xref: /linux/drivers/nvme/host/auth.c (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
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 	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 
49 static struct workqueue_struct *nvme_auth_wq;
50 
51 #define nvme_auth_flags_from_qid(qid) \
52 	(qid == 0) ? 0 : BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED
53 #define nvme_auth_queue_from_qid(ctrl, qid) \
54 	(qid == 0) ? (ctrl)->fabrics_q : (ctrl)->connect_q
55 
56 static inline int ctrl_max_dhchaps(struct nvme_ctrl *ctrl)
57 {
58 	return ctrl->opts->nr_io_queues + ctrl->opts->nr_write_queues +
59 			ctrl->opts->nr_poll_queues + 1;
60 }
61 
62 static int nvme_auth_submit(struct nvme_ctrl *ctrl, int qid,
63 			    void *data, size_t data_len, bool auth_send)
64 {
65 	struct nvme_command cmd = {};
66 	blk_mq_req_flags_t flags = nvme_auth_flags_from_qid(qid);
67 	struct request_queue *q = nvme_auth_queue_from_qid(ctrl, qid);
68 	int ret;
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,
84 				     0, flags);
85 	if (ret > 0)
86 		dev_warn(ctrl->device,
87 			"qid %d auth_send failed with status %d\n", qid, ret);
88 	else if (ret < 0)
89 		dev_err(ctrl->device,
90 			"qid %d auth_send failed with error %d\n", qid, ret);
91 	return ret;
92 }
93 
94 static int nvme_auth_receive_validate(struct nvme_ctrl *ctrl, int qid,
95 		struct nvmf_auth_dhchap_failure_data *data,
96 		u16 transaction, u8 expected_msg)
97 {
98 	dev_dbg(ctrl->device, "%s: qid %d auth_type %d auth_id %x\n",
99 		__func__, qid, data->auth_type, data->auth_id);
100 
101 	if (data->auth_type == NVME_AUTH_COMMON_MESSAGES &&
102 	    data->auth_id == NVME_AUTH_DHCHAP_MESSAGE_FAILURE1) {
103 		return data->rescode_exp;
104 	}
105 	if (data->auth_type != NVME_AUTH_DHCHAP_MESSAGES ||
106 	    data->auth_id != expected_msg) {
107 		dev_warn(ctrl->device,
108 			 "qid %d invalid message %02x/%02x\n",
109 			 qid, data->auth_type, data->auth_id);
110 		return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_MESSAGE;
111 	}
112 	if (le16_to_cpu(data->t_id) != transaction) {
113 		dev_warn(ctrl->device,
114 			 "qid %d invalid transaction ID %d\n",
115 			 qid, le16_to_cpu(data->t_id));
116 		return NVME_AUTH_DHCHAP_FAILURE_INCORRECT_MESSAGE;
117 	}
118 	return 0;
119 }
120 
121 static int nvme_auth_set_dhchap_negotiate_data(struct nvme_ctrl *ctrl,
122 		struct nvme_dhchap_queue_context *chap)
123 {
124 	struct nvmf_auth_dhchap_negotiate_data *data = chap->buf;
125 	size_t size = sizeof(*data) + sizeof(union nvmf_auth_protocol);
126 
127 	if (size > CHAP_BUF_SIZE) {
128 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
129 		return -EINVAL;
130 	}
131 	memset((u8 *)chap->buf, 0, size);
132 	data->auth_type = NVME_AUTH_COMMON_MESSAGES;
133 	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_NEGOTIATE;
134 	data->t_id = cpu_to_le16(chap->transaction);
135 	data->sc_c = 0; /* No secure channel concatenation */
136 	data->napd = 1;
137 	data->auth_protocol[0].dhchap.authid = NVME_AUTH_DHCHAP_AUTH_ID;
138 	data->auth_protocol[0].dhchap.halen = 3;
139 	data->auth_protocol[0].dhchap.dhlen = 6;
140 	data->auth_protocol[0].dhchap.idlist[0] = NVME_AUTH_HASH_SHA256;
141 	data->auth_protocol[0].dhchap.idlist[1] = NVME_AUTH_HASH_SHA384;
142 	data->auth_protocol[0].dhchap.idlist[2] = NVME_AUTH_HASH_SHA512;
143 	data->auth_protocol[0].dhchap.idlist[30] = NVME_AUTH_DHGROUP_NULL;
144 	data->auth_protocol[0].dhchap.idlist[31] = NVME_AUTH_DHGROUP_2048;
145 	data->auth_protocol[0].dhchap.idlist[32] = NVME_AUTH_DHGROUP_3072;
