[mirror_ubuntu-artful-kernel.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 }

#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)

/*
 * fscrypt superblock flags
 */
#define FS_CFLG_INPLACE_ENCRYPTION (1U << 1)

/*
 * crypto opertions for filesystems
 */
struct fscrypt_operations {
	unsigned int flags;
	int (*get_context)(struct inode *, void *, size_t);
	int (*key_prefix)(struct inode *, u8 **);
	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 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 *,
						unsigned int, unsigned int,
						gfp_t);
extern int fscrypt_decrypt_page(struct inode *, struct page *, unsigned int,
				unsigned int);
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 file *, 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,
						unsigned int len,
						unsigned int offs,
						gfp_t f)
{
	return ERR_PTR(-EOPNOTSUPP);
}

static inline int fscrypt_notsupp_decrypt_page(struct inode *i, struct page *p,
						unsigned int len, unsigned int offs)
{
	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 file *f,
				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
0b81d077 JK	114	#define FS_FNAME_NUM_SCATTER_ENTRIES 4
	115	#define FS_CRYPTO_BLOCK_SIZE 16
	116	#define FS_FNAME_CRYPTO_DIGEST_SIZE 32
	117
	118	/**
	119	* For encrypted symlinks, the ciphertext length is stored at the beginning
	120	* of the string in little-endian format.
	121	*/
	122	struct fscrypt_symlink_data {
	123	__le16 len;
	124	char encrypted_path[1];
	125	} __packed;
	126
	127	/**
	128	* This function is used to calculate the disk space required to
	129	* store a filename of length l in encrypted symlink format.
	130	*/
	131	static inline u32 fscrypt_symlink_data_len(u32 l)
	132	{
	133	if (l < FS_CRYPTO_BLOCK_SIZE)
	134	l = FS_CRYPTO_BLOCK_SIZE;
	135	return (l + sizeof(struct fscrypt_symlink_data) - 1);
	136	}
	137
	138	struct fscrypt_str {
	139	unsigned char *name;
	140	u32 len;
	141	};
	142
	143	struct fscrypt_name {
	144	const struct qstr *usr_fname;
	145	struct fscrypt_str disk_name;
	146	u32 hash;
	147	u32 minor_hash;
	148	struct fscrypt_str crypto_buf;
	149	};
	150
	151	#define FSTR_INIT(n, l) { .name = n, .len = l }
	152	#define FSTR_TO_QSTR(f) QSTR_INIT((f)->name, (f)->len)
	153	#define fname_name(p) ((p)->disk_name.name)
	154	#define fname_len(p) ((p)->disk_name.len)
	155
1c7dcf69 DG	156	/*
	157	* fscrypt superblock flags
	158	*/
	159	#define FS_CFLG_INPLACE_ENCRYPTION (1U << 1)
	160
0b81d077 JK	161	/*
	162	* crypto opertions for filesystems
	163	*/
	164	struct fscrypt_operations {
1c7dcf69	165	unsigned int flags;
0b81d077	166	int (get_context)(struct inode , void *, size_t);
b5a7aef1	167	int (key_prefix)(struct inode , u8 **);
0b81d077 JK	168	int (prepare_context)(struct inode );
	169	int (set_context)(struct inode , const void , size_t, void );
	170	int (dummy_context)(struct inode );
	171	bool (is_encrypted)(struct inode );
	172	bool (empty_dir)(struct inode );
	173	unsigned (max_namelen)(struct inode );
	174	};
	175
	176	static inline bool fscrypt_dummy_context_enabled(struct inode *inode)
	177	{
	178	if (inode->i_sb->s_cop->dummy_context &&
	179	inode->i_sb->s_cop->dummy_context(inode))
	180	return true;
	181	return false;
	182	}
	183
	184	static inline bool fscrypt_valid_contents_enc_mode(u32 mode)
	185	{
	186	return (mode == FS_ENCRYPTION_MODE_AES_256_XTS);
	187	}
	188
	189	static inline bool fscrypt_valid_filenames_enc_mode(u32 mode)
	190	{
	191	return (mode == FS_ENCRYPTION_MODE_AES_256_CTS);
	192	}
	193
0b81d077 JK	194	static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
	195	{
	196	if (str->len == 1 && str->name[0] == '.')
