xref: /linux/drivers/nvme/host/auth.c (revision e80a48bade619ec5a92230b3d4ae84bfc2746822)
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
17 static struct kmem_cache *nvme_chap_buf_cache;
18 static mempool_t *nvme_chap_buf_pool;
19 
20 struct 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 	void *buf;
27 	int qid;
28 	int error;
29 	u32 s1;
30 	u32 s2;
31 	u16 transaction;
32 	u8 status;
33 	u8 hash_id;
34 	size_t hash_len;
35 	u8 dhgroup_id;
36 	u8 c1[64];
37 	u8 c2[64];
38 	u8 response[64];
39 	u8 *host_response;
40 	u8 *ctrl_key;
41 	int ctrl_key_len;
42 	u8 *host_key;
43 	int host_key_len;
44 	u8 *sess_key;
45 	int sess_key_len;
46 };
47 
48 #define nvme_auth_flags_from_qid(qid) \
49 	(qid == 0) ? 0 : BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED
50 #define nvme_auth_queue_from_qid(ctrl, qid) \
51 	(qid == 0) ? (ctrl)->fabrics_q : (ctrl)->connect_q
52 
53 static inline int ctrl_max_dhchaps(struct nvme_ctrl *ctrl)
54 {
55 	return ctrl->opts->nr_io_queues + ctrl->opts->nr_write_queues +
56 			ctrl->opts->nr_poll_queues + 1;
57 }
58 
59 static int nvme_auth_submit(struct nvme_ctrl *ctrl, int qid,
60 			    void *data, size_t data_len, bool auth_send)
61 {
62 	struct nvme_command cmd = {};
63 	blk_mq_req_flags_t flags = nvme_auth_flags_from_qid(qid);
64 	struct request_queue *q = nvme_auth_queue_from_qid(ctrl, qid);
65 	int ret;
66 
67 	cmd.auth_common.opcode = nvme_fabrics_command;
68 	cmd.auth_common.secp = NVME_AUTH_DHCHAP_PROTOCOL_IDENTIFIER;
69 	cmd.auth_common.spsp0 = 0x01;
70 	cmd.auth_common.spsp1 = 0x01;
71 	if (auth_send) {
72 		cmd.auth_send.fctype = nvme_fabrics_type_auth_send;
73 		cmd.auth_send.tl = cpu_to_le32(data_len);
74 	} else {
75 		cmd.auth_receive.fctype = nvme_fabrics_type_auth_receive;
76 		cmd.auth_receive.al = cpu_to_le32(data_len);
77 	}
78 
79 	ret = __nvme_submit_sync_cmd(q, &cmd, NULL, data, data_len,
80 				     qid == 0 ? NVME_QID_ANY : qid,
81 				     0, flags);
82 	if (ret > 0)
83 		dev_warn(ctrl->device,
84 			"qid %d auth_send failed with status %d\n", qid, ret);
85 	else if (ret < 0)
86 		dev_err(ctrl->device,
87 			"qid %d auth_send failed with error %d\n", qid, ret);
88 	return ret;
89 }
90 
91 static int nvme_auth_receive_validate(struct nvme_ctrl *ctrl, int qid,
92 		struct nvmf_auth_dhchap_failure_data *data,
93 		u16 transaction, u8 expected_msg)
94 {
95 	dev_dbg(ctrl->device, "%s: qid %d auth_type %d auth_id %x\n",
96 		__func__, qid, data->auth_type, data->auth_id);
97 
98 	if (data->auth_type == NVME_AUTH_COMMON_MESSAGES &&
99 	    data->auth_id == NVME_AUTH_DHCHAP_MESSAGE_FAILURE1) {
100 		return data->rescode_exp;
101 	}
102 	if (data->auth_type != NVME_AUTH_DHCHAP_MESSAGES ||
103 	    data->auth_id != expected_msg) {
104 		dev_warn(ctrl->device,
105 			 "qid %d invalid message %02x/%02x\n",
106 			 qid, data->auth_type, data->auth_id);
107 		return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_MESSAGE;
108 	}
109 	if (le16_to_cpu(data->t_id) != transaction) {
110 		dev_warn(ctrl->device,
111 			 "qid %d invalid transaction ID %d\n",
112 			 qid, le16_to_cpu(data->t_id));
113 		return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_MESSAGE;
114 	}
115 	return 0;
116 }
117 
118 static int nvme_auth_set_dhchap_negotiate_data(struct nvme_ctrl *ctrl,
119 		struct nvme_dhchap_queue_context *chap)
120 {
121 	struct nvmf_auth_dhchap_negotiate_data *data = chap->buf;
122 	size_t size = sizeof(*data) + sizeof(union nvmf_auth_protocol);
123 
124 	if (size > CHAP_BUF_SIZE) {
125 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
126 		return -EINVAL;
127 	}
128 	memset((u8 *)chap->buf, 0, size);
129 	data->auth_type = NVME_AUTH_COMMON_MESSAGES;
130 	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_NEGOTIATE;
