[linux-2.6-block.git] / include / linux / fscrypto.h

/*
 * General per-file encryption definition
 *
 * Copyright (C) 2015, Google, Inc.
 *
 * Written by Michael Halcrow, 2015.
 * Modified by Jaegeuk Kim, 2015.
 */

#ifndef _LINUX_FSCRYPTO_H
#define _LINUX_FSCRYPTO_H

#include <linux/key.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/bio.h>
#include <linux/dcache.h>
#include <crypto/skcipher.h>
#include <uapi/linux/fs.h>

#define FS_KEY_DERIVATION_NONCE_SIZE		16
#define FS_ENCRYPTION_CONTEXT_FORMAT_V1		1

#define FS_POLICY_FLAGS_PAD_4		0x00
#define FS_POLICY_FLAGS_PAD_8		0x01
#define FS_POLICY_FLAGS_PAD_16		0x02
#define FS_POLICY_FLAGS_PAD_32		0x03
#define FS_POLICY_FLAGS_PAD_MASK	0x03
#define FS_POLICY_FLAGS_VALID		0x03

/* Encryption algorithms */
#define FS_ENCRYPTION_MODE_INVALID		0
#define FS_ENCRYPTION_MODE_AES_256_XTS		1
#define FS_ENCRYPTION_MODE_AES_256_GCM		2
#define FS_ENCRYPTION_MODE_AES_256_CBC		3
#define FS_ENCRYPTION_MODE_AES_256_CTS		4

/**
 * Encryption context for inode
 *
 * Protector format:
 *  1 byte: Protector format (1 = this version)
 *  1 byte: File contents encryption mode
 *  1 byte: File names encryption mode
 *  1 byte: Flags
 *  8 bytes: Master Key descriptor
 *  16 bytes: Encryption Key derivation nonce
 */
struct fscrypt_context {
	u8 format;
	u8 contents_encryption_mode;
	u8 filenames_encryption_mode;
	u8 flags;
	u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
	u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
} __packed;

/* Encryption parameters */
#define FS_XTS_TWEAK_SIZE		16
#define FS_AES_128_ECB_KEY_SIZE		16
#define FS_AES_256_GCM_KEY_SIZE		32
#define FS_AES_256_CBC_KEY_SIZE		32
#define FS_AES_256_CTS_KEY_SIZE		32
#define FS_AES_256_XTS_KEY_SIZE		64
#define FS_MAX_KEY_SIZE			64

#define FS_KEY_DESC_PREFIX		"fscrypt:"
#define FS_KEY_DESC_PREFIX_SIZE		8

/* This is passed in from userspace into the kernel keyring */
struct fscrypt_key {
	u32 mode;
	u8 raw[FS_MAX_KEY_SIZE];
	u32 size;
} __packed;

struct fscrypt_info {
	u8 ci_data_mode;
	u8 ci_filename_mode;
	u8 ci_flags;
	struct crypto_skcipher *ci_ctfm;
	struct key *ci_keyring_key;
	u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
};

#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL		0x00000001
#define FS_WRITE_PATH_FL			0x00000002

struct fscrypt_ctx {
	union {
		struct {
			struct page *bounce_page;	/* Ciphertext page */
			struct page *control_page;	/* Original page  */
		} w;
		struct {
			struct bio *bio;
			struct work_struct work;
		} r;
		struct list_head free_list;	/* Free list */
	};
	u8 flags;				/* Flags */
	u8 mode;				/* Encryption mode for tfm */
};

struct fscrypt_completion_result {
	struct completion completion;
	int res;
};

#define DECLARE_FS_COMPLETION_RESULT(ecr) \
	struct fscrypt_completion_result ecr = { \
		COMPLETION_INITIALIZER((ecr).completion), 0 }

static inline int fscrypt_key_size(int mode)
{
	switch (mode) {
	case FS_ENCRYPTION_MODE_AES_256_XTS:
		return FS_AES_256_XTS_KEY_SIZE;
	case FS_ENCRYPTION_MODE_AES_256_GCM:
		return FS_AES_256_GCM_KEY_SIZE;
	case FS_ENCRYPTION_MODE_AES_256_CBC:
		return FS_AES_256_CBC_KEY_SIZE;
	case FS_ENCRYPTION_MODE_AES_256_CTS:
		return FS_AES_256_CTS_KEY_SIZE;
	default:
		BUG();
	}
	return 0;
}

