1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2020 Hannes Reinecke, SUSE Linux
4 */
5
6#include <linux/crc32.h>
7#include <linux/base64.h>
8#include <linux/prandom.h>
9#include <asm/unaligned.h>
10#include <crypto/hash.h>
11#include <crypto/dh.h>
12#include "nvme.h"
13#include "fabrics.h"
14#include <linux/nvme-auth.h>
15
16#define CHAP_BUF_SIZE 4096
17static struct kmem_cache *nvme_chap_buf_cache;
18static mempool_t *nvme_chap_buf_pool;
19
20struct nvme_dhchap_queue_context {
21	struct list_head entry;
22	struct work_struct auth_work;
23	struct nvme_ctrl *ctrl;
24	struct crypto_shash *shash_tfm;
25	struct crypto_kpp *dh_tfm;
26	struct nvme_dhchap_key *transformed_key;
27	void *buf;
28	int qid;
29	int error;
30	u32 s1;
31	u32 s2;
32	bool bi_directional;
33	u16 transaction;
34	u8 status;
35	u8 dhgroup_id;
36	u8 hash_id;
37	size_t hash_len;
38	u8 c1[64];
39	u8 c2[64];
40	u8 response[64];
41	u8 *ctrl_key;
42	u8 *host_key;
43	u8 *sess_key;
44	int ctrl_key_len;
45	int host_key_len;
46	int sess_key_len;
47};
48
49static struct workqueue_struct *nvme_auth_wq;
50
51static inline int ctrl_max_dhchaps(struct nvme_ctrl *ctrl)
52{
53	return ctrl->opts->nr_io_queues + ctrl->opts->nr_write_queues +
54			ctrl->opts->nr_poll_queues + 1;
55}
56
57static int nvme_auth_submit(struct nvme_ctrl *ctrl, int qid,
58			    void *data, size_t data_len, bool auth_send)
59{
60	struct nvme_command cmd = {};
61	nvme_submit_flags_t flags = NVME_SUBMIT_RETRY;
62	struct request_queue *q = ctrl->fabrics_q;
63	int ret;
64
65	if (qid != 0) {
66		flags |= NVME_SUBMIT_NOWAIT | NVME_SUBMIT_RESERVED;
67		q = ctrl->connect_q;
68	}
69
70	cmd.auth_common.opcode = nvme_fabrics_command;
71	cmd.auth_common.secp = NVME_AUTH_DHCHAP_PROTOCOL_IDENTIFIER;
72	cmd.auth_common.spsp0 = 0x01;
73	cmd.auth_common.spsp1 = 0x01;
74	if (auth_send) {
75		cmd.auth_send.fctype = nvme_fabrics_type_auth_send;
76		cmd.auth_send.tl = cpu_to_le32(data_len);
77	} else {
78		cmd.auth_receive.fctype = nvme_fabrics_type_auth_receive;
79		cmd.auth_receive.al = cpu_to_le32(data_len);
80	}
81
82	ret = __nvme_submit_sync_cmd(q, &cmd, NULL, data, data_len,
83				     qid == 0 ? NVME_QID_ANY : qid, flags);
84	if (ret > 0)
85		dev_warn(ctrl->device,
86			"qid %d auth_send failed with status %d\n", qid, ret);
87	else if (ret < 0)
88		dev_err(ctrl->device,
89			"qid %d auth_send failed with error %d\n", qid, ret);
90	return ret;
91}
92
93static int nvme_auth_receive_validate(struct nvme_ctrl *ctrl, int qid,
94		struct nvmf_auth_dhchap_failure_data *data,
95		u16 transaction, u8 expected_msg)
96{
97	dev_dbg(ctrl->device, "%s: qid %d auth_type %d auth_id %x\n",
98		__func__, qid, data->auth_type, data->auth_id);
99
100	if (data->auth_type == NVME_AUTH_COMMON_MESSAGES &&
101	    data->auth_id == NVME_AUTH_DHCHAP_MESSAGE_FAILURE1) {
102		return data->rescode_exp;
103	}
104	if (data->auth_type != NVME_AUTH_DHCHAP_MESSAGES ||
105	    data->auth_id != expected_msg) {
106		dev_warn(ctrl->device,
107			 "qid %d invalid message %02x/%02x\n",
108			 qid, data->auth_type, data->auth_id);
109		return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_MESSAGE;
110	}
111	if (le16_to_cpu(data->t_id) != transaction) {
112		dev_warn(ctrl->device,
113			 "qid %d invalid transaction ID %d\n",
114			 qid, le16_to_cpu(data->t_id));
115		return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_MESSAGE;
116	}
117	return 0;
118}
119
120static int nvme_auth_set_dhchap_negotiate_data(struct nvme_ctrl *ctrl,
121		struct nvme_dhchap_queue_context *chap)
122{
123	struct nvmf_auth_dhchap_negotiate_data *data = chap->buf;
124	size_t size = sizeof(*data) + sizeof(union nvmf_auth_protocol);
125
126	if (size > CHAP_BUF_SIZE) {
127		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
128		return -EINVAL;
129	}
130	memset((u8 *)chap->buf, 0, size);
131	data->auth_type = NVME_AUTH_COMMON_MESSAGES;
132	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_NEGOTIATE;
133	data->t_id = cpu_to_le16(chap->transaction);
