xref: /openbmc/linux/fs/smb/server/auth.c (revision fe4549b1)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
4  *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/fs.h>
9 #include <linux/uaccess.h>
10 #include <linux/backing-dev.h>
11 #include <linux/writeback.h>
12 #include <linux/uio.h>
13 #include <linux/xattr.h>
14 #include <crypto/hash.h>
15 #include <crypto/aead.h>
16 #include <linux/random.h>
17 #include <linux/scatterlist.h>
18 
19 #include "auth.h"
20 #include "glob.h"
21 
22 #include <linux/fips.h>
23 #include <crypto/des.h>
24 
25 #include "server.h"
26 #include "smb_common.h"
27 #include "connection.h"
28 #include "mgmt/user_session.h"
29 #include "mgmt/user_config.h"
30 #include "crypto_ctx.h"
31 #include "transport_ipc.h"
32 #include "../common/arc4.h"
33 
34 /*
35  * Fixed format data defining GSS header and fixed string
36  * "not_defined_in_RFC4178@please_ignore".
37  * So sec blob data in neg phase could be generated statically.
38  */
39 static char NEGOTIATE_GSS_HEADER[AUTH_GSS_LENGTH] = {
40 #ifdef CONFIG_SMB_SERVER_KERBEROS5
41 	0x60, 0x5e, 0x06, 0x06, 0x2b, 0x06, 0x01, 0x05,
42 	0x05, 0x02, 0xa0, 0x54, 0x30, 0x52, 0xa0, 0x24,
43 	0x30, 0x22, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
44 	0xf7, 0x12, 0x01, 0x02, 0x02, 0x06, 0x09, 0x2a,
45 	0x86, 0x48, 0x82, 0xf7, 0x12, 0x01, 0x02, 0x02,
46 	0x06, 0x0a, 0x2b, 0x06, 0x01, 0x04, 0x01, 0x82,
47 	0x37, 0x02, 0x02, 0x0a, 0xa3, 0x2a, 0x30, 0x28,
48 	0xa0, 0x26, 0x1b, 0x24, 0x6e, 0x6f, 0x74, 0x5f,
49 	0x64, 0x65, 0x66, 0x69, 0x6e, 0x65, 0x64, 0x5f,
50 	0x69, 0x6e, 0x5f, 0x52, 0x46, 0x43, 0x34, 0x31,
51 	0x37, 0x38, 0x40, 0x70, 0x6c, 0x65, 0x61, 0x73,
52 	0x65, 0x5f, 0x69, 0x67, 0x6e, 0x6f, 0x72, 0x65
53 #else
54 	0x60, 0x48, 0x06, 0x06, 0x2b, 0x06, 0x01, 0x05,
55 	0x05, 0x02, 0xa0, 0x3e, 0x30, 0x3c, 0xa0, 0x0e,
56 	0x30, 0x0c, 0x06, 0x0a, 0x2b, 0x06, 0x01, 0x04,
57 	0x01, 0x82, 0x37, 0x02, 0x02, 0x0a, 0xa3, 0x2a,
58 	0x30, 0x28, 0xa0, 0x26, 0x1b, 0x24, 0x6e, 0x6f,
59 	0x74, 0x5f, 0x64, 0x65, 0x66, 0x69, 0x6e, 0x65,
60 	0x64, 0x5f, 0x69, 0x6e, 0x5f, 0x52, 0x46, 0x43,
61 	0x34, 0x31, 0x37, 0x38, 0x40, 0x70, 0x6c, 0x65,
62 	0x61, 0x73, 0x65, 0x5f, 0x69, 0x67, 0x6e, 0x6f,
63 	0x72, 0x65
64 #endif
65 };
66 
67 void ksmbd_copy_gss_neg_header(void *buf)
68 {
69 	memcpy(buf, NEGOTIATE_GSS_HEADER, AUTH_GSS_LENGTH);
70 }
71 
72 /**
73  * ksmbd_gen_sess_key() - function to generate session key
74  * @sess:	session of connection
75  * @hash:	source hash value to be used for find session key
76  * @hmac:	source hmac value to be used for finding session key
77  *
78  */
79 static int ksmbd_gen_sess_key(struct ksmbd_session *sess, char *hash,
80 			      char *hmac)
81 {
82 	struct ksmbd_crypto_ctx *ctx;
83 	int rc;
84 
85 	ctx = ksmbd_crypto_ctx_find_hmacmd5();
86 	if (!ctx) {
87 		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
88 		return -ENOMEM;
89 	}
90 
91 	rc = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
92 				 hash,
93 				 CIFS_HMAC_MD5_HASH_SIZE);
94 	if (rc) {
95 		ksmbd_debug(AUTH, "hmacmd5 set key fail error %d\n", rc);
96 		goto out;
97 	}
98 
99 	rc = crypto_shash_init(CRYPTO_HMACMD5(ctx));
100 	if (rc) {
101 		ksmbd_debug(AUTH, "could not init hmacmd5 error %d\n", rc);
102 		goto out;
103 	}
104 
105 	rc = crypto_shash_update(CRYPTO_HMACMD5(ctx),
106 				 hmac,
107 				 SMB2_NTLMV2_SESSKEY_SIZE);
108 	if (rc) {
109 		ksmbd_debug(AUTH, "Could not update with response error %d\n", rc);
110 		goto out;
111 	}
112 
113 	rc = crypto_shash_final(CRYPTO_HMACMD5(ctx), sess->sess_key);
114 	if (rc) {
115 		ksmbd_debug(AUTH, "Could not generate hmacmd5 hash error %d\n", rc);
116 		goto out;
117 	}
118 
119 out:
120 	ksmbd_release_crypto_ctx(ctx);
121 	return rc;
122 }
123 
124 static int calc_ntlmv2_hash(struct ksmbd_conn *conn, struct ksmbd_session *sess,
125 			    char *ntlmv2_hash, char *dname)
126 {
127 	int ret, len, conv_len;
128 	wchar_t *domain = NULL;
129 	__le16 *uniname = NULL;
130 	struct ksmbd_crypto_ctx *ctx;
131 
132 	ctx = ksmbd_crypto_ctx_find_hmacmd5();
133 	if (!ctx) {
134 		ksmbd_debug(AUTH, "can't generate ntlmv2 hash\n");
135 		return -ENOMEM;
136 	}
137 
138 	ret = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
139 				  user_passkey(sess->user),
140 				  CIFS_ENCPWD_SIZE);
141 	if (ret) {
142 		ksmbd_debug(AUTH, "Could not set NT Hash as a key\n");
143 		goto out;
144 	}
145 
146 	ret = crypto_shash_init(CRYPTO_HMACMD5(ctx));
147 	if (ret) {
148 		ksmbd_debug(AUTH, "could not init hmacmd5\n");
149 		goto out;
