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 */
 27static 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
 60static 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
 76static 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
131out_unlock_inode:
132	mutex_unlock(&inode->i_mutex);
133out_drop_write:
134	mnt_drop_write_file(file);
135out:
136	return err;
137}
138
139long 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
155int 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	}
194out:
195	hfs_find_exit(&fd);
196	return res;
197}
198
199ssize_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;
237out:
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
245ssize_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}