[linux-block.git] / fs / ecryptfs / file.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * 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>
 */

#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;
	const 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;
}

/*
 * ecryptfs_splice_read_update_atime
 *
 * filemap_splice_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_splice_read_update_atime(struct file *in, loff_t *ppos,
						 struct pipe_inode_info *pipe,
						 size_t len, unsigned int flags)
{
	ssize_t rc;
	const struct path *path;

	rc = filemap_splice_read(in, ppos, pipe, len, flags);
	if (rc >= 0) {
		path = ecryptfs_dentry_to_lower_path(in->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 bool
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 err;
	bool res;

	buf->filldir_called++;
	err = ecryptfs_decode_and_decrypt_filename(&name, &name_size,
						   buf->sb, lower_name,
						   lower_namelen);
	if (err) {
		if (err != -EINVAL) {
			ecryptfs_printk(KERN_DEBUG,
					"%s: Error attempting to decode and decrypt filename [%s]; rc = [%d]\n",
					__func__, lower_name, err);
			return false;
		}

		/* Mask -EINVAL errors as these are most likely due a plaintext
		 * filename present in the lower filesystem despite filename
		 * encryption being enabled. One unavoidable example would be
		 * the "lost+found" dentry in the root directory of an Ext4
		 * filesystem.
		 */
		return true;
	}

	buf->caller->pos = buf->ctx.pos;
	res = dir_emit(buf->caller, name, name_size, ino, d_type);
	kfree(name);
	if (res)
		buf->entries_written++;
	return res;
}

/**
 * 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 && (buf.entries_written || !buf.filldir_called))
		fsstack_copy_attr_atime(inode, file_inode(lower_file));
	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;
}

static int ecryptfs_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct file *lower_file = ecryptfs_file_to_lower(file);
	/*
	 * Don't allow mmap on top of file systems that don't support it
	 * natively.  If FILESYSTEM_MAX_STACK_DEPTH > 2 or ecryptfs
	 * allows recursive mounting, this will need to be extended.
	 */
	if (!lower_file->f_op->mmap)
		return -ENODEV;
	return generic_file_mmap(file, vma);
}

