sess.c 15.5 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
/*
 *   fs/cifs/sess.c
 *
 *   SMB/CIFS session setup handling routines
 *
 *   Copyright (c) International Business Machines  Corp., 2006
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "ntlmssp.h"
#include "nterr.h"
31
#include <linux/utsname.h>
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76

extern void SMBNTencrypt(unsigned char *passwd, unsigned char *c8,
                         unsigned char *p24);

static __u32 cifs_ssetup_hdr(struct cifsSesInfo *ses, SESSION_SETUP_ANDX *pSMB)
{
	__u32 capabilities = 0;

	/* init fields common to all four types of SessSetup */
	/* note that header is initialized to zero in header_assemble */
	pSMB->req.AndXCommand = 0xFF;
	pSMB->req.MaxBufferSize = cpu_to_le16(ses->server->maxBuf);
	pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);

	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */

	/* BB verify whether signing required on neg or just on auth frame 
	   (and NTLM case) */

	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;

	if(ses->server->secMode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;

	if (ses->capabilities & CAP_UNICODE) {
		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
		capabilities |= CAP_UNICODE;
	}
	if (ses->capabilities & CAP_STATUS32) {
		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
		capabilities |= CAP_STATUS32;
	}
	if (ses->capabilities & CAP_DFS) {
		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
		capabilities |= CAP_DFS;
	}
	if (ses->capabilities & CAP_UNIX) {
		capabilities |= CAP_UNIX;
	}

	/* BB check whether to init vcnum BB */
	return capabilities;
}

77
static void unicode_ssetup_strings(char ** pbcc_area, struct cifsSesInfo *ses,
78
79
80
81
82
83
84
85
			    const struct nls_table * nls_cp)
{
	char * bcc_ptr = *pbcc_area;
	int bytes_ret = 0;

	/* BB FIXME add check that strings total less
	than 335 or will need to send them as arrays */

86
87
	/* unicode strings, must be word aligned before the call */
/*	if ((long) bcc_ptr % 2)	{
88
89
		*bcc_ptr = 0;
		bcc_ptr++;
90
	} */
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
	/* copy user */
	if(ses->userName == NULL) {
		/* BB what about null user mounts - check that we do this BB */
	} else { /* 300 should be long enough for any conceivable user name */
		bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->userName,
					  300, nls_cp);
	}
	bcc_ptr += 2 * bytes_ret;
	bcc_ptr += 2; /* account for null termination */
	/* copy domain */
	if(ses->domainName == NULL)
		bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr,
					  "CIFS_LINUX_DOM", 32, nls_cp);
	else
		bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->domainName, 
					  256, nls_cp);
	bcc_ptr += 2 * bytes_ret;
	bcc_ptr += 2;  /* account for null terminator */

	/* Copy OS version */
	bytes_ret = cifs_strtoUCS((__le16 *)bcc_ptr, "Linux version ", 32,
				  nls_cp);
	bcc_ptr += 2 * bytes_ret;
	bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, system_utsname.release,
				  32, nls_cp);
	bcc_ptr += 2 * bytes_ret;
	bcc_ptr += 2; /* trailing null */

	bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
                                  32, nls_cp);
	bcc_ptr += 2 * bytes_ret;
	bcc_ptr += 2; /* trailing null */

	*pbcc_area = bcc_ptr;
}

127
static void ascii_ssetup_strings(char ** pbcc_area, struct cifsSesInfo *ses,
128
129
130
131
132
133
134
135
136
137
138
139
140
			  const struct nls_table * nls_cp)
{
	char * bcc_ptr = *pbcc_area;

	/* copy user */
	/* BB what about null user mounts - check that we do this BB */
        /* copy user */
        if(ses->userName == NULL) {
                /* BB what about null user mounts - check that we do this BB */
        } else { /* 300 should be long enough for any conceivable user name */
                strncpy(bcc_ptr, ses->userName, 300);
        }
	/* BB improve check for overflow */
141
        bcc_ptr += strnlen(ses->userName, 300);
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
	*bcc_ptr = 0;
        bcc_ptr++; /* account for null termination */

        /* copy domain */
	
        if(ses->domainName == NULL) {
                strcpy(bcc_ptr, "CIFS_LINUX_DOM");
		bcc_ptr += 14;  /* strlen(CIFS_LINUX_DOM) */
 	} else {
                strncpy(bcc_ptr, ses->domainName, 256); 
		bcc_ptr += strnlen(ses->domainName, 256);
	}
	*bcc_ptr = 0;
	bcc_ptr++;

	/* BB check for overflow here */

	strcpy(bcc_ptr, "Linux version ");
	bcc_ptr += strlen("Linux version ");
	strcpy(bcc_ptr, system_utsname.release);
	bcc_ptr += strlen(system_utsname.release) + 1;