131 	data->t_id = cpu_to_le16(chap->transaction);
132 	data->sc_c = 0; /* No secure channel concatenation */
133 	data->napd = 1;
134 	data->auth_protocol[0].dhchap.authid = NVME_AUTH_DHCHAP_AUTH_ID;
135 	data->auth_protocol[0].dhchap.halen = 3;
136 	data->auth_protocol[0].dhchap.dhlen = 6;
137 	data->auth_protocol[0].dhchap.idlist[0] = NVME_AUTH_HASH_SHA256;
138 	data->auth_protocol[0].dhchap.idlist[1] = NVME_AUTH_HASH_SHA384;
139 	data->auth_protocol[0].dhchap.idlist[2] = NVME_AUTH_HASH_SHA512;
140 	data->auth_protocol[0].dhchap.idlist[30] = NVME_AUTH_DHGROUP_NULL;
141 	data->auth_protocol[0].dhchap.idlist[31] = NVME_AUTH_DHGROUP_2048;
142 	data->auth_protocol[0].dhchap.idlist[32] = NVME_AUTH_DHGROUP_3072;
143 	data->auth_protocol[0].dhchap.idlist[33] = NVME_AUTH_DHGROUP_4096;
144 	data->auth_protocol[0].dhchap.idlist[34] = NVME_AUTH_DHGROUP_6144;
145 	data->auth_protocol[0].dhchap.idlist[35] = NVME_AUTH_DHGROUP_8192;
146 
147 	return size;
148 }
149 
150 static int nvme_auth_process_dhchap_challenge(struct nvme_ctrl *ctrl,
151 		struct nvme_dhchap_queue_context *chap)
152 {
153 	struct nvmf_auth_dhchap_challenge_data *data = chap->buf;
154 	u16 dhvlen = le16_to_cpu(data->dhvlen);
155 	size_t size = sizeof(*data) + data->hl + dhvlen;
156 	const char *gid_name = nvme_auth_dhgroup_name(data->dhgid);
157 	const char *hmac_name, *kpp_name;
158 
159 	if (size > CHAP_BUF_SIZE) {
160 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
161 		return NVME_SC_INVALID_FIELD;
162 	}
163 
164 	hmac_name = nvme_auth_hmac_name(data->hashid);
165 	if (!hmac_name) {
166 		dev_warn(ctrl->device,
167 			 "qid %d: invalid HASH ID %d\n",
168 			 chap->qid, data->hashid);
169 		chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
170 		return NVME_SC_INVALID_FIELD;
171 	}
172 
173 	if (chap->hash_id == data->hashid && chap->shash_tfm &&
174 	    !strcmp(crypto_shash_alg_name(chap->shash_tfm), hmac_name) &&
175 	    crypto_shash_digestsize(chap->shash_tfm) == data->hl) {
176 		dev_dbg(ctrl->device,
177 			"qid %d: reuse existing hash %s\n",
178 			chap->qid, hmac_name);
179 		goto select_kpp;
180 	}
181 
182 	/* Reset if hash cannot be reused */
183 	if (chap->shash_tfm) {
184 		crypto_free_shash(chap->shash_tfm);
185 		chap->hash_id = 0;
186 		chap->hash_len = 0;
187 	}
188 	chap->shash_tfm = crypto_alloc_shash(hmac_name, 0,
189 					     CRYPTO_ALG_ALLOCATES_MEMORY);
190 	if (IS_ERR(chap->shash_tfm)) {
191 		dev_warn(ctrl->device,
192 			 "qid %d: failed to allocate hash %s, error %ld\n",
193 			 chap->qid, hmac_name, PTR_ERR(chap->shash_tfm));
194 		chap->shash_tfm = NULL;
195 		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
196 		return NVME_SC_AUTH_REQUIRED;
197 	}
198 
199 	if (crypto_shash_digestsize(chap->shash_tfm) != data->hl) {
200 		dev_warn(ctrl->device,
201 			 "qid %d: invalid hash length %d\n",
202 			 chap->qid, data->hl);
203 		crypto_free_shash(chap->shash_tfm);
204 		chap->shash_tfm = NULL;
205 		chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
206 		return NVME_SC_AUTH_REQUIRED;
207 	}
208 
209 	chap->hash_id = data->hashid;
210 	chap->hash_len = data->hl;
211 	dev_dbg(ctrl->device, "qid %d: selected hash %s\n",
212 		chap->qid, hmac_name);
213 
214 select_kpp:
215 	kpp_name = nvme_auth_dhgroup_kpp(data->dhgid);
216 	if (!kpp_name) {
217 		dev_warn(ctrl->device,
218 			 "qid %d: invalid DH group id %d\n",
219 			 chap->qid, data->dhgid);
220 		chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
221 		/* Leave previous dh_tfm intact */
222 		return NVME_SC_AUTH_REQUIRED;
223 	}
224 
225 	if (chap->dhgroup_id == data->dhgid &&
226 	    (data->dhgid == NVME_AUTH_DHGROUP_NULL || chap->dh_tfm)) {
227 		dev_dbg(ctrl->device,
