb_entry(parent, struct ceph_x_ticket_handler, node);
105                 if (service < th->service)
106                         p = &(*p)->rb_left;
107                 else if (service > th->service)
108                         p = &(*p)->rb_right;
109                 else
110                         return th;
111         }
112
113         /* add it */
114         th = kzalloc(sizeof(*th), GFP_NOFS);
115         if (!th)
116                 return ERR_PTR(-ENOMEM);
117         th->service = service;
118         rb_link_node(&th->node, parent, p);
119         rb_insert_color(&th->node, &xi->ticket_handlers);
120         return th;
121 }
122
123 static void remove_ticket_handler(struct ceph_auth_client *ac,
124                                   struct ceph_x_ticket_handler *th)
125 {
126         struct ceph_x_info *xi = ac->private;
127
128         dout("remove_ticket_handler %p %d\n", th, th->service);
129         rb_erase(&th->node, &xi->ticket_handlers);
130         ceph_crypto_key_destroy(&th->session_key);
131         if (th->ticket_blob)
132                 ceph_buffer_put(th->ticket_blob);
133         kfree(th);
134 }
135
136 static int process_one_ticket(struct ceph_auth_client *ac,
137                               struct ceph_crypto_key *secret,
138                               void **p, void *end)
139 {
140         struct ceph_x_info *xi = ac->private;
141         int type;
142         u8 tkt_struct_v, blob_struct_v;
143         struct ceph_x_ticket_handler *th;
144         void *dbuf = NULL;
145         void *dp, *dend;
146         int dlen;
147         char is_enc;
148         struct timespec validity;
149         struct ceph_crypto_key old_key;
150         void *ticket_buf = NULL;
151         void *tp, *tpend;
152         void **ptp;
153         struct ceph_timespec new_validity;
154         struct ceph_crypto_key new_session_key;
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         dlen = ceph_x_decrypt(secret, p, end, &dbuf, 0);
177         if (dlen <= 0) {
178                 ret = dlen;
179                 goto out;
180         }
181         dout(" decrypted %d bytes\n", dlen);
182         dp = dbuf;
183         dend = dp + dlen;
184
185         tkt_struct_v = ceph_decode_8(&dp);
186         if (tkt_struct_v != 1)
187                 goto bad;
188
189         memcpy(&old_key, &th->session_key, sizeof(old_key));
190         ret = ceph_crypto_key_decode(&new_session_key, &dp, dend);
191         if (ret)
192                 goto out;
193
194         ceph_decode_copy(&dp, &new_validity, sizeof(new_validity));
195         ceph_decode_timespec(&validity, &new_validity);
196         new_expires = get_seconds() + validity.tv_sec;
197         new_renew_after = new_expires - (validity.tv_sec / 4);
198         dout(" expires=%lu renew_after=%lu\n", new_expires,
199              new_renew_after);
200
201         /* ticket blob for service */
202         ceph_decode_8_safe(p, end, is_enc, bad);
203         if (is_enc) {
204                 /* encrypted */
205                 dout(" encrypted ticket\n");
206                 dlen = ceph_x_decrypt(&old_key, p, end, &ticket_buf, 0);
207                 if (dlen < 0) {
208                         ret = dlen;
209                         goto out;
210                 }
211                 tp = ticket_buf;
212                 ptp = &tp;
213                 tpend = *ptp + dlen;
214         } else {
215                 /* unencrypted */
216                 ptp = p;
217                 tpend = end;
218         }
219         ceph_decode_32_safe(ptp, tpend, dlen, bad);
220         dout(" ticket blob is %d bytes\n", dlen);
221         ceph_decode_need(ptp, tpend, 1 + sizeof(u64), bad);
222         blob_struct_v = ceph_decode_8(ptp);
223         new_secret_id = ceph_decode_64(ptp);
224         ret = ceph_decode_buffer(&new_ticket_blob, ptp, tpend);
225         if (ret)
226                 goto out;
227
228         /* all is well, update our ticket */
229         ceph_crypto_key_destroy(&th->session_key);
230         if (th->ticket_blob)
231                 ceph_buffer_put(th->ticket_blob);
232         th->session_key = new_session_key;
233         th->ticket_blob = new_ticket_blob;
234         th->validity = new_validity;
