1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
4 * Copyright (C) 2018 Samsung Electronics Co., Ltd.
5 */
6
7 #include <linux/kernel.h>
8 #include <linux/xattr.h>
9 #include <linux/fs.h>
10 #include <linux/unicode.h>
11
12 #include "misc.h"
13 #include "smb_common.h"
14 #include "connection.h"
15 #include "vfs.h"
16
17 #include "mgmt/share_config.h"
18
19 /**
20 * match_pattern() - compare a string with a pattern which might include
21 * wildcard '*' and '?'
22 * TODO : implement consideration about DOS_DOT, DOS_QM and DOS_STAR
23 *
24 * @str: string to compare with a pattern
25 * @len: string length
26 * @pattern: pattern string which might include wildcard '*' and '?'
27 *
28 * Return: 0 if pattern matched with the string, otherwise non zero value
29 */
match_pattern(const char * str,size_t len,const char * pattern)30 int match_pattern(const char *str, size_t len, const char *pattern)
31 {
32 const char *s = str;
33 const char *p = pattern;
34 bool star = false;
35
36 while (*s && len) {
37 switch (*p) {
38 case '?':
39 s++;
40 len--;
41 p++;
42 break;
43 case '*':
44 star = true;
45 str = s;
46 if (!*++p)
47 return true;
48 pattern = p;
49 break;
50 default:
51 if (tolower(*s) == tolower(*p)) {
52 s++;
53 len--;
54 p++;
55 } else {
56 if (!star)
57 return false;
58 str++;
59 s = str;
60 p = pattern;
61 }
62 break;
63 }
64 }
65
66 if (*p == '*')
67 ++p;
68 return !*p;
69 }
70
71 /*
72 * is_char_allowed() - check for valid character
73 * @ch: input character to be checked
74 *
75 * Return: 1 if char is allowed, otherwise 0
76 */
is_char_allowed(char ch)77 static inline int is_char_allowed(char ch)
78 {
79 /* check for control chars, wildcards etc. */
80 if (!(ch & 0x80) &&
81 (ch <= 0x1f ||
82 ch == '?' || ch == '"' || ch == '<' ||
83 ch == '>' || ch == '|' || ch == '*'))
84 return 0;
85
86 return 1;
87 }
88
ksmbd_validate_filename(char * filename)89 int ksmbd_validate_filename(char *filename)
90 {
91 while (*filename) {
92 char c = *filename;
93
94 filename++;
95 if (!is_char_allowed(c)) {
96 ksmbd_debug(VFS, "File name validation failed: 0x%x\n", c);
97 return -ENOENT;
98 }
99 }
100
101 return 0;
102 }
103
ksmbd_validate_stream_name(char * stream_name)104 static int ksmbd_validate_stream_name(char *stream_name)
105 {
106 while (*stream_name) {
107 char c = *stream_name;
108
109 stream_name++;
110 if (c == '/' || c == ':' || c == '\\') {
111 pr_err("Stream name validation failed: %c\n", c);
112 return -ENOENT;
113 }
114 }
115
116 return 0;
117 }
118
parse_stream_name(char * filename,char ** stream_name,int * s_type)119 int parse_stream_name(char *filename, char **stream_name, int *s_type)
120 {
121 char *stream_type;
122 char *s_name;
123 int rc = 0;
124
125 s_name = filename;
126 filename = strsep(&s_name, ":");
127 ksmbd_debug(SMB, "filename : %s, streams : %s\n", filename, s_name);
128 if (strchr(s_name, ':')) {
129 stream_type = s_name;
130 s_name = strsep(&stream_type, ":");
131
132 rc = ksmbd_validate_stream_name(s_name);
133 if (rc < 0) {
134 rc = -ENOENT;
135 goto out;
136 }
137
138 ksmbd_debug(SMB, "stream name : %s, stream type : %s\n", s_name,
139 stream_type);
140 if (!strncasecmp("$data", stream_type, 5))
141 *s_type = DATA_STREAM;
142 else if (!strncasecmp("$index_allocation", stream_type, 17))
143 *s_type = DIR_STREAM;
144 else
