2 * fs/cifs/cifsencrypt.c
4 * Copyright (C) International Business Machines Corp., 2005,2006
5 * Author(s): Steve French (sfrench@us.ibm.com)
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.
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.
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
23 #include <linux/slab.h>
26 #include "cifs_debug.h"
27 #include "cifs_unicode.h"
28 #include "cifsproto.h"
30 #include <linux/ctype.h>
31 #include <linux/random.h>
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.
40 static int cifs_calc_signature(const struct kvec *iov, int n_vec,
41 struct TCP_Server_Info *server, char *signature)
46 if (iov == NULL || signature == NULL || server == NULL)
49 if (!server->secmech.sdescmd5) {
50 cERROR(1, "%s: Can't generate signature\n", __func__);
54 rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
56 cERROR(1, "%s: Could not init md5\n", __func__);
60 rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
61 server->session_key.response, server->session_key.len);
63 cERROR(1, "%s: Could not update with response\n", __func__);
67 for (i = 0; i < n_vec; i++) {
68 if (iov[i].iov_len == 0)
70 if (iov[i].iov_base == NULL) {
71 cERROR(1, "null iovec entry");
74 /* The first entry includes a length field (which does not get
75 signed that occupies the first 4 bytes before the header */
77 if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
78 break; /* nothing to sign or corrupt header */
80 crypto_shash_update(&server->secmech.sdescmd5->shash,
81 iov[i].iov_base + 4, iov[i].iov_len - 4);
84 crypto_shash_update(&server->secmech.sdescmd5->shash,
85 iov[i].iov_base, iov[i].iov_len);
88 cERROR(1, "%s: Could not update with payload\n",
94 rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
96 cERROR(1, "%s: Could not generate md5 hash\n", __func__);
101 /* must be called with server->srv_mutex held */
102 int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
103 __u32 *pexpected_response_sequence_number)
106 char smb_signature[20];
107 struct smb_hdr *cifs_pdu = (struct smb_hdr *)iov[0].iov_base;
109 if ((cifs_pdu == NULL) || (server == NULL))
112 if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
113 server->tcpStatus == CifsNeedNegotiate)
116 if (!server->session_estab) {
117 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
121 cifs_pdu->Signature.Sequence.SequenceNumber =
122 cpu_to_le32(server->sequence_number);
123 cifs_pdu->Signature.Sequence.Reserved = 0;
125 *pexpected_response_sequence_number = server->sequence_number++;
126 server->sequence_number++;
128 rc = cifs_calc_signature(iov, n_vec, server, smb_signature);
130 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
132 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
137 /* must be called with server->srv_mutex held */
138 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
139 __u32 *pexpected_response_sequence_number)
143 iov.iov_base = cifs_pdu;
144 iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
146 return cifs_sign_smb2(&iov, 1, server,
147 pexpected_response_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)
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;
159 if (cifs_pdu == NULL || server == NULL)
162 if (!server->session_estab)
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)
172 /* BB what if signatures are supposed to be on for session but
173 server does not send one? BB */
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",
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);
184 cifs_pdu->Signature.Sequence.SequenceNumber =
185 cpu_to_le32(expected_sequence_number);
186 cifs_pdu->Signature.Sequence.Reserved = 0;
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);
196 /* cifs_dump_mem("what we think it should be: ",
197 what_we_think_sig_should_be, 16); */
199 if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
206 /* first calculate 24 bytes ntlm response and then 16 byte session key */
207 int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
210 unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
211 char temp_key[CIFS_SESS_KEY_SIZE];
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);
221 ses->auth_key.len = temp_len;
223 rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
224 ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
226 cFYI(1, "%s Can't generate NTLM response, error: %d",
231 rc = E_md4hash(ses->password, temp_key, nls_cp);
233 cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
237 rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
239 cFYI(1, "%s Can't generate NTLM session key, error: %d",
245 #ifdef CONFIG_CIFS_WEAK_PW_HASH
246 int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
247 char *lnm_session_key)
251 char password_with_pad[CIFS_ENCPWD_SIZE];
253 memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
255 strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
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,
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. */
275 for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
276 password_with_pad[i] = toupper(password_with_pad[i]);
278 rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
282 #endif /* CIFS_WEAK_PW_HASH */
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.
290 build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
293 unsigned int size = 2 * sizeof(struct ntlmssp2_name);
294 char *defdmname = "WORKGROUP";
295 unsigned char *blobptr;
296 struct ntlmssp2_name *attrptr;
298 if (!ses->domainName) {
299 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
300 if (!ses->domainName)
304 dlen = strlen(ses->domainName);
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
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");
320 blobptr = ses->auth_key.response;
321 attrptr = (struct ntlmssp2_name *) blobptr;
324 * As defined in MS-NTLM 3.3.2, just this av pair field
325 * is sufficient as part of the temp
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_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
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.