235         th->secret_id = new_secret_id;
236         th->expires = new_expires;
237         th->renew_after = new_renew_after;
238         dout(" got ticket service %d (%s) secret_id %lld len %d\n",
239              type, ceph_entity_type_name(type), th->secret_id,
240              (int)th->ticket_blob->vec.iov_len);
241         xi->have_keys |= th->service;
242
243 out:
244         kfree(ticket_buf);
245         kfree(dbuf);
246         return ret;
247
248 bad:
249         ret = -EINVAL;
250         goto out;
251 }
252
253 static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac,
254                                     struct ceph_crypto_key *secret,
255                                     void *buf, void *end)
256 {
257         void *p = buf;
258         u8 reply_struct_v;
259         u32 num;
260         int ret;
261
262         ceph_decode_8_safe(&p, end, reply_struct_v, bad);
263         if (reply_struct_v != 1)
264                 return -EINVAL;
265
266         ceph_decode_32_safe(&p, end, num, bad);
267         dout("%d tickets\n", num);
268
269         while (num--) {
270                 ret = process_one_ticket(ac, secret, &p, end);
271                 if (ret)
272                         return ret;
273         }
274
275         return 0;
276
277 bad:
278         return -EINVAL;
279 }
280
281 static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
282                                    struct ceph_x_ticket_handler *th,
283                                    struct ceph_x_authorizer *au)
284 {
285         int maxlen;
286         struct ceph_x_authorize_a *msg_a;
287         struct ceph_x_authorize_b msg_b;
288         void *p, *end;
289         int ret;
290         int ticket_blob_len =
291                 (th->ticket_blob ? th->ticket_blob->vec.iov_len : 0);
292
293         dout("build_authorizer for %s %p\n",
294              ceph_entity_type_name(th->service), au);
295
296         maxlen = sizeof(*msg_a) + sizeof(msg_b) +
297                 ceph_x_encrypt_buflen(ticket_blob_len);
298         dout("  need len %d\n", maxlen);
299         if (au->buf && au->buf->alloc_len < maxlen) {
300                 ceph_buffer_put(au->buf);
301                 au->buf = NULL;
302         }
303         if (!au->buf) {
304                 au->buf = ceph_buffer_new(maxlen, GFP_NOFS);
305                 if (!au->buf)
306                         return -ENOMEM;
307         }
308         au->service = th->service;
309         au->secret_id = th->secret_id;
310
311         msg_a = au->buf->vec.iov_base;
312         msg_a->struct_v = 1;
313         msg_a->global_id = cpu_to_le64(ac->global_id);
314         msg_a->service_id = cpu_to_le32(th->service);
315         msg_a->ticket_blob.struct_v = 1;
316         msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id);
317         msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len);
318         if (ticket_blob_len) {
319                 memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base,
320                        th->ticket_blob->vec.iov_len);
321         }
322         dout(" th %p secret_id %lld %lld\n", th, th->secret_id,
323              le64_to_cpu(msg_a->ticket_blob.secret_id));
324
325         p = msg_a + 1;
326         p += ticket_blob_len;
327         end = au->buf->vec.iov_base + au->buf->vec.iov_len;
328
329         get_random_bytes(&au->nonce, sizeof(au->nonce));
330         msg_b.struct_v = 1;
331         msg_b.nonce = cpu_to_le64(au->nonce);
332         ret = ceph_x_encrypt(&th->session_key, &msg_b, sizeof(msg_b),
333                              p, end - p);
334         if (ret < 0)
335                 goto out_buf;
336         p += ret;
337         au->buf->vec.iov_len = p - au->buf->vec.iov_base;
338         dout(" built authorizer nonce %llx len %d\n", au->nonce,
339              (int)au->buf->vec.iov_len);
340         BUG_ON(au->buf->vec.iov_len > maxlen);
341         return 0;
342
343 out_buf:
344         ceph_buffer_put(au->buf);
345         au->buf = NULL;
346         return ret;
347 }
348
349 static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th,
350                                 void **p, void *end)
351 {
352         ceph_decode_need(p, end, 1 + sizeof(u64), bad);
353         ceph_encode_8(p, 1);
