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  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
  4 *   Copyright (C) 2018 Namjae Jeon <linkinjeon@kernel.org>
  5 */
  6
  7#include <linux/user_namespace.h>
  8
  9#include "smb_common.h"
 10#include "server.h"
 11#include "misc.h"
 12#include "../common/smb2status.h"
 13#include "connection.h"
 14#include "ksmbd_work.h"
 15#include "mgmt/user_session.h"
 16#include "mgmt/user_config.h"
 17#include "mgmt/tree_connect.h"
 18#include "mgmt/share_config.h"
 19
 20/*for shortname implementation */
 21static const char *basechars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_-!@#$%";
 22#define MANGLE_BASE (strlen(basechars) - 1)
 23#define MAGIC_CHAR '~'
 24#define PERIOD '.'
 25#define mangle(V) ((char)(basechars[(V) % MANGLE_BASE]))
 26
 27struct smb_protocol {
 28	int		index;
 29	char		*name;
 30	char		*prot;
 31	__u16		prot_id;
 32};
 33
 34static struct smb_protocol smb1_protos[] = {
 35	{
 36		SMB21_PROT,
 37		"\2SMB 2.1",
 38		"SMB2_10",
 39		SMB21_PROT_ID
 40	},
 41	{
 42		SMB2X_PROT,
 43		"\2SMB 2.???",
 44		"SMB2_22",
 45		SMB2X_PROT_ID
 46	},
 47};
 48
 49static struct smb_protocol smb2_protos[] = {
 50	{
 51		SMB21_PROT,
 52		"\2SMB 2.1",
 53		"SMB2_10",
 54		SMB21_PROT_ID
 55	},
 56	{
 57		SMB30_PROT,
 58		"\2SMB 3.0",
 59		"SMB3_00",
 60		SMB30_PROT_ID
 61	},
 62	{
 63		SMB302_PROT,
 64		"\2SMB 3.02",
 65		"SMB3_02",
 66		SMB302_PROT_ID
 67	},
 68	{
 69		SMB311_PROT,
 70		"\2SMB 3.1.1",
 71		"SMB3_11",
 72		SMB311_PROT_ID
 73	},
 74};
 75
 76unsigned int ksmbd_server_side_copy_max_chunk_count(void)
 77{
 78	return 256;
 79}
 80
 81unsigned int ksmbd_server_side_copy_max_chunk_size(void)
 82{
 83	return (2U << 30) - 1;
 84}
 85
 86unsigned int ksmbd_server_side_copy_max_total_size(void)
 87{
 88	return (2U << 30) - 1;
 89}
 90
 91inline int ksmbd_min_protocol(void)
 92{
 93	return SMB21_PROT;
 94}
 95
 96inline int ksmbd_max_protocol(void)
 97{
 98	return SMB311_PROT;
 99}
100
101int ksmbd_lookup_protocol_idx(char *str)
102{
103	int offt = ARRAY_SIZE(smb1_protos) - 1;
104	int len = strlen(str);
105
106	while (offt >= 0) {
107		if (!strncmp(str, smb1_protos[offt].prot, len)) {
108			ksmbd_debug(SMB, "selected %s dialect idx = %d\n",
109				    smb1_protos[offt].prot, offt);
110			return smb1_protos[offt].index;
111		}
112		offt--;
113	}
114
115	offt = ARRAY_SIZE(smb2_protos) - 1;
116	while (offt >= 0) {
117		if (!strncmp(str, smb2_protos[offt].prot, len)) {
118			ksmbd_debug(SMB, "selected %s dialect idx = %d\n",
119				    smb2_protos[offt].prot, offt);
120			return smb2_protos[offt].index;
121		}
122		offt--;
123	}
124	return -1;
125}
126
127/**
128 * ksmbd_verify_smb_message() - check for valid smb2 request header
129 * @work:	smb work
130 *
131 * check for valid smb signature and packet direction(request/response)
132 *
133 * Return:      0 on success, otherwise -EINVAL
134 */
135int ksmbd_verify_smb_message(struct ksmbd_work *work)
136{
137	struct smb2_hdr *smb2_hdr = ksmbd_req_buf_next(work);
138	struct smb_hdr *hdr;
139
140	if (smb2_hdr->ProtocolId == SMB2_PROTO_NUMBER)
141		return ksmbd_smb2_check_message(work);
142
143	hdr = work->request_buf;
