~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/smb/client/cifsencrypt.c

Version: ~ [ linux-6.11-rc3 ] ~ [ linux-6.10.4 ] ~ [ linux-6.9.12 ] ~ [ linux-6.8.12 ] ~ [ linux-6.7.12 ] ~ [ linux-6.6.45 ] ~ [ linux-6.5.13 ] ~ [ linux-6.4.16 ] ~ [ linux-6.3.13 ] ~ [ linux-6.2.16 ] ~ [ linux-6.1.104 ] ~ [ linux-6.0.19 ] ~ [ linux-5.19.17 ] ~ [ linux-5.18.19 ] ~ [ linux-5.17.15 ] ~ [ linux-5.16.20 ] ~ [ linux-5.15.164 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.223 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.281 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.319 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.336 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.337 ] ~ [ linux-4.4.302 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.9 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 // SPDX-License-Identifier: LGPL-2.1
  2 /*
  3  *
  4  *   Encryption and hashing operations relating to NTLM, NTLMv2.  See MS-NLMP
  5  *   for more detailed information
  6  *
  7  *   Copyright (C) International Business Machines  Corp., 2005,2013
  8  *   Author(s): Steve French (sfrench@us.ibm.com)
  9  *
 10  */
 11 
 12 #include <linux/fs.h>
 13 #include <linux/slab.h>
 14 #include "cifspdu.h"
 15 #include "cifsglob.h"
 16 #include "cifs_debug.h"
 17 #include "cifs_unicode.h"
 18 #include "cifsproto.h"
 19 #include "ntlmssp.h"
 20 #include <linux/ctype.h>
 21 #include <linux/random.h>
 22 #include <linux/highmem.h>
 23 #include <linux/fips.h>
 24 #include "../common/arc4.h"
 25 #include <crypto/aead.h>
 26 
 27 /*
 28  * Hash data from a BVEC-type iterator.
 29  */
 30 static int cifs_shash_bvec(const struct iov_iter *iter, ssize_t maxsize,
 31                            struct shash_desc *shash)
 32 {
 33         const struct bio_vec *bv = iter->bvec;
 34         unsigned long start = iter->iov_offset;
 35         unsigned int i;
 36         void *p;
 37         int ret;
 38 
 39         for (i = 0; i < iter->nr_segs; i++) {
 40                 size_t off, len;
 41 
 42                 len = bv[i].bv_len;
 43                 if (start >= len) {
 44                         start -= len;
 45                         continue;
 46                 }
 47 
 48                 len = min_t(size_t, maxsize, len - start);
 49                 off = bv[i].bv_offset + start;
 50 
 51                 p = kmap_local_page(bv[i].bv_page);
 52                 ret = crypto_shash_update(shash, p + off, len);
 53                 kunmap_local(p);
 54                 if (ret < 0)
 55                         return ret;
 56 
 57                 maxsize -= len;
 58                 if (maxsize <= 0)
 59                         break;
 60                 start = 0;
 61         }
 62 
 63         return 0;
 64 }
 65 
 66 /*
 67  * Hash data from a KVEC-type iterator.
 68  */
 69 static int cifs_shash_kvec(const struct iov_iter *iter, ssize_t maxsize,
 70                            struct shash_desc *shash)
 71 {
 72         const struct kvec *kv = iter->kvec;
 73         unsigned long start = iter->iov_offset;
 74         unsigned int i;
 75         int ret;
 76 
 77         for (i = 0; i < iter->nr_segs; i++) {
 78                 size_t len;
 79 
 80                 len = kv[i].iov_len;
 81                 if (start >= len) {
 82                         start -= len;
 83                         continue;
 84                 }
 85 
 86                 len = min_t(size_t, maxsize, len - start);
 87                 ret = crypto_shash_update(shash, kv[i].iov_base + start, len);
 88                 if (ret < 0)
 89                         return ret;
 90                 maxsize -= len;
 91 
 92                 if (maxsize <= 0)
 93                         break;
 94                 start = 0;
 95         }
 96 
 97         return 0;
 98 }
 99 
100 /*
101  * Hash data from an XARRAY-type iterator.
