1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #include <linux/fs.h> 3 #include <linux/buffer_head.h> 4 #include <linux/exportfs.h> 5 #include <linux/iso_fs.h> 6 #include <linux/unaligned.h> 7 8 enum isofs_file_format { 9 isofs_file_normal = 0, 10 isofs_file_sparse = 1, 11 isofs_file_compressed = 2, 12 }; 13 14 /* 15 * iso fs inode data in memory 16 */ 17 struct iso_inode_info { 18 unsigned long i_iget5_block; 19 unsigned long i_iget5_offset; 20 unsigned int i_first_extent; 21 unsigned char i_file_format; 22 unsigned char i_format_parm[3]; 23 unsigned long i_next_section_block; 24 unsigned long i_next_section_offset; 25 off_t i_section_size; 26 struct inode vfs_inode; 27 }; 28 29 /* 30 * iso9660 super-block data in memory 31 */ 32 struct isofs_sb_info { 33 unsigned long s_ninodes; 34 unsigned long s_nzones; 35 unsigned long s_firstdatazone; 36 unsigned long s_log_zone_size; 37 unsigned long s_max_size; 38 /* Session start in filesystem block units. */ 39 sector_t s_session_start; 40 41 int s_rock_offset; /* offset of SUSP fields within SU area */ 42 s32 s_sbsector; 43 unsigned char s_joliet_level; 44 unsigned char s_mapping; 45 unsigned char s_check; 46 unsigned char s_session; 47 unsigned int s_high_sierra:1; 48 unsigned int s_rock:2; 49 unsigned int s_cruft:1; /* Broken disks with high byte of length 50 * containing junk */ 51 unsigned int s_nocompress:1; 52 unsigned int s_hide:1; 53 unsigned int s_showassoc:1; 54 unsigned int s_overriderockperm:1; 55 unsigned int s_uid_set:1; 56 unsigned int s_gid_set:1; 57 58 umode_t s_fmode; 59 umode_t s_dmode; 60 kgid_t s_gid; 61 kuid_t s_uid; 62 struct nls_table *s_nls_iocharset; /* Native language support table */ 63 }; 64 65 #define ISOFS_INVALID_MODE ((umode_t) -1) 66 67 static inline struct isofs_sb_info *ISOFS_SB(struct super_block *sb) 68 { 69 return sb->s_fs_info; 70 } 71 72 static inline struct iso_inode_info *ISOFS_I(struct inode *inode) 73 { 74 return container_of(inode, struct iso_inode_info, vfs_inode); 75 } 76 77 static inline int isonum_711(u8 *p) 78 { 79 return *p; 80 } 81 static inline int isonum_712(s8 *p) 82 { 83 return *p; 84 } 85 static inline unsigned int isonum_721(u8 *p) 86 { 87 return get_unaligned_le16(p); 88 } 89 static inline unsigned int isonum_722(u8 *p) 90 { 91 return get_unaligned_be16(p); 92 } 93 static inline unsigned int isonum_723(u8 *p) 94 { 95 /* Ignore bigendian datum due to broken mastering programs */ 96 return get_unaligned_le16(p); 97 } 98 static inline unsigned int isonum_731(u8 *p) 99 { 100 return get_unaligned_le32(p); 101 } 102 static inline unsigned int isonum_732(u8 *p) 103 { 104 return get_unaligned_be32(p); 105 } 106 static inline unsigned int isonum_733(u8 *p) 107 { 108 /* Ignore bigendian datum due to broken mastering programs */ 109 return get_unaligned_le32(p); 110 } 111 #define ISO_DATE_HIGH_SIERRA (1 << 0) 112 #define ISO_DATE_LONG_FORM (1 << 1) 113 struct timespec64 iso_date(u8 *p, int flags); 114 115 struct inode; /* To make gcc happy */ 116 117 extern int parse_rock_ridge_inode(struct iso_directory_record *, struct inode *, int relocated); 118 int get_rock_ridge_filename(struct iso_directory_record *de, char *retname, 119 int retnamesize, struct inode *inode); 120 extern int isofs_name_translate(struct iso_directory_record *, char *, struct inode *); 121 bool isofs_dir_record_valid(struct iso_directory_record *de, 122 unsigned long offset, 123 unsigned long bufsize); 124 125 /* 126 * The longest name the Joliet converter returns, in bytes. A directory 127 * record is at most 255 bytes long, which leaves room for 111 UTF-16 units 128 * of name, and no character set needs more than three bytes for one unit. 129 */ 130 #define JOLIET_NAME_MAX \ 131 ((255 - sizeof(struct iso_directory_record)) / 2 * 3) 132 133 int get_joliet_filename(struct iso_directory_record *de, unsigned char *outname, 134 int outsize, struct