[deliverable/linux.git] / fs / ecryptfs / file.c

/**
 * eCryptfs: Linux filesystem encryption layer
 *
 * Copyright (C) 1997-2004 Erez Zadok
 * Copyright (C) 2001-2004 Stony Brook University
 * Copyright (C) 2004-2007 International Business Machines Corp.
 *   Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
 *   		Michael C. Thompson <mcthomps@us.ibm.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 */

#include <linux/file.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/mount.h>
#include <linux/pagemap.h>
#include <linux/security.h>
#include <linux/compat.h>
#include <linux/fs_stack.h>
#include "ecryptfs_kernel.h"

/**
 * ecryptfs_read_update_atime
 *
 * generic_file_read updates the atime of upper layer inode.  But, it
 * doesn't give us a chance to update the atime of the lower layer
 * inode.  This function is a wrapper to generic_file_read.  It
 * updates the atime of the lower level inode if generic_file_read
 * returns without any errors. This is to be used only for file reads.
 * The function to be used for directory reads is ecryptfs_read.
 */
static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
				struct iov_iter *to)
{
	ssize_t rc;
	struct path *path;
	struct file *file = iocb->ki_filp;

	rc = generic_file_read_iter(iocb, to);
	if (rc >= 0) {
		path = ecryptfs_dentry_to_lower_path(file->f_path.dentry);
		touch_atime(path);
	}
	return rc;
}

struct ecryptfs_getdents_callback {
	struct dir_context ctx;
	struct dir_context *caller;
	struct super_block *sb;
	int filldir_called;
	int entries_written;
};

/* Inspired by generic filldir in fs/readdir.c */
static int
ecryptfs_filldir(struct dir_context *ctx, const char *lower_name,
		 int lower_namelen, loff_t offset, u64 ino, unsigned int d_type)
{
	struct ecryptfs_getdents_callback *buf =
		container_of(ctx, struct ecryptfs_getdents_callback, ctx);
	size_t name_size;
	char *name;
	int rc;

	buf->filldir_called++;
	rc = ecryptfs_decode_and_decrypt_filename(&name, &name_size,
						  buf->sb, lower_name,
						  lower_namelen);
	if (rc) {
		printk(KERN_ERR "%s: Error attempting to decode and decrypt "
		       "filename [%s]; rc = [%d]\n", __func__, lower_name,
		       rc);
		goto out;
	}
	buf->caller->pos = buf->ctx.pos;
	rc = !dir_emit(buf->caller, name, name_size, ino, d_type);
	kfree(name);
	if (!rc)
		buf->entries_written++;
out:
	return rc;
}

/**
 * ecryptfs_readdir
 * @file: The eCryptfs directory file
 * @ctx: The actor to feed the entries to
 */
static int ecryptfs_readdir(struct file *file, struct dir_context *ctx)
{
	int rc;
	struct file *lower_file;
	struct inode *inode = file_inode(file);
	struct ecryptfs_getdents_callback buf = {
		.ctx.actor = ecryptfs_filldir,
		.caller = ctx,
		.sb = inode->i_sb,
	};
	lower_file = ecryptfs_file_to_lower(file);
	rc = iterate_dir(lower_file, &buf.ctx);
	ctx->pos = buf.ctx.pos;
	if (rc < 0)
		goto out;
	if (buf.filldir_called && !buf.entries_written)
		goto out;
	if (rc >= 0)
		fsstack_copy_attr_atime(inode,
					file_inode(lower_file));
out:
	return rc;
}

struct kmem_cache *ecryptfs_file_info_cache;

static int read_or_initialize_metadata(struct dentry *dentry)
{
	struct inode *inode = d_inode(dentry);
	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
	struct ecryptfs_crypt_stat *crypt_stat;
	int rc;

