4 * SMB/CIFS session setup handling routines
6 * Copyright (c) International Business Machines Corp., 2006, 2009
7 * Author(s): Steve French (sfrench@us.ibm.com)
9 * This library is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as published
11 * by the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
17 * the GNU Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this library; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 #include "cifsproto.h"
27 #include "cifs_unicode.h"
28 #include "cifs_debug.h"
31 #include <linux/utsname.h>
32 #include "cifs_spnego.h"
34 extern void SMBNTencrypt(unsigned char *passwd, unsigned char *c8,
37 /* Checks if this is the first smb session to be reconnected after
38 the socket has been reestablished (so we know whether to use vc 0).
39 Called while holding the cifs_tcp_ses_lock, so do not block */
40 static bool is_first_ses_reconnect(struct cifsSesInfo *ses)
42 struct list_head *tmp;
43 struct cifsSesInfo *tmp_ses;
45 list_for_each(tmp, &ses->server->smb_ses_list) {
46 tmp_ses = list_entry(tmp, struct cifsSesInfo,
48 if (tmp_ses->need_reconnect == false)
51 /* could not find a session that was already connected,
52 this must be the first one we are reconnecting */
57 * vc number 0 is treated specially by some servers, and should be the
58 * first one we request. After that we can use vcnumbers up to maxvcs,
59 * one for each smb session (some Windows versions set maxvcs incorrectly
60 * so maxvc=1 can be ignored). If we have too many vcs, we can reuse
61 * any vc but zero (some servers reset the connection on vcnum zero)
64 static __le16 get_next_vcnum(struct cifsSesInfo *ses)
67 struct list_head *tmp;
68 struct cifsSesInfo *tmp_ses;
69 __u16 max_vcs = ses->server->max_vcs;
71 int free_vc_found = 0;
73 /* Quoting the MS-SMB specification: "Windows-based SMB servers set this
74 field to one but do not enforce this limit, which allows an SMB client
75 to establish more virtual circuits than allowed by this value ... but
76 other server implementations can enforce this limit." */
80 write_lock(&cifs_tcp_ses_lock);
81 if ((ses->need_reconnect) && is_first_ses_reconnect(ses))
82 goto get_vc_num_exit; /* vcnum will be zero */
83 for (i = ses->server->srv_count - 1; i < max_vcs; i++) {
84 if (i == 0) /* this is the only connection, use vc 0 */
89 list_for_each(tmp, &ses->server->smb_ses_list) {
90 tmp_ses = list_entry(tmp, struct cifsSesInfo,
92 if (tmp_ses->vcnum == i) {
94 break; /* found duplicate, try next vcnum */
98 break; /* we found a vcnumber that will work - use it */
102 vcnum = 0; /* for most common case, ie if one smb session, use
103 vc zero. Also for case when no free vcnum, zero
104 is safest to send (some clients only send zero) */
105 else if (free_vc_found == 0)
106 vcnum = 1; /* we can not reuse vc=0 safely, since some servers
107 reset all uids on that, but 1 is ok. */
112 write_unlock(&cifs_tcp_ses_lock);
114 return cpu_to_le16(vcnum);
117 static __u32 cifs_ssetup_hdr(struct cifsSesInfo *ses, SESSION_SETUP_ANDX *pSMB)
119 __u32 capabilities = 0;
121 /* init fields common to all four types of SessSetup */
122 /* Note that offsets for first seven fields in req struct are same */
123 /* in CIFS Specs so does not matter which of 3 forms of struct */
124 /* that we use in next few lines */
125 /* Note that header is initialized to zero in header_assemble */
126 pSMB->req.AndXCommand = 0xFF;
127 pSMB->req.MaxBufferSize = cpu_to_le16(ses->server->maxBuf);
128 pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);
129 pSMB->req.VcNumber = get_next_vcnum(ses);
131 /* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
133 /* BB verify whether signing required on neg or just on auth frame
136 capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
137 CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
139 if (ses->server->secMode &
140 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