/**
 * ecryptfs_open
 * @inode: inode specifying 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 specifying 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 = file_write_and_wait(file);
	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 FITRIM:
	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 = ecryptfs_mmap,
	.open = ecryptfs_open,
	.flush = ecryptfs_flush,
	.release = ecryptfs_release,
	.fsync = ecryptfs_fsync,
	.fasync = ecryptfs_fasync,
	.splice_read = ecryptfs_splice_read_update_atime,
};
Commit	Line	Data
1a59d1b8	1	// SPDX-License-Identifier: GPL-2.0-or-later
a62187eb	2	/*
237fead6 MH	3	* eCryptfs: Linux filesystem encryption layer
	4	*
	5	* Copyright (C) 1997-2004 Erez Zadok
	6	* Copyright (C) 2001-2004 Stony Brook University
dd2a3b7a	7	* Copyright (C) 2004-2007 International Business Machines Corp.
237fead6 MH	8	* Author(s): Michael A. Halcrow <mhalcrow@us.ibm.com>
237fead6 MH	9	* Michael C. Thompson <mcthomps@us.ibm.com>
237fead6 MH	10	*/
	11
	12	#include <linux/file.h>
	13	#include <linux/poll.h>
5a0e3ad6	14	#include <linux/slab.h>
237fead6 MH	15	#include <linux/mount.h>
	16	#include <linux/pagemap.h>
	17	#include <linux/security.h>
237fead6	18	#include <linux/compat.h>
0cc72dc7	19	#include <linux/fs_stack.h>
237fead6 MH	20	#include "ecryptfs_kernel.h"
237fead6 MH	21
a62187eb	22	/*
237fead6 MH	23	* ecryptfs_read_update_atime
	24	*
	25	* generic_file_read updates the atime of upper layer inode. But, it
	26	* doesn't give us a chance to update the atime of the lower layer
	27	* inode. This function is a wrapper to generic_file_read. It
	28	* updates the atime of the lower level inode if generic_file_read
	29	* returns without any errors. This is to be used only for file reads.
	30	* The function to be used for directory reads is ecryptfs_read.
	31	*/
	32	static ssize_t ecryptfs_read_update_atime(struct kiocb *iocb,
02797829	33	struct iov_iter *to)
237fead6	34	{
38a708d7	35	ssize_t rc;
88569546	36	const struct path *path;
237fead6 MH	37	struct file *file = iocb->ki_filp;
237fead6 MH	38
02797829	39	rc = generic_file_read_iter(iocb, to);
237fead6	40	if (rc >= 0) {
cc18ec3c MW	41	path = ecryptfs_dentry_to_lower_path(file->f_path.dentry);
cc18ec3c MW	42	touch_atime(path);
237fead6 MH	43	}
	44	return rc;
	45	}
	46
390df3b8 DH	47	/*
	48	* ecryptfs_splice_read_update_atime
	49	*
2cb1e089	50	* filemap_splice_read updates the atime of upper layer inode. But, it
390df3b8 DH	51	* doesn't give us a chance to update the atime of the lower layer inode. This
	52	* function is a wrapper to generic_file_read. It updates the atime of the
	53	* lower level inode if generic_file_read returns without any errors. This is
	54	* to be used only for file reads. The function to be used for directory reads
	55	* is ecryptfs_read.
	56	*/
	57	static ssize_t ecryptfs_splice_read_update_atime(struct file in, loff_t ppos,
	58	struct pipe_inode_info *pipe,
	59	size_t len, unsigned int flags)
	60	{
	61	ssize_t rc;
	62	const struct path *path;
	63
2cb1e089	64	rc = filemap_splice_read(in, ppos, pipe, len, flags);
390df3b8 DH	65	if (rc >= 0) {
	66	path = ecryptfs_dentry_to_lower_path(in->f_path.dentry);
	67	touch_atime(path);
	68	}
	69	return rc;
	70	}
	71
237fead6	72	struct ecryptfs_getdents_callback {
5c0ba4e0	73	struct dir_context ctx;
2de5f059	74	struct dir_context *caller;
0747fdb2	75	struct super_block *sb;
237fead6 MH	76	int filldir_called;
	77	int entries_written;
	78	};
	79
7d6c7045	80	/* Inspired by generic filldir in fs/readdir.c */
25885a35	81	static bool
ac7576f4 MS	82	ecryptfs_filldir(struct dir_context ctx, const char lower_name,
ac7576f4 MS	83	int lower_namelen, loff_t offset, u64 ino, unsigned int d_type)
237fead6	84	{
237fead6	85	struct ecryptfs_getdents_callback *buf =
ac7576f4	86	container_of(ctx, struct ecryptfs_getdents_callback, ctx);
a8f12864	87	size_t name_size;
addd65ad	88	char *name;
25885a35 AV	89	int err;
25885a35 AV	90	bool res;
237fead6	91
237fead6	92	buf->filldir_called++;
25885a35 AV	93	err = ecryptfs_decode_and_decrypt_filename(&name, &name_size,
