cifsencrypt.c 22 KB

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  1. /*
  2. * fs/cifs/cifsencrypt.c
  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. * This library is free software; you can redistribute it and/or modify
  11. * it under the terms of the GNU Lesser General Public License as published
  12. * by the Free Software Foundation; either version 2.1 of the License, or
  13. * (at your option) any later version.
  14. *
  15. * This library is distributed in the hope that it will be useful,
  16. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
  18. * the GNU Lesser General Public License for more details.
  19. *
  20. * You should have received a copy of the GNU Lesser General Public License
  21. * along with this library; if not, write to the Free Software
  22. * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23. */
  24. #include <linux/fs.h>
  25. #include <linux/slab.h>
  26. #include "cifspdu.h"
  27. #include "cifsglob.h"
  28. #include "cifs_debug.h"
  29. #include "cifs_unicode.h"
  30. #include "cifsproto.h"
  31. #include "ntlmssp.h"
  32. #include <linux/ctype.h>
  33. #include <linux/random.h>
  34. #include <linux/highmem.h>
  35. static int
  36. cifs_crypto_shash_md5_allocate(struct TCP_Server_Info *server)
  37. {
  38. int rc;
  39. unsigned int size;
  40. if (server->secmech.sdescmd5 != NULL)
  41. return 0; /* already allocated */
  42. server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
  43. if (IS_ERR(server->secmech.md5)) {
  44. cifs_dbg(VFS, "could not allocate crypto md5\n");
  45. rc = PTR_ERR(server->secmech.md5);
  46. server->secmech.md5 = NULL;
  47. return rc;
  48. }
  49. size = sizeof(struct shash_desc) +
  50. crypto_shash_descsize(server->secmech.md5);
  51. server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
  52. if (!server->secmech.sdescmd5) {
  53. crypto_free_shash(server->secmech.md5);
  54. server->secmech.md5 = NULL;
  55. return -ENOMEM;
  56. }
  57. server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
  58. server->secmech.sdescmd5->shash.flags = 0x0;
  59. return 0;
  60. }
  61. /*
  62. * Calculate and return the CIFS signature based on the mac key and SMB PDU.
  63. * The 16 byte signature must be allocated by the caller. Note we only use the
  64. * 1st eight bytes and that the smb header signature field on input contains
  65. * the sequence number before this function is called. Also, this function
  66. * should be called with the server->srv_mutex held.
  67. */
  68. static int cifs_calc_signature(struct smb_rqst *rqst,
  69. struct TCP_Server_Info *server, char *signature)
  70. {
  71. int i;
  72. int rc;
  73. struct kvec *iov = rqst->rq_iov;
  74. int n_vec = rqst->rq_nvec;
  75. if (iov == NULL || signature == NULL || server == NULL)
  76. return -EINVAL;
  77. if (!server->secmech.sdescmd5) {
  78. rc = cifs_crypto_shash_md5_allocate(server);
  79. if (rc) {
  80. cifs_dbg(VFS, "%s: Can't alloc md5 crypto\n", __func__);
  81. return -1;
  82. }
  83. }
  84. rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
  85. if (rc) {
  86. cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
  87. return rc;
  88. }
  89. rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
  90. server->session_key.response, server->session_key.len);
  91. if (rc) {
  92. cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
  93. return rc;
  94. }
  95. for (i = 0; i < n_vec; i++) {
  96. if (iov[i].iov_len == 0)
  97. continue;
  98. if (iov[i].iov_base == NULL) {
  99. cifs_dbg(VFS, "null iovec entry\n");
  100. return -EIO;
  101. }
  102. /* The first entry includes a length field (which does not get
  103. signed that occupies the first 4 bytes before the header */
  104. if (i == 0) {
  105. if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
  106. break; /* nothing to sign or corrupt header */
  107. rc =
  108. crypto_shash_update(&server->secmech.sdescmd5->shash,
  109. iov[i].iov_base + 4, iov[i].iov_len - 4);
  110. } else {
  111. rc =
  112. crypto_shash_update(&server->secmech.sdescmd5->shash,
  113. iov[i].iov_base, iov[i].iov_len);
  114. }
  115. if (rc) {
  116. cifs_dbg(VFS, "%s: Could not update with payload\n",
  117. __func__);
  118. return rc;
  119. }
  120. }
  121. /* now hash over the rq_pages array */
  122. for (i = 0; i < rqst->rq_npages; i++) {
