1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/ceph/ceph_debug.h>
4
5#include <linux/err.h>
6#include <linux/module.h>
7#include <linux/random.h>
8#include <linux/slab.h>
9
10#include <linux/ceph/decode.h>
11#include <linux/ceph/auth.h>
12#include <linux/ceph/ceph_features.h>
13#include <linux/ceph/libceph.h>
14#include <linux/ceph/messenger.h>
15
16#include "crypto.h"
17#include "auth_x.h"
18#include "auth_x_protocol.h"
19
20static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed);
21
22static int ceph_x_is_authenticated(struct ceph_auth_client *ac)
23{
24	struct ceph_x_info *xi = ac->private;
25	int missing;
26	int need;  /* missing + need renewal */
27
28	ceph_x_validate_tickets(ac, &need);
29	missing = ac->want_keys & ~xi->have_keys;
30	WARN_ON((need & missing) != missing);
31	dout("%s want 0x%x have 0x%x missing 0x%x -> %d\n", __func__,
32	     ac->want_keys, xi->have_keys, missing, !missing);
33	return !missing;
34}
35
36static int ceph_x_should_authenticate(struct ceph_auth_client *ac)
37{
38	struct ceph_x_info *xi = ac->private;
39	int need;
40
41	ceph_x_validate_tickets(ac, &need);
42	dout("%s want 0x%x have 0x%x need 0x%x -> %d\n", __func__,
43	     ac->want_keys, xi->have_keys, need, !!need);
44	return !!need;
45}
46
47static int ceph_x_encrypt_offset(void)
48{
49	return sizeof(u32) + sizeof(struct ceph_x_encrypt_header);
50}
51
52static int ceph_x_encrypt_buflen(int ilen)
53{
54	return ceph_x_encrypt_offset() + ilen + 16;
55}
56
57static int ceph_x_encrypt(struct ceph_crypto_key *secret, void *buf,
58			  int buf_len, int plaintext_len)
59{
60	struct ceph_x_encrypt_header *hdr = buf + sizeof(u32);
61	int ciphertext_len;
62	int ret;
63
64	hdr->struct_v = 1;
65	hdr->magic = cpu_to_le64(CEPHX_ENC_MAGIC);
66
67	ret = ceph_crypt(secret, true, buf + sizeof(u32), buf_len - sizeof(u32),
68			 plaintext_len + sizeof(struct ceph_x_encrypt_header),
69			 &ciphertext_len);
70	if (ret)
71		return ret;
72
73	ceph_encode_32(&buf, ciphertext_len);
74	return sizeof(u32) + ciphertext_len;
75}
76
77static int __ceph_x_decrypt(struct ceph_crypto_key *secret, void *p,
78			    int ciphertext_len)
79{
80	struct ceph_x_encrypt_header *hdr = p;
81	int plaintext_len;
82	int ret;
83
84	ret = ceph_crypt(secret, false, p, ciphertext_len, ciphertext_len,
85			 &plaintext_len);
86	if (ret)
87		return ret;
88
89	if (le64_to_cpu(hdr->magic) != CEPHX_ENC_MAGIC) {
90		pr_err("%s bad magic\n", __func__);
91		return -EINVAL;
92	}
93
94	return plaintext_len - sizeof(*hdr);
95}
96
97static int ceph_x_decrypt(struct ceph_crypto_key *secret, void **p, void *end)
98{
99	int ciphertext_len;
100	int ret;
101
102	ceph_decode_32_safe(p, end, ciphertext_len, e_inval);
103	ceph_decode_need(p, end, ciphertext_len, e_inval);
104
105	ret = __ceph_x_decrypt(secret, *p, ciphertext_len);
106	if (ret < 0)
107		return ret;
108
109	*p += ciphertext_len;
110	return ret;
111
112e_inval:
113	return -EINVAL;
114}
115
116/*
117 * get existing (or insert new) ticket handler
118 */
119static struct ceph_x_ticket_handler *
120get_ticket_handler(struct ceph_auth_client *ac, int service)
121{
122	struct ceph_x_ticket_handler *th;
123	struct ceph_x_info *xi = ac->private;
124	struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node;
125
126	while (*p) {
127		parent = *p;
128		th = rb_entry(parent, struct ceph_x_ticket_handler, node);
129		if (service < th->service)
130			p = &(*p)->rb_left;
131		else if (service > th->service)
132			p = &(*p)->rb_right;
133		else
134			return th;
135	}
136
137	/* add it */
138	th = kzalloc(sizeof(*th), GFP_NOFS);
139	if (!th)
140		return ERR_PTR(-ENOMEM);
141	th->service = service;
142	rb_link_node(&th->node, parent, p);
143	rb_insert_color(&th->node, &xi->ticket_handlers);
144	return th;
145}
146
147static void remove_ticket_handler(struct ceph_auth_client *ac,
148				  struct ceph_x_ticket_handler *th)
149{
150	struct ceph_x_info *xi = ac->private;
151
152	dout("remove_ticket_handler %p %d\n", th, th->service);
153	rb_erase(&th->node, &xi->ticket_handlers);
