blob: f0318427b6dabd0a3d009288f1e29ba892c6ca84 [file] [log] [blame]
Sage Weilec0994e2010-02-02 16:25:35 -08001
2#include "ceph_debug.h"
3
4#include <linux/err.h>
5#include <linux/module.h>
6#include <linux/random.h>
7
8#include "auth_x.h"
9#include "auth_x_protocol.h"
10#include "crypto.h"
11#include "auth.h"
12#include "decode.h"
13
14struct kmem_cache *ceph_x_ticketbuf_cachep;
15
16#define TEMP_TICKET_BUF_LEN 256
17
18static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed);
19
20static 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
31static int ceph_x_encrypt(struct ceph_crypto_key *secret,
32 void *ibuf, int ilen, void *obuf, size_t olen)
33{
34 struct ceph_x_encrypt_header head = {
35 .struct_v = 1,
36 .magic = cpu_to_le64(CEPHX_ENC_MAGIC)
37 };
38 size_t len = olen - sizeof(u32);
39 int ret;
40
41 ret = ceph_encrypt2(secret, obuf + sizeof(u32), &len,
42 &head, sizeof(head), ibuf, ilen);
43 if (ret)
44 return ret;
45 ceph_encode_32(&obuf, len);
46 return len + sizeof(u32);
47}
48
49static int ceph_x_decrypt(struct ceph_crypto_key *secret,
50 void **p, void *end, void *obuf, size_t olen)
51{
52 struct ceph_x_encrypt_header head;
53 size_t head_len = sizeof(head);
54 int len, ret;
55
56 len = ceph_decode_32(p);
57 if (*p + len > end)
58 return -EINVAL;
59
60 dout("ceph_x_decrypt len %d\n", len);
61 ret = ceph_decrypt2(secret, &head, &head_len, obuf, &olen,
62 *p, len);
63 if (ret)
64 return ret;
65 if (head.struct_v != 1 || le64_to_cpu(head.magic) != CEPHX_ENC_MAGIC)
66 return -EPERM;
67 *p += len;
68 return olen;
69}
70
71/*
72 * get existing (or insert new) ticket handler
73 */
74struct ceph_x_ticket_handler *get_ticket_handler(struct ceph_auth_client *ac,
75 int service)
76{
77 struct ceph_x_ticket_handler *th;
78 struct ceph_x_info *xi = ac->private;
79 struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node;
80
81 while (*p) {
82 parent = *p;
83 th = rb_entry(parent, struct ceph_x_ticket_handler, node);
84 if (service < th->service)
85 p = &(*p)->rb_left;
86 else if (service > th->service)
87 p = &(*p)->rb_right;
88 else
89 return th;
90 }
91
92 /* add it */
93 th = kzalloc(sizeof(*th), GFP_NOFS);
94 if (!th)
95 return ERR_PTR(-ENOMEM);
96 th->service = service;
97 rb_link_node(&th->node, parent, p);
98 rb_insert_color(&th->node, &xi->ticket_handlers);
99 return th;
100}
101
102static void remove_ticket_handler(struct ceph_auth_client *ac,
103 struct ceph_x_ticket_handler *th)
104{
105 struct ceph_x_info *xi = ac->private;
106
107 dout("remove_ticket_handler %p %d\n", th, th->service);
108 rb_erase(&th->node, &xi->ticket_handlers);
109 ceph_crypto_key_destroy(&th->session_key);
110 if (th->ticket_blob)
111 ceph_buffer_put(th->ticket_blob);
112 kfree(th);
113}
114
115static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac,
116 struct ceph_crypto_key *secret,
117 void *buf, void *end)
118{
119 struct ceph_x_info *xi = ac->private;
120 int num;
121 void *p = buf;
122 int ret;
123 char *dbuf;
124 char *ticket_buf;
125 u8 struct_v;
126
127 dbuf = kmem_cache_alloc(ceph_x_ticketbuf_cachep, GFP_NOFS | GFP_ATOMIC);
128 if (!dbuf)
129 return -ENOMEM;
130
131 ret = -ENOMEM;
132 ticket_buf = kmem_cache_alloc(ceph_x_ticketbuf_cachep,
133 GFP_NOFS | GFP_ATOMIC);
134 if (!ticket_buf)
135 goto out_dbuf;
136
137 ceph_decode_need(&p, end, 1 + sizeof(u32), bad);
138 struct_v = ceph_decode_8(&p);
139 if (struct_v != 1)
140 goto bad;