#define FS_FNAME_NUM_SCATTER_ENTRIES	4
#define FS_CRYPTO_BLOCK_SIZE		16
#define FS_FNAME_CRYPTO_DIGEST_SIZE	32

/**
 * For encrypted symlinks, the ciphertext length is stored at the beginning
 * of the string in little-endian format.
 */
struct fscrypt_symlink_data {
	__le16 len;
	char encrypted_path[1];
} __packed;

/**
 * This function is used to calculate the disk space required to
 * store a filename of length l in encrypted symlink format.
 */
static inline u32 fscrypt_symlink_data_len(u32 l)
{
	if (l < FS_CRYPTO_BLOCK_SIZE)
		l = FS_CRYPTO_BLOCK_SIZE;
	return (l + sizeof(struct fscrypt_symlink_data) - 1);
}

struct fscrypt_str {
	unsigned char *name;
	u32 len;
};

struct fscrypt_name {
	const struct qstr *usr_fname;
	struct fscrypt_str disk_name;
	u32 hash;
	u32 minor_hash;
	struct fscrypt_str crypto_buf;
};

#define FSTR_INIT(n, l)		{ .name = n, .len = l }
#define FSTR_TO_QSTR(f)		QSTR_INIT((f)->name, (f)->len)
#define fname_name(p)		((p)->disk_name.name)
#define fname_len(p)		((p)->disk_name.len)

/*
 * crypto opertions for filesystems
 */
struct fscrypt_operations {
	int (*get_context)(struct inode *, void *, size_t);
	int (*prepare_context)(struct inode *);
	int (*set_context)(struct inode *, const void *, size_t, void *);
	int (*dummy_context)(struct inode *);
	bool (*is_encrypted)(struct inode *);
	bool (*empty_dir)(struct inode *);
	unsigned (*max_namelen)(struct inode *);
};

static inline bool fscrypt_dummy_context_enabled(struct inode *inode)
{
	if (inode->i_sb->s_cop->dummy_context &&
				inode->i_sb->s_cop->dummy_context(inode))
		return true;
	return false;
}

static inline bool fscrypt_valid_contents_enc_mode(u32 mode)
{
	return (mode == FS_ENCRYPTION_MODE_AES_256_XTS);
}

static inline bool fscrypt_valid_filenames_enc_mode(u32 mode)
{
	return (mode == FS_ENCRYPTION_MODE_AES_256_CTS);
}

static inline u32 fscrypt_validate_encryption_key_size(u32 mode, u32 size)
{
	if (size == fscrypt_key_size(mode))
		return size;
	return 0;
}

static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
{
	if (str->len == 1 && str->name[0] == '.')
		return true;

	if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
		return true;

	return false;
}

static inline struct page *fscrypt_control_page(struct page *page)
{
#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	return ((struct fscrypt_ctx *)page_private(page))->w.control_page;
#else
	WARN_ON_ONCE(1);
	return ERR_PTR(-EINVAL);
#endif
}

static inline int fscrypt_has_encryption_key(struct inode *inode)
{
#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	return (inode->i_crypt_info != NULL);
#else
	return 0;
#endif
}

static inline void fscrypt_set_encrypted_dentry(struct dentry *dentry)
{
#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	spin_lock(&dentry->d_lock);
	dentry->d_flags |= DCACHE_ENCRYPTED_WITH_KEY;
	spin_unlock(&dentry->d_lock);
#endif
}

#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
extern const struct dentry_operations fscrypt_d_ops;
#endif

static inline void fscrypt_set_d_op(struct dentry *dentry)
{
#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	d_set_d_op(dentry, &fscrypt_d_ops);
#endif
}