	94	buf->sb, lower_name,
	95	lower_namelen);
	96	if (err) {
	97	if (err != -EINVAL) {
e86281e7 TH	98	ecryptfs_printk(KERN_DEBUG,
e86281e7 TH	99	"%s: Error attempting to decode and decrypt filename [%s]; rc = [%d]\n",
25885a35 AV	100	__func__, lower_name, err);
25885a35 AV	101	return false;
e86281e7 TH	102	}
	103
	104	/* Mask -EINVAL errors as these are most likely due a plaintext
	105	* filename present in the lower filesystem despite filename
	106	* encryption being enabled. One unavoidable example would be
	107	* the "lost+found" dentry in the root directory of an Ext4
	108	* filesystem.
	109	*/
25885a35	110	return true;
237fead6	111	}
e86281e7	112
2de5f059	113	buf->caller->pos = buf->ctx.pos;
25885a35	114	res = dir_emit(buf->caller, name, name_size, ino, d_type);
addd65ad	115	kfree(name);
25885a35	116	if (res)
237fead6	117	buf->entries_written++;
25885a35	118	return res;
237fead6 MH	119	}
	120
	121	/**
	122	* ecryptfs_readdir
addd65ad	123	* @file: The eCryptfs directory file
2de5f059	124	* @ctx: The actor to feed the entries to
237fead6	125	*/
2de5f059	126	static int ecryptfs_readdir(struct file file, struct dir_context ctx)
237fead6 MH	127	{
	128	int rc;
	129	struct file *lower_file;
0747fdb2	130	struct inode *inode = file_inode(file);
2de5f059 AV	131	struct ecryptfs_getdents_callback buf = {
	132	.ctx.actor = ecryptfs_filldir,
	133	.caller = ctx,
0747fdb2	134	.sb = inode->i_sb,
2de5f059	135	};
237fead6	136	lower_file = ecryptfs_file_to_lower(file);
5c0ba4e0	137	rc = iterate_dir(lower_file, &buf.ctx);
2de5f059	138	ctx->pos = buf.ctx.pos;
25885a35 AV	139	if (rc >= 0 && (buf.entries_written \|\| !buf.filldir_called))
25885a35 AV	140	fsstack_copy_attr_atime(inode, file_inode(lower_file));
237fead6 MH	141	return rc;
	142	}
	143
	144	struct kmem_cache *ecryptfs_file_info_cache;
	145
e3ccaa97 TH	146	static int read_or_initialize_metadata(struct dentry *dentry)
e3ccaa97 TH	147	{
2b0143b5	148	struct inode *inode = d_inode(dentry);
e3ccaa97 TH	149	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
	150	struct ecryptfs_crypt_stat *crypt_stat;
	151	int rc;
	152
	153	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
	154	mount_crypt_stat = &ecryptfs_superblock_to_private(
	155	inode->i_sb)->mount_crypt_stat;
	156	mutex_lock(&crypt_stat->cs_mutex);
	157
	158	if (crypt_stat->flags & ECRYPTFS_POLICY_APPLIED &&
	159	crypt_stat->flags & ECRYPTFS_KEY_VALID) {
	160	rc = 0;
	161	goto out;
	162	}
	163
	164	rc = ecryptfs_read_metadata(dentry);
	165	if (!rc)
	166	goto out;
	167
	168	if (mount_crypt_stat->flags & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED) {
	169	crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
	170	\| ECRYPTFS_ENCRYPTED);
	171	rc = 0;
	172	goto out;
	173	}
	174
	175	if (!(mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED) &&
	176	!i_size_read(ecryptfs_inode_to_lower(inode))) {
	177	rc = ecryptfs_initialize_file(dentry, inode);
	178	if (!rc)
	179	goto out;
	180	}
	181
	182	rc = -EIO;
	183	out:
	184	mutex_unlock(&crypt_stat->cs_mutex);
	185	return rc;
	186	}
	187
f0fe970d JM	188	static int ecryptfs_mmap(struct file file, struct vm_area_struct vma)
	189	{
	190	struct file *lower_file = ecryptfs_file_to_lower(file);
	191	/*
	192	* Don't allow mmap on top of file systems that don't support it
	193	* natively. If FILESYSTEM_MAX_STACK_DEPTH > 2 or ecryptfs
	194	* allows recursive mounting, this will need to be extended.
	195	*/
	196	if (!lower_file->f_op->mmap)
	197	return -ENODEV;
	198	return generic_file_mmap(file, vma);
	199	}
	200
237fead6 MH	201	/**
237fead6 MH	202	* ecryptfs_open
40f0fd37	203	* @inode: inode specifying file to open
237fead6 MH	204	* @file: Structure to return filled in
	205	*
	206	* Opens the file specified by inode.
	207	*
	208	* Returns zero on success; non-zero otherwise
	209	*/
	210	static int ecryptfs_open(struct inode inode, struct file file)
	211	{
	212	int rc = 0;
	213	struct ecryptfs_crypt_stat *crypt_stat = NULL;
bd243a4b	214	struct dentry *ecryptfs_dentry = file->f_path.dentry;
