fs/hfsplus/ioctl.c

   1 /*
   2  *  linux/fs/hfsplus/ioctl.c
   3  *
   4  * Copyright (C) 2003
   5  * Ethan Benson <erbenson@alaska.net>
   6  * partially derived from linux/fs/ext2/ioctl.c
   7  * Copyright (C) 1993, 1994, 1995
   8  * Remy Card (card@masi.ibp.fr)
   9  * Laboratoire MASI - Institut Blaise Pascal
  10  * Universite Pierre et Marie Curie (Paris VI)
  11  *
  12  * hfsplus ioctls
  13  */
  14
  15 #include <linux/capability.h>
  16 #include <linux/fs.h>
  17 #include <linux/mount.h>
  18 #include <linux/sched.h>
  19 #include <linux/xattr.h>
  20 #include <asm/uaccess.h>
  21 #include "hfsplus_fs.h"
  22
  23 /*
  24  * "Blessing" an HFS+ filesystem writes metadata to the superblock informing
  25  * the platform firmware which file to boot from
  26  */
  27 static int hfsplus_ioctl_bless(struct file *file, int __user *user_flags)
  28 {
  29         struct dentry *dentry = file->f_path.dentry;
  30         struct inode *inode = dentry->d_inode;
  31         struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
  32         struct hfsplus_vh *vh = sbi->s_vhdr;
  33         struct hfsplus_vh *bvh = sbi->s_backup_vhdr;
  34         u32 cnid = (unsigned long)dentry->d_fsdata;
  35
  36         if (!capable(CAP_SYS_ADMIN))
  37                 return -EPERM;
  38
  39         mutex_lock(&sbi->vh_mutex);
  40
  41         /* Directory containing the bootable system */
  42         vh->finder_info[0] = bvh->finder_info[0] =
  43                 cpu_to_be32(parent_ino(dentry));
  44
  45         /*
  46          * Bootloader. Just using the inode here breaks in the case of
  47          * hard links - the firmware wants the ID of the hard link file,
  48          * but the inode points at the indirect inode
  49          */
  50         vh->finder_info[1] = bvh->finder_info[1] = cpu_to_be32(cnid);
  51
  52         /* Per spec, the OS X system folder - same as finder_info[0] here */
  53         vh->finder_info[5] = bvh->finder_info[5] =
  54                 cpu_to_be32(parent_ino(dentry));
  55
  56         mutex_unlock(&sbi->vh_mutex);
  57         return 0;
  58 }
  59
  60 static int hfsplus_ioctl_getflags(struct file *file, int __user *user_flags)
  61 {
  62         struct inode *inode = file->f_path.dentry->d_inode;
  63         struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
  64         unsigned int flags = 0;
  65
  66         if (inode->i_flags & S_IMMUTABLE)
  67                 flags |= FS_IMMUTABLE_FL;
  68         if (inode->i_flags & S_APPEND)
  69                 flags |= FS_APPEND_FL;
  70         if (hip->userflags & HFSPLUS_FLG_NODUMP)
  71                 flags |= FS_NODUMP_FL;
  72
  73         return put_user(flags, user_flags);
  74 }
  75
  76 static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
  77 {
  78         struct inode *inode = file->f_path.dentry->d_inode;
  79         struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
  80         unsigned int flags;
  81         int err = 0;
  82
  83         err = mnt_want_write_file(file);
  84         if (err)
  85                 goto out;
  86
  87         if (!inode_owner_or_capable(inode)) {
  88                 err = -EACCES;
  89                 goto out_drop_write;
  90         }
  91
  92         if (get_user(flags, user_flags)) {
  93                 err = -EFAULT;
  94                 goto out_drop_write;
  95         }
  96
  97         mutex_lock(&inode->i_mutex);
  98
  99         if ((flags & (FS_IMMUTABLE_FL|FS_APPEND_FL)) ||
 100             inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
 101                 if (!capable(CAP_LINUX_IMMUTABLE)) {
 102                         err = -EPERM;
 103                         goto out_unlock_inode;
 104                 }
 105         }
 106
 107         /* don't silently ignore unsupported ext2 flags */
 108         if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
 109                 err = -EOPNOTSUPP;
 110                 goto out_unlock_inode;
 111         }
 112
 113         if (flags & FS_IMMUTABLE_FL)
 114                 inode->i_flags |= S_IMMUTABLE;
 115         else
 116                 inode->i_flags &= ~S_IMMUTABLE;
 117
 118         if (flags & FS_APPEND_FL)
 119                 inode->i_flags |= S_APPEND;
 120         else
 121                 inode->i_flags &= ~S_APPEND;
 122
 123         if (flags & FS_NODUMP_FL)
 124                 hip->userflags |= HFSPLUS_FLG_NODUMP;
 125         else
 126                 hip->userflags &= ~HFSPLUS_FLG_NODUMP;
 127
 128         inode->i_ctime = CURRENT_TIME_SEC;
 129         mark_inode_dirty(inode);
 130
 131 out_unlock_inode:
 132         mutex_unlock(&inode->i_mutex);
 133 out_drop_write:
