Merge branch 'sched/urgent' into sched/core to pick up fixes
[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 #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_buflen(int ilen)
43 {
44         return sizeof(struct ceph_x_encrypt_header) + ilen + 16 +
45                 sizeof(u32);
46 }
47
48 static int ceph_x_encrypt(struct ceph_crypto_key *secret,
49                           void *ibuf, int ilen, void *obuf, size_t olen)
50 {
51         struct ceph_x_encrypt_header head = {
52                 .struct_v = 1,
53                 .magic = cpu_to_le64(CEPHX_ENC_MAGIC)
54         };
55         size_t len = olen - sizeof(u32);
56         int ret;
57
58         ret = ceph_encrypt2(secret, obuf + sizeof(u32), &len,
59                             &head, sizeof(head), ibuf, ilen);
60         if (ret)
61                 return ret;
62         ceph_encode_32(&obuf, len);
63         return len + sizeof(u32);
64 }
65
66 static int ceph_x_decrypt(struct ceph_crypto_key *secret,
67                           void **p, void *end, void **obuf, size_t olen)
68 {
69         struct ceph_x_encrypt_header head;
70         size_t head_len = sizeof(head);
71         int len, ret;
72
73         len = ceph_decode_32(p);
74         if (*p + len > end)
75                 return -EINVAL;
76
77         dout("ceph_x_decrypt len %d\n", len);
78         if (*obuf == NULL) {
79                 *obuf = kmalloc(len, GFP_NOFS);
80                 if (!*obuf)
81                         return -ENOMEM;
82                 olen = len;
83         }
84
85         ret = ceph_decrypt2(secret, &head, &head_len, *obuf, &olen, *p, len);
86         if (ret)
87                 return ret;
88         if (head.struct_v != 1 || le64_to_cpu(head.magic) != CEPHX_ENC_MAGIC)
89                 return -EPERM;
90         *p += len;
91         return olen;
92 }
93
94 /*
95  * get existing (or insert new) ticket handler
96  */
97 static struct ceph_x_ticket_handler *
98 get_ticket_handler(struct ceph_auth_client *ac, int service)
99 {
100         struct ceph_x_ticket_handler *th;
101         struct ceph_x_info *xi = ac->private;
102         struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node;
103
104         while (*p) {
105                 parent = *p;
106                 th = rb_entry(parent, struct ceph_x_ticket_handler, node);
107                 if (service < th->service)
108                         p = &(*p)->rb_left;
109                 else if (service > th->service)
110                         p = &(*p)->rb_right;
111                 else
112                         return th;
113         }
114
115         /* add it */
116         th = kzalloc(sizeof(*th), GFP_NOFS);
117         if (!th)
118                 return ERR_PTR(-ENOMEM);
119         th->service = service;
120         rb_link_node(&th->node, parent, p);
121         rb_insert_color(&th->node, &xi->ticket_handlers);
122         return th;
123 }
124
125 static void remove_ticket_handler(struct ceph_auth_client *ac,
126                                   struct ceph_x_ticket_handler *th)
127 {
128         struct ceph_x_info *xi = ac->private;
129
130         dout("remove_ticket_handler %p %d\n", th, th->service);
131         rb_erase(&th->node, &xi->ticket_handlers);
132         ceph_crypto_key_destroy(&th->session_key);
133         if (th->ticket_blob)
134                 ceph_buffer_put(th->ticket_blob);
135         kfree(th);
136 }
137
138 static int process_one_ticket(struct ceph_auth_client *ac,
139                               struct ceph_crypto_key *secret,
140                               void **p, void *end)
141 {
142         struct ceph_x_info *xi = ac->private;
143         int type;
144         u8 tkt_struct_v, blob_struct_v;
145         struct ceph_x_ticket_handler *th;
146         void *dbuf = NULL;
147         void *dp, *dend;
148         int dlen;
149         char is_enc;
150         struct timespec validity;
151         struct ceph_crypto_key old_key;
152         void *ticket_buf = NULL;
153         void *tp, *tpend;
154         void **ptp;
155         struct ceph_crypto_key new_session_key;
156         struct ceph_buffer *new_ticket_blob;
157         unsigned long new_expires, new_renew_after;
158         u64 new_secret_id;
159         int ret;
160
161         ceph_decode_need(p, end, sizeof(u32) + 1, bad);
162
163         type = ceph_decode_32(p);
164         dout(" ticket type %d %s\n", type, ceph_entity_type_name(type));
165
166         tkt_struct_v = ceph_decode_8(p);
167         if (tkt_struct_v != 1)
168                 goto bad;
169
170         th = get_ticket_handler(ac, type);
171         if (IS_ERR(th)) {
172                 ret = PTR_ERR(th);
173                 goto out;
174         }