	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
	mount_crypt_stat = &ecryptfs_superblock_to_private(
						inode->i_sb)->mount_crypt_stat;
	mutex_lock(&crypt_stat->cs_mutex);

	if (crypt_stat->flags & ECRYPTFS_POLICY_APPLIED &&
	    crypt_stat->flags & ECRYPTFS_KEY_VALID) {
		rc = 0;
		goto out;
	}

	rc = ecryptfs_read_metadata(dentry);
	if (!rc)
		goto out;

	if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED) {
		crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
				       | ECRYPTFS_ENCRYPTED);
		rc = 0;
		goto out;
	}

	if (!(mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED) &&
	    !i_size_read(ecryptfs_inode_to_lower(inode))) {
		rc = ecryptfs_initialize_file(dentry, inode);
		if (!rc)
			goto out;
	}

	rc = -EIO;
out:
	mutex_unlock(&crypt_stat->cs_mutex);
	return rc;
}

/**
 * ecryptfs_open
 * @inode: inode speciying file to open
 * @file: Structure to return filled in
 *
 * Opens the file specified by inode.
 *
 * Returns zero on success; non-zero otherwise
 */
static int ecryptfs_open(struct inode *inode, struct file *file)
{
	int rc = 0;
	struct ecryptfs_crypt_stat *crypt_stat = NULL;
	struct dentry *ecryptfs_dentry = file->f_path.dentry;
	/* Private value of ecryptfs_dentry allocated in
	 * ecryptfs_lookup() */
	struct ecryptfs_file_info *file_info;

	/* Released in ecryptfs_release or end of function if failure */
	file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
	ecryptfs_set_file_private(file, file_info);
	if (!file_info) {
		ecryptfs_printk(KERN_ERR,
				"Error attempting to allocate memory\n");
		rc = -ENOMEM;
		goto out;
	}
	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
	mutex_lock(&crypt_stat->cs_mutex);
	if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
		ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
		/* Policy code enabled in future release */
		crypt_stat->flags |= (ECRYPTFS_POLICY_APPLIED
				      | ECRYPTFS_ENCRYPTED);
	}
	mutex_unlock(&crypt_stat->cs_mutex);
	rc = ecryptfs_get_lower_file(ecryptfs_dentry, inode);
	if (rc) {
		printk(KERN_ERR "%s: Error attempting to initialize "
			"the lower file for the dentry with name "
			"[%pd]; rc = [%d]\n", __func__,
			ecryptfs_dentry, rc);
		goto out_free;
	}
	if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
	    == O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
		rc = -EPERM;
		printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
		       "file must hence be opened RO\n", __func__);
		goto out_put;
	}
	ecryptfs_set_file_lower(
		file, ecryptfs_inode_to_private(inode)->lower_file);
	rc = read_or_initialize_metadata(ecryptfs_dentry);
	if (rc)
		goto out_put;
	ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = "
			"[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
			(unsigned long long)i_size_read(inode));
	goto out;
out_put:
	ecryptfs_put_lower_file(inode);
out_free:
	kmem_cache_free(ecryptfs_file_info_cache,
			ecryptfs_file_to_private(file));
out:
	return rc;
}

/**
 * ecryptfs_dir_open
 * @inode: inode speciying file to open
 * @file: Structure to return filled in
 *
 * Opens the file specified by inode.
 *
 * Returns zero on success; non-zero otherwise
 */
static int ecryptfs_dir_open(struct inode *inode, struct file *file)
{
	struct dentry *ecryptfs_dentry = file->f_path.dentry;
	/* Private value of ecryptfs_dentry allocated in
	 * ecryptfs_lookup() */
	struct ecryptfs_file_info *file_info;
	struct file *lower_file;

	/* Released in ecryptfs_release or end of function if failure */
	file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
	ecryptfs_set_file_private(file, file_info);
	if (unlikely(!file_info)) {
		ecryptfs_printk(KERN_ERR,
				"Error attempting to allocate memory\n");
		return -ENOMEM;
	}
	lower_file = dentry_open(ecryptfs_dentry_to_lower_path(ecryptfs_dentry),
				 file->f_flags, current_cred());
	if (IS_ERR(lower_file)) {
		printk(KERN_ERR "%s: Error attempting to initialize "
			"the lower file for the dentry with name "
			"[%pd]; rc = [%ld]\n", __func__,
			ecryptfs_dentry, PTR_ERR(lower_file));
		kmem_cache_free(ecryptfs_file_info_cache, file_info);
		return PTR_ERR(lower_file);
	}
	ecryptfs_set_file_lower(file, lower_file);
	return 0;
}

