1 /*
2  *   fs/cifs/cifsencrypt.c
3  *
4  *   Copyright (C) International Business Machines  Corp., 2005,2006
5  *   Author(s): Steve French (sfrench@us.ibm.com)
6  *
7  *   This library is free software; you can redistribute it and/or modify
8  *   it under the terms of the GNU Lesser General Public License as published
9  *   by the Free Software Foundation; either version 2.1 of the License, or
10  *   (at your option) any later version.
11  *
12  *   This library is distributed in the hope that it will be useful,
13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
15  *   the GNU Lesser General Public License for more details.
16  *
17  *   You should have received a copy of the GNU Lesser General Public License
18  *   along with this library; if not, write to the Free Software
19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20  */
21 
22 #include <linux/fs.h>
23 #include <linux/slab.h>
24 #include "cifspdu.h"
25 #include "cifsglob.h"
26 #include "cifs_debug.h"
27 #include "cifs_unicode.h"
28 #include "cifsproto.h"
29 #include "ntlmssp.h"
30 #include <linux/ctype.h>
31 #include <linux/random.h>
32 
33 /*
34  * Calculate and return the CIFS signature based on the mac key and SMB PDU.
35  * The 16 byte signature must be allocated by the caller. Note we only use the
36  * 1st eight bytes and that the smb header signature field on input contains
37  * the sequence number before this function is called. Also, this function
38  * should be called with the server->srv_mutex held.
39  */
cifs_calc_signature(const struct kvec * iov,int n_vec,struct TCP_Server_Info * server,char * signature)40 static int cifs_calc_signature(const struct kvec *iov, int n_vec,
41 			struct TCP_Server_Info *server, char *signature)
42 {
43 	int i;
44 	int rc;
45 
46 	if (iov == NULL || signature == NULL || server == NULL)
47 		return -EINVAL;
48 
49 	if (!server->secmech.sdescmd5) {
50 		cERROR(1, "%s: Can't generate signature\n", __func__);
51 		return -1;
52 	}
53 
54 	rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
55 	if (rc) {
56 		cERROR(1, "%s: Could not init md5\n", __func__);
57 		return rc;
58 	}
59 
60 	rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
61 		server->session_key.response, server->session_key.len);
62 	if (rc) {
63 		cERROR(1, "%s: Could not update with response\n", __func__);
64 		return rc;
65 	}
66 
67 	for (i = 0; i < n_vec; i++) {
68 		if (iov[i].iov_len == 0)
69 			continue;
70 		if (iov[i].iov_base == NULL) {
71 			cERROR(1, "null iovec entry");
72 			return -EIO;
73 		}
74 		/* The first entry includes a length field (which does not get
75 		   signed that occupies the first 4 bytes before the header */
76 		if (i == 0) {
77 			if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
78 				break; /* nothing to sign or corrupt header */
79 			rc =
80 			crypto_shash_update(&server->secmech.sdescmd5->shash,
81 				iov[i].iov_base + 4, iov[i].iov_len - 4);
82 		} else {
83 			rc =
84 			crypto_shash_update(&server->secmech.sdescmd5->shash,
85 				iov[i].iov_base, iov[i].iov_len);
86 		}
87 		if (rc) {
88 			cERROR(1, "%s: Could not update with payload\n",
89 							__func__);
90 			return rc;
91 		}
92 	}
93 
94 	rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
95 	if (rc)
96 		cERROR(1, "%s: Could not generate md5 hash\n", __func__);
97 
98 	return rc;
99 }
100 
101 /* must be called with server->srv_mutex held */
cifs_sign_smb2(struct kvec * iov,int n_vec,struct TCP_Server_Info * server,__u32 * pexpected_response_sequence_number)102 int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
103 		   __u32 *pexpected_response_sequence_number)
104 {
105 	int rc = 0;
106 	char smb_signature[20];
107 	struct smb_hdr *cifs_pdu = (struct smb_hdr *)iov[0].iov_base;
108 
109 	if ((cifs_pdu == NULL) || (server == NULL))
110 		return -EINVAL;
111 
112 	if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
113 	    server->tcpStatus == CifsNeedNegotiate)
114 		return rc;
115 
116 	if (!server->session_estab) {
117 		memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
