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