145 rc = -ENOENT;
146 }
147
148 *stream_name = s_name;
149 out:
150 return rc;
151 }
152
153 /**
154 * convert_to_nt_pathname() - extract and return windows path string
155 * whose share directory prefix was removed from file path
156 * @share: ksmbd_share_config pointer
157 * @path: path to report
158 *
159 * Return : windows path string or error
160 */
161
convert_to_nt_pathname(struct ksmbd_share_config * share,const struct path * path)162 char *convert_to_nt_pathname(struct ksmbd_share_config *share,
163 const struct path *path)
164 {
165 char *pathname, *ab_pathname, *nt_pathname;
166 int share_path_len = share->path_sz;
167
168 pathname = kmalloc(PATH_MAX, GFP_KERNEL);
169 if (!pathname)
170 return ERR_PTR(-EACCES);
171
172 ab_pathname = d_path(path, pathname, PATH_MAX);
173 if (IS_ERR(ab_pathname)) {
174 nt_pathname = ERR_PTR(-EACCES);
175 goto free_pathname;
176 }
177
178 if (strncmp(ab_pathname, share->path, share_path_len)) {
179 nt_pathname = ERR_PTR(-EACCES);
180 goto free_pathname;
181 }
182
183 nt_pathname = kzalloc(strlen(&ab_pathname[share_path_len]) + 2, GFP_KERNEL);
184 if (!nt_pathname) {
185 nt_pathname = ERR_PTR(-ENOMEM);
186 goto free_pathname;
187 }
188 if (ab_pathname[share_path_len] == '\0')
189 strcpy(nt_pathname, "/");
190 strcat(nt_pathname, &ab_pathname[share_path_len]);
191
192 ksmbd_conv_path_to_windows(nt_pathname);
193
194 free_pathname:
195 kfree(pathname);
196 return nt_pathname;
197 }
198
get_nlink(struct kstat * st)199 int get_nlink(struct kstat *st)
200 {
201 int nlink;
202
203 nlink = st->nlink;
204 if (S_ISDIR(st->mode))
205 nlink--;
206
207 return nlink;
208 }
209
ksmbd_conv_path_to_unix(char * path)210 void ksmbd_conv_path_to_unix(char *path)
211 {
212 strreplace(path, '\\', '/');
213 }
214
ksmbd_strip_last_slash(char * path)215 void ksmbd_strip_last_slash(char *path)
216 {
217 int len = strlen(path);
218
219 while (len && path[len - 1] == '/') {
220 path[len - 1] = '\0';
221 len--;
222 }
223 }
224
ksmbd_conv_path_to_windows(char * path)225 void ksmbd_conv_path_to_windows(char *path)
226 {
227 strreplace(path, '/', '\\');
228 }
229
ksmbd_casefold_sharename(struct unicode_map * um,const char * name)230 char *ksmbd_casefold_sharename(struct unicode_map *um, const char *name)
231 {
232 char *cf_name;
233 int cf_len;
234
235 cf_name = kzalloc(KSMBD_REQ_MAX_SHARE_NAME, GFP_KERNEL);
236 if (!cf_name)
237 return ERR_PTR(-ENOMEM);
238
239 if (IS_ENABLED(CONFIG_UNICODE) && um) {
240 const struct qstr q_name = {.name = name, .len = strlen(name)};
241
242 cf_len = utf8_casefold(um, &q_name, cf_name,
243 KSMBD_REQ_MAX_SHARE_NAME);
244 if (cf_len < 0)
245 goto out_ascii;
246
247 return cf_name;
248 }
249
250 out_ascii:
251 cf_len = strscpy(cf_name, name, KSMBD_REQ_MAX_SHARE_NAME);
252 if (cf_len < 0) {
253 kfree(cf_name);
254 return ERR_PTR(-E2BIG);
255 }
256
257 for (; *cf_name; ++cf_name)
258 *cf_name = isascii(*cf_name) ? tolower(*cf_name) : *cf_name;
259 return cf_name - cf_len;
260 }
261
262 /**
263 * ksmbd_extract_sharename() - get share name from tree connect request
264 * @um: pointer to a unicode_map structure for character encoding handling
265 * @treename: buffer containing tree name and share name
266 *
267 * Return: share name on success, otherwise error
268 */
