summaryrefslogtreecommitdiff
path: root/fs/smb/server/misc.c
blob: 9e8afaa686e3aa8c12e908348aa38b34168ec367 (plain)
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
31
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
77
78
79
80
81
82
83
84
85
86
87
88
89
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
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
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
170
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
252
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
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *   Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
 *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
 */

#include <linux/kernel.h>
#include <linux/xattr.h>
#include <linux/fs.h>
#include <linux/unicode.h>

#include "misc.h"
#include "smb_common.h"
#include "connection.h"
#include "vfs.h"

#include "mgmt/share_config.h"

/**
 * match_pattern() - compare a string with a pattern which might include
 * wildcard '*' and '?'
 * TODO : implement consideration about DOS_DOT, DOS_QM and DOS_STAR
 *
 * @str:	string to compare with a pattern
 * @len:	string length
 * @pattern:	pattern string which might include wildcard '*' and '?'
 *
 * Return:	0 if pattern matched with the string, otherwise non zero value
 */
int match_pattern(const char *str, size_t len, const char *pattern)
{
	const char *s = str;
	const char *p = pattern;
	bool star = false;

	while (*s && len) {
		switch (*p) {
		case '?':
			s++;
			len--;
			p++;
			break;
		case '*':
			star = true;
			str = s;
			if (!*++p)
				return true;
			pattern = p;
			break;
		default:
			if (tolower(*s) == tolower(*p)) {
				s++;
				len--;
				p++;
			} else {
				if (!star)
					return false;
				str++;
				s = str;
				p = pattern;
			}
			break;
		}
	}

	if (*p == '*')
		++p;
	return !*p;
}

/*
 * is_char_allowed() - check for valid character
 * @ch:		input character to be checked
 *
 * Return:	1 if char is allowed, otherwise 0
 */
static inline int is_char_allowed(char ch)
{
	/* check for control chars, wildcards etc. */
	if (!(ch & 0x80) &&
	    (ch <= 0x1f ||
	     ch == '?' || ch == '"' || ch == '<' ||
	     ch == '>' || ch == '|' || ch == '*'))
		return 0;

	return 1;
}

int ksmbd_validate_filename(char *filename)
{
	while (*filename) {
		char c = *filename;

		filename++;
		if (!is_char_allowed(c)) {
			ksmbd_debug(VFS, "File name validation failed: 0x%x\n", c);
			return -ENOENT;
		}
	}

	return 0;
}

static int ksmbd_validate_stream_name(char *stream_name)
{
	while (*stream_name) {
		char c = *stream_name;

		stream_name++;
		if (c == '/' || c == ':' || c == '\\') {
			pr_err("Stream name validation failed: %c\n", c);
			return -ENOENT;
		}
	}

	return 0;
}

int parse_stream_name(char *filename, char **stream_name, int *s_type)
{
	char *stream_type;
	char *s_name;
	int rc = 0;

	s_name = filename;
	filename = strsep(&s_name, ":");
	ksmbd_debug(SMB, "filename : %s, streams : %s\n", filename, s_name);
	if (strchr(s_name, ':')) {
		stream_type = s_name;
		s_name = strsep(&stream_type, ":");

		rc = ksmbd_validate_stream_name(s_name);
		if (rc < 0) {
			rc = -ENOENT;
			goto out;
		}

		ksmbd_debug(SMB, "stream name : %s, stream type : %s\n", s_name,
			    stream_type);
		if (!strncasecmp("$data", stream_type, 5))
			*s_type = DATA_STREAM;
		else if (!strncasecmp("$index_allocation", stream_type, 17))
			*s_type = DIR_STREAM;
		else
			rc = -ENOENT;
	}

	*stream_name = s_name;
out:
	return rc;
}

/**
 * convert_to_nt_pathname() - extract and return windows path string
 *      whose share directory prefix was removed from file path
 * @share: ksmbd_share_config pointer
 * @path: path to report
 *
 * Return : windows path string or error
 */

char *convert_to_nt_pathname(struct ksmbd_share_config *share,
			     const struct path *path)
{
	char *pathname, *ab_pathname, *nt_pathname;
	int share_path_len = share->path_sz;

	pathname = kmalloc(PATH_MAX, GFP_KERNEL);
	if (!pathname)
		return ERR_PTR(-EACCES);

	ab_pathname = d_path(path, pathname, PATH_MAX);
	if (IS_ERR(ab_pathname)) {
		nt_pathname = ERR_PTR(-EACCES);
		goto free_pathname;
	}

	if (strncmp(ab_pathname, share->path, share_path_len)) {
		nt_pathname = ERR_PTR(-EACCES);
		goto free_pathname;
	}

	nt_pathname = kzalloc(strlen(&ab_pathname[share_path_len]) + 2, GFP_KERNEL);
	if (!nt_pathname) {
		nt_pathname = ERR_PTR(-ENOMEM);
		goto free_pathname;
	}
	if (ab_pathname[share_path_len] == '\0')
		strcpy(nt_pathname, "/");
	strcat(nt_pathname, &ab_pathname[share_path_len]);

	ksmbd_conv_path_to_windows(nt_pathname);

free_pathname:
	kfree(pathname);
	return nt_pathname;
}

int get_nlink(struct kstat *st)
{
	int nlink;