	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;

        *pbcc_area = bcc_ptr;
}

170
static int decode_unicode_ssetup(char ** pbcc_area, int bleft, struct cifsSesInfo *ses,
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
                            const struct nls_table * nls_cp)
{
	int rc = 0;
	int words_left, len;
	char * data = *pbcc_area;



	cFYI(1,("bleft %d",bleft));


	/* word align, if bytes remaining is not even */
	if(bleft % 2) {
		bleft--;
		data++;
	}
	words_left = bleft / 2;

	/* save off server operating system */
	len = UniStrnlen((wchar_t *) data, words_left);

/* We look for obvious messed up bcc or strings in response so we do not go off
   the end since (at least) WIN2K and Windows XP have a major bug in not null
   terminating last Unicode string in response  */
	if(len >= words_left)
		return rc;

	if(ses->serverOS)
		kfree(ses->serverOS);
	/* UTF-8 string will not grow more than four times as big as UCS-16 */
	ses->serverOS = kzalloc(4 * len, GFP_KERNEL);
	if(ses->serverOS != NULL) {
		cifs_strfromUCS_le(ses->serverOS, (__le16 *)data, len,
				   nls_cp);
	}
	data += 2 * (len + 1);
	words_left -= len + 1;

	/* save off server network operating system */
	len = UniStrnlen((wchar_t *) data, words_left);

	if(len >= words_left)
		return rc;

	if(ses->serverNOS)
		kfree(ses->serverNOS);
	ses->serverNOS = kzalloc(4 * len, GFP_KERNEL); /* BB this is wrong length FIXME BB */
	if(ses->serverNOS != NULL) {
		cifs_strfromUCS_le(ses->serverNOS, (__le16 *)data, len,
				   nls_cp);
		if(strncmp(ses->serverNOS, "NT LAN Manager 4",16) == 0) {
			cFYI(1,("NT4 server"));
			ses->flags |= CIFS_SES_NT4;
		}
	}
	data += 2 * (len + 1);
	words_left -= len + 1;

        /* save off server domain */
        len = UniStrnlen((wchar_t *) data, words_left);

        if(len > words_left)
                return rc;

        if(ses->serverDomain)
                kfree(ses->serverDomain);
        ses->serverDomain = kzalloc(2 * (len + 1), GFP_KERNEL); /* BB FIXME wrong length */
        if(ses->serverDomain != NULL) {
                cifs_strfromUCS_le(ses->serverDomain, (__le16 *)data, len,
                                   nls_cp);
                ses->serverDomain[2*len] = 0;
                ses->serverDomain[(2*len) + 1] = 0;
        }
        data += 2 * (len + 1);
        words_left -= len + 1;
	
	cFYI(1,("words left: %d",words_left));

	return rc;
}

252
static int decode_ascii_ssetup(char ** pbcc_area, int bleft, struct cifsSesInfo *ses,
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
                            const struct nls_table * nls_cp)
{
	int rc = 0;
	int len;
	char * bcc_ptr = *pbcc_area;

	cFYI(1,("decode sessetup ascii. bleft %d", bleft));
	
	len = strnlen(bcc_ptr, bleft);
	if(len >= bleft)
		return rc;
	
	if(ses->serverOS)
		kfree(ses->serverOS);

	ses->serverOS = kzalloc(len + 1, GFP_KERNEL);
	if(ses->serverOS)
		strncpy(ses->serverOS, bcc_ptr, len);

	bcc_ptr += len + 1;
	bleft -= len + 1;

	len = strnlen(bcc_ptr, bleft);
	if(len >= bleft)
		return rc;

	if(ses->serverNOS)
		kfree(ses->serverNOS);

	ses->serverNOS = kzalloc(len + 1, GFP_KERNEL);
	if(ses->serverNOS)
		strncpy(ses->serverNOS, bcc_ptr, len);

	bcc_ptr += len + 1;
	bleft -= len + 1;

        len = strnlen(bcc_ptr, bleft);
        if(len > bleft)
                return rc;

        if(ses->serverDomain)
                kfree(ses->serverDomain);

        ses->serverDomain = kzalloc(len + 1, GFP_KERNEL);
        if(ses->serverOS)
                strncpy(ses->serverOS, bcc_ptr, len);

        bcc_ptr += len + 1;
	bleft -= len + 1;

	cFYI(1,("ascii: bytes left %d",bleft));

	return rc;
}

int 
CIFS_SessSetup(unsigned int xid, struct cifsSesInfo *ses, int first_time,
		const struct nls_table *nls_cp)
{
	int rc = 0;
	int wct;
	struct smb_hdr *smb_buf;
	char *bcc_ptr;
316
	char *str_area;
317
318
319
320
	SESSION_SETUP_ANDX *pSMB;
	__u32 capabilities;
	int count;
	int resp_buf_type = 0;
321
	struct kvec iov[2];
322
323
324
	enum securityEnum type;
	__u16 action;
	int bytes_remaining;
325
326