144	if (*(__le32 *)hdr->Protocol == SMB1_PROTO_NUMBER &&
145	    hdr->Command == SMB_COM_NEGOTIATE) {
146		work->conn->outstanding_credits++;
147		return 0;
148	}
149
150	return -EINVAL;
151}
152
153/**
154 * ksmbd_smb_request() - check for valid smb request type
155 * @conn:	connection instance
156 *
157 * Return:      true on success, otherwise false
158 */
159bool ksmbd_smb_request(struct ksmbd_conn *conn)
160{
161	__le32 *proto;
162
163	if (conn->request_buf[0] != 0)
164		return false;
165
166	proto = (__le32 *)smb2_get_msg(conn->request_buf);
167	if (*proto == SMB2_COMPRESSION_TRANSFORM_ID) {
168		pr_err_ratelimited("smb2 compression not support yet");
169		return false;
170	}
171
172	if (*proto != SMB1_PROTO_NUMBER &&
173	    *proto != SMB2_PROTO_NUMBER &&
174	    *proto != SMB2_TRANSFORM_PROTO_NUM)
175		return false;
176
177	return true;
178}
179
180static bool supported_protocol(int idx)
181{
182	if (idx == SMB2X_PROT &&
183	    (server_conf.min_protocol >= SMB21_PROT ||
184	     server_conf.max_protocol <= SMB311_PROT))
185		return true;
186
187	return (server_conf.min_protocol <= idx &&
188		idx <= server_conf.max_protocol);
189}
190
191static char *next_dialect(char *dialect, int *next_off, int bcount)
192{
193	dialect = dialect + *next_off;
194	*next_off = strnlen(dialect, bcount);
195	if (dialect[*next_off] != '\0')
196		return NULL;
197	return dialect;
198}
199
200static int ksmbd_lookup_dialect_by_name(char *cli_dialects, __le16 byte_count)
201{
202	int i, seq_num, bcount, next;
203	char *dialect;
204
205	for (i = ARRAY_SIZE(smb1_protos) - 1; i >= 0; i--) {
206		seq_num = 0;
207		next = 0;
208		dialect = cli_dialects;
209		bcount = le16_to_cpu(byte_count);
210		do {
211			dialect = next_dialect(dialect, &next, bcount);
212			if (!dialect)
213				break;
214			ksmbd_debug(SMB, "client requested dialect %s\n",
215				    dialect);
216			if (!strcmp(dialect, smb1_protos[i].name)) {
217				if (supported_protocol(smb1_protos[i].index)) {
218					ksmbd_debug(SMB,
219						    "selected %s dialect\n",
220						    smb1_protos[i].name);
221					if (smb1_protos[i].index == SMB1_PROT)
222						return seq_num;
223					return smb1_protos[i].prot_id;
224				}
225			}
226			seq_num++;
227			bcount -= (++next);
228		} while (bcount > 0);
229	}
230
231	return BAD_PROT_ID;
232}
233
234int ksmbd_lookup_dialect_by_id(__le16 *cli_dialects, __le16 dialects_count)
235{
236	int i;
237	int count;
238
239	for (i = ARRAY_SIZE(smb2_protos) - 1; i >= 0; i--) {
240		count = le16_to_cpu(dialects_count);
241		while (--count >= 0) {
242			ksmbd_debug(SMB, "client requested dialect 0x%x\n",
243				    le16_to_cpu(cli_dialects[count]));
244			if (le16_to_cpu(cli_dialects[count]) !=
245					smb2_protos[i].prot_id)
246				continue;
247
248			if (supported_protocol(smb2_protos[i].index)) {
249				ksmbd_debug(SMB, "selected %s dialect\n",
250					    smb2_protos[i].name);
251				return smb2_protos[i].prot_id;
252			}
253		}
254	}
255
256	return BAD_PROT_ID;
257}
258
259static int ksmbd_negotiate_smb_dialect(void *buf)
260{
261	int smb_buf_length = get_rfc1002_len(buf);
262	__le32 proto = ((struct smb2_hdr *)smb2_get_msg(buf))->ProtocolId;
263