118 		return rc;
119 	}
120 
121 	cifs_pdu->Signature.Sequence.SequenceNumber =
122 				cpu_to_le32(server->sequence_number);
123 	cifs_pdu->Signature.Sequence.Reserved = 0;
124 
125 	*pexpected_response_sequence_number = server->sequence_number++;
126 	server->sequence_number++;
127 
128 	rc = cifs_calc_signature(iov, n_vec, server, smb_signature);
129 	if (rc)
130 		memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
131 	else
132 		memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
133 
134 	return rc;
135 }
136 
137 /* must be called with server->srv_mutex held */
cifs_sign_smb(struct smb_hdr * cifs_pdu,struct TCP_Server_Info * server,__u32 * pexpected_response_sequence_number)138 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
139 		  __u32 *pexpected_response_sequence_number)
140 {
141 	struct kvec iov;
142 
143 	iov.iov_base = cifs_pdu;
144 	iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
145 
146 	return cifs_sign_smb2(&iov, 1, server,
147 			      pexpected_response_sequence_number);
148 }
149 
cifs_verify_signature(struct kvec * iov,unsigned int nr_iov,struct TCP_Server_Info * server,__u32 expected_sequence_number)150 int cifs_verify_signature(struct kvec *iov, unsigned int nr_iov,
151 			  struct TCP_Server_Info *server,
152 			  __u32 expected_sequence_number)
153 {
154 	unsigned int rc;
155 	char server_response_sig[8];
156 	char what_we_think_sig_should_be[20];
157 	struct smb_hdr *cifs_pdu = (struct smb_hdr *)iov[0].iov_base;
158 
159 	if (cifs_pdu == NULL || server == NULL)
160 		return -EINVAL;
161 
162 	if (!server->session_estab)
163 		return 0;
164 
165 	if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
166 		struct smb_com_lock_req *pSMB =
167 			(struct smb_com_lock_req *)cifs_pdu;
168 	    if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
169 			return 0;
170 	}
171 
172 	/* BB what if signatures are supposed to be on for session but
173 	   server does not send one? BB */
174 
175 	/* Do not need to verify session setups with signature "BSRSPYL "  */
176 	if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
177 		cFYI(1, "dummy signature received for smb command 0x%x",
178 			cifs_pdu->Command);
179 
180 	/* save off the origiginal signature so we can modify the smb and check
181 		its signature against what the server sent */
182 	memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
183 
184 	cifs_pdu->Signature.Sequence.SequenceNumber =
185 					cpu_to_le32(expected_sequence_number);
186 	cifs_pdu->Signature.Sequence.Reserved = 0;
187 
188 	mutex_lock(&server->srv_mutex);
189 	rc = cifs_calc_signature(iov, nr_iov, server,
190 				 what_we_think_sig_should_be);
191 	mutex_unlock(&server->srv_mutex);
192 
193 	if (rc)
194 		return rc;
195 
196 /*	cifs_dump_mem("what we think it should be: ",
197 		      what_we_think_sig_should_be, 16); */
198 
199 	if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
200 		return -EACCES;
201 	else
202 		return 0;
203 
204 }
205 
206 /* first calculate 24 bytes ntlm response and then 16 byte session key */
setup_ntlm_response(struct cifs_ses * ses,const struct nls_table * nls_cp)207 int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
208 {
209 	int rc = 0;
210 	unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
211 	char temp_key[CIFS_SESS_KEY_SIZE];
212 
213 	if (!ses)
214 		return -EINVAL;
215 
216 	ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
217 	if (!ses->auth_key.response) {
218 		cERROR(1, "NTLM can't allocate (%u bytes) memory", temp_len);
219 		return -ENOMEM;
220 	}
221 	ses->auth_key.len = temp_len;
222 
223 	rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
224 			ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
225 	if (rc) {
226 		cFYI(1, "%s Can't generate NTLM response, error: %d",
227 			__func__, rc);
228 		return rc;
229 	}
230 
231 	rc = E_md4hash(ses->password, temp_key, nls_cp);
232 	if (rc) {
233 		cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
234 		return rc;
235 	}
236 
237 	rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