146 	data->auth_protocol[0].dhchap.idlist[33] = NVME_AUTH_DHGROUP_4096;
147 	data->auth_protocol[0].dhchap.idlist[34] = NVME_AUTH_DHGROUP_6144;
148 	data->auth_protocol[0].dhchap.idlist[35] = NVME_AUTH_DHGROUP_8192;
149 
150 	return size;
151 }
152 
153 static int nvme_auth_process_dhchap_challenge(struct nvme_ctrl *ctrl,
154 		struct nvme_dhchap_queue_context *chap)
155 {
156 	struct nvmf_auth_dhchap_challenge_data *data = chap->buf;
157 	u16 dhvlen = le16_to_cpu(data->dhvlen);
158 	size_t size = sizeof(*data) + data->hl + dhvlen;
159 	const char *gid_name = nvme_auth_dhgroup_name(data->dhgid);
160 	const char *hmac_name, *kpp_name;
161 
162 	if (size > CHAP_BUF_SIZE) {
163 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
164 		return -EINVAL;
165 	}
166 
167 	hmac_name = nvme_auth_hmac_name(data->hashid);
168 	if (!hmac_name) {
169 		dev_warn(ctrl->device,
170 			 "qid %d: invalid HASH ID %d\n",
171 			 chap->qid, data->hashid);
172 		chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
173 		return -EPROTO;
174 	}
175 
176 	if (chap->hash_id == data->hashid && chap->shash_tfm &&
177 	    !strcmp(crypto_shash_alg_name(chap->shash_tfm), hmac_name) &&
178 	    crypto_shash_digestsize(chap->shash_tfm) == data->hl) {
179 		dev_dbg(ctrl->device,
180 			"qid %d: reuse existing hash %s\n",
181 			chap->qid, hmac_name);
182 		goto select_kpp;
183 	}
184 
185 	/* Reset if hash cannot be reused */
186 	if (chap->shash_tfm) {
187 		crypto_free_shash(chap->shash_tfm);
188 		chap->hash_id = 0;
189 		chap->hash_len = 0;
190 	}
191 	chap->shash_tfm = crypto_alloc_shash(hmac_name, 0,
192 					     CRYPTO_ALG_ALLOCATES_MEMORY);
193 	if (IS_ERR(chap->shash_tfm)) {
194 		dev_warn(ctrl->device,
195 			 "qid %d: failed to allocate hash %s, error %ld\n",
196 			 chap->qid, hmac_name, PTR_ERR(chap->shash_tfm));
197 		chap->shash_tfm = NULL;
198 		chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
199 		return -ENOMEM;
200 	}
201 
202 	if (crypto_shash_digestsize(chap->shash_tfm) != data->hl) {
203 		dev_warn(ctrl->device,
204 			 "qid %d: invalid hash length %d\n",
205 			 chap->qid, data->hl);
206 		crypto_free_shash(chap->shash_tfm);
207 		chap->shash_tfm = NULL;
208 		chap->status = NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
209 		return -EPROTO;
210 	}
211 
212 	chap->hash_id = data->hashid;
213 	chap->hash_len = data->hl;
214 	dev_dbg(ctrl->device, "qid %d: selected hash %s\n",
215 		chap->qid, hmac_name);
216 
217 select_kpp:
218 	kpp_name = nvme_auth_dhgroup_kpp(data->dhgid);
219 	if (!kpp_name) {
220 		dev_warn(ctrl->device,
221 			 "qid %d: invalid DH group id %d\n",
222 			 chap->qid, data->dhgid);
223 		chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
224 		/* Leave previous dh_tfm intact */
225 		return -EPROTO;
226 	}
227 
228 	if (chap->dhgroup_id == data->dhgid &&
229 	    (data->dhgid == NVME_AUTH_DHGROUP_NULL || chap->dh_tfm)) {
230 		dev_dbg(ctrl->device,
231 			"qid %d: reuse existing DH group %s\n",
232 			chap->qid, gid_name);
233 		goto skip_kpp;
234 	}
235 
236 	/* Reset dh_tfm if it can't be reused */
237 	if (chap->dh_tfm) {
238 		crypto_free_kpp(chap->dh_tfm);
239 		chap->dh_tfm = NULL;
240 	}
241 
242 	if (data->dhgid != NVME_AUTH_DHGROUP_NULL) {
243 		if (dhvlen == 0) {
244 			dev_warn(ctrl->device,
245 				 "qid %d: empty DH value\n",
246 				 chap->qid);
247 			chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
248 			return -EPROTO;
249 		}
250 
251 		chap->dh_tfm = crypto_alloc_kpp(kpp_name, 0, 0);
252 		if (IS_ERR(chap->dh_tfm)) {
253 			int ret = PTR_ERR(chap->dh_tfm);
254 
255 			dev_warn(ctrl->device,