  123. struct kvec p_iov;
  124. cifs_rqst_page_to_kvec(rqst, i, &p_iov);
  125. crypto_shash_update(&server->secmech.sdescmd5->shash,
  126. p_iov.iov_base, p_iov.iov_len);
  127. kunmap(rqst->rq_pages[i]);
  128. }
  129. rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
  130. if (rc)
  131. cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
  132. return rc;
  133. }
  134. /* must be called with server->srv_mutex held */
  135. int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
  136. __u32 *pexpected_response_sequence_number)
  137. {
  138. int rc = 0;
  139. char smb_signature[20];
  140. struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
  141. if ((cifs_pdu == NULL) || (server == NULL))
  142. return -EINVAL;
  143. if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
  144. server->tcpStatus == CifsNeedNegotiate)
  145. return rc;
  146. if (!server->session_estab) {
  147. memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
  148. return rc;
  149. }
  150. cifs_pdu->Signature.Sequence.SequenceNumber =
  151. cpu_to_le32(server->sequence_number);
  152. cifs_pdu->Signature.Sequence.Reserved = 0;
  153. *pexpected_response_sequence_number = ++server->sequence_number;
  154. ++server->sequence_number;
  155. rc = cifs_calc_signature(rqst, server, smb_signature);
  156. if (rc)
  157. memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
  158. else
  159. memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
  160. return rc;
  161. }
  162. int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
  163. __u32 *pexpected_response_sequence)
  164. {
  165. struct smb_rqst rqst = { .rq_iov = iov,
  166. .rq_nvec = n_vec };
  167. return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
  168. }
  169. /* must be called with server->srv_mutex held */
  170. int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
  171. __u32 *pexpected_response_sequence_number)
  172. {
  173. struct kvec iov;
  174. iov.iov_base = cifs_pdu;
  175. iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
  176. return cifs_sign_smbv(&iov, 1, server,
  177. pexpected_response_sequence_number);
  178. }
  179. int cifs_verify_signature(struct smb_rqst *rqst,
  180. struct TCP_Server_Info *server,
  181. __u32 expected_sequence_number)
  182. {
  183. unsigned int rc;
  184. char server_response_sig[8];
  185. char what_we_think_sig_should_be[20];
  186. struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
  187. if (cifs_pdu == NULL || server == NULL)
  188. return -EINVAL;
  189. if (!server->session_estab)
  190. return 0;
  191. if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
  192. struct smb_com_lock_req *pSMB =
  193. (struct smb_com_lock_req *)cifs_pdu;
  194. if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
  195. return 0;
  196. }
  197. /* BB what if signatures are supposed to be on for session but
  198. server does not send one? BB */
  199. /* Do not need to verify session setups with signature "BSRSPYL " */
  200. if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
  201. cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
  202. cifs_pdu->Command);
  203. /* save off the origiginal signature so we can modify the smb and check
  204. its signature against what the server sent */
  205. memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
  206. cifs_pdu->Signature.Sequence.SequenceNumber =
  207. cpu_to_le32(expected_sequence_number);
  208. cifs_pdu->Signature.Sequence.Reserved = 0;
  209. mutex_lock(&server->srv_mutex);
  210. rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
  211. mutex_unlock(&server->srv_mutex);
  212. if (rc)
  213. return rc;
  214. /* cifs_dump_mem("what we think it should be: ",
  215. what_we_think_sig_should_be, 16); */
  216. if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
  217. return -EACCES;
  218. else
  219. return 0;
  220. }
  221. /* first calculate 24 bytes ntlm response and then 16 byte session key */
  222. int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
  223. {
  224. int rc = 0;
  225. unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
  226. char temp_key[CIFS_SESS_KEY_SIZE];
  227. if (!ses)
  228. return -EINVAL;
  229. ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
  230. if (!ses->auth_key.response)
  231. return -ENOMEM;