237fead6 MH	215	/* Private value of ecryptfs_dentry allocated in
237fead6 MH	216	* ecryptfs_lookup() */
237fead6	217	struct ecryptfs_file_info *file_info;
237fead6 MH	218
237fead6 MH	219	/* Released in ecryptfs_release or end of function if failure */
c3762229	220	file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
237fead6 MH	221	ecryptfs_set_file_private(file, file_info);
	222	if (!file_info) {
	223	ecryptfs_printk(KERN_ERR,
	224	"Error attempting to allocate memory\n");
	225	rc = -ENOMEM;
	226	goto out;
	227	}
237fead6	228	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
237fead6	229	mutex_lock(&crypt_stat->cs_mutex);
e2bd99ec	230	if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
237fead6 MH	231	ecryptfs_printk(KERN_DEBUG, "Setting flags for stat...\n");
237fead6 MH	232	/* Policy code enabled in future release */
2ed92554 MH	233	crypt_stat->flags \|= (ECRYPTFS_POLICY_APPLIED
2ed92554 MH	234	\| ECRYPTFS_ENCRYPTED);
237fead6 MH	235	}
237fead6 MH	236	mutex_unlock(&crypt_stat->cs_mutex);
3b06b3eb	237	rc = ecryptfs_get_lower_file(ecryptfs_dentry, inode);
27992890 RS	238	if (rc) {
27992890 RS	239	printk(KERN_ERR "%s: Error attempting to initialize "
332ab16f	240	"the lower file for the dentry with name "
9e78d14a DH	241	"[%pd]; rc = [%d]\n", __func__,
9e78d14a DH	242	ecryptfs_dentry, rc);
27992890	243	goto out_free;
72b55fff	244	}
0abe1169 RS	245	if ((ecryptfs_inode_to_private(inode)->lower_file->f_flags & O_ACCMODE)
0abe1169 RS	246	== O_RDONLY && (file->f_flags & O_ACCMODE) != O_RDONLY) {
e27759d7	247	rc = -EPERM;
332ab16f	248	printk(KERN_WARNING "%s: Lower file is RO; eCryptfs "
e27759d7	249	"file must hence be opened RO\n", __func__);
332ab16f	250	goto out_put;
e27759d7	251	}
2ed92554 MH	252	ecryptfs_set_file_lower(
2ed92554 MH	253	file, ecryptfs_inode_to_private(inode)->lower_file);
e3ccaa97 TH	254	rc = read_or_initialize_metadata(ecryptfs_dentry);
	255	if (rc)
	256	goto out_put;
888d57bb JP	257	ecryptfs_printk(KERN_DEBUG, "inode w/ addr = [0x%p], i_ino = "
	258	"[0x%.16lx] size: [0x%.16llx]\n", inode, inode->i_ino,
	259	(unsigned long long)i_size_read(inode));
237fead6	260	goto out;
332ab16f TH	261	out_put:
332ab16f TH	262	ecryptfs_put_lower_file(inode);
2ed92554	263	out_free:
237fead6 MH	264	kmem_cache_free(ecryptfs_file_info_cache,
	265	ecryptfs_file_to_private(file));
	266	out:
	267	return rc;
	268	}
	269
6a480a78 AV	270	/**
6a480a78 AV	271	* ecryptfs_dir_open
40f0fd37	272	* @inode: inode specifying file to open
6a480a78 AV	273	* @file: Structure to return filled in
	274	*
	275	* Opens the file specified by inode.
	276	*
	277	* Returns zero on success; non-zero otherwise
	278	*/
	279	static int ecryptfs_dir_open(struct inode inode, struct file file)
	280	{
	281	struct dentry *ecryptfs_dentry = file->f_path.dentry;
	282	/* Private value of ecryptfs_dentry allocated in
	283	* ecryptfs_lookup() */
	284	struct ecryptfs_file_info *file_info;
	285	struct file *lower_file;
	286
	287	/* Released in ecryptfs_release or end of function if failure */
	288	file_info = kmem_cache_zalloc(ecryptfs_file_info_cache, GFP_KERNEL);
	289	ecryptfs_set_file_private(file, file_info);
	290	if (unlikely(!file_info)) {
	291	ecryptfs_printk(KERN_ERR,
	292	"Error attempting to allocate memory\n");
	293	return -ENOMEM;
	294	}
	295	lower_file = dentry_open(ecryptfs_dentry_to_lower_path(ecryptfs_dentry),
	296	file->f_flags, current_cred());
	297	if (IS_ERR(lower_file)) {
	298	printk(KERN_ERR "%s: Error attempting to initialize "
	299	"the lower file for the dentry with name "
	300	"[%pd]; rc = [%ld]\n", __func__,
	301	ecryptfs_dentry, PTR_ERR(lower_file));
	302	kmem_cache_free(ecryptfs_file_info_cache, file_info);
	303	return PTR_ERR(lower_file);
	304	}
	305	ecryptfs_set_file_lower(file, lower_file);
	306	return 0;
	307	}
	308
237fead6 MH	309	static int ecryptfs_flush(struct file *file, fl_owner_t td)
237fead6 MH	310	{
64e6651d TH	311	struct file *lower_file = ecryptfs_file_to_lower(file);
64e6651d TH	312
72c2d531	313	if (lower_file->f_op->flush) {
64e6651d TH	314	filemap_write_and_wait(file->f_mapping);