264	if (proto == SMB2_PROTO_NUMBER) {
265		struct smb2_negotiate_req *req;
266		int smb2_neg_size =
267			offsetof(struct smb2_negotiate_req, Dialects);
268
269		req = (struct smb2_negotiate_req *)smb2_get_msg(buf);
270		if (smb2_neg_size > smb_buf_length)
271			goto err_out;
272
273		if (struct_size(req, Dialects, le16_to_cpu(req->DialectCount)) >
274		    smb_buf_length)
275			goto err_out;
276
277		return ksmbd_lookup_dialect_by_id(req->Dialects,
278						  req->DialectCount);
279	}
280
281	proto = *(__le32 *)((struct smb_hdr *)buf)->Protocol;
282	if (proto == SMB1_PROTO_NUMBER) {
283		struct smb_negotiate_req *req;
284
285		req = (struct smb_negotiate_req *)buf;
286		if (le16_to_cpu(req->ByteCount) < 2)
287			goto err_out;
288
289		if (offsetof(struct smb_negotiate_req, DialectsArray) - 4 +
290			le16_to_cpu(req->ByteCount) > smb_buf_length) {
291			goto err_out;
292		}
293
294		return ksmbd_lookup_dialect_by_name(req->DialectsArray,
295						    req->ByteCount);
296	}
297
298err_out:
299	return BAD_PROT_ID;
300}
301
302#define SMB_COM_NEGOTIATE_EX	0x0
303
304/**
305 * get_smb1_cmd_val() - get smb command value from smb header
306 * @work:	smb work containing smb header
307 *
308 * Return:      smb command value
309 */
310static u16 get_smb1_cmd_val(struct ksmbd_work *work)
311{
312	return SMB_COM_NEGOTIATE_EX;
313}
314
315/**
316 * init_smb1_rsp_hdr() - initialize smb negotiate response header
317 * @work:	smb work containing smb request
318 *
319 * Return:      0 on success, otherwise -EINVAL
320 */
321static int init_smb1_rsp_hdr(struct ksmbd_work *work)
322{
323	struct smb_hdr *rsp_hdr = (struct smb_hdr *)work->response_buf;
324	struct smb_hdr *rcv_hdr = (struct smb_hdr *)work->request_buf;
325
326	rsp_hdr->Command = SMB_COM_NEGOTIATE;
327	*(__le32 *)rsp_hdr->Protocol = SMB1_PROTO_NUMBER;
328	rsp_hdr->Flags = SMBFLG_RESPONSE;
329	rsp_hdr->Flags2 = SMBFLG2_UNICODE | SMBFLG2_ERR_STATUS |
330		SMBFLG2_EXT_SEC | SMBFLG2_IS_LONG_NAME;
331	rsp_hdr->Pid = rcv_hdr->Pid;
332	rsp_hdr->Mid = rcv_hdr->Mid;
333	return 0;
334}
335
336/**
337 * smb1_check_user_session() - check for valid session for a user
338 * @work:	smb work containing smb request buffer
339 *
340 * Return:      0 on success, otherwise error
341 */
342static int smb1_check_user_session(struct ksmbd_work *work)
343{
344	unsigned int cmd = work->conn->ops->get_cmd_val(work);
345
346	if (cmd == SMB_COM_NEGOTIATE_EX)
347		return 0;
348
349	return -EINVAL;
350}
351
352/**
353 * smb1_allocate_rsp_buf() - allocate response buffer for a command
354 * @work:	smb work containing smb request
355 *
356 * Return:      0 on success, otherwise -ENOMEM
357 */
358static int smb1_allocate_rsp_buf(struct ksmbd_work *work)
359{
360	work->response_buf = kzalloc(MAX_CIFS_SMALL_BUFFER_SIZE,
361			KSMBD_DEFAULT_GFP);
362	work->response_sz = MAX_CIFS_SMALL_BUFFER_SIZE;
363
364	if (!work->response_buf) {
365		pr_err("Failed to allocate %u bytes buffer\n",
366				MAX_CIFS_SMALL_BUFFER_SIZE);
367		return -ENOMEM;
368	}
369
370	return 0;
371}
372
373/**
374 * set_smb1_rsp_status() - set error type in smb response header
375 * @work:	smb work containing smb response header
376 * @err:	error code to set in response