228 			"qid %d: reuse existing DH group %s\n",
229 			chap->qid, gid_name);
230 		goto skip_kpp;
231 	}
232 
233 	/* Reset dh_tfm if it can't be reused */
234 	if (chap->dh_tfm) {
235 		crypto_free_kpp(chap->dh_tfm);
236 		chap->dh_tfm = NULL;
237 	}
238 
239 	if (data->dhgid != NVME_AUTH_DHGROUP_NULL) {
240 		if (dhvlen == 0) {
241 			dev_warn(ctrl->device,
242 				 "qid %d: empty DH value\n",
243 				 chap->qid);
244 			chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
245 			return NVME_SC_INVALID_FIELD;
246 		}
247 
248 		chap->dh_tfm = crypto_alloc_kpp(kpp_name, 0, 0);
249 		if (IS_ERR(chap->dh_tfm)) {
250 			int ret = PTR_ERR(chap->dh_tfm);
251 
252 			dev_warn(ctrl->device,
253 				 "qid %d: error %d initializing DH group %s\n",
254 				 chap->qid, ret, gid_name);
255 			chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
256 			chap->dh_tfm = NULL;
257 			return NVME_SC_AUTH_REQUIRED;
258 		}
259 		dev_dbg(ctrl->device, "qid %d: selected DH group %s\n",
260 			chap->qid, gid_name);
261 	} else if (dhvlen != 0) {
262 		dev_warn(ctrl->device,
263 			 "qid %d: invalid DH value for NULL DH\n",
264 			 chap->qid);
265 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
266 		return NVME_SC_INVALID_FIELD;
267 	}
268 	chap->dhgroup_id = data->dhgid;
269 
270 skip_kpp:
271 	chap->s1 = le32_to_cpu(data->seqnum);
272 	memcpy(chap->c1, data->cval, chap->hash_len);
273 	if (dhvlen) {
274 		chap->ctrl_key = kmalloc(dhvlen, GFP_KERNEL);
275 		if (!chap->ctrl_key) {
276 			chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
277 			return NVME_SC_AUTH_REQUIRED;
278 		}
279 		chap->ctrl_key_len = dhvlen;
280 		memcpy(chap->ctrl_key, data->cval + chap->hash_len,
281 		       dhvlen);
282 		dev_dbg(ctrl->device, "ctrl public key %*ph\n",
283 			 (int)chap->ctrl_key_len, chap->ctrl_key);
284 	}
285 
286 	return 0;
287 }
288 
289 static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
290 		struct nvme_dhchap_queue_context *chap)
291 {
292 	struct nvmf_auth_dhchap_reply_data *data = chap->buf;
293 	size_t size = sizeof(*data);
294 
295 	size += 2 * chap->hash_len;
296 
297 	if (chap->host_key_len)
298 		size += chap->host_key_len;
299 
300 	if (size > CHAP_BUF_SIZE) {
301 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
302 		return -EINVAL;
303 	}
304 
305 	memset(chap->buf, 0, size);
306 	data->auth_type = NVME_AUTH_DHCHAP_MESSAGES;
307 	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_REPLY;
308 	data->t_id = cpu_to_le16(chap->transaction);
309 	data->hl = chap->hash_len;
310 	data->dhvlen = cpu_to_le16(chap->host_key_len);
311 	memcpy(data->rval, chap->response, chap->hash_len);
312 	if (ctrl->ctrl_key) {
313 		get_random_bytes(chap->c2, chap->hash_len);
314 		data->cvalid = 1;
315 		chap->s2 = nvme_auth_get_seqnum();
316 		memcpy(data->rval + chap->hash_len, chap->c2,
317 		       chap->hash_len);
318 		dev_dbg(ctrl->device, "%s: qid %d ctrl challenge %*ph\n",
319 			__func__, chap->qid, (int)chap->hash_len, chap->c2);
320 	} else {
321 		memset(chap->c2, 0, chap->hash_len);
322 		chap->s2 = 0;
323 	}
324 	data->seqnum = cpu_to_le32(chap->s2);
325 	if (chap->host_key_len) {
326 		dev_dbg(ctrl->device, "%s: qid %d host public key %*ph\n",
327 			__func__, chap->qid,
328 			chap->host_key_len, chap->host_key);
329 		memcpy(data->rval + 2 * chap->hash_len, chap->host_key,
330 		       chap->host_key_len);
331 	}
332 
333 	return size;
334 }
335 
336 static int nvme_auth_process_dhchap_success1(struct nvme_ctrl *ctrl,
337 		struct nvme_dhchap_queue_context *chap)
338 {
339 	struct nvmf_auth_dhchap_success1_data *data = chap->buf;
340 	size_t size = sizeof(*data);
341 
342 	if (chap->ctrl_key)
343 		size += chap->hash_len;
344 
345 	if (size > CHAP_BUF_SIZE) {
