4 * SMB/CIFS session setup handling routines
6 * Copyright (c) International Business Machines Corp., 2006, 2007
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 le16_to_cpu(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;
280 static int decode_unicode_ssetup(char **pbcc_area, int bleft,
281 struct cifsSesInfo *ses,
282 const struct nls_table *nls_cp)
286 char *data = *pbcc_area;
288 cFYI(1, ("bleft %d", bleft));
291 * Windows servers do not always double null terminate their final
292 * Unicode string. Check to see if there are an uneven number of bytes
293 * left. If so, then add an extra NULL pad byte to the end of the
296 * See section 2.7.2 in "Implementing CIFS" for details
303 words_left = bleft / 2;
305 /* save off server operating system */
306 len = UniStrnlen((wchar_t *) data, words_left);
308 if (len >= words_left)
311 kfree(ses->serverOS);
312 /* UTF-8 string will not grow more than four times as big as UCS-16 */
313 ses->serverOS = kzalloc((4 * len) + 2 /* trailing null */, GFP_KERNEL);
314 if (ses->serverOS != NULL) {
315 cifs_strfromUCS_le(ses->serverOS, (__le16 *)data, len, nls_cp);
316 cFYI(1, ("serverOS=%s", ses->serverOS));
318 data += 2 * (len + 1);
319 words_left -= len + 1;
321 /* save off server network operating system */
322 len = UniStrnlen((wchar_t *) data, words_left);
324 if (len >= words_left)
327 kfree(ses->serverNOS);
328 ses->serverNOS = kzalloc((4 * len) + 2 /* trailing null */, GFP_KERNEL);
329 if (ses->serverNOS != NULL) {
330 cifs_strfromUCS_le(ses->serverNOS, (__le16 *)data, len,
332 cFYI(1, ("serverNOS=%s", ses->serverNOS));
333 if (strncmp(ses->serverNOS, "NT LAN Manager 4", 16) == 0) {
334 cFYI(1, ("NT4 server"));
335 ses->flags |= CIFS_SES_NT4;
338 data += 2 * (len + 1);
339 words_left -= len + 1;
341 /* save off server domain */
342 len = UniStrnlen((wchar_t *) data, words_left);
344 if (len > words_left)
347 kfree(ses->serverDomain);
348 ses->serverDomain = kzalloc((4 * len) + 2, GFP_KERNEL);
349 if (ses->serverDomain != NULL) {
350 cifs_strfromUCS_le(ses->serverDomain, (__le16 *)data, len,
352 cFYI(1, ("serverDomain=%s", ses->serverDomain));
354 data += 2 * (len + 1);
355 words_left -= len + 1;
357 cFYI(1, ("words left: %d", words_left));
362 static int decode_ascii_ssetup(char **pbcc_area, int bleft,
363 struct cifsSesInfo *ses,
364 const struct nls_table *nls_cp)
368 char *bcc_ptr = *pbcc_area;
370 cFYI(1, ("decode sessetup ascii. bleft %d", bleft));
372 len = strnlen(bcc_ptr, bleft);
376 kfree(ses->serverOS);
378 ses->serverOS = kzalloc(len + 1, GFP_KERNEL);
380 strncpy(ses->serverOS, bcc_ptr, len);
381 if (strncmp(ses->serverOS, "OS/2", 4) == 0) {
382 cFYI(1, ("OS/2 server"));
383 ses->flags |= CIFS_SES_OS2;
389 len = strnlen(bcc_ptr, bleft);
393 kfree(ses->serverNOS);
395 ses->serverNOS = kzalloc(len + 1, GFP_KERNEL);
397 strncpy(ses->serverNOS, bcc_ptr, len);
402 len = strnlen(bcc_ptr, bleft);
406 /* No domain field in LANMAN case. Domain is
407 returned by old servers in the SMB negprot response */
408 /* BB For newer servers which do not support Unicode,
409 but thus do return domain here we could add parsing
410 for it later, but it is not very important */
411 cFYI(1, ("ascii: bytes left %d", bleft));
417 CIFS_SessSetup(unsigned int xid, struct cifsSesInfo *ses, int first_time,
418 const struct nls_table *nls_cp)
422 struct smb_hdr *smb_buf;
425 SESSION_SETUP_ANDX *pSMB;
430 enum securityEnum type;
433 struct key *spnego_key = NULL;
438 type = ses->server->secType;
440 cFYI(1, ("sess setup type %d", type));
441 if (type == LANMAN) {
442 #ifndef CONFIG_CIFS_WEAK_PW_HASH
443 /* LANMAN and plaintext are less secure and off by default.
