1 // SPDX-License-Identifier: LGPL-2.1
4 * Encryption and hashing operations relating to NTLM, NTLMv2. See MS-NLMP
5 * for more detailed information
7 * Copyright (C) International Business Machines Corp., 2005,2013
8 * Author(s): Steve French (sfrench@us.ibm.com)
13 #include <linux/slab.h>
16 #include "cifs_debug.h"
17 #include "cifs_unicode.h"
18 #include "cifsproto.h"
20 #include <linux/ctype.h>
21 #include <linux/random.h>
22 #include <linux/highmem.h>
23 #include <linux/fips.h>
24 #include "../smbfs_common/arc4.h"
25 #include <crypto/aead.h>
27 int __cifs_calc_signature(struct smb_rqst *rqst,
28 struct TCP_Server_Info *server, char *signature,
29 struct shash_desc *shash)
33 struct kvec *iov = rqst->rq_iov;
34 int n_vec = rqst->rq_nvec;
36 /* iov[0] is actual data and not the rfc1002 length for SMB2+ */
37 if (!is_smb1(server)) {
38 if (iov[0].iov_len <= 4)
42 if (n_vec < 2 || iov[0].iov_len != 4)
44 i = 1; /* skip rfc1002 length */
47 for (; i < n_vec; i++) {
48 if (iov[i].iov_len == 0)
50 if (iov[i].iov_base == NULL) {
51 cifs_dbg(VFS, "null iovec entry\n");
55 rc = crypto_shash_update(shash,
56 iov[i].iov_base, iov[i].iov_len);
58 cifs_dbg(VFS, "%s: Could not update with payload\n",
64 /* now hash over the rq_pages array */
65 for (i = 0; i < rqst->rq_npages; i++) {
67 unsigned int len, offset;
69 rqst_page_get_length(rqst, i, &len, &offset);
71 kaddr = (char *) kmap(rqst->rq_pages[i]) + offset;
73 rc = crypto_shash_update(shash, kaddr, len);
75 cifs_dbg(VFS, "%s: Could not update with payload\n",
77 kunmap(rqst->rq_pages[i]);
81 kunmap(rqst->rq_pages[i]);
84 rc = crypto_shash_final(shash, signature);
86 cifs_dbg(VFS, "%s: Could not generate hash\n", __func__);
92 * Calculate and return the CIFS signature based on the mac key and SMB PDU.
93 * The 16 byte signature must be allocated by the caller. Note we only use the
94 * 1st eight bytes and that the smb header signature field on input contains
95 * the sequence number before this function is called. Also, this function
96 * should be called with the server->srv_mutex held.
98 static int cifs_calc_signature(struct smb_rqst *rqst,
99 struct TCP_Server_Info *server, char *signature)
103 if (!rqst->rq_iov || !signature || !server)
106 rc = cifs_alloc_hash("md5", &server->secmech.md5);
110 rc = crypto_shash_init(server->secmech.md5);
112 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
116 rc = crypto_shash_update(server->secmech.md5,
117 server->session_key.response, server->session_key.len);
119 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
123 return __cifs_calc_signature(rqst, server, signature, server->secmech.md5);
126 /* must be called with server->srv_mutex held */
127 int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
128 __u32 *pexpected_response_sequence_number)
131 char smb_signature[20];
132 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
134 if (rqst->rq_iov[0].iov_len != 4 ||
135 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
138 if ((cifs_pdu == NULL) || (server == NULL))
141 spin_lock(&server->srv_lock);
142 if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
143 server->tcpStatus == CifsNeedNegotiate) {
144 spin_unlock(&server->srv_lock);
147 spin_unlock(&server->srv_lock);
149 if (!server->session_estab) {
150 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
154 cifs_pdu->Signature.Sequence.SequenceNumber =
155 cpu_to_le32(server->sequence_number);
156 cifs_pdu->Signature.Sequence.Reserved = 0;
158 *pexpected_response_sequence_number = ++server->sequence_number;
159 ++server->sequence_number;
161 rc = cifs_calc_signature(rqst, server, smb_signature);
163 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
165 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
170 int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
171 __u32 *pexpected_response_sequence)
173 struct smb_rqst rqst = { .rq_iov = iov,
176 return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
179 /* must be called with server->srv_mutex held */
180 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
181 __u32 *pexpected_response_sequence_number)
185 iov[0].iov_base = cifs_pdu;
187 iov[1].iov_base = (char *)cifs_pdu + 4;
188 iov[1].iov_len = be32_to_cpu(cifs_pdu->smb_buf_length);
190 return cifs_sign_smbv(iov, 2, server,
191 pexpected_response_sequence_number);
194 int cifs_verify_signature(struct smb_rqst *rqst,
195 struct TCP_Server_Info *server,
196 __u32 expected_sequence_number)
199 char server_response_sig[8];
200 char what_we_think_sig_should_be[20];