  232. ses->auth_key.len = temp_len;
  233. rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
  234. ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
  235. if (rc) {
  236. cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
  237. __func__, rc);
  238. return rc;
  239. }
  240. rc = E_md4hash(ses->password, temp_key, nls_cp);
  241. if (rc) {
  242. cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
  243. __func__, rc);
  244. return rc;
  245. }
  246. rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
  247. if (rc)
  248. cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
  249. __func__, rc);
  250. return rc;
  251. }
  252. #ifdef CONFIG_CIFS_WEAK_PW_HASH
  253. int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
  254. char *lnm_session_key)
  255. {
  256. int i;
  257. int rc;
  258. char password_with_pad[CIFS_ENCPWD_SIZE];
  259. memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
  260. if (password)
  261. strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
  262. if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
  263. memcpy(lnm_session_key, password_with_pad,
  264. CIFS_ENCPWD_SIZE);
  265. return 0;
  266. }
  267. /* calculate old style session key */
  268. /* calling toupper is less broken than repeatedly
  269. calling nls_toupper would be since that will never
  270. work for UTF8, but neither handles multibyte code pages
  271. but the only alternative would be converting to UCS-16 (Unicode)
  272. (using a routine something like UniStrupr) then
  273. uppercasing and then converting back from Unicode - which
  274. would only worth doing it if we knew it were utf8. Basically
  275. utf8 and other multibyte codepages each need their own strupper
  276. function since a byte at a time will ont work. */
  277. for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
  278. password_with_pad[i] = toupper(password_with_pad[i]);
  279. rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
  280. return rc;
  281. }
  282. #endif /* CIFS_WEAK_PW_HASH */
  283. /* Build a proper attribute value/target info pairs blob.
  284. * Fill in netbios and dns domain name and workstation name
  285. * and client time (total five av pairs and + one end of fields indicator.
  286. * Allocate domain name which gets freed when session struct is deallocated.
  287. */
  288. static int
  289. build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
  290. {
  291. unsigned int dlen;
  292. unsigned int size = 2 * sizeof(struct ntlmssp2_name);
  293. char *defdmname = "WORKGROUP";
  294. unsigned char *blobptr;
  295. struct ntlmssp2_name *attrptr;
  296. if (!ses->domainName) {
  297. ses->domainName = kstrdup(defdmname, GFP_KERNEL);
  298. if (!ses->domainName)
  299. return -ENOMEM;
  300. }
  301. dlen = strlen(ses->domainName);
  302. /*
  303. * The length of this blob is two times the size of a
  304. * structure (av pair) which holds name/size
  305. * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
  306. * unicode length of a netbios domain name
  307. */
  308. ses->auth_key.len = size + 2 * dlen;
  309. ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
  310. if (!ses->auth_key.response) {
  311. ses->auth_key.len = 0;
  312. return -ENOMEM;
  313. }
  314. blobptr = ses->auth_key.response;
  315. attrptr = (struct ntlmssp2_name *) blobptr;
  316. /*
  317. * As defined in MS-NTLM 3.3.2, just this av pair field
  318. * is sufficient as part of the temp
  319. */
  320. attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
  321. attrptr->length = cpu_to_le16(2 * dlen);
  322. blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
  323. cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
  324. return 0;
  325. }
  326. /* Server has provided av pairs/target info in the type 2 challenge
  327. * packet and we have plucked it and stored within smb session.
  328. * We parse that blob here to find netbios domain name to be used
  329. * as part of ntlmv2 authentication (in Target String), if not already
  330. * specified on the command line.
  331. * If this function returns without any error but without fetching
  332. * domain name, authentication may fail against some server but
  333. * may not fail against other (those who are not very particular
  334. * about target string i.e. for some, just user name might suffice.
