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;
290 cFYI(1, ("bleft %d", bleft));
293 /* SMB header is unaligned, so cifs servers word align start of
296 bleft--; /* Windows servers do not always double null terminate
297 their final Unicode string - in which case we
298 now will not attempt to decode the byte of junk
301 words_left = bleft / 2;
303 /* save off server operating system */
304 len = UniStrnlen((wchar_t *) data, words_left);
306 /* We look for obvious messed up bcc or strings in response so we do not go off
307 the end since (at least) WIN2K and Windows XP have a major bug in not null
308 terminating last Unicode string in response */
309 if (len >= words_left)
312 kfree(ses->serverOS);
313 /* UTF-8 string will not grow more than four times as big as UCS-16 */
314 ses->serverOS = kzalloc((4 * len) + 2 /* trailing null */, GFP_KERNEL);
315 if (ses->serverOS != NULL)
316 cifs_strfromUCS_le(ses->serverOS, (__le16 *)data, len, nls_cp);
317 data += 2 * (len + 1);
318 words_left -= len + 1;
320 /* save off server network operating system */
321 len = UniStrnlen((wchar_t *) data, words_left);
323 if (len >= words_left)
326 kfree(ses->serverNOS);
327 ses->serverNOS = kzalloc((4 * len) + 2 /* trailing null */, GFP_KERNEL);
328 if (ses->serverNOS != NULL) {
329 cifs_strfromUCS_le(ses->serverNOS, (__le16 *)data, len,
331 if (strncmp(ses->serverNOS, "NT LAN Manager 4", 16) == 0) {
332 cFYI(1, ("NT4 server"));
333 ses->flags |= CIFS_SES_NT4;
336 data += 2 * (len + 1);
337 words_left -= len + 1;
339 /* save off server domain */
340 len = UniStrnlen((wchar_t *) data, words_left);
342 if (len > words_left)
345 kfree(ses->serverDomain);
346 ses->serverDomain = kzalloc(2 * (len + 1), GFP_KERNEL); /* BB FIXME wrong length */
347 if (ses->serverDomain != NULL) {
348 cifs_strfromUCS_le(ses->serverDomain, (__le16 *)data, len,
350 ses->serverDomain[2*len] = 0;
351 ses->serverDomain[(2*len) + 1] = 0;
353 data += 2 * (len + 1);
354 words_left -= len + 1;
356 cFYI(1, ("words left: %d", words_left));
361 static int decode_ascii_ssetup(char **pbcc_area, int bleft,
362 struct cifsSesInfo *ses,
363 const struct nls_table *nls_cp)
367 char *bcc_ptr = *pbcc_area;
369 cFYI(1, ("decode sessetup ascii. bleft %d", bleft));
371 len = strnlen(bcc_ptr, bleft);
375 kfree(ses->serverOS);
377 ses->serverOS = kzalloc(len + 1, GFP_KERNEL);
379 strncpy(ses->serverOS, bcc_ptr, len);
380 if (strncmp(ses->serverOS, "OS/2", 4) == 0) {
381 cFYI(1, ("OS/2 server"));
382 ses->flags |= CIFS_SES_OS2;
388 len = strnlen(bcc_ptr, bleft);
392 kfree(ses->serverNOS);
394 ses->serverNOS = kzalloc(len + 1, GFP_KERNEL);
396 strncpy(ses->serverNOS, bcc_ptr, len);
401 len = strnlen(bcc_ptr, bleft);
405 /* No domain field in LANMAN case. Domain is
406 returned by old servers in the SMB negprot response */
407 /* BB For newer servers which do not support Unicode,
408 but thus do return domain here we could add parsing
409 for it later, but it is not very important */
410 cFYI(1, ("ascii: bytes left %d", bleft));
416 CIFS_SessSetup(unsigned int xid, struct cifsSesInfo *ses, int first_time,
417 const struct nls_table *nls_cp)
421 struct smb_hdr *smb_buf;
424 SESSION_SETUP_ANDX *pSMB;
429 enum securityEnum type;
432 struct key *spnego_key = NULL;
437 type = ses->server->secType;
439 cFYI(1, ("sess setup type %d", type));
440 if (type == LANMAN) {
441 #ifndef CONFIG_CIFS_WEAK_PW_HASH
442 /* LANMAN and plaintext are less secure and off by default.