201 struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
203 if (rqst->rq_iov[0].iov_len != 4 ||
204 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
207 if (cifs_pdu == NULL || server == NULL)
210 if (!server->session_estab)
213 if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
214 struct smb_com_lock_req *pSMB =
215 (struct smb_com_lock_req *)cifs_pdu;
216 if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
220 /* BB what if signatures are supposed to be on for session but
221 server does not send one? BB */
223 /* Do not need to verify session setups with signature "BSRSPYL " */
224 if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
225 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
228 /* save off the origiginal signature so we can modify the smb and check
229 its signature against what the server sent */
230 memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
232 cifs_pdu->Signature.Sequence.SequenceNumber =
233 cpu_to_le32(expected_sequence_number);
234 cifs_pdu->Signature.Sequence.Reserved = 0;
236 cifs_server_lock(server);
237 rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
238 cifs_server_unlock(server);
243 /* cifs_dump_mem("what we think it should be: ",
244 what_we_think_sig_should_be, 16); */
246 if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
253 /* Build a proper attribute value/target info pairs blob.
254 * Fill in netbios and dns domain name and workstation name
255 * and client time (total five av pairs and + one end of fields indicator.
256 * Allocate domain name which gets freed when session struct is deallocated.
259 build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
262 unsigned int size = 2 * sizeof(struct ntlmssp2_name);
263 char *defdmname = "WORKGROUP";
264 unsigned char *blobptr;
265 struct ntlmssp2_name *attrptr;
267 if (!ses->domainName) {
268 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
269 if (!ses->domainName)
273 dlen = strlen(ses->domainName);
276 * The length of this blob is two times the size of a
277 * structure (av pair) which holds name/size
278 * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
279 * unicode length of a netbios domain name
281 ses->auth_key.len = size + 2 * dlen;
282 ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
283 if (!ses->auth_key.response) {
284 ses->auth_key.len = 0;
288 blobptr = ses->auth_key.response;
289 attrptr = (struct ntlmssp2_name *) blobptr;
292 * As defined in MS-NTLM 3.3.2, just this av pair field
293 * is sufficient as part of the temp
295 attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
296 attrptr->length = cpu_to_le16(2 * dlen);
297 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
298 cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
303 /* Server has provided av pairs/target info in the type 2 challenge
304 * packet and we have plucked it and stored within smb session.
305 * We parse that blob here to find netbios domain name to be used
306 * as part of ntlmv2 authentication (in Target String), if not already
307 * specified on the command line.
308 * If this function returns without any error but without fetching
309 * domain name, authentication may fail against some server but
310 * may not fail against other (those who are not very particular
311 * about target string i.e. for some, just user name might suffice.
314 find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
316 unsigned int attrsize;
318 unsigned int onesize = sizeof(struct ntlmssp2_name);
319 unsigned char *blobptr;
320 unsigned char *blobend;
321 struct ntlmssp2_name *attrptr;
323 if (!ses->auth_key.len || !ses->auth_key.response)
326 blobptr = ses->auth_key.response;
327 blobend = blobptr + ses->auth_key.len;
329 while (blobptr + onesize < blobend) {
330 attrptr = (struct ntlmssp2_name *) blobptr;
331 type = le16_to_cpu(attrptr->type);
332 if (type == NTLMSSP_AV_EOL)
334 blobptr += 2; /* advance attr type */
335 attrsize = le16_to_cpu(attrptr->length);
336 blobptr += 2; /* advance attr size */
337 if (blobptr + attrsize > blobend)
339 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
340 if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
342 if (!ses->domainName) {
344 kmalloc(attrsize + 1, GFP_KERNEL);
345 if (!ses->domainName)
347 cifs_from_utf16(ses->domainName,
348 (__le16 *)blobptr, attrsize, attrsize,
349 nls_cp, NO_MAP_UNI_RSVD);
353 blobptr += attrsize; /* advance attr value */
359 /* Server has provided av pairs/target info in the type 2 challenge
360 * packet and we have plucked it and stored within smb session.