256 				 "qid %d: error %d initializing DH group %s\n",
257 				 chap->qid, ret, gid_name);
258 			chap->status = NVME_AUTH_DHCHAP_FAILURE_DHGROUP_UNUSABLE;
259 			chap->dh_tfm = NULL;
260 			return ret;
261 		}
262 		dev_dbg(ctrl->device, "qid %d: selected DH group %s\n",
263 			chap->qid, gid_name);
264 	} else if (dhvlen != 0) {
265 		dev_warn(ctrl->device,
266 			 "qid %d: invalid DH value for NULL DH\n",
267 			 chap->qid);
268 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
269 		return -EPROTO;
270 	}
271 	chap->dhgroup_id = data->dhgid;
272 
273 skip_kpp:
274 	chap->s1 = le32_to_cpu(data->seqnum);
275 	memcpy(chap->c1, data->cval, chap->hash_len);
276 	if (dhvlen) {
277 		chap->ctrl_key = kmalloc(dhvlen, GFP_KERNEL);
278 		if (!chap->ctrl_key) {
279 			chap->status = NVME_AUTH_DHCHAP_FAILURE_FAILED;
280 			return -ENOMEM;
281 		}
282 		chap->ctrl_key_len = dhvlen;
283 		memcpy(chap->ctrl_key, data->cval + chap->hash_len,
284 		       dhvlen);
285 		dev_dbg(ctrl->device, "ctrl public key %*ph\n",
286 			 (int)chap->ctrl_key_len, chap->ctrl_key);
287 	}
288 
289 	return 0;
290 }
291 
292 static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
293 		struct nvme_dhchap_queue_context *chap)
294 {
295 	struct nvmf_auth_dhchap_reply_data *data = chap->buf;
296 	size_t size = sizeof(*data);
297 
298 	size += 2 * chap->hash_len;
299 
300 	if (chap->host_key_len)
301 		size += chap->host_key_len;
302 
303 	if (size > CHAP_BUF_SIZE) {
304 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
305 		return -EINVAL;
306 	}
307 
308 	memset(chap->buf, 0, size);
309 	data->auth_type = NVME_AUTH_DHCHAP_MESSAGES;
310 	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_REPLY;
311 	data->t_id = cpu_to_le16(chap->transaction);
312 	data->hl = chap->hash_len;
313 	data->dhvlen = cpu_to_le16(chap->host_key_len);
314 	memcpy(data->rval, chap->response, chap->hash_len);
315 	if (ctrl->ctrl_key) {
316 		chap->bi_directional = true;
317 		get_random_bytes(chap->c2, chap->hash_len);
318 		data->cvalid = 1;
319 		memcpy(data->rval + chap->hash_len, chap->c2,
320 		       chap->hash_len);
321 		dev_dbg(ctrl->device, "%s: qid %d ctrl challenge %*ph\n",
322 			__func__, chap->qid, (int)chap->hash_len, chap->c2);
323 	} else {
324 		memset(chap->c2, 0, chap->hash_len);
325 	}
326 	chap->s2 = nvme_auth_get_seqnum();
327 	data->seqnum = cpu_to_le32(chap->s2);
328 	if (chap->host_key_len) {
329 		dev_dbg(ctrl->device, "%s: qid %d host public key %*ph\n",
330 			__func__, chap->qid,
331 			chap->host_key_len, chap->host_key);
332 		memcpy(data->rval + 2 * chap->hash_len, chap->host_key,
333 		       chap->host_key_len);
334 	}
335 
336 	return size;
337 }
338 
339 static int nvme_auth_process_dhchap_success1(struct nvme_ctrl *ctrl,
340 		struct nvme_dhchap_queue_context *chap)
341 {
342 	struct nvmf_auth_dhchap_success1_data *data = chap->buf;
343 	size_t size = sizeof(*data) + chap->hash_len;
344 
345 	if (size > CHAP_BUF_SIZE) {
346 		chap->status = NVME_AUTH_DHCHAP_FAILURE_INCORRECT_PAYLOAD;
347 		return -EINVAL;
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 -EPROTO;
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 -ECONNREFUSED;
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->transformed_key) {
430 		chap->transformed_key = nvme_auth_transform_key(ctrl->host_key,
431 						ctrl->opts->host->nqn);
432 		if (IS_ERR(chap->transformed_key)) {
433 			ret = PTR_ERR(chap->transformed_key);
434 			chap->transformed_key = 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->transformed_key->key, chap->transformed_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 	struct nvme_dhchap_key *transformed_key;