175
176         /* blob for me */
177         dlen = ceph_x_decrypt(secret, p, end, &dbuf, 0);
178         if (dlen <= 0) {
179                 ret = dlen;
180                 goto out;
181         }
182         dout(" decrypted %d bytes\n", dlen);
183         dp = dbuf;
184         dend = dp + dlen;
185
186         tkt_struct_v = ceph_decode_8(&dp);
187         if (tkt_struct_v != 1)
188                 goto bad;
189
190         memcpy(&old_key, &th->session_key, sizeof(old_key));
191         ret = ceph_crypto_key_decode(&new_session_key, &dp, dend);
192         if (ret)
193                 goto out;
194
195         ceph_decode_timespec(&validity, dp);
196         dp += sizeof(struct ceph_timespec);
197         new_expires = get_seconds() + validity.tv_sec;
198         new_renew_after = new_expires - (validity.tv_sec / 4);
199         dout(" expires=%lu renew_after=%lu\n", new_expires,
200              new_renew_after);
201
202         /* ticket blob for service */
203         ceph_decode_8_safe(p, end, is_enc, bad);
204         if (is_enc) {
205                 /* encrypted */
206                 dout(" encrypted ticket\n");
207                 dlen = ceph_x_decrypt(&old_key, p, end, &ticket_buf, 0);
208                 if (dlen < 0) {
209                         ret = dlen;
210                         goto out;
211                 }
212                 tp = ticket_buf;
213                 ptp = &tp;
214                 tpend = *ptp + dlen;
215         } else {
216                 /* unencrypted */
217                 ptp = p;
218                 tpend = end;
219         }
220         ceph_decode_32_safe(ptp, tpend, dlen, bad);
221         dout(" ticket blob is %d bytes\n", dlen);
222         ceph_decode_need(ptp, tpend, 1 + sizeof(u64), bad);
223         blob_struct_v = ceph_decode_8(ptp);
224         new_secret_id = ceph_decode_64(ptp);
225         ret = ceph_decode_buffer(&new_ticket_blob, ptp, tpend);
226         if (ret)
227                 goto out;
228
229         /* all is well, update our ticket */
230         ceph_crypto_key_destroy(&th->session_key);
231         if (th->ticket_blob)
232                 ceph_buffer_put(th->ticket_blob);
233         th->session_key = new_session_key;
234         th->ticket_blob = new_ticket_blob;
235         th->secret_id = new_secret_id;
236         th->expires = new_expires;
237         th->renew_after = new_renew_after;
238         th->have_key = true;
239         dout(" got ticket service %d (%s) secret_id %lld len %d\n",
240              type, ceph_entity_type_name(type), th->secret_id,
241              (int)th->ticket_blob->vec.iov_len);
242         xi->have_keys |= th->service;
243
244 out:
245         kfree(ticket_buf);
246         kfree(dbuf);
247         return ret;
248
249 bad:
250         ret = -EINVAL;
251         goto out;
252 }
253
254 static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac,
255                                     struct ceph_crypto_key *secret,
256                                     void *buf, void *end)
257 {
258         void *p = buf;
259         u8 reply_struct_v;
260         u32 num;
261         int ret;
262
263         ceph_decode_8_safe(&p, end, reply_struct_v, bad);
264         if (reply_struct_v != 1)
265                 return -EINVAL;
266
267         ceph_decode_32_safe(&p, end, num, bad);
268         dout("%d tickets\n", num);
269
270         while (num--) {
271                 ret = process_one_ticket(ac, secret, &p, end);
272                 if (ret)
273                         return ret;
274         }
275
276         return 0;
277
278 bad:
279         return -EINVAL;
280 }
281
282 static void ceph_x_authorizer_cleanup(struct ceph_x_authorizer *au)
283 {
284         ceph_crypto_key_destroy(&au->session_key);
285         if (au->buf) {
286                 ceph_buffer_put(au->buf);
287                 au->buf = NULL;
288         }
289 }
290
291 static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
292                                    struct ceph_x_ticket_handler *th,
293                                    struct ceph_x_authorizer *au)
294 {
295         int maxlen;
296         struct ceph_x_authorize_a *msg_a;
297         struct ceph_x_authorize_b msg_b;
298         void *p, *end;
299         int ret;
300         int ticket_blob_len =
301                 (th->ticket_blob ? th->ticket_blob->vec.iov_len : 0);
302
303         dout("build_authorizer for %s %p\n",
304              ceph_entity_type_name(th->service), au);
305
306         ceph_crypto_key_destroy(&au->session_key);
307         ret = ceph_crypto_key_clone(&au->session_key, &th->session_key);
308         if (ret)
309                 goto out_au;
310