346 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
347 		return NVME_SC_INVALID_FIELD;
348 	}
349 
350 	if (data->hl != chap->hash_len) {
351 		dev_warn(ctrl->device,
352 			 "qid %d: invalid hash length %u\n",
353 			 chap->qid, data->hl);
354 		chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
355 		return NVME_SC_INVALID_FIELD;
356 	}
357 
358 	/* Just print out information for the admin queue */
359 	if (chap->qid == 0)
360 		dev_info(ctrl->device,
361 			 "qid 0: authenticated with hash %s dhgroup %s\n",
362 			 nvme_auth_hmac_name(chap->hash_id),
363 			 nvme_auth_dhgroup_name(chap->dhgroup_id));
364 
365 	if (!data->rvalid)
366 		return 0;
367 
368 	/* Validate controller response */
369 	if (memcmp(chap->response, data->rval, data->hl)) {
370 		dev_dbg(ctrl->device, "%s: qid %d ctrl response %*ph\n",
371 			__func__, chap->qid, (int)chap->hash_len, data->rval);
372 		dev_dbg(ctrl->device, "%s: qid %d host response %*ph\n",
373 			__func__, chap->qid, (int)chap->hash_len,
374 			chap->response);
375 		dev_warn(ctrl->device,
376 			 "qid %d: controller authentication failed\n",
377 			 chap->qid);
378 		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
379 		return NVME_SC_AUTH_REQUIRED;
380 	}
381 
382 	/* Just print out information for the admin queue */
383 	if (chap->qid == 0)
384 		dev_info(ctrl->device,
385 			 "qid 0: controller authenticated\n");
386 	return 0;
387 }
388 
389 static int nvme_auth_set_dhchap_success2_data(struct nvme_ctrl *ctrl,
390 		struct nvme_dhchap_queue_context *chap)
391 {
392 	struct nvmf_auth_dhchap_success2_data *data = chap->buf;
393 	size_t size = sizeof(*data);
394 
395 	memset(chap->buf, 0, size);
396 	data->auth_type = NVME_AUTH_DHCHAP_MESSAGES;
397 	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_SUCCESS2;
398 	data->t_id = cpu_to_le16(chap->transaction);
399 
400 	return size;
401 }
402 
403 static int nvme_auth_set_dhchap_failure2_data(struct nvme_ctrl *ctrl,
404 		struct nvme_dhchap_queue_context *chap)
405 {
406 	struct nvmf_auth_dhchap_failure_data *data = chap->buf;
407 	size_t size = sizeof(*data);
408 
409 	memset(chap->buf, 0, size);
410 	data->auth_type = NVME_AUTH_COMMON_MESSAGES;
411 	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_FAILURE2;
412 	data->t_id = cpu_to_le16(chap->transaction);
413 	data->rescode = NVME_AUTH_DHCHAP_FAILURE_REASON_FAILED;
414 	data->rescode_exp = chap->status;
415 
416 	return size;
417 }
418 
419 static int nvme_auth_dhchap_setup_host_response(struct nvme_ctrl *ctrl,
420 		struct nvme_dhchap_queue_context *chap)
421 {
422 	SHASH_DESC_ON_STACK(shash, chap->shash_tfm);
423 	u8 buf[4], *challenge = chap->c1;
424 	int ret;
425 
426 	dev_dbg(ctrl->device, "%s: qid %d host response seq %u transaction %d\n",
427 		__func__, chap->qid, chap->s1, chap->transaction);
428 
429 	if (!chap->host_response) {
430 		chap->host_response = nvme_auth_transform_key(ctrl->host_key,
431 						ctrl->opts->host->nqn);
432 		if (IS_ERR(chap->host_response)) {
433 			ret = PTR_ERR(chap->host_response);
434 			chap->host_response = NULL;
435 			return ret;
436 		}
437 	} else {
438 		dev_dbg(ctrl->device, "%s: qid %d re-using host response\n",
439 			__func__, chap->qid);
440 	}
441 
442 	ret = crypto_shash_setkey(chap->shash_tfm,
443 			chap->host_response, ctrl->host_key->len);
444 	if (ret) {
445 		dev_warn(ctrl->device, "qid %d: failed to set key, error %d\n",
446 			 chap->qid, ret);
447 		goto out;
448 	}
449 
450 	if (chap->dh_tfm) {
451 		challenge = kmalloc(chap->hash_len, GFP_KERNEL);
452 		if (!challenge) {
453 			ret = -ENOMEM;
454 			goto out;
455 		}
456 		ret = nvme_auth_augmented_challenge(chap->hash_id,
457 						    chap->sess_key,
458 						    chap->sess_key_len,