377 */
378static void set_smb1_rsp_status(struct ksmbd_work *work, __le32 err)
379{
380	work->send_no_response = 1;
381}
382
383static struct smb_version_ops smb1_server_ops = {
384	.get_cmd_val = get_smb1_cmd_val,
385	.init_rsp_hdr = init_smb1_rsp_hdr,
386	.allocate_rsp_buf = smb1_allocate_rsp_buf,
387	.check_user_session = smb1_check_user_session,
388	.set_rsp_status = set_smb1_rsp_status,
389};
390
391static struct smb_version_values smb1_server_values = {
392	.max_credits = SMB2_MAX_CREDITS,
393};
394
395static int smb1_negotiate(struct ksmbd_work *work)
396{
397	return ksmbd_smb_negotiate_common(work, SMB_COM_NEGOTIATE);
398}
399
400static struct smb_version_cmds smb1_server_cmds[1] = {
401	[SMB_COM_NEGOTIATE_EX]	= { .proc = smb1_negotiate, },
402};
403
404static int init_smb1_server(struct ksmbd_conn *conn)
405{
406	conn->vals = &smb1_server_values;
407	conn->ops = &smb1_server_ops;
408	conn->cmds = smb1_server_cmds;
409	conn->max_cmds = ARRAY_SIZE(smb1_server_cmds);
410	return 0;
411}
412
413int ksmbd_init_smb_server(struct ksmbd_conn *conn)
414{
415	__le32 proto;
416
417	proto = *(__le32 *)((struct smb_hdr *)conn->request_buf)->Protocol;
418	if (conn->need_neg == false) {
419		if (proto == SMB1_PROTO_NUMBER)
420			return -EINVAL;
421		return 0;
422	}
423
424	if (proto == SMB1_PROTO_NUMBER)
425		return init_smb1_server(conn);
426	return init_smb3_11_server(conn);
427}
428
429int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work, int info_level,
430				      struct ksmbd_file *dir,
431				      struct ksmbd_dir_info *d_info,
432				      char *search_pattern,
433				      int (*fn)(struct ksmbd_conn *, int,
434						struct ksmbd_dir_info *,
435						struct ksmbd_kstat *))
436{
437	int i, rc = 0;
438	struct ksmbd_conn *conn = work->conn;
439	struct mnt_idmap *idmap = file_mnt_idmap(dir->filp);
440
441	for (i = 0; i < 2; i++) {
442		struct kstat kstat;
443		struct ksmbd_kstat ksmbd_kstat;
444		struct dentry *dentry;
445
446		if (!dir->dot_dotdot[i]) { /* fill dot entry info */
447			if (i == 0) {
448				d_info->name = ".";
449				d_info->name_len = 1;
450				dentry = dir->filp->f_path.dentry;
451			} else {
452				d_info->name = "..";
453				d_info->name_len = 2;
454				dentry = dir->filp->f_path.dentry->d_parent;
455			}
456
457			if (!match_pattern(d_info->name, d_info->name_len,
458					   search_pattern)) {
459				dir->dot_dotdot[i] = 1;
460				continue;
461			}
462
463			ksmbd_kstat.kstat = &kstat;
464			rc = ksmbd_vfs_fill_dentry_attrs(work,
465							 idmap,
466							 dentry,
467							 &ksmbd_kstat);
468			if (rc)
469				break;
470
471			rc = fn(conn, info_level, d_info, &ksmbd_kstat);
472			if (rc)
473				break;
474			if (d_info->out_buf_len <= 0)
475				break;
476
477			dir->dot_dotdot[i] = 1;
478			if (d_info->flags & SMB2_RETURN_SINGLE_ENTRY) {
479				d_info->out_buf_len = 0;
480				break;
481			}
482		}
483	}
484
485	return rc;
486}
487
488/**
489 * ksmbd_extract_shortname() - get shortname from long filename
490 * @conn:	connection instance
491 * @longname:	source long filename
492 * @shortname:	destination short filename
493 *
494 * Return:	shortname length or 0 when source long name is '.' or '..'