444 So we make this explicitly be turned on in kconfig (in the
445 build) and turned on at runtime (changed from the default)
446 in proc/fs/cifs or via mount parm. Unfortunately this is
447 needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
450 wct = 10; /* lanman 2 style sessionsetup */
451 } else if ((type == NTLM) || (type == NTLMv2)) {
452 /* For NTLMv2 failures eventually may need to retry NTLM */
453 wct = 13; /* old style NTLM sessionsetup */
454 } else /* same size: negotiate or auth, NTLMSSP or extended security */
457 rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
462 pSMB = (SESSION_SETUP_ANDX *)smb_buf;
464 capabilities = cifs_ssetup_hdr(ses, pSMB);
466 /* we will send the SMB in three pieces:
467 a fixed length beginning part, an optional
468 SPNEGO blob (which can be zero length), and a
469 last part which will include the strings
470 and rest of bcc area. This allows us to avoid
471 a large buffer 17K allocation */
472 iov[0].iov_base = (char *)pSMB;
473 iov[0].iov_len = smb_buf->smb_buf_length + 4;
475 /* setting this here allows the code at the end of the function
476 to free the request buffer if there's an error */
477 resp_buf_type = CIFS_SMALL_BUFFER;
479 /* 2000 big enough to fit max user, domain, NOS name etc. */
480 str_area = kmalloc(2000, GFP_KERNEL);
481 if (str_area == NULL) {
487 ses->flags &= ~CIFS_SES_LANMAN;
489 iov[1].iov_base = NULL;
492 if (type == LANMAN) {
493 #ifdef CONFIG_CIFS_WEAK_PW_HASH
494 char lnm_session_key[CIFS_SESS_KEY_SIZE];
496 pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
498 /* no capabilities flags in old lanman negotiation */
500 pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_SESS_KEY_SIZE);
501 /* BB calculate hash with password */
502 /* and copy into bcc */
504 calc_lanman_hash(ses->password, ses->server->cryptKey,
505 ses->server->secMode & SECMODE_PW_ENCRYPT ?
506 true : false, lnm_session_key);
508 ses->flags |= CIFS_SES_LANMAN;
509 memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_SESS_KEY_SIZE);
510 bcc_ptr += CIFS_SESS_KEY_SIZE;
512 /* can not sign if LANMAN negotiated so no need
513 to calculate signing key? but what if server
514 changed to do higher than lanman dialect and
515 we reconnected would we ever calc signing_key? */
517 cFYI(1, ("Negotiating LANMAN setting up strings"));
518 /* Unicode not allowed for LANMAN dialects */
519 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
521 } else if (type == NTLM) {
522 char ntlm_session_key[CIFS_SESS_KEY_SIZE];
524 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
525 pSMB->req_no_secext.CaseInsensitivePasswordLength =
526 cpu_to_le16(CIFS_SESS_KEY_SIZE);
527 pSMB->req_no_secext.CaseSensitivePasswordLength =
528 cpu_to_le16(CIFS_SESS_KEY_SIZE);
530 /* calculate session key */
531 SMBNTencrypt(ses->password, ses->server->cryptKey,
534 if (first_time) /* should this be moved into common code
535 with similar ntlmv2 path? */
536 cifs_calculate_mac_key(&ses->server->mac_signing_key,
537 ntlm_session_key, ses->password);
538 /* copy session key */
540 memcpy(bcc_ptr, (char *)ntlm_session_key, CIFS_SESS_KEY_SIZE);
541 bcc_ptr += CIFS_SESS_KEY_SIZE;
542 memcpy(bcc_ptr, (char *)ntlm_session_key, CIFS_SESS_KEY_SIZE);
543 bcc_ptr += CIFS_SESS_KEY_SIZE;
544 if (ses->capabilities & CAP_UNICODE) {
545 /* unicode strings must be word aligned */
546 if (iov[0].iov_len % 2) {
550 unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
552 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
553 } else if (type == NTLMv2) {
555 kmalloc(sizeof(struct ntlmv2_resp), GFP_KERNEL);
557 /* BB FIXME change all users of v2_sess_key to
558 struct ntlmv2_resp */
560 if (v2_sess_key == NULL) {
565 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
567 /* LM2 password would be here if we supported it */
568 pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
569 /* cpu_to_le16(LM2_SESS_KEY_SIZE); */
571 pSMB->req_no_secext.CaseSensitivePasswordLength =
572 cpu_to_le16(sizeof(struct ntlmv2_resp));
574 /* calculate session key */
575 setup_ntlmv2_rsp(ses, v2_sess_key, nls_cp);
576 if (first_time) /* should this be moved into common code