	315	return lower_file->f_op->flush(lower_file, td);
	316	}
	317
	318	return 0;
237fead6 MH	319	}
	320
	321	static int ecryptfs_release(struct inode inode, struct file file)
	322	{
332ab16f	323	ecryptfs_put_lower_file(inode);
2ed92554 MH	324	kmem_cache_free(ecryptfs_file_info_cache,
	325	ecryptfs_file_to_private(file));
	326	return 0;
237fead6 MH	327	}
237fead6 MH	328
6a480a78 AV	329	static int ecryptfs_dir_release(struct inode inode, struct file file)
	330	{
	331	fput(ecryptfs_file_to_lower(file));
	332	kmem_cache_free(ecryptfs_file_info_cache,
	333	ecryptfs_file_to_private(file));
	334	return 0;
	335	}
	336
	337	static loff_t ecryptfs_dir_llseek(struct file *file, loff_t offset, int whence)
	338	{
	339	return vfs_llseek(ecryptfs_file_to_lower(file), offset, whence);
	340	}
	341
237fead6	342	static int
02c24a82	343	ecryptfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
237fead6	344	{
bc5abcf7 TH	345	int rc;
bc5abcf7 TH	346
6d4b5124	347	rc = file_write_and_wait(file);
bc5abcf7 TH	348	if (rc)
	349	return rc;
	350
821f7494	351	return vfs_fsync(ecryptfs_file_to_lower(file), datasync);
237fead6 MH	352	}
	353
	354	static int ecryptfs_fasync(int fd, struct file *file, int flag)
	355	{
	356	int rc = 0;
	357	struct file *lower_file = NULL;
	358
	359	lower_file = ecryptfs_file_to_lower(file);
72c2d531	360	if (lower_file->f_op->fasync)
237fead6 MH	361	rc = lower_file->f_op->fasync(fd, lower_file, flag);
	362	return rc;
	363	}
	364
c43f7b8f TH	365	static long
	366	ecryptfs_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	367	{
2000f5be	368	struct file *lower_file = ecryptfs_file_to_lower(file);
c43f7b8f TH	369	long rc = -ENOTTY;
c43f7b8f TH	370
6d65261a TH	371	if (!lower_file->f_op->unlocked_ioctl)
	372	return rc;
	373
	374	switch (cmd) {
	375	case FITRIM:
	376	case FS_IOC_GETFLAGS:
	377	case FS_IOC_SETFLAGS:
	378	case FS_IOC_GETVERSION:
	379	case FS_IOC_SETVERSION:
c43f7b8f	380	rc = lower_file->f_op->unlocked_ioctl(lower_file, cmd, arg);
6d65261a TH	381	fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
	382
	383	return rc;
	384	default:
	385	return rc;
	386	}
c43f7b8f TH	387	}
	388
	389	#ifdef CONFIG_COMPAT
	390	static long
	391	ecryptfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	392	{
2000f5be	393	struct file *lower_file = ecryptfs_file_to_lower(file);
c43f7b8f TH	394	long rc = -ENOIOCTLCMD;
c43f7b8f TH	395
6d65261a TH	396	if (!lower_file->f_op->compat_ioctl)
	397	return rc;
	398
	399	switch (cmd) {
314999dc	400	case FITRIM:
6d65261a TH	401	case FS_IOC32_GETFLAGS:
	402	case FS_IOC32_SETFLAGS:
	403	case FS_IOC32_GETVERSION:
	404	case FS_IOC32_SETVERSION:
c43f7b8f	405	rc = lower_file->f_op->compat_ioctl(lower_file, cmd, arg);
6d65261a TH	406	fsstack_copy_attr_all(file_inode(file), file_inode(lower_file));
	407
	408	return rc;
	409	default:
	410	return rc;
	411	}
c43f7b8f TH	412	}
c43f7b8f TH	413	#endif
237fead6 MH	414
237fead6 MH	415	const struct file_operations ecryptfs_dir_fops = {
51a16a9c	416	.iterate_shared = ecryptfs_readdir,
323ef68f	417	.read = generic_read_dir,
c43f7b8f TH	418	.unlocked_ioctl = ecryptfs_unlocked_ioctl,
	419	#ifdef CONFIG_COMPAT
	420	.compat_ioctl = ecryptfs_compat_ioctl,
	421	#endif
6a480a78 AV	422	.open = ecryptfs_dir_open,
6a480a78 AV	423	.release = ecryptfs_dir_release,
237fead6	424	.fsync = ecryptfs_fsync,
6a480a78	425	.llseek = ecryptfs_dir_llseek,
237fead6 MH	426	};
	427
	428	const struct file_operations ecryptfs_main_fops = {
53a2731f	429	.llseek = generic_file_llseek,
02797829	430	.read_iter = ecryptfs_read_update_atime,
8174202b	431	.write_iter = generic_file_write_iter,
c43f7b8f TH	432	.unlocked_ioctl = ecryptfs_unlocked_ioctl,
	433	#ifdef CONFIG_COMPAT
	434	.compat_ioctl = ecryptfs_compat_ioctl,
	435	#endif
f0fe970d	436	.mmap = ecryptfs_mmap,
237fead6 MH	437	.open = ecryptfs_open,
	438	.flush = ecryptfs_flush,
	439	.release = ecryptfs_release,
	440	.fsync = ecryptfs_fsync,
	441	.fasync = ecryptfs_fasync,
390df3b8	442	.splice_read = ecryptfs_splice_read_update_atime,
237fead6	443	};