ksmbd_extract_sharename(struct unicode_map * um,const char * treename)269 char *ksmbd_extract_sharename(struct unicode_map *um, const char *treename)
270 {
271 const char *name = treename, *pos = strrchr(name, '\\');
272
273 if (pos)
274 name = (pos + 1);
275
276 /* caller has to free the memory */
277 return ksmbd_casefold_sharename(um, name);
278 }
279
280 /**
281 * convert_to_unix_name() - convert windows name to unix format
282 * @share: ksmbd_share_config pointer
283 * @name: file name that is relative to share
284 *
285 * Return: converted name on success, otherwise NULL
286 */
convert_to_unix_name(struct ksmbd_share_config * share,const char * name)287 char *convert_to_unix_name(struct ksmbd_share_config *share, const char *name)
288 {
289 int no_slash = 0, name_len, path_len;
290 char *new_name;
291
292 if (name[0] == '/')
293 name++;
294
295 path_len = share->path_sz;
296 name_len = strlen(name);
297 new_name = kmalloc(path_len + name_len + 2, GFP_KERNEL);
298 if (!new_name)
299 return new_name;
300
301 memcpy(new_name, share->path, path_len);
302 if (new_name[path_len - 1] != '/') {
303 new_name[path_len] = '/';
304 no_slash = 1;
305 }
306
307 memcpy(new_name + path_len + no_slash, name, name_len);
308 path_len += name_len + no_slash;
309 new_name[path_len] = 0x00;
310 return new_name;
311 }
312
ksmbd_convert_dir_info_name(struct ksmbd_dir_info * d_info,const struct nls_table * local_nls,int * conv_len)313 char *ksmbd_convert_dir_info_name(struct ksmbd_dir_info *d_info,
314 const struct nls_table *local_nls,
315 int *conv_len)
316 {
317 char *conv;
318 int sz = min(4 * d_info->name_len, PATH_MAX);
319
320 if (!sz)
321 return NULL;
322
323 conv = kmalloc(sz, GFP_KERNEL);
324 if (!conv)
325 return NULL;
326
327 /* XXX */
328 *conv_len = smbConvertToUTF16((__le16 *)conv, d_info->name,
329 d_info->name_len, local_nls, 0);
330 *conv_len *= 2;
331
332 /* We allocate buffer twice bigger than needed. */
333 conv[*conv_len] = 0x00;
334 conv[*conv_len + 1] = 0x00;
335 return conv;
336 }
337
338 /*
339 * Convert the NT UTC (based 1601-01-01, in hundred nanosecond units)
340 * into Unix UTC (based 1970-01-01, in seconds).
341 */
ksmbd_NTtimeToUnix(__le64 ntutc)342 struct timespec64 ksmbd_NTtimeToUnix(__le64 ntutc)
343 {
344 struct timespec64 ts;
345
346 /* Subtract the NTFS time offset, then convert to 1s intervals. */
347 s64 t = le64_to_cpu(ntutc) - NTFS_TIME_OFFSET;
348 u64 abs_t;
349
350 /*
351 * Unfortunately can not use normal 64 bit division on 32 bit arch, but
352 * the alternative, do_div, does not work with negative numbers so have
353 * to special case them
354 */
355 if (t < 0) {
356 abs_t = -t;
357 ts.tv_nsec = do_div(abs_t, 10000000) * 100;
358 ts.tv_nsec = -ts.tv_nsec;
359 ts.tv_sec = -abs_t;
360 } else {
361 abs_t = t;
362 ts.tv_nsec = do_div(abs_t, 10000000) * 100;
363 ts.tv_sec = abs_t;
364 }
365
366 return ts;
367 }
368
369 /* Convert the Unix UTC into NT UTC. */
ksmbd_UnixTimeToNT(struct timespec64 t)370 inline u64 ksmbd_UnixTimeToNT(struct timespec64 t)
371 {
372 /* Convert to 100ns intervals and then add the NTFS time offset. */
373 return (u64)t.tv_sec * 10000000 + t.tv_nsec / 100 + NTFS_TIME_OFFSET;
374 }
375
ksmbd_systime(void)376 inline long long ksmbd_systime(void)
377 {
378 struct timespec64 ts;
379
380 ktime_get_real_ts64(&ts);
381 return ksmbd_UnixTimeToNT(ts);
382 }
383