141 num = ceph_decode_32(&p);
142 dout("%d tickets\n", num);
143 while (num--) {
144 int type;
145 u8 struct_v;
146 struct ceph_x_ticket_handler *th;
147 void *dp, *dend;
148 int dlen;
149 char is_enc;
150 struct timespec validity;
151 struct ceph_crypto_key old_key;
152 void *tp, *tpend;
153
154 ceph_decode_need(&p, end, sizeof(u32) + 1, bad);
155
156 type = ceph_decode_32(&p);
157 dout(" ticket type %d %s\n", type, ceph_entity_type_name(type));
158
159 struct_v = ceph_decode_8(&p);
160 if (struct_v != 1)
161 goto bad;
162
163 th = get_ticket_handler(ac, type);
164 if (IS_ERR(th)) {
165 ret = PTR_ERR(th);
166 goto out;
167 }
168
169 /* blob for me */
170 dlen = ceph_x_decrypt(secret, &p, end, dbuf,
171 TEMP_TICKET_BUF_LEN);
172 if (dlen <= 0) {
173 ret = dlen;
174 goto out;
175 }
176 dout(" decrypted %d bytes\n", dlen);
177 dend = dbuf + dlen;
178 dp = dbuf;
179
180 struct_v = ceph_decode_8(&dp);
181 if (struct_v != 1)
182 goto bad;
183
184 memcpy(&old_key, &th->session_key, sizeof(old_key));
185 ret = ceph_crypto_key_decode(&th->session_key, &dp, dend);
186 if (ret)
187 goto out;
188
189 ceph_decode_copy(&dp, &th->validity, sizeof(th->validity));
190 ceph_decode_timespec(&validity, &th->validity);
191 th->expires = get_seconds() + validity.tv_sec;
192 th->renew_after = th->expires - (validity.tv_sec / 4);
193 dout(" expires=%lu renew_after=%lu\n", th->expires,
194 th->renew_after);
195
196 /* ticket blob for service */
197 ceph_decode_8_safe(&p, end, is_enc, bad);
198 tp = ticket_buf;
199 if (is_enc) {
200 /* encrypted */
201 dout(" encrypted ticket\n");
202 dlen = ceph_x_decrypt(&old_key, &p, end, ticket_buf,
203 TEMP_TICKET_BUF_LEN);
204 if (dlen < 0) {
205 ret = dlen;
206 goto out;
207 }
208 dlen = ceph_decode_32(&tp);
209 } else {
210 /* unencrypted */
211 ceph_decode_32_safe(&p, end, dlen, bad);
212 ceph_decode_need(&p, end, dlen, bad);
213 ceph_decode_copy(&p, ticket_buf, dlen);
214 }
215 tpend = tp + dlen;
216 dout(" ticket blob is %d bytes\n", dlen);
217 ceph_decode_need(&tp, tpend, 1 + sizeof(u64), bad);
218 struct_v = ceph_decode_8(&tp);
219 th->secret_id = ceph_decode_64(&tp);
220 ret = ceph_decode_buffer(&th->ticket_blob, &tp, tpend);
221 if (ret)
222 goto out;
223 dout(" got ticket service %d (%s) secret_id %lld len %d\n",
224 type, ceph_entity_type_name(type), th->secret_id,
225 (int)th->ticket_blob->vec.iov_len);
226 xi->have_keys |= th->service;
227 }
228
229 ret = 0;
230out:
231 kmem_cache_free(ceph_x_ticketbuf_cachep, ticket_buf);
232out_dbuf:
233 kmem_cache_free(ceph_x_ticketbuf_cachep, dbuf);
234 return ret;
235
236bad:
237 ret = -EINVAL;
238 goto out;
239}
240
241static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
242 struct ceph_x_ticket_handler *th,
243 struct ceph_x_authorizer *au)
244{
245 int len;
246 struct ceph_x_authorize_a *msg_a;
247 struct ceph_x_authorize_b msg_b;
248 void *p, *end;
249 int ret;
250 int ticket_blob_len =
251 (th->ticket_blob ? th->ticket_blob->vec.iov_len : 0);
252
253 dout("build_authorizer for %s %p\n",
254 ceph_entity_type_name(th->service), au);
255
256 len = sizeof(*msg_a) + sizeof(msg_b) + sizeof(u32) +
257 ticket_blob_len + 16;
258 dout(" need len %d\n", len);
259 if (au->buf && au->buf->alloc_len < len) {
260 ceph_buffer_put(au->buf);
261 au->buf = NULL;
262 }
263 if (!au->buf) {
264 au->buf = ceph_buffer_new(len, GFP_NOFS);
265 if (!au->buf)
266 return -ENOMEM;
267 }