134	data->sc_c = 0; /* No secure channel concatenation */
135	data->napd = 1;
136	data->auth_protocol[0].dhchap.authid = NVME_AUTH_DHCHAP_AUTH_ID;
137	data->auth_protocol[0].dhchap.halen = 3;
138	data->auth_protocol[0].dhchap.dhlen = 6;
139	data->auth_protocol[0].dhchap.idlist[0] = NVME_AUTH_HASH_SHA256;
140	data->auth_protocol[0].dhchap.idlist[1] = NVME_AUTH_HASH_SHA384;
141	data->auth_protocol[0].dhchap.idlist[2] = NVME_AUTH_HASH_SHA512;
142	data->auth_protocol[0].dhchap.idlist[30] = NVME_AUTH_DHGROUP_NULL;
143	data->auth_protocol[0].dhchap.idlist[31] = NVME_AUTH_DHGROUP_2048;
144	data->auth_protocol[0].dhchap.idlist[32] = NVME_AUTH_DHGROUP_3072;
145	data->auth_protocol[0].dhchap.idlist[33] = NVME_AUTH_DHGROUP_4096;
146	data->auth_protocol[0].dhchap.idlist[34] = NVME_AUTH_DHGROUP_6144;
147	data->auth_protocol[0].dhchap.idlist[35] = NVME_AUTH_DHGROUP_8192;
148
149	return size;
150}
151
152static int nvme_auth_process_dhchap_challenge(struct nvme_ctrl *ctrl,
153		struct nvme_dhchap_queue_context *chap)
154{
155	struct nvmf_auth_dhchap_challenge_data *data = chap->buf;
156	u16 dhvlen = le16_to_cpu(data->dhvlen);
157	size_t size = sizeof(*data) + data->hl + dhvlen;
158	const char *gid_name = nvme_auth_dhgroup_name(data->dhgid);
159	const char *hmac_name, *kpp_name;
160
161	if (size > CHAP_BUF_SIZE) {
162		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
163		return -EINVAL;
164	}
165
166	hmac_name = nvme_auth_hmac_name(data->hashid);
167	if (!hmac_name) {
168		dev_warn(ctrl->device,
169			 "qid %d: invalid HASH ID %d\n",
170			 chap->qid, data->hashid);
171		chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
172		return -EPROTO;
173	}
174
175	if (chap->hash_id == data->hashid && chap->shash_tfm &&
176	    !strcmp(crypto_shash_alg_name(chap->shash_tfm), hmac_name) &&
177	    crypto_shash_digestsize(chap->shash_tfm) == data->hl) {
178		dev_dbg(ctrl->device,
179			"qid %d: reuse existing hash %s\n",
180			chap->qid, hmac_name);
181		goto select_kpp;
182	}
183
184	/* Reset if hash cannot be reused */
185	if (chap->shash_tfm) {
186		crypto_free_shash(chap->shash_tfm);
187		chap->hash_id = 0;
188		chap->hash_len = 0;
189	}
190	chap->shash_tfm = crypto_alloc_shash(hmac_name, 0,
191					     CRYPTO_ALG_ALLOCATES_MEMORY);
192	if (IS_ERR(chap->shash_tfm)) {
193		dev_warn(ctrl->device,
194			 "qid %d: failed to allocate hash %s, error %ld\n",
195			 chap->qid, hmac_name, PTR_ERR(chap->shash_tfm));
196		chap->shash_tfm = NULL;
197		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
198		return -ENOMEM;
199	}
200
201	if (crypto_shash_digestsize(chap->shash_tfm) != data->hl) {
202		dev_warn(ctrl->device,
203			 "qid %d: invalid hash length %d\n",
204			 chap->qid, data->hl);
205		crypto_free_shash(chap->shash_tfm);
206		chap->shash_tfm = NULL;
207		chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
208		return -EPROTO;
209	}
210
211	chap->hash_id = data->hashid;
212	chap->hash_len = data->hl;
213	dev_dbg(ctrl->device, "qid %d: selected hash %s\n",
214		chap->qid, hmac_name);
215
216select_kpp:
217	kpp_name = nvme_auth_dhgroup_kpp(data->dhgid);
218	if (!kpp_name) {
219		dev_warn(ctrl->device,
220			 "qid %d: invalid DH group id %d\n",
221			 chap->qid, data->dhgid);
222		chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
223		/* Leave previous dh_tfm intact */
224		return -EPROTO;
225	}
226
227	if (chap->dhgroup_id == data->dhgid &&
228	    (data->dhgid == NVME_AUTH_DHGROUP_NULL || chap->dh_tfm)) {
229		dev_dbg(ctrl->device,
230			"qid %d: reuse existing DH group %s\n",
231			chap->qid, gid_name);
232		goto skip_kpp;
233	}
234
235	/* Reset dh_tfm if it can't be reused */
236	if (chap->dh_tfm) {
237		crypto_free_kpp(chap->dh_tfm);
238		chap->dh_tfm = NULL;
239	}
240
241	if (data->dhgid != NVME_AUTH_DHGROUP_NULL) {
242		if (dhvlen == 0) {
243			dev_warn(ctrl->device,
244				 "qid %d: empty DH value\n",
245				 chap->qid);
246			chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
247			return -EPROTO;
248		}
249
250		chap->dh_tfm = crypto_alloc_kpp(kpp_name, 0, 0);