510 	u8 buf[4], *challenge = chap->c2;
511 	int ret;
512 
513 	transformed_key = nvme_auth_transform_key(ctrl->ctrl_key,
514 				ctrl->opts->subsysnqn);
515 	if (IS_ERR(transformed_key)) {
516 		ret = PTR_ERR(transformed_key);
517 		return ret;
518 	}
519 
520 	ret = crypto_shash_setkey(chap->shash_tfm,
521 			transformed_key->key, transformed_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 	nvme_auth_free_key(transformed_key);
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 	nvme_auth_free_key(chap->transformed_key);
650 	chap->transformed_key = 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->bi_directional = false;
665 	chap->transaction = 0;
666 	memset(chap->c1, 0, sizeof(chap->c1));
667 	memset(chap->c2, 0, sizeof(chap->c2));
668 	mempool_free(chap->buf, nvme_chap_buf_pool);
669 	chap->buf = NULL;
670 }
671 
672 static void nvme_auth_free_dhchap(struct nvme_dhchap_queue_context *chap)
673 {
674 	nvme_auth_reset_dhchap(chap);
675 	if (chap->shash_tfm)
676 		crypto_free_shash(chap->shash_tfm);
677 	if (chap->dh_tfm)
678 		crypto_free_kpp(chap->dh_tfm);
679 }
680 
681 static void nvme_queue_auth_work(struct work_struct *work)
682 {
683 	struct nvme_dhchap_queue_context *chap =
684 		container_of(work, struct nvme_dhchap_queue_context, auth_work);
685 	struct nvme_ctrl *ctrl = chap->ctrl;
686 	size_t tl;
687 	int ret = 0;
688 
689 	/*
690 	 * Allocate a large enough buffer for the entire negotiation:
691 	 * 4k is enough to ffdhe8192.
692 	 */
693 	chap->buf = mempool_alloc(nvme_chap_buf_pool, GFP_KERNEL);
694 	if (!chap->buf) {
695 		chap->error = -ENOMEM;
696 		return;
697 	}
698 
699 	chap->transaction = ctrl->transaction++;
700 
701 	/* DH-HMAC-CHAP Step 1: send negotiate */
702 	dev_dbg(ctrl->device, "%s: qid %d send negotiate\n",
703 		__func__, chap->qid);
704 	ret = nvme_auth_set_dhchap_negotiate_data(ctrl, chap);
705 	if (ret < 0) {
706 		chap->error = ret;
707 		return;
708 	}
709 	tl = ret;
710 	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
711 	if (ret) {
712 		chap->error = ret;
713 		return;
714 	}
715 
716 	/* DH-HMAC-CHAP Step 2: receive challenge */
717 	dev_dbg(ctrl->device, "%s: qid %d receive challenge\n",
718 		__func__, chap->qid);
719 
720 	memset(chap->buf, 0, CHAP_BUF_SIZE);
721 	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, CHAP_BUF_SIZE,
722 			       false);
723 	if (ret) {
724 		dev_warn(ctrl->device,
725 			 "qid %d failed to receive challenge, %s %d\n",
726 			 chap->qid, ret < 0 ? "error" : "nvme status", ret);
727 		chap->error = ret;
728 		return;
729 	}
730 	ret = nvme_auth_receive_validate(ctrl, chap->qid, chap->buf, chap->transaction,
731 					 NVME_AUTH_DHCHAP_MESSAGE_CHALLENGE);
732 	if (ret) {
733 		chap->status = ret;
734 		chap->error = -ECONNREFUSED;
735 		return;
736 	}
737 
738 	ret = nvme_auth_process_dhchap_challenge(ctrl, chap);
739 	if (ret) {
740 		/* Invalid challenge parameters */
741 		chap->error = ret;
742 		goto fail2;
743 	}
744 
745 	if (chap->ctrl_key_len) {
746 		dev_dbg(ctrl->device,
747 			"%s: qid %d DH exponential\n",
748 			__func__, chap->qid);
749 		ret = nvme_auth_dhchap_exponential(ctrl, chap);
750 		if (ret) {
751 			chap->error = ret;
752 			goto fail2;
753 		}
754 	}
755 
756 	dev_dbg(ctrl->device, "%s: qid %d host response\n",
757 		__func__, chap->qid);
758 	mutex_lock(&ctrl->dhchap_auth_mutex);
759 	ret = nvme_auth_dhchap_setup_host_response(ctrl, chap);
760 	if (ret) {
761 		mutex_unlock(&ctrl->dhchap_auth_mutex);