154	ceph_crypto_key_destroy(&th->session_key);
155	if (th->ticket_blob)
156		ceph_buffer_put(th->ticket_blob);
157	kfree(th);
158}
159
160static int process_one_ticket(struct ceph_auth_client *ac,
161			      struct ceph_crypto_key *secret,
162			      void **p, void *end)
163{
164	struct ceph_x_info *xi = ac->private;
165	int type;
166	u8 tkt_struct_v, blob_struct_v;
167	struct ceph_x_ticket_handler *th;
168	void *dp, *dend;
169	int dlen;
170	char is_enc;
171	struct timespec64 validity;
172	void *tp, *tpend;
173	void **ptp;
174	struct ceph_crypto_key new_session_key = { 0 };
175	struct ceph_buffer *new_ticket_blob;
176	time64_t new_expires, new_renew_after;
177	u64 new_secret_id;
178	int ret;
179
180	ceph_decode_need(p, end, sizeof(u32) + 1, bad);
181
182	type = ceph_decode_32(p);
183	dout(" ticket type %d %s\n", type, ceph_entity_type_name(type));
184
185	tkt_struct_v = ceph_decode_8(p);
186	if (tkt_struct_v != 1)
187		goto bad;
188
189	th = get_ticket_handler(ac, type);
190	if (IS_ERR(th)) {
191		ret = PTR_ERR(th);
192		goto out;
193	}
194
195	/* blob for me */
196	dp = *p + ceph_x_encrypt_offset();
197	ret = ceph_x_decrypt(secret, p, end);
198	if (ret < 0)
199		goto out;
200	dout(" decrypted %d bytes\n", ret);
201	dend = dp + ret;
202
203	ceph_decode_8_safe(&dp, dend, tkt_struct_v, bad);
204	if (tkt_struct_v != 1)
205		goto bad;
206
207	ret = ceph_crypto_key_decode(&new_session_key, &dp, dend);
208	if (ret)
209		goto out;
210
211	ceph_decode_need(&dp, dend, sizeof(struct ceph_timespec), bad);
212	ceph_decode_timespec64(&validity, dp);
213	dp += sizeof(struct ceph_timespec);
214	new_expires = ktime_get_real_seconds() + validity.tv_sec;
215	new_renew_after = new_expires - (validity.tv_sec / 4);
216	dout(" expires=%llu renew_after=%llu\n", new_expires,
217	     new_renew_after);
218
219	/* ticket blob for service */
220	ceph_decode_8_safe(p, end, is_enc, bad);
221	if (is_enc) {
222		/* encrypted */
223		tp = *p + ceph_x_encrypt_offset();
224		ret = ceph_x_decrypt(&th->session_key, p, end);
225		if (ret < 0)
226			goto out;
227		dout(" encrypted ticket, decrypted %d bytes\n", ret);
228		ptp = &tp;
229		tpend = tp + ret;
230	} else {
231		/* unencrypted */
232		ptp = p;
233		tpend = end;
234	}
235	ceph_decode_32_safe(ptp, tpend, dlen, bad);
236	dout(" ticket blob is %d bytes\n", dlen);
237	ceph_decode_need(ptp, tpend, 1 + sizeof(u64), bad);
238	blob_struct_v = ceph_decode_8(ptp);
239	if (blob_struct_v != 1)
240		goto bad;
241
242	new_secret_id = ceph_decode_64(ptp);
243	ret = ceph_decode_buffer(&new_ticket_blob, ptp, tpend);
244	if (ret)
245		goto out;
246
247	/* all is well, update our ticket */
248	ceph_crypto_key_destroy(&th->session_key);
249	if (th->ticket_blob)
250		ceph_buffer_put(th->ticket_blob);
251	th->session_key = new_session_key;
252	th->ticket_blob = new_ticket_blob;
253	th->secret_id = new_secret_id;
254	th->expires = new_expires;
255	th->renew_after = new_renew_after;
256	th->have_key = true;
257	dout(" got ticket service %d (%s) secret_id %lld len %d\n",
258	     type, ceph_entity_type_name(type), th->secret_id,
259	     (int)th->ticket_blob->vec.iov_len);
260	xi->have_keys |= th->service;
261	return 0;
262
263bad:
264	ret = -EINVAL;
265out:
266	ceph_crypto_key_destroy(&new_session_key);
267	return ret;
268}
269
270static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac,
271				    struct ceph_crypto_key *secret,
272				    void **p, void *end)
273{
274	u8 reply_struct_v;
275	u32 num;
276	int ret;
277
278	ceph_decode_8_safe(p, end, reply_struct_v, bad);
279	if (reply_struct_v != 1)
280		return -EINVAL;
281
282	ceph_decode_32_safe(p, end, num, bad);
283	dout("%d tickets\n", num);
284
285	while (num--) {
286		ret = process_one_ticket(ac, secret, p, end);
287		if (ret)
288			return ret;
289	}
290
291	return 0;
292
293bad:
294	return -EINVAL;
295}
296
297/*
298 * Encode and encrypt the second part (ceph_x_authorize_b) of the
299 * authorizer.  The first part (ceph_x_authorize_a) should already be
300 * encoded.