102  */
103 static ssize_t cifs_shash_xarray(const struct iov_iter *iter, ssize_t maxsize,
104                                  struct shash_desc *shash)
105 {
106         struct folio *folios[16], *folio;
107         unsigned int nr, i, j, npages;
108         loff_t start = iter->xarray_start + iter->iov_offset;
109         pgoff_t last, index = start / PAGE_SIZE;
110         ssize_t ret = 0;
111         size_t len, offset, foffset;
112         void *p;
113 
114         if (maxsize == 0)
115                 return 0;
116 
117         last = (start + maxsize - 1) / PAGE_SIZE;
118         do {
119                 nr = xa_extract(iter->xarray, (void **)folios, index, last,
120                                 ARRAY_SIZE(folios), XA_PRESENT);
121                 if (nr == 0)
122                         return -EIO;
123 
124                 for (i = 0; i < nr; i++) {
125                         folio = folios[i];
126                         npages = folio_nr_pages(folio);
127                         foffset = start - folio_pos(folio);
128                         offset = foffset % PAGE_SIZE;
129                         for (j = foffset / PAGE_SIZE; j < npages; j++) {
130                                 len = min_t(size_t, maxsize, PAGE_SIZE - offset);
131                                 p = kmap_local_page(folio_page(folio, j));
132                                 ret = crypto_shash_update(shash, p, len);
133                                 kunmap_local(p);
134                                 if (ret < 0)
135                                         return ret;
136                                 maxsize -= len;
137                                 if (maxsize <= 0)
138                                         return 0;
139                                 start += len;
140                                 offset = 0;
141                                 index++;
142                         }
143                 }
144         } while (nr == ARRAY_SIZE(folios));
145         return 0;
146 }
147 
148 /*
149  * Pass the data from an iterator into a hash.
150  */
151 static int cifs_shash_iter(const struct iov_iter *iter, size_t maxsize,
152                            struct shash_desc *shash)
153 {
154         if (maxsize == 0)
155                 return 0;
156 
157         switch (iov_iter_type(iter)) {
158         case ITER_BVEC:
159                 return cifs_shash_bvec(iter, maxsize, shash);
160         case ITER_KVEC:
161                 return cifs_shash_kvec(iter, maxsize, shash);
162         case ITER_XARRAY:
163                 return cifs_shash_xarray(iter, maxsize, shash);
164         default:
165                 pr_err("cifs_shash_iter(%u) unsupported\n", iov_iter_type(iter));
166                 WARN_ON_ONCE(1);
167                 return -EIO;
168         }
169 }
170 
171 int __cifs_calc_signature(struct smb_rqst *rqst,
172                           struct TCP_Server_Info *server, char *signature,
173                           struct shash_desc *shash)
174 {
175         int i;
176         ssize_t rc;
177         struct kvec *iov = rqst->rq_iov;
178         int n_vec = rqst->rq_nvec;
179 
180         /* iov[0] is actual data and not the rfc1002 length for SMB2+ */
181         if (!is_smb1(server)) {
182                 if (iov[0].iov_len <= 4)
183                         return -EIO;
184                 i = 0;
185         } else {
186                 if (n_vec < 2 || iov[0].iov_len != 4)
187                         return -EIO;
188                 i = 1; /* skip rfc1002 length */
189         }
190 
191         for (; i < n_vec; i++) {
192                 if (iov[i].iov_len == 0)
193                         continue;
194                 if (iov[i].iov_base == NULL) {
195                         cifs_dbg(VFS, "null iovec entry\n");
196                         return -EIO;
197                 }
198 
199                 rc = crypto_shash_update(shash,
200                                          iov[i].iov_base, iov[i].iov_len);
201                 if (rc) {
202                         cifs_dbg(VFS, "%s: Could not update with payload\n",
203                                  __func__);
204                         return rc;
205                 }
206         }
207 
208         rc = cifs_shash_iter(&rqst->rq_iter, iov_iter_count(&rqst->rq_iter), shash);
209         if (rc < 0)
210                 return rc;
211 
212         rc = crypto_shash_final(shash, signature);
213         if (rc)
214                 cifs_dbg(VFS, "%s: Could not generate hash\n", __func__);
215 
216         return rc;
217 }
218 
219 /*
220  * Calculate and return the CIFS signature based on the mac key and SMB PDU.