	197	return true;
	198
	199	if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
	200	return true;
	201
	202	return false;
	203	}
	204
	205	static inline struct page fscrypt_control_page(struct page page)
	206	{
	207	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	208	return ((struct fscrypt_ctx *)page_private(page))->w.control_page;
	209	#else
	210	WARN_ON_ONCE(1);
	211	return ERR_PTR(-EINVAL);
	212	#endif
	213	}
	214
	215	static inline int fscrypt_has_encryption_key(struct inode *inode)
	216	{
	217	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	218	return (inode->i_crypt_info != NULL);
	219	#else
	220	return 0;
	221	#endif
	222	}
	223
	224	static inline void fscrypt_set_encrypted_dentry(struct dentry *dentry)
	225	{
	226	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	227	spin_lock(&dentry->d_lock);
	228	dentry->d_flags \|= DCACHE_ENCRYPTED_WITH_KEY;
	229	spin_unlock(&dentry->d_lock);
	230	#endif
	231	}
	232
	233	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	234	extern const struct dentry_operations fscrypt_d_ops;
	235	#endif
	236
	237	static inline void fscrypt_set_d_op(struct dentry *dentry)
	238	{
	239	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	240	d_set_d_op(dentry, &fscrypt_d_ops);
	241	#endif
	242	}
	243
	244	#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
	245	/* crypto.c */
	246	extern struct kmem_cache *fscrypt_info_cachep;
	247	int fscrypt_initialize(void);
	248
b32e4482	249	extern struct fscrypt_ctx fscrypt_get_ctx(struct inode , gfp_t);
0b81d077	250	extern void fscrypt_release_ctx(struct fscrypt_ctx *);
7821d4dd DG	251	extern struct page fscrypt_encrypt_page(struct inode , struct page *,
	252	unsigned int, unsigned int,
	253	gfp_t);
	254	extern int fscrypt_decrypt_page(struct inode , struct page , unsigned int,
	255	unsigned int);
0b81d077 JK	256	extern void fscrypt_decrypt_bio_pages(struct fscrypt_ctx , struct bio );
	257	extern void fscrypt_pullback_bio_page(struct page **, bool);
	258	extern void fscrypt_restore_control_page(struct page *);
	259	extern int fscrypt_zeroout_range(struct inode *, pgoff_t, sector_t,
	260	unsigned int);
	261	/* policy.c */
ba63f23d	262	extern int fscrypt_process_policy(struct file , const struct fscrypt_policy );
0b81d077 JK	263	extern int fscrypt_get_policy(struct inode , struct fscrypt_policy );
	264	extern int fscrypt_has_permitted_context(struct inode , struct inode );
	265	extern int fscrypt_inherit_context(struct inode , struct inode ,
	266	void *, bool);
	267	/* keyinfo.c */
	268	extern int get_crypt_info(struct inode *);
	269	extern int fscrypt_get_encryption_info(struct inode *);
	270	extern void fscrypt_put_encryption_info(struct inode , struct fscrypt_info );
	271
	272	/* fname.c */
	273	extern int fscrypt_setup_filename(struct inode , const struct qstr ,
	274	int lookup, struct fscrypt_name *);
	275	extern void fscrypt_free_filename(struct fscrypt_name *);
	276	extern u32 fscrypt_fname_encrypted_size(struct inode *, u32);
	277	extern int fscrypt_fname_alloc_buffer(struct inode *, u32,
	278	struct fscrypt_str *);
	279	extern void fscrypt_fname_free_buffer(struct fscrypt_str *);
	280	extern int fscrypt_fname_disk_to_usr(struct inode *, u32, u32,
	281	const struct fscrypt_str , struct fscrypt_str );
	282	extern int fscrypt_fname_usr_to_disk(struct inode , const struct qstr ,
	283	struct fscrypt_str *);
	284	#endif
	285
	286	/* crypto.c */
b32e4482 JK	287	static inline struct fscrypt_ctx fscrypt_notsupp_get_ctx(struct inode i,