inode *inode); 135 int get_acorn_filename(struct iso_directory_record *, char *, struct inode *); 136 137 extern struct dentry *isofs_lookup(struct inode *, struct dentry *, unsigned int flags); 138 extern struct buffer_head *isofs_bread(struct inode *, sector_t); 139 extern int isofs_get_blocks(struct inode *, sector_t, struct buffer_head **, unsigned long); 140 141 struct inode *__isofs_iget(struct super_block *sb, 142 unsigned long block, 143 unsigned long offset, 144 int relocated); 145 146 static inline struct inode *isofs_iget(struct super_block *sb, 147 unsigned long block, 148 unsigned long offset) 149 { 150 return __isofs_iget(sb, block, offset, 0); 151 } 152 153 static inline struct inode *isofs_iget_reloc(struct super_block *sb, 154 unsigned long block, 155 unsigned long offset) 156 { 157 return __isofs_iget(sb, block, offset, 1); 158 } 159 160 /* Because the inode number is no longer relevant to finding the 161 * underlying meta-data for an inode, we are free to choose a more 162 * convenient 32-bit number as the inode number. The inode numbering 163 * scheme was recommended by Sergey Vlasov and Eric Lammerts. */ 164 static inline unsigned long isofs_get_ino(unsigned long block, 165 unsigned long offset, 166 unsigned long bufbits) 167 { 168 return (block << (bufbits - 5)) | (offset >> 5); 169 } 170 171 /* Every directory can have many redundant directory entries scattered 172 * throughout the directory tree. First there is the directory entry 173 * with the name of the directory stored in the parent directory. 174 * Then, there is the "." directory entry stored in the directory 175 * itself. Finally, there are possibly many ".." directory entries 176 * stored in all the subdirectories. 177 * 178 * In order for the NFS get_parent() method to work and for the 179 * general consistency of the dcache, we need to make sure the 180 * "i_iget5_block" and "i_iget5_offset" all point to exactly one of 181 * the many redundant entries for each directory. We normalize the 182 * block and offset by always making them point to the "." directory. 183 * 184 * Notice that we do not use the entry for the directory with the name 185 * that is located in the parent directory. Even though choosing this 186 * first directory is more natural, it is much easier to find the "." 187 * entry in the NFS get_parent() method because it is implicitly 188 * encoded in the "extent + ext_attr_length" fields of _all_ the 189 * redundant entries for the directory. Thus, it can always be 190 * reached regardless of which directory entry you have in hand. 191 * 192 * This works because the "." entry is simply the first directory 193 * record when you start reading the file that holds all the directory 194 * records, and this file starts at "extent + ext_attr_length" blocks. 195 * Because the "." entry is always the first entry listed in the 196 * directories file, the normalized "offset" value is always 0. 197 * 198 * You should pass the directory entry in "de". On return, "block" 199 * and "offset" will hold normalized values. Only directories are 200 * affected making it safe to call even for non-directory file 201 * types. */ 202 static inline void 203 isofs_normalize_block_and_offset(struct iso_directory_record* de, 204 unsigned long *block, 205 unsigned long *offset) 206 { 207 /* Only directories are normalized. */ 208 if (de->flags[0] & 2) { 209 *offset = 0; 210 *block = (unsigned long)isonum_733(de->extent) 211 + (unsigned long)isonum_711(de->ext_attr_length); 212 } 213 } 214 215 struct file_kattr; 216 int isofs_fileattr_get(struct dentry *dentry, struct file_kattr *fa); 217 218 extern const struct inode_operations isofs_dir_inode_operations; 219 extern const struct file_operations isofs_dir_operations; 220 extern const struct address_space_operations isofs_symlink_aops; 221 extern const struct export_operations isofs_export_ops; 222