221  * The 16 byte signature must be allocated by the caller. Note we only use the
222  * 1st eight bytes and that the smb header signature field on input contains
223  * the sequence number before this function is called. Also, this function
224  * should be called with the server->srv_mutex held.
225  */
226 static int cifs_calc_signature(struct smb_rqst *rqst,
227                         struct TCP_Server_Info *server, char *signature)
228 {
229         int rc;
230 
231         if (!rqst->rq_iov || !signature || !server)
232                 return -EINVAL;
233 
234         rc = cifs_alloc_hash("md5", &server->secmech.md5);
235         if (rc)
236                 return -1;
237 
238         rc = crypto_shash_init(server->secmech.md5);
239         if (rc) {
240                 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
241                 return rc;
242         }
243 
244         rc = crypto_shash_update(server->secmech.md5,
245                 server->session_key.response, server->session_key.len);
246         if (rc) {
247                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
248                 return rc;
249         }
250 
251         return __cifs_calc_signature(rqst, server, signature, server->secmech.md5);
252 }
253 
254 /* must be called with server->srv_mutex held */
255 int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
256                    __u32 *pexpected_response_sequence_number)
257 {
258         int rc = 0;
259         char smb_signature[20];
260         struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
261 
262         if (rqst->rq_iov[0].iov_len != 4 ||
263             rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
264                 return -EIO;
265 
266         if ((cifs_pdu == NULL) || (server == NULL))
267                 return -EINVAL;
268 
269         spin_lock(&server->srv_lock);
270         if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
271             server->tcpStatus == CifsNeedNegotiate) {
272                 spin_unlock(&server->srv_lock);
273                 return rc;
274         }
275         spin_unlock(&server->srv_lock);
276 
277         if (!server->session_estab) {
278                 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
279                 return rc;
280         }
281 
282         cifs_pdu->Signature.Sequence.SequenceNumber =
283                                 cpu_to_le32(server->sequence_number);
284         cifs_pdu->Signature.Sequence.Reserved = 0;
285 
286         *pexpected_response_sequence_number = ++server->sequence_number;
287         ++server->sequence_number;
288 
289         rc = cifs_calc_signature(rqst, server, smb_signature);
290         if (rc)
291                 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
292         else
293                 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
294 
295         return rc;
296 }
297 
298 int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
299                    __u32 *pexpected_response_sequence)
300 {
301         struct smb_rqst rqst = { .rq_iov = iov,
302                                  .rq_nvec = n_vec };
303 
304         return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
305 }
306 
307 /* must be called with server->srv_mutex held */
308 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
309                   __u32 *pexpected_response_sequence_number)
310 {
311         struct kvec iov[2];
312 
313         iov[0].iov_base = cifs_pdu;
314         iov[0].iov_len = 4;
315         iov[1].iov_base = (char *)cifs_pdu + 4;
316         iov[1].iov_len = be32_to_cpu(cifs_pdu->smb_buf_length);
317 
318         return cifs_sign_smbv(iov, 2, server,
319                               pexpected_response_sequence_number);
320 }
321 
322 int cifs_verify_signature(struct smb_rqst *rqst,
323                           struct TCP_Server_Info *server,
324                           __u32 expected_sequence_number)
325 {
326         unsigned int rc;
327         char server_response_sig[8];
328         char what_we_think_sig_should_be[20];
329         struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
330 
331         if (rqst->rq_iov[0].iov_len != 4 ||
332             rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
333                 return -EIO;
334 
335         if (cifs_pdu == NULL || server == NULL)
336                 return -EINVAL;
337 
338         if (!server->session_estab)
339                 return 0;
340 
341         if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
342                 struct smb_com_lock_req *pSMB =
343                         (struct smb_com_lock_req *)cifs_pdu;
344                 if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
345                         return 0;
346         }
347 
348         /* BB what if signatures are supposed to be on for session but
349            server does not send one? BB */
350 
351         /* Do not need to verify session setups with signature "BSRSPYL "  */
352         if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
353                 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
354                          cifs_pdu->Command);
355 
356         /* save off the origiginal signature so we can modify the smb and check
357                 its signature against what the server sent */
358         memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
359 
360         cifs_pdu->Signature.Sequence.SequenceNumber =
361                                         cpu_to_le32(expected_sequence_number);
362         cifs_pdu->Signature.Sequence.Reserved = 0;
363 
364         cifs_server_lock(server);
365         rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
366         cifs_server_unlock(server);
367 
368         if (rc)
369                 return rc;
370 
371 /*      cifs_dump_mem("what we think it should be: ",
372                       what_we_think_sig_should_be, 16); */
373 
374         if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
375                 return -EACCES;
376         else
377                 return 0;
378 
379 }
380 
381 /* Build a proper attribute value/target info pairs blob.