141 pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
143 if (ses->capabilities & CAP_UNICODE) {
144 pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
145 capabilities |= CAP_UNICODE;
147 if (ses->capabilities & CAP_STATUS32) {
148 pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
149 capabilities |= CAP_STATUS32;
151 if (ses->capabilities & CAP_DFS) {
152 pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
153 capabilities |= CAP_DFS;
155 if (ses->capabilities & CAP_UNIX)
156 capabilities |= CAP_UNIX;
162 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
164 char *bcc_ptr = *pbcc_area;
167 /* Copy OS version */
168 bytes_ret = cifs_strtoUCS((__le16 *)bcc_ptr, "Linux version ", 32,
170 bcc_ptr += 2 * bytes_ret;
171 bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, init_utsname()->release,
173 bcc_ptr += 2 * bytes_ret;
174 bcc_ptr += 2; /* trailing null */
176 bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
178 bcc_ptr += 2 * bytes_ret;
179 bcc_ptr += 2; /* trailing null */
181 *pbcc_area = bcc_ptr;
184 static void unicode_domain_string(char **pbcc_area, struct cifsSesInfo *ses,
185 const struct nls_table *nls_cp)
187 char *bcc_ptr = *pbcc_area;
191 if (ses->domainName == NULL) {
192 /* Sending null domain better than using a bogus domain name (as
193 we did briefly in 2.6.18) since server will use its default */
198 bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->domainName,
200 bcc_ptr += 2 * bytes_ret;
201 bcc_ptr += 2; /* account for null terminator */
203 *pbcc_area = bcc_ptr;
207 static void unicode_ssetup_strings(char **pbcc_area, struct cifsSesInfo *ses,
208 const struct nls_table *nls_cp)
210 char *bcc_ptr = *pbcc_area;
213 /* BB FIXME add check that strings total less
214 than 335 or will need to send them as arrays */
216 /* unicode strings, must be word aligned before the call */
217 /* if ((long) bcc_ptr % 2) {
222 if (ses->userName == NULL) {
223 /* null user mount */
226 } else { /* 300 should be long enough for any conceivable user name */
227 bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->userName,
230 bcc_ptr += 2 * bytes_ret;
231 bcc_ptr += 2; /* account for null termination */
233 unicode_domain_string(&bcc_ptr, ses, nls_cp);
234 unicode_oslm_strings(&bcc_ptr, nls_cp);
236 *pbcc_area = bcc_ptr;
239 static void ascii_ssetup_strings(char **pbcc_area, struct cifsSesInfo *ses,
240 const struct nls_table *nls_cp)
242 char *bcc_ptr = *pbcc_area;
245 /* BB what about null user mounts - check that we do this BB */
247 if (ses->userName == NULL) {
248 /* BB what about null user mounts - check that we do this BB */
249 } else { /* 300 should be long enough for any conceivable user name */
250 strncpy(bcc_ptr, ses->userName, 300);
252 /* BB improve check for overflow */
253 bcc_ptr += strnlen(ses->userName, 300);
255 bcc_ptr++; /* account for null termination */
259 if (ses->domainName != NULL) {
260 strncpy(bcc_ptr, ses->domainName, 256);
261 bcc_ptr += strnlen(ses->domainName, 256);
262 } /* else we will send a null domain name
263 so the server will default to its own domain */
267 /* BB check for overflow here */
269 strcpy(bcc_ptr, "Linux version ");
270 bcc_ptr += strlen("Linux version ");
271 strcpy(bcc_ptr, init_utsname()->release);
272 bcc_ptr += strlen(init_utsname()->release) + 1;
274 strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
275 bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
277 *pbcc_area = bcc_ptr;
281 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifsSesInfo *ses,
282 const struct nls_table *nls_cp)
285 char *data = *pbcc_area;
287 cFYI(1, ("bleft %d", bleft));
290 * Windows servers do not always double null terminate their final
291 * Unicode string. Check to see if there are an uneven number of bytes
292 * left. If so, then add an extra NULL pad byte to the end of the
295 * See section 2.7.2 in "Implementing CIFS" for details