251		if (IS_ERR(chap->dh_tfm)) {
252			int ret = PTR_ERR(chap->dh_tfm);
253
254			dev_warn(ctrl->device,
255				 "qid %d: error %d initializing DH group %s\n",
256				 chap->qid, ret, gid_name);
257			chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
258			chap->dh_tfm = NULL;
259			return ret;
260		}
261		dev_dbg(ctrl->device, "qid %d: selected DH group %s\n",
262			chap->qid, gid_name);
263	} else if (dhvlen != 0) {
264		dev_warn(ctrl->device,
265			 "qid %d: invalid DH value for NULL DH\n",
266			 chap->qid);
267		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
268		return -EPROTO;
269	}
270	chap->dhgroup_id = data->dhgid;
271
272skip_kpp:
273	chap->s1 = le32_to_cpu(data->seqnum);
274	memcpy(chap->c1, data->cval, chap->hash_len);
275	if (dhvlen) {
276		chap->ctrl_key = kmalloc(dhvlen, GFP_KERNEL);
277		if (!chap->ctrl_key) {
278			chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
279			return -ENOMEM;
280		}
281		chap->ctrl_key_len = dhvlen;
282		memcpy(chap->ctrl_key, data->cval + chap->hash_len,
283		       dhvlen);
284		dev_dbg(ctrl->device, "ctrl public key %*ph\n",
285			 (int)chap->ctrl_key_len, chap->ctrl_key);
286	}
287
288	return 0;
289}
290
291static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
292		struct nvme_dhchap_queue_context *chap)
293{
294	struct nvmf_auth_dhchap_reply_data *data = chap->buf;
295	size_t size = sizeof(*data);
296
297	size += 2 * chap->hash_len;
298
299	if (chap->host_key_len)
300		size += chap->host_key_len;
301
302	if (size > CHAP_BUF_SIZE) {
303		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
304		return -EINVAL;
305	}
306
307	memset(chap->buf, 0, size);
308	data->auth_type = NVME_AUTH_DHCHAP_MESSAGES;
309	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_REPLY;
310	data->t_id = cpu_to_le16(chap->transaction);
311	data->hl = chap->hash_len;
312	data->dhvlen = cpu_to_le16(chap->host_key_len);
313	memcpy(data->rval, chap->response, chap->hash_len);
314	if (ctrl->ctrl_key) {
315		chap->bi_directional = true;
316		get_random_bytes(chap->c2, chap->hash_len);
317		data->cvalid = 1;
318		memcpy(data->rval + chap->hash_len, chap->c2,
319		       chap->hash_len);
320		dev_dbg(ctrl->device, "%s: qid %d ctrl challenge %*ph\n",
321			__func__, chap->qid, (int)chap->hash_len, chap->c2);
322	} else {
323		memset(chap->c2, 0, chap->hash_len);
324	}
325	chap->s2 = nvme_auth_get_seqnum();
326	data->seqnum = cpu_to_le32(chap->s2);
327	if (chap->host_key_len) {
328		dev_dbg(ctrl->device, "%s: qid %d host public key %*ph\n",
329			__func__, chap->qid,
330			chap->host_key_len, chap->host_key);
331		memcpy(data->rval + 2 * chap->hash_len, chap->host_key,
332		       chap->host_key_len);
333	}
334
335	return size;
336}
337
338static int nvme_auth_process_dhchap_success1(struct nvme_ctrl *ctrl,
339		struct nvme_dhchap_queue_context *chap)
340{
341	struct nvmf_auth_dhchap_success1_data *data = chap->buf;
342	size_t size = sizeof(*data) + chap->hash_len;
343
344	if (size > CHAP_BUF_SIZE) {
345		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
346		return -EINVAL;
347	}
348
349	if (data->hl != chap->hash_len) {
350		dev_warn(ctrl->device,
351			 "qid %d: invalid hash length %u\n",
352			 chap->qid, data->hl);
353		chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
354		return -EPROTO;
355	}
356
357	/* Just print out information for the admin queue */
358	if (chap->qid == 0)
359		dev_info(ctrl->device,
360			 "qid 0: authenticated with hash %s dhgroup %s\n",
361			 nvme_auth_hmac_name(chap->hash_id),
362			 nvme_auth_dhgroup_name(chap->dhgroup_id));
363
364	if (!data->rvalid)
365		return 0;
366
367	/* Validate controller response */
368	if (memcmp(chap->response, data->rval, data->hl)) {
369		dev_dbg(ctrl->device, "%s: qid %d ctrl response %*ph\n",
370			__func__, chap->qid, (int)chap->hash_len, data->rval);
371		dev_dbg(ctrl->device, "%s: qid %d host response %*ph\n",
372			__func__, chap->qid, (int)chap->hash_len,
373			chap->response);
374		dev_warn(ctrl->device,