382  * Fill in netbios and dns domain name and workstation name
383  * and client time (total five av pairs and + one end of fields indicator.
384  * Allocate domain name which gets freed when session struct is deallocated.
385  */
386 static int
387 build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
388 {
389         unsigned int dlen;
390         unsigned int size = 2 * sizeof(struct ntlmssp2_name);
391         char *defdmname = "WORKGROUP";
392         unsigned char *blobptr;
393         struct ntlmssp2_name *attrptr;
394 
395         if (!ses->domainName) {
396                 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
397                 if (!ses->domainName)
398                         return -ENOMEM;
399         }
400 
401         dlen = strlen(ses->domainName);
402 
403         /*
404          * The length of this blob is two times the size of a
405          * structure (av pair) which holds name/size
406          * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
407          * unicode length of a netbios domain name
408          */
409         kfree_sensitive(ses->auth_key.response);
410         ses->auth_key.len = size + 2 * dlen;
411         ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
412         if (!ses->auth_key.response) {
413                 ses->auth_key.len = 0;
414                 return -ENOMEM;
415         }
416 
417         blobptr = ses->auth_key.response;
418         attrptr = (struct ntlmssp2_name *) blobptr;
419 
420         /*
421          * As defined in MS-NTLM 3.3.2, just this av pair field
422          * is sufficient as part of the temp
423          */
424         attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
425         attrptr->length = cpu_to_le16(2 * dlen);
426         blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
427         cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
428 
429         return 0;
430 }
431 
432 /* Server has provided av pairs/target info in the type 2 challenge
433  * packet and we have plucked it and stored within smb session.
434  * We parse that blob here to find netbios domain name to be used
435  * as part of ntlmv2 authentication (in Target String), if not already
436  * specified on the command line.
437  * If this function returns without any error but without fetching
438  * domain name, authentication may fail against some server but
439  * may not fail against other (those who are not very particular
440  * about target string i.e. for some, just user name might suffice.
441  */
442 static int
443 find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
444 {
445         unsigned int attrsize;
446         unsigned int type;
447         unsigned int onesize = sizeof(struct ntlmssp2_name);
448         unsigned char *blobptr;
449         unsigned char *blobend;
450         struct ntlmssp2_name *attrptr;
451 
452         if (!ses->auth_key.len || !ses->auth_key.response)
453                 return 0;
454 
455         blobptr = ses->auth_key.response;
456         blobend = blobptr + ses->auth_key.len;
457 
458         while (blobptr + onesize < blobend) {
459                 attrptr = (struct ntlmssp2_name *) blobptr;
460                 type = le16_to_cpu(attrptr->type);
461                 if (type == NTLMSSP_AV_EOL)
462                         break;
463                 blobptr += 2; /* advance attr type */
464                 attrsize = le16_to_cpu(attrptr->length);
465                 blobptr += 2; /* advance attr size */
466                 if (blobptr + attrsize > blobend)
467                         break;
468                 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
469                         if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
470                                 break;
471                         if (!ses->domainName) {
472                                 ses->domainName =
473                                         kmalloc(attrsize + 1, GFP_KERNEL);
474                                 if (!ses->domainName)
475                                                 return -ENOMEM;
476                                 cifs_from_utf16(ses->domainName,
477                                         (__le16 *)blobptr, attrsize, attrsize,
478                                         nls_cp, NO_MAP_UNI_RSVD);
479                                 break;
480                         }
481                 }
482                 blobptr += attrsize; /* advance attr  value */
483         }
484 
485         return 0;
486 }
487 
488 /* Server has provided av pairs/target info in the type 2 challenge
489  * packet and we have plucked it and stored within smb session.