	nlink = st->nlink;
	if (S_ISDIR(st->mode))
		nlink--;

	return nlink;
}

void ksmbd_conv_path_to_unix(char *path)
{
	strreplace(path, '\\', '/');
}

void ksmbd_strip_last_slash(char *path)
{
	int len = strlen(path);

	while (len && path[len - 1] == '/') {
		path[len - 1] = '\0';
		len--;
	}
}

void ksmbd_conv_path_to_windows(char *path)
{
	strreplace(path, '/', '\\');
}

char *ksmbd_casefold_sharename(struct unicode_map *um, const char *name)
{
	char *cf_name;
	int cf_len;

	cf_name = kzalloc(KSMBD_REQ_MAX_SHARE_NAME, GFP_KERNEL);
	if (!cf_name)
		return ERR_PTR(-ENOMEM);

	if (IS_ENABLED(CONFIG_UNICODE) && um) {
		const struct qstr q_name = {.name = name, .len = strlen(name)};

		cf_len = utf8_casefold(um, &q_name, cf_name,
				       KSMBD_REQ_MAX_SHARE_NAME);
		if (cf_len < 0)
			goto out_ascii;

		return cf_name;
	}

out_ascii:
	cf_len = strscpy(cf_name, name, KSMBD_REQ_MAX_SHARE_NAME);
	if (cf_len < 0) {
		kfree(cf_name);
		return ERR_PTR(-E2BIG);
	}

	for (; *cf_name; ++cf_name)
		*cf_name = isascii(*cf_name) ? tolower(*cf_name) : *cf_name;
	return cf_name - cf_len;
}

/**
 * ksmbd_extract_sharename() - get share name from tree connect request
 * @treename:	buffer containing tree name and share name
 *
 * Return:      share name on success, otherwise error
 */
char *ksmbd_extract_sharename(struct unicode_map *um, const char *treename)
{
	const char *name = treename, *pos = strrchr(name, '\\');

	if (pos)
		name = (pos + 1);

	/* caller has to free the memory */
	return ksmbd_casefold_sharename(um, name);
}

/**
 * convert_to_unix_name() - convert windows name to unix format
 * @share:	ksmbd_share_config pointer
 * @name:	file name that is relative to share
 *
 * Return:	converted name on success, otherwise NULL
 */
char *convert_to_unix_name(struct ksmbd_share_config *share, const char *name)
{
	int no_slash = 0, name_len, path_len;
	char *new_name;

	if (name[0] == '/')
		name++;

	path_len = share->path_sz;
	name_len = strlen(name);
	new_name = kmalloc(path_len + name_len + 2, GFP_KERNEL);
	if (!new_name)
		return new_name;

	memcpy(new_name, share->path, path_len);
	if (new_name[path_len - 1] != '/') {
		new_name[path_len] = '/';
		no_slash = 1;
	}

	memcpy(new_name + path_len + no_slash, name, name_len);
	path_len += name_len + no_slash;
	new_name[path_len] = 0x00;
	return new_name;
}

char *ksmbd_convert_dir_info_name(struct ksmbd_dir_info *d_info,
				  const struct nls_table *local_nls,
				  int *conv_len)
{
	char *conv;
	int  sz = min(4 * d_info->name_len, PATH_MAX);

	if (!sz)
		return NULL;

	conv = kmalloc(sz, GFP_KERNEL);
	if (!conv)
		return NULL;

	/* XXX */
	*conv_len = smbConvertToUTF16((__le16 *)conv, d_info->name,
				      d_info->name_len, local_nls, 0);
	*conv_len *= 2;

	/* We allocate buffer twice bigger than needed. */
	conv[*conv_len] = 0x00;
	conv[*conv_len + 1] = 0x00;
	return conv;
}

/*
 * Convert the NT UTC (based 1601-01-01, in hundred nanosecond units)
 * into Unix UTC (based 1970-01-01, in seconds).
 */
struct timespec64 ksmbd_NTtimeToUnix(__le64 ntutc)
{
	struct timespec64 ts;

	/* Subtract the NTFS time offset, then convert to 1s intervals. */
	s64 t = le64_to_cpu(ntutc) - NTFS_TIME_OFFSET;
	u64 abs_t;

	/*
	 * Unfortunately can not use normal 64 bit division on 32 bit arch, but
	 * the alternative, do_div, does not work with negative numbers so have
	 * to special case them
	 */
	if (t < 0) {
		abs_t = -t;
		ts.tv_nsec = do_div(abs_t, 10000000) * 100;
		ts.tv_nsec = -ts.tv_nsec;
		ts.tv_sec = -abs_t;
	} else {
		abs_t = t;
		ts.tv_nsec = do_div(abs_t, 10000000) * 100;
		ts.tv_sec = abs_t;
	}

	return ts;
}

/* Convert the Unix UTC into NT UTC. */
inline u64 ksmbd_UnixTimeToNT(struct timespec64 t)
{
	/* Convert to 100ns intervals and then add the NTFS time offset. */
	return (u64)t.tv_sec * 10000000 + t.tv_nsec / 100 + NTFS_TIME_OFFSET;
}

inline long long ksmbd_systime(void)
{
	struct timespec64	ts;

	ktime_get_real_ts64(&ts);
	return ksmbd_UnixTimeToNT(ts);
}