577 with similar ntlmv2 path? */
578 /* cifs_calculate_ntlmv2_mac_key(ses->server->mac_signing_key,
579 response BB FIXME, v2_sess_key); */
581 /* copy session key */
583 /* memcpy(bcc_ptr, (char *)ntlm_session_key,LM2_SESS_KEY_SIZE);
584 bcc_ptr += LM2_SESS_KEY_SIZE; */
585 memcpy(bcc_ptr, (char *)v2_sess_key,
586 sizeof(struct ntlmv2_resp));
587 bcc_ptr += sizeof(struct ntlmv2_resp);
589 if (ses->capabilities & CAP_UNICODE) {
590 if (iov[0].iov_len % 2) {
594 unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
596 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
597 } else if (type == Kerberos || type == MSKerberos) {
598 #ifdef CONFIG_CIFS_UPCALL
599 struct cifs_spnego_msg *msg;
600 spnego_key = cifs_get_spnego_key(ses);
601 if (IS_ERR(spnego_key)) {
602 rc = PTR_ERR(spnego_key);
607 msg = spnego_key->payload.data;
608 /* check version field to make sure that cifs.upcall is
609 sending us a response in an expected form */
610 if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
611 cERROR(1, ("incorrect version of cifs.upcall (expected"
613 CIFS_SPNEGO_UPCALL_VERSION, msg->version));
617 /* bail out if key is too long */
618 if (msg->sesskey_len >
619 sizeof(ses->server->mac_signing_key.data.krb5)) {
620 cERROR(1, ("Kerberos signing key too long (%u bytes)",
626 ses->server->mac_signing_key.len = msg->sesskey_len;
627 memcpy(ses->server->mac_signing_key.data.krb5,
628 msg->data, msg->sesskey_len);
630 pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
631 capabilities |= CAP_EXTENDED_SECURITY;
632 pSMB->req.Capabilities = cpu_to_le32(capabilities);
633 iov[1].iov_base = msg->data + msg->sesskey_len;
634 iov[1].iov_len = msg->secblob_len;
635 pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
637 if (ses->capabilities & CAP_UNICODE) {
638 /* unicode strings must be word aligned */
639 if ((iov[0].iov_len + iov[1].iov_len) % 2) {
643 unicode_oslm_strings(&bcc_ptr, nls_cp);
644 unicode_domain_string(&bcc_ptr, ses, nls_cp);
646 /* BB: is this right? */
647 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
648 #else /* ! CONFIG_CIFS_UPCALL */
649 cERROR(1, ("Kerberos negotiated but upcall support disabled!"));
652 #endif /* CONFIG_CIFS_UPCALL */
654 cERROR(1, ("secType %d not supported!", type));
659 iov[2].iov_base = str_area;
660 iov[2].iov_len = (long) bcc_ptr - (long) str_area;
662 count = iov[1].iov_len + iov[2].iov_len;
663 smb_buf->smb_buf_length += count;
665 BCC_LE(smb_buf) = cpu_to_le16(count);
667 rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
668 CIFS_STD_OP /* not long */ | CIFS_LOG_ERROR);
669 /* SMB request buf freed in SendReceive2 */
671 cFYI(1, ("ssetup rc from sendrecv2 is %d", rc));
675 pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
676 smb_buf = (struct smb_hdr *)iov[0].iov_base;
678 if ((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
680 cERROR(1, ("bad word count %d", smb_buf->WordCount));
683 action = le16_to_cpu(pSMB->resp.Action);
684 if (action & GUEST_LOGIN)
685 cFYI(1, ("Guest login")); /* BB mark SesInfo struct? */
686 ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
687 cFYI(1, ("UID = %d ", ses->Suid));
688 /* response can have either 3 or 4 word count - Samba sends 3 */
689 /* and lanman response is 3 */
690 bytes_remaining = BCC(smb_buf);
691 bcc_ptr = pByteArea(smb_buf);
693 if (smb_buf->WordCount == 4) {
695 blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
697 if (blob_len > bytes_remaining) {
698 cERROR(1, ("bad security blob length %d", blob_len));
702 bytes_remaining -= blob_len;
705 /* BB check if Unicode and decode strings */
706 if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
707 /* unicode string area must be word-aligned */
708 if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
712 rc = decode_unicode_ssetup(&bcc_ptr, bytes_remaining,
715 rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining,
721 key_revoke(spnego_key);
725 if (resp_buf_type == CIFS_SMALL_BUFFER) {
726 cFYI(1, ("ssetup freeing small buf %p", iov[0].iov_base));
727 cifs_small_buf_release(iov[0].iov_base);
728 } else if (resp_buf_type == CIFS_LARGE_BUFFER)
729 cifs_buf_release(iov[0].iov_base);