#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
/* crypto.c */
extern struct kmem_cache *fscrypt_info_cachep;
int fscrypt_initialize(void);

extern struct fscrypt_ctx *fscrypt_get_ctx(struct inode *, gfp_t);
extern void fscrypt_release_ctx(struct fscrypt_ctx *);
extern struct page *fscrypt_encrypt_page(struct inode *, struct page *, gfp_t);
extern int fscrypt_decrypt_page(struct page *);
extern void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *, struct bio *);
extern void fscrypt_pullback_bio_page(struct page **, bool);
extern void fscrypt_restore_control_page(struct page *);
extern int fscrypt_zeroout_range(struct inode *, pgoff_t, sector_t,
						unsigned int);
/* policy.c */
extern int fscrypt_process_policy(struct inode *,
					const struct fscrypt_policy *);
extern int fscrypt_get_policy(struct inode *, struct fscrypt_policy *);
extern int fscrypt_has_permitted_context(struct inode *, struct inode *);
extern int fscrypt_inherit_context(struct inode *, struct inode *,
					void *, bool);
/* keyinfo.c */
extern int get_crypt_info(struct inode *);
extern int fscrypt_get_encryption_info(struct inode *);
extern void fscrypt_put_encryption_info(struct inode *, struct fscrypt_info *);

/* fname.c */
extern int fscrypt_setup_filename(struct inode *, const struct qstr *,
				int lookup, struct fscrypt_name *);
extern void fscrypt_free_filename(struct fscrypt_name *);
extern u32 fscrypt_fname_encrypted_size(struct inode *, u32);
extern int fscrypt_fname_alloc_buffer(struct inode *, u32,
				struct fscrypt_str *);
extern void fscrypt_fname_free_buffer(struct fscrypt_str *);
extern int fscrypt_fname_disk_to_usr(struct inode *, u32, u32,
			const struct fscrypt_str *, struct fscrypt_str *);
extern int fscrypt_fname_usr_to_disk(struct inode *, const struct qstr *,
			struct fscrypt_str *);
#endif

/* crypto.c */
static inline struct fscrypt_ctx *fscrypt_notsupp_get_ctx(struct inode *i,
							gfp_t f)
{
	return ERR_PTR(-EOPNOTSUPP);
}

static inline void fscrypt_notsupp_release_ctx(struct fscrypt_ctx *c)
{
	return;
}

static inline struct page *fscrypt_notsupp_encrypt_page(struct inode *i,
						struct page *p, gfp_t f)
{
	return ERR_PTR(-EOPNOTSUPP);
}

static inline int fscrypt_notsupp_decrypt_page(struct page *p)
{
	return -EOPNOTSUPP;
}

static inline void fscrypt_notsupp_decrypt_bio_pages(struct fscrypt_ctx *c,
						struct bio *b)
{
	return;
}

static inline void fscrypt_notsupp_pullback_bio_page(struct page **p, bool b)
{
	return;
}

static inline void fscrypt_notsupp_restore_control_page(struct page *p)
{
	return;
}

static inline int fscrypt_notsupp_zeroout_range(struct inode *i, pgoff_t p,
					sector_t s, unsigned int f)
{
	return -EOPNOTSUPP;
}

/* policy.c */
static inline int fscrypt_notsupp_process_policy(struct inode *i,
				const struct fscrypt_policy *p)
{
	return -EOPNOTSUPP;
}

static inline int fscrypt_notsupp_get_policy(struct inode *i,
				struct fscrypt_policy *p)
{
	return -EOPNOTSUPP;
}

static inline int fscrypt_notsupp_has_permitted_context(struct inode *p,
				struct inode *i)
{
	return 0;
}

static inline int fscrypt_notsupp_inherit_context(struct inode *p,
				struct inode *i, void *v, bool b)
{
	return -EOPNOTSUPP;
}

/* keyinfo.c */
static inline int fscrypt_notsupp_get_encryption_info(struct inode *i)
{
	return -EOPNOTSUPP;
}

static inline void fscrypt_notsupp_put_encryption_info(struct inode *i,
					struct fscrypt_info *f)
{
	return;
}

 /* fname.c */
static inline int fscrypt_notsupp_setup_filename(struct inode *dir,
			const struct qstr *iname,
			int lookup, struct fscrypt_name *fname)
{
	if (dir->i_sb->s_cop->is_encrypted(dir))
		return -EOPNOTSUPP;

	memset(fname, 0, sizeof(struct fscrypt_name));
	fname->usr_fname = iname;
	fname->disk_name.name = (unsigned char *)iname->name;
	fname->disk_name.len = iname->len;
	return 0;
}

static inline void fscrypt_notsupp_free_filename(struct fscrypt_name *fname)
{
	return;
}

static inline u32 fscrypt_notsupp_fname_encrypted_size(struct inode *i, u32 s)
{
	/* never happens */
	WARN_ON(1);
	return 0;
}