443 So we make this explicitly be turned on in kconfig (in the
444 build) and turned on at runtime (changed from the default)
445 in proc/fs/cifs or via mount parm. Unfortunately this is
446 needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
449 wct = 10; /* lanman 2 style sessionsetup */
450 } else if ((type == NTLM) || (type == NTLMv2)) {
451 /* For NTLMv2 failures eventually may need to retry NTLM */
452 wct = 13; /* old style NTLM sessionsetup */
453 } else /* same size: negotiate or auth, NTLMSSP or extended security */
456 rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
461 pSMB = (SESSION_SETUP_ANDX *)smb_buf;
463 capabilities = cifs_ssetup_hdr(ses, pSMB);
465 /* we will send the SMB in three pieces:
466 a fixed length beginning part, an optional
467 SPNEGO blob (which can be zero length), and a
468 last part which will include the strings
469 and rest of bcc area. This allows us to avoid
470 a large buffer 17K allocation */
471 iov[0].iov_base = (char *)pSMB;
472 iov[0].iov_len = smb_buf->smb_buf_length + 4;
474 /* setting this here allows the code at the end of the function
475 to free the request buffer if there's an error */
476 resp_buf_type = CIFS_SMALL_BUFFER;
478 /* 2000 big enough to fit max user, domain, NOS name etc. */
479 str_area = kmalloc(2000, GFP_KERNEL);
480 if (str_area == NULL) {
486 ses->flags &= ~CIFS_SES_LANMAN;
488 iov[1].iov_base = NULL;
491 if (type == LANMAN) {
492 #ifdef CONFIG_CIFS_WEAK_PW_HASH
493 char lnm_session_key[CIFS_SESS_KEY_SIZE];
495 pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
497 /* no capabilities flags in old lanman negotiation */
499 pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_SESS_KEY_SIZE);
500 /* BB calculate hash with password */
501 /* and copy into bcc */
503 calc_lanman_hash(ses->password, ses->server->cryptKey,
504 ses->server->secMode & SECMODE_PW_ENCRYPT ?
505 true : false, lnm_session_key);
507 ses->flags |= CIFS_SES_LANMAN;
508 memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_SESS_KEY_SIZE);
509 bcc_ptr += CIFS_SESS_KEY_SIZE;
511 /* can not sign if LANMAN negotiated so no need
512 to calculate signing key? but what if server
513 changed to do higher than lanman dialect and
514 we reconnected would we ever calc signing_key? */
516 cFYI(1, ("Negotiating LANMAN setting up strings"));
517 /* Unicode not allowed for LANMAN dialects */
518 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
520 } else if (type == NTLM) {
521 char ntlm_session_key[CIFS_SESS_KEY_SIZE];
523 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
524 pSMB->req_no_secext.CaseInsensitivePasswordLength =
525 cpu_to_le16(CIFS_SESS_KEY_SIZE);
526 pSMB->req_no_secext.CaseSensitivePasswordLength =
527 cpu_to_le16(CIFS_SESS_KEY_SIZE);
529 /* calculate session key */
530 SMBNTencrypt(ses->password, ses->server->cryptKey,
533 if (first_time) /* should this be moved into common code
534 with similar ntlmv2 path? */
535 cifs_calculate_mac_key(&ses->server->mac_signing_key,
536 ntlm_session_key, ses->password);
537 /* copy session key */
539 memcpy(bcc_ptr, (char *)ntlm_session_key, CIFS_SESS_KEY_SIZE);
540 bcc_ptr += CIFS_SESS_KEY_SIZE;
541 memcpy(bcc_ptr, (char *)ntlm_session_key, CIFS_SESS_KEY_SIZE);
542 bcc_ptr += CIFS_SESS_KEY_SIZE;
543 if (ses->capabilities & CAP_UNICODE) {
544 /* unicode strings must be word aligned */
545 if (iov[0].iov_len % 2) {
549 unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
551 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
552 } else if (type == NTLMv2) {
554 kmalloc(sizeof(struct ntlmv2_resp), GFP_KERNEL);
556 /* BB FIXME change all users of v2_sess_key to
557 struct ntlmv2_resp */
559 if (v2_sess_key == NULL) {
564 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
566 /* LM2 password would be here if we supported it */
567 pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
568 /* cpu_to_le16(LM2_SESS_KEY_SIZE); */
570 pSMB->req_no_secext.CaseSensitivePasswordLength =
571 cpu_to_le16(sizeof(struct ntlmv2_resp));
573 /* calculate session key */
574 setup_ntlmv2_rsp(ses, v2_sess_key, nls_cp);