354         ceph_encode_64(p, th->secret_id);
355         if (th->ticket_blob) {
356                 const char *buf = th->ticket_blob->vec.iov_base;
357                 u32 len = th->ticket_blob->vec.iov_len;
358
359                 ceph_encode_32_safe(p, end, len, bad);
360                 ceph_encode_copy_safe(p, end, buf, len, bad);
361         } else {
362                 ceph_encode_32_safe(p, end, 0, bad);
363         }
364
365         return 0;
366 bad:
367         return -ERANGE;
368 }
369
370 static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed)
371 {
372         int want = ac->want_keys;
373         struct ceph_x_info *xi = ac->private;
374         int service;
375
376         *pneed = ac->want_keys & ~(xi->have_keys);
377
378         for (service = 1; service <= want; service <<= 1) {
379                 struct ceph_x_ticket_handler *th;
380
381                 if (!(ac->want_keys & service))
382                         continue;
383
384                 if (*pneed & service)
385                         continue;
386
387                 th = get_ticket_handler(ac, service);
388
389                 if (IS_ERR(th)) {
390                         *pneed |= service;
391                         continue;
392                 }
393
394                 if (get_seconds() >= th->renew_after)
395                         *pneed |= service;
396                 if (get_seconds() >= th->expires)
397                         xi->have_keys &= ~service;
398         }
399 }
400
401
402 static int ceph_x_build_request(struct ceph_auth_client *ac,
403                                 void *buf, void *end)
404 {
405         struct ceph_x_info *xi = ac->private;
406         int need;
407         struct ceph_x_request_header *head = buf;
408         int ret;
409         struct ceph_x_ticket_handler *th =
410                 get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
411
412         if (IS_ERR(th))
413                 return PTR_ERR(th);
414
415         ceph_x_validate_tickets(ac, &need);
416
417         dout("build_request want %x have %x need %x\n",
418              ac->want_keys, xi->have_keys, need);
419
420         if (need & CEPH_ENTITY_TYPE_AUTH) {
421                 struct ceph_x_authenticate *auth = (void *)(head + 1);
422                 void *p = auth + 1;
423                 struct ceph_x_challenge_blob tmp;
424                 char tmp_enc[40];
425                 u64 *u;
426
427                 if (p > end)
428                         return -ERANGE;
429
430                 dout(" get_auth_session_key\n");
431                 head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY);
432
433                 /* encrypt and hash */
434                 get_random_bytes(&auth->client_challenge, sizeof(u64));
435                 tmp.client_challenge = auth->client_challenge;
436                 tmp.server_challenge = cpu_to_le64(xi->server_challenge);
437                 ret = ceph_x_encrypt(&xi->secret, &tmp, sizeof(tmp),
438                                      tmp_enc, sizeof(tmp_enc));
439                 if (ret < 0)
440                         return ret;
441
442                 auth->struct_v = 1;
443                 auth->key = 0;
444                 for (u = (u64 *)tmp_enc; u + 1 <= (u64 *)(tmp_enc + ret); u++)
445                         auth->key ^= *(__le64 *)u;
446                 dout(" server_challenge %llx client_challenge %llx key %llx\n",
447                      xi->server_challenge, le64_to_cpu(auth->client_challenge),
448                      le64_to_cpu(auth->key));
449
450                 /* now encode the old ticket if exists */
451                 ret = ceph_x_encode_ticket(th, &p, end);
452                 if (ret < 0)
453                         return ret;
454
455                 return p - buf;
456         }
457
458         if (need) {
459                 void *p = head + 1;
460                 struct ceph_x_service_ticket_request *req;
461
462                 if (p > end)
463                         return -ERANGE;
464                 head->op = cpu_to_le16(CEPHX_GET_PRINCIPAL_SESSION_KEY);
465
466                 ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer);
467                 if (ret)
468                         return ret;