268 au->service = th->service;
269
270 msg_a = au->buf->vec.iov_base;
271 msg_a->struct_v = 1;
272 msg_a->global_id = cpu_to_le64(ac->global_id);
273 msg_a->service_id = cpu_to_le32(th->service);
274 msg_a->ticket_blob.struct_v = 1;
275 msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id);
276 msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len);
277 if (ticket_blob_len) {
278 memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base,
279 th->ticket_blob->vec.iov_len);
280 }
281 dout(" th %p secret_id %lld %lld\n", th, th->secret_id,
282 le64_to_cpu(msg_a->ticket_blob.secret_id));
283
284 p = msg_a + 1;
285 p += ticket_blob_len;
286 end = au->buf->vec.iov_base + au->buf->vec.iov_len;
287
288 get_random_bytes(&au->nonce, sizeof(au->nonce));
289 msg_b.struct_v = 1;
290 msg_b.nonce = cpu_to_le64(au->nonce);
291 ret = ceph_x_encrypt(&th->session_key, &msg_b, sizeof(msg_b),
292 p, end - p);
293 if (ret < 0)
294 goto out_buf;
295 p += ret;
296 au->buf->vec.iov_len = p - au->buf->vec.iov_base;
297 dout(" built authorizer nonce %llx len %d\n", au->nonce,
298 (int)au->buf->vec.iov_len);
299 return 0;
300
301out_buf:
302 ceph_buffer_put(au->buf);
303 au->buf = NULL;
304 return ret;
305}
306
307static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th,
308 void **p, void *end)
309{
310 ceph_decode_need(p, end, 1 + sizeof(u64), bad);
311 ceph_encode_8(p, 1);
312 ceph_encode_64(p, th->secret_id);
313 if (th->ticket_blob) {
314 const char *buf = th->ticket_blob->vec.iov_base;
315 u32 len = th->ticket_blob->vec.iov_len;
316
317 ceph_encode_32_safe(p, end, len, bad);
318 ceph_encode_copy_safe(p, end, buf, len, bad);
319 } else {
320 ceph_encode_32_safe(p, end, 0, bad);
321 }
322
323 return 0;
324bad:
325 return -ERANGE;
326}
327
328static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed)
329{
330 int want = ac->want_keys;
331 struct ceph_x_info *xi = ac->private;
332 int service;
333
334 *pneed = ac->want_keys & ~(xi->have_keys);
335
336 for (service = 1; service <= want; service <<= 1) {
337 struct ceph_x_ticket_handler *th;
338
339 if (!(ac->want_keys & service))
340 continue;
341
342 if (*pneed & service)
343 continue;
344
345 th = get_ticket_handler(ac, service);
346
347 if (!th) {
348 *pneed |= service;
349 continue;
350 }
351
352 if (get_seconds() >= th->renew_after)
353 *pneed |= service;
354 if (get_seconds() >= th->expires)
355 xi->have_keys &= ~service;
356 }
357}
358
359
360static int ceph_x_build_request(struct ceph_auth_client *ac,
361 void *buf, void *end)
362{
363 struct ceph_x_info *xi = ac->private;
364 int need;
365 struct ceph_x_request_header *head = buf;
366 int ret;
367 struct ceph_x_ticket_handler *th =
368 get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
369
370 ceph_x_validate_tickets(ac, &need);
371
372 dout("build_request want %x have %x need %x\n",
373 ac->want_keys, xi->have_keys, need);
374
375 if (need & CEPH_ENTITY_TYPE_AUTH) {
376 struct ceph_x_authenticate *auth = (void *)(head + 1);
377 void *p = auth + 1;
378 struct ceph_x_challenge_blob tmp;
379 char tmp_enc[40];
380 u64 *u;
381
382 if (p > end)
383 return -ERANGE;
384
385 dout(" get_auth_session_key\n");
386 head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY);
387
388 /* encrypt and hash */
389 get_random_bytes(&auth->client_challenge, sizeof(u64));
390 tmp.client_challenge = auth->client_challenge;