311         maxlen = sizeof(*msg_a) + sizeof(msg_b) +
312                 ceph_x_encrypt_buflen(ticket_blob_len);
313         dout("  need len %d\n", maxlen);
314         if (au->buf && au->buf->alloc_len < maxlen) {
315                 ceph_buffer_put(au->buf);
316                 au->buf = NULL;
317         }
318         if (!au->buf) {
319                 au->buf = ceph_buffer_new(maxlen, GFP_NOFS);
320                 if (!au->buf) {
321                         ret = -ENOMEM;
322                         goto out_au;
323                 }
324         }
325         au->service = th->service;
326         au->secret_id = th->secret_id;
327
328         msg_a = au->buf->vec.iov_base;
329         msg_a->struct_v = 1;
330         msg_a->global_id = cpu_to_le64(ac->global_id);
331         msg_a->service_id = cpu_to_le32(th->service);
332         msg_a->ticket_blob.struct_v = 1;
333         msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id);
334         msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len);
335         if (ticket_blob_len) {
336                 memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base,
337                        th->ticket_blob->vec.iov_len);
338         }
339         dout(" th %p secret_id %lld %lld\n", th, th->secret_id,
340              le64_to_cpu(msg_a->ticket_blob.secret_id));
341
342         p = msg_a + 1;
343         p += ticket_blob_len;
344         end = au->buf->vec.iov_base + au->buf->vec.iov_len;
345
346         get_random_bytes(&au->nonce, sizeof(au->nonce));
347         msg_b.struct_v = 1;
348         msg_b.nonce = cpu_to_le64(au->nonce);
349         ret = ceph_x_encrypt(&au->session_key, &msg_b, sizeof(msg_b),
350                              p, end - p);
351         if (ret < 0)
352                 goto out_au;
353         p += ret;
354         au->buf->vec.iov_len = p - au->buf->vec.iov_base;
355         dout(" built authorizer nonce %llx len %d\n", au->nonce,
356              (int)au->buf->vec.iov_len);
357         BUG_ON(au->buf->vec.iov_len > maxlen);
358         return 0;
359
360 out_au:
361         ceph_x_authorizer_cleanup(au);
362         return ret;
363 }
364
365 static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th,
366                                 void **p, void *end)
367 {
368         ceph_decode_need(p, end, 1 + sizeof(u64), bad);
369         ceph_encode_8(p, 1);
370         ceph_encode_64(p, th->secret_id);
371         if (th->ticket_blob) {
372                 const char *buf = th->ticket_blob->vec.iov_base;
373                 u32 len = th->ticket_blob->vec.iov_len;
374
375                 ceph_encode_32_safe(p, end, len, bad);
376                 ceph_encode_copy_safe(p, end, buf, len, bad);
377         } else {
378                 ceph_encode_32_safe(p, end, 0, bad);
379         }
380
381         return 0;
382 bad:
383         return -ERANGE;
384 }
385
386 static bool need_key(struct ceph_x_ticket_handler *th)
387 {
388         if (!th->have_key)
389                 return true;
390
391         return get_seconds() >= th->renew_after;
392 }
393
394 static bool have_key(struct ceph_x_ticket_handler *th)
395 {
396         if (th->have_key) {
397                 if (get_seconds() >= th->expires)
398                         th->have_key = false;
399         }
400
401         return th->have_key;
402 }
403
404 static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed)
405 {
406         int want = ac->want_keys;
407         struct ceph_x_info *xi = ac->private;
408         int service;
409
410         *pneed = ac->want_keys & ~(xi->have_keys);
411
412         for (service = 1; service <= want; service <<= 1) {
413                 struct ceph_x_ticket_handler *th;
414
415                 if (!(ac->want_keys & service))
416                         continue;
417
418                 if (*pneed & service)
419                         continue;
420
421                 th = get_ticket_handler(ac, service);
422                 if (IS_ERR(th)) {
423                         *pneed |= service;
424                         continue;
425                 }
426
427                 if (need_key(th))
428                         *pneed |= service;
429                 if (!have_key(th))
430                         xi->have_keys &= ~service;
431         }
432 }
433
434 static int ceph_x_build_request(struct ceph_auth_client *ac,
435                                 void *buf, void *end)
436 {
437         struct ceph_x_info *xi = ac->private;
438         int need;
439         struct ceph_x_request_header *head = buf;
440         int ret;
441         struct ceph_x_ticket_handler *th =
442                 get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
443
444         if (IS_ERR(th))
