xref: /linux/fs/smb/client/smb1session.c (revision bf4afc53b77aeaa48b5409da5c8da6bb4eff7f43)
1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3  *
4  *   SMB/CIFS session setup handling routines
5  *
6  *   Copyright (c) International Business Machines  Corp., 2006, 2009
7  *   Author(s): Steve French (sfrench@us.ibm.com)
8  *
9  */
10 
11 #include "cifsproto.h"
12 #include "smb1proto.h"
13 #include "ntlmssp.h"
14 #include "nterr.h"
15 #include "cifs_spnego.h"
16 #include "cifs_unicode.h"
17 #include "cifs_debug.h"
18 
19 struct sess_data {
20 	unsigned int xid;
21 	struct cifs_ses *ses;
22 	struct TCP_Server_Info *server;
23 	struct nls_table *nls_cp;
24 	void (*func)(struct sess_data *);
25 	int result;
26 	unsigned int in_len;
27 
28 	/* we will send the SMB in three pieces:
29 	 * a fixed length beginning part, an optional
30 	 * SPNEGO blob (which can be zero length), and a
31 	 * last part which will include the strings
32 	 * and rest of bcc area. This allows us to avoid
33 	 * a large buffer 17K allocation
34 	 */
35 	int buf0_type;
36 	struct kvec iov[3];
37 };
38 
cifs_ssetup_hdr(struct cifs_ses * ses,struct TCP_Server_Info * server,SESSION_SETUP_ANDX * pSMB)39 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
40 			     struct TCP_Server_Info *server,
41 			     SESSION_SETUP_ANDX *pSMB)
42 {
43 	__u32 capabilities = 0;
44 
45 	/* init fields common to all four types of SessSetup */
46 	/* Note that offsets for first seven fields in req struct are same  */
47 	/*	in CIFS Specs so does not matter which of 3 forms of struct */
48 	/*	that we use in next few lines                               */
49 	/* Note that header is initialized to zero in header_assemble */
50 	pSMB->req.AndXCommand = 0xFF;
51 	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
52 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
53 					USHRT_MAX));
54 	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
55 	pSMB->req.VcNumber = cpu_to_le16(1);
56 	pSMB->req.SessionKey = server->session_key_id;
57 
58 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
59 
60 	/* BB verify whether signing required on neg or just auth frame (and NTLM case) */
61 
62 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
63 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
64 
65 	if (server->sign)
66 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
67 
68 	if (ses->capabilities & CAP_UNICODE) {
69 		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
70 		capabilities |= CAP_UNICODE;
71 	}
72 	if (ses->capabilities & CAP_STATUS32) {
73 		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
74 		capabilities |= CAP_STATUS32;
75 	}
76 	if (ses->capabilities & CAP_DFS) {
77 		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
78 		capabilities |= CAP_DFS;
79 	}
80 	if (ses->capabilities & CAP_UNIX)
81 		capabilities |= CAP_UNIX;
82 
83 	return capabilities;
84 }
85 
86 static void
unicode_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)87 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
88 {
89 	char *bcc_ptr = *pbcc_area;
90 	int bytes_ret = 0;
91 
92 	/* Copy OS version */
93 	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
94 				    nls_cp);
95 	bcc_ptr += 2 * bytes_ret;
96 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
97 				    32, nls_cp);
98 	bcc_ptr += 2 * bytes_ret;
99 	bcc_ptr += 2; /* trailing null */
100 
101 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
102 				    32, nls_cp);
103 	bcc_ptr += 2 * bytes_ret;
104 	bcc_ptr += 2; /* trailing null */
105 
106 	*pbcc_area = bcc_ptr;
107 }
108 
109 static void
ascii_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)110 ascii_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