301 */
302static int encrypt_authorizer(struct ceph_x_authorizer *au,
303			      u64 *server_challenge)
304{
305	struct ceph_x_authorize_a *msg_a;
306	struct ceph_x_authorize_b *msg_b;
307	void *p, *end;
308	int ret;
309
310	msg_a = au->buf->vec.iov_base;
311	WARN_ON(msg_a->ticket_blob.secret_id != cpu_to_le64(au->secret_id));
312	p = (void *)(msg_a + 1) + le32_to_cpu(msg_a->ticket_blob.blob_len);
313	end = au->buf->vec.iov_base + au->buf->vec.iov_len;
314
315	msg_b = p + ceph_x_encrypt_offset();
316	msg_b->struct_v = 2;
317	msg_b->nonce = cpu_to_le64(au->nonce);
318	if (server_challenge) {
319		msg_b->have_challenge = 1;
320		msg_b->server_challenge_plus_one =
321		    cpu_to_le64(*server_challenge + 1);
322	} else {
323		msg_b->have_challenge = 0;
324		msg_b->server_challenge_plus_one = 0;
325	}
326
327	ret = ceph_x_encrypt(&au->session_key, p, end - p, sizeof(*msg_b));
328	if (ret < 0)
329		return ret;
330
331	p += ret;
332	if (server_challenge) {
333		WARN_ON(p != end);
334	} else {
335		WARN_ON(p > end);
336		au->buf->vec.iov_len = p - au->buf->vec.iov_base;
337	}
338
339	return 0;
340}
341
342static void ceph_x_authorizer_cleanup(struct ceph_x_authorizer *au)
343{
344	ceph_crypto_key_destroy(&au->session_key);
345	if (au->buf) {
346		ceph_buffer_put(au->buf);
347		au->buf = NULL;
348	}
349}
350
351static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
352				   struct ceph_x_ticket_handler *th,
353				   struct ceph_x_authorizer *au)
354{
355	int maxlen;
356	struct ceph_x_authorize_a *msg_a;
357	struct ceph_x_authorize_b *msg_b;
358	int ret;
359	int ticket_blob_len =
360		(th->ticket_blob ? th->ticket_blob->vec.iov_len : 0);
361
362	dout("build_authorizer for %s %p\n",
363	     ceph_entity_type_name(th->service), au);
364
365	ceph_crypto_key_destroy(&au->session_key);
366	ret = ceph_crypto_key_clone(&au->session_key, &th->session_key);
367	if (ret)
368		goto out_au;
369
370	maxlen = sizeof(*msg_a) + ticket_blob_len +
371		ceph_x_encrypt_buflen(sizeof(*msg_b));
372	dout("  need len %d\n", maxlen);
373	if (au->buf && au->buf->alloc_len < maxlen) {
374		ceph_buffer_put(au->buf);
375		au->buf = NULL;
376	}
377	if (!au->buf) {
378		au->buf = ceph_buffer_new(maxlen, GFP_NOFS);
379		if (!au->buf) {
380			ret = -ENOMEM;
381			goto out_au;
382		}
383	}
384	au->service = th->service;
385	WARN_ON(!th->secret_id);
386	au->secret_id = th->secret_id;
387
388	msg_a = au->buf->vec.iov_base;
389	msg_a->struct_v = 1;
390	msg_a->global_id = cpu_to_le64(ac->global_id);
391	msg_a->service_id = cpu_to_le32(th->service);
392	msg_a->ticket_blob.struct_v = 1;
393	msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id);
394	msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len);
395	if (ticket_blob_len) {
396		memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base,
397		       th->ticket_blob->vec.iov_len);
398	}
399	dout(" th %p secret_id %lld %lld\n", th, th->secret_id,
400	     le64_to_cpu(msg_a->ticket_blob.secret_id));
401
402	get_random_bytes(&au->nonce, sizeof(au->nonce));
403	ret = encrypt_authorizer(au, NULL);
404	if (ret) {
405		pr_err("failed to encrypt authorizer: %d", ret);
406		goto out_au;
407	}
408
409	dout(" built authorizer nonce %llx len %d\n", au->nonce,
410	     (int)au->buf->vec.iov_len);
411	return 0;
412
413out_au:
414	ceph_x_authorizer_cleanup(au);
415	return ret;
416}
417
418static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th,
419				void **p, void *end)
420{
421	ceph_decode_need(p, end, 1 + sizeof(u64), bad);
422	ceph_encode_8(p, 1);
423	ceph_encode_64(p, th->secret_id);
424	if (th->ticket_blob) {