150 	}
151 
152 	/* convert user_name to unicode */
153 	len = strlen(user_name(sess->user));
154 	uniname = kzalloc(2 + UNICODE_LEN(len), GFP_KERNEL);
155 	if (!uniname) {
156 		ret = -ENOMEM;
157 		goto out;
158 	}
159 
160 	conv_len = smb_strtoUTF16(uniname, user_name(sess->user), len,
161 				  conn->local_nls);
162 	if (conv_len < 0 || conv_len > len) {
163 		ret = -EINVAL;
164 		goto out;
165 	}
166 	UniStrupr(uniname);
167 
168 	ret = crypto_shash_update(CRYPTO_HMACMD5(ctx),
169 				  (char *)uniname,
170 				  UNICODE_LEN(conv_len));
171 	if (ret) {
172 		ksmbd_debug(AUTH, "Could not update with user\n");
173 		goto out;
174 	}
175 
176 	/* Convert domain name or conn name to unicode and uppercase */
177 	len = strlen(dname);
178 	domain = kzalloc(2 + UNICODE_LEN(len), GFP_KERNEL);
179 	if (!domain) {
180 		ret = -ENOMEM;
181 		goto out;
182 	}
183 
184 	conv_len = smb_strtoUTF16((__le16 *)domain, dname, len,
185 				  conn->local_nls);
186 	if (conv_len < 0 || conv_len > len) {
187 		ret = -EINVAL;
188 		goto out;
189 	}
190 
191 	ret = crypto_shash_update(CRYPTO_HMACMD5(ctx),
192 				  (char *)domain,
193 				  UNICODE_LEN(conv_len));
194 	if (ret) {
195 		ksmbd_debug(AUTH, "Could not update with domain\n");
196 		goto out;
197 	}
198 
199 	ret = crypto_shash_final(CRYPTO_HMACMD5(ctx), ntlmv2_hash);
200 	if (ret)
201 		ksmbd_debug(AUTH, "Could not generate md5 hash\n");
202 out:
203 	kfree(uniname);
204 	kfree(domain);
205 	ksmbd_release_crypto_ctx(ctx);
206 	return ret;
207 }
208 
209 /**
210  * ksmbd_auth_ntlmv2() - NTLMv2 authentication handler
211  * @conn:		connection
212  * @sess:		session of connection
213  * @ntlmv2:		NTLMv2 challenge response
214  * @blen:		NTLMv2 blob length
215  * @domain_name:	domain name
216  * @cryptkey:		session crypto key
217  *
218  * Return:	0 on success, error number on error
219  */
220 int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess,
221 		      struct ntlmv2_resp *ntlmv2, int blen, char *domain_name,
222 		      char *cryptkey)
223 {
224 	char ntlmv2_hash[CIFS_ENCPWD_SIZE];
225 	char ntlmv2_rsp[CIFS_HMAC_MD5_HASH_SIZE];
226 	struct ksmbd_crypto_ctx *ctx = NULL;
227 	char *construct = NULL;
228 	int rc, len;
229 
230 	rc = calc_ntlmv2_hash(conn, sess, ntlmv2_hash, domain_name);
231 	if (rc) {
232 		ksmbd_debug(AUTH, "could not get v2 hash rc %d\n", rc);
233 		goto out;
234 	}
235 
236 	ctx = ksmbd_crypto_ctx_find_hmacmd5();
237 	if (!ctx) {
238 		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
239 		return -ENOMEM;
240 	}
241 
242 	rc = crypto_shash_setkey(CRYPTO_HMACMD5_TFM(ctx),
243 				 ntlmv2_hash,
244 				 CIFS_HMAC_MD5_HASH_SIZE);
245 	if (rc) {
246 		ksmbd_debug(AUTH, "Could not set NTLMV2 Hash as a key\n");
247 		goto out;
248 	}
249 
250 	rc = crypto_shash_init(CRYPTO_HMACMD5(ctx));
251 	if (rc) {
252 		ksmbd_debug(AUTH, "Could not init hmacmd5\n");
253 		goto out;
254 	}
255 
256 	len = CIFS_CRYPTO_KEY_SIZE + blen;
257 	construct = kzalloc(len, GFP_KERNEL);
258 	if (!construct) {
259 		rc = -ENOMEM;
260 		goto out;
261 	}
262 
263 	memcpy(construct, cryptkey, CIFS_CRYPTO_KEY_SIZE);
264 	memcpy(construct + CIFS_CRYPTO_KEY_SIZE, &ntlmv2->blob_signature, blen);
265 
266 	rc = crypto_shash_update(CRYPTO_HMACMD5(ctx), construct, len);
267 	if (rc) {
268 		ksmbd_debug(AUTH, "Could not update with response\n");
269 		goto out;
270 	}
271 
272 	rc = crypto_shash_final(CRYPTO_HMACMD5(ctx), ntlmv2_rsp);
273 	if (rc) {
274 		ksmbd_debug(AUTH, "Could not generate md5 hash\n");
275 		goto out;
276 	}
277 	ksmbd_release_crypto_ctx(ctx);
278 	ctx = NULL;
279 
280 	rc = ksmbd_gen_sess_key(sess, ntlmv2_hash, ntlmv2_rsp);
281 	if (rc) {
282 		ksmbd_debug(AUTH, "Could not generate sess key\n");
283 		goto out;
284 	}
285 
286 	if (memcmp(ntlmv2->ntlmv2_hash, ntlmv2_rsp, CIFS_HMAC_MD5_HASH_SIZE) != 0)
287 		rc = -EINVAL;
288 out:
289 	if (ctx)
290 		ksmbd_release_crypto_ctx(ctx);
291 	kfree(construct);
292 	return rc;
293 }
294 
295 /**
296  * ksmbd_decode_ntlmssp_auth_blob() - helper function to construct
297  * authenticate blob
298  * @authblob:	authenticate blob source pointer
299  * @blob_len:	length of the @authblob message
300  * @conn:	connection
301  * @sess:	session of connection
302  *
303  * Return:	0 on success, error number on error
304  */
305 int ksmbd_decode_ntlmssp_auth_blob(struct authenticate_message *authblob,
306 				   int blob_len, struct ksmbd_conn *conn,
307 				   struct ksmbd_session *sess)
308 {
309 	char *domain_name;
310 	unsigned int nt_off, dn_off;