391 tmp.server_challenge = cpu_to_le64(xi->server_challenge);
392 ret = ceph_x_encrypt(&xi->secret, &tmp, sizeof(tmp),
393 tmp_enc, sizeof(tmp_enc));
394 if (ret < 0)
395 return ret;
396
397 auth->struct_v = 1;
398 auth->key = 0;
399 for (u = (u64 *)tmp_enc; u + 1 <= (u64 *)(tmp_enc + ret); u++)
400 auth->key ^= *u;
401 dout(" server_challenge %llx client_challenge %llx key %llx\n",
402 xi->server_challenge, le64_to_cpu(auth->client_challenge),
403 le64_to_cpu(auth->key));
404
405 /* now encode the old ticket if exists */
406 ret = ceph_x_encode_ticket(th, &p, end);
407 if (ret < 0)
408 return ret;
409
410 return p - buf;
411 }
412
413 if (need) {
414 void *p = head + 1;
415 struct ceph_x_service_ticket_request *req;
416
417 if (p > end)
418 return -ERANGE;
419 head->op = cpu_to_le16(CEPHX_GET_PRINCIPAL_SESSION_KEY);
420
421 BUG_ON(!th);
422 ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer);
423 if (ret)
424 return ret;
425 ceph_encode_copy(&p, xi->auth_authorizer.buf->vec.iov_base,
426 xi->auth_authorizer.buf->vec.iov_len);
427
428 req = p;
429 req->keys = cpu_to_le32(need);
430 p += sizeof(*req);
431 return p - buf;
432 }
433
434 return 0;
435}
436
437static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result,
438 void *buf, void *end)
439{
440 struct ceph_x_info *xi = ac->private;
441 struct ceph_x_reply_header *head = buf;
442 struct ceph_x_ticket_handler *th;
443 int len = end - buf;
444 int op;
445 int ret;
446
447 if (result)
448 return result; /* XXX hmm? */
449
450 if (xi->starting) {
451 /* it's a hello */
452 struct ceph_x_server_challenge *sc = buf;
453
454 if (len != sizeof(*sc))
455 return -EINVAL;
456 xi->server_challenge = le64_to_cpu(sc->server_challenge);
457 dout("handle_reply got server challenge %llx\n",
458 xi->server_challenge);
459 xi->starting = false;
460 xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH;
461 return -EAGAIN;
462 }
463
464 op = le32_to_cpu(head->op);
465 result = le32_to_cpu(head->result);
466 dout("handle_reply op %d result %d\n", op, result);
467 switch (op) {
468 case CEPHX_GET_AUTH_SESSION_KEY:
469 /* verify auth key */
470 ret = ceph_x_proc_ticket_reply(ac, &xi->secret,
471 buf + sizeof(*head), end);
472 break;
473
474 case CEPHX_GET_PRINCIPAL_SESSION_KEY:
475 th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
476 BUG_ON(!th);
477 ret = ceph_x_proc_ticket_reply(ac, &th->session_key,
478 buf + sizeof(*head), end);
479 break;
480
481 default:
482 return -EINVAL;
483 }
484 if (ret)
485 return ret;
486 if (ac->want_keys == xi->have_keys)
487 return 0;
488 return -EAGAIN;
489}
490
491static int ceph_x_create_authorizer(
492 struct ceph_auth_client *ac, int peer_type,
493 struct ceph_authorizer **a,
494 void **buf, size_t *len,
495 void **reply_buf, size_t *reply_len)
496{
497 struct ceph_x_authorizer *au;
498 struct ceph_x_ticket_handler *th;
499 int ret;
500
501 th = get_ticket_handler(ac, peer_type);
502 if (IS_ERR(th))
503 return PTR_ERR(th);
504
505 au = kzalloc(sizeof(*au), GFP_NOFS);
506 if (!au)
507 return -ENOMEM;
508
509 ret = ceph_x_build_authorizer(ac, th, au);
510 if (ret) {
511 kfree(au);
512 return ret;
513 }
514
515 *a = (struct ceph_authorizer *)au;
516 *buf = au->buf->vec.iov_base;
517 *len = au->buf->vec.iov_len;
518 *reply_buf = au->reply_buf;
519 *reply_len = sizeof(au->reply_buf);
520 return 0;
521}
522
523static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac,