495 * TODO: Though this function conforms the restriction of 8.3 Filename spec,
496 * but the result is different with Windows 7's one. need to check.
497 */
498int ksmbd_extract_shortname(struct ksmbd_conn *conn, const char *longname,
499			    char *shortname)
500{
501	const char *p;
502	char base[9], extension[4];
503	char out[13] = {0};
504	int baselen = 0;
505	int extlen = 0, len = 0;
506	unsigned int csum = 0;
507	const unsigned char *ptr;
508	bool dot_present = true;
509
510	p = longname;
511	if ((*p == '.') || (!(strcmp(p, "..")))) {
512		/*no mangling required */
513		return 0;
514	}
515
516	p = strrchr(longname, '.');
517	if (p == longname) { /*name starts with a dot*/
518		strscpy(extension, "___", strlen("___"));
519	} else {
520		if (p) {
521			p++;
522			while (*p && extlen < 3) {
523				if (*p != '.')
524					extension[extlen++] = toupper(*p);
525				p++;
526			}
527			extension[extlen] = '\0';
528		} else {
529			dot_present = false;
530		}
531	}
532
533	p = longname;
534	if (*p == '.') {
535		p++;
536		longname++;
537	}
538	while (*p && (baselen < 5)) {
539		if (*p != '.')
540			base[baselen++] = toupper(*p);
541		p++;
542	}
543
544	base[baselen] = MAGIC_CHAR;
545	memcpy(out, base, baselen + 1);
546
547	ptr = longname;
548	len = strlen(longname);
549	for (; len > 0; len--, ptr++)
550		csum += *ptr;
551
552	csum = csum % (MANGLE_BASE * MANGLE_BASE);
553	out[baselen + 1] = mangle(csum / MANGLE_BASE);
554	out[baselen + 2] = mangle(csum);
555	out[baselen + 3] = PERIOD;
556
557	if (dot_present)
558		memcpy(out + baselen + 4, extension, 4);
559	else
560		out[baselen + 4] = '\0';
561	smbConvertToUTF16((__le16 *)shortname, out, PATH_MAX,
562			  conn->local_nls, 0);
563	len = strlen(out) * 2;
564	return len;
565}
566
567static int __smb2_negotiate(struct ksmbd_conn *conn)
568{
569	return (conn->dialect >= SMB20_PROT_ID &&
570		conn->dialect <= SMB311_PROT_ID);
571}
572
573static int smb_handle_negotiate(struct ksmbd_work *work)
574{
575	struct smb_negotiate_rsp *neg_rsp = work->response_buf;
576
577	ksmbd_debug(SMB, "Unsupported SMB1 protocol\n");
578
579	if (ksmbd_iov_pin_rsp(work, (void *)neg_rsp + 4,
580			      sizeof(struct smb_negotiate_rsp) - 4))
581		return -ENOMEM;
582
583	neg_rsp->hdr.Status.CifsError = STATUS_SUCCESS;
584	neg_rsp->hdr.WordCount = 1;
585	neg_rsp->DialectIndex = cpu_to_le16(work->conn->dialect);
586	neg_rsp->ByteCount = 0;
587	return 0;
588}
589
590int ksmbd_smb_negotiate_common(struct ksmbd_work *work, unsigned int command)
591{
592	struct ksmbd_conn *conn = work->conn;
593	int ret;
594
595	conn->dialect =
596		ksmbd_negotiate_smb_dialect(work->request_buf);
597	ksmbd_debug(SMB, "conn->dialect 0x%x\n", conn->dialect);
598
599	if (command == SMB2_NEGOTIATE_HE) {
600		ret = smb2_handle_negotiate(work);
601		return ret;
602	}
603
604	if (command == SMB_COM_NEGOTIATE) {
605		if (__smb2_negotiate(conn)) {
606			init_smb3_11_server(conn);
607			init_smb2_neg_rsp(work);
608			ksmbd_debug(SMB, "Upgrade to SMB2 negotiation\n");