490  * We parse that blob here to find the server given timestamp
491  * as part of ntlmv2 authentication (or local current time as
492  * default in case of failure)
493  */
494 static __le64
495 find_timestamp(struct cifs_ses *ses)
496 {
497         unsigned int attrsize;
498         unsigned int type;
499         unsigned int onesize = sizeof(struct ntlmssp2_name);
500         unsigned char *blobptr;
501         unsigned char *blobend;
502         struct ntlmssp2_name *attrptr;
503         struct timespec64 ts;
504 
505         if (!ses->auth_key.len || !ses->auth_key.response)
506                 return 0;
507 
508         blobptr = ses->auth_key.response;
509         blobend = blobptr + ses->auth_key.len;
510 
511         while (blobptr + onesize < blobend) {
512                 attrptr = (struct ntlmssp2_name *) blobptr;
513                 type = le16_to_cpu(attrptr->type);
514                 if (type == NTLMSSP_AV_EOL)
515                         break;
516                 blobptr += 2; /* advance attr type */
517                 attrsize = le16_to_cpu(attrptr->length);
518                 blobptr += 2; /* advance attr size */
519                 if (blobptr + attrsize > blobend)
520                         break;
521                 if (type == NTLMSSP_AV_TIMESTAMP) {
522                         if (attrsize == sizeof(u64))
523                                 return *((__le64 *)blobptr);
524                 }
525                 blobptr += attrsize; /* advance attr value */
526         }
527 
528         ktime_get_real_ts64(&ts);
529         return cpu_to_le64(cifs_UnixTimeToNT(ts));
530 }
531 
532 static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
533                             const struct nls_table *nls_cp)
534 {
535         int rc = 0;
536         int len;
537         char nt_hash[CIFS_NTHASH_SIZE];
538         __le16 *user;
539         wchar_t *domain;
540         wchar_t *server;
541 
542         if (!ses->server->secmech.hmacmd5) {
543                 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
544                 return -1;
545         }
546 
547         /* calculate md4 hash of password */
548         E_md4hash(ses->password, nt_hash, nls_cp);
549 
550         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm, nt_hash,
551                                 CIFS_NTHASH_SIZE);
552         if (rc) {
553                 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
554                 return rc;
555         }
556 
557         rc = crypto_shash_init(ses->server->secmech.hmacmd5);
558         if (rc) {
559                 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
560                 return rc;
561         }
562 
563         /* convert ses->user_name to unicode */
564         len = ses->user_name ? strlen(ses->user_name) : 0;
565         user = kmalloc(2 + (len * 2), GFP_KERNEL);
566         if (user == NULL) {
567                 rc = -ENOMEM;
568                 return rc;
569         }
570 
571         if (len) {
572                 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
573                 UniStrupr(user);
574         } else {
575                 *(u16 *)user = 0;
576         }
577 
578         rc = crypto_shash_update(ses->server->secmech.hmacmd5,
579                                 (char *)user, 2 * len);
580         kfree(user);
581         if (rc) {
582                 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
583                 return rc;
584         }
585 
586         /* convert ses->domainName to unicode and uppercase */
587         if (ses->domainName) {
588                 len = strlen(ses->domainName);
589 
590                 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
591                 if (domain == NULL) {
592                         rc = -ENOMEM;
593                         return rc;
594                 }
595                 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
596                                       nls_cp);
597                 rc =
598                 crypto_shash_update(ses->server->secmech.hmacmd5,
599                                         (char *)domain, 2 * len);
600                 kfree(domain);
601                 if (rc) {
602                         cifs_dbg(VFS, "%s: Could not update with domain\n",
603                                  __func__);
604                         return rc;
605                 }
606         } else {
607                 /* We use ses->ip_addr if no domain name available */
608                 len = strlen(ses->ip_addr);
609 
610                 server = kmalloc(2 + (len * 2), GFP_KERNEL);
611                 if (server == NULL) {
612                         rc = -ENOMEM;
613                         return rc;