238 	if (rc)
239 		cFYI(1, "%s Can't generate NTLM session key, error: %d",
240 			__func__, rc);
241 
242 	return rc;
243 }
244 
245 #ifdef CONFIG_CIFS_WEAK_PW_HASH
calc_lanman_hash(const char * password,const char * cryptkey,bool encrypt,char * lnm_session_key)246 int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
247 			char *lnm_session_key)
248 {
249 	int i;
250 	int rc;
251 	char password_with_pad[CIFS_ENCPWD_SIZE];
252 
253 	memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
254 	if (password)
255 		strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
256 
257 	if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
258 		memset(lnm_session_key, 0, CIFS_SESS_KEY_SIZE);
259 		memcpy(lnm_session_key, password_with_pad,
260 			CIFS_ENCPWD_SIZE);
261 		return 0;
262 	}
263 
264 	/* calculate old style session key */
265 	/* calling toupper is less broken than repeatedly
266 	calling nls_toupper would be since that will never
267 	work for UTF8, but neither handles multibyte code pages
268 	but the only alternative would be converting to UCS-16 (Unicode)
269 	(using a routine something like UniStrupr) then
270 	uppercasing and then converting back from Unicode - which
271 	would only worth doing it if we knew it were utf8. Basically
272 	utf8 and other multibyte codepages each need their own strupper
273 	function since a byte at a time will ont work. */
274 
275 	for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
276 		password_with_pad[i] = toupper(password_with_pad[i]);
277 
278 	rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
279 
280 	return rc;
281 }
282 #endif /* CIFS_WEAK_PW_HASH */
283 
284 /* Build a proper attribute value/target info pairs blob.
285  * Fill in netbios and dns domain name and workstation name
286  * and client time (total five av pairs and + one end of fields indicator.
287  * Allocate domain name which gets freed when session struct is deallocated.
288  */
289 static int
build_avpair_blob(struct cifs_ses * ses,const struct nls_table * nls_cp)290 build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
291 {
292 	unsigned int dlen;
293 	unsigned int size = 2 * sizeof(struct ntlmssp2_name);
294 	char *defdmname = "WORKGROUP";
295 	unsigned char *blobptr;
296 	struct ntlmssp2_name *attrptr;
297 
298 	if (!ses->domainName) {
299 		ses->domainName = kstrdup(defdmname, GFP_KERNEL);
300 		if (!ses->domainName)
301 			return -ENOMEM;
302 	}
303 
304 	dlen = strlen(ses->domainName);
305 
306 	/*
307 	 * The length of this blob is two times the size of a
308 	 * structure (av pair) which holds name/size
309 	 * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
310 	 * unicode length of a netbios domain name
311 	 */
312 	ses->auth_key.len = size + 2 * dlen;
313 	ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
314 	if (!ses->auth_key.response) {
315 		ses->auth_key.len = 0;
316 		cERROR(1, "Challenge target info allocation failure");
317 		return -ENOMEM;
318 	}
319 
320 	blobptr = ses->auth_key.response;
321 	attrptr = (struct ntlmssp2_name *) blobptr;
322 
323 	/*
324 	 * As defined in MS-NTLM 3.3.2, just this av pair field
325 	 * is sufficient as part of the temp
326 	 */
327 	attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
328 	attrptr->length = cpu_to_le16(2 * dlen);
329 	blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
330 	cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
331 
332 	return 0;
333 }
334 
335 /* Server has provided av pairs/target info in the type 2 challenge
336  * packet and we have plucked it and stored within smb session.
337  * We parse that blob here to find netbios domain name to be used
338  * as part of ntlmv2 authentication (in Target String), if not already
339  * specified on the command line.
340  * If this function returns without any error but without fetching
341  * domain name, authentication may fail against some server but
342  * may not fail against other (those who are not very particular
343  * about target string i.e. for some, just user name might suffice.