609			return 0;
610		}
611		return smb_handle_negotiate(work);
612	}
613
614	pr_err("Unknown SMB negotiation command: %u\n", command);
615	return -EINVAL;
616}
617
618enum SHARED_MODE_ERRORS {
619	SHARE_DELETE_ERROR,
620	SHARE_READ_ERROR,
621	SHARE_WRITE_ERROR,
622	FILE_READ_ERROR,
623	FILE_WRITE_ERROR,
624	FILE_DELETE_ERROR,
625};
626
627static const char * const shared_mode_errors[] = {
628	"Current access mode does not permit SHARE_DELETE",
629	"Current access mode does not permit SHARE_READ",
630	"Current access mode does not permit SHARE_WRITE",
631	"Desired access mode does not permit FILE_READ",
632	"Desired access mode does not permit FILE_WRITE",
633	"Desired access mode does not permit FILE_DELETE",
634};
635
636static void smb_shared_mode_error(int error, struct ksmbd_file *prev_fp,
637				  struct ksmbd_file *curr_fp)
638{
639	ksmbd_debug(SMB, "%s\n", shared_mode_errors[error]);
640	ksmbd_debug(SMB, "Current mode: 0x%x Desired mode: 0x%x\n",
641		    prev_fp->saccess, curr_fp->daccess);
642}
643
644int ksmbd_smb_check_shared_mode(struct file *filp, struct ksmbd_file *curr_fp)
645{
646	int rc = 0;
647	struct ksmbd_file *prev_fp;
648
649	/*
650	 * Lookup fp in master fp list, and check desired access and
651	 * shared mode between previous open and current open.
652	 */
653	down_read(&curr_fp->f_ci->m_lock);
654	list_for_each_entry(prev_fp, &curr_fp->f_ci->m_fp_list, node) {
655		if (file_inode(filp) != file_inode(prev_fp->filp))
656			continue;
657
658		if (filp == prev_fp->filp)
659			continue;
660
661		if (ksmbd_stream_fd(prev_fp) && ksmbd_stream_fd(curr_fp))
662			if (strcmp(prev_fp->stream.name, curr_fp->stream.name))
663				continue;
664
665		if (prev_fp->attrib_only != curr_fp->attrib_only)
666			continue;
667
668		if (!(prev_fp->saccess & FILE_SHARE_DELETE_LE) &&
669		    curr_fp->daccess & FILE_DELETE_LE) {
670			smb_shared_mode_error(SHARE_DELETE_ERROR,
671					      prev_fp,
672					      curr_fp);
673			rc = -EPERM;
674			break;
675		}
676
677		/*
678		 * Only check FILE_SHARE_DELETE if stream opened and
679		 * normal file opened.
680		 */
681		if (ksmbd_stream_fd(prev_fp) && !ksmbd_stream_fd(curr_fp))
682			continue;
683
684		if (!(prev_fp->saccess & FILE_SHARE_READ_LE) &&
685		    curr_fp->daccess & (FILE_EXECUTE_LE | FILE_READ_DATA_LE)) {
686			smb_shared_mode_error(SHARE_READ_ERROR,
687					      prev_fp,
688					      curr_fp);
689			rc = -EPERM;
690			break;
691		}
692
693		if (!(prev_fp->saccess & FILE_SHARE_WRITE_LE) &&
694		    curr_fp->daccess & (FILE_WRITE_DATA_LE | FILE_APPEND_DATA_LE)) {
695			smb_shared_mode_error(SHARE_WRITE_ERROR,
696					      prev_fp,
697					      curr_fp);
698			rc = -EPERM;
699			break;
700		}
701
702		if (prev_fp->daccess & (FILE_EXECUTE_LE | FILE_READ_DATA_LE) &&
703		    !(curr_fp->saccess & FILE_SHARE_READ_LE)) {
704			smb_shared_mode_error(FILE_READ_ERROR,
705					      prev_fp,
706					      curr_fp);
707			rc = -EPERM;
708			break;
709		}
710