	cFYI(1,("new sess setup"));
327
328
329
330
331
332
333
334
335
336
337
338
339
340
	if(ses == NULL)
		return -EINVAL;

	type = ses->server->secType;
	if(type == LANMAN) {
#ifndef CONFIG_CIFS_WEAK_PW_HASH
		/* LANMAN and plaintext are less secure and off by default.
		So we make this explicitly be turned on in kconfig (in the
		build) and turned on at runtime (changed from the default)
		in proc/fs/cifs or via mount parm.  Unfortunately this is
		needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
		return -EOPNOTSUPP;
#endif
		wct = 10; /* lanman 2 style sessionsetup */
341
342
	} else if((type == NTLM) || (type == NTLMv2)) { 
		/* For NTLMv2 failures eventually may need to retry NTLM */
343
		wct = 13; /* old style NTLM sessionsetup */
344
	} else /* same size for negotiate or auth, NTLMSSP or extended security */
345
346
347
348
349
350
351
352
353
354
		wct = 12;

	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
			    (void **)&smb_buf);
	if(rc)
		return rc;

	pSMB = (SESSION_SETUP_ANDX *)smb_buf;

	capabilities = cifs_ssetup_hdr(ses, pSMB);
355
356
357
358
359
360
361
362
363
364
365
366

	/* we will send the SMB in two pieces,
	a fixed length beginning part, and a
	second part which will include the strings
	and rest of bcc area, in order to avoid having
	to do a large buffer 17K allocation */
        iov[0].iov_base = (char *)pSMB;
        iov[0].iov_len = smb_buf->smb_buf_length + 4;

	/* 2000 big enough to fit max user, domain, NOS name etc. */
	str_area = kmalloc(2000, GFP_KERNEL);
	bcc_ptr = str_area;
367
368
369

	if(type == LANMAN) {
#ifdef CONFIG_CIFS_WEAK_PW_HASH
370
		char lnm_session_key[CIFS_SESS_KEY_SIZE];
371
372
373

		/* no capabilities flags in old lanman negotiation */

374
		pSMB->old_req.PasswordLength = CIFS_SESS_KEY_SIZE; 
375
376
377
		/* BB calculate hash with password */
		/* and copy into bcc */

378
		calc_lanman_hash(ses, lnm_session_key);
379

380
/* #ifdef CONFIG_CIFS_DEBUG2
381
		cifs_dump_mem("cryptkey: ",ses->server->cryptKey,
382
			CIFS_SESS_KEY_SIZE);
383
#endif */
384
385
		memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_SESS_KEY_SIZE);
		bcc_ptr += CIFS_SESS_KEY_SIZE;
386
387
388
389
390
391

		/* can not sign if LANMAN negotiated so no need
		to calculate signing key? but what if server
		changed to do higher than lanman dialect and
		we reconnected would we ever calc signing_key? */

392
		cFYI(1,("Negotiating LANMAN setting up strings"));
393
394
395
396
		/* Unicode not allowed for LANMAN dialects */
		ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
#endif    
	} else if (type == NTLM) {
397
		char ntlm_session_key[CIFS_SESS_KEY_SIZE];
398
399
400

		pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
		pSMB->req_no_secext.CaseInsensitivePasswordLength =
401
			cpu_to_le16(CIFS_SESS_KEY_SIZE);
402
		pSMB->req_no_secext.CaseSensitivePasswordLength =
403
			cpu_to_le16(CIFS_SESS_KEY_SIZE);
404
405
406
407
408
409
410
	
		/* calculate session key */
		SMBNTencrypt(ses->password, ses->server->cryptKey,
			     ntlm_session_key);

		if(first_time) /* should this be moved into common code 
				  with similar ntlmv2 path? */
411
			cifs_calculate_mac_key(ses->server->mac_signing_key,
412
413
414
				ntlm_session_key, ses->password);
		/* copy session key */

415
416
417
418
		memcpy(bcc_ptr, (char *)ntlm_session_key,CIFS_SESS_KEY_SIZE);
		bcc_ptr += CIFS_SESS_KEY_SIZE;
		memcpy(bcc_ptr, (char *)ntlm_session_key,CIFS_SESS_KEY_SIZE);
		bcc_ptr += CIFS_SESS_KEY_SIZE;
419
420
421
422
423
424
		if(ses->capabilities & CAP_UNICODE) {
			/* unicode strings must be word aligned */
			if (iov[0].iov_len % 2) {
				*bcc_ptr = 0;
				bcc_ptr++;		
			}	
425
			unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
426
		} else
427
428
			ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
	} else if (type == NTLMv2) {
Steve French's avatar
Steve French committed
429
430
		char * v2_sess_key = 
			kmalloc(sizeof(struct ntlmv2_resp), GFP_KERNEL);
Steve French's avatar
Steve French committed
431
432
433