361 * We parse that blob here to find the server given timestamp
362 * as part of ntlmv2 authentication (or local current time as
363 * default in case of failure)
366 find_timestamp(struct cifs_ses *ses)
368 unsigned int attrsize;
370 unsigned int onesize = sizeof(struct ntlmssp2_name);
371 unsigned char *blobptr;
372 unsigned char *blobend;
373 struct ntlmssp2_name *attrptr;
374 struct timespec64 ts;
376 if (!ses->auth_key.len || !ses->auth_key.response)
379 blobptr = ses->auth_key.response;
380 blobend = blobptr + ses->auth_key.len;
382 while (blobptr + onesize < blobend) {
383 attrptr = (struct ntlmssp2_name *) blobptr;
384 type = le16_to_cpu(attrptr->type);
385 if (type == NTLMSSP_AV_EOL)
387 blobptr += 2; /* advance attr type */
388 attrsize = le16_to_cpu(attrptr->length);
389 blobptr += 2; /* advance attr size */
390 if (blobptr + attrsize > blobend)
392 if (type == NTLMSSP_AV_TIMESTAMP) {
393 if (attrsize == sizeof(u64))
394 return *((__le64 *)blobptr);
396 blobptr += attrsize; /* advance attr value */
399 ktime_get_real_ts64(&ts);
400 return cpu_to_le64(cifs_UnixTimeToNT(ts));
403 static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
404 const struct nls_table *nls_cp)
408 char nt_hash[CIFS_NTHASH_SIZE];
413 if (!ses->server->secmech.hmacmd5) {
414 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
418 /* calculate md4 hash of password */
419 E_md4hash(ses->password, nt_hash, nls_cp);
421 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm, nt_hash,
424 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
428 rc = crypto_shash_init(ses->server->secmech.hmacmd5);
430 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
434 /* convert ses->user_name to unicode */
435 len = ses->user_name ? strlen(ses->user_name) : 0;
436 user = kmalloc(2 + (len * 2), GFP_KERNEL);
443 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
446 memset(user, '\0', 2);
449 rc = crypto_shash_update(ses->server->secmech.hmacmd5,
450 (char *)user, 2 * len);
453 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
457 /* convert ses->domainName to unicode and uppercase */
458 if (ses->domainName) {
459 len = strlen(ses->domainName);
461 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
462 if (domain == NULL) {
466 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
469 crypto_shash_update(ses->server->secmech.hmacmd5,
470 (char *)domain, 2 * len);
473 cifs_dbg(VFS, "%s: Could not update with domain\n",
478 /* We use ses->ip_addr if no domain name available */
479 len = strlen(ses->ip_addr);
481 server = kmalloc(2 + (len * 2), GFP_KERNEL);
482 if (server == NULL) {
486 len = cifs_strtoUTF16((__le16 *)server, ses->ip_addr, len,
489 crypto_shash_update(ses->server->secmech.hmacmd5,
490 (char *)server, 2 * len);
493 cifs_dbg(VFS, "%s: Could not update with server\n",
499 rc = crypto_shash_final(ses->server->secmech.hmacmd5,
502 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
508 CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
511 struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
512 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
513 unsigned int hash_len;
515 /* The MD5 hash starts at challenge_key.key */
516 hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
517 offsetof(struct ntlmv2_resp, challenge.key[0]));
519 if (!ses->server->secmech.hmacmd5) {
520 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
524 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm,
525 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
527 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
532 rc = crypto_shash_init(ses->server->secmech.hmacmd5);
534 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
538 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
539 memcpy(ntlmv2->challenge.key,
540 ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
542 memcpy(ntlmv2->challenge.key,
543 ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
544 rc = crypto_shash_update(ses->server->secmech.hmacmd5,
545 ntlmv2->challenge.key, hash_len);
547 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
551 /* Note that the MD5 digest over writes anon.challenge_key.key */