111 {
112 	char *bcc_ptr = *pbcc_area;
113 
114 	strcpy(bcc_ptr, "Linux version ");
115 	bcc_ptr += strlen("Linux version ");
116 	strcpy(bcc_ptr, init_utsname()->release);
117 	bcc_ptr += strlen(init_utsname()->release) + 1;
118 
119 	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
120 	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
121 
122 	*pbcc_area = bcc_ptr;
123 }
124 
unicode_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)125 static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
126 				   const struct nls_table *nls_cp)
127 {
128 	char *bcc_ptr = *pbcc_area;
129 	int bytes_ret = 0;
130 
131 	/* copy domain */
132 	if (ses->domainName == NULL) {
133 		/*
134 		 * Sending null domain better than using a bogus domain name (as
135 		 * we did briefly in 2.6.18) since server will use its default
136 		 */
137 		*bcc_ptr = 0;
138 		*(bcc_ptr+1) = 0;
139 		bytes_ret = 0;
140 	} else
141 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
142 					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
143 	bcc_ptr += 2 * bytes_ret;
144 	bcc_ptr += 2;  /* account for null terminator */
145 
146 	*pbcc_area = bcc_ptr;
147 }
148 
ascii_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)149 static void ascii_domain_string(char **pbcc_area, struct cifs_ses *ses,
150 				const struct nls_table *nls_cp)
151 {
152 	char *bcc_ptr = *pbcc_area;
153 	int len;
154 
155 	/* copy domain */
156 	if (ses->domainName != NULL) {
157 		len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
158 		if (WARN_ON_ONCE(len < 0))
159 			len = CIFS_MAX_DOMAINNAME_LEN - 1;
160 		bcc_ptr += len;
161 	} /* else we send a null domain name so server will default to its own domain */
162 	*bcc_ptr = 0;
163 	bcc_ptr++;
164 
165 	*pbcc_area = bcc_ptr;
166 }
167 
unicode_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)168 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
169 				   const struct nls_table *nls_cp)
170 {
171 	char *bcc_ptr = *pbcc_area;
172 	int bytes_ret = 0;
173 
174 	/* BB FIXME add check that strings less than 335 or will need to send as arrays */
175 
176 	/* copy user */
177 	if (ses->user_name == NULL) {
178 		/* null user mount */
179 		*bcc_ptr = 0;
180 		*(bcc_ptr+1) = 0;
181 	} else {
182 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
183 					    CIFS_MAX_USERNAME_LEN, nls_cp);
184 	}
185 	bcc_ptr += 2 * bytes_ret;
186 	bcc_ptr += 2; /* account for null termination */
187 
188 	unicode_domain_string(&bcc_ptr, ses, nls_cp);
189 	unicode_oslm_strings(&bcc_ptr, nls_cp);
190 
191 	*pbcc_area = bcc_ptr;
192 }
193 
ascii_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)194 static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
195 				 const struct nls_table *nls_cp)
196 {
197 	char *bcc_ptr = *pbcc_area;
198 	int len;
199 
200 	/* copy user */
201 	/* BB what about null user mounts - check that we do this BB */
202 	/* copy user */
203 	if (ses->user_name != NULL) {
204 		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
205 		if (WARN_ON_ONCE(len < 0))
206 			len = CIFS_MAX_USERNAME_LEN - 1;
207 		bcc_ptr += len;
208 	}
209 	/* else null user mount */
210 	*bcc_ptr = 0;
211 	bcc_ptr++; /* account for null termination */
212 
213 	/* BB check for overflow here */
214 
215 	ascii_domain_string(&bcc_ptr, ses, nls_cp);
216 	ascii_oslm_strings(&bcc_ptr, nls_cp);
217 
218 	*pbcc_area = bcc_ptr;
219 }
220 
221 static void
decode_unicode_ssetup(char ** pbcc_area,int bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)222 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
223 		      const struct nls_table *nls_cp)
224 {
225 	int len;
226 	char *data = *pbcc_area;
227 
228 	cifs_dbg(FYI, "bleft %d\n", bleft);
229 