346 find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
348 unsigned int attrsize;
350 unsigned int onesize = sizeof(struct ntlmssp2_name);
351 unsigned char *blobptr;
352 unsigned char *blobend;
353 struct ntlmssp2_name *attrptr;
355 if (!ses->auth_key.len || !ses->auth_key.response)
358 blobptr = ses->auth_key.response;
359 blobend = blobptr + ses->auth_key.len;
361 while (blobptr + onesize < blobend) {
362 attrptr = (struct ntlmssp2_name *) blobptr;
363 type = le16_to_cpu(attrptr->type);
364 if (type == NTLMSSP_AV_EOL)
366 blobptr += 2; /* advance attr type */
367 attrsize = le16_to_cpu(attrptr->length);
368 blobptr += 2; /* advance attr size */
369 if (blobptr + attrsize > blobend)
371 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
374 if (!ses->domainName) {
376 kmalloc(attrsize + 1, GFP_KERNEL);
377 if (!ses->domainName)
379 cifs_from_ucs2(ses->domainName,
380 (__le16 *)blobptr, attrsize, attrsize,
385 blobptr += attrsize; /* advance attr value */
391 static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
392 const struct nls_table *nls_cp)
396 char nt_hash[CIFS_NTHASH_SIZE];
401 if (!ses->server->secmech.sdeschmacmd5) {
402 cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
406 /* calculate md4 hash of password */
407 E_md4hash(ses->password, nt_hash, nls_cp);
409 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
412 cERROR(1, "%s: Could not set NT Hash as a key", __func__);
416 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
418 cERROR(1, "calc_ntlmv2_hash: could not init hmacmd5\n");
422 /* convert ses->user_name to unicode and uppercase */
423 len = strlen(ses->user_name);
424 user = kmalloc(2 + (len * 2), GFP_KERNEL);
426 cERROR(1, "calc_ntlmv2_hash: user mem alloc failure\n");
430 len = cifs_strtoUCS((__le16 *)user, ses->user_name, len, nls_cp);
433 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
434 (char *)user, 2 * len);
437 cERROR(1, "%s: Could not update with user\n", __func__);
441 /* convert ses->domainName to unicode and uppercase */
442 if (ses->domainName) {
443 len = strlen(ses->domainName);
445 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
446 if (domain == NULL) {
447 cERROR(1, "calc_ntlmv2_hash: domain mem alloc failure");
451 len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len,
454 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
455 (char *)domain, 2 * len);
458 cERROR(1, "%s: Could not update with domain\n",
462 } else if (ses->serverName) {
463 len = strlen(ses->serverName);
465 server = kmalloc(2 + (len * 2), GFP_KERNEL);
466 if (server == NULL) {
467 cERROR(1, "calc_ntlmv2_hash: server mem alloc failure");
471 len = cifs_strtoUCS((__le16 *)server, ses->serverName, len,
474 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
475 (char *)server, 2 * len);
478 cERROR(1, "%s: Could not update with server\n",
484 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
487 cERROR(1, "%s: Could not generate md5 hash\n", __func__);
493 CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
496 unsigned int offset = CIFS_SESS_KEY_SIZE + 8;
498 if (!ses->server->secmech.sdeschmacmd5) {
499 cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
503 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
504 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
506 cERROR(1, "%s: Could not set NTLMV2 Hash as a key", __func__);
510 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
512 cERROR(1, "CalcNTLMv2_response: could not init hmacmd5");
516 if (ses->server->secType == RawNTLMSSP)
517 memcpy(ses->auth_key.response + offset,
518 ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
520 memcpy(ses->auth_key.response + offset,
521 ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
522 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
523 ses->auth_key.response + offset, ses->auth_key.len - offset);
525 cERROR(1, "%s: Could not update with response\n", __func__);
529 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
530 ses->auth_key.response + CIFS_SESS_KEY_SIZE);
532 cERROR(1, "%s: Could not generate md5 hash\n", __func__);
539 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
544 struct ntlmv2_resp *buf;
545 char ntlmv2_hash[16];
546 unsigned char *tiblob = NULL; /* target info blob */
548 if (ses->server->secType == RawNTLMSSP) {
549 if (!ses->domainName) {
550 rc = find_domain_name(ses, nls_cp);
552 cERROR(1, "error %d finding domain name", rc);
553 goto setup_ntlmv2_rsp_ret;
557 rc = build_avpair_blob(ses, nls_cp);
559 cERROR(1, "error %d building av pair blob", rc);
560 goto setup_ntlmv2_rsp_ret;
564 baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
565 tilen = ses->auth_key.len;
566 tiblob = ses->auth_key.response;