375			 "qid %d: controller authentication failed\n",
376			 chap->qid);
377		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
378		return -ECONNREFUSED;
379	}
380
381	/* Just print out information for the admin queue */
382	if (chap->qid == 0)
383		dev_info(ctrl->device,
384			 "qid 0: controller authenticated\n");
385	return 0;
386}
387
388static int nvme_auth_set_dhchap_success2_data(struct nvme_ctrl *ctrl,
389		struct nvme_dhchap_queue_context *chap)
390{
391	struct nvmf_auth_dhchap_success2_data *data = chap->buf;
392	size_t size = sizeof(*data);
393
394	memset(chap->buf, 0, size);
395	data->auth_type = NVME_AUTH_DHCHAP_MESSAGES;
396	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_SUCCESS2;
397	data->t_id = cpu_to_le16(chap->transaction);
398
399	return size;
400}
401
402static int nvme_auth_set_dhchap_failure2_data(struct nvme_ctrl *ctrl,
403		struct nvme_dhchap_queue_context *chap)
404{
405	struct nvmf_auth_dhchap_failure_data *data = chap->buf;
406	size_t size = sizeof(*data);
407
408	memset(chap->buf, 0, size);
409	data->auth_type = NVME_AUTH_COMMON_MESSAGES;
410	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_FAILURE2;
411	data->t_id = cpu_to_le16(chap->transaction);
412	data->rescode = NVME_AUTH_DHCHAP_FAILURE_REASON_FAILED;
413	data->rescode_exp = chap->status;
414
415	return size;
416}
417
418static int nvme_auth_dhchap_setup_host_response(struct nvme_ctrl *ctrl,
419		struct nvme_dhchap_queue_context *chap)
420{
421	SHASH_DESC_ON_STACK(shash, chap->shash_tfm);
422	u8 buf[4], *challenge = chap->c1;
423	int ret;
424
425	dev_dbg(ctrl->device, "%s: qid %d host response seq %u transaction %d\n",
426		__func__, chap->qid, chap->s1, chap->transaction);
427
428	if (!chap->transformed_key) {
429		chap->transformed_key = nvme_auth_transform_key(ctrl->host_key,
430						ctrl->opts->host->nqn);
431		if (IS_ERR(chap->transformed_key)) {
432			ret = PTR_ERR(chap->transformed_key);
433			chap->transformed_key = NULL;
434			return ret;
435		}
436	} else {
437		dev_dbg(ctrl->device, "%s: qid %d re-using host response\n",
438			__func__, chap->qid);
439	}
440
441	ret = crypto_shash_setkey(chap->shash_tfm,
442			chap->transformed_key->key, chap->transformed_key->len);
443	if (ret) {
444		dev_warn(ctrl->device, "qid %d: failed to set key, error %d\n",
445			 chap->qid, ret);
446		goto out;
447	}
448
449	if (chap->dh_tfm) {
450		challenge = kmalloc(chap->hash_len, GFP_KERNEL);
451		if (!challenge) {
452			ret = -ENOMEM;
453			goto out;
454		}
455		ret = nvme_auth_augmented_challenge(chap->hash_id,
456						    chap->sess_key,
457						    chap->sess_key_len,
458						    chap->c1, challenge,
459						    chap->hash_len);
460		if (ret)
461			goto out;
462	}
463
464	shash->tfm = chap->shash_tfm;
465	ret = crypto_shash_init(shash);
466	if (ret)
467		goto out;
468	ret = crypto_shash_update(shash, challenge, chap->hash_len);
469	if (ret)
470		goto out;
471	put_unaligned_le32(chap->s1, buf);
472	ret = crypto_shash_update(shash, buf, 4);
473	if (ret)
474		goto out;
475	put_unaligned_le16(chap->transaction, buf);
476	ret = crypto_shash_update(shash, buf, 2);
477	if (ret)
478		goto out;
479	memset(buf, 0, sizeof(buf));
480	ret = crypto_shash_update(shash, buf, 1);
481	if (ret)
482		goto out;
483	ret = crypto_shash_update(shash, "HostHost", 8);
484	if (ret)
485		goto out;
486	ret = crypto_shash_update(shash, ctrl->opts->host->nqn,
487				  strlen(ctrl->opts->host->nqn));
488	if (ret)
489		goto out;
490	ret = crypto_shash_update(shash, buf, 1);
491	if (ret)
492		goto out;
493	ret = crypto_shash_update(shash, ctrl->opts->subsysnqn,
494			    strlen(ctrl->opts->subsysnqn));
495	if (ret)
496		goto out;
497	ret = crypto_shash_final(shash, chap->response);
498out:
499	if (challenge != chap->c1)
500		kfree(challenge);
501	return ret;
502}
503
504static int nvme_auth_dhchap_setup_ctrl_response(struct nvme_ctrl *ctrl,
505		struct nvme_dhchap_queue_context *chap)
506{
507	SHASH_DESC_ON_STACK(shash, chap->shash_tfm);
508	struct nvme_dhchap_key *transformed_key;