static int ecryptfs_flush(struct file *file, fl_owner_t td)
{
	struct file *lower_file = ecryptfs_file_to_lower(file);

	if (lower_file->f_op->flush) {
		filemap_write_and_wait(file->f_mapping);
		return lower_file->f_op->flush(lower_file, td);
	}

	return 0;
}

static int ecryptfs_release(struct inode *inode, struct file *file)
{
	ecryptfs_put_lower_file(inode);
	kmem_cache_free(ecryptfs_file_info_cache,
			ecryptfs_file_to_private(file));
	return 0;
}

static int ecryptfs_dir_release(struct inode *inode, struct file *file)
{
	fput(ecryptfs_file_to_lower(file));
	kmem_cache_free(ecryptfs_file_info_cache,
			ecryptfs_file_to_private(file));
	return 0;
}

static loff_t ecryptfs_dir_llseek(struct file *file, loff_t offset, int whence)
{
	return vfs_llseek(ecryptfs_file_to_lower(file), offset, whence);
}

static int
ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
	int rc;

	rc = filemap_write_and_wait(file->f_mapping);
	if (rc)
		return rc;

	return vfs_fsync(ecryptfs_file_to_lower(file), datasync);
}

static int ecryptfs_fasync(int fd, struct file *file, int flag)
{
	int rc = 0;
	struct file *lower_file = NULL;

	lower_file = ecryptfs_file_to_lower(file);
	if (lower_file->f_op->fasync)
		rc = lower_file->f_op->fasync(fd, lower_file, flag);
	return rc;
}

static long
ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	struct file *lower_file = ecryptfs_file_to_lower(file);
	long rc = -ENOTTY;

	if (!lower_file->f_op->unlocked_ioctl)
		return rc;

	switch (cmd) {
	case FITRIM:
	case FS_IOC_GETFLAGS:
	case FS_IOC_SETFLAGS:
	case FS_IOC_GETVERSION:
	case FS_IOC_SETVERSION:
		rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
		fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));

		return rc;
	default:
		return rc;
	}
}

#ifdef CONFIG_COMPAT
static long
ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	struct file *lower_file = ecryptfs_file_to_lower(file);
	long rc = -ENOIOCTLCMD;

	if (!lower_file->f_op->compat_ioctl)
		return rc;

	switch (cmd) {
	case FS_IOC32_GETFLAGS:
	case FS_IOC32_SETFLAGS:
	case FS_IOC32_GETVERSION:
	case FS_IOC32_SETVERSION:
		rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
		fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));

		return rc;
	default:
		return rc;
	}
}
#endif

const struct file_operations ecryptfs_dir_fops = {
	.iterate_shared = ecryptfs_readdir,
	.read = generic_read_dir,
	.unlocked_ioctl = ecryptfs_unlocked_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = ecryptfs_compat_ioctl,
#endif
	.open = ecryptfs_dir_open,
	.release = ecryptfs_dir_release,
	.fsync = ecryptfs_fsync,
	.llseek = ecryptfs_dir_llseek,
};