445                 return PTR_ERR(th);
446
447         ceph_x_validate_tickets(ac, &need);
448
449         dout("build_request want %x have %x need %x\n",
450              ac->want_keys, xi->have_keys, need);
451
452         if (need & CEPH_ENTITY_TYPE_AUTH) {
453                 struct ceph_x_authenticate *auth = (void *)(head + 1);
454                 void *p = auth + 1;
455                 struct ceph_x_challenge_blob tmp;
456                 char tmp_enc[40];
457                 u64 *u;
458
459                 if (p > end)
460                         return -ERANGE;
461
462                 dout(" get_auth_session_key\n");
463                 head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY);
464
465                 /* encrypt and hash */
466                 get_random_bytes(&auth->client_challenge, sizeof(u64));
467                 tmp.client_challenge = auth->client_challenge;
468                 tmp.server_challenge = cpu_to_le64(xi->server_challenge);
469                 ret = ceph_x_encrypt(&xi->secret, &tmp, sizeof(tmp),
470                                      tmp_enc, sizeof(tmp_enc));
471                 if (ret < 0)
472                         return ret;
473
474                 auth->struct_v = 1;
475                 auth->key = 0;
476                 for (u = (u64 *)tmp_enc; u + 1 <= (u64 *)(tmp_enc + ret); u++)
477                         auth->key ^= *(__le64 *)u;
478                 dout(" server_challenge %llx client_challenge %llx key %llx\n",
479                      xi->server_challenge, le64_to_cpu(auth->client_challenge),
480                      le64_to_cpu(auth->key));
481
482                 /* now encode the old ticket if exists */
483                 ret = ceph_x_encode_ticket(th, &p, end);
484                 if (ret < 0)
485                         return ret;
486
487                 return p - buf;
488         }
489
490         if (need) {
491                 void *p = head + 1;
492                 struct ceph_x_service_ticket_request *req;
493
494                 if (p > end)
495                         return -ERANGE;
496                 head->op = cpu_to_le16(CEPHX_GET_PRINCIPAL_SESSION_KEY);
497
498                 ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer);
499                 if (ret)
500                         return ret;
501                 ceph_encode_copy(&p, xi->auth_authorizer.buf->vec.iov_base,
502                                  xi->auth_authorizer.buf->vec.iov_len);
503
504                 req = p;
505                 req->keys = cpu_to_le32(need);
506                 p += sizeof(*req);
507                 return p - buf;
508         }
509
510         return 0;
511 }
512
513 static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result,
514                                void *buf, void *end)
515 {
516         struct ceph_x_info *xi = ac->private;
517         struct ceph_x_reply_header *head = buf;
518         struct ceph_x_ticket_handler *th;
519         int len = end - buf;
520         int op;
521         int ret;
522
523         if (result)
524                 return result;  /* XXX hmm? */
525
526         if (xi->starting) {
527                 /* it's a hello */
528                 struct ceph_x_server_challenge *sc = buf;
529
530                 if (len != sizeof(*sc))
531                         return -EINVAL;
532                 xi->server_challenge = le64_to_cpu(sc->server_challenge);
533                 dout("handle_reply got server challenge %llx\n",
534                      xi->server_challenge);
535                 xi->starting = false;
536                 xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH;
537                 return -EAGAIN;
538         }
539
540         op = le16_to_cpu(head->op);
541         result = le32_to_cpu(head->result);
542         dout("handle_reply op %d result %d\n", op, result);
543         switch (op) {
544         case CEPHX_GET_AUTH_SESSION_KEY:
545                 /* verify auth key */
546                 ret = ceph_x_proc_ticket_reply(ac, &xi->secret,
547                                                buf + sizeof(*head), end);
548                 break;
549
550         case CEPHX_GET_PRINCIPAL_SESSION_KEY:
551                 th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
552                 if (IS_ERR(th))
553                         return PTR_ERR(th);
554                 ret = ceph_x_proc_ticket_reply(ac, &th->session_key,
555                                                buf + sizeof(*head), end);
556                 break;
557
558         default:
559                 return -EINVAL;
560         }
561         if (ret)
562                 return ret;
563         if (ac->want_keys == xi->have_keys)