509	u8 buf[4], *challenge = chap->c2;
510	int ret;
511
512	transformed_key = nvme_auth_transform_key(ctrl->ctrl_key,
513				ctrl->opts->subsysnqn);
514	if (IS_ERR(transformed_key)) {
515		ret = PTR_ERR(transformed_key);
516		return ret;
517	}
518
519	ret = crypto_shash_setkey(chap->shash_tfm,
520			transformed_key->key, transformed_key->len);
521	if (ret) {
522		dev_warn(ctrl->device, "qid %d: failed to set key, error %d\n",
523			 chap->qid, ret);
524		goto out;
525	}
526
527	if (chap->dh_tfm) {
528		challenge = kmalloc(chap->hash_len, GFP_KERNEL);
529		if (!challenge) {
530			ret = -ENOMEM;
531			goto out;
532		}
533		ret = nvme_auth_augmented_challenge(chap->hash_id,
534						    chap->sess_key,
535						    chap->sess_key_len,
536						    chap->c2, challenge,
537						    chap->hash_len);
538		if (ret)
539			goto out;
540	}
541	dev_dbg(ctrl->device, "%s: qid %d ctrl response seq %u transaction %d\n",
542		__func__, chap->qid, chap->s2, chap->transaction);
543	dev_dbg(ctrl->device, "%s: qid %d challenge %*ph\n",
544		__func__, chap->qid, (int)chap->hash_len, challenge);
545	dev_dbg(ctrl->device, "%s: qid %d subsysnqn %s\n",
546		__func__, chap->qid, ctrl->opts->subsysnqn);
547	dev_dbg(ctrl->device, "%s: qid %d hostnqn %s\n",
548		__func__, chap->qid, ctrl->opts->host->nqn);
549	shash->tfm = chap->shash_tfm;
550	ret = crypto_shash_init(shash);
551	if (ret)
552		goto out;
553	ret = crypto_shash_update(shash, challenge, chap->hash_len);
554	if (ret)
555		goto out;
556	put_unaligned_le32(chap->s2, buf);
557	ret = crypto_shash_update(shash, buf, 4);
558	if (ret)
559		goto out;
560	put_unaligned_le16(chap->transaction, buf);
561	ret = crypto_shash_update(shash, buf, 2);
562	if (ret)
563		goto out;
564	memset(buf, 0, 4);
565	ret = crypto_shash_update(shash, buf, 1);
566	if (ret)
567		goto out;
568	ret = crypto_shash_update(shash, "Controller", 10);
569	if (ret)
570		goto out;
571	ret = crypto_shash_update(shash, ctrl->opts->subsysnqn,
572				  strlen(ctrl->opts->subsysnqn));
573	if (ret)
574		goto out;
575	ret = crypto_shash_update(shash, buf, 1);
576	if (ret)
577		goto out;
578	ret = crypto_shash_update(shash, ctrl->opts->host->nqn,
579				  strlen(ctrl->opts->host->nqn));
580	if (ret)
581		goto out;
582	ret = crypto_shash_final(shash, chap->response);
583out:
584	if (challenge != chap->c2)
585		kfree(challenge);
586	nvme_auth_free_key(transformed_key);
587	return ret;
588}
589
590static int nvme_auth_dhchap_exponential(struct nvme_ctrl *ctrl,
591		struct nvme_dhchap_queue_context *chap)
592{
593	int ret;
594
595	if (chap->host_key && chap->host_key_len) {
596		dev_dbg(ctrl->device,
597			"qid %d: reusing host key\n", chap->qid);
598		goto gen_sesskey;
599	}
600	ret = nvme_auth_gen_privkey(chap->dh_tfm, chap->dhgroup_id);
601	if (ret < 0) {
602		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
603		return ret;
604	}
605
606	chap->host_key_len = crypto_kpp_maxsize(chap->dh_tfm);
607
608	chap->host_key = kzalloc(chap->host_key_len, GFP_KERNEL);
609	if (!chap->host_key) {
610		chap->host_key_len = 0;
611		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
612		return -ENOMEM;
613	}
614	ret = nvme_auth_gen_pubkey(chap->dh_tfm,
615				   chap->host_key, chap->host_key_len);
616	if (ret) {
617		dev_dbg(ctrl->device,
618			"failed to generate public key, error %d\n", ret);
619		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
620		return ret;
621	}
622
623gen_sesskey:
624	chap->sess_key_len = chap->host_key_len;
625	chap->sess_key = kmalloc(chap->sess_key_len, GFP_KERNEL);
626	if (!chap->sess_key) {
627		chap->sess_key_len = 0;
628		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
629		return -ENOMEM;
630	}
631
632	ret = nvme_auth_gen_shared_secret(chap->dh_tfm,
633					  chap->ctrl_key, chap->ctrl_key_len,
634					  chap->sess_key, chap->sess_key_len);
635	if (ret) {
636		dev_dbg(ctrl->device,
637			"failed to generate shared secret, error %d\n", ret);
638		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