  335. */
  336. static int
  337. find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
  338. {
  339. unsigned int attrsize;
  340. unsigned int type;
  341. unsigned int onesize = sizeof(struct ntlmssp2_name);
  342. unsigned char *blobptr;
  343. unsigned char *blobend;
  344. struct ntlmssp2_name *attrptr;
  345. if (!ses->auth_key.len || !ses->auth_key.response)
  346. return 0;
  347. blobptr = ses->auth_key.response;
  348. blobend = blobptr + ses->auth_key.len;
  349. while (blobptr + onesize < blobend) {
  350. attrptr = (struct ntlmssp2_name *) blobptr;
  351. type = le16_to_cpu(attrptr->type);
  352. if (type == NTLMSSP_AV_EOL)
  353. break;
  354. blobptr += 2; /* advance attr type */
  355. attrsize = le16_to_cpu(attrptr->length);
  356. blobptr += 2; /* advance attr size */
  357. if (blobptr + attrsize > blobend)
  358. break;
  359. if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
  360. if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
  361. break;
  362. if (!ses->domainName) {
  363. ses->domainName =
  364. kmalloc(attrsize + 1, GFP_KERNEL);
  365. if (!ses->domainName)
  366. return -ENOMEM;
  367. cifs_from_utf16(ses->domainName,
  368. (__le16 *)blobptr, attrsize, attrsize,
  369. nls_cp, NO_MAP_UNI_RSVD);
  370. break;
  371. }
  372. }
  373. blobptr += attrsize; /* advance attr value */
  374. }
  375. return 0;
  376. }
  377. static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
  378. const struct nls_table *nls_cp)
  379. {
  380. int rc = 0;
  381. int len;
  382. char nt_hash[CIFS_NTHASH_SIZE];
  383. __le16 *user;
  384. wchar_t *domain;
  385. wchar_t *server;
  386. if (!ses->server->secmech.sdeschmacmd5) {
  387. cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
  388. return -1;
  389. }
  390. /* calculate md4 hash of password */
  391. E_md4hash(ses->password, nt_hash, nls_cp);
  392. rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
  393. CIFS_NTHASH_SIZE);
  394. if (rc) {
  395. cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
  396. return rc;
  397. }
  398. rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
  399. if (rc) {
  400. cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
  401. return rc;
  402. }
  403. /* convert ses->user_name to unicode */
  404. len = ses->user_name ? strlen(ses->user_name) : 0;
  405. user = kmalloc(2 + (len * 2), GFP_KERNEL);
  406. if (user == NULL) {
  407. rc = -ENOMEM;
  408. return rc;
  409. }
  410. if (len) {
  411. len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
  412. UniStrupr(user);
  413. } else {
  414. memset(user, '\0', 2);
  415. }
  416. rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
  417. (char *)user, 2 * len);
  418. kfree(user);
  419. if (rc) {
  420. cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
  421. return rc;
  422. }
  423. /* convert ses->domainName to unicode and uppercase */
  424. if (ses->domainName) {
  425. len = strlen(ses->domainName);
  426. domain = kmalloc(2 + (len * 2), GFP_KERNEL);
  427. if (domain == NULL) {
  428. rc = -ENOMEM;
  429. return rc;
  430. }
  431. len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
  432. nls_cp);
  433. rc =
  434. crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
  435. (char *)domain, 2 * len);
  436. kfree(domain);
  437. if (rc) {
  438. cifs_dbg(VFS, "%s: Could not update with domain\n",
  439. __func__);
  440. return rc;
  441. }
  442. } else {
  443. /* We use ses->serverName if no domain name available */
  444. len = strlen(ses->serverName);
  445. server = kmalloc(2 + (len * 2), GFP_KERNEL);
  446. if (server == NULL) {
  447. rc = -ENOMEM;
  448. return rc;
  449. }
  450. len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
  451. nls_cp);
  452. rc =
  453. crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
  454. (char *)server, 2 * len);
  455. kfree(server);
  456. if (rc) {
  457. cifs_dbg(VFS, "%s: Could not update with server\n",
  458. __func__);
  459. return rc;
  460. }
  461. }
  462. rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
  463. ntlmv2_hash);
  464. if (rc)
  465. cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