564                 return 0;
565         return -EAGAIN;
566 }
567
568 static void ceph_x_destroy_authorizer(struct ceph_authorizer *a)
569 {
570         struct ceph_x_authorizer *au = (void *)a;
571
572         ceph_x_authorizer_cleanup(au);
573         kfree(au);
574 }
575
576 static int ceph_x_create_authorizer(
577         struct ceph_auth_client *ac, int peer_type,
578         struct ceph_auth_handshake *auth)
579 {
580         struct ceph_x_authorizer *au;
581         struct ceph_x_ticket_handler *th;
582         int ret;
583
584         th = get_ticket_handler(ac, peer_type);
585         if (IS_ERR(th))
586                 return PTR_ERR(th);
587
588         au = kzalloc(sizeof(*au), GFP_NOFS);
589         if (!au)
590                 return -ENOMEM;
591
592         au->base.destroy = ceph_x_destroy_authorizer;
593
594         ret = ceph_x_build_authorizer(ac, th, au);
595         if (ret) {
596                 kfree(au);
597                 return ret;
598         }
599
600         auth->authorizer = (struct ceph_authorizer *) au;
601         auth->authorizer_buf = au->buf->vec.iov_base;
602         auth->authorizer_buf_len = au->buf->vec.iov_len;
603         auth->authorizer_reply_buf = au->reply_buf;
604         auth->authorizer_reply_buf_len = sizeof (au->reply_buf);
605         auth->sign_message = ac->ops->sign_message;
606         auth->check_message_signature = ac->ops->check_message_signature;
607
608         return 0;
609 }
610
611 static int ceph_x_update_authorizer(
612         struct ceph_auth_client *ac, int peer_type,
613         struct ceph_auth_handshake *auth)
614 {
615         struct ceph_x_authorizer *au;
616         struct ceph_x_ticket_handler *th;
617
618         th = get_ticket_handler(ac, peer_type);
619         if (IS_ERR(th))
620                 return PTR_ERR(th);
621
622         au = (struct ceph_x_authorizer *)auth->authorizer;
623         if (au->secret_id < th->secret_id) {
624                 dout("ceph_x_update_authorizer service %u secret %llu < %llu\n",
625                      au->service, au->secret_id, th->secret_id);
626                 return ceph_x_build_authorizer(ac, th, au);
627         }
628         return 0;
629 }
630
631 static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac,
632                                           struct ceph_authorizer *a, size_t len)
633 {
634         struct ceph_x_authorizer *au = (void *)a;
635         int ret = 0;
636         struct ceph_x_authorize_reply reply;
637         void *preply = &reply;
638         void *p = au->reply_buf;
639         void *end = p + sizeof(au->reply_buf);
640
641         ret = ceph_x_decrypt(&au->session_key, &p, end, &preply, sizeof(reply));
642         if (ret < 0)
643                 return ret;
644         if (ret != sizeof(reply))
645                 return -EPERM;
646
647         if (au->nonce + 1 != le64_to_cpu(reply.nonce_plus_one))
648                 ret = -EPERM;
649         else
650                 ret = 0;
651         dout("verify_authorizer_reply nonce %llx got %llx ret %d\n",
652              au->nonce, le64_to_cpu(reply.nonce_plus_one), ret);
653         return ret;
654 }
655
656 static void ceph_x_reset(struct ceph_auth_client *ac)
657 {
658         struct ceph_x_info *xi = ac->private;
659
660         dout("reset\n");
661         xi->starting = true;
662         xi->server_challenge = 0;
663 }
664
665 static void ceph_x_destroy(struct ceph_auth_client *ac)
666 {
667         struct ceph_x_info *xi = ac->private;
668         struct rb_node *p;
669
670         dout("ceph_x_destroy %p\n", ac);
671         ceph_crypto_key_destroy(&xi->secret);
672
673         while ((p = rb_first(&xi->ticket_handlers)) != NULL) {
674                 struct ceph_x_ticket_handler *th =
675                         rb_entry(p, struct ceph_x_ticket_handler, node);
676                 remove_ticket_handler(ac, th);
677         }
678
679         ceph_x_authorizer_cleanup(&xi->auth_authorizer);
680
681         kfree(ac->private);
682         ac->private = NULL;
683 }
684
685 static void invalidate_ticket(struct ceph_auth_client *ac, int peer_type)
686 {
687         struct ceph_x_ticket_handler *th;
688
689         th = get_ticket_handler(ac, peer_type);
690         if (!IS_ERR(th))
691                 th->have_key = false;
692 }
693
694 static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac,
695                                          int peer_type)
696 {
697         /*
698          * We are to invalidate a service ticket in the hopes of
699          * getting a new, hopefully more valid, one.  But, we won't get
700          * it unless our AUTH ticket is good, so invalidate AUTH ticket
701          * as well, just in case.