 134         mnt_drop_write_file(file);
 135 out:
 136         return err;
 137 }
 138
 139 long hfsplus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 140 {
 141         void __user *argp = (void __user *)arg;
 142
 143         switch (cmd) {
 144         case HFSPLUS_IOC_EXT2_GETFLAGS:
 145                 return hfsplus_ioctl_getflags(file, argp);
 146         case HFSPLUS_IOC_EXT2_SETFLAGS:
 147                 return hfsplus_ioctl_setflags(file, argp);
 148         case HFSPLUS_IOC_BLESS:
 149                 return hfsplus_ioctl_bless(file, argp);
 150         default:
 151                 return -ENOTTY;
 152         }
 153 }
 154
 155 int hfsplus_setxattr(struct dentry *dentry, const char *name,
 156                      const void *value, size_t size, int flags)
 157 {
 158         struct inode *inode = dentry->d_inode;
 159         struct hfs_find_data fd;
 160         hfsplus_cat_entry entry;
 161         struct hfsplus_cat_file *file;
 162         int res;
 163
 164         if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
 165                 return -EOPNOTSUPP;
 166
 167         res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
 168         if (res)
 169                 return res;
 170         res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
 171         if (res)
 172                 goto out;
 173         hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 174                         sizeof(struct hfsplus_cat_file));
 175         file = &entry.file;
 176
 177         if (!strcmp(name, "hfs.type")) {
 178                 if (size == 4)
 179                         memcpy(&file->user_info.fdType, value, 4);
 180                 else
 181                         res = -ERANGE;
 182         } else if (!strcmp(name, "hfs.creator")) {
 183                 if (size == 4)
 184                         memcpy(&file->user_info.fdCreator, value, 4);
 185                 else
 186                         res = -ERANGE;
 187         } else
 188                 res = -EOPNOTSUPP;
 189         if (!res) {
 190                 hfs_bnode_write(fd.bnode, &entry, fd.entryoffset,
 191                                 sizeof(struct hfsplus_cat_file));
 192                 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 193         }
 194 out:
 195         hfs_find_exit(&fd);
 196         return res;
 197 }
 198
 199 ssize_t hfsplus_getxattr(struct dentry *dentry, const char *name,
 200                          void *value, size_t size)
 201 {
 202         struct inode *inode = dentry->d_inode;
 203         struct hfs_find_data fd;
 204         hfsplus_cat_entry entry;
 205         struct hfsplus_cat_file *file;
 206         ssize_t res = 0;
 207
 208         if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
 209                 return -EOPNOTSUPP;
 210
 211         if (size) {
 212                 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
 213                 if (res)
 214                         return res;
 215                 res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
 216                 if (res)
 217                         goto out;
 218                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 219                                 sizeof(struct hfsplus_cat_file));
 220         }
 221         file = &entry.file;
 222
 223         if (!strcmp(name, "hfs.type")) {
 224                 if (size >= 4) {
 225                         memcpy(value, &file->user_info.fdType, 4);
 226                         res = 4;
 227                 } else
 228                         res = size ? -ERANGE : 4;
 229         } else if (!strcmp(name, "hfs.creator")) {
 230                 if (size >= 4) {
 231                         memcpy(value, &file->user_info.fdCreator, 4);
 232                         res = 4;
 233                 } else
 234                         res = size ? -ERANGE : 4;
 235         } else
 236                 res = -EOPNOTSUPP;
 237 out:
 238         if (size)
 239                 hfs_find_exit(&fd);
 240         return res;
 241 }
 242
 243 #define HFSPLUS_ATTRLIST_SIZE (sizeof("hfs.creator")+sizeof("hfs.type"))
 244
 245 ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
 246 {
 247         struct inode *inode = dentry->d_inode;
 248
 249         if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
 250                 return -EOPNOTSUPP;
 251
 252         if (!buffer || !size)
 253                 return HFSPLUS_ATTRLIST_SIZE;
 254         if (size < HFSPLUS_ATTRLIST_SIZE)
 255                 return -ERANGE;
 256         strcpy(buffer, "hfs.type");
 257         strcpy(buffer + sizeof("hfs.type"), "hfs.creator");
 258
 259         return HFSPLUS_ATTRLIST_SIZE;
 260 }