425		const char *buf = th->ticket_blob->vec.iov_base;
426		u32 len = th->ticket_blob->vec.iov_len;
427
428		ceph_encode_32_safe(p, end, len, bad);
429		ceph_encode_copy_safe(p, end, buf, len, bad);
430	} else {
431		ceph_encode_32_safe(p, end, 0, bad);
432	}
433
434	return 0;
435bad:
436	return -ERANGE;
437}
438
439static bool need_key(struct ceph_x_ticket_handler *th)
440{
441	if (!th->have_key)
442		return true;
443
444	return ktime_get_real_seconds() >= th->renew_after;
445}
446
447static bool have_key(struct ceph_x_ticket_handler *th)
448{
449	if (th->have_key && ktime_get_real_seconds() >= th->expires) {
450		dout("ticket %d (%s) secret_id %llu expired\n", th->service,
451		     ceph_entity_type_name(th->service), th->secret_id);
452		th->have_key = false;
453	}
454
455	return th->have_key;
456}
457
458static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed)
459{
460	int want = ac->want_keys;
461	struct ceph_x_info *xi = ac->private;
462	int service;
463
464	*pneed = ac->want_keys & ~(xi->have_keys);
465
466	for (service = 1; service <= want; service <<= 1) {
467		struct ceph_x_ticket_handler *th;
468
469		if (!(ac->want_keys & service))
470			continue;
471
472		if (*pneed & service)
473			continue;
474
475		th = get_ticket_handler(ac, service);
476		if (IS_ERR(th)) {
477			*pneed |= service;
478			continue;
479		}
480
481		if (need_key(th))
482			*pneed |= service;
483		if (!have_key(th))
484			xi->have_keys &= ~service;
485	}
486}
487
488static int ceph_x_build_request(struct ceph_auth_client *ac,
489				void *buf, void *end)
490{
491	struct ceph_x_info *xi = ac->private;
492	int need;
493	struct ceph_x_request_header *head = buf;
494	void *p;
495	int ret;
496	struct ceph_x_ticket_handler *th =
497		get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
498
499	if (IS_ERR(th))
500		return PTR_ERR(th);
501
502	ceph_x_validate_tickets(ac, &need);
503	dout("%s want 0x%x have 0x%x need 0x%x\n", __func__, ac->want_keys,
504	     xi->have_keys, need);
505
506	if (need & CEPH_ENTITY_TYPE_AUTH) {
507		struct ceph_x_authenticate *auth = (void *)(head + 1);
508		void *enc_buf = xi->auth_authorizer.enc_buf;
509		struct ceph_x_challenge_blob *blob = enc_buf +
510							ceph_x_encrypt_offset();
511		u64 *u;
512
513		p = auth + 1;
514		if (p > end)
515			return -ERANGE;
516
517		dout(" get_auth_session_key\n");
518		head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY);
519
520		/* encrypt and hash */
521		get_random_bytes(&auth->client_challenge, sizeof(u64));
522		blob->client_challenge = auth->client_challenge;
523		blob->server_challenge = cpu_to_le64(xi->server_challenge);
524		ret = ceph_x_encrypt(&xi->secret, enc_buf, CEPHX_AU_ENC_BUF_LEN,
525				     sizeof(*blob));
526		if (ret < 0)
527			return ret;
528
529		auth->struct_v = 3;  /* nautilus+ */
530		auth->key = 0;
531		for (u = (u64 *)enc_buf; u + 1 <= (u64 *)(enc_buf + ret); u++)
532			auth->key ^= *(__le64 *)u;
533		dout(" server_challenge %llx client_challenge %llx key %llx\n",
534		     xi->server_challenge, le64_to_cpu(auth->client_challenge),
535		     le64_to_cpu(auth->key));
536
537		/* now encode the old ticket if exists */
538		ret = ceph_x_encode_ticket(th, &p, end);
539		if (ret < 0)
540			return ret;
541
542		/* nautilus+: request service tickets at the same time */
543		need = ac->want_keys & ~CEPH_ENTITY_TYPE_AUTH;
544		WARN_ON(!need);
545		ceph_encode_32_safe(&p, end, need, e_range);
546		return p - buf;
547	}
548
549	if (need) {
550		dout(" get_principal_session_key\n");
551		ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer);
552		if (ret)