311 	unsigned short nt_len, dn_len;
312 	int ret;
313 
314 	if (blob_len < sizeof(struct authenticate_message)) {
315 		ksmbd_debug(AUTH, "negotiate blob len %d too small\n",
316 			    blob_len);
317 		return -EINVAL;
318 	}
319 
320 	if (memcmp(authblob->Signature, "NTLMSSP", 8)) {
321 		ksmbd_debug(AUTH, "blob signature incorrect %s\n",
322 			    authblob->Signature);
323 		return -EINVAL;
324 	}
325 
326 	nt_off = le32_to_cpu(authblob->NtChallengeResponse.BufferOffset);
327 	nt_len = le16_to_cpu(authblob->NtChallengeResponse.Length);
328 	dn_off = le32_to_cpu(authblob->DomainName.BufferOffset);
329 	dn_len = le16_to_cpu(authblob->DomainName.Length);
330 
331 	if (blob_len < (u64)dn_off + dn_len || blob_len < (u64)nt_off + nt_len ||
332 	    nt_len < CIFS_ENCPWD_SIZE)
333 		return -EINVAL;
334 
335 	/* TODO : use domain name that imported from configuration file */
336 	domain_name = smb_strndup_from_utf16((const char *)authblob + dn_off,
337 					     dn_len, true, conn->local_nls);
338 	if (IS_ERR(domain_name))
339 		return PTR_ERR(domain_name);
340 
341 	/* process NTLMv2 authentication */
342 	ksmbd_debug(AUTH, "decode_ntlmssp_authenticate_blob dname%s\n",
343 		    domain_name);
344 	ret = ksmbd_auth_ntlmv2(conn, sess,
345 				(struct ntlmv2_resp *)((char *)authblob + nt_off),
346 				nt_len - CIFS_ENCPWD_SIZE,
347 				domain_name, conn->ntlmssp.cryptkey);
348 	kfree(domain_name);
349 
350 	/* The recovered secondary session key */
351 	if (conn->ntlmssp.client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) {
352 		struct arc4_ctx *ctx_arc4;
353 		unsigned int sess_key_off, sess_key_len;
354 
355 		sess_key_off = le32_to_cpu(authblob->SessionKey.BufferOffset);
356 		sess_key_len = le16_to_cpu(authblob->SessionKey.Length);
357 
358 		if (blob_len < (u64)sess_key_off + sess_key_len)
359 			return -EINVAL;
360 
361 		if (sess_key_len > CIFS_KEY_SIZE)
362 			return -EINVAL;
363 
364 		ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL);
365 		if (!ctx_arc4)
366 			return -ENOMEM;
367 
368 		cifs_arc4_setkey(ctx_arc4, sess->sess_key,
369 				 SMB2_NTLMV2_SESSKEY_SIZE);
370 		cifs_arc4_crypt(ctx_arc4, sess->sess_key,
371 				(char *)authblob + sess_key_off, sess_key_len);
372 		kfree_sensitive(ctx_arc4);
373 	}
374 
375 	return ret;
376 }
377 
378 /**
379  * ksmbd_decode_ntlmssp_neg_blob() - helper function to construct
380  * negotiate blob
381  * @negblob: negotiate blob source pointer
382  * @blob_len:	length of the @authblob message
383  * @conn:	connection
384  *
385  */
386 int ksmbd_decode_ntlmssp_neg_blob(struct negotiate_message *negblob,
387 				  int blob_len, struct ksmbd_conn *conn)
388 {
389 	if (blob_len < sizeof(struct negotiate_message)) {
390 		ksmbd_debug(AUTH, "negotiate blob len %d too small\n",
391 			    blob_len);
392 		return -EINVAL;
393 	}
394 
395 	if (memcmp(negblob->Signature, "NTLMSSP", 8)) {
396 		ksmbd_debug(AUTH, "blob signature incorrect %s\n",
397 			    negblob->Signature);
398 		return -EINVAL;
399 	}
400 
401 	conn->ntlmssp.client_flags = le32_to_cpu(negblob->NegotiateFlags);
402 	return 0;
403 }
404 
405 /**
406  * ksmbd_build_ntlmssp_challenge_blob() - helper function to construct
407  * challenge blob
408  * @chgblob: challenge blob source pointer to initialize
409  * @conn:	connection
410  *
411  */
412 unsigned int
413 ksmbd_build_ntlmssp_challenge_blob(struct challenge_message *chgblob,
414 				   struct ksmbd_conn *conn)
415 {
416 	struct target_info *tinfo;
417 	wchar_t *name;
418 	__u8 *target_name;
419 	unsigned int flags, blob_off, blob_len, type, target_info_len = 0;
420 	int len, uni_len, conv_len;
421 	int cflags = conn->ntlmssp.client_flags;
422 
423 	memcpy(chgblob->Signature, NTLMSSP_SIGNATURE, 8);
424 	chgblob->MessageType = NtLmChallenge;
425 
426 	flags = NTLMSSP_NEGOTIATE_UNICODE |
427 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_TARGET_TYPE_SERVER |
428 		NTLMSSP_NEGOTIATE_TARGET_INFO;
429 
430 	if (cflags & NTLMSSP_NEGOTIATE_SIGN) {
431 		flags |= NTLMSSP_NEGOTIATE_SIGN;
432 		flags |= cflags & (NTLMSSP_NEGOTIATE_128 |
433 				   NTLMSSP_NEGOTIATE_56);
434 	}
435 
436 	if (cflags & NTLMSSP_NEGOTIATE_SEAL && smb3_encryption_negotiated(conn))
437 		flags |= NTLMSSP_NEGOTIATE_SEAL;
438 
439 	if (cflags & NTLMSSP_NEGOTIATE_ALWAYS_SIGN)
440 		flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
441 
442 	if (cflags & NTLMSSP_REQUEST_TARGET)
443 		flags |= NTLMSSP_REQUEST_TARGET;
444 
445 	if (conn->use_spnego &&
446 	    (cflags & NTLMSSP_NEGOTIATE_EXTENDED_SEC))