459 						    chap->c1, challenge,
460 						    chap->hash_len);
461 		if (ret)
462 			goto out;
463 	}
464 
465 	shash->tfm = chap->shash_tfm;
466 	ret = crypto_shash_init(shash);
467 	if (ret)
468 		goto out;
469 	ret = crypto_shash_update(shash, challenge, chap->hash_len);
470 	if (ret)
471 		goto out;
472 	put_unaligned_le32(chap->s1, buf);
473 	ret = crypto_shash_update(shash, buf, 4);
474 	if (ret)
475 		goto out;
476 	put_unaligned_le16(chap->transaction, buf);
477 	ret = crypto_shash_update(shash, buf, 2);
478 	if (ret)
479 		goto out;
480 	memset(buf, 0, sizeof(buf));
481 	ret = crypto_shash_update(shash, buf, 1);
482 	if (ret)
483 		goto out;
484 	ret = crypto_shash_update(shash, "HostHost", 8);
485 	if (ret)
486 		goto out;
487 	ret = crypto_shash_update(shash, ctrl->opts->host->nqn,
488 				  strlen(ctrl->opts->host->nqn));
489 	if (ret)
490 		goto out;
491 	ret = crypto_shash_update(shash, buf, 1);
492 	if (ret)
493 		goto out;
494 	ret = crypto_shash_update(shash, ctrl->opts->subsysnqn,
495 			    strlen(ctrl->opts->subsysnqn));
496 	if (ret)
497 		goto out;
498 	ret = crypto_shash_final(shash, chap->response);
499 out:
500 	if (challenge != chap->c1)
501 		kfree(challenge);
502 	return ret;
503 }
504 
505 static int nvme_auth_dhchap_setup_ctrl_response(struct nvme_ctrl *ctrl,
506 		struct nvme_dhchap_queue_context *chap)
507 {
508 	SHASH_DESC_ON_STACK(shash, chap->shash_tfm);
509 	u8 *ctrl_response;
510 	u8 buf[4], *challenge = chap->c2;
511 	int ret;
512 
513 	ctrl_response = nvme_auth_transform_key(ctrl->ctrl_key,
514 				ctrl->opts->subsysnqn);
515 	if (IS_ERR(ctrl_response)) {
516 		ret = PTR_ERR(ctrl_response);
517 		return ret;
518 	}
519 
520 	ret = crypto_shash_setkey(chap->shash_tfm,
521 			ctrl_response, ctrl->ctrl_key->len);
522 	if (ret) {
523 		dev_warn(ctrl->device, "qid %d: failed to set key, error %d\n",
524 			 chap->qid, ret);
525 		goto out;
526 	}
527 
528 	if (chap->dh_tfm) {
529 		challenge = kmalloc(chap->hash_len, GFP_KERNEL);
530 		if (!challenge) {
531 			ret = -ENOMEM;
532 			goto out;
533 		}
534 		ret = nvme_auth_augmented_challenge(chap->hash_id,
535 						    chap->sess_key,
536 						    chap->sess_key_len,
537 						    chap->c2, challenge,
538 						    chap->hash_len);
539 		if (ret)
540 			goto out;
541 	}
542 	dev_dbg(ctrl->device, "%s: qid %d ctrl response seq %u transaction %d\n",
543 		__func__, chap->qid, chap->s2, chap->transaction);
544 	dev_dbg(ctrl->device, "%s: qid %d challenge %*ph\n",
545 		__func__, chap->qid, (int)chap->hash_len, challenge);
546 	dev_dbg(ctrl->device, "%s: qid %d subsysnqn %s\n",
547 		__func__, chap->qid, ctrl->opts->subsysnqn);
548 	dev_dbg(ctrl->device, "%s: qid %d hostnqn %s\n",
549 		__func__, chap->qid, ctrl->opts->host->nqn);
550 	shash->tfm = chap->shash_tfm;
551 	ret = crypto_shash_init(shash);
552 	if (ret)
553 		goto out;
554 	ret = crypto_shash_update(shash, challenge, chap->hash_len);
555 	if (ret)
556 		goto out;
557 	put_unaligned_le32(chap->s2, buf);
558 	ret = crypto_shash_update(shash, buf, 4);
559 	if (ret)
560 		goto out;
561 	put_unaligned_le16(chap->transaction, buf);
562 	ret = crypto_shash_update(shash, buf, 2);
563 	if (ret)
564 		goto out;
565 	memset(buf, 0, 4);
566 	ret = crypto_shash_update(shash, buf, 1);
567 	if (ret)
568 		goto out;
569 	ret = crypto_shash_update(shash, "Controller", 10);
570 	if (ret)
571 		goto out;
572 	ret = crypto_shash_update(shash, ctrl->opts->subsysnqn,
573 				  strlen(ctrl->opts->subsysnqn));
574 	if (ret)
575 		goto out;
576 	ret = crypto_shash_update(shash, buf, 1);
577 	if (ret)
578 		goto out;
579 	ret = crypto_shash_update(shash, ctrl->opts->host->nqn,
580 				  strlen(ctrl->opts->host->nqn));
581 	if (ret)
582 		goto out;