639		return ret;
640	}
641	dev_dbg(ctrl->device, "shared secret %*ph\n",
642		(int)chap->sess_key_len, chap->sess_key);
643	return 0;
644}
645
646static void nvme_auth_reset_dhchap(struct nvme_dhchap_queue_context *chap)
647{
648	nvme_auth_free_key(chap->transformed_key);
649	chap->transformed_key = NULL;
650	kfree_sensitive(chap->host_key);
651	chap->host_key = NULL;
652	chap->host_key_len = 0;
653	kfree_sensitive(chap->ctrl_key);
654	chap->ctrl_key = NULL;
655	chap->ctrl_key_len = 0;
656	kfree_sensitive(chap->sess_key);
657	chap->sess_key = NULL;
658	chap->sess_key_len = 0;
659	chap->status = 0;
660	chap->error = 0;
661	chap->s1 = 0;
662	chap->s2 = 0;
663	chap->bi_directional = false;
664	chap->transaction = 0;
665	memset(chap->c1, 0, sizeof(chap->c1));
666	memset(chap->c2, 0, sizeof(chap->c2));
667	mempool_free(chap->buf, nvme_chap_buf_pool);
668	chap->buf = NULL;
669}
670
671static void nvme_auth_free_dhchap(struct nvme_dhchap_queue_context *chap)
672{
673	nvme_auth_reset_dhchap(chap);
674	if (chap->shash_tfm)
675		crypto_free_shash(chap->shash_tfm);
676	if (chap->dh_tfm)
677		crypto_free_kpp(chap->dh_tfm);
678}
679
680static void nvme_queue_auth_work(struct work_struct *work)
681{
682	struct nvme_dhchap_queue_context *chap =
683		container_of(work, struct nvme_dhchap_queue_context, auth_work);
684	struct nvme_ctrl *ctrl = chap->ctrl;
685	size_t tl;
686	int ret = 0;
687
688	/*
689	 * Allocate a large enough buffer for the entire negotiation:
690	 * 4k is enough to ffdhe8192.
691	 */
692	chap->buf = mempool_alloc(nvme_chap_buf_pool, GFP_KERNEL);
693	if (!chap->buf) {
694		chap->error = -ENOMEM;
695		return;
696	}
697
698	chap->transaction = ctrl->transaction++;
699
700	/* DH-HMAC-CHAP Step 1: send negotiate */
701	dev_dbg(ctrl->device, "%s: qid %d send negotiate\n",
702		__func__, chap->qid);
703	ret = nvme_auth_set_dhchap_negotiate_data(ctrl, chap);
704	if (ret < 0) {
705		chap->error = ret;
706		return;
707	}
708	tl = ret;
709	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
710	if (ret) {
711		chap->error = ret;
712		return;
713	}
714
715	/* DH-HMAC-CHAP Step 2: receive challenge */
716	dev_dbg(ctrl->device, "%s: qid %d receive challenge\n",
717		__func__, chap->qid);
718
719	memset(chap->buf, 0, CHAP_BUF_SIZE);
720	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, CHAP_BUF_SIZE,
721			       false);
722	if (ret) {
723		dev_warn(ctrl->device,
724			 "qid %d failed to receive challenge, %s %d\n",
725			 chap->qid, ret < 0 ? "error" : "nvme status", ret);
726		chap->error = ret;
727		return;
728	}
729	ret = nvme_auth_receive_validate(ctrl, chap->qid, chap->buf, chap->transaction,
730					 NVME_AUTH_DHCHAP_MESSAGE_CHALLENGE);
731	if (ret) {
732		chap->status = ret;
733		chap->error = -ECONNREFUSED;
734		return;
735	}
736
737	ret = nvme_auth_process_dhchap_challenge(ctrl, chap);
738	if (ret) {
739		/* Invalid challenge parameters */
740		chap->error = ret;
741		goto fail2;
742	}
743
744	if (chap->ctrl_key_len) {
745		dev_dbg(ctrl->device,
746			"%s: qid %d DH exponential\n",
747			__func__, chap->qid);
748		ret = nvme_auth_dhchap_exponential(ctrl, chap);
749		if (ret) {
750			chap->error = ret;
751			goto fail2;
752		}
753	}
754
755	dev_dbg(ctrl->device, "%s: qid %d host response\n",
756		__func__, chap->qid);
757	mutex_lock(&ctrl->dhchap_auth_mutex);
758	ret = nvme_auth_dhchap_setup_host_response(ctrl, chap);
759	mutex_unlock(&ctrl->dhchap_auth_mutex);
760	if (ret) {
761		chap->error = ret;
762		goto fail2;
763	}
764
765	/* DH-HMAC-CHAP Step 3: send reply */
766	dev_dbg(ctrl->device, "%s: qid %d send reply\n",
767		__func__, chap->qid);
768	ret = nvme_auth_set_dhchap_reply_data(ctrl, chap);
769	if (ret < 0) {
770		chap->error = ret;
771		goto fail2;
772	}
773
774	tl = ret;
775	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
776	if (ret) {
777		chap->error = ret;
778		goto fail2;
779	}
780
781	/* DH-HMAC-CHAP Step 4: receive success1 */
782	dev_dbg(ctrl->device, "%s: qid %d receive success1\n",