447 		flags |= NTLMSSP_NEGOTIATE_EXTENDED_SEC;
448 
449 	if (cflags & NTLMSSP_NEGOTIATE_KEY_XCH)
450 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
451 
452 	chgblob->NegotiateFlags = cpu_to_le32(flags);
453 	len = strlen(ksmbd_netbios_name());
454 	name = kmalloc(2 + UNICODE_LEN(len), GFP_KERNEL);
455 	if (!name)
456 		return -ENOMEM;
457 
458 	conv_len = smb_strtoUTF16((__le16 *)name, ksmbd_netbios_name(), len,
459 				  conn->local_nls);
460 	if (conv_len < 0 || conv_len > len) {
461 		kfree(name);
462 		return -EINVAL;
463 	}
464 
465 	uni_len = UNICODE_LEN(conv_len);
466 
467 	blob_off = sizeof(struct challenge_message);
468 	blob_len = blob_off + uni_len;
469 
470 	chgblob->TargetName.Length = cpu_to_le16(uni_len);
471 	chgblob->TargetName.MaximumLength = cpu_to_le16(uni_len);
472 	chgblob->TargetName.BufferOffset = cpu_to_le32(blob_off);
473 
474 	/* Initialize random conn challenge */
475 	get_random_bytes(conn->ntlmssp.cryptkey, sizeof(__u64));
476 	memcpy(chgblob->Challenge, conn->ntlmssp.cryptkey,
477 	       CIFS_CRYPTO_KEY_SIZE);
478 
479 	/* Add Target Information to security buffer */
480 	chgblob->TargetInfoArray.BufferOffset = cpu_to_le32(blob_len);
481 
482 	target_name = (__u8 *)chgblob + blob_off;
483 	memcpy(target_name, name, uni_len);
484 	tinfo = (struct target_info *)(target_name + uni_len);
485 
486 	chgblob->TargetInfoArray.Length = 0;
487 	/* Add target info list for NetBIOS/DNS settings */
488 	for (type = NTLMSSP_AV_NB_COMPUTER_NAME;
489 	     type <= NTLMSSP_AV_DNS_DOMAIN_NAME; type++) {
490 		tinfo->Type = cpu_to_le16(type);
491 		tinfo->Length = cpu_to_le16(uni_len);
492 		memcpy(tinfo->Content, name, uni_len);
493 		tinfo = (struct target_info *)((char *)tinfo + 4 + uni_len);
494 		target_info_len += 4 + uni_len;
495 	}
496 
497 	/* Add terminator subblock */
498 	tinfo->Type = 0;
499 	tinfo->Length = 0;
500 	target_info_len += 4;
501 
502 	chgblob->TargetInfoArray.Length = cpu_to_le16(target_info_len);
503 	chgblob->TargetInfoArray.MaximumLength = cpu_to_le16(target_info_len);
504 	blob_len += target_info_len;
505 	kfree(name);
506 	ksmbd_debug(AUTH, "NTLMSSP SecurityBufferLength %d\n", blob_len);
507 	return blob_len;
508 }
509 
510 #ifdef CONFIG_SMB_SERVER_KERBEROS5
511 int ksmbd_krb5_authenticate(struct ksmbd_session *sess, char *in_blob,
512 			    int in_len, char *out_blob, int *out_len)
513 {
514 	struct ksmbd_spnego_authen_response *resp;
515 	struct ksmbd_user *user = NULL;
516 	int retval;
517 
518 	resp = ksmbd_ipc_spnego_authen_request(in_blob, in_len);
519 	if (!resp) {
520 		ksmbd_debug(AUTH, "SPNEGO_AUTHEN_REQUEST failure\n");
521 		return -EINVAL;
522 	}
523 
524 	if (!(resp->login_response.status & KSMBD_USER_FLAG_OK)) {
525 		ksmbd_debug(AUTH, "krb5 authentication failure\n");
526 		retval = -EPERM;
527 		goto out;
528 	}
529 
530 	if (*out_len <= resp->spnego_blob_len) {
531 		ksmbd_debug(AUTH, "buf len %d, but blob len %d\n",
532 			    *out_len, resp->spnego_blob_len);
533 		retval = -EINVAL;
534 		goto out;
535 	}
536 
537 	if (resp->session_key_len > sizeof(sess->sess_key)) {
538 		ksmbd_debug(AUTH, "session key is too long\n");
539 		retval = -EINVAL;
540 		goto out;
541 	}
542 
543 	user = ksmbd_alloc_user(&resp->login_response);
544 	if (!user) {
545 		ksmbd_debug(AUTH, "login failure\n");
546 		retval = -ENOMEM;
547 		goto out;
548 	}
549 	sess->user = user;
550 
551 	memcpy(sess->sess_key, resp->payload, resp->session_key_len);
552 	memcpy(out_blob, resp->payload + resp->session_key_len,
553 	       resp->spnego_blob_len);
554 	*out_len = resp->spnego_blob_len;
555 	retval = 0;
556 out:
557 	kvfree(resp);
558 	return retval;
559 }
560 #else
561 int ksmbd_krb5_authenticate(struct ksmbd_session *sess, char *in_blob,
562 			    int in_len, char *out_blob, int *out_len)
563 {
564 	return -EOPNOTSUPP;
565 }
566 #endif
567 
568 /**
569  * ksmbd_sign_smb2_pdu() - function to generate packet signing
570  * @conn:	connection
571  * @key:	signing key
572  * @iov:        buffer iov array
573  * @n_vec:	number of iovecs
574  * @sig:	signature value generated for client request packet
575  *
576  */
577 int ksmbd_sign_smb2_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
578 			int n_vec, char *sig)
579 {
580 	struct ksmbd_crypto_ctx *ctx;
581 	int rc, i;
582 
583 	ctx = ksmbd_crypto_ctx_find_hmacsha256();
584 	if (!ctx) {
585 		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
586 		return -ENOMEM;
587 	}
588 
589 	rc = crypto_shash_setkey(CRYPTO_HMACSHA256_TFM(ctx),