583 	ret = crypto_shash_final(shash, chap->response);
584 out:
585 	if (challenge != chap->c2)
586 		kfree(challenge);
587 	kfree(ctrl_response);
588 	return ret;
589 }
590 
591 static int nvme_auth_dhchap_exponential(struct nvme_ctrl *ctrl,
592 		struct nvme_dhchap_queue_context *chap)
593 {
594 	int ret;
595 
596 	if (chap->host_key && chap->host_key_len) {
597 		dev_dbg(ctrl->device,
598 			"qid %d: reusing host key\n", chap->qid);
599 		goto gen_sesskey;
600 	}
601 	ret = nvme_auth_gen_privkey(chap->dh_tfm, chap->dhgroup_id);
602 	if (ret < 0) {
603 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
604 		return ret;
605 	}
606 
607 	chap->host_key_len = crypto_kpp_maxsize(chap->dh_tfm);
608 
609 	chap->host_key = kzalloc(chap->host_key_len, GFP_KERNEL);
610 	if (!chap->host_key) {
611 		chap->host_key_len = 0;
612 		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
613 		return -ENOMEM;
614 	}
615 	ret = nvme_auth_gen_pubkey(chap->dh_tfm,
616 				   chap->host_key, chap->host_key_len);
617 	if (ret) {
618 		dev_dbg(ctrl->device,
619 			"failed to generate public key, error %d\n", ret);
620 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
621 		return ret;
622 	}
623 
624 gen_sesskey:
625 	chap->sess_key_len = chap->host_key_len;
626 	chap->sess_key = kmalloc(chap->sess_key_len, GFP_KERNEL);
627 	if (!chap->sess_key) {
628 		chap->sess_key_len = 0;
629 		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
630 		return -ENOMEM;
631 	}
632 
633 	ret = nvme_auth_gen_shared_secret(chap->dh_tfm,
634 					  chap->ctrl_key, chap->ctrl_key_len,
635 					  chap->sess_key, chap->sess_key_len);
636 	if (ret) {
637 		dev_dbg(ctrl->device,
638 			"failed to generate shared secret, error %d\n", ret);
639 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
640 		return ret;
641 	}
642 	dev_dbg(ctrl->device, "shared secret %*ph\n",
643 		(int)chap->sess_key_len, chap->sess_key);
644 	return 0;
645 }
646 
647 static void nvme_auth_reset_dhchap(struct nvme_dhchap_queue_context *chap)
648 {
649 	kfree_sensitive(chap->host_response);
650 	chap->host_response = NULL;
651 	kfree_sensitive(chap->host_key);
652 	chap->host_key = NULL;
653 	chap->host_key_len = 0;
654 	kfree_sensitive(chap->ctrl_key);
655 	chap->ctrl_key = NULL;
656 	chap->ctrl_key_len = 0;
657 	kfree_sensitive(chap->sess_key);
658 	chap->sess_key = NULL;
659 	chap->sess_key_len = 0;
660 	chap->status = 0;
661 	chap->error = 0;
662 	chap->s1 = 0;
663 	chap->s2 = 0;
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 
671 static 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 
680 static 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 = NVME_SC_AUTH_REQUIRED;
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 	if (ret) {
760 		mutex_unlock(&ctrl->dhchap_auth_mutex);
761 		chap->error = ret;
762 		goto fail2;
763 	}
764 	mutex_unlock(&ctrl->dhchap_auth_mutex);
765 
766 	/* DH-HMAC-CHAP Step 3: send reply */
767 	dev_dbg(ctrl->device, "%s: qid %d send reply\n",
768 		__func__, chap->qid);
769 	ret = nvme_auth_set_dhchap_reply_data(ctrl, chap);
770 	if (ret < 0) {
771 		chap->error = ret;
772 		goto fail2;
773 	}
774 
775 	tl = ret;
776 	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
777 	if (ret) {
778 		chap->error = ret;
779 		goto fail2;
780 	}
781 
782 	/* DH-HMAC-CHAP Step 4: receive success1 */
783 	dev_dbg(ctrl->device, "%s: qid %d receive success1\n",
784 		__func__, chap->qid);
785 
786 	memset(chap->buf, 0, CHAP_BUF_SIZE);
787 	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, CHAP_BUF_SIZE,
788 			       false);
789 	if (ret) {
790 		dev_warn(ctrl->device,
791 			 "qid %d failed to receive success1, %s %d\n",
792 			 chap->qid, ret < 0 ? "error" : "nvme status", ret);