230 	kfree(ses->serverOS);
231 	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
232 	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
233 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
234 	data += len;
235 	bleft -= len;
236 	if (bleft <= 0)
237 		return;
238 
239 	kfree(ses->serverNOS);
240 	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
241 	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
242 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
243 	data += len;
244 	bleft -= len;
245 	if (bleft <= 0)
246 		return;
247 
248 	kfree(ses->serverDomain);
249 	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
250 	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
251 
252 	return;
253 }
254 
decode_ascii_ssetup(char ** pbcc_area,__u16 bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)255 static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
256 				struct cifs_ses *ses,
257 				const struct nls_table *nls_cp)
258 {
259 	int len;
260 	char *bcc_ptr = *pbcc_area;
261 
262 	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
263 
264 	len = strnlen(bcc_ptr, bleft);
265 	if (len >= bleft)
266 		return;
267 
268 	kfree(ses->serverOS);
269 
270 	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
271 	if (ses->serverOS) {
272 		memcpy(ses->serverOS, bcc_ptr, len);
273 		ses->serverOS[len] = 0;
274 		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
275 			cifs_dbg(FYI, "OS/2 server\n");
276 	}
277 
278 	bcc_ptr += len + 1;
279 	bleft -= len + 1;
280 
281 	len = strnlen(bcc_ptr, bleft);
282 	if (len >= bleft)
283 		return;
284 
285 	kfree(ses->serverNOS);
286 
287 	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
288 	if (ses->serverNOS) {
289 		memcpy(ses->serverNOS, bcc_ptr, len);
290 		ses->serverNOS[len] = 0;
291 	}
292 
293 	bcc_ptr += len + 1;
294 	bleft -= len + 1;
295 
296 	len = strnlen(bcc_ptr, bleft);
297 	if (len > bleft)
298 		return;
299 
300 	/*
301 	 * No domain field in LANMAN case. Domain is
302 	 * returned by old servers in the SMB negprot response
303 	 *
304 	 * BB For newer servers which do not support Unicode,
305 	 * but thus do return domain here, we could add parsing
306 	 * for it later, but it is not very important
307 	 */
308 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
309 }
310 
311 static int
sess_alloc_buffer(struct sess_data * sess_data,int wct)312 sess_alloc_buffer(struct sess_data *sess_data, int wct)
313 {
314 	int rc;
315 	struct cifs_ses *ses = sess_data->ses;
316 	struct smb_hdr *smb_buf;
317 
318 	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
319 				  (void **)&smb_buf);
320 
321 	if (rc < 0)
322 		return rc;
323 
324 	sess_data->in_len = rc;
325 	sess_data->iov[0].iov_base = (char *)smb_buf;
326 	sess_data->iov[0].iov_len = sess_data->in_len;
327 	/*
328 	 * This variable will be used to clear the buffer
329 	 * allocated above in case of any error in the calling function.
330 	 */
331 	sess_data->buf0_type = CIFS_SMALL_BUFFER;
332 
333 	/* 2000 big enough to fit max user, domain, NOS name etc. */
334 	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
335 	if (!sess_data->iov[2].iov_base) {
336 		rc = -ENOMEM;
337 		goto out_free_smb_buf;
338 	}
339 
340 	return 0;
341 
342 out_free_smb_buf:
343 	cifs_small_buf_release(smb_buf);
344 	sess_data->iov[0].iov_base = NULL;
345 	sess_data->iov[0].iov_len = 0;
346 	sess_data->buf0_type = CIFS_NO_BUFFER;
347 	return rc;
348 }
349 
350 static void
sess_free_buffer(struct sess_data * sess_data)351 sess_free_buffer(struct sess_data *sess_data)
352 {
353 	struct kvec *iov = sess_data->iov;
354 
355 	/*
356 	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
357 	 * Note that iov[1] is already freed by caller.