469                 ceph_encode_copy(&p, xi->auth_authorizer.buf->vec.iov_base,
470                                  xi->auth_authorizer.buf->vec.iov_len);
471
472                 req = p;
473                 req->keys = cpu_to_le32(need);
474                 p += sizeof(*req);
475                 return p - buf;
476         }
477
478         return 0;
479 }
480
481 static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result,
482                                void *buf, void *end)
483 {
484         struct ceph_x_info *xi = ac->private;
485         struct ceph_x_reply_header *head = buf;
486         struct ceph_x_ticket_handler *th;
487         int len = end - buf;
488         int op;
489         int ret;
490
491         if (result)
492                 return result;  /* XXX hmm? */
493
494         if (xi->starting) {
495                 /* it's a hello */
496                 struct ceph_x_server_challenge *sc = buf;
497
498                 if (len != sizeof(*sc))
499                         return -EINVAL;
500                 xi->server_challenge = le64_to_cpu(sc->server_challenge);
501                 dout("handle_reply got server challenge %llx\n",
502                      xi->server_challenge);
503                 xi->starting = false;
504                 xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH;
505                 return -EAGAIN;
506         }
507
508         op = le16_to_cpu(head->op);
509         result = le32_to_cpu(head->result);
510         dout("handle_reply op %d result %d\n", op, result);
511         switch (op) {
512         case CEPHX_GET_AUTH_SESSION_KEY:
513                 /* verify auth key */
514                 ret = ceph_x_proc_ticket_reply(ac, &xi->secret,
515                                                buf + sizeof(*head), end);
516                 break;
517
518         case CEPHX_GET_PRINCIPAL_SESSION_KEY:
519                 th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
520                 if (IS_ERR(th))
521                         return PTR_ERR(th);
522                 ret = ceph_x_proc_ticket_reply(ac, &th->session_key,
523                                                buf + sizeof(*head), end);
524                 break;
525
526         default:
527                 return -EINVAL;
528         }
529         if (ret)
530                 return ret;
531         if (ac->want_keys == xi->have_keys)
532                 return 0;
533         return -EAGAIN;
534 }
535
536 static int ceph_x_create_authorizer(
537         struct ceph_auth_client *ac, int peer_type,
538         struct ceph_auth_handshake *auth)
539 {
540         struct ceph_x_authorizer *au;
541         struct ceph_x_ticket_handler *th;
542         int ret;
543
544         th = get_ticket_handler(ac, peer_type);
545         if (IS_ERR(th))
546                 return PTR_ERR(th);
547
548         au = kzalloc(sizeof(*au), GFP_NOFS);
549         if (!au)
550                 return -ENOMEM;
551
552         ret = ceph_x_build_authorizer(ac, th, au);
553         if (ret) {
554                 kfree(au);
555                 return ret;
556         }
557
558         auth->authorizer = (struct ceph_authorizer *) au;
559         auth->authorizer_buf = au->buf->vec.iov_base;
560         auth->authorizer_buf_len = au->buf->vec.iov_len;
561         auth->authorizer_reply_buf = au->reply_buf;
562         auth->authorizer_reply_buf_len = sizeof (au->reply_buf);
563
564         return 0;
565 }
566
567 static int ceph_x_update_authorizer(
568         struct ceph_auth_client *ac, int peer_type,
569         struct ceph_auth_handshake *auth)
570 {
571         struct ceph_x_authorizer *au;
572         struct ceph_x_ticket_handler *th;
573
574         th = get_ticket_handler(ac, peer_type);
575         if (IS_ERR(th))
576                 return PTR_ERR(th);
577
578         au = (struct ceph_x_authorizer *)auth->authorizer;
579         if (au->secret_id < th->secret_id) {
580                 dout("ceph_x_update_authorizer service %u secret %llu < %llu\n",
581                      au->service, au->secret_id, th->secret_id);
582                 return ceph_x_build_authorizer(ac, th, au);
583         }
584         return 0;
585 }
586
587 static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac,