793 		chap->error = ret;
794 		return;
795 	}
796 	ret = nvme_auth_receive_validate(ctrl, chap->qid,
797 					 chap->buf, chap->transaction,
798 					 NVME_AUTH_DHCHAP_MESSAGE_SUCCESS1);
799 	if (ret) {
800 		chap->status = ret;
801 		chap->error = NVME_SC_AUTH_REQUIRED;
802 		return;
803 	}
804 
805 	mutex_lock(&ctrl->dhchap_auth_mutex);
806 	if (ctrl->ctrl_key) {
807 		dev_dbg(ctrl->device,
808 			"%s: qid %d controller response\n",
809 			__func__, chap->qid);
810 		ret = nvme_auth_dhchap_setup_ctrl_response(ctrl, chap);
811 		if (ret) {
812 			mutex_unlock(&ctrl->dhchap_auth_mutex);
813 			chap->error = ret;
814 			goto fail2;
815 		}
816 	}
817 	mutex_unlock(&ctrl->dhchap_auth_mutex);
818 
819 	ret = nvme_auth_process_dhchap_success1(ctrl, chap);
820 	if (ret) {
821 		/* Controller authentication failed */
822 		chap->error = NVME_SC_AUTH_REQUIRED;
823 		goto fail2;
824 	}
825 
826 	if (chap->ctrl_key) {
827 		/* DH-HMAC-CHAP Step 5: send success2 */
828 		dev_dbg(ctrl->device, "%s: qid %d send success2\n",
829 			__func__, chap->qid);
830 		tl = nvme_auth_set_dhchap_success2_data(ctrl, chap);
831 		ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
832 		if (ret)
833 			chap->error = ret;
834 	}
835 	if (!ret) {
836 		chap->error = 0;
837 		return;
838 	}
839 
840 fail2:
841 	dev_dbg(ctrl->device, "%s: qid %d send failure2, status %x\n",
842 		__func__, chap->qid, chap->status);
843 	tl = nvme_auth_set_dhchap_failure2_data(ctrl, chap);
844 	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
845 	/*
846 	 * only update error if send failure2 failed and no other
847 	 * error had been set during authentication.
848 	 */
849 	if (ret && !chap->error)
850 		chap->error = ret;
851 }
852 
853 int nvme_auth_negotiate(struct nvme_ctrl *ctrl, int qid)
854 {
855 	struct nvme_dhchap_queue_context *chap;
856 
857 	if (!ctrl->host_key) {
858 		dev_warn(ctrl->device, "qid %d: no key\n", qid);
859 		return -ENOKEY;
860 	}
861 
862 	if (ctrl->opts->dhchap_ctrl_secret && !ctrl->ctrl_key) {
863 		dev_warn(ctrl->device, "qid %d: invalid ctrl key\n", qid);
864 		return -ENOKEY;
865 	}
866 
867 	chap = &ctrl->dhchap_ctxs[qid];
868 	cancel_work_sync(&chap->auth_work);
869 	queue_work(nvme_wq, &chap->auth_work);
870 	return 0;
871 }
872 EXPORT_SYMBOL_GPL(nvme_auth_negotiate);
873 
874 int nvme_auth_wait(struct nvme_ctrl *ctrl, int qid)
875 {
876 	struct nvme_dhchap_queue_context *chap;
877 	int ret;
878 
879 	chap = &ctrl->dhchap_ctxs[qid];
880 	flush_work(&chap->auth_work);
881 	ret = chap->error;
882 	/* clear sensitive info */
883 	nvme_auth_reset_dhchap(chap);
884 	return ret;
885 }
886 EXPORT_SYMBOL_GPL(nvme_auth_wait);
887 
888 static void nvme_ctrl_auth_work(struct work_struct *work)
889 {
890 	struct nvme_ctrl *ctrl =
891 		container_of(work, struct nvme_ctrl, dhchap_auth_work);
892 	int ret, q;
893 
894 	/*
895 	 * If the ctrl is no connected, bail as reconnect will handle
896 	 * authentication.
897 	 */
898 	if (ctrl->state != NVME_CTRL_LIVE)
899 		return;
900 
901 	/* Authenticate admin queue first */
902 	ret = nvme_auth_negotiate(ctrl, 0);
903 	if (ret) {
904 		dev_warn(ctrl->device,
905 			 "qid 0: error %d setting up authentication\n", ret);
906 		return;
907 	}
908 	ret = nvme_auth_wait(ctrl, 0);
909 	if (ret) {
910 		dev_warn(ctrl->device,
911 			 "qid 0: authentication failed\n");
912 		return;
913 	}
914 
915 	for (q = 1; q < ctrl->queue_count; q++) {
916 		ret = nvme_auth_negotiate(ctrl, q);
917 		if (ret) {
918 			dev_warn(ctrl->device,
919 				 "qid %d: error %d setting up authentication\n",
920 				 q, ret);
921 			break;
922 		}
923 	}
924 
925 	/*
926 	 * Failure is a soft-state; credentials remain valid until
927 	 * the controller terminates the connection.