711		if (prev_fp->daccess & (FILE_WRITE_DATA_LE | FILE_APPEND_DATA_LE) &&
712		    !(curr_fp->saccess & FILE_SHARE_WRITE_LE)) {
713			smb_shared_mode_error(FILE_WRITE_ERROR,
714					      prev_fp,
715					      curr_fp);
716			rc = -EPERM;
717			break;
718		}
719
720		if (prev_fp->daccess & FILE_DELETE_LE &&
721		    !(curr_fp->saccess & FILE_SHARE_DELETE_LE)) {
722			smb_shared_mode_error(FILE_DELETE_ERROR,
723					      prev_fp,
724					      curr_fp);
725			rc = -EPERM;
726			break;
727		}
728	}
729	up_read(&curr_fp->f_ci->m_lock);
730
731	return rc;
732}
733
734bool is_asterisk(char *p)
735{
736	return p && p[0] == '*';
737}
738
739int __ksmbd_override_fsids(struct ksmbd_work *work,
740		struct ksmbd_share_config *share)
741{
742	struct ksmbd_session *sess = work->sess;
743	struct ksmbd_user *user = sess->user;
744	struct cred *cred;
745	struct group_info *gi;
746	unsigned int uid;
747	unsigned int gid;
748	int i;
749
750	uid = user_uid(user);
751	gid = user_gid(user);
752	if (share->force_uid != KSMBD_SHARE_INVALID_UID)
753		uid = share->force_uid;
754	if (share->force_gid != KSMBD_SHARE_INVALID_GID)
755		gid = share->force_gid;
756
757	cred = prepare_kernel_cred(&init_task);
758	if (!cred)
759		return -ENOMEM;
760
761	cred->fsuid = make_kuid(&init_user_ns, uid);
762	cred->fsgid = make_kgid(&init_user_ns, gid);
763
764	gi = groups_alloc(user->ngroups);
765	if (!gi) {
766		abort_creds(cred);
767		return -ENOMEM;
768	}
769
770	for (i = 0; i < user->ngroups; i++)
771		gi->gid[i] = make_kgid(&init_user_ns, user->sgid[i]);
772
773	if (user->ngroups)
774		groups_sort(gi);
775
776	set_groups(cred, gi);
777	put_group_info(gi);
778
779	if (!uid_eq(cred->fsuid, GLOBAL_ROOT_UID))
780		cred->cap_effective = cap_drop_fs_set(cred->cap_effective);
781
782	WARN_ON(work->saved_cred);
783	work->saved_cred = override_creds(cred);
784	if (!work->saved_cred) {
785		abort_creds(cred);
786		return -EINVAL;
787	}
788	return 0;
789}
790
791int ksmbd_override_fsids(struct ksmbd_work *work)
792{
793	return __ksmbd_override_fsids(work, work->tcon->share_conf);
794}
795
796void ksmbd_revert_fsids(struct ksmbd_work *work)
797{
798	const struct cred *cred;
799
800	WARN_ON(!work->saved_cred);
801
802	cred = current_cred();
803	revert_creds(work->saved_cred);
804	put_cred(cred);
805	work->saved_cred = NULL;
806}
807
808__le32 smb_map_generic_desired_access(__le32 daccess)
809{
810	if (daccess & FILE_GENERIC_READ_LE) {
811		daccess |= cpu_to_le32(GENERIC_READ_FLAGS);
812		daccess &= ~FILE_GENERIC_READ_LE;
813	}
814
815	if (daccess & FILE_GENERIC_WRITE_LE) {
816		daccess |= cpu_to_le32(GENERIC_WRITE_FLAGS);
817		daccess &= ~FILE_GENERIC_WRITE_LE;
818	}
819
820	if (daccess & FILE_GENERIC_EXECUTE_LE) {
821		daccess |= cpu_to_le32(GENERIC_EXECUTE_FLAGS);
822		daccess &= ~FILE_GENERIC_EXECUTE_LE;
823	}
824
825	if (daccess & FILE_GENERIC_ALL_LE) {
826		daccess |= cpu_to_le32(GENERIC_ALL_FLAGS);
827		daccess &= ~FILE_GENERIC_ALL_LE;
828	}
829
830	return daccess;
831}