588                                           struct ceph_authorizer *a, size_t len)
589 {
590         struct ceph_x_authorizer *au = (void *)a;
591         struct ceph_x_ticket_handler *th;
592         int ret = 0;
593         struct ceph_x_authorize_reply reply;
594         void *preply = &reply;
595         void *p = au->reply_buf;
596         void *end = p + sizeof(au->reply_buf);
597
598         th = get_ticket_handler(ac, au->service);
599         if (IS_ERR(th))
600                 return PTR_ERR(th);
601         ret = ceph_x_decrypt(&th->session_key, &p, end, &preply, sizeof(reply));
602         if (ret < 0)
603                 return ret;
604         if (ret != sizeof(reply))
605                 return -EPERM;
606
607         if (au->nonce + 1 != le64_to_cpu(reply.nonce_plus_one))
608                 ret = -EPERM;
609         else
610                 ret = 0;
611         dout("verify_authorizer_reply nonce %llx got %llx ret %d\n",
612              au->nonce, le64_to_cpu(reply.nonce_plus_one), ret);
613         return ret;
614 }
615
616 static void ceph_x_destroy_authorizer(struct ceph_auth_client *ac,
617                                       struct ceph_authorizer *a)
618 {
619         struct ceph_x_authorizer *au = (void *)a;
620
621         ceph_buffer_put(au->buf);
622         kfree(au);
623 }
624
625
626 static void ceph_x_reset(struct ceph_auth_client *ac)
627 {
628         struct ceph_x_info *xi = ac->private;
629
630         dout("reset\n");
631         xi->starting = true;
632         xi->server_challenge = 0;
633 }
634
635 static void ceph_x_destroy(struct ceph_auth_client *ac)
636 {
637         struct ceph_x_info *xi = ac->private;
638         struct rb_node *p;
639
640         dout("ceph_x_destroy %p\n", ac);
641         ceph_crypto_key_destroy(&xi->secret);
642
643         while ((p = rb_first(&xi->ticket_handlers)) != NULL) {
644                 struct ceph_x_ticket_handler *th =
645                         rb_entry(p, struct ceph_x_ticket_handler, node);
646                 remove_ticket_handler(ac, th);
647         }
648
649         if (xi->auth_authorizer.buf)
650                 ceph_buffer_put(xi->auth_authorizer.buf);
651
652         kfree(ac->private);
653         ac->private = NULL;
654 }
655
656 static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac,
657                                    int peer_type)
658 {
659         struct ceph_x_ticket_handler *th;
660
661         th = get_ticket_handler(ac, peer_type);
662         if (!IS_ERR(th))
663                 memset(&th->validity, 0, sizeof(th->validity));
664 }
665
666
667 static const struct ceph_auth_client_ops ceph_x_ops = {
668         .name = "x",
669         .is_authenticated = ceph_x_is_authenticated,
670         .should_authenticate = ceph_x_should_authenticate,
671         .build_request = ceph_x_build_request,
672         .handle_reply = ceph_x_handle_reply,
673         .create_authorizer = ceph_x_create_authorizer,
674         .update_authorizer = ceph_x_update_authorizer,
675         .verify_authorizer_reply = ceph_x_verify_authorizer_reply,
676         .destroy_authorizer = ceph_x_destroy_authorizer,
677         .invalidate_authorizer = ceph_x_invalidate_authorizer,
678         .reset =  ceph_x_reset,
679         .destroy = ceph_x_destroy,
680 };
681
682
683 int ceph_x_init(struct ceph_auth_client *ac)
684 {
685         struct ceph_x_info *xi;
686         int ret;
687
688         dout("ceph_x_init %p\n", ac);
689         ret = -ENOMEM;
690         xi = kzalloc(sizeof(*xi), GFP_NOFS);
691         if (!xi)
692                 goto out;
693
694         ret = -EINVAL;
695         if (!ac->key) {
696                 pr_err("no secret set (for auth_x protocol)\n");
697                 goto out_nomem;
698         }
699
700         ret = ceph_crypto_key_clone(&xi->secret, ac->key);
701         if (ret < 0) {
702                 pr_err("cannot clone key: %d\n", ret);
703                 goto out_nomem;
704         }
705
706         xi->starting = true;
707         xi->ticket_handlers = RB_ROOT;
708
709         ac->protocol = CEPH_AUTH_CEPHX;
710         ac->private = xi;
711         ac->ops = &ceph_x_ops;
712         return 0;
713
714 out_nomem:
715         kfree(xi);
716 out:
717         return ret;
718 }
719
720