summaryrefslogtreecommitdiff
path: root/fs/hfsplus/ioctl.c
blob: 0a156d84e67d63aaa75f57bd3741b59e4bf47748 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
/*
 *  linux/fs/hfsplus/ioctl.c
 *
 * Copyright (C) 2003
 * Ethan Benson <erbenson@alaska.net>
 * partially derived from linux/fs/ext2/ioctl.c
 * Copyright (C) 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 * hfsplus ioctls
 */

#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include "hfsplus_fs.h"

/*
 * "Blessing" an HFS+ filesystem writes metadata to the superblock informing
 * the platform firmware which file to boot from
 */
static int hfsplus_ioctl_bless(struct file *file, int __user *user_flags)
{
	struct dentry *dentry = file->f_path.dentry;
	struct inode *inode = d_inode(dentry);
	struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
	struct hfsplus_vh *vh = sbi->s_vhdr;
	struct hfsplus_vh *bvh = sbi->s_backup_vhdr;
	u32 cnid = (unsigned long)dentry->d_fsdata;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	mutex_lock(&sbi->vh_mutex);

	/* Directory containing the bootable system */
	vh->finder_info[0] = bvh->finder_info[0] =
		cpu_to_be32(parent_ino(dentry));

	/*
	 * Bootloader. Just using the inode here breaks in the case of
	 * hard links - the firmware wants the ID of the hard link file,
	 * but the inode points at the indirect inode
	 */
	vh->finder_info[1] = bvh->finder_info[1] = cpu_to_be32(cnid);

	/* Per spec, the OS X system folder - same as finder_info[0] here */
	vh->finder_info[5] = bvh->finder_info[5] =
		cpu_to_be32(parent_ino(dentry));

	mutex_unlock(&sbi->vh_mutex);
	return 0;
}

static int hfsplus_ioctl_getflags(struct file *file, int __user *user_flags)
{
	struct inode *inode = file_inode(file);
	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
	unsigned int flags = 0;

	if (inode->i_flags & S_IMMUTABLE)
		flags |= FS_IMMUTABLE_FL;
	if (inode->i_flags & S_APPEND)
		flags |= FS_APPEND_FL;
	if (hip->userflags & HFSPLUS_FLG_NODUMP)
		flags |= FS_NODUMP_FL;

	return put_user(flags, user_flags);
}

static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
{
	struct inode *inode = file_inode(file);
	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
	unsigned int flags, new_fl = 0;
	int err = 0;

	err = mnt_want_write_file(file);
	if (err)
		goto out;

	if (!inode_owner_or_capable(inode)) {
		err = -EACCES;
		goto out_drop_write;
	}

	if (get_user(flags, user_flags)) {
		err = -EFAULT;
		goto out_drop_write;
	}

	inode_lock(inode);

	if ((flags & (FS_IMMUTABLE_FL|FS_APPEND_FL)) ||
	    inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
		if (!capable(CAP_LINUX_IMMUTABLE)) {
			err = -EPERM;
			goto out_unlock_inode;
		}
	}

	/* don't silently ignore unsupported ext2 flags */
	if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
		err = -EOPNOTSUPP;
		goto out_unlock_inode;
	}

	if (flags & FS_IMMUTABLE_FL)
		new_fl |= S_IMMUTABLE;

	if (flags & FS_APPEND_FL)
		new_fl |= S_APPEND;

	inode_set_flags(inode, new_fl, S_IMMUTABLE | S_APPEND);

	if (flags & FS_NODUMP_FL)
		hip->userflags |= HFSPLUS_FLG_NODUMP;
	else
		hip->userflags &= ~HFSPLUS_FLG_NODUMP;

	inode->i_ctime = current_time(inode);
	mark_inode_dirty(inode);

out_unlock_inode:
	inode_unlock(inode);
out_drop_write:
	mnt_drop_write_file(file);
out:
	return err;
}

long hfsplus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;

	switch (cmd) {
	case HFSPLUS_IOC_EXT2_GETFLAGS:
		return hfsplus_ioctl_getflags(file, argp);
	case HFSPLUS_IOC_EXT2_SETFLAGS:
		return hfsplus_ioctl_setflags(file, argp);
	case HFSPLUS_IOC_BLESS:
		return hfsplus_ioctl_bless(file, argp);
	default:
		return -ENOTTY;
	}
}