344  */
345 static int
find_domain_name(struct cifs_ses * ses,const struct nls_table * nls_cp)346 find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
347 {
348 	unsigned int attrsize;
349 	unsigned int type;
350 	unsigned int onesize = sizeof(struct ntlmssp2_name);
351 	unsigned char *blobptr;
352 	unsigned char *blobend;
353 	struct ntlmssp2_name *attrptr;
354 
355 	if (!ses->auth_key.len || !ses->auth_key.response)
356 		return 0;
357 
358 	blobptr = ses->auth_key.response;
359 	blobend = blobptr + ses->auth_key.len;
360 
361 	while (blobptr + onesize < blobend) {
362 		attrptr = (struct ntlmssp2_name *) blobptr;
363 		type = le16_to_cpu(attrptr->type);
364 		if (type == NTLMSSP_AV_EOL)
365 			break;
366 		blobptr += 2; /* advance attr type */
367 		attrsize = le16_to_cpu(attrptr->length);
368 		blobptr += 2; /* advance attr size */
369 		if (blobptr + attrsize > blobend)
370 			break;
371 		if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
372 			if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
373 				break;
374 			if (!ses->domainName) {
375 				ses->domainName =
376 					kmalloc(attrsize + 1, GFP_KERNEL);
377 				if (!ses->domainName)
378 						return -ENOMEM;
379 				cifs_from_utf16(ses->domainName,
380 					(__le16 *)blobptr, attrsize, attrsize,
381 					nls_cp, false);
382 				break;
383 			}
384 		}
385 		blobptr += attrsize; /* advance attr  value */
386 	}
387 
388 	return 0;
389 }
390 
calc_ntlmv2_hash(struct cifs_ses * ses,char * ntlmv2_hash,const struct nls_table * nls_cp)391 static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
392 			    const struct nls_table *nls_cp)
393 {
394 	int rc = 0;
395 	int len;
396 	char nt_hash[CIFS_NTHASH_SIZE];
397 	__le16 *user;
398 	wchar_t *domain;
399 	wchar_t *server;
400 
401 	if (!ses->server->secmech.sdeschmacmd5) {
402 		cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
403 		return -1;
404 	}
405 
406 	/* calculate md4 hash of password */
407 	E_md4hash(ses->password, nt_hash, nls_cp);
408 
409 	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
410 				CIFS_NTHASH_SIZE);
411 	if (rc) {
412 		cERROR(1, "%s: Could not set NT Hash as a key", __func__);
413 		return rc;
414 	}
415 
416 	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
417 	if (rc) {
418 		cERROR(1, "calc_ntlmv2_hash: could not init hmacmd5\n");
419 		return rc;
420 	}
421 
422 	/* convert ses->user_name to unicode */
423 	len = ses->user_name ? strlen(ses->user_name) : 0;
424 	user = kmalloc(2 + (len * 2), GFP_KERNEL);
425 	if (user == NULL) {
426 		cERROR(1, "calc_ntlmv2_hash: user mem alloc failure\n");
427 		rc = -ENOMEM;
428 		return rc;
429 	}
430 
431 	if (len) {
432 		len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
433 		UniStrupr(user);
434 	} else {
435 		memset(user, '\0', 2);
436 	}
437 
438 	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
439 				(char *)user, 2 * len);
440 	kfree(user);
441 	if (rc) {
442 		cERROR(1, "%s: Could not update with user\n", __func__);
443 		return rc;
444 	}
445 
446 	/* convert ses->domainName to unicode and uppercase */
447 	if (ses->domainName) {
448 		len = strlen(ses->domainName);
449 
450 		domain = kmalloc(2 + (len * 2), GFP_KERNEL);
451 		if (domain == NULL) {
452 			cERROR(1, "calc_ntlmv2_hash: domain mem alloc failure");
453 			rc = -ENOMEM;
454 			return rc;
455 		}
456 		len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
457 				      nls_cp);
458 		rc =
459 		crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
460 					(char *)domain, 2 * len);
461 		kfree(domain);
462 		if (rc) {
463 			cERROR(1, "%s: Could not update with domain\n",
464 								__func__);
465 			return rc;
466 		}
467 	} else if (ses->serverName) {
468 		len = strlen(ses->serverName);
469 
470 		server = kmalloc(2 + (len * 2), GFP_KERNEL);
471 		if (server == NULL) {
472 			cERROR(1, "calc_ntlmv2_hash: server mem alloc failure");
473 			rc = -ENOMEM;
474 			return rc;
475 		}
476 		len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
477 					nls_cp);
478 		rc =
479 		crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
480 					(char *)server, 2 * len);
481 		kfree(server);
482 		if (rc) {