575 if (first_time) /* should this be moved into common code
576 with similar ntlmv2 path? */
577 /* cifs_calculate_ntlmv2_mac_key(ses->server->mac_signing_key,
578 response BB FIXME, v2_sess_key); */
580 /* copy session key */
582 /* memcpy(bcc_ptr, (char *)ntlm_session_key,LM2_SESS_KEY_SIZE);
583 bcc_ptr += LM2_SESS_KEY_SIZE; */
584 memcpy(bcc_ptr, (char *)v2_sess_key,
585 sizeof(struct ntlmv2_resp));
586 bcc_ptr += sizeof(struct ntlmv2_resp);
588 if (ses->capabilities & CAP_UNICODE) {
589 if (iov[0].iov_len % 2) {
593 unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
595 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
596 } else if (type == Kerberos || type == MSKerberos) {
597 #ifdef CONFIG_CIFS_UPCALL
598 struct cifs_spnego_msg *msg;
599 spnego_key = cifs_get_spnego_key(ses);
600 if (IS_ERR(spnego_key)) {
601 rc = PTR_ERR(spnego_key);
606 msg = spnego_key->payload.data;
607 /* check version field to make sure that cifs.upcall is
608 sending us a response in an expected form */
609 if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
610 cERROR(1, ("incorrect version of cifs.upcall (expected"
612 CIFS_SPNEGO_UPCALL_VERSION, msg->version));
616 /* bail out if key is too long */
617 if (msg->sesskey_len >
618 sizeof(ses->server->mac_signing_key.data.krb5)) {
619 cERROR(1, ("Kerberos signing key too long (%u bytes)",
625 ses->server->mac_signing_key.len = msg->sesskey_len;
626 memcpy(ses->server->mac_signing_key.data.krb5,
627 msg->data, msg->sesskey_len);
629 pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
630 capabilities |= CAP_EXTENDED_SECURITY;
631 pSMB->req.Capabilities = cpu_to_le32(capabilities);
632 iov[1].iov_base = msg->data + msg->sesskey_len;
633 iov[1].iov_len = msg->secblob_len;
634 pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
636 if (ses->capabilities & CAP_UNICODE) {
637 /* unicode strings must be word aligned */
638 if ((iov[0].iov_len + iov[1].iov_len) % 2) {
642 unicode_oslm_strings(&bcc_ptr, nls_cp);
643 unicode_domain_string(&bcc_ptr, ses, nls_cp);
645 /* BB: is this right? */
646 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
647 #else /* ! CONFIG_CIFS_UPCALL */
648 cERROR(1, ("Kerberos negotiated but upcall support disabled!"));
651 #endif /* CONFIG_CIFS_UPCALL */
653 cERROR(1, ("secType %d not supported!", type));
658 iov[2].iov_base = str_area;
659 iov[2].iov_len = (long) bcc_ptr - (long) str_area;
661 count = iov[1].iov_len + iov[2].iov_len;
662 smb_buf->smb_buf_length += count;
664 BCC_LE(smb_buf) = cpu_to_le16(count);
666 rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
667 CIFS_STD_OP /* not long */ | CIFS_LOG_ERROR);
668 /* SMB request buf freed in SendReceive2 */
670 cFYI(1, ("ssetup rc from sendrecv2 is %d", rc));
674 pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
675 smb_buf = (struct smb_hdr *)iov[0].iov_base;
677 if ((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
679 cERROR(1, ("bad word count %d", smb_buf->WordCount));
682 action = le16_to_cpu(pSMB->resp.Action);
683 if (action & GUEST_LOGIN)
684 cFYI(1, ("Guest login")); /* BB mark SesInfo struct? */
685 ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
686 cFYI(1, ("UID = %d ", ses->Suid));
687 /* response can have either 3 or 4 word count - Samba sends 3 */
688 /* and lanman response is 3 */
689 bytes_remaining = BCC(smb_buf);
690 bcc_ptr = pByteArea(smb_buf);
692 if (smb_buf->WordCount == 4) {
694 blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
696 if (blob_len > bytes_remaining) {
697 cERROR(1, ("bad security blob length %d", blob_len));
701 bytes_remaining -= blob_len;
704 /* BB check if Unicode and decode strings */
705 if (smb_buf->Flags2 & SMBFLG2_UNICODE)
706 rc = decode_unicode_ssetup(&bcc_ptr, bytes_remaining,
709 rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining,
714 key_revoke(spnego_key);
718 if (resp_buf_type == CIFS_SMALL_BUFFER) {
719 cFYI(1, ("ssetup freeing small buf %p", iov[0].iov_base));
720 cifs_small_buf_release(iov[0].iov_base);
721 } else if (resp_buf_type == CIFS_LARGE_BUFFER)
722 cifs_buf_release(iov[0].iov_base);