553			return ret;
554
555		p = buf;
556		ceph_encode_16_safe(&p, end, CEPHX_GET_PRINCIPAL_SESSION_KEY,
557				    e_range);
558		ceph_encode_copy_safe(&p, end,
559			xi->auth_authorizer.buf->vec.iov_base,
560			xi->auth_authorizer.buf->vec.iov_len, e_range);
561		ceph_encode_8_safe(&p, end, 1, e_range);
562		ceph_encode_32_safe(&p, end, need, e_range);
563		return p - buf;
564	}
565
566	return 0;
567
568e_range:
569	return -ERANGE;
570}
571
572static int decode_con_secret(void **p, void *end, u8 *con_secret,
573			     int *con_secret_len)
574{
575	int len;
576
577	ceph_decode_32_safe(p, end, len, bad);
578	ceph_decode_need(p, end, len, bad);
579
580	dout("%s len %d\n", __func__, len);
581	if (con_secret) {
582		if (len > CEPH_MAX_CON_SECRET_LEN) {
583			pr_err("connection secret too big %d\n", len);
584			goto bad_memzero;
585		}
586		memcpy(con_secret, *p, len);
587		*con_secret_len = len;
588	}
589	memzero_explicit(*p, len);
590	*p += len;
591	return 0;
592
593bad_memzero:
594	memzero_explicit(*p, len);
595bad:
596	pr_err("failed to decode connection secret\n");
597	return -EINVAL;
598}
599
600static int handle_auth_session_key(struct ceph_auth_client *ac, u64 global_id,
601				   void **p, void *end,
602				   u8 *session_key, int *session_key_len,
603				   u8 *con_secret, int *con_secret_len)
604{
605	struct ceph_x_info *xi = ac->private;
606	struct ceph_x_ticket_handler *th;
607	void *dp, *dend;
608	int len;
609	int ret;
610
611	/* AUTH ticket */
612	ret = ceph_x_proc_ticket_reply(ac, &xi->secret, p, end);
613	if (ret)
614		return ret;
615
616	ceph_auth_set_global_id(ac, global_id);
617	if (*p == end) {
618		/* pre-nautilus (or didn't request service tickets!) */
619		WARN_ON(session_key || con_secret);
620		return 0;
621	}
622
623	th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
624	if (IS_ERR(th))
625		return PTR_ERR(th);
626
627	if (session_key) {
628		memcpy(session_key, th->session_key.key, th->session_key.len);
629		*session_key_len = th->session_key.len;
630	}
631
632	/* connection secret */
633	ceph_decode_32_safe(p, end, len, e_inval);
634	dout("%s connection secret blob len %d\n", __func__, len);
635	if (len > 0) {
636		dp = *p + ceph_x_encrypt_offset();
637		ret = ceph_x_decrypt(&th->session_key, p, *p + len);
638		if (ret < 0)
639			return ret;
640
641		dout("%s decrypted %d bytes\n", __func__, ret);
642		dend = dp + ret;
643
644		ret = decode_con_secret(&dp, dend, con_secret, con_secret_len);
645		if (ret)
646			return ret;
647	}
648
649	/* service tickets */
650	ceph_decode_32_safe(p, end, len, e_inval);
651	dout("%s service tickets blob len %d\n", __func__, len);
652	if (len > 0) {
653		ret = ceph_x_proc_ticket_reply(ac, &th->session_key,
654					       p, *p + len);
655		if (ret)
656			return ret;
657	}
658
659	return 0;
660
661e_inval:
662	return -EINVAL;
663}
664
665static int ceph_x_handle_reply(struct ceph_auth_client *ac, u64 global_id,
666			       void *buf, void *end,
667			       u8 *session_key, int *session_key_len,
668			       u8 *con_secret, int *con_secret_len)
669{
670	struct ceph_x_info *xi = ac->private;
671	struct ceph_x_ticket_handler *th;
672	int len = end - buf;
673	int result;
674	void *p;
675	int op;
676	int ret;
677
678	if (xi->starting) {
679		/* it's a hello */
680		struct ceph_x_server_challenge *sc = buf;
681
682		if (len != sizeof(*sc))
683			return -EINVAL;
684		xi->server_challenge = le64_to_cpu(sc->server_challenge);
685		dout("handle_reply got server challenge %llx\n",
686		     xi->server_challenge);
687		xi->starting = false;
688		xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH;