483 			cERROR(1, "%s: Could not update with server\n",
484 								__func__);
485 			return rc;
486 		}
487 	}
488 
489 	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
490 					ntlmv2_hash);
491 	if (rc)
492 		cERROR(1, "%s: Could not generate md5 hash\n", __func__);
493 
494 	return rc;
495 }
496 
497 static int
CalcNTLMv2_response(const struct cifs_ses * ses,char * ntlmv2_hash)498 CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
499 {
500 	int rc;
501 	unsigned int offset = CIFS_SESS_KEY_SIZE + 8;
502 
503 	if (!ses->server->secmech.sdeschmacmd5) {
504 		cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
505 		return -1;
506 	}
507 
508 	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
509 				ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
510 	if (rc) {
511 		cERROR(1, "%s: Could not set NTLMV2 Hash as a key", __func__);
512 		return rc;
513 	}
514 
515 	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
516 	if (rc) {
517 		cERROR(1, "CalcNTLMv2_response: could not init hmacmd5");
518 		return rc;
519 	}
520 
521 	if (ses->server->secType == RawNTLMSSP)
522 		memcpy(ses->auth_key.response + offset,
523 			ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
524 	else
525 		memcpy(ses->auth_key.response + offset,
526 			ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
527 	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
528 		ses->auth_key.response + offset, ses->auth_key.len - offset);
529 	if (rc) {
530 		cERROR(1, "%s: Could not update with response\n", __func__);
531 		return rc;
532 	}
533 
534 	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
535 		ses->auth_key.response + CIFS_SESS_KEY_SIZE);
536 	if (rc)
537 		cERROR(1, "%s: Could not generate md5 hash\n", __func__);
538 
539 	return rc;
540 }
541 
542 
543 int
setup_ntlmv2_rsp(struct cifs_ses * ses,const struct nls_table * nls_cp)544 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
545 {
546 	int rc;
547 	int baselen;
548 	unsigned int tilen;
549 	struct ntlmv2_resp *buf;
550 	char ntlmv2_hash[16];
551 	unsigned char *tiblob = NULL; /* target info blob */
552 
553 	if (ses->server->secType == RawNTLMSSP) {
554 		if (!ses->domainName) {
555 			rc = find_domain_name(ses, nls_cp);
556 			if (rc) {
557 				cERROR(1, "error %d finding domain name", rc);
558 				goto setup_ntlmv2_rsp_ret;
559 			}
560 		}
561 	} else {
562 		rc = build_avpair_blob(ses, nls_cp);
563 		if (rc) {
564 			cERROR(1, "error %d building av pair blob", rc);
565 			goto setup_ntlmv2_rsp_ret;
566 		}
567 	}
568 
569 	baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
570 	tilen = ses->auth_key.len;
571 	tiblob = ses->auth_key.response;
572 
573 	ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
574 	if (!ses->auth_key.response) {
575 		rc = ENOMEM;
576 		ses->auth_key.len = 0;
577 		cERROR(1, "%s: Can't allocate auth blob", __func__);
578 		goto setup_ntlmv2_rsp_ret;
579 	}
580 	ses->auth_key.len += baselen;
581 
582 	buf = (struct ntlmv2_resp *)
583 			(ses->auth_key.response + CIFS_SESS_KEY_SIZE);
584 	buf->blob_signature = cpu_to_le32(0x00000101);
585 	buf->reserved = 0;
586 	buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
587 	get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
588 	buf->reserved2 = 0;
589 
590 	memcpy(ses->auth_key.response + baselen, tiblob, tilen);
591 
592 	/* calculate ntlmv2_hash */
593 	rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
594 	if (rc) {
595 		cERROR(1, "could not get v2 hash rc %d", rc);
596 		goto setup_ntlmv2_rsp_ret;
597 	}
598 
599 	/* calculate first part of the client response (CR1) */
600 	rc = CalcNTLMv2_response(ses, ntlmv2_hash);
601 	if (rc) {
602 		cERROR(1, "Could not calculate CR1  rc: %d", rc);
603 		goto setup_ntlmv2_rsp_ret;
604 	}
605 
606 	/* now calculate the session key for NTLMv2 */
607 	rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
608 		ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
609 	if (rc) {
610 		cERROR(1, "%s: Could not set NTLMV2 Hash as a key", __func__);
611 		goto setup_ntlmv2_rsp_ret;
612 	}
613 
614 	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
615 	if (rc) {
616 		cERROR(1, "%s: Could not init hmacmd5\n", __func__);
617 		goto setup_ntlmv2_rsp_ret;