590 				 key,
591 				 SMB2_NTLMV2_SESSKEY_SIZE);
592 	if (rc)
593 		goto out;
594 
595 	rc = crypto_shash_init(CRYPTO_HMACSHA256(ctx));
596 	if (rc) {
597 		ksmbd_debug(AUTH, "hmacsha256 init error %d\n", rc);
598 		goto out;
599 	}
600 
601 	for (i = 0; i < n_vec; i++) {
602 		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
603 					 iov[i].iov_base,
604 					 iov[i].iov_len);
605 		if (rc) {
606 			ksmbd_debug(AUTH, "hmacsha256 update error %d\n", rc);
607 			goto out;
608 		}
609 	}
610 
611 	rc = crypto_shash_final(CRYPTO_HMACSHA256(ctx), sig);
612 	if (rc)
613 		ksmbd_debug(AUTH, "hmacsha256 generation error %d\n", rc);
614 out:
615 	ksmbd_release_crypto_ctx(ctx);
616 	return rc;
617 }
618 
619 /**
620  * ksmbd_sign_smb3_pdu() - function to generate packet signing
621  * @conn:	connection
622  * @key:	signing key
623  * @iov:        buffer iov array
624  * @n_vec:	number of iovecs
625  * @sig:	signature value generated for client request packet
626  *
627  */
628 int ksmbd_sign_smb3_pdu(struct ksmbd_conn *conn, char *key, struct kvec *iov,
629 			int n_vec, char *sig)
630 {
631 	struct ksmbd_crypto_ctx *ctx;
632 	int rc, i;
633 
634 	ctx = ksmbd_crypto_ctx_find_cmacaes();
635 	if (!ctx) {
636 		ksmbd_debug(AUTH, "could not crypto alloc cmac\n");
637 		return -ENOMEM;
638 	}
639 
640 	rc = crypto_shash_setkey(CRYPTO_CMACAES_TFM(ctx),
641 				 key,
642 				 SMB2_CMACAES_SIZE);
643 	if (rc)
644 		goto out;
645 
646 	rc = crypto_shash_init(CRYPTO_CMACAES(ctx));
647 	if (rc) {
648 		ksmbd_debug(AUTH, "cmaces init error %d\n", rc);
649 		goto out;
650 	}
651 
652 	for (i = 0; i < n_vec; i++) {
653 		rc = crypto_shash_update(CRYPTO_CMACAES(ctx),
654 					 iov[i].iov_base,
655 					 iov[i].iov_len);
656 		if (rc) {
657 			ksmbd_debug(AUTH, "cmaces update error %d\n", rc);
658 			goto out;
659 		}
660 	}
661 
662 	rc = crypto_shash_final(CRYPTO_CMACAES(ctx), sig);
663 	if (rc)
664 		ksmbd_debug(AUTH, "cmaces generation error %d\n", rc);
665 out:
666 	ksmbd_release_crypto_ctx(ctx);
667 	return rc;
668 }
669 
670 struct derivation {
671 	struct kvec label;
672 	struct kvec context;
673 	bool binding;
674 };
675 
676 static int generate_key(struct ksmbd_conn *conn, struct ksmbd_session *sess,
677 			struct kvec label, struct kvec context, __u8 *key,
678 			unsigned int key_size)
679 {
680 	unsigned char zero = 0x0;
681 	__u8 i[4] = {0, 0, 0, 1};
682 	__u8 L128[4] = {0, 0, 0, 128};
683 	__u8 L256[4] = {0, 0, 1, 0};
684 	int rc;
685 	unsigned char prfhash[SMB2_HMACSHA256_SIZE];
686 	unsigned char *hashptr = prfhash;
687 	struct ksmbd_crypto_ctx *ctx;
688 
689 	memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
690 	memset(key, 0x0, key_size);
691 
692 	ctx = ksmbd_crypto_ctx_find_hmacsha256();
693 	if (!ctx) {
694 		ksmbd_debug(AUTH, "could not crypto alloc hmacmd5\n");
695 		return -ENOMEM;
696 	}
697 
698 	rc = crypto_shash_setkey(CRYPTO_HMACSHA256_TFM(ctx),
699 				 sess->sess_key,
700 				 SMB2_NTLMV2_SESSKEY_SIZE);
701 	if (rc)
702 		goto smb3signkey_ret;
703 
704 	rc = crypto_shash_init(CRYPTO_HMACSHA256(ctx));
705 	if (rc) {
706 		ksmbd_debug(AUTH, "hmacsha256 init error %d\n", rc);
707 		goto smb3signkey_ret;
708 	}
709 
710 	rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), i, 4);
711 	if (rc) {
712 		ksmbd_debug(AUTH, "could not update with n\n");
713 		goto smb3signkey_ret;
714 	}
715 
716 	rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
717 				 label.iov_base,
718 				 label.iov_len);
719 	if (rc) {
720 		ksmbd_debug(AUTH, "could not update with label\n");
721 		goto smb3signkey_ret;
722 	}
723 
724 	rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), &zero, 1);
725 	if (rc) {
726 		ksmbd_debug(AUTH, "could not update with zero\n");
727 		goto smb3signkey_ret;
728 	}
729 
730 	rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx),
731 				 context.iov_base,
732 				 context.iov_len);
733 	if (rc) {
734 		ksmbd_debug(AUTH, "could not update with context\n");
735 		goto smb3signkey_ret;
736 	}
737 
738 	if (key_size == SMB3_ENC_DEC_KEY_SIZE &&
739 	    (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
740 	     conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
741 		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L256, 4);
742 	else
743 		rc = crypto_shash_update(CRYPTO_HMACSHA256(ctx), L128, 4);
744 	if (rc) {
745 		ksmbd_debug(AUTH, "could not update with L\n");
746 		goto smb3signkey_ret;
747 	}
748 
749 	rc = crypto_shash_final(CRYPTO_HMACSHA256(ctx), hashptr);