const struct file_operations ecryptfs_main_fops = {
	.llseek = generic_file_llseek,
	.read_iter = ecryptfs_read_update_atime,
	.write_iter = generic_file_write_iter,
	.unlocked_ioctl = ecryptfs_unlocked_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = ecryptfs_compat_ioctl,
#endif
	.mmap = generic_file_mmap,
	.open = ecryptfs_open,
	.flush = ecryptfs_flush,
	.release = ecryptfs_release,
	.fsync = ecryptfs_fsync,
	.fasync = ecryptfs_fasync,
	.splice_read = generic_file_splice_read,
};
Commit	Line	Data
237fead6 MH	1	/**
	2	* eCryptfs: Linux filesystem encryption layer
	3	*
	4	* Copyright (C) 1997-2004 Erez Zadok
	5	* Copyright (C) 2001-2004 Stony Brook University
dd2a3b7a	6	* Copyright (C) 2004-2007 International Business Machines Corp.
237fead6 MH	7	* Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
	8	* Michael C. Thompson <mcthomps@us.ibm.com>
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public License as
	12	* published by the Free Software Foundation; either version 2 of the
	13	* License, or (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful, but
	16	* WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to the Free Software
	22	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
	23	* 02111-1307, USA.
	24	*/
	25
	26	#include <linux/file.h>
	27	#include <linux/poll.h>
5a0e3ad6	28	#include <linux/slab.h>
237fead6 MH	29	#include <linux/mount.h>
	30	#include <linux/pagemap.h>
	31	#include <linux/security.h>
237fead6	32	#include <linux/compat.h>
0cc72dc7	33	#include <linux/fs_stack.h>
237fead6 MH	34	#include "ecryptfs_kernel.h"
237fead6 MH	35
237fead6 MH	36	/**
	37	* ecryptfs_read_update_atime
	38	*
	39	* generic_file_read updates the atime of upper layer inode. But, it
	40	* doesn't give us a chance to update the atime of the lower layer
	41	* inode. This function is a wrapper to generic_file_read. It
	42	* updates the atime of the lower level inode if generic_file_read
	43	* returns without any errors. This is to be used only for file reads.
	44	* The function to be used for directory reads is ecryptfs_read.
	45	*/
	46	static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
02797829	47	struct iov_iter *to)
237fead6	48	{
38a708d7	49	ssize_t rc;
cc18ec3c	50	struct path *path;
237fead6 MH	51	struct file *file = iocb->ki_filp;
237fead6 MH	52
02797829	53	rc = generic_file_read_iter(iocb, to);
237fead6	54	if (rc >= 0) {
cc18ec3c MW	55	path = ecryptfs_dentry_to_lower_path(file->f_path.dentry);
cc18ec3c MW	56	touch_atime(path);
237fead6 MH	57	}
	58	return rc;
	59	}
	60
	61	struct ecryptfs_getdents_callback {
5c0ba4e0	62	struct dir_context ctx;
2de5f059	63	struct dir_context *caller;
0747fdb2	64	struct super_block *sb;
237fead6 MH	65	int filldir_called;
	66	int entries_written;
	67	};
	68
7d6c7045	69	/* Inspired by generic filldir in fs/readdir.c */
237fead6	70	static int
ac7576f4 MS	71	ecryptfs_filldir(struct dir_context ctx, const char lower_name,
ac7576f4 MS	72	int lower_namelen, loff_t offset, u64 ino, unsigned int d_type)
237fead6	73	{
237fead6	74	struct ecryptfs_getdents_callback *buf =
ac7576f4	75	container_of(ctx, struct ecryptfs_getdents_callback, ctx);
a8f12864	76	size_t name_size;
addd65ad	77	char *name;
237fead6	78	int rc;
237fead6	79
237fead6	80	buf->filldir_called++;
addd65ad	81	rc = ecryptfs_decode_and_decrypt_filename(&name, &name_size,
0747fdb2	82	buf->sb, lower_name,
addd65ad MH	83	lower_namelen);
	84	if (rc) {
	85	printk(KERN_ERR "%s: Error attempting to decode and decrypt "
	86	"filename [%s]; rc = [%d]\n", __func__, lower_name,
	87	rc);
237fead6 MH	88	goto out;
237fead6 MH	89	}