  466. return rc;
  467. }
  468. static int
  469. CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
  470. {
  471. int rc;
  472. struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
  473. (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
  474. unsigned int hash_len;
  475. /* The MD5 hash starts at challenge_key.key */
  476. hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
  477. offsetof(struct ntlmv2_resp, challenge.key[0]));
  478. if (!ses->server->secmech.sdeschmacmd5) {
  479. cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
  480. return -1;
  481. }
  482. rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
  483. ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
  484. if (rc) {
  485. cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
  486. __func__);
  487. return rc;
  488. }
  489. rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
  490. if (rc) {
  491. cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
  492. return rc;
  493. }
  494. if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
  495. memcpy(ntlmv2->challenge.key,
  496. ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
  497. else
  498. memcpy(ntlmv2->challenge.key,
  499. ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
  500. rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
  501. ntlmv2->challenge.key, hash_len);
  502. if (rc) {
  503. cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
  504. return rc;
  505. }
  506. /* Note that the MD5 digest over writes anon.challenge_key.key */
  507. rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
  508. ntlmv2->ntlmv2_hash);
  509. if (rc)
  510. cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
  511. return rc;
  512. }
  513. static int crypto_hmacmd5_alloc(struct TCP_Server_Info *server)
  514. {
  515. int rc;
  516. unsigned int size;
  517. /* check if already allocated */
  518. if (server->secmech.sdeschmacmd5)
  519. return 0;
  520. server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
  521. if (IS_ERR(server->secmech.hmacmd5)) {
  522. cifs_dbg(VFS, "could not allocate crypto hmacmd5\n");
  523. rc = PTR_ERR(server->secmech.hmacmd5);
  524. server->secmech.hmacmd5 = NULL;
  525. return rc;
  526. }
  527. size = sizeof(struct shash_desc) +
  528. crypto_shash_descsize(server->secmech.hmacmd5);
  529. server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
  530. if (!server->secmech.sdeschmacmd5) {
  531. crypto_free_shash(server->secmech.hmacmd5);
  532. server->secmech.hmacmd5 = NULL;
  533. return -ENOMEM;
  534. }
  535. server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
  536. server->secmech.sdeschmacmd5->shash.flags = 0x0;
  537. return 0;
  538. }
  539. int
  540. setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
  541. {
  542. int rc;
  543. int baselen;
  544. unsigned int tilen;
  545. struct ntlmv2_resp *ntlmv2;
  546. char ntlmv2_hash[16];
  547. unsigned char *tiblob = NULL; /* target info blob */
  548. if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
  549. if (!ses->domainName) {
  550. rc = find_domain_name(ses, nls_cp);
  551. if (rc) {
  552. cifs_dbg(VFS, "error %d finding domain name\n",
  553. rc);
  554. goto setup_ntlmv2_rsp_ret;
  555. }
  556. }
  557. } else {
  558. rc = build_avpair_blob(ses, nls_cp);
  559. if (rc) {
  560. cifs_dbg(VFS, "error %d building av pair blob\n", rc);
  561. goto setup_ntlmv2_rsp_ret;
  562. }
  563. }
  564. baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
  565. tilen = ses->auth_key.len;
  566. tiblob = ses->auth_key.response;
  567. ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
  568. if (!ses->auth_key.response) {
  569. rc = ENOMEM;
  570. ses->auth_key.len = 0;
  571. goto setup_ntlmv2_rsp_ret;
  572. }
  573. ses->auth_key.len += baselen;
  574. ntlmv2 = (struct ntlmv2_resp *)
  575. (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
  576. ntlmv2->blob_signature = cpu_to_le32(0x00000101);
  577. ntlmv2->reserved = 0;
  578. /* Must be within 5 minutes of the server */
  579. ntlmv2->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