750 	if (rc) {
751 		ksmbd_debug(AUTH, "Could not generate hmacmd5 hash error %d\n",
752 			    rc);
753 		goto smb3signkey_ret;
754 	}
755 
756 	memcpy(key, hashptr, key_size);
757 
758 smb3signkey_ret:
759 	ksmbd_release_crypto_ctx(ctx);
760 	return rc;
761 }
762 
763 static int generate_smb3signingkey(struct ksmbd_session *sess,
764 				   struct ksmbd_conn *conn,
765 				   const struct derivation *signing)
766 {
767 	int rc;
768 	struct channel *chann;
769 	char *key;
770 
771 	chann = lookup_chann_list(sess, conn);
772 	if (!chann)
773 		return 0;
774 
775 	if (conn->dialect >= SMB30_PROT_ID && signing->binding)
776 		key = chann->smb3signingkey;
777 	else
778 		key = sess->smb3signingkey;
779 
780 	rc = generate_key(conn, sess, signing->label, signing->context, key,
781 			  SMB3_SIGN_KEY_SIZE);
782 	if (rc)
783 		return rc;
784 
785 	if (!(conn->dialect >= SMB30_PROT_ID && signing->binding))
786 		memcpy(chann->smb3signingkey, key, SMB3_SIGN_KEY_SIZE);
787 
788 	ksmbd_debug(AUTH, "dumping generated AES signing keys\n");
789 	ksmbd_debug(AUTH, "Session Id    %llu\n", sess->id);
790 	ksmbd_debug(AUTH, "Session Key   %*ph\n",
791 		    SMB2_NTLMV2_SESSKEY_SIZE, sess->sess_key);
792 	ksmbd_debug(AUTH, "Signing Key   %*ph\n",
793 		    SMB3_SIGN_KEY_SIZE, key);
794 	return 0;
795 }
796 
797 int ksmbd_gen_smb30_signingkey(struct ksmbd_session *sess,
798 			       struct ksmbd_conn *conn)
799 {
800 	struct derivation d;
801 
802 	d.label.iov_base = "SMB2AESCMAC";
803 	d.label.iov_len = 12;
804 	d.context.iov_base = "SmbSign";
805 	d.context.iov_len = 8;
806 	d.binding = conn->binding;
807 
808 	return generate_smb3signingkey(sess, conn, &d);
809 }
810 
811 int ksmbd_gen_smb311_signingkey(struct ksmbd_session *sess,
812 				struct ksmbd_conn *conn)
813 {
814 	struct derivation d;
815 
816 	d.label.iov_base = "SMBSigningKey";
817 	d.label.iov_len = 14;
818 	if (conn->binding) {
819 		struct preauth_session *preauth_sess;
820 
821 		preauth_sess = ksmbd_preauth_session_lookup(conn, sess->id);
822 		if (!preauth_sess)
823 			return -ENOENT;
824 		d.context.iov_base = preauth_sess->Preauth_HashValue;
825 	} else {
826 		d.context.iov_base = sess->Preauth_HashValue;
827 	}
828 	d.context.iov_len = 64;
829 	d.binding = conn->binding;
830 
831 	return generate_smb3signingkey(sess, conn, &d);
832 }
833 
834 struct derivation_twin {
835 	struct derivation encryption;
836 	struct derivation decryption;
837 };
838 
839 static int generate_smb3encryptionkey(struct ksmbd_conn *conn,
840 				      struct ksmbd_session *sess,
841 				      const struct derivation_twin *ptwin)
842 {
843 	int rc;
844 
845 	rc = generate_key(conn, sess, ptwin->encryption.label,
846 			  ptwin->encryption.context, sess->smb3encryptionkey,
847 			  SMB3_ENC_DEC_KEY_SIZE);
848 	if (rc)
849 		return rc;
850 
851 	rc = generate_key(conn, sess, ptwin->decryption.label,
852 			  ptwin->decryption.context,
853 			  sess->smb3decryptionkey, SMB3_ENC_DEC_KEY_SIZE);
854 	if (rc)
855 		return rc;
856 
857 	ksmbd_debug(AUTH, "dumping generated AES encryption keys\n");
858 	ksmbd_debug(AUTH, "Cipher type   %d\n", conn->cipher_type);
859 	ksmbd_debug(AUTH, "Session Id    %llu\n", sess->id);
860 	ksmbd_debug(AUTH, "Session Key   %*ph\n",
861 		    SMB2_NTLMV2_SESSKEY_SIZE, sess->sess_key);
862 	if (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
863 	    conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM) {
864 		ksmbd_debug(AUTH, "ServerIn Key  %*ph\n",
865 			    SMB3_GCM256_CRYPTKEY_SIZE, sess->smb3encryptionkey);
866 		ksmbd_debug(AUTH, "ServerOut Key %*ph\n",
867 			    SMB3_GCM256_CRYPTKEY_SIZE, sess->smb3decryptionkey);
868 	} else {
869 		ksmbd_debug(AUTH, "ServerIn Key  %*ph\n",
870 			    SMB3_GCM128_CRYPTKEY_SIZE, sess->smb3encryptionkey);
871 		ksmbd_debug(AUTH, "ServerOut Key %*ph\n",
872 			    SMB3_GCM128_CRYPTKEY_SIZE, sess->smb3decryptionkey);
873 	}
874 	return 0;
875 }
876 
877 int ksmbd_gen_smb30_encryptionkey(struct ksmbd_conn *conn,
878 				  struct ksmbd_session *sess)
879 {
880 	struct derivation_twin twin;
881 	struct derivation *d;
882 
883 	d = &twin.encryption;
884 	d->label.iov_base = "SMB2AESCCM";
885 	d->label.iov_len = 11;
886 	d->context.iov_base = "ServerOut";
887 	d->context.iov_len = 10;
888 
889 	d = &twin.decryption;
890 	d->label.iov_base = "SMB2AESCCM";
891 	d->label.iov_len = 11;
892 	d->context.iov_base = "ServerIn ";
893 	d->context.iov_len = 10;
894 
895 	return generate_smb3encryptionkey(conn, sess, &twin);
896 }