689		return -EAGAIN;
690	}
691
692	p = buf;
693	ceph_decode_16_safe(&p, end, op, e_inval);
694	ceph_decode_32_safe(&p, end, result, e_inval);
695	dout("handle_reply op %d result %d\n", op, result);
696	switch (op) {
697	case CEPHX_GET_AUTH_SESSION_KEY:
698		/* AUTH ticket + [connection secret] + service tickets */
699		ret = handle_auth_session_key(ac, global_id, &p, end,
700					      session_key, session_key_len,
701					      con_secret, con_secret_len);
702		break;
703
704	case CEPHX_GET_PRINCIPAL_SESSION_KEY:
705		th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
706		if (IS_ERR(th))
707			return PTR_ERR(th);
708
709		/* service tickets */
710		ret = ceph_x_proc_ticket_reply(ac, &th->session_key, &p, end);
711		break;
712
713	default:
714		return -EINVAL;
715	}
716	if (ret)
717		return ret;
718	if (ac->want_keys == xi->have_keys)
719		return 0;
720	return -EAGAIN;
721
722e_inval:
723	return -EINVAL;
724}
725
726static void ceph_x_destroy_authorizer(struct ceph_authorizer *a)
727{
728	struct ceph_x_authorizer *au = (void *)a;
729
730	ceph_x_authorizer_cleanup(au);
731	kfree(au);
732}
733
734static int ceph_x_create_authorizer(
735	struct ceph_auth_client *ac, int peer_type,
736	struct ceph_auth_handshake *auth)
737{
738	struct ceph_x_authorizer *au;
739	struct ceph_x_ticket_handler *th;
740	int ret;
741
742	th = get_ticket_handler(ac, peer_type);
743	if (IS_ERR(th))
744		return PTR_ERR(th);
745
746	au = kzalloc(sizeof(*au), GFP_NOFS);
747	if (!au)
748		return -ENOMEM;
749
750	au->base.destroy = ceph_x_destroy_authorizer;
751
752	ret = ceph_x_build_authorizer(ac, th, au);
753	if (ret) {
754		kfree(au);
755		return ret;
756	}
757
758	auth->authorizer = (struct ceph_authorizer *) au;
759	auth->authorizer_buf = au->buf->vec.iov_base;
760	auth->authorizer_buf_len = au->buf->vec.iov_len;
761	auth->authorizer_reply_buf = au->enc_buf;
762	auth->authorizer_reply_buf_len = CEPHX_AU_ENC_BUF_LEN;
763	auth->sign_message = ac->ops->sign_message;
764	auth->check_message_signature = ac->ops->check_message_signature;
765
766	return 0;
767}
768
769static int ceph_x_update_authorizer(
770	struct ceph_auth_client *ac, int peer_type,
771	struct ceph_auth_handshake *auth)
772{
773	struct ceph_x_authorizer *au;
774	struct ceph_x_ticket_handler *th;
775
776	th = get_ticket_handler(ac, peer_type);
777	if (IS_ERR(th))
778		return PTR_ERR(th);
779
780	au = (struct ceph_x_authorizer *)auth->authorizer;
781	if (au->secret_id < th->secret_id) {
782		dout("ceph_x_update_authorizer service %u secret %llu < %llu\n",
783		     au->service, au->secret_id, th->secret_id);
784		return ceph_x_build_authorizer(ac, th, au);
785	}
786	return 0;
787}
788
789/*
790 * CephXAuthorizeChallenge
791 */
792static int decrypt_authorizer_challenge(struct ceph_crypto_key *secret,
793					void *challenge, int challenge_len,
794					u64 *server_challenge)
795{
796	void *dp, *dend;
797	int ret;
798
799	/* no leading len */
800	ret = __ceph_x_decrypt(secret, challenge, challenge_len);
801	if (ret < 0)
802		return ret;
803
804	dout("%s decrypted %d bytes\n", __func__, ret);
805	dp = challenge + sizeof(struct ceph_x_encrypt_header);
806	dend = dp + ret;
807
808	ceph_decode_skip_8(&dp, dend, e_inval);  /* struct_v */
809	ceph_decode_64_safe(&dp, dend, *server_challenge, e_inval);
810	dout("%s server_challenge %llu\n", __func__, *server_challenge);
811	return 0;
812
813e_inval:
814	return -EINVAL;
815}
816
817static int ceph_x_add_authorizer_challenge(struct ceph_auth_client *ac,
818					   struct ceph_authorizer *a,
819					   void *challenge, int challenge_len)
820{