  580. get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
  581. ntlmv2->reserved2 = 0;
  582. memcpy(ses->auth_key.response + baselen, tiblob, tilen);
  583. rc = crypto_hmacmd5_alloc(ses->server);
  584. if (rc) {
  585. cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
  586. goto setup_ntlmv2_rsp_ret;
  587. }
  588. /* calculate ntlmv2_hash */
  589. rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
  590. if (rc) {
  591. cifs_dbg(VFS, "could not get v2 hash rc %d\n", rc);
  592. goto setup_ntlmv2_rsp_ret;
  593. }
  594. /* calculate first part of the client response (CR1) */
  595. rc = CalcNTLMv2_response(ses, ntlmv2_hash);
  596. if (rc) {
  597. cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
  598. goto setup_ntlmv2_rsp_ret;
  599. }
  600. /* now calculate the session key for NTLMv2 */
  601. rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
  602. ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
  603. if (rc) {
  604. cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
  605. __func__);
  606. goto setup_ntlmv2_rsp_ret;
  607. }
  608. rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
  609. if (rc) {
  610. cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
  611. goto setup_ntlmv2_rsp_ret;
  612. }
  613. rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
  614. ntlmv2->ntlmv2_hash,
  615. CIFS_HMAC_MD5_HASH_SIZE);
  616. if (rc) {
  617. cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
  618. goto setup_ntlmv2_rsp_ret;
  619. }
  620. rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
  621. ses->auth_key.response);
  622. if (rc)
  623. cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
  624. setup_ntlmv2_rsp_ret:
  625. kfree(tiblob);
  626. return rc;
  627. }
  628. int
  629. calc_seckey(struct cifs_ses *ses)
  630. {
  631. int rc;
  632. struct crypto_blkcipher *tfm_arc4;
  633. struct scatterlist sgin, sgout;
  634. struct blkcipher_desc desc;
  635. unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
  636. get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
  637. tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
  638. if (IS_ERR(tfm_arc4)) {
  639. rc = PTR_ERR(tfm_arc4);
  640. cifs_dbg(VFS, "could not allocate crypto API arc4\n");
  641. return rc;
  642. }
  643. desc.tfm = tfm_arc4;
  644. rc = crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,
  645. CIFS_SESS_KEY_SIZE);
  646. if (rc) {
  647. cifs_dbg(VFS, "%s: Could not set response as a key\n",
  648. __func__);
  649. return rc;
  650. }
  651. sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
  652. sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
  653. rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
  654. if (rc) {
  655. cifs_dbg(VFS, "could not encrypt session key rc: %d\n", rc);
  656. crypto_free_blkcipher(tfm_arc4);
  657. return rc;
  658. }
  659. /* make secondary_key/nonce as session key */
  660. memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
  661. /* and make len as that of session key only */
  662. ses->auth_key.len = CIFS_SESS_KEY_SIZE;
  663. crypto_free_blkcipher(tfm_arc4);
  664. return rc;
  665. }
  666. void
  667. cifs_crypto_shash_release(struct TCP_Server_Info *server)
  668. {
  669. if (server->secmech.cmacaes) {
  670. crypto_free_shash(server->secmech.cmacaes);
  671. server->secmech.cmacaes = NULL;
  672. }
  673. if (server->secmech.hmacsha256) {
  674. crypto_free_shash(server->secmech.hmacsha256);
  675. server->secmech.hmacsha256 = NULL;
  676. }
  677. if (server->secmech.md5) {
  678. crypto_free_shash(server->secmech.md5);
  679. server->secmech.md5 = NULL;
  680. }
  681. if (server->secmech.hmacmd5) {
  682. crypto_free_shash(server->secmech.hmacmd5);
  683. server->secmech.hmacmd5 = NULL;
  684. }
  685. kfree(server->secmech.sdesccmacaes);
  686. server->secmech.sdesccmacaes = NULL;
  687. kfree(server->secmech.sdeschmacsha256);
  688. server->secmech.sdeschmacsha256 = NULL;
  689. kfree(server->secmech.sdeschmacmd5);
  690. server->secmech.sdeschmacmd5 = NULL;
  691. kfree(server->secmech.sdescmd5);
  692. server->secmech.sdescmd5 = NULL;
  693. }