302 kfree(ses->serverOS);
303 ses->serverOS = cifs_strndup_from_ucs(data, bleft, true, nls_cp);
304 cFYI(1, ("serverOS=%s", ses->serverOS));
305 len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
311 kfree(ses->serverNOS);
312 ses->serverNOS = cifs_strndup_from_ucs(data, bleft, true, nls_cp);
313 cFYI(1, ("serverNOS=%s", ses->serverNOS));
314 len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
320 kfree(ses->serverDomain);
321 ses->serverDomain = cifs_strndup_from_ucs(data, bleft, true, nls_cp);
322 cFYI(1, ("serverDomain=%s", ses->serverDomain));
327 static int decode_ascii_ssetup(char **pbcc_area, int bleft,
328 struct cifsSesInfo *ses,
329 const struct nls_table *nls_cp)
333 char *bcc_ptr = *pbcc_area;
335 cFYI(1, ("decode sessetup ascii. bleft %d", bleft));
337 len = strnlen(bcc_ptr, bleft);
341 kfree(ses->serverOS);
343 ses->serverOS = kzalloc(len + 1, GFP_KERNEL);
345 strncpy(ses->serverOS, bcc_ptr, len);
346 if (strncmp(ses->serverOS, "OS/2", 4) == 0) {
347 cFYI(1, ("OS/2 server"));
348 ses->flags |= CIFS_SES_OS2;
354 len = strnlen(bcc_ptr, bleft);
358 kfree(ses->serverNOS);
360 ses->serverNOS = kzalloc(len + 1, GFP_KERNEL);
362 strncpy(ses->serverNOS, bcc_ptr, len);
367 len = strnlen(bcc_ptr, bleft);
371 /* No domain field in LANMAN case. Domain is
372 returned by old servers in the SMB negprot response */
373 /* BB For newer servers which do not support Unicode,
374 but thus do return domain here we could add parsing
375 for it later, but it is not very important */
376 cFYI(1, ("ascii: bytes left %d", bleft));
382 CIFS_SessSetup(unsigned int xid, struct cifsSesInfo *ses, int first_time,
383 const struct nls_table *nls_cp)
387 struct smb_hdr *smb_buf;
390 SESSION_SETUP_ANDX *pSMB;
395 enum securityEnum type;
398 struct key *spnego_key = NULL;
403 type = ses->server->secType;
405 cFYI(1, ("sess setup type %d", type));
406 if (type == LANMAN) {
407 #ifndef CONFIG_CIFS_WEAK_PW_HASH
408 /* LANMAN and plaintext are less secure and off by default.
409 So we make this explicitly be turned on in kconfig (in the
410 build) and turned on at runtime (changed from the default)
411 in proc/fs/cifs or via mount parm. Unfortunately this is
412 needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
415 wct = 10; /* lanman 2 style sessionsetup */
416 } else if ((type == NTLM) || (type == NTLMv2)) {
417 /* For NTLMv2 failures eventually may need to retry NTLM */
418 wct = 13; /* old style NTLM sessionsetup */
419 } else /* same size: negotiate or auth, NTLMSSP or extended security */
422 rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
427 pSMB = (SESSION_SETUP_ANDX *)smb_buf;
429 capabilities = cifs_ssetup_hdr(ses, pSMB);
431 /* we will send the SMB in three pieces:
432 a fixed length beginning part, an optional
433 SPNEGO blob (which can be zero length), and a
434 last part which will include the strings
435 and rest of bcc area. This allows us to avoid
436 a large buffer 17K allocation */
437 iov[0].iov_base = (char *)pSMB;
438 iov[0].iov_len = smb_buf->smb_buf_length + 4;
440 /* setting this here allows the code at the end of the function
441 to free the request buffer if there's an error */
442 resp_buf_type = CIFS_SMALL_BUFFER;
444 /* 2000 big enough to fit max user, domain, NOS name etc. */
445 str_area = kmalloc(2000, GFP_KERNEL);
446 if (str_area == NULL) {
452 ses->flags &= ~CIFS_SES_LANMAN;
454 iov[1].iov_base = NULL;
457 if (type == LANMAN) {
458 #ifdef CONFIG_CIFS_WEAK_PW_HASH
459 char lnm_session_key[CIFS_SESS_KEY_SIZE];
461 pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
463 /* no capabilities flags in old lanman negotiation */
465 pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_SESS_KEY_SIZE);
466 /* BB calculate hash with password */
467 /* and copy into bcc */
469 calc_lanman_hash(ses->password, ses->server->cryptKey,
470 ses->server->secMode & SECMODE_PW_ENCRYPT ?