static inline int fscrypt_notsupp_fname_alloc_buffer(struct inode *inode,
				u32 ilen, struct fscrypt_str *crypto_str)
{
	return -EOPNOTSUPP;
}

static inline void fscrypt_notsupp_fname_free_buffer(struct fscrypt_str *c)
{
	return;
}

static inline int fscrypt_notsupp_fname_disk_to_usr(struct inode *inode,
			u32 hash, u32 minor_hash,
			const struct fscrypt_str *iname,
			struct fscrypt_str *oname)
{
	return -EOPNOTSUPP;
}

static inline int fscrypt_notsupp_fname_usr_to_disk(struct inode *inode,
			const struct qstr *iname,
			struct fscrypt_str *oname)
{
	return -EOPNOTSUPP;
}
#endif	/* _LINUX_FSCRYPTO_H */
Commit	Line	Data
0b81d077 JK	1	/*
	2	* General per-file encryption definition
	3	*
	4	* Copyright (C) 2015, Google, Inc.
	5	*
	6	* Written by Michael Halcrow, 2015.
	7	* Modified by Jaegeuk Kim, 2015.
	8	*/
	9
	10	#ifndef _LINUX_FSCRYPTO_H
	11	#define _LINUX_FSCRYPTO_H
	12
	13	#include <linux/key.h>
	14	#include <linux/fs.h>
	15	#include <linux/mm.h>
	16	#include <linux/bio.h>
	17	#include <linux/dcache.h>
d407574e	18	#include <crypto/skcipher.h>
0b81d077 JK	19	#include <uapi/linux/fs.h>
	20
	21	#define FS_KEY_DERIVATION_NONCE_SIZE 16
	22	#define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
	23
	24	#define FS_POLICY_FLAGS_PAD_4 0x00
	25	#define FS_POLICY_FLAGS_PAD_8 0x01
	26	#define FS_POLICY_FLAGS_PAD_16 0x02
	27	#define FS_POLICY_FLAGS_PAD_32 0x03
	28	#define FS_POLICY_FLAGS_PAD_MASK 0x03
	29	#define FS_POLICY_FLAGS_VALID 0x03
	30
	31	/* Encryption algorithms */
	32	#define FS_ENCRYPTION_MODE_INVALID 0
	33	#define FS_ENCRYPTION_MODE_AES_256_XTS 1
	34	#define FS_ENCRYPTION_MODE_AES_256_GCM 2
	35	#define FS_ENCRYPTION_MODE_AES_256_CBC 3
	36	#define FS_ENCRYPTION_MODE_AES_256_CTS 4
	37
	38	/**
	39	* Encryption context for inode
	40	*
	41	* Protector format:
	42	* 1 byte: Protector format (1 = this version)
	43	* 1 byte: File contents encryption mode
	44	* 1 byte: File names encryption mode
	45	* 1 byte: Flags
	46	* 8 bytes: Master Key descriptor
	47	* 16 bytes: Encryption Key derivation nonce
	48	*/
	49	struct fscrypt_context {
	50	u8 format;
	51	u8 contents_encryption_mode;
	52	u8 filenames_encryption_mode;
	53	u8 flags;
	54	u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
	55	u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
	56	} __packed;
	57
	58	/* Encryption parameters */
	59	#define FS_XTS_TWEAK_SIZE 16
	60	#define FS_AES_128_ECB_KEY_SIZE 16
	61	#define FS_AES_256_GCM_KEY_SIZE 32
	62	#define FS_AES_256_CBC_KEY_SIZE 32
	63	#define FS_AES_256_CTS_KEY_SIZE 32
	64	#define FS_AES_256_XTS_KEY_SIZE 64
	65	#define FS_MAX_KEY_SIZE 64
	66
	67	#define FS_KEY_DESC_PREFIX "fscrypt:"
	68	#define FS_KEY_DESC_PREFIX_SIZE 8
	69
	70	/* This is passed in from userspace into the kernel keyring */
	71	struct fscrypt_key {
	72	u32 mode;
	73	u8 raw[FS_MAX_KEY_SIZE];
	74	u32 size;
	75	} __packed;
	76
	77	struct fscrypt_info {
	78	u8 ci_data_mode;
	79	u8 ci_filename_mode;
	80	u8 ci_flags;
d407574e	81	struct crypto_skcipher *ci_ctfm;
0b81d077 JK	82	struct key *ci_keyring_key;
	83	u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
	84	};
	85
	86	#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
	87	#define FS_WRITE_PATH_FL 0x00000002
	88
	89	struct fscrypt_ctx {
	90	union {
	91	struct {
	92	struct page bounce_page; / Ciphertext page */