2de5f059 AV	90	buf->caller->pos = buf->ctx.pos;
2de5f059 AV	91	rc = !dir_emit(buf->caller, name, name_size, ino, d_type);
addd65ad	92	kfree(name);
2de5f059	93	if (!rc)
237fead6 MH	94	buf->entries_written++;
	95	out:
	96	return rc;
	97	}
	98
	99	/**
	100	* ecryptfs_readdir
addd65ad	101	* @file: The eCryptfs directory file
2de5f059	102	* @ctx: The actor to feed the entries to
237fead6	103	*/
2de5f059	104	static int ecryptfs_readdir(struct file file, struct dir_context ctx)
237fead6 MH	105	{
	106	int rc;
	107	struct file *lower_file;
0747fdb2	108	struct inode *inode = file_inode(file);
2de5f059 AV	109	struct ecryptfs_getdents_callback buf = {
	110	.ctx.actor = ecryptfs_filldir,
	111	.caller = ctx,
0747fdb2	112	.sb = inode->i_sb,
2de5f059	113	};
237fead6	114	lower_file = ecryptfs_file_to_lower(file);
5c0ba4e0	115	rc = iterate_dir(lower_file, &buf.ctx);
2de5f059	116	ctx->pos = buf.ctx.pos;
7d6c7045 MH	117	if (rc < 0)
	118	goto out;
	119	if (buf.filldir_called && !buf.entries_written)
	120	goto out;
237fead6	121	if (rc >= 0)
7d6c7045	122	fsstack_copy_attr_atime(inode,
496ad9aa	123	file_inode(lower_file));
7d6c7045	124	out:
237fead6 MH	125	return rc;
	126	}
	127
	128	struct kmem_cache *ecryptfs_file_info_cache;
	129
e3ccaa97 TH	130	static int read_or_initialize_metadata(struct dentry *dentry)
e3ccaa97 TH	131	{
2b0143b5	132	struct inode *inode = d_inode(dentry);
e3ccaa97 TH	133	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
	134	struct ecryptfs_crypt_stat *crypt_stat;
	135	int rc;
	136
	137	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
	138	mount_crypt_stat = &ecryptfs_superblock_to_private(
	139	inode->i_sb)->mount_crypt_stat;
	140	mutex_lock(&crypt_stat->cs_mutex);
	141
	142	if (crypt_stat->flags & ECRYPTFS_POLICY_APPLIED &&
	143	crypt_stat->flags & ECRYPTFS_KEY_VALID) {
	144	rc = 0;
	145	goto out;
	146	}
	147
	148	rc = ecryptfs_read_metadata(dentry);
	149	if (!rc)
	150	goto out;
	151
	152	if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED) {
	153	crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
	154	\| ECRYPTFS_ENCRYPTED);
	155	rc = 0;
	156	goto out;
	157	}
	158
	159	if (!(mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED) &&
	160	!i_size_read(ecryptfs_inode_to_lower(inode))) {
	161	rc = ecryptfs_initialize_file(dentry, inode);
	162	if (!rc)
	163	goto out;
	164	}
	165
	166	rc = -EIO;
	167	out:
	168	mutex_unlock(&crypt_stat->cs_mutex);
	169	return rc;
	170	}
	171
237fead6 MH	172	/**
	173	* ecryptfs_open
	174	* @inode: inode speciying file to open
	175	* @file: Structure to return filled in
	176	*
	177	* Opens the file specified by inode.
	178	*
	179	* Returns zero on success; non-zero otherwise
	180	*/
	181	static int ecryptfs_open(struct inode inode, struct file file)
	182	{
	183	int rc = 0;
	184	struct ecryptfs_crypt_stat *crypt_stat = NULL;
bd243a4b	185	struct dentry *ecryptfs_dentry = file->f_path.dentry;
237fead6 MH	186	/* Private value of ecryptfs_dentry allocated in
237fead6 MH	187	* ecryptfs_lookup() */
237fead6	188	struct ecryptfs_file_info *file_info;
237fead6 MH	189
237fead6 MH	190	/* Released in ecryptfs_release or end of function if failure */
c3762229	191	file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
237fead6 MH	192	ecryptfs_set_file_private(file, file_info);
	193	if (!file_info) {
	194	ecryptfs_printk(KERN_ERR,
	195	"Error attempting to allocate memory\n");
	196	rc = -ENOMEM;
	197	goto out;
	198	}
237fead6	199	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
237fead6	200	mutex_lock(&crypt_stat->cs_mutex);
e2bd99ec	201	if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