524 struct ceph_authorizer *a, size_t len)
525{
526 struct ceph_x_authorizer *au = (void *)a;
527 struct ceph_x_ticket_handler *th;
528 int ret = 0;
529 struct ceph_x_authorize_reply reply;
530 void *p = au->reply_buf;
531 void *end = p + sizeof(au->reply_buf);
532
533 th = get_ticket_handler(ac, au->service);
534 if (!th)
535 return -EIO; /* hrm! */
536 ret = ceph_x_decrypt(&th->session_key, &p, end, &reply, sizeof(reply));
537 if (ret < 0)
538 return ret;
539 if (ret != sizeof(reply))
540 return -EPERM;
541
542 if (au->nonce + 1 != le64_to_cpu(reply.nonce_plus_one))
543 ret = -EPERM;
544 else
545 ret = 0;
546 dout("verify_authorizer_reply nonce %llx got %llx ret %d\n",
547 au->nonce, le64_to_cpu(reply.nonce_plus_one), ret);
548 return ret;
549}
550
551static void ceph_x_destroy_authorizer(struct ceph_auth_client *ac,
552 struct ceph_authorizer *a)
553{
554 struct ceph_x_authorizer *au = (void *)a;
555
556 ceph_buffer_put(au->buf);
557 kfree(au);
558}
559
560
561static void ceph_x_reset(struct ceph_auth_client *ac)
562{
563 struct ceph_x_info *xi = ac->private;
564
565 dout("reset\n");
566 xi->starting = true;
567 xi->server_challenge = 0;
568}
569
570static void ceph_x_destroy(struct ceph_auth_client *ac)
571{
572 struct ceph_x_info *xi = ac->private;
573 struct rb_node *p;
574
575 dout("ceph_x_destroy %p\n", ac);
576 ceph_crypto_key_destroy(&xi->secret);
577
578 while ((p = rb_first(&xi->ticket_handlers)) != NULL) {
579 struct ceph_x_ticket_handler *th =
580 rb_entry(p, struct ceph_x_ticket_handler, node);
581 remove_ticket_handler(ac, th);
582 }
583
584 kmem_cache_destroy(ceph_x_ticketbuf_cachep);
585
586 kfree(ac->private);
587 ac->private = NULL;
588}
589
590static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac,
591 int peer_type)
592{
593 struct ceph_x_ticket_handler *th;
594
595 th = get_ticket_handler(ac, peer_type);
596 if (th && !IS_ERR(th))
597 remove_ticket_handler(ac, th);
598}
599
600
601static const struct ceph_auth_client_ops ceph_x_ops = {
602 .is_authenticated = ceph_x_is_authenticated,
603 .build_request = ceph_x_build_request,
604 .handle_reply = ceph_x_handle_reply,
605 .create_authorizer = ceph_x_create_authorizer,
606 .verify_authorizer_reply = ceph_x_verify_authorizer_reply,
607 .destroy_authorizer = ceph_x_destroy_authorizer,
608 .invalidate_authorizer = ceph_x_invalidate_authorizer,
609 .reset = ceph_x_reset,
610 .destroy = ceph_x_destroy,
611};
612
613
614int ceph_x_init(struct ceph_auth_client *ac)
615{
616 struct ceph_x_info *xi;
617 int ret;
618
619 dout("ceph_x_init %p\n", ac);
620 xi = kzalloc(sizeof(*xi), GFP_NOFS);
621 if (!xi)
622 return -ENOMEM;
623
624 ret = -ENOMEM;
625 ceph_x_ticketbuf_cachep = kmem_cache_create("ceph_x_ticketbuf",
626 TEMP_TICKET_BUF_LEN, 8,
627 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
628 NULL);
629 if (!ceph_x_ticketbuf_cachep)
630 goto done_nomem;
631 ret = -EINVAL;
632 if (!ac->secret) {
633 pr_err("no secret set (for auth_x protocol)\n");
634 goto done_nomem;
635 }
636
637 ret = ceph_crypto_key_unarmor(&xi->secret, ac->secret);
638 if (ret)
639 goto done_nomem;
640
641 xi->starting = true;
642 xi->ticket_handlers = RB_ROOT;
643
644 ac->protocol = CEPH_AUTH_CEPHX;
645 ac->private = xi;
646 ac->ops = &ceph_x_ops;
647 return 0;
648
649done_nomem:
650 kfree(xi);
651 if (ceph_x_ticketbuf_cachep)
652 kmem_cache_destroy(ceph_x_ticketbuf_cachep);
653 return ret;
654}
655
656