358 	 */
359 	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
360 		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
361 
362 	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
363 	sess_data->buf0_type = CIFS_NO_BUFFER;
364 	kfree_sensitive(iov[2].iov_base);
365 }
366 
367 static int
sess_establish_session(struct sess_data * sess_data)368 sess_establish_session(struct sess_data *sess_data)
369 {
370 	struct cifs_ses *ses = sess_data->ses;
371 	struct TCP_Server_Info *server = sess_data->server;
372 
373 	cifs_server_lock(server);
374 	if (!server->session_estab) {
375 		if (server->sign) {
376 			server->session_key.response =
377 				kmemdup(ses->auth_key.response,
378 				ses->auth_key.len, GFP_KERNEL);
379 			if (!server->session_key.response) {
380 				cifs_server_unlock(server);
381 				return -ENOMEM;
382 			}
383 			server->session_key.len =
384 						ses->auth_key.len;
385 		}
386 		server->sequence_number = 0x2;
387 		server->session_estab = true;
388 	}
389 	cifs_server_unlock(server);
390 
391 	cifs_dbg(FYI, "CIFS session established successfully\n");
392 	return 0;
393 }
394 
395 static int
sess_sendreceive(struct sess_data * sess_data)396 sess_sendreceive(struct sess_data *sess_data)
397 {
398 	int rc;
399 	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
400 	__u16 count;
401 	struct kvec rsp_iov = { NULL, 0 };
402 
403 	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
404 	sess_data->in_len += count;
405 	put_bcc(count, smb_buf);
406 
407 	rc = SendReceive2(sess_data->xid, sess_data->ses,
408 			  sess_data->iov, 3 /* num_iovecs */,
409 			  &sess_data->buf0_type,
410 			  CIFS_LOG_ERROR, &rsp_iov);
411 	cifs_small_buf_release(sess_data->iov[0].iov_base);
412 	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
413 
414 	return rc;
415 }
416 
417 static void
sess_auth_ntlmv2(struct sess_data * sess_data)418 sess_auth_ntlmv2(struct sess_data *sess_data)
419 {
420 	int rc = 0;
421 	struct smb_hdr *smb_buf;
422 	SESSION_SETUP_ANDX *pSMB;
423 	char *bcc_ptr;
424 	struct cifs_ses *ses = sess_data->ses;
425 	struct TCP_Server_Info *server = sess_data->server;
426 	__u32 capabilities;
427 	__u16 bytes_remaining;
428 
429 	/* old style NTLM sessionsetup */
430 	/* wct = 13 */
431 	rc = sess_alloc_buffer(sess_data, 13);
432 	if (rc)
433 		goto out;
434 
435 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
436 	bcc_ptr = sess_data->iov[2].iov_base;
437 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
438 
439 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
440 
441 	/* LM2 password would be here if we supported it */
442 	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
443 
444 	if (ses->user_name != NULL) {
445 		/* calculate nlmv2 response and session key */
446 		rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
447 		if (rc) {
448 			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
449 			goto out;
450 		}
451 
452 		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
453 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
454 		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
455 
456 		/* set case sensitive password length after tilen may get
457 		 * assigned, tilen is 0 otherwise.
