xref: /openbmc/linux/fs/hfsplus/ioctl.c (revision 63dc02bd)
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 
35 	if (!capable(CAP_SYS_ADMIN))
36 		return -EPERM;
37 
38 	mutex_lock(&sbi->vh_mutex);
39 
40 	/* Directory containing the bootable system */
41 	vh->finder_info[0] = bvh->finder_info[0] =
42 		cpu_to_be32(parent_ino(dentry));
43 
44 	/* Bootloader */
45 	vh->finder_info[1] = bvh->finder_info[1] = cpu_to_be32(inode->i_ino);
46 
47 	/* Per spec, the OS X system folder - same as finder_info[0] here */
48 	vh->finder_info[5] = bvh->finder_info[5] =
49 		cpu_to_be32(parent_ino(dentry));
50 
51 	mutex_unlock(&sbi->vh_mutex);
52 	return 0;
53 }
54 
55 static int hfsplus_ioctl_getflags(struct file *file, int __user *user_flags)
56 {
57 	struct inode *inode = file->f_path.dentry->d_inode;
58 	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
59 	unsigned int flags = 0;
60 
61 	if (inode->i_flags & S_IMMUTABLE)
62 		flags |= FS_IMMUTABLE_FL;
63 	if (inode->i_flags & S_APPEND)
64 		flags |= FS_APPEND_FL;
65 	if (hip->userflags & HFSPLUS_FLG_NODUMP)
66 		flags |= FS_NODUMP_FL;
67 
68 	return put_user(flags, user_flags);
69 }
70 
71 static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
72 {
73 	struct inode *inode = file->f_path.dentry->d_inode;
74 	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
75 	unsigned int flags;
76 	int err = 0;
77 
78 	err = mnt_want_write_file(file);
79 	if (err)
80 		goto out;
81 
82 	if (!inode_owner_or_capable(inode)) {
83 		err = -EACCES;
84 		goto out_drop_write;
85 	}
86 
87 	if (get_user(flags, user_flags)) {
88 		err = -EFAULT;
89 		goto out_drop_write;
90 	}
91 
92 	mutex_lock(&inode->i_mutex);
93 
94 	if ((flags & (FS_IMMUTABLE_FL|FS_APPEND_FL)) ||
95 	    inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
96 		if (!capable(CAP_LINUX_IMMUTABLE)) {
97 			err = -EPERM;
98 			goto out_unlock_inode;
99 		}
100 	}
101 
102 	/* don't silently ignore unsupported ext2 flags */
103 	if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
104 		err = -EOPNOTSUPP;
105 		goto out_unlock_inode;
106 	}
107 
108 	if (flags & FS_IMMUTABLE_FL)
109 		inode->i_flags |= S_IMMUTABLE;
110 	else
111 		inode->i_flags &= ~S_IMMUTABLE;
112 
113 	if (flags & FS_APPEND_FL)
114 		inode->i_flags |= S_APPEND;
115 	else
116 		inode->i_flags &= ~S_APPEND;
117 
118 	if (flags & FS_NODUMP_FL)
119 		hip->userflags |= HFSPLUS_FLG_NODUMP;
120 	else
121 		hip->userflags &= ~HFSPLUS_FLG_NODUMP;
122 
123 	inode->i_ctime = CURRENT_TIME_SEC;
124 	mark_inode_dirty(inode);
125 
126 out_unlock_inode:
127 	mutex_unlock(&inode->i_mutex);
128 out_drop_write:
129 	mnt_drop_write_file(file);
130 out:
131 	return err;
132 }
133 
134 long hfsplus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
135 {
136 	void __user *argp = (void __user *)arg;
137 
138 	switch (cmd) {
139 	case HFSPLUS_IOC_EXT2_GETFLAGS:
140 		return hfsplus_ioctl_getflags(file, argp);
141 	case HFSPLUS_IOC_EXT2_SETFLAGS:
142 		return hfsplus_ioctl_setflags(file, argp);
143 	case HFSPLUS_IOC_BLESS:
144 		return hfsplus_ioctl_bless(file, argp);
145 	default:
146 		return -ENOTTY;
147 	}
148 }
149 
150 int hfsplus_setxattr(struct dentry *dentry, const char *name,
151 		     const void *value, size_t size, int flags)
152 {
153 	struct inode *inode = dentry->d_inode;
154 	struct hfs_find_data fd;
155 	hfsplus_cat_entry entry;
156 	struct hfsplus_cat_file *file;
157 	int res;
158 
159 	if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
160 		return -EOPNOTSUPP;
161 
162 	res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
163 	if (res)
164 		return res;
165 	res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
166 	if (res)
167 		goto out;
168 	hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
169 			sizeof(struct hfsplus_cat_file));
170 	file = &entry.file;
171 
172 	if (!strcmp(name, "hfs.type")) {
173 		if (size == 4)
174 			memcpy(&file->user_info.fdType, value, 4);
175 		else
176 			res = -ERANGE;
177 	} else if (!strcmp(name, "hfs.creator")) {
178 		if (size == 4)
179 			memcpy(&file->user_info.fdCreator, value, 4);
180 		else
181 			res = -ERANGE;
182 	} else
183 		res = -EOPNOTSUPP;
184 	if (!res) {
185 		hfs_bnode_write(fd.bnode, &entry, fd.entryoffset,
186 				sizeof(struct hfsplus_cat_file));
187 		hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
188 	}
189 out:
190 	hfs_find_exit(&fd);
191 	return res;
192 }
193 
194 ssize_t hfsplus_getxattr(struct dentry *dentry, const char *name,
195 			 void *value, size_t size)
196 {
197 	struct inode *inode = dentry->d_inode;
198 	struct hfs_find_data fd;
199 	hfsplus_cat_entry entry;
200 	struct hfsplus_cat_file *file;
201 	ssize_t res = 0;
202 
203 	if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
204 		return -EOPNOTSUPP;
205 
206 	if (size) {
207 		res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
208 		if (res)
209 			return res;
210 		res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
211 		if (res)
212 			goto out;
213 		hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
214 				sizeof(struct hfsplus_cat_file));
215 	}
216 	file = &entry.file;
217 
218 	if (!strcmp(name, "hfs.type")) {
219 		if (size >= 4) {
220 			memcpy(value, &file->user_info.fdType, 4);
221 			res = 4;
222 		} else
223 			res = size ? -ERANGE : 4;
224 	} else if (!strcmp(name, "hfs.creator")) {
225 		if (size >= 4) {
226 			memcpy(value, &file->user_info.fdCreator, 4);
227 			res = 4;
228 		} else
229 			res = size ? -ERANGE : 4;
230 	} else
231 		res = -EOPNOTSUPP;
232 out:
233 	if (size)
234 		hfs_find_exit(&fd);
235 	return res;
236 }
237 
238 #define HFSPLUS_ATTRLIST_SIZE (sizeof("hfs.creator")+sizeof("hfs.type"))
239 
240 ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
241 {
242 	struct inode *inode = dentry->d_inode;
243 
244 	if (!S_ISREG(inode->i_mode) || HFSPLUS_IS_RSRC(inode))
245 		return -EOPNOTSUPP;
246 
247 	if (!buffer || !size)
248 		return HFSPLUS_ATTRLIST_SIZE;
249 	if (size < HFSPLUS_ATTRLIST_SIZE)
250 		return -ERANGE;
251 	strcpy(buffer, "hfs.type");
252 	strcpy(buffer + sizeof("hfs.type"), "hfs.creator");
253 
254 	return HFSPLUS_ATTRLIST_SIZE;
255 }
256