783		__func__, chap->qid);
784
785	memset(chap->buf, 0, CHAP_BUF_SIZE);
786	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, CHAP_BUF_SIZE,
787			       false);
788	if (ret) {
789		dev_warn(ctrl->device,
790			 "qid %d failed to receive success1, %s %d\n",
791			 chap->qid, ret < 0 ? "error" : "nvme status", ret);
792		chap->error = ret;
793		return;
794	}
795	ret = nvme_auth_receive_validate(ctrl, chap->qid,
796					 chap->buf, chap->transaction,
797					 NVME_AUTH_DHCHAP_MESSAGE_SUCCESS1);
798	if (ret) {
799		chap->status = ret;
800		chap->error = -ECONNREFUSED;
801		return;
802	}
803
804	mutex_lock(&ctrl->dhchap_auth_mutex);
805	if (ctrl->ctrl_key) {
806		dev_dbg(ctrl->device,
807			"%s: qid %d controller response\n",
808			__func__, chap->qid);
809		ret = nvme_auth_dhchap_setup_ctrl_response(ctrl, chap);
810		if (ret) {
811			mutex_unlock(&ctrl->dhchap_auth_mutex);
812			chap->error = ret;
813			goto fail2;
814		}
815	}
816	mutex_unlock(&ctrl->dhchap_auth_mutex);
817
818	ret = nvme_auth_process_dhchap_success1(ctrl, chap);
819	if (ret) {
820		/* Controller authentication failed */
821		chap->error = -ECONNREFUSED;
822		goto fail2;
823	}
824
825	if (chap->bi_directional) {
826		/* DH-HMAC-CHAP Step 5: send success2 */
827		dev_dbg(ctrl->device, "%s: qid %d send success2\n",
828			__func__, chap->qid);
829		tl = nvme_auth_set_dhchap_success2_data(ctrl, chap);
830		ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
831		if (ret)
832			chap->error = ret;
833	}
834	if (!ret) {
835		chap->error = 0;
836		return;
837	}
838
839fail2:
840	if (chap->status == 0)
841		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
842	dev_dbg(ctrl->device, "%s: qid %d send failure2, status %x\n",
843		__func__, chap->qid, chap->status);
844	tl = nvme_auth_set_dhchap_failure2_data(ctrl, chap);
845	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
846	/*
847	 * only update error if send failure2 failed and no other
848	 * error had been set during authentication.
849	 */
850	if (ret && !chap->error)
851		chap->error = ret;
852}
853
854int nvme_auth_negotiate(struct nvme_ctrl *ctrl, int qid)
855{
856	struct nvme_dhchap_queue_context *chap;
857
858	if (!ctrl->host_key) {
859		dev_warn(ctrl->device, "qid %d: no key\n", qid);
860		return -ENOKEY;
861	}
862
863	if (ctrl->opts->dhchap_ctrl_secret && !ctrl->ctrl_key) {
864		dev_warn(ctrl->device, "qid %d: invalid ctrl key\n", qid);
865		return -ENOKEY;
866	}
867
868	chap = &ctrl->dhchap_ctxs[qid];
869	cancel_work_sync(&chap->auth_work);
870	queue_work(nvme_auth_wq, &chap->auth_work);
871	return 0;
872}
873EXPORT_SYMBOL_GPL(nvme_auth_negotiate);
874
875int nvme_auth_wait(struct nvme_ctrl *ctrl, int qid)
876{
877	struct nvme_dhchap_queue_context *chap;
878	int ret;
879
880	chap = &ctrl->dhchap_ctxs[qid];
881	flush_work(&chap->auth_work);
882	ret = chap->error;
883	/* clear sensitive info */
884	nvme_auth_reset_dhchap(chap);
885	return ret;
886}
887EXPORT_SYMBOL_GPL(nvme_auth_wait);
888
889static void nvme_ctrl_auth_work(struct work_struct *work)
890{
891	struct nvme_ctrl *ctrl =
892		container_of(work, struct nvme_ctrl, dhchap_auth_work);
893	int ret, q;
894
895	/*
896	 * If the ctrl is no connected, bail as reconnect will handle
897	 * authentication.
898	 */
899	if (nvme_ctrl_state(ctrl) != NVME_CTRL_LIVE)
900		return;
901
902	/* Authenticate admin queue first */
903	ret = nvme_auth_negotiate(ctrl, 0);
904	if (ret) {
905		dev_warn(ctrl->device,
906			 "qid 0: error %d setting up authentication\n", ret);
907		return;
908	}
909	ret = nvme_auth_wait(ctrl, 0);
910	if (ret) {
911		dev_warn(ctrl->device,
912			 "qid 0: authentication failed\n");
913		return;
914	}
915
916	for (q = 1; q < ctrl->queue_count; q++) {
917		ret = nvme_auth_negotiate(ctrl, q);
918		if (ret) {
919			dev_warn(ctrl->device,
920				 "qid %d: error %d setting up authentication\n",
921				 q, ret);
922			break;
923		}
924	}
925
926	/*
927	 * Failure is a soft-state; credentials remain valid until
928	 * the controller terminates the connection.