237fead6 MH	202	ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
237fead6 MH	203	/* Policy code enabled in future release */
2ed92554 MH	204	crypt_stat->flags \|= (ECRYPTFS_POLICY_APPLIED
2ed92554 MH	205	\| ECRYPTFS_ENCRYPTED);
237fead6 MH	206	}
237fead6 MH	207	mutex_unlock(&crypt_stat->cs_mutex);
3b06b3eb	208	rc = ecryptfs_get_lower_file(ecryptfs_dentry, inode);
27992890 RS	209	if (rc) {
27992890 RS	210	printk(KERN_ERR "%s: Error attempting to initialize "
332ab16f	211	"the lower file for the dentry with name "
9e78d14a DH	212	"[%pd]; rc = [%d]\n", __func__,
9e78d14a DH	213	ecryptfs_dentry, rc);
27992890	214	goto out_free;
72b55fff	215	}
0abe1169 RS	216	if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
0abe1169 RS	217	== O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
e27759d7	218	rc = -EPERM;
332ab16f	219	printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
e27759d7	220	"file must hence be opened RO\n", __func__);
332ab16f	221	goto out_put;
e27759d7	222	}
2ed92554 MH	223	ecryptfs_set_file_lower(
2ed92554 MH	224	file, ecryptfs_inode_to_private(inode)->lower_file);
e3ccaa97 TH	225	rc = read_or_initialize_metadata(ecryptfs_dentry);
	226	if (rc)
	227	goto out_put;
888d57bb JP	228	ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = "
	229	"[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
	230	(unsigned long long)i_size_read(inode));
237fead6	231	goto out;
332ab16f TH	232	out_put:
332ab16f TH	233	ecryptfs_put_lower_file(inode);
2ed92554	234	out_free:
237fead6 MH	235	kmem_cache_free(ecryptfs_file_info_cache,
	236	ecryptfs_file_to_private(file));
	237	out:
	238	return rc;
	239	}
	240
6a480a78 AV	241	/**
	242	* ecryptfs_dir_open
	243	* @inode: inode speciying file to open
	244	* @file: Structure to return filled in
	245	*
	246	* Opens the file specified by inode.
	247	*
	248	* Returns zero on success; non-zero otherwise
	249	*/
	250	static int ecryptfs_dir_open(struct inode inode, struct file file)
	251	{
	252	struct dentry *ecryptfs_dentry = file->f_path.dentry;
	253	/* Private value of ecryptfs_dentry allocated in
	254	* ecryptfs_lookup() */
	255	struct ecryptfs_file_info *file_info;
	256	struct file *lower_file;
	257
	258	/* Released in ecryptfs_release or end of function if failure */
	259	file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
	260	ecryptfs_set_file_private(file, file_info);
	261	if (unlikely(!file_info)) {
	262	ecryptfs_printk(KERN_ERR,
	263	"Error attempting to allocate memory\n");
	264	return -ENOMEM;
	265	}
	266	lower_file = dentry_open(ecryptfs_dentry_to_lower_path(ecryptfs_dentry),
	267	file->f_flags, current_cred());
	268	if (IS_ERR(lower_file)) {
	269	printk(KERN_ERR "%s: Error attempting to initialize "
	270	"the lower file for the dentry with name "
	271	"[%pd]; rc = [%ld]\n", __func__,
	272	ecryptfs_dentry, PTR_ERR(lower_file));
	273	kmem_cache_free(ecryptfs_file_info_cache, file_info);
	274	return PTR_ERR(lower_file);
	275	}
	276	ecryptfs_set_file_lower(file, lower_file);
	277	return 0;
	278	}
	279
237fead6 MH	280	static int ecryptfs_flush(struct file *file, fl_owner_t td)
237fead6 MH	281	{
64e6651d TH	282	struct file *lower_file = ecryptfs_file_to_lower(file);
64e6651d TH	283
72c2d531	284	if (lower_file->f_op->flush) {
64e6651d TH	285	filemap_write_and_wait(file->f_mapping);
	286	return lower_file->f_op->flush(lower_file, td);
	287	}
	288
	289	return 0;
237fead6 MH	290	}
	291
	292	static int ecryptfs_release(struct inode inode, struct file file)
	293	{
332ab16f	294	ecryptfs_put_lower_file(inode);
2ed92554 MH	295	kmem_cache_free(ecryptfs_file_info_cache,
	296	ecryptfs_file_to_private(file));
