[deliverable/linux.git] / fs / crypto / keyinfo.c

/*
 * key management facility for FS encryption support.
 *
 * Copyright (C) 2015, Google, Inc.
 *
 * This contains encryption key functions.
 *
 * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
 */

#include <keys/encrypted-type.h>
#include <keys/user-type.h>
#include <linux/random.h>
#include <linux/scatterlist.h>
#include <uapi/linux/keyctl.h>
#include <linux/fscrypto.h>

static void derive_crypt_complete(struct crypto_async_request *req, int rc)
{
	struct fscrypt_completion_result *ecr = req->data;

	if (rc == -EINPROGRESS)
		return;

	ecr->res = rc;
	complete(&ecr->completion);
}

/**
 * derive_key_aes() - Derive a key using AES-128-ECB
 * @deriving_key: Encryption key used for derivation.
 * @source_key:   Source key to which to apply derivation.
 * @derived_key:  Derived key.
 *
 * Return: Zero on success; non-zero otherwise.
 */
static int derive_key_aes(u8 deriving_key[FS_AES_128_ECB_KEY_SIZE],
				u8 source_key[FS_AES_256_XTS_KEY_SIZE],
				u8 derived_key[FS_AES_256_XTS_KEY_SIZE])
{
	int res = 0;
	struct skcipher_request *req = NULL;
	DECLARE_FS_COMPLETION_RESULT(ecr);
	struct scatterlist src_sg, dst_sg;
	struct crypto_skcipher *tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);

	if (IS_ERR(tfm)) {
		res = PTR_ERR(tfm);
		tfm = NULL;
		goto out;
	}
	crypto_skcipher_set_flags(tfm, CRYPTO_TFM_REQ_WEAK_KEY);
	req = skcipher_request_alloc(tfm, GFP_NOFS);
	if (!req) {
		res = -ENOMEM;
		goto out;
	}
	skcipher_request_set_callback(req,
			CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
			derive_crypt_complete, &ecr);
	res = crypto_skcipher_setkey(tfm, deriving_key,
					FS_AES_128_ECB_KEY_SIZE);
	if (res < 0)
		goto out;

	sg_init_one(&src_sg, source_key, FS_AES_256_XTS_KEY_SIZE);
	sg_init_one(&dst_sg, derived_key, FS_AES_256_XTS_KEY_SIZE);
	skcipher_request_set_crypt(req, &src_sg, &dst_sg,
					FS_AES_256_XTS_KEY_SIZE, NULL);
	res = crypto_skcipher_encrypt(req);
	if (res == -EINPROGRESS || res == -EBUSY) {
		wait_for_completion(&ecr.completion);
		res = ecr.res;
	}
out:
	skcipher_request_free(req);
	crypto_free_skcipher(tfm);
	return res;
}

static int validate_user_key(struct fscrypt_info *crypt_info,
			struct fscrypt_context *ctx, u8 *raw_key,
			u8 *prefix, int prefix_size)
{
	u8 *full_key_descriptor;
	struct key *keyring_key;
	struct fscrypt_key *master_key;
	const struct user_key_payload *ukp;
	int full_key_len = prefix_size + (FS_KEY_DESCRIPTOR_SIZE * 2) + 1;
	int res;

	full_key_descriptor = kmalloc(full_key_len, GFP_NOFS);
	if (!full_key_descriptor)
		return -ENOMEM;

	memcpy(full_key_descriptor, prefix, prefix_size);
	sprintf(full_key_descriptor + prefix_size,
			"%*phN", FS_KEY_DESCRIPTOR_SIZE,
			ctx->master_key_descriptor);
	full_key_descriptor[full_key_len - 1] = '\0';
	keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL);
	kfree(full_key_descriptor);
	if (IS_ERR(keyring_key))
		return PTR_ERR(keyring_key);

	if (keyring_key->type != &key_type_logon) {
		printk_once(KERN_WARNING
				"%s: key type must be logon\n", __func__