568 ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
569 if (!ses->auth_key.response) {
571 ses->auth_key.len = 0;
572 cERROR(1, "%s: Can't allocate auth blob", __func__);
573 goto setup_ntlmv2_rsp_ret;
575 ses->auth_key.len += baselen;
577 buf = (struct ntlmv2_resp *)
578 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
579 buf->blob_signature = cpu_to_le32(0x00000101);
581 buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
582 get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
585 memcpy(ses->auth_key.response + baselen, tiblob, tilen);
587 /* calculate ntlmv2_hash */
588 rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
590 cERROR(1, "could not get v2 hash rc %d", rc);
591 goto setup_ntlmv2_rsp_ret;
594 /* calculate first part of the client response (CR1) */
595 rc = CalcNTLMv2_response(ses, ntlmv2_hash);
597 cERROR(1, "Could not calculate CR1 rc: %d", rc);
598 goto setup_ntlmv2_rsp_ret;
601 /* now calculate the session key for NTLMv2 */
602 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
603 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
605 cERROR(1, "%s: Could not set NTLMV2 Hash as a key", __func__);
606 goto setup_ntlmv2_rsp_ret;
609 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
611 cERROR(1, "%s: Could not init hmacmd5\n", __func__);
612 goto setup_ntlmv2_rsp_ret;
615 rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
616 ses->auth_key.response + CIFS_SESS_KEY_SIZE,
617 CIFS_HMAC_MD5_HASH_SIZE);
619 cERROR(1, "%s: Could not update with response\n", __func__);
620 goto setup_ntlmv2_rsp_ret;
623 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
624 ses->auth_key.response);
626 cERROR(1, "%s: Could not generate md5 hash\n", __func__);
628 setup_ntlmv2_rsp_ret:
635 calc_seckey(struct cifs_ses *ses)
638 struct crypto_blkcipher *tfm_arc4;
639 struct scatterlist sgin, sgout;
640 struct blkcipher_desc desc;
641 unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
643 get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
645 tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
646 if (IS_ERR(tfm_arc4)) {
647 rc = PTR_ERR(tfm_arc4);
648 cERROR(1, "could not allocate crypto API arc4\n");
654 rc = crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,
657 cERROR(1, "%s: Could not set response as a key", __func__);
661 sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
662 sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
664 rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
666 cERROR(1, "could not encrypt session key rc: %d\n", rc);
667 crypto_free_blkcipher(tfm_arc4);
671 /* make secondary_key/nonce as session key */
672 memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
673 /* and make len as that of session key only */
674 ses->auth_key.len = CIFS_SESS_KEY_SIZE;
676 crypto_free_blkcipher(tfm_arc4);
682 cifs_crypto_shash_release(struct TCP_Server_Info *server)
684 if (server->secmech.md5)
685 crypto_free_shash(server->secmech.md5);
687 if (server->secmech.hmacmd5)
688 crypto_free_shash(server->secmech.hmacmd5);
690 kfree(server->secmech.sdeschmacmd5);
692 kfree(server->secmech.sdescmd5);
696 cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
701 server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
702 if (IS_ERR(server->secmech.hmacmd5)) {
703 cERROR(1, "could not allocate crypto hmacmd5\n");
704 return PTR_ERR(server->secmech.hmacmd5);
707 server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
708 if (IS_ERR(server->secmech.md5)) {
709 cERROR(1, "could not allocate crypto md5\n");
710 rc = PTR_ERR(server->secmech.md5);
711 goto crypto_allocate_md5_fail;
714 size = sizeof(struct shash_desc) +
715 crypto_shash_descsize(server->secmech.hmacmd5);
716 server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
717 if (!server->secmech.sdeschmacmd5) {
718 cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5\n");
720 goto crypto_allocate_hmacmd5_sdesc_fail;
722 server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
723 server->secmech.sdeschmacmd5->shash.flags = 0x0;
726 size = sizeof(struct shash_desc) +
727 crypto_shash_descsize(server->secmech.md5);
728 server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
729 if (!server->secmech.sdescmd5) {
730 cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5\n");
732 goto crypto_allocate_md5_sdesc_fail;
734 server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
735 server->secmech.sdescmd5->shash.flags = 0x0;
739 crypto_allocate_md5_sdesc_fail:
740 kfree(server->secmech.sdeschmacmd5);
742 crypto_allocate_hmacmd5_sdesc_fail:
743 crypto_free_shash(server->secmech.md5);
745 crypto_allocate_md5_fail:
746 crypto_free_shash(server->secmech.hmacmd5);