458 		 */
459 		pSMB->req_no_secext.CaseSensitivePasswordLength =
460 			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
461 	} else {
462 		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
463 	}
464 
465 	if (ses->capabilities & CAP_UNICODE) {
466 		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
467 			*bcc_ptr = 0;
468 			bcc_ptr++;
469 		}
470 		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
471 	} else {
472 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
473 	}
474 
475 
476 	sess_data->iov[2].iov_len = (long) bcc_ptr -
477 			(long) sess_data->iov[2].iov_base;
478 
479 	rc = sess_sendreceive(sess_data);
480 	if (rc)
481 		goto out;
482 
483 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
484 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
485 
486 	if (smb_buf->WordCount != 3) {
487 		rc = smb_EIO1(smb_eio_trace_sess_nl2_wcc, smb_buf->WordCount);
488 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
489 		goto out;
490 	}
491 
492 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
493 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
494 
495 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
496 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
497 
498 	bytes_remaining = get_bcc(smb_buf);
499 	bcc_ptr = pByteArea(smb_buf);
500 
501 	/* BB check if Unicode and decode strings */
502 	if (bytes_remaining == 0) {
503 		/* no string area to decode, do nothing */
504 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
505 		/* unicode string area must be word-aligned */
506 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
507 			++bcc_ptr;
508 			--bytes_remaining;
509 		}
510 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
511 				      sess_data->nls_cp);
512 	} else {
513 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
514 				    sess_data->nls_cp);
515 	}
516 
517 	rc = sess_establish_session(sess_data);
518 out:
519 	sess_data->result = rc;
520 	sess_data->func = NULL;
521 	sess_free_buffer(sess_data);
522 	kfree_sensitive(ses->auth_key.response);
523 	ses->auth_key.response = NULL;
524 }
525 
526 #ifdef CONFIG_CIFS_UPCALL
527 static void
sess_auth_kerberos(struct sess_data * sess_data)528 sess_auth_kerberos(struct sess_data *sess_data)
529 {
530 	int rc = 0;
531 	struct smb_hdr *smb_buf;
532 	SESSION_SETUP_ANDX *pSMB;
533 	char *bcc_ptr;
534 	struct cifs_ses *ses = sess_data->ses;
535 	struct TCP_Server_Info *server = sess_data->server;
536 	__u32 capabilities;
537 	__u16 bytes_remaining;
538 	struct key *spnego_key = NULL;
539 	struct cifs_spnego_msg *msg;
540 	u16 blob_len;
541 
542 	/* extended security */
543 	/* wct = 12 */
544 	rc = sess_alloc_buffer(sess_data, 12);
545 	if (rc)
546 		goto out;
547 
548 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
549 	bcc_ptr = sess_data->iov[2].iov_base;
550 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
551 
552 	spnego_key = cifs_get_spnego_key(ses, server);
553 	if (IS_ERR(spnego_key)) {
554 		rc = PTR_ERR(spnego_key);
555 		spnego_key = NULL;
556 		goto out;
557 	}
558 
559 	msg = spnego_key->payload.data[0];
560 	/*
561 	 * check version field to make sure that cifs.upcall is
562 	 * sending us a response in an expected form
563 	 */
564 	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
565 		cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
566 			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
567 		rc = -EKEYREJECTED;
568 		goto out_put_spnego_key;
569 	}
570 
571 	kfree_sensitive(ses->auth_key.response);
572 	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
573 					 GFP_KERNEL);
574 	if (!ses->auth_key.response) {
575 		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
576 			 msg->sesskey_len);
577 		rc = -ENOMEM;
578 		goto out_put_spnego_key;
579 	}
580 	ses->auth_key.len = msg->sesskey_len;
581 
582 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
583 	capabilities |= CAP_EXTENDED_SECURITY;
584 	pSMB->req.Capabilities = cpu_to_le32(capabilities);
585 	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
586 	sess_data->iov[1].iov_len = msg->secblob_len;
587 	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
588 
589 	if (pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) {
590 		/* unicode strings must be word aligned */