897 
898 int ksmbd_gen_smb311_encryptionkey(struct ksmbd_conn *conn,
899 				   struct ksmbd_session *sess)
900 {
901 	struct derivation_twin twin;
902 	struct derivation *d;
903 
904 	d = &twin.encryption;
905 	d->label.iov_base = "SMBS2CCipherKey";
906 	d->label.iov_len = 16;
907 	d->context.iov_base = sess->Preauth_HashValue;
908 	d->context.iov_len = 64;
909 
910 	d = &twin.decryption;
911 	d->label.iov_base = "SMBC2SCipherKey";
912 	d->label.iov_len = 16;
913 	d->context.iov_base = sess->Preauth_HashValue;
914 	d->context.iov_len = 64;
915 
916 	return generate_smb3encryptionkey(conn, sess, &twin);
917 }
918 
919 int ksmbd_gen_preauth_integrity_hash(struct ksmbd_conn *conn, char *buf,
920 				     __u8 *pi_hash)
921 {
922 	int rc;
923 	struct smb2_hdr *rcv_hdr = smb2_get_msg(buf);
924 	char *all_bytes_msg = (char *)&rcv_hdr->ProtocolId;
925 	int msg_size = get_rfc1002_len(buf);
926 	struct ksmbd_crypto_ctx *ctx = NULL;
927 
928 	if (conn->preauth_info->Preauth_HashId !=
929 	    SMB2_PREAUTH_INTEGRITY_SHA512)
930 		return -EINVAL;
931 
932 	ctx = ksmbd_crypto_ctx_find_sha512();
933 	if (!ctx) {
934 		ksmbd_debug(AUTH, "could not alloc sha512\n");
935 		return -ENOMEM;
936 	}
937 
938 	rc = crypto_shash_init(CRYPTO_SHA512(ctx));
939 	if (rc) {
940 		ksmbd_debug(AUTH, "could not init shashn");
941 		goto out;
942 	}
943 
944 	rc = crypto_shash_update(CRYPTO_SHA512(ctx), pi_hash, 64);
945 	if (rc) {
946 		ksmbd_debug(AUTH, "could not update with n\n");
947 		goto out;
948 	}
949 
950 	rc = crypto_shash_update(CRYPTO_SHA512(ctx), all_bytes_msg, msg_size);
951 	if (rc) {
952 		ksmbd_debug(AUTH, "could not update with n\n");
953 		goto out;
954 	}
955 
956 	rc = crypto_shash_final(CRYPTO_SHA512(ctx), pi_hash);
957 	if (rc) {
958 		ksmbd_debug(AUTH, "Could not generate hash err : %d\n", rc);
959 		goto out;
960 	}
961 out:
962 	ksmbd_release_crypto_ctx(ctx);
963 	return rc;
964 }
965 
966 int ksmbd_gen_sd_hash(struct ksmbd_conn *conn, char *sd_buf, int len,
967 		      __u8 *pi_hash)
968 {
969 	int rc;
970 	struct ksmbd_crypto_ctx *ctx = NULL;
971 
972 	ctx = ksmbd_crypto_ctx_find_sha256();
973 	if (!ctx) {
974 		ksmbd_debug(AUTH, "could not alloc sha256\n");
975 		return -ENOMEM;
976 	}
977 
978 	rc = crypto_shash_init(CRYPTO_SHA256(ctx));
979 	if (rc) {
980 		ksmbd_debug(AUTH, "could not init shashn");
981 		goto out;
982 	}
983 
984 	rc = crypto_shash_update(CRYPTO_SHA256(ctx), sd_buf, len);
985 	if (rc) {
986 		ksmbd_debug(AUTH, "could not update with n\n");
987 		goto out;
988 	}
989 
990 	rc = crypto_shash_final(CRYPTO_SHA256(ctx), pi_hash);
991 	if (rc) {
992 		ksmbd_debug(AUTH, "Could not generate hash err : %d\n", rc);
993 		goto out;
994 	}
995 out:
996 	ksmbd_release_crypto_ctx(ctx);
997 	return rc;
998 }
999 
1000 static int ksmbd_get_encryption_key(struct ksmbd_work *work, __u64 ses_id,
1001 				    int enc, u8 *key)
1002 {
1003 	struct ksmbd_session *sess;
1004 	u8 *ses_enc_key;
1005 
1006 	if (enc)
1007 		sess = work->sess;
1008 	else
1009 		sess = ksmbd_session_lookup_all(work->conn, ses_id);
1010 	if (!sess)
1011 		return -EINVAL;
1012 
1013 	ses_enc_key = enc ? sess->smb3encryptionkey :
1014 		sess->smb3decryptionkey;
1015 	memcpy(key, ses_enc_key, SMB3_ENC_DEC_KEY_SIZE);
1016 
1017 	return 0;
1018 }
1019 
1020 static inline void smb2_sg_set_buf(struct scatterlist *sg, const void *buf,
1021 				   unsigned int buflen)
1022 {
1023 	void *addr;
1024 
1025 	if (is_vmalloc_addr(buf))
1026 		addr = vmalloc_to_page(buf);
1027 	else
1028 		addr = virt_to_page(buf);
1029 	sg_set_page(sg, addr, buflen, offset_in_page(buf));
1030 }
1031 
1032 static struct scatterlist *ksmbd_init_sg(struct kvec *iov, unsigned int nvec,
1033 					 u8 *sign)
1034 {
1035 	struct scatterlist *sg;
1036 	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
1037 	int i, *nr_entries, total_entries = 0, sg_idx = 0;
1038 
1039 	if (!nvec)
1040 		return NULL;
1041 
1042 	nr_entries = kcalloc(nvec, sizeof(int), GFP_KERNEL);
1043 	if (!nr_entries)
1044 		return NULL;
1045 
1046 	for (i = 0; i < nvec - 1; i++) {
1047 		unsigned long kaddr = (unsigned long)iov[i + 1].iov_base;
1048 
1049 		if (is_vmalloc_addr(iov[i + 1].iov_base)) {
1050 			nr_entries[i] = ((kaddr + iov[i + 1].iov_len +
1051 					PAGE_SIZE - 1) >> PAGE_SHIFT) -
1052 				(kaddr >> PAGE_SHIFT);
1053 		} else {
1054 			nr_entries[i]++;
1055 		}
1056 		total_entries += nr_entries[i];
1057 	}
1058 
1059 	/* Add two entries for transform header and signature */
1060 	total_entries += 2;
1061 