	93	struct page control_page; / Original page */
	94	} w;
	95	struct {
	96	struct bio *bio;
	97	struct work_struct work;
	98	} r;
	99	struct list_head free_list; /* Free list */
	100	};
	101	u8 flags; /* Flags */
	102	u8 mode; /* Encryption mode for tfm */
	103	};
	104
	105	struct fscrypt_completion_result {
	106	struct completion completion;
	107	int res;
	108	};
	109
	110	#define DECLARE_FS_COMPLETION_RESULT(ecr) \
	111	struct fscrypt_completion_result ecr = { \
	112	COMPLETION_INITIALIZER((ecr).completion), 0 }
	113
	114	static inline int fscrypt_key_size(int mode)
	115	{
	116	switch (mode) {
	117	case FS_ENCRYPTION_MODE_AES_256_XTS:
	118	return FS_AES_256_XTS_KEY_SIZE;
	119	case FS_ENCRYPTION_MODE_AES_256_GCM:
	120	return FS_AES_256_GCM_KEY_SIZE;
	121	case FS_ENCRYPTION_MODE_AES_256_CBC:
	122	return FS_AES_256_CBC_KEY_SIZE;
	123	case FS_ENCRYPTION_MODE_AES_256_CTS:
	124	return FS_AES_256_CTS_KEY_SIZE;
	125	default:
	126	BUG();
	127	}
	128	return 0;
	129	}
	130
	131	#define FS_FNAME_NUM_SCATTER_ENTRIES 4
	132	#define FS_CRYPTO_BLOCK_SIZE 16
	133	#define FS_FNAME_CRYPTO_DIGEST_SIZE 32
	134
	135	/**
	136	* For encrypted symlinks, the ciphertext length is stored at the beginning
	137	* of the string in little-endian format.
	138	*/
	139	struct fscrypt_symlink_data {
	140	__le16 len;
	141	char encrypted_path[1];
	142	} __packed;
	143
	144	/**
	145	* This function is used to calculate the disk space required to
146	* store a filename of length l in encrypted symlink format.
147	*/
148	static inline u32 fscrypt_symlink_data_len(u32 l)
149	{
150	if (l < FS_CRYPTO_BLOCK_SIZE)
151	l = FS_CRYPTO_BLOCK_SIZE;
152	return (l + sizeof(struct fscrypt_symlink_data) - 1);
153	}
154
155	struct fscrypt_str {
156	unsigned char *name;
157	u32 len;
158	};
159
160	struct fscrypt_name {
161	const struct qstr *usr_fname;
162	struct fscrypt_str disk_name;
163	u32 hash;
164	u32 minor_hash;
165	struct fscrypt_str crypto_buf;
166	};
167
168	#define FSTR_INIT(n, l) { .name = n, .len = l }
169	#define FSTR_TO_QSTR(f) QSTR_INIT((f)->name, (f)->len)
170	#define fname_name(p) ((p)->disk_name.name)
171	#define fname_len(p) ((p)->disk_name.len)
172
173	/*
174	* crypto opertions for filesystems
175	*/
176	struct fscrypt_operations {
177	int (get_context)(struct inode , void *, size_t);
178	int (prepare_context)(struct inode );
179	int (set_context)(struct inode , const void , size_t, void );
180	int (dummy_context)(struct inode );
181	bool (is_encrypted)(struct inode );
182	bool (empty_dir)(struct inode );
183	unsigned (max_namelen)(struct inode );
184	};
185
186	static inline bool fscrypt_dummy_context_enabled(struct inode *inode)
187	{
188	if (inode->i_sb->s_cop->dummy_context &&
189	inode->i_sb->s_cop->dummy_context(inode))
190	return true;
191	return false;
192	}
193
194	static inline bool fscrypt_valid_contents_enc_mode(u32 mode)
195	{
196	return (mode == FS_ENCRYPTION_MODE_AES_256_XTS);
197	}
198
199	static inline bool fscrypt_valid_filenames_enc_mode(u32 mode)
200	{
201	return (mode == FS_ENCRYPTION_MODE_AES_256_CTS);
202	}
203
204	static inline u32 fscrypt_validate_encryption_key_size(u32 mode, u32 size)
205	{
206	if (size == fscrypt_key_size(mode))
207	return size;
208	return 0;
209	}
210
211	static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
212	{
213	if (str->len == 1 && str->name[0] == '.')