929	 */
930	for (q = 1; q < ctrl->queue_count; q++) {
931		ret = nvme_auth_wait(ctrl, q);
932		if (ret)
933			dev_warn(ctrl->device,
934				 "qid %d: authentication failed\n", q);
935	}
936}
937
938int nvme_auth_init_ctrl(struct nvme_ctrl *ctrl)
939{
940	struct nvme_dhchap_queue_context *chap;
941	int i, ret;
942
943	mutex_init(&ctrl->dhchap_auth_mutex);
944	INIT_WORK(&ctrl->dhchap_auth_work, nvme_ctrl_auth_work);
945	if (!ctrl->opts)
946		return 0;
947	ret = nvme_auth_generate_key(ctrl->opts->dhchap_secret,
948			&ctrl->host_key);
949	if (ret)
950		return ret;
951	ret = nvme_auth_generate_key(ctrl->opts->dhchap_ctrl_secret,
952			&ctrl->ctrl_key);
953	if (ret)
954		goto err_free_dhchap_secret;
955
956	if (!ctrl->opts->dhchap_secret && !ctrl->opts->dhchap_ctrl_secret)
957		return 0;
958
959	ctrl->dhchap_ctxs = kvcalloc(ctrl_max_dhchaps(ctrl),
960				sizeof(*chap), GFP_KERNEL);
961	if (!ctrl->dhchap_ctxs) {
962		ret = -ENOMEM;
963		goto err_free_dhchap_ctrl_secret;
964	}
965
966	for (i = 0; i < ctrl_max_dhchaps(ctrl); i++) {
967		chap = &ctrl->dhchap_ctxs[i];
968		chap->qid = i;
969		chap->ctrl = ctrl;
970		INIT_WORK(&chap->auth_work, nvme_queue_auth_work);
971	}
972
973	return 0;
974err_free_dhchap_ctrl_secret:
975	nvme_auth_free_key(ctrl->ctrl_key);
976	ctrl->ctrl_key = NULL;
977err_free_dhchap_secret:
978	nvme_auth_free_key(ctrl->host_key);
979	ctrl->host_key = NULL;
980	return ret;
981}
982EXPORT_SYMBOL_GPL(nvme_auth_init_ctrl);
983
984void nvme_auth_stop(struct nvme_ctrl *ctrl)
985{
986	cancel_work_sync(&ctrl->dhchap_auth_work);
987}
988EXPORT_SYMBOL_GPL(nvme_auth_stop);
989
990void nvme_auth_free(struct nvme_ctrl *ctrl)
991{
992	int i;
993
994	if (ctrl->dhchap_ctxs) {
995		for (i = 0; i < ctrl_max_dhchaps(ctrl); i++)
996			nvme_auth_free_dhchap(&ctrl->dhchap_ctxs[i]);
997		kfree(ctrl->dhchap_ctxs);
998	}
999	if (ctrl->host_key) {
1000		nvme_auth_free_key(ctrl->host_key);
1001		ctrl->host_key = NULL;
1002	}
1003	if (ctrl->ctrl_key) {
1004		nvme_auth_free_key(ctrl->ctrl_key);
1005		ctrl->ctrl_key = NULL;
1006	}
1007}
1008EXPORT_SYMBOL_GPL(nvme_auth_free);
1009
1010int __init nvme_init_auth(void)
1011{
1012	nvme_auth_wq = alloc_workqueue("nvme-auth-wq",
1013			       WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, 0);
1014	if (!nvme_auth_wq)
1015		return -ENOMEM;
1016
1017	nvme_chap_buf_cache = kmem_cache_create("nvme-chap-buf-cache",
1018				CHAP_BUF_SIZE, 0, SLAB_HWCACHE_ALIGN, NULL);
1019	if (!nvme_chap_buf_cache)
1020		goto err_destroy_workqueue;
1021
1022	nvme_chap_buf_pool = mempool_create(16, mempool_alloc_slab,
1023			mempool_free_slab, nvme_chap_buf_cache);
1024	if (!nvme_chap_buf_pool)
1025		goto err_destroy_chap_buf_cache;
1026
1027	return 0;
1028err_destroy_chap_buf_cache:
1029	kmem_cache_destroy(nvme_chap_buf_cache);
1030err_destroy_workqueue:
1031	destroy_workqueue(nvme_auth_wq);
1032	return -ENOMEM;
1033}
1034
1035void __exit nvme_exit_auth(void)
1036{
1037	mempool_destroy(nvme_chap_buf_pool);
1038	kmem_cache_destroy(nvme_chap_buf_cache);
1039	destroy_workqueue(nvme_auth_wq);
1040}
1041