618 	}
619 
620 	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
621 		ses->auth_key.response + CIFS_SESS_KEY_SIZE,
622 		CIFS_HMAC_MD5_HASH_SIZE);
623 	if (rc) {
624 		cERROR(1, "%s: Could not update with response\n", __func__);
625 		goto setup_ntlmv2_rsp_ret;
626 	}
627 
628 	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
629 		ses->auth_key.response);
630 	if (rc)
631 		cERROR(1, "%s: Could not generate md5 hash\n", __func__);
632 
633 setup_ntlmv2_rsp_ret:
634 	kfree(tiblob);
635 
636 	return rc;
637 }
638 
639 int
calc_seckey(struct cifs_ses * ses)640 calc_seckey(struct cifs_ses *ses)
641 {
642 	int rc;
643 	struct crypto_blkcipher *tfm_arc4;
644 	struct scatterlist sgin, sgout;
645 	struct blkcipher_desc desc;
646 	unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
647 
648 	get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
649 
650 	tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
651 	if (IS_ERR(tfm_arc4)) {
652 		rc = PTR_ERR(tfm_arc4);
653 		cERROR(1, "could not allocate crypto API arc4\n");
654 		return rc;
655 	}
656 
657 	desc.tfm = tfm_arc4;
658 
659 	rc = crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,
660 					CIFS_SESS_KEY_SIZE);
661 	if (rc) {
662 		cERROR(1, "%s: Could not set response as a key", __func__);
663 		return rc;
664 	}
665 
666 	sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
667 	sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
668 
669 	rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
670 	if (rc) {
671 		cERROR(1, "could not encrypt session key rc: %d\n", rc);
672 		crypto_free_blkcipher(tfm_arc4);
673 		return rc;
674 	}
675 
676 	/* make secondary_key/nonce as session key */
677 	memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
678 	/* and make len as that of session key only */
679 	ses->auth_key.len = CIFS_SESS_KEY_SIZE;
680 
681 	crypto_free_blkcipher(tfm_arc4);
682 
683 	return rc;
684 }
685 
686 void
cifs_crypto_shash_release(struct TCP_Server_Info * server)687 cifs_crypto_shash_release(struct TCP_Server_Info *server)
688 {
689 	if (server->secmech.md5)
690 		crypto_free_shash(server->secmech.md5);
691 
692 	if (server->secmech.hmacmd5)
693 		crypto_free_shash(server->secmech.hmacmd5);
694 
695 	kfree(server->secmech.sdeschmacmd5);
696 
697 	kfree(server->secmech.sdescmd5);
698 }
699 
700 int
cifs_crypto_shash_allocate(struct TCP_Server_Info * server)701 cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
702 {
703 	int rc;
704 	unsigned int size;
705 
706 	server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
707 	if (IS_ERR(server->secmech.hmacmd5)) {
708 		cERROR(1, "could not allocate crypto hmacmd5\n");
709 		return PTR_ERR(server->secmech.hmacmd5);
710 	}
711 
712 	server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
713 	if (IS_ERR(server->secmech.md5)) {
714 		cERROR(1, "could not allocate crypto md5\n");
715 		rc = PTR_ERR(server->secmech.md5);
716 		goto crypto_allocate_md5_fail;
717 	}
718 
719 	size = sizeof(struct shash_desc) +
720 			crypto_shash_descsize(server->secmech.hmacmd5);
721 	server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
722 	if (!server->secmech.sdeschmacmd5) {
723 		cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5\n");
724 		rc = -ENOMEM;
725 		goto crypto_allocate_hmacmd5_sdesc_fail;
726 	}
727 	server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
728 	server->secmech.sdeschmacmd5->shash.flags = 0x0;
729 
730 
731 	size = sizeof(struct shash_desc) +
732 			crypto_shash_descsize(server->secmech.md5);
733 	server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
734 	if (!server->secmech.sdescmd5) {
735 		cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5\n");
736 		rc = -ENOMEM;
737 		goto crypto_allocate_md5_sdesc_fail;
738 	}
739 	server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
740 	server->secmech.sdescmd5->shash.flags = 0x0;
741 
742 	return 0;
743 
744 crypto_allocate_md5_sdesc_fail:
745 	kfree(server->secmech.sdeschmacmd5);
746 
747 crypto_allocate_hmacmd5_sdesc_fail:
748 	crypto_free_shash(server->secmech.md5);
749 
750 crypto_allocate_md5_fail:
751 	crypto_free_shash(server->secmech.hmacmd5);
752 
753 	return rc;
754 }
755