591 		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
592 			*bcc_ptr = 0;
593 			bcc_ptr++;
594 		}
595 		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
596 		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
597 	} else {
598 		ascii_oslm_strings(&bcc_ptr, sess_data->nls_cp);
599 		ascii_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
600 	}
601 
602 	sess_data->iov[2].iov_len = (long) bcc_ptr -
603 			(long) sess_data->iov[2].iov_base;
604 
605 	rc = sess_sendreceive(sess_data);
606 	if (rc)
607 		goto out_put_spnego_key;
608 
609 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
610 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
611 
612 	if (smb_buf->WordCount != 4) {
613 		rc = smb_EIO1(smb_eio_trace_sess_krb_wcc, smb_buf->WordCount);
614 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
615 		goto out_put_spnego_key;
616 	}
617 
618 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
619 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
620 
621 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
622 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
623 
624 	bytes_remaining = get_bcc(smb_buf);
625 	bcc_ptr = pByteArea(smb_buf);
626 
627 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
628 	if (blob_len > bytes_remaining) {
629 		cifs_dbg(VFS, "bad security blob length %d\n",
630 				blob_len);
631 		rc = -EINVAL;
632 		goto out_put_spnego_key;
633 	}
634 	bcc_ptr += blob_len;
635 	bytes_remaining -= blob_len;
636 
637 	/* BB check if Unicode and decode strings */
638 	if (bytes_remaining == 0) {
639 		/* no string area to decode, do nothing */
640 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
641 		/* unicode string area must be word-aligned */
642 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
643 			++bcc_ptr;
644 			--bytes_remaining;
645 		}
646 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
647 				      sess_data->nls_cp);
648 	} else {
649 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
650 				    sess_data->nls_cp);
651 	}
652 
653 	rc = sess_establish_session(sess_data);
654 out_put_spnego_key:
655 	key_invalidate(spnego_key);
656 	key_put(spnego_key);
657 out:
658 	sess_data->result = rc;
659 	sess_data->func = NULL;
660 	sess_free_buffer(sess_data);
661 	kfree_sensitive(ses->auth_key.response);
662 	ses->auth_key.response = NULL;
663 }
664 
665 #endif /* ! CONFIG_CIFS_UPCALL */
666 
667 /*
668  * The required kvec buffers have to be allocated before calling this
669  * function.
670  */
671 static int
_sess_auth_rawntlmssp_assemble_req(struct sess_data * sess_data)672 _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
673 {
674 	SESSION_SETUP_ANDX *pSMB;
675 	struct cifs_ses *ses = sess_data->ses;
676 	struct TCP_Server_Info *server = sess_data->server;
677 	__u32 capabilities;
678 	char *bcc_ptr;
679 
680 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
681 
682 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
683 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
684 	capabilities |= CAP_EXTENDED_SECURITY;
685 	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
686 
687 	bcc_ptr = sess_data->iov[2].iov_base;
688 
689 	if (pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) {
690 		/* unicode strings must be word aligned */
691 		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
692 			*bcc_ptr = 0;
693 			bcc_ptr++;
694 		}
695 		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
696 	} else {
697 		ascii_oslm_strings(&bcc_ptr, sess_data->nls_cp);
698 	}
699 
700 	sess_data->iov[2].iov_len = (long) bcc_ptr -
701 					(long) sess_data->iov[2].iov_base;
702 
703 	return 0;
704 }
705 
706 static void
707 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
708 
709 static void
sess_auth_rawntlmssp_negotiate(struct sess_data * sess_data)710 sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
711 {
712 	int rc;
713 	struct smb_hdr *smb_buf;
714 	SESSION_SETUP_ANDX *pSMB;
715 	struct cifs_ses *ses = sess_data->ses;
716 	struct TCP_Server_Info *server = sess_data->server;
717 	__u16 bytes_remaining;
718 	char *bcc_ptr;
719 	unsigned char *ntlmsspblob = NULL;
720 	u16 blob_len;
721 
722 	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
723 
724 	/*
725 	 * if memory allocation is successful, caller of this function
726 	 * frees it.