928 	 */
929 	for (q = 1; q < ctrl->queue_count; q++) {
930 		ret = nvme_auth_wait(ctrl, q);
931 		if (ret)
932 			dev_warn(ctrl->device,
933 				 "qid %d: authentication failed\n", q);
934 	}
935 }
936 
937 int nvme_auth_init_ctrl(struct nvme_ctrl *ctrl)
938 {
939 	struct nvme_dhchap_queue_context *chap;
940 	int i, ret;
941 
942 	mutex_init(&ctrl->dhchap_auth_mutex);
943 	INIT_WORK(&ctrl->dhchap_auth_work, nvme_ctrl_auth_work);
944 	if (!ctrl->opts)
945 		return 0;
946 	ret = nvme_auth_generate_key(ctrl->opts->dhchap_secret,
947 			&ctrl->host_key);
948 	if (ret)
949 		return ret;
950 	ret = nvme_auth_generate_key(ctrl->opts->dhchap_ctrl_secret,
951 			&ctrl->ctrl_key);
952 	if (ret)
953 		goto err_free_dhchap_secret;
954 
955 	if (!ctrl->opts->dhchap_secret && !ctrl->opts->dhchap_ctrl_secret)
956 		return ret;
957 
958 	ctrl->dhchap_ctxs = kvcalloc(ctrl_max_dhchaps(ctrl),
959 				sizeof(*chap), GFP_KERNEL);
960 	if (!ctrl->dhchap_ctxs) {
961 		ret = -ENOMEM;
962 		goto err_free_dhchap_ctrl_secret;
963 	}
964 
965 	for (i = 0; i < ctrl_max_dhchaps(ctrl); i++) {
966 		chap = &ctrl->dhchap_ctxs[i];
967 		chap->qid = i;
968 		chap->ctrl = ctrl;
969 		INIT_WORK(&chap->auth_work, nvme_queue_auth_work);
970 	}
971 
972 	return 0;
973 err_free_dhchap_ctrl_secret:
974 	nvme_auth_free_key(ctrl->ctrl_key);
975 	ctrl->ctrl_key = NULL;
976 err_free_dhchap_secret:
977 	nvme_auth_free_key(ctrl->host_key);
978 	ctrl->host_key = NULL;
979 	return ret;
980 }
981 EXPORT_SYMBOL_GPL(nvme_auth_init_ctrl);
982 
983 void nvme_auth_stop(struct nvme_ctrl *ctrl)
984 {
985 	cancel_work_sync(&ctrl->dhchap_auth_work);
986 }
987 EXPORT_SYMBOL_GPL(nvme_auth_stop);
988 
989 void nvme_auth_free(struct nvme_ctrl *ctrl)
990 {
991 	int i;
992 
993 	if (ctrl->dhchap_ctxs) {
994 		for (i = 0; i < ctrl_max_dhchaps(ctrl); i++)
995 			nvme_auth_free_dhchap(&ctrl->dhchap_ctxs[i]);
996 		kfree(ctrl->dhchap_ctxs);
997 	}
998 	if (ctrl->host_key) {
999 		nvme_auth_free_key(ctrl->host_key);
1000 		ctrl->host_key = NULL;
1001 	}
1002 	if (ctrl->ctrl_key) {
1003 		nvme_auth_free_key(ctrl->ctrl_key);
1004 		ctrl->ctrl_key = NULL;
1005 	}
1006 }
1007 EXPORT_SYMBOL_GPL(nvme_auth_free);
1008 
1009 int __init nvme_init_auth(void)
1010 {
1011 	nvme_chap_buf_cache = kmem_cache_create("nvme-chap-buf-cache",
1012 				CHAP_BUF_SIZE, 0, SLAB_HWCACHE_ALIGN, NULL);
1013 	if (!nvme_chap_buf_cache)
1014 		return -ENOMEM;
1015 
1016 	nvme_chap_buf_pool = mempool_create(16, mempool_alloc_slab,
1017 			mempool_free_slab, nvme_chap_buf_cache);
1018 	if (!nvme_chap_buf_pool)
1019 		goto err_destroy_chap_buf_cache;
1020 
1021 	return 0;
1022 err_destroy_chap_buf_cache:
1023 	kmem_cache_destroy(nvme_chap_buf_cache);
1024 	return -ENOMEM;
1025 }
1026 
1027 void __exit nvme_exit_auth(void)
1028 {
1029 	mempool_destroy(nvme_chap_buf_pool);
1030 	kmem_cache_destroy(nvme_chap_buf_cache);
1031 }
1032