1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2020, Microsoft Corporation.
4 *
5 * Author(s): Steve French <stfrench@microsoft.com>
6 * Suresh Jayaraman <sjayaraman@suse.de>
7 * Jeff Layton <jlayton@kernel.org>
8 */
9
10 #include <linux/fs.h>
11 #include <linux/slab.h>
12 #include <linux/inet.h>
13 #include <linux/ctype.h>
14 #include "cifsglob.h"
15 #include "cifsproto.h"
16
17 /* extract the host portion of the UNC string */
18 char *extract_hostname(const char *unc)
19 {
20 const char *src;
21 char *dst, *delim;
22 unsigned int len;
23
24 /* skip double chars at beginning of string */
25 /* BB: check validity of these bytes? */
26 if (strlen(unc) < 3)
27 return ERR_PTR(-EINVAL);
28 for (src = unc; *src && *src == '\\'; src++)
29 ;
30 if (!*src)
31 return ERR_PTR(-EINVAL);
32
33 /* delimiter between hostname and sharename is always '\\' now */
34 delim = strchr(src, '\\');
35 if (!delim)
36 return ERR_PTR(-EINVAL);
37
38 len = delim - src;
39 dst = kmalloc((len + 1), GFP_KERNEL);
40 if (dst == NULL)
41 return ERR_PTR(-ENOMEM);
42
43 memcpy(dst, src, len);
44 dst[len] = '\0';
45
46 return dst;
47 }
48
49 char *extract_sharename(const char *unc)
50 {
51 const char *src;
52 char *delim, *dst;
53
54 /* skip double chars at the beginning */
55 src = unc + 2;
56
57 /* share name is always preceded by '\\' now */
58 delim = strchr(src, '\\');
59 if (!delim)
60 return ERR_PTR(-EINVAL);
61 delim++;
62
63 /* caller has to free the memory */
64 dst = kstrdup(delim, GFP_KERNEL);
65 if (!dst)
66 return ERR_PTR(-ENOMEM);
67
68 return dst;
69 }
70
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.