727 	 */
728 	ses->ntlmssp = kmalloc_obj(struct ntlmssp_auth);
729 	if (!ses->ntlmssp) {
730 		rc = -ENOMEM;
731 		goto out;
732 	}
733 	ses->ntlmssp->sesskey_per_smbsess = false;
734 
735 	/* wct = 12 */
736 	rc = sess_alloc_buffer(sess_data, 12);
737 	if (rc)
738 		goto out;
739 
740 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
741 
742 	/* Build security blob before we assemble the request */
743 	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
744 				     &blob_len, ses, server,
745 				     sess_data->nls_cp);
746 	if (rc)
747 		goto out_free_ntlmsspblob;
748 
749 	sess_data->iov[1].iov_len = blob_len;
750 	sess_data->iov[1].iov_base = ntlmsspblob;
751 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
752 
753 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
754 	if (rc)
755 		goto out_free_ntlmsspblob;
756 
757 	rc = sess_sendreceive(sess_data);
758 
759 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
760 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
761 
762 	/* If true, rc here is expected and not an error */
763 	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
764 	    smb_buf->Status.CifsError ==
765 			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
766 		rc = 0;
767 
768 	if (rc)
769 		goto out_free_ntlmsspblob;
770 
771 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
772 
773 	if (smb_buf->WordCount != 4) {
774 		rc = smb_EIO1(smb_eio_trace_sess_rawnl_neg_wcc, smb_buf->WordCount);
775 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
776 		goto out_free_ntlmsspblob;
777 	}
778 
779 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
780 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
781 
782 	bytes_remaining = get_bcc(smb_buf);
783 	bcc_ptr = pByteArea(smb_buf);
784 
785 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
786 	if (blob_len > bytes_remaining) {
787 		cifs_dbg(VFS, "bad security blob length %d\n",
788 				blob_len);
789 		rc = -EINVAL;
790 		goto out_free_ntlmsspblob;
791 	}
792 
793 	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
794 
795 out_free_ntlmsspblob:
796 	kfree_sensitive(ntlmsspblob);
797 out:
798 	sess_free_buffer(sess_data);
799 
800 	if (!rc) {
801 		sess_data->func = sess_auth_rawntlmssp_authenticate;
802 		return;
803 	}
804 
805 	/* Else error. Cleanup */
806 	kfree_sensitive(ses->auth_key.response);
807 	ses->auth_key.response = NULL;
808 	kfree_sensitive(ses->ntlmssp);
809 	ses->ntlmssp = NULL;
810 
811 	sess_data->func = NULL;
812 	sess_data->result = rc;
813 }
814 
815 static void
sess_auth_rawntlmssp_authenticate(struct sess_data * sess_data)816 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
817 {
818 	int rc;
819 	struct smb_hdr *smb_buf;
820 	SESSION_SETUP_ANDX *pSMB;
821 	struct cifs_ses *ses = sess_data->ses;
822 	struct TCP_Server_Info *server = sess_data->server;
823 	__u16 bytes_remaining;
824 	char *bcc_ptr;
825 	unsigned char *ntlmsspblob = NULL;
826 	u16 blob_len;
827 
828 	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
829 
830 	/* wct = 12 */
831 	rc = sess_alloc_buffer(sess_data, 12);
832 	if (rc)
833 		goto out;
834 
835 	/* Build security blob before we assemble the request */
836 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
837 	smb_buf = (struct smb_hdr *)pSMB;
838 	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
839 					&blob_len, ses, server,
840 					sess_data->nls_cp);
841 	if (rc)
842 		goto out_free_ntlmsspblob;
843 	sess_data->iov[1].iov_len = blob_len;
844 	sess_data->iov[1].iov_base = ntlmsspblob;
845 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
846 	/*
847 	 * Make sure that we tell the server that we are using
848 	 * the uid that it just gave us back on the response
849 	 * (challenge)
850 	 */
851 	smb_buf->Uid = ses->Suid;
852 
853 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
854 	if (rc)
855 		goto out_free_ntlmsspblob;
856 
857 	rc = sess_sendreceive(sess_data);
858 	if (rc)
