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 24 enum { 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 32 static 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 */ 48 void 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 */ 63 int 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, hfs_param_spec, param, &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, &sbi->flags); 102 break; 103 case opt_gid: 104 sbi->gid = result.gid; 105 set_bit(HFSPLUS_SB_GID, &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(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, &sbi->flags); 128 else 129 clear_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags); 130 break; 131 case opt_barrier: 132 if (result.negated) 133 set_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags); 134 else 135 clear_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags); 136 break; 137 case opt_force: 138 set_bit(HFSPLUS_SB_FORCE, &sbi->flags); 139 break; 140 default: 141 return -EINVAL; 142 } 143 144 return 0; 145 } 146 147 int hfsplus_show_options(struct seq_file *seq, struct dentry *root) 148 { 149 struct hfsplus_sb_info *sbi = HFSPLUS_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(seq, ",umask=%o,uid=%u,gid=%u", sbi->umask, 156 from_kuid_munged(&init_user_ns, sbi->uid), 157 from_kgid_munged(&init_user_ns, sbi->gid)); 158 if (sbi->part >= 0) 159 seq_printf(seq, ",part=%u", sbi->part); 160 if (sbi->session >= 0) 161 seq_printf(seq, ",session=%u", sbi->session); 162 if (sbi->nls) 163 seq_printf(seq, ",nls=%s", sbi->nls->charset); 164 if (test_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags)) 165 seq_puts(seq, ",nodecompose"); 166 if (test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags)) 167 seq_puts(seq, ",nobarrier"); 168 return 0; 169 } 170