552 rc = crypto_shash_final(ses->server->secmech.hmacmd5,
553 ntlmv2->ntlmv2_hash);
555 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
561 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
566 struct ntlmv2_resp *ntlmv2;
567 char ntlmv2_hash[16];
568 unsigned char *tiblob = NULL; /* target info blob */
569 __le64 rsp_timestamp;
571 if (nls_cp == NULL) {
572 cifs_dbg(VFS, "%s called with nls_cp==NULL\n", __func__);
576 if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
577 if (!ses->domainName) {
578 if (ses->domainAuto) {
579 rc = find_domain_name(ses, nls_cp);
581 cifs_dbg(VFS, "error %d finding domain name\n",
583 goto setup_ntlmv2_rsp_ret;
586 ses->domainName = kstrdup("", GFP_KERNEL);
590 rc = build_avpair_blob(ses, nls_cp);
592 cifs_dbg(VFS, "error %d building av pair blob\n", rc);
593 goto setup_ntlmv2_rsp_ret;
597 /* Must be within 5 minutes of the server (or in range +/-2h
598 * in case of Mac OS X), so simply carry over server timestamp
599 * (as Windows 7 does)
601 rsp_timestamp = find_timestamp(ses);
603 baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
604 tilen = ses->auth_key.len;
605 tiblob = ses->auth_key.response;
607 ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
608 if (!ses->auth_key.response) {
610 ses->auth_key.len = 0;
611 goto setup_ntlmv2_rsp_ret;
613 ses->auth_key.len += baselen;
615 ntlmv2 = (struct ntlmv2_resp *)
616 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
617 ntlmv2->blob_signature = cpu_to_le32(0x00000101);
618 ntlmv2->reserved = 0;
619 ntlmv2->time = rsp_timestamp;
621 get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
622 ntlmv2->reserved2 = 0;
624 memcpy(ses->auth_key.response + baselen, tiblob, tilen);
626 cifs_server_lock(ses->server);
628 rc = cifs_alloc_hash("hmac(md5)", &ses->server->secmech.hmacmd5);
633 /* calculate ntlmv2_hash */
634 rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
636 cifs_dbg(VFS, "Could not get v2 hash rc %d\n", rc);
640 /* calculate first part of the client response (CR1) */
641 rc = CalcNTLMv2_response(ses, ntlmv2_hash);
643 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
647 /* now calculate the session key for NTLMv2 */
648 rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm,
649 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
651 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
656 rc = crypto_shash_init(ses->server->secmech.hmacmd5);
658 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
662 rc = crypto_shash_update(ses->server->secmech.hmacmd5,
664 CIFS_HMAC_MD5_HASH_SIZE);
666 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
670 rc = crypto_shash_final(ses->server->secmech.hmacmd5,
671 ses->auth_key.response);
673 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
676 cifs_server_unlock(ses->server);
677 setup_ntlmv2_rsp_ret:
678 kfree_sensitive(tiblob);
684 calc_seckey(struct cifs_ses *ses)
686 unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
687 struct arc4_ctx *ctx_arc4;
692 get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
694 ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL);
696 cifs_dbg(VFS, "Could not allocate arc4 context\n");
700 cifs_arc4_setkey(ctx_arc4, ses->auth_key.response, CIFS_SESS_KEY_SIZE);
701 cifs_arc4_crypt(ctx_arc4, ses->ntlmssp->ciphertext, sec_key,
704 /* make secondary_key/nonce as session key */
705 memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
706 /* and make len as that of session key only */
707 ses->auth_key.len = CIFS_SESS_KEY_SIZE;
709 memzero_explicit(sec_key, CIFS_SESS_KEY_SIZE);
710 kfree_sensitive(ctx_arc4);
715 cifs_crypto_secmech_release(struct TCP_Server_Info *server)
717 cifs_free_hash(&server->secmech.aes_cmac);
718 cifs_free_hash(&server->secmech.hmacsha256);
719 cifs_free_hash(&server->secmech.md5);
720 cifs_free_hash(&server->secmech.sha512);
721 cifs_free_hash(&server->secmech.hmacmd5);
723 if (server->secmech.enc) {
724 crypto_free_aead(server->secmech.enc);
725 server->secmech.enc = NULL;
728 if (server->secmech.dec) {
729 crypto_free_aead(server->secmech.dec);
730 server->secmech.dec = NULL;