471 true : false, lnm_session_key);
473 ses->flags |= CIFS_SES_LANMAN;
474 memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_SESS_KEY_SIZE);
475 bcc_ptr += CIFS_SESS_KEY_SIZE;
477 /* can not sign if LANMAN negotiated so no need
478 to calculate signing key? but what if server
479 changed to do higher than lanman dialect and
480 we reconnected would we ever calc signing_key? */
482 cFYI(1, ("Negotiating LANMAN setting up strings"));
483 /* Unicode not allowed for LANMAN dialects */
484 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
486 } else if (type == NTLM) {
487 char ntlm_session_key[CIFS_SESS_KEY_SIZE];
489 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
490 pSMB->req_no_secext.CaseInsensitivePasswordLength =
491 cpu_to_le16(CIFS_SESS_KEY_SIZE);
492 pSMB->req_no_secext.CaseSensitivePasswordLength =
493 cpu_to_le16(CIFS_SESS_KEY_SIZE);
495 /* calculate session key */
496 SMBNTencrypt(ses->password, ses->server->cryptKey,
499 if (first_time) /* should this be moved into common code
500 with similar ntlmv2 path? */
501 cifs_calculate_mac_key(&ses->server->mac_signing_key,
502 ntlm_session_key, ses->password);
503 /* copy session key */
505 memcpy(bcc_ptr, (char *)ntlm_session_key, CIFS_SESS_KEY_SIZE);
506 bcc_ptr += CIFS_SESS_KEY_SIZE;
507 memcpy(bcc_ptr, (char *)ntlm_session_key, CIFS_SESS_KEY_SIZE);
508 bcc_ptr += CIFS_SESS_KEY_SIZE;
509 if (ses->capabilities & CAP_UNICODE) {
510 /* unicode strings must be word aligned */
511 if (iov[0].iov_len % 2) {
515 unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
517 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
518 } else if (type == NTLMv2) {
520 kmalloc(sizeof(struct ntlmv2_resp), GFP_KERNEL);
522 /* BB FIXME change all users of v2_sess_key to
523 struct ntlmv2_resp */
525 if (v2_sess_key == NULL) {
530 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
532 /* LM2 password would be here if we supported it */
533 pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
534 /* cpu_to_le16(LM2_SESS_KEY_SIZE); */
536 pSMB->req_no_secext.CaseSensitivePasswordLength =
537 cpu_to_le16(sizeof(struct ntlmv2_resp));
539 /* calculate session key */
540 setup_ntlmv2_rsp(ses, v2_sess_key, nls_cp);
541 if (first_time) /* should this be moved into common code
542 with similar ntlmv2 path? */
543 /* cifs_calculate_ntlmv2_mac_key(ses->server->mac_signing_key,
544 response BB FIXME, v2_sess_key); */
546 /* copy session key */
548 /* memcpy(bcc_ptr, (char *)ntlm_session_key,LM2_SESS_KEY_SIZE);
549 bcc_ptr += LM2_SESS_KEY_SIZE; */
550 memcpy(bcc_ptr, (char *)v2_sess_key,
551 sizeof(struct ntlmv2_resp));
552 bcc_ptr += sizeof(struct ntlmv2_resp);
554 if (ses->capabilities & CAP_UNICODE) {
555 if (iov[0].iov_len % 2) {
559 unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
561 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
562 } else if (type == Kerberos || type == MSKerberos) {
563 #ifdef CONFIG_CIFS_UPCALL
564 struct cifs_spnego_msg *msg;
565 spnego_key = cifs_get_spnego_key(ses);
566 if (IS_ERR(spnego_key)) {
567 rc = PTR_ERR(spnego_key);
572 msg = spnego_key->payload.data;
573 /* check version field to make sure that cifs.upcall is
574 sending us a response in an expected form */