214	return true;
215
216	if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
217	return true;
218
219	return false;
220	}
221
222	static inline struct page fscrypt_control_page(struct page page)
223	{
224	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
225	return ((struct fscrypt_ctx *)page_private(page))->w.control_page;
226	#else
227	WARN_ON_ONCE(1);
228	return ERR_PTR(-EINVAL);
229	#endif
230	}
231
232	static inline int fscrypt_has_encryption_key(struct inode *inode)
233	{
234	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
235	return (inode->i_crypt_info != NULL);
236	#else
237	return 0;
238	#endif
239	}
240
241	static inline void fscrypt_set_encrypted_dentry(struct dentry *dentry)
242	{
243	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
244	spin_lock(&dentry->d_lock);
245	dentry->d_flags \|= DCACHE_ENCRYPTED_WITH_KEY;
246	spin_unlock(&dentry->d_lock);
247	#endif
248	}
249
250	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
251	extern const struct dentry_operations fscrypt_d_ops;
252	#endif
253
254	static inline void fscrypt_set_d_op(struct dentry *dentry)
255	{
256	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
257	d_set_d_op(dentry, &fscrypt_d_ops);
258	#endif
259	}
260
261	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
262	/* crypto.c */
263	extern struct kmem_cache *fscrypt_info_cachep;
264	int fscrypt_initialize(void);
265
b32e4482	266	extern struct fscrypt_ctx fscrypt_get_ctx(struct inode , gfp_t);
0b81d077	267	extern void fscrypt_release_ctx(struct fscrypt_ctx *);
b32e4482	268	extern struct page fscrypt_encrypt_page(struct inode , struct page *, gfp_t);
0b81d077 JK	269	extern int fscrypt_decrypt_page(struct page *);
	270	extern void fscrypt_decrypt_bio_pages(struct fscrypt_ctx , struct bio );
	271	extern void fscrypt_pullback_bio_page(struct page **, bool);
	272	extern void fscrypt_restore_control_page(struct page *);
	273	extern int fscrypt_zeroout_range(struct inode *, pgoff_t, sector_t,
	274	unsigned int);
	275	/* policy.c */
	276	extern int fscrypt_process_policy(struct inode *,
	277	const struct fscrypt_policy *);
	278	extern int fscrypt_get_policy(struct inode , struct fscrypt_policy );
	279	extern int fscrypt_has_permitted_context(struct inode , struct inode );
	280	extern int fscrypt_inherit_context(struct inode , struct inode ,
	281	void *, bool);
	282	/* keyinfo.c */
	283	extern int get_crypt_info(struct inode *);
	284	extern int fscrypt_get_encryption_info(struct inode *);
	285	extern void fscrypt_put_encryption_info(struct inode , struct fscrypt_info );
	286
	287	/* fname.c */
	288	extern int fscrypt_setup_filename(struct inode , const struct qstr ,
	289	int lookup, struct fscrypt_name *);
	290	extern void fscrypt_free_filename(struct fscrypt_name *);
	291	extern u32 fscrypt_fname_encrypted_size(struct inode *, u32);
	292	extern int fscrypt_fname_alloc_buffer(struct inode *, u32,
	293	struct fscrypt_str *);
	294	extern void fscrypt_fname_free_buffer(struct fscrypt_str *);
	295	extern int fscrypt_fname_disk_to_usr(struct inode *, u32, u32,
	296	const struct fscrypt_str , struct fscrypt_str );
	297	extern int fscrypt_fname_usr_to_disk(struct inode , const struct qstr ,
	298	struct fscrypt_str *);
	299	#endif
	300
	301	/* crypto.c */
b32e4482 JK	302	static inline struct fscrypt_ctx fscrypt_notsupp_get_ctx(struct inode i,