614                 }
615                 len = cifs_strtoUTF16((__le16 *)server, ses->ip_addr, len,
616                                         nls_cp);
617                 rc =
618                 crypto_shash_update(ses->server->secmech.hmacmd5,
619                                         (char *)server, 2 * len);
620                 kfree(server);
621                 if (rc) {
622                         cifs_dbg(VFS, "%s: Could not update with server\n",
623                                  __func__);
624                         return rc;
625                 }
626         }
627 
628         rc = crypto_shash_final(ses->server->secmech.hmacmd5,
629                                         ntlmv2_hash);
630         if (rc)
631                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
632 
633         return rc;
634 }
635 
636 static int
637 CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
638 {
639         int rc;
640         struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
641             (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
642         unsigned int hash_len;
643 
644         /* The MD5 hash starts at challenge_key.key */
645         hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
646                 offsetof(struct ntlmv2_resp, challenge.key[0]));
647 
648         if (!ses->server->secmech.hmacmd5) {
649                 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
650                 return -1;
651         }
652 
653         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm,
654                                  ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
655         if (rc) {
656                 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
657                          __func__);
658                 return rc;
659         }
660 
661         rc = crypto_shash_init(ses->server->secmech.hmacmd5);
662         if (rc) {
663                 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
664                 return rc;
665         }
666 
667         if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
668                 memcpy(ntlmv2->challenge.key,
669                        ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
670         else
671                 memcpy(ntlmv2->challenge.key,
672                        ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
673         rc = crypto_shash_update(ses->server->secmech.hmacmd5,
674                                  ntlmv2->challenge.key, hash_len);
675         if (rc) {
676                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
677                 return rc;
678         }
679 
680         /* Note that the MD5 digest over writes anon.challenge_key.key */
681         rc = crypto_shash_final(ses->server->secmech.hmacmd5,
682                                 ntlmv2->ntlmv2_hash);
683         if (rc)
684                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
685 
686         return rc;
687 }
688 
689 int
690 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
691 {
692         int rc;
693         int baselen;
694         unsigned int tilen;
695         struct ntlmv2_resp *ntlmv2;
696         char ntlmv2_hash[16];
697         unsigned char *tiblob = NULL; /* target info blob */
698         __le64 rsp_timestamp;
699 
700         if (nls_cp == NULL) {
701                 cifs_dbg(VFS, "%s called with nls_cp==NULL\n", __func__);
702                 return -EINVAL;
703         }
704 
705         if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
706                 if (!ses->domainName) {
707                         if (ses->domainAuto) {
708                                 rc = find_domain_name(ses, nls_cp);
709                                 if (rc) {
710                                         cifs_dbg(VFS, "error %d finding domain name\n",
711                                                  rc);
712                                         goto setup_ntlmv2_rsp_ret;
713                                 }
714                         } else {
715                                 ses->domainName = kstrdup("", GFP_KERNEL);
716                         }
717                 }
718         } else {
719                 rc = build_avpair_blob(ses, nls_cp);
720                 if (rc) {
721                         cifs_dbg(VFS, "error %d building av pair blob\n", rc);
722                         goto setup_ntlmv2_rsp_ret;
723                 }
724         }
725 
726         /* Must be within 5 minutes of the server (or in range +/-2h
727          * in case of Mac OS X), so simply carry over server timestamp
728          * (as Windows 7 does)
729          */
730         rsp_timestamp = find_timestamp(ses);
731 