702          */
703         invalidate_ticket(ac, peer_type);
704         invalidate_ticket(ac, CEPH_ENTITY_TYPE_AUTH);
705 }
706
707 static int calcu_signature(struct ceph_x_authorizer *au,
708                            struct ceph_msg *msg, __le64 *sig)
709 {
710         int ret;
711         char tmp_enc[40];
712         __le32 tmp[5] = {
713                 cpu_to_le32(16), msg->hdr.crc, msg->footer.front_crc,
714                 msg->footer.middle_crc, msg->footer.data_crc,
715         };
716         ret = ceph_x_encrypt(&au->session_key, &tmp, sizeof(tmp),
717                              tmp_enc, sizeof(tmp_enc));
718         if (ret < 0)
719                 return ret;
720         *sig = *(__le64*)(tmp_enc + 4);
721         return 0;
722 }
723
724 static int ceph_x_sign_message(struct ceph_auth_handshake *auth,
725                                struct ceph_msg *msg)
726 {
727         int ret;
728
729         if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
730                 return 0;
731
732         ret = calcu_signature((struct ceph_x_authorizer *)auth->authorizer,
733                               msg, &msg->footer.sig);
734         if (ret < 0)
735                 return ret;
736         msg->footer.flags |= CEPH_MSG_FOOTER_SIGNED;
737         return 0;
738 }
739
740 static int ceph_x_check_message_signature(struct ceph_auth_handshake *auth,
741                                           struct ceph_msg *msg)
742 {
743         __le64 sig_check;
744         int ret;
745
746         if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
747                 return 0;
748
749         ret = calcu_signature((struct ceph_x_authorizer *)auth->authorizer,
750                               msg, &sig_check);
751         if (ret < 0)
752                 return ret;
753         if (sig_check == msg->footer.sig)
754                 return 0;
755         if (msg->footer.flags & CEPH_MSG_FOOTER_SIGNED)
756                 dout("ceph_x_check_message_signature %p has signature %llx "
757                      "expect %llx\n", msg, msg->footer.sig, sig_check);
758         else
759                 dout("ceph_x_check_message_signature %p sender did not set "
760                      "CEPH_MSG_FOOTER_SIGNED\n", msg);
761         return -EBADMSG;
762 }
763
764 static const struct ceph_auth_client_ops ceph_x_ops = {
765         .name = "x",
766         .is_authenticated = ceph_x_is_authenticated,
767         .should_authenticate = ceph_x_should_authenticate,
768         .build_request = ceph_x_build_request,
769         .handle_reply = ceph_x_handle_reply,
770         .create_authorizer = ceph_x_create_authorizer,
771         .update_authorizer = ceph_x_update_authorizer,
772         .verify_authorizer_reply = ceph_x_verify_authorizer_reply,
773         .invalidate_authorizer = ceph_x_invalidate_authorizer,
774         .reset =  ceph_x_reset,
775         .destroy = ceph_x_destroy,
776         .sign_message = ceph_x_sign_message,
777         .check_message_signature = ceph_x_check_message_signature,
778 };
779
780
781 int ceph_x_init(struct ceph_auth_client *ac)
782 {
783         struct ceph_x_info *xi;
784         int ret;
785
786         dout("ceph_x_init %p\n", ac);
787         ret = -ENOMEM;
788         xi = kzalloc(sizeof(*xi), GFP_NOFS);
789         if (!xi)
790                 goto out;
791
792         ret = -EINVAL;
793         if (!ac->key) {
794                 pr_err("no secret set (for auth_x protocol)\n");
795                 goto out_nomem;
796         }
797
798         ret = ceph_crypto_key_clone(&xi->secret, ac->key);
799         if (ret < 0) {
800                 pr_err("cannot clone key: %d\n", ret);
801                 goto out_nomem;
802         }
803
804         xi->starting = true;
805         xi->ticket_handlers = RB_ROOT;
806
807         ac->protocol = CEPH_AUTH_CEPHX;
808         ac->private = xi;
809         ac->ops = &ceph_x_ops;
810         return 0;
811
812 out_nomem:
813         kfree(xi);
814 out:
815         return ret;
816 }
817
818