b32e4482 JK	303	gfp_t f)
0b81d077 JK	304	{
	305	return ERR_PTR(-EOPNOTSUPP);
	306	}
	307
	308	static inline void fscrypt_notsupp_release_ctx(struct fscrypt_ctx *c)
	309	{
	310	return;
	311	}
	312
	313	static inline struct page fscrypt_notsupp_encrypt_page(struct inode i,
b32e4482	314	struct page *p, gfp_t f)
0b81d077 JK	315	{
	316	return ERR_PTR(-EOPNOTSUPP);
	317	}
	318
	319	static inline int fscrypt_notsupp_decrypt_page(struct page *p)
	320	{
	321	return -EOPNOTSUPP;
	322	}
	323
	324	static inline void fscrypt_notsupp_decrypt_bio_pages(struct fscrypt_ctx *c,
	325	struct bio *b)
	326	{
	327	return;
	328	}
	329
	330	static inline void fscrypt_notsupp_pullback_bio_page(struct page **p, bool b)
	331	{
	332	return;
	333	}
	334
	335	static inline void fscrypt_notsupp_restore_control_page(struct page *p)
	336	{
	337	return;
	338	}
	339
	340	static inline int fscrypt_notsupp_zeroout_range(struct inode *i, pgoff_t p,
	341	sector_t s, unsigned int f)
	342	{
	343	return -EOPNOTSUPP;
	344	}
	345
	346	/* policy.c */
	347	static inline int fscrypt_notsupp_process_policy(struct inode *i,
	348	const struct fscrypt_policy *p)
	349	{
	350	return -EOPNOTSUPP;
	351	}
	352
	353	static inline int fscrypt_notsupp_get_policy(struct inode *i,
	354	struct fscrypt_policy *p)
	355	{
	356	return -EOPNOTSUPP;
	357	}
	358
	359	static inline int fscrypt_notsupp_has_permitted_context(struct inode *p,
	360	struct inode *i)
	361	{
	362	return 0;
	363	}
	364
	365	static inline int fscrypt_notsupp_inherit_context(struct inode *p,
	366	struct inode i, void v, bool b)
	367	{
	368	return -EOPNOTSUPP;
	369	}
	370
	371	/* keyinfo.c */
	372	static inline int fscrypt_notsupp_get_encryption_info(struct inode *i)
	373	{
	374	return -EOPNOTSUPP;
	375	}
	376
	377	static inline void fscrypt_notsupp_put_encryption_info(struct inode *i,
	378	struct fscrypt_info *f)
379	{
380	return;
381	}
382
383	/* fname.c */
384	static inline int fscrypt_notsupp_setup_filename(struct inode *dir,
385	const struct qstr *iname,
386	int lookup, struct fscrypt_name *fname)
387	{
388	if (dir->i_sb->s_cop->is_encrypted(dir))
389	return -EOPNOTSUPP;
390
391	memset(fname, 0, sizeof(struct fscrypt_name));
392	fname->usr_fname = iname;
393	fname->disk_name.name = (unsigned char *)iname->name;
394	fname->disk_name.len = iname->len;
395	return 0;
396	}
397
398	static inline void fscrypt_notsupp_free_filename(struct fscrypt_name *fname)
399	{
400	return;
401	}
402
403	static inline u32 fscrypt_notsupp_fname_encrypted_size(struct inode *i, u32 s)
404	{
405	/* never happens */
406	WARN_ON(1);
407	return 0;
408	}
409
410	static inline int fscrypt_notsupp_fname_alloc_buffer(struct inode *inode,
411	u32 ilen, struct fscrypt_str *crypto_str)
412	{
413	return -EOPNOTSUPP;
414	}
415
416	static inline void fscrypt_notsupp_fname_free_buffer(struct fscrypt_str *c)
417	{
418	return;
419	}
420
421	static inline int fscrypt_notsupp_fname_disk_to_usr(struct inode *inode,
422	u32 hash, u32 minor_hash,
423	const struct fscrypt_str *iname,
424	struct fscrypt_str *oname)
425	{
426	return -EOPNOTSUPP;
427	}
428
429	static inline int fscrypt_notsupp_fname_usr_to_disk(struct inode *inode,
430	const struct qstr *iname,
431	struct fscrypt_str *oname)
432	{
433	return -EOPNOTSUPP;
434	}
435	#endif /* _LINUX_FSCRYPTO_H */