859 		goto out_free_ntlmsspblob;
860 
861 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
862 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
863 	if (smb_buf->WordCount != 4) {
864 		rc = smb_EIO1(smb_eio_trace_sess_rawnl_auth_wcc, smb_buf->WordCount);
865 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
866 		goto out_free_ntlmsspblob;
867 	}
868 
869 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
870 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
871 
872 	if (ses->Suid != smb_buf->Uid) {
873 		ses->Suid = smb_buf->Uid;
874 		cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
875 	}
876 
877 	bytes_remaining = get_bcc(smb_buf);
878 	bcc_ptr = pByteArea(smb_buf);
879 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
880 	if (blob_len > bytes_remaining) {
881 		cifs_dbg(VFS, "bad security blob length %d\n",
882 				blob_len);
883 		rc = -EINVAL;
884 		goto out_free_ntlmsspblob;
885 	}
886 	bcc_ptr += blob_len;
887 	bytes_remaining -= blob_len;
888 
889 
890 	/* BB check if Unicode and decode strings */
891 	if (bytes_remaining == 0) {
892 		/* no string area to decode, do nothing */
893 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
894 		/* unicode string area must be word-aligned */
895 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
896 			++bcc_ptr;
897 			--bytes_remaining;
898 		}
899 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
900 				      sess_data->nls_cp);
901 	} else {
902 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
903 				    sess_data->nls_cp);
904 	}
905 
906 out_free_ntlmsspblob:
907 	kfree_sensitive(ntlmsspblob);
908 out:
909 	sess_free_buffer(sess_data);
910 
911 	if (!rc)
912 		rc = sess_establish_session(sess_data);
913 
914 	/* Cleanup */
915 	kfree_sensitive(ses->auth_key.response);
916 	ses->auth_key.response = NULL;
917 	kfree_sensitive(ses->ntlmssp);
918 	ses->ntlmssp = NULL;
919 
920 	sess_data->func = NULL;
921 	sess_data->result = rc;
922 }
923 
select_sec(struct sess_data * sess_data)924 static int select_sec(struct sess_data *sess_data)
925 {
926 	int type;
927 	struct cifs_ses *ses = sess_data->ses;
928 	struct TCP_Server_Info *server = sess_data->server;
929 
930 	type = cifs_select_sectype(server, ses->sectype);
931 	cifs_dbg(FYI, "sess setup type %d\n", type);
932 	if (type == Unspecified) {
933 		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
934 		return -EINVAL;
935 	}
936 
937 	switch (type) {
938 	case NTLMv2:
939 		sess_data->func = sess_auth_ntlmv2;
940 		break;
941 	case Kerberos:
942 #ifdef CONFIG_CIFS_UPCALL
943 		sess_data->func = sess_auth_kerberos;
944 		break;
945 #else
946 		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
947 		return -ENOSYS;
948 #endif /* CONFIG_CIFS_UPCALL */
949 	case RawNTLMSSP:
950 		sess_data->func = sess_auth_rawntlmssp_negotiate;
951 		break;
952 	default:
953 		cifs_dbg(VFS, "secType %d not supported!\n", type);
954 		return -ENOSYS;
955 	}
956 
957 	return 0;
958 }
959 
CIFS_SessSetup(const unsigned int xid,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)960 int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
961 		   struct TCP_Server_Info *server,
962 		   const struct nls_table *nls_cp)
963 {
964 	int rc = 0;
965 	struct sess_data *sess_data;
966 
967 	if (ses == NULL) {
968 		WARN(1, "%s: ses == NULL!", __func__);
969 		return -EINVAL;
970 	}
971 
972 	sess_data = kzalloc_obj(struct sess_data);
973 	if (!sess_data)
974 		return -ENOMEM;
975 
976 	sess_data->xid = xid;
977 	sess_data->ses = ses;
978 	sess_data->server = server;
979 	sess_data->buf0_type = CIFS_NO_BUFFER;
980 	sess_data->nls_cp = (struct nls_table *) nls_cp;
981 
982 	rc = select_sec(sess_data);
983 	if (rc)
984 		goto out;
985 
986 	while (sess_data->func)
987 		sess_data->func(sess_data);
988 
989 	/* Store result before we free sess_data */
990 	rc = sess_data->result;
991 
992 out:
993 	kfree_sensitive(sess_data);
994 	return rc;
995 }
996