575 if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
576 cERROR(1, ("incorrect version of cifs.upcall (expected"
578 CIFS_SPNEGO_UPCALL_VERSION, msg->version));
582 /* bail out if key is too long */
583 if (msg->sesskey_len >
584 sizeof(ses->server->mac_signing_key.data.krb5)) {
585 cERROR(1, ("Kerberos signing key too long (%u bytes)",
591 ses->server->mac_signing_key.len = msg->sesskey_len;
592 memcpy(ses->server->mac_signing_key.data.krb5,
593 msg->data, msg->sesskey_len);
595 pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
596 capabilities |= CAP_EXTENDED_SECURITY;
597 pSMB->req.Capabilities = cpu_to_le32(capabilities);
598 iov[1].iov_base = msg->data + msg->sesskey_len;
599 iov[1].iov_len = msg->secblob_len;
600 pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
602 if (ses->capabilities & CAP_UNICODE) {
603 /* unicode strings must be word aligned */
604 if ((iov[0].iov_len + iov[1].iov_len) % 2) {
608 unicode_oslm_strings(&bcc_ptr, nls_cp);
609 unicode_domain_string(&bcc_ptr, ses, nls_cp);
611 /* BB: is this right? */
612 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
613 #else /* ! CONFIG_CIFS_UPCALL */
614 cERROR(1, ("Kerberos negotiated but upcall support disabled!"));
617 #endif /* CONFIG_CIFS_UPCALL */
619 cERROR(1, ("secType %d not supported!", type));
624 iov[2].iov_base = str_area;
625 iov[2].iov_len = (long) bcc_ptr - (long) str_area;
627 count = iov[1].iov_len + iov[2].iov_len;
628 smb_buf->smb_buf_length += count;
630 BCC_LE(smb_buf) = cpu_to_le16(count);
632 rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
633 CIFS_STD_OP /* not long */ | CIFS_LOG_ERROR);
634 /* SMB request buf freed in SendReceive2 */
636 cFYI(1, ("ssetup rc from sendrecv2 is %d", rc));
640 pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
641 smb_buf = (struct smb_hdr *)iov[0].iov_base;
643 if ((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
645 cERROR(1, ("bad word count %d", smb_buf->WordCount));
648 action = le16_to_cpu(pSMB->resp.Action);
649 if (action & GUEST_LOGIN)
650 cFYI(1, ("Guest login")); /* BB mark SesInfo struct? */
651 ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
652 cFYI(1, ("UID = %d ", ses->Suid));
653 /* response can have either 3 or 4 word count - Samba sends 3 */
654 /* and lanman response is 3 */
655 bytes_remaining = BCC(smb_buf);
656 bcc_ptr = pByteArea(smb_buf);
658 if (smb_buf->WordCount == 4) {
660 blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
662 if (blob_len > bytes_remaining) {
663 cERROR(1, ("bad security blob length %d", blob_len));
667 bytes_remaining -= blob_len;
670 /* BB check if Unicode and decode strings */
671 if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
672 /* unicode string area must be word-aligned */
673 if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
677 decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
679 rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining,
685 key_revoke(spnego_key);
689 if (resp_buf_type == CIFS_SMALL_BUFFER) {
690 cFYI(1, ("ssetup freeing small buf %p", iov[0].iov_base));
691 cifs_small_buf_release(iov[0].iov_base);
692 } else if (resp_buf_type == CIFS_LARGE_BUFFER)
693 cifs_buf_release(iov[0].iov_base);