1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/hfsplus/options.c
4 *
5 * Copyright (C) 2001
6 * Brad Boyer (flar@allandria.com)
7 * (C) 2003 Ardis Technologies <roman@ardistech.com>
8 *
9 * Option parsing
10 */
11
12#include <linux/string.h>
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/fs_struct.h>
16#include <linux/fs_context.h>
17#include <linux/fs_parser.h>
18#include <linux/nls.h>
19#include <linux/mount.h>
20#include <linux/seq_file.h>
21#include <linux/slab.h>
22#include "hfsplus_fs.h"
23
24enum {
25 opt_creator, opt_type,
26 opt_umask, opt_uid, opt_gid,
27 opt_part, opt_session, opt_nls,
28 opt_decompose, opt_barrier,
29 opt_force,
30};
31
32static const struct fs_parameter_spec hfs_param_spec[] = {
33 fsparam_string ("creator", opt_creator),
34 fsparam_string ("type", opt_type),
35 fsparam_u32oct ("umask", opt_umask),
36 fsparam_u32 ("uid", opt_uid),
37 fsparam_u32 ("gid", opt_gid),
38 fsparam_u32 ("part", opt_part),
39 fsparam_u32 ("session", opt_session),
40 fsparam_string ("nls", opt_nls),
41 fsparam_flag_no ("decompose", opt_decompose),
42 fsparam_flag_no ("barrier", opt_barrier),
43 fsparam_flag ("force", opt_force),
44 {}
45};
46
47/* Initialize an options object to reasonable defaults */
48void hfsplus_fill_defaults(struct hfsplus_sb_info *opts)
49{
50 if (!opts)
51 return;
52
53 opts->creator = HFSPLUS_DEF_CR_TYPE;
54 opts->type = HFSPLUS_DEF_CR_TYPE;
55 opts->umask = current_umask();
56 opts->uid = current_uid();
57 opts->gid = current_gid();
58 opts->part = -1;
59 opts->session = -1;
60}
61
62/* Parse options from mount. Returns nonzero errno on failure */
63int hfsplus_parse_param(struct fs_context *fc, struct fs_parameter *param)
64{
65 struct hfsplus_sb_info *sbi = fc->s_fs_info;
66 struct fs_parse_result result;
67 int opt;
68
69 /*
70 * Only the force option is examined during remount, all others
71 * are ignored.
72 */
73 if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE &&
74 strncmp(param->key, "force", 5))
75 return 0;
76
77 opt = fs_parse(fc, desc: hfs_param_spec, param, result: &result);
78 if (opt < 0)
79 return opt;
80
81 switch (opt) {
82 case opt_creator:
83 if (strlen(param->string) != 4) {
84 pr_err("creator requires a 4 character value\n");
85 return -EINVAL;
86 }
87 memcpy(&sbi->creator, param->string, 4);
88 break;
89 case opt_type:
90 if (strlen(param->string) != 4) {
91 pr_err("type requires a 4 character value\n");
92 return -EINVAL;
93 }
94 memcpy(&sbi->type, param->string, 4);
95 break;
96 case opt_umask:
97 sbi->umask = (umode_t)result.uint_32;
98 break;
99 case opt_uid:
100 sbi->uid = result.uid;
101 set_bit(HFSPLUS_SB_UID, addr: &sbi->flags);
102 break;
103 case opt_gid:
104 sbi->gid = result.gid;
105 set_bit(HFSPLUS_SB_GID, addr: &sbi->flags);
106 break;
107 case opt_part:
108 sbi->part = result.uint_32;
109 break;
110 case opt_session:
111 sbi->session = result.uint_32;
112 break;
113 case opt_nls:
114 if (sbi->nls) {
115 pr_err("unable to change nls mapping\n");
116 return -EINVAL;
117 }
118 sbi->nls = load_nls(charset: param->string);
119 if (!sbi->nls) {
120 pr_err("unable to load nls mapping \"%s\"\n",
121 param->string);
122 return -EINVAL;
123 }
124 break;
125 case opt_decompose:
126 if (result.negated)
127 set_bit(HFSPLUS_SB_NODECOMPOSE, addr: &sbi->flags);
128 else
129 clear_bit(HFSPLUS_SB_NODECOMPOSE, addr: &sbi->flags);
130 break;
131 case opt_barrier:
132 if (result.negated)
133 set_bit(HFSPLUS_SB_NOBARRIER, addr: &sbi->flags);
134 else
135 clear_bit(HFSPLUS_SB_NOBARRIER, addr: &sbi->flags);
136 break;
137 case opt_force:
138 set_bit(HFSPLUS_SB_FORCE, addr: &sbi->flags);
139 break;
140 default:
141 return -EINVAL;
142 }
143
144 return 0;
145}
146
147int hfsplus_show_options(struct seq_file *seq, struct dentry *root)
148{
149 struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb: root->d_sb);
150
151 if (sbi->creator != HFSPLUS_DEF_CR_TYPE)
152 seq_show_option_n(seq, "creator", (char *)&sbi->creator, 4);
153 if (sbi->type != HFSPLUS_DEF_CR_TYPE)
154 seq_show_option_n(seq, "type", (char *)&sbi->type, 4);
155 seq_printf(m: seq, fmt: ",umask=%o,uid=%u,gid=%u", sbi->umask,
156 from_kuid_munged(to: &init_user_ns, uid: sbi->uid),
157 from_kgid_munged(to: &init_user_ns, gid: sbi->gid));
158 if (sbi->part >= 0)
159 seq_printf(m: seq, fmt: ",part=%u", sbi->part);
160 if (sbi->session >= 0)
161 seq_printf(m: seq, fmt: ",session=%u", sbi->session);
162 if (sbi->nls)
163 seq_printf(m: seq, fmt: ",nls=%s", sbi->nls->charset);
164 if (test_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags))
165 seq_puts(m: seq, s: ",nodecompose");
166 if (test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags))
167 seq_puts(m: seq, s: ",nobarrier");
168 return 0;
169}
170

source code of linux/fs/hfsplus/options.c