821	struct ceph_x_authorizer *au = (void *)a;
822	u64 server_challenge;
823	int ret;
824
825	ret = decrypt_authorizer_challenge(&au->session_key, challenge,
826					   challenge_len, &server_challenge);
827	if (ret) {
828		pr_err("failed to decrypt authorize challenge: %d", ret);
829		return ret;
830	}
831
832	ret = encrypt_authorizer(au, &server_challenge);
833	if (ret) {
834		pr_err("failed to encrypt authorizer w/ challenge: %d", ret);
835		return ret;
836	}
837
838	return 0;
839}
840
841/*
842 * CephXAuthorizeReply
843 */
844static int decrypt_authorizer_reply(struct ceph_crypto_key *secret,
845				    void **p, void *end, u64 *nonce_plus_one,
846				    u8 *con_secret, int *con_secret_len)
847{
848	void *dp, *dend;
849	u8 struct_v;
850	int ret;
851
852	dp = *p + ceph_x_encrypt_offset();
853	ret = ceph_x_decrypt(secret, p, end);
854	if (ret < 0)
855		return ret;
856
857	dout("%s decrypted %d bytes\n", __func__, ret);
858	dend = dp + ret;
859
860	ceph_decode_8_safe(&dp, dend, struct_v, e_inval);
861	ceph_decode_64_safe(&dp, dend, *nonce_plus_one, e_inval);
862	dout("%s nonce_plus_one %llu\n", __func__, *nonce_plus_one);
863	if (struct_v >= 2) {
864		ret = decode_con_secret(&dp, dend, con_secret, con_secret_len);
865		if (ret)
866			return ret;
867	}
868
869	return 0;
870
871e_inval:
872	return -EINVAL;
873}
874
875static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac,
876					  struct ceph_authorizer *a,
877					  void *reply, int reply_len,
878					  u8 *session_key, int *session_key_len,
879					  u8 *con_secret, int *con_secret_len)
880{
881	struct ceph_x_authorizer *au = (void *)a;
882	u64 nonce_plus_one;
883	int ret;
884
885	if (session_key) {
886		memcpy(session_key, au->session_key.key, au->session_key.len);
887		*session_key_len = au->session_key.len;
888	}
889
890	ret = decrypt_authorizer_reply(&au->session_key, &reply,
891				       reply + reply_len, &nonce_plus_one,
892				       con_secret, con_secret_len);
893	if (ret)
894		return ret;
895
896	if (nonce_plus_one != au->nonce + 1) {
897		pr_err("failed to authenticate server\n");
898		return -EPERM;
899	}
900
901	return 0;
902}
903
904static void ceph_x_reset(struct ceph_auth_client *ac)
905{
906	struct ceph_x_info *xi = ac->private;
907
908	dout("reset\n");
909	xi->starting = true;
910	xi->server_challenge = 0;
911}
912
913static void ceph_x_destroy(struct ceph_auth_client *ac)
914{
915	struct ceph_x_info *xi = ac->private;
916	struct rb_node *p;
917
918	dout("ceph_x_destroy %p\n", ac);
919	ceph_crypto_key_destroy(&xi->secret);
920
921	while ((p = rb_first(&xi->ticket_handlers)) != NULL) {
922		struct ceph_x_ticket_handler *th =
923			rb_entry(p, struct ceph_x_ticket_handler, node);
924		remove_ticket_handler(ac, th);
925	}
926
927	ceph_x_authorizer_cleanup(&xi->auth_authorizer);
928
929	kfree(ac->private);
930	ac->private = NULL;
931}
932
933static void invalidate_ticket(struct ceph_auth_client *ac, int peer_type)
934{
935	struct ceph_x_ticket_handler *th;
936
937	th = get_ticket_handler(ac, peer_type);
938	if (IS_ERR(th))
939		return;
940
941	if (th->have_key) {
942		dout("ticket %d (%s) secret_id %llu invalidated\n",
943		     th->service, ceph_entity_type_name(th->service),
944		     th->secret_id);
945		th->have_key = false;
946	}
947}
948
949static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac,
950					 int peer_type)
951{
952	/*
953	 * We are to invalidate a service ticket in the hopes of
954	 * getting a new, hopefully more valid, one.  But, we won't get
955	 * it unless our AUTH ticket is good, so invalidate AUTH ticket
956	 * as well, just in case.
