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