b32e4482 JK	288	gfp_t f)
0b81d077 JK	289	{
	290	return ERR_PTR(-EOPNOTSUPP);
	291	}
	292
	293	static inline void fscrypt_notsupp_release_ctx(struct fscrypt_ctx *c)
	294	{
	295	return;
	296	}
	297
	298	static inline struct page fscrypt_notsupp_encrypt_page(struct inode i,
7821d4dd DG	299	struct page *p,
	300	unsigned int len,
	301	unsigned int offs,
	302	gfp_t f)
0b81d077 JK	303	{
	304	return ERR_PTR(-EOPNOTSUPP);
	305	}
	306
7821d4dd DG	307	static inline int fscrypt_notsupp_decrypt_page(struct inode i, struct page p,
7821d4dd DG	308	unsigned int len, unsigned int offs)
0b81d077 JK	309	{
	310	return -EOPNOTSUPP;
	311	}
	312
	313	static inline void fscrypt_notsupp_decrypt_bio_pages(struct fscrypt_ctx *c,
	314	struct bio *b)
	315	{
	316	return;
	317	}
	318
	319	static inline void fscrypt_notsupp_pullback_bio_page(struct page **p, bool b)
	320	{
	321	return;
	322	}
	323
	324	static inline void fscrypt_notsupp_restore_control_page(struct page *p)
	325	{
	326	return;
	327	}
	328
	329	static inline int fscrypt_notsupp_zeroout_range(struct inode *i, pgoff_t p,
	330	sector_t s, unsigned int f)
	331	{
	332	return -EOPNOTSUPP;
	333	}
	334
	335	/* policy.c */
ba63f23d	336	static inline int fscrypt_notsupp_process_policy(struct file *f,
0b81d077 JK	337	const struct fscrypt_policy *p)
	338	{
	339	return -EOPNOTSUPP;
	340	}
	341
	342	static inline int fscrypt_notsupp_get_policy(struct inode *i,
	343	struct fscrypt_policy *p)
	344	{
	345	return -EOPNOTSUPP;
	346	}
	347
	348	static inline int fscrypt_notsupp_has_permitted_context(struct inode *p,
	349	struct inode *i)
	350	{
	351	return 0;
	352	}
	353
	354	static inline int fscrypt_notsupp_inherit_context(struct inode *p,
	355	struct inode i, void v, bool b)
	356	{
	357	return -EOPNOTSUPP;
	358	}
	359
	360	/* keyinfo.c */
	361	static inline int fscrypt_notsupp_get_encryption_info(struct inode *i)
	362	{
	363	return -EOPNOTSUPP;
	364	}
	365
	366	static inline void fscrypt_notsupp_put_encryption_info(struct inode *i,
	367	struct fscrypt_info *f)
	368	{
	369	return;
	370	}
	371
	372	/* fname.c */
	373	static inline int fscrypt_notsupp_setup_filename(struct inode *dir,
	374	const struct qstr *iname,
	375	int lookup, struct fscrypt_name *fname)
	376	{
	377	if (dir->i_sb->s_cop->is_encrypted(dir))
	378	return -EOPNOTSUPP;
	379
	380	memset(fname, 0, sizeof(struct fscrypt_name));
	381	fname->usr_fname = iname;
	382	fname->disk_name.name = (unsigned char *)iname->name;
	383	fname->disk_name.len = iname->len;
	384	return 0;
	385	}
	386
	387	static inline void fscrypt_notsupp_free_filename(struct fscrypt_name *fname)
	388	{
	389	return;
	390	}
	391
	392	static inline u32 fscrypt_notsupp_fname_encrypted_size(struct inode *i, u32 s)
	393	{
	394	/* never happens */
	395	WARN_ON(1);
	396	return 0;
	397	}
	398
	399	static inline int fscrypt_notsupp_fname_alloc_buffer(struct inode *inode,
	400	u32 ilen, struct fscrypt_str *crypto_str)
401	{
402	return -EOPNOTSUPP;
403	}
404
405	static inline void fscrypt_notsupp_fname_free_buffer(struct fscrypt_str *c)
406	{
407	return;
408	}
409
410	static inline int fscrypt_notsupp_fname_disk_to_usr(struct inode *inode,
411	u32 hash, u32 minor_hash,
412	const struct fscrypt_str *iname,
413	struct fscrypt_str *oname)
414	{
415	return -EOPNOTSUPP;
416	}
417
418	static inline int fscrypt_notsupp_fname_usr_to_disk(struct inode *inode,
419	const struct qstr *iname,
420	struct fscrypt_str *oname)
421	{
422	return -EOPNOTSUPP;
423	}
424	#endif /* _LINUX_FSCRYPTO_H */