957	 */
958	invalidate_ticket(ac, peer_type);
959	invalidate_ticket(ac, CEPH_ENTITY_TYPE_AUTH);
960}
961
962static int calc_signature(struct ceph_x_authorizer *au, struct ceph_msg *msg,
963			  __le64 *psig)
964{
965	void *enc_buf = au->enc_buf;
966	int ret;
967
968	if (!CEPH_HAVE_FEATURE(msg->con->peer_features, CEPHX_V2)) {
969		struct {
970			__le32 len;
971			__le32 header_crc;
972			__le32 front_crc;
973			__le32 middle_crc;
974			__le32 data_crc;
975		} __packed *sigblock = enc_buf + ceph_x_encrypt_offset();
976
977		sigblock->len = cpu_to_le32(4*sizeof(u32));
978		sigblock->header_crc = msg->hdr.crc;
979		sigblock->front_crc = msg->footer.front_crc;
980		sigblock->middle_crc = msg->footer.middle_crc;
981		sigblock->data_crc =  msg->footer.data_crc;
982
983		ret = ceph_x_encrypt(&au->session_key, enc_buf,
984				     CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock));
985		if (ret < 0)
986			return ret;
987
988		*psig = *(__le64 *)(enc_buf + sizeof(u32));
989	} else {
990		struct {
991			__le32 header_crc;
992			__le32 front_crc;
993			__le32 front_len;
994			__le32 middle_crc;
995			__le32 middle_len;
996			__le32 data_crc;
997			__le32 data_len;
998			__le32 seq_lower_word;
999		} __packed *sigblock = enc_buf;
1000		struct {
1001			__le64 a, b, c, d;
1002		} __packed *penc = enc_buf;
1003		int ciphertext_len;
1004
1005		sigblock->header_crc = msg->hdr.crc;
1006		sigblock->front_crc = msg->footer.front_crc;
1007		sigblock->front_len = msg->hdr.front_len;
1008		sigblock->middle_crc = msg->footer.middle_crc;
1009		sigblock->middle_len = msg->hdr.middle_len;
1010		sigblock->data_crc =  msg->footer.data_crc;
1011		sigblock->data_len = msg->hdr.data_len;
1012		sigblock->seq_lower_word = *(__le32 *)&msg->hdr.seq;
1013
1014		/* no leading len, no ceph_x_encrypt_header */
1015		ret = ceph_crypt(&au->session_key, true, enc_buf,
1016				 CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock),
1017				 &ciphertext_len);
1018		if (ret)
1019			return ret;
1020
1021		*psig = penc->a ^ penc->b ^ penc->c ^ penc->d;
1022	}
1023
1024	return 0;
1025}
1026
1027static int ceph_x_sign_message(struct ceph_auth_handshake *auth,
1028			       struct ceph_msg *msg)
1029{
1030	__le64 sig;
1031	int ret;
1032
1033	if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
1034		return 0;
1035
1036	ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer,
1037			     msg, &sig);
1038	if (ret)
1039		return ret;
1040
1041	msg->footer.sig = sig;
1042	msg->footer.flags |= CEPH_MSG_FOOTER_SIGNED;
1043	return 0;
1044}
1045
1046static int ceph_x_check_message_signature(struct ceph_auth_handshake *auth,
1047					  struct ceph_msg *msg)
1048{
1049	__le64 sig_check;
1050	int ret;
1051
1052	if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
1053		return 0;
1054
1055	ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer,
1056			     msg, &sig_check);
1057	if (ret)
1058		return ret;
1059	if (sig_check == msg->footer.sig)
1060		return 0;
1061	if (msg->footer.flags & CEPH_MSG_FOOTER_SIGNED)
1062		dout("ceph_x_check_message_signature %p has signature %llx "
1063		     "expect %llx\n", msg, msg->footer.sig, sig_check);
1064	else
1065		dout("ceph_x_check_message_signature %p sender did not set "
1066		     "CEPH_MSG_FOOTER_SIGNED\n", msg);
1067	return -EBADMSG;
1068}
1069
1070static const struct ceph_auth_client_ops ceph_x_ops = {
1071	.is_authenticated = ceph_x_is_authenticated,
1072	.should_authenticate = ceph_x_should_authenticate,
1073	.build_request = ceph_x_build_request,
1074	.handle_reply = ceph_x_handle_reply,
1075	.create_authorizer = ceph_x_create_authorizer,
1076	.update_authorizer = ceph_x_update_authorizer,
1077	.add_authorizer_challenge = ceph_x_add_authorizer_challenge,
1078	.verify_authorizer_reply = ceph_x_verify_authorizer_reply,
1079	.invalidate_authorizer = ceph_x_invalidate_authorizer,
1080	.reset =  ceph_x_reset,
1081	.destroy = ceph_x_destroy,
1082	.sign_message = ceph_x_sign_message,
1083	.check_message_signature = ceph_x_check_message_signature,
1084};
1085
1086
1087int ceph_x_init(struct ceph_auth_client *ac)
1088{
1089	struct ceph_x_info *xi;
1090	int ret;
1091
1092	dout("ceph_x_init %p\n", ac);
1093	ret = -ENOMEM;
1094	xi = kzalloc(sizeof(*xi), GFP_NOFS);
1095	if (!xi)
1096		goto out;
1097
1098	ret = -EINVAL;
1099	if (!ac->key) {
1100		pr_err("no secret set (for auth_x protocol)\n");
1101		goto out_nomem;
1102	}
1103
1104	ret = ceph_crypto_key_clone(&xi->secret, ac->key);
1105	if (ret < 0) {
1106		pr_err("cannot clone key: %d\n", ret);
1107		goto out_nomem;
1108	}
1109
1110	xi->starting = true;
1111	xi->ticket_handlers = RB_ROOT;
1112
1113	ac->protocol = CEPH_AUTH_CEPHX;
1114	ac->private = xi;
1115	ac->ops = &ceph_x_ops;
1116	return 0;
1117
1118out_nomem:
1119	kfree(xi);
1120out:
1121	return ret;
1122}
1123