1062 	sg = kmalloc_array(total_entries, sizeof(struct scatterlist), GFP_KERNEL);
1063 	if (!sg) {
1064 		kfree(nr_entries);
1065 		return NULL;
1066 	}
1067 
1068 	sg_init_table(sg, total_entries);
1069 	smb2_sg_set_buf(&sg[sg_idx++], iov[0].iov_base + 24, assoc_data_len);
1070 	for (i = 0; i < nvec - 1; i++) {
1071 		void *data = iov[i + 1].iov_base;
1072 		int len = iov[i + 1].iov_len;
1073 
1074 		if (is_vmalloc_addr(data)) {
1075 			int j, offset = offset_in_page(data);
1076 
1077 			for (j = 0; j < nr_entries[i]; j++) {
1078 				unsigned int bytes = PAGE_SIZE - offset;
1079 
1080 				if (!len)
1081 					break;
1082 
1083 				if (bytes > len)
1084 					bytes = len;
1085 
1086 				sg_set_page(&sg[sg_idx++],
1087 					    vmalloc_to_page(data), bytes,
1088 					    offset_in_page(data));
1089 
1090 				data += bytes;
1091 				len -= bytes;
1092 				offset = 0;
1093 			}
1094 		} else {
1095 			sg_set_page(&sg[sg_idx++], virt_to_page(data), len,
1096 				    offset_in_page(data));
1097 		}
1098 	}
1099 	smb2_sg_set_buf(&sg[sg_idx], sign, SMB2_SIGNATURE_SIZE);
1100 	kfree(nr_entries);
1101 	return sg;
1102 }
1103 
1104 int ksmbd_crypt_message(struct ksmbd_work *work, struct kvec *iov,
1105 			unsigned int nvec, int enc)
1106 {
1107 	struct ksmbd_conn *conn = work->conn;
1108 	struct smb2_transform_hdr *tr_hdr = smb2_get_msg(iov[0].iov_base);
1109 	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
1110 	int rc;
1111 	struct scatterlist *sg;
1112 	u8 sign[SMB2_SIGNATURE_SIZE] = {};
1113 	u8 key[SMB3_ENC_DEC_KEY_SIZE];
1114 	struct aead_request *req;
1115 	char *iv;
1116 	unsigned int iv_len;
1117 	struct crypto_aead *tfm;
1118 	unsigned int crypt_len = le32_to_cpu(tr_hdr->OriginalMessageSize);
1119 	struct ksmbd_crypto_ctx *ctx;
1120 
1121 	rc = ksmbd_get_encryption_key(work,
1122 				      le64_to_cpu(tr_hdr->SessionId),
1123 				      enc,
1124 				      key);
1125 	if (rc) {
1126 		pr_err("Could not get %scryption key\n", enc ? "en" : "de");
1127 		return rc;
1128 	}
1129 
1130 	if (conn->cipher_type == SMB2_ENCRYPTION_AES128_GCM ||
1131 	    conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
1132 		ctx = ksmbd_crypto_ctx_find_gcm();
1133 	else
1134 		ctx = ksmbd_crypto_ctx_find_ccm();
1135 	if (!ctx) {
1136 		pr_err("crypto alloc failed\n");
1137 		return -ENOMEM;
1138 	}
1139 
1140 	if (conn->cipher_type == SMB2_ENCRYPTION_AES128_GCM ||
1141 	    conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
1142 		tfm = CRYPTO_GCM(ctx);
1143 	else
1144 		tfm = CRYPTO_CCM(ctx);
1145 
1146 	if (conn->cipher_type == SMB2_ENCRYPTION_AES256_CCM ||
1147 	    conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM)
1148 		rc = crypto_aead_setkey(tfm, key, SMB3_GCM256_CRYPTKEY_SIZE);
1149 	else
1150 		rc = crypto_aead_setkey(tfm, key, SMB3_GCM128_CRYPTKEY_SIZE);
1151 	if (rc) {
1152 		pr_err("Failed to set aead key %d\n", rc);
1153 		goto free_ctx;
1154 	}
1155 
1156 	rc = crypto_aead_setauthsize(tfm, SMB2_SIGNATURE_SIZE);
1157 	if (rc) {
1158 		pr_err("Failed to set authsize %d\n", rc);
1159 		goto free_ctx;
1160 	}
1161 
1162 	req = aead_request_alloc(tfm, GFP_KERNEL);
1163 	if (!req) {
1164 		rc = -ENOMEM;
1165 		goto free_ctx;
1166 	}
1167 
1168 	if (!enc) {
1169 		memcpy(sign, &tr_hdr->Signature, SMB2_SIGNATURE_SIZE);
1170 		crypt_len += SMB2_SIGNATURE_SIZE;
1171 	}
1172 
1173 	sg = ksmbd_init_sg(iov, nvec, sign);
1174 	if (!sg) {
1175 		pr_err("Failed to init sg\n");
1176 		rc = -ENOMEM;
1177 		goto free_req;
1178 	}
1179 
1180 	iv_len = crypto_aead_ivsize(tfm);
1181 	iv = kzalloc(iv_len, GFP_KERNEL);
1182 	if (!iv) {
1183 		rc = -ENOMEM;
1184 		goto free_sg;
1185 	}
1186 
1187 	if (conn->cipher_type == SMB2_ENCRYPTION_AES128_GCM ||
1188 	    conn->cipher_type == SMB2_ENCRYPTION_AES256_GCM) {
1189 		memcpy(iv, (char *)tr_hdr->Nonce, SMB3_AES_GCM_NONCE);
1190 	} else {
1191 		iv[0] = 3;
1192 		memcpy(iv + 1, (char *)tr_hdr->Nonce, SMB3_AES_CCM_NONCE);
1193 	}
1194 
1195 	aead_request_set_crypt(req, sg, sg, crypt_len, iv);
1196 	aead_request_set_ad(req, assoc_data_len);
1197 	aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
1198 
1199 	if (enc)
1200 		rc = crypto_aead_encrypt(req);
1201 	else
1202 		rc = crypto_aead_decrypt(req);
1203 	if (rc)
1204 		goto free_iv;
1205 
1206 	if (enc)
1207 		memcpy(&tr_hdr->Signature, sign, SMB2_SIGNATURE_SIZE);
1208 
1209 free_iv:
1210 	kfree(iv);
1211 free_sg:
1212 	kfree(sg);
1213 free_req:
1214 	kfree(req);
1215 free_ctx:
1216 	ksmbd_release_crypto_ctx(ctx);
1217 	return rc;
1218 }
1219