762 		chap->error = ret;
763 		goto fail2;
764 	}
765 	mutex_unlock(&ctrl->dhchap_auth_mutex);
766 
767 	/* DH-HMAC-CHAP Step 3: send reply */
768 	dev_dbg(ctrl->device, "%s: qid %d send reply\n",
769 		__func__, chap->qid);
770 	ret = nvme_auth_set_dhchap_reply_data(ctrl, chap);
771 	if (ret < 0) {
772 		chap->error = ret;
773 		goto fail2;
774 	}
775 
776 	tl = ret;
777 	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
778 	if (ret) {
779 		chap->error = ret;
780 		goto fail2;
781 	}
782 
783 	/* DH-HMAC-CHAP Step 4: receive success1 */
784 	dev_dbg(ctrl->device, "%s: qid %d receive success1\n",
785 		__func__, chap->qid);
786 
787 	memset(chap->buf, 0, CHAP_BUF_SIZE);
788 	ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, CHAP_BUF_SIZE,
789 			       false);
790 	if (ret) {
791 		dev_warn(ctrl->device,
792 			 "qid %d failed to receive success1, %s %d\n",
793 			 chap->qid, ret < 0 ? "error" : "nvme status", ret);
794 		chap->error = ret;
795 		return;
796 	}
797 	ret = nvme_auth_receive_validate(ctrl, chap->qid,
798 					 chap->buf, chap->transaction,
799 					 NVME_AUTH_DHCHAP_MESSAGE_SUCCESS1);
800 	if (ret) {
801 		chap->status = ret;
802 		chap->error = -ECONNREFUSED;
803 		return;
804 	}
805 
806 	mutex_lock(&ctrl->dhchap_auth_mutex);
807 	if (ctrl->ctrl_key) {
808 		dev_dbg(ctrl->device,
809 			"%s: qid %d controller response\n",
810 			__func__, chap->qid);
811 		ret = nvme_auth_dhchap_setup_ctrl_response(ctrl, chap);
812 		if (ret) {
813 			mutex_unlock(&ctrl->dhchap_auth_mutex);
814 			chap->error = ret;
815 			goto fail2;
816 		}
817 	}
818 	mutex_unlock(&ctrl->dhchap_auth_mutex);
819 
820 	ret = nvme_auth_process_dhchap_success1(ctrl, chap);
821 	if (ret) {
822 		/* Controller authentication failed */
823 		chap->error = -ECONNREFUSED;
824 		goto fail2;
825 	}
826 
827 	if (chap->bi_directional) {
828 		/* DH-HMAC-CHAP Step 5: send success2 */
829 		dev_dbg(ctrl->device, "%s: qid %d send success2\n",
830 			__func__, chap->qid);
831 		tl = nvme_auth_set_dhchap_success2_data(ctrl, chap);
832 		ret = nvme_auth_submit(ctrl, chap->qid, chap->buf, tl, true);
833 		if (ret)
834 			chap->error = ret;
835 	}
836 	if (!ret) {
837 		chap->error = 0;
838 		return;
839 	}
840 
841 fail2:
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 
854 int 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 }
873 EXPORT_SYMBOL_GPL(nvme_auth_negotiate);
874 
875 int 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 }
887 EXPORT_SYMBOL_GPL(nvme_auth_wait);
888 
889 static 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 (ctrl->state != 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 
938 int 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;
974 err_free_dhchap_ctrl_secret:
975 	nvme_auth_free_key(ctrl->ctrl_key);
976 	ctrl->ctrl_key = NULL;
977 err_free_dhchap_secret:
978 	nvme_auth_free_key(ctrl->host_key);
979 	ctrl->host_key = NULL;
980 	return ret;
981 }
982 EXPORT_SYMBOL_GPL(nvme_auth_init_ctrl);
983 
984 void nvme_auth_stop(struct nvme_ctrl *ctrl)
985 {
986 	cancel_work_sync(&ctrl->dhchap_auth_work);
987 }
988 EXPORT_SYMBOL_GPL(nvme_auth_stop);
989 
990 void 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 }
1008 EXPORT_SYMBOL_GPL(nvme_auth_free);
1009 
1010 int __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;
1028 err_destroy_chap_buf_cache:
1029 	kmem_cache_destroy(nvme_chap_buf_cache);
1030 err_destroy_workqueue:
1031 	destroy_workqueue(nvme_auth_wq);
1032 	return -ENOMEM;
1033 }
1034 
1035 void __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