		/* BB FIXME change all users of v2_sess_key to
		   struct ntlmv2_resp */
434
435
436
437
438
439
440
441
442
443
444
445
446

		if(v2_sess_key == NULL) {
			cifs_small_buf_release(smb_buf);
			return -ENOMEM;
		}

		pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);

		/* LM2 password would be here if we supported it */
		pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
		/*	cpu_to_le16(LM2_SESS_KEY_SIZE); */

		pSMB->req_no_secext.CaseSensitivePasswordLength =
Steve French's avatar
Steve French committed
447
			cpu_to_le16(sizeof(struct ntlmv2_resp));
448
449

		/* calculate session key */
Steve French's avatar
Steve French committed
450
		setup_ntlmv2_rsp(ses, v2_sess_key, nls_cp);
451
452
453
454
455
456
457
458
459
		if(first_time) /* should this be moved into common code
			          with similar ntlmv2 path? */
		/*   cifs_calculate_ntlmv2_mac_key(ses->server->mac_signing_key,
				response BB FIXME, v2_sess_key); */

		/* copy session key */

	/*	memcpy(bcc_ptr, (char *)ntlm_session_key,LM2_SESS_KEY_SIZE);
		bcc_ptr += LM2_SESS_KEY_SIZE; */
Steve French's avatar
Steve French committed
460
461
462
		memcpy(bcc_ptr, (char *)v2_sess_key, sizeof(struct ntlmv2_resp));
		bcc_ptr += sizeof(struct ntlmv2_resp);
		kfree(v2_sess_key);
463
464
465
466
		if(ses->capabilities & CAP_UNICODE) {
			if(iov[0].iov_len % 2) {
				*bcc_ptr = 0;
			}	bcc_ptr++;
467
			unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
468
		} else
469
470
471
472
473
474
475
476
			ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
	} else /* NTLMSSP or SPNEGO */ {
		pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
		capabilities |= CAP_EXTENDED_SECURITY;
		pSMB->req.Capabilities = cpu_to_le32(capabilities);
		/* BB set password lengths */
	}

477
	count = (long) bcc_ptr - (long) str_area;
478
479
480
481
	smb_buf->smb_buf_length += count;

	BCC_LE(smb_buf) = cpu_to_le16(count);

482
483
484
	iov[1].iov_base = str_area;
	iov[1].iov_len = count; 
	rc = SendReceive2(xid, ses, iov, 2 /* num_iovecs */, &resp_buf_type, 0);
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
	/* SMB request buf freed in SendReceive2 */

	cFYI(1,("ssetup rc from sendrecv2 is %d",rc));
	if(rc)
		goto ssetup_exit;

	pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
	smb_buf = (struct smb_hdr *)iov[0].iov_base;

	if((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
		rc = -EIO;
		cERROR(1,("bad word count %d", smb_buf->WordCount));
		goto ssetup_exit;
	}
	action = le16_to_cpu(pSMB->resp.Action);
	if (action & GUEST_LOGIN)
501
		cFYI(1, ("Guest login")); /* BB mark SesInfo struct? */
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
	cFYI(1, ("UID = %d ", ses->Suid));
	/* response can have either 3 or 4 word count - Samba sends 3 */
	/* and lanman response is 3 */
	bytes_remaining = BCC(smb_buf);
	bcc_ptr = pByteArea(smb_buf);

	if(smb_buf->WordCount == 4) {
		__u16 blob_len;
		blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
		bcc_ptr += blob_len;
		if(blob_len > bytes_remaining) {
			cERROR(1,("bad security blob length %d", blob_len));
			rc = -EINVAL;
			goto ssetup_exit;
		}
		bytes_remaining -= blob_len;
	}	

	/* BB check if Unicode and decode strings */
	if(smb_buf->Flags2 & SMBFLG2_UNICODE)
		rc = decode_unicode_ssetup(&bcc_ptr, bytes_remaining,
						   ses, nls_cp);
	else
		rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,nls_cp);
	
ssetup_exit:
529
	kfree(str_area);
530
531
532
533
534
535
536
537
	if(resp_buf_type == CIFS_SMALL_BUFFER) {
		cFYI(1,("ssetup freeing small buf %p", iov[0].iov_base));
		cifs_small_buf_release(iov[0].iov_base);
	} else if(resp_buf_type == CIFS_LARGE_BUFFER)
		cifs_buf_release(iov[0].iov_base);

	return rc;
}