732         baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
733         tilen = ses->auth_key.len;
734         tiblob = ses->auth_key.response;
735 
736         ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
737         if (!ses->auth_key.response) {
738                 rc = -ENOMEM;
739                 ses->auth_key.len = 0;
740                 goto setup_ntlmv2_rsp_ret;
741         }
742         ses->auth_key.len += baselen;
743 
744         ntlmv2 = (struct ntlmv2_resp *)
745                         (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
746         ntlmv2->blob_signature = cpu_to_le32(0x00000101);
747         ntlmv2->reserved = 0;
748         ntlmv2->time = rsp_timestamp;
749 
750         get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
751         ntlmv2->reserved2 = 0;
752 
753         memcpy(ses->auth_key.response + baselen, tiblob, tilen);
754 
755         cifs_server_lock(ses->server);
756 
757         rc = cifs_alloc_hash("hmac(md5)", &ses->server->secmech.hmacmd5);
758         if (rc) {
759                 goto unlock;
760         }
761 
762         /* calculate ntlmv2_hash */
763         rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
764         if (rc) {
765                 cifs_dbg(VFS, "Could not get v2 hash rc %d\n", rc);
766                 goto unlock;
767         }
768 
769         /* calculate first part of the client response (CR1) */
770         rc = CalcNTLMv2_response(ses, ntlmv2_hash);
771         if (rc) {
772                 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
773                 goto unlock;
774         }
775 
776         /* now calculate the session key for NTLMv2 */
777         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5->tfm,
778                 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
779         if (rc) {
780                 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
781                          __func__);
782                 goto unlock;
783         }
784 
785         rc = crypto_shash_init(ses->server->secmech.hmacmd5);
786         if (rc) {
787                 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
788                 goto unlock;
789         }
790 
791         rc = crypto_shash_update(ses->server->secmech.hmacmd5,
792                 ntlmv2->ntlmv2_hash,
793                 CIFS_HMAC_MD5_HASH_SIZE);
794         if (rc) {
795                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
796                 goto unlock;
797         }
798 
799         rc = crypto_shash_final(ses->server->secmech.hmacmd5,
800                 ses->auth_key.response);
801         if (rc)
802                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
803 
804 unlock:
805         cifs_server_unlock(ses->server);
806 setup_ntlmv2_rsp_ret:
807         kfree_sensitive(tiblob);
808 
809         return rc;
810 }
811 
812 int
813 calc_seckey(struct cifs_ses *ses)
814 {
815         unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
816         struct arc4_ctx *ctx_arc4;
817 
818         if (fips_enabled)
819                 return -ENODEV;
820 
821         get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
822 
823         ctx_arc4 = kmalloc(sizeof(*ctx_arc4), GFP_KERNEL);
824         if (!ctx_arc4) {
825                 cifs_dbg(VFS, "Could not allocate arc4 context\n");
826                 return -ENOMEM;
827         }
828 
829         cifs_arc4_setkey(ctx_arc4, ses->auth_key.response, CIFS_SESS_KEY_SIZE);
830         cifs_arc4_crypt(ctx_arc4, ses->ntlmssp->ciphertext, sec_key,
831                         CIFS_CPHTXT_SIZE);
832 
833         /* make secondary_key/nonce as session key */
834         memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
835         /* and make len as that of session key only */
836         ses->auth_key.len = CIFS_SESS_KEY_SIZE;
837 
838         memzero_explicit(sec_key, CIFS_SESS_KEY_SIZE);
839         kfree_sensitive(ctx_arc4);
840         return 0;
841 }
842 
843 void
844 cifs_crypto_secmech_release(struct TCP_Server_Info *server)
845 {
846         cifs_free_hash(&server->secmech.aes_cmac);
847         cifs_free_hash(&server->secmech.hmacsha256);
848         cifs_free_hash(&server->secmech.md5);
849         cifs_free_hash(&server->secmech.sha512);
850         cifs_free_hash(&server->secmech.hmacmd5);
851 
852         if (server->secmech.enc) {
853                 crypto_free_aead(server->secmech.enc);
854                 server->secmech.enc = NULL;
855         }
856 
857         if (server->secmech.dec) {
858                 crypto_free_aead(server->secmech.dec);
859                 server->secmech.dec = NULL;
860         }
861 }
862 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

sflogo.php