	297	return 0;
237fead6 MH	298	}
237fead6 MH	299
6a480a78 AV	300	static int ecryptfs_dir_release(struct inode inode, struct file file)
	301	{
	302	fput(ecryptfs_file_to_lower(file));
	303	kmem_cache_free(ecryptfs_file_info_cache,
	304	ecryptfs_file_to_private(file));
	305	return 0;
	306	}
	307
	308	static loff_t ecryptfs_dir_llseek(struct file *file, loff_t offset, int whence)
	309	{
	310	return vfs_llseek(ecryptfs_file_to_lower(file), offset, whence);
	311	}
	312
237fead6	313	static int
02c24a82	314	ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
237fead6	315	{
bc5abcf7 TH	316	int rc;
	317
	318	rc = filemap_write_and_wait(file->f_mapping);
	319	if (rc)
	320	return rc;
	321
821f7494	322	return vfs_fsync(ecryptfs_file_to_lower(file), datasync);
237fead6 MH	323	}
	324
	325	static int ecryptfs_fasync(int fd, struct file *file, int flag)
	326	{
	327	int rc = 0;
	328	struct file *lower_file = NULL;
	329
	330	lower_file = ecryptfs_file_to_lower(file);
72c2d531	331	if (lower_file->f_op->fasync)
237fead6 MH	332	rc = lower_file->f_op->fasync(fd, lower_file, flag);
	333	return rc;
	334	}
	335
c43f7b8f TH	336	static long
	337	ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	338	{
2000f5be	339	struct file *lower_file = ecryptfs_file_to_lower(file);
c43f7b8f TH	340	long rc = -ENOTTY;
c43f7b8f TH	341
6d65261a TH	342	if (!lower_file->f_op->unlocked_ioctl)
	343	return rc;
	344
	345	switch (cmd) {
	346	case FITRIM:
	347	case FS_IOC_GETFLAGS:
	348	case FS_IOC_SETFLAGS:
	349	case FS_IOC_GETVERSION:
	350	case FS_IOC_SETVERSION:
c43f7b8f	351	rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
6d65261a TH	352	fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
	353
	354	return rc;
	355	default:
	356	return rc;
	357	}
c43f7b8f TH	358	}
	359
	360	#ifdef CONFIG_COMPAT
	361	static long
	362	ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	363	{
2000f5be	364	struct file *lower_file = ecryptfs_file_to_lower(file);
c43f7b8f TH	365	long rc = -ENOIOCTLCMD;
c43f7b8f TH	366
6d65261a TH	367	if (!lower_file->f_op->compat_ioctl)
	368	return rc;
	369
	370	switch (cmd) {
6d65261a TH	371	case FS_IOC32_GETFLAGS:
	372	case FS_IOC32_SETFLAGS:
	373	case FS_IOC32_GETVERSION:
	374	case FS_IOC32_SETVERSION:
c43f7b8f	375	rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
6d65261a TH	376	fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
	377
	378	return rc;
	379	default:
	380	return rc;
	381	}
c43f7b8f TH	382	}
c43f7b8f TH	383	#endif
237fead6 MH	384
237fead6 MH	385	const struct file_operations ecryptfs_dir_fops = {
51a16a9c	386	.iterate_shared = ecryptfs_readdir,
323ef68f	387	.read = generic_read_dir,
c43f7b8f TH	388	.unlocked_ioctl = ecryptfs_unlocked_ioctl,
	389	#ifdef CONFIG_COMPAT
	390	.compat_ioctl = ecryptfs_compat_ioctl,
	391	#endif
6a480a78 AV	392	.open = ecryptfs_dir_open,
6a480a78 AV	393	.release = ecryptfs_dir_release,
237fead6	394	.fsync = ecryptfs_fsync,
6a480a78	395	.llseek = ecryptfs_dir_llseek,
237fead6 MH	396	};
	397
	398	const struct file_operations ecryptfs_main_fops = {
53a2731f	399	.llseek = generic_file_llseek,
02797829	400	.read_iter = ecryptfs_read_update_atime,
8174202b	401	.write_iter = generic_file_write_iter,
c43f7b8f TH	402	.unlocked_ioctl = ecryptfs_unlocked_ioctl,
	403	#ifdef CONFIG_COMPAT
	404	.compat_ioctl = ecryptfs_compat_ioctl,
	405	#endif
821f7494	406	.mmap = generic_file_mmap,
237fead6 MH	407	.open = ecryptfs_open,
	408	.flush = ecryptfs_flush,
	409	.release = ecryptfs_release,
	410	.fsync = ecryptfs_fsync,
	411	.fasync = ecryptfs_fasync,
e9f6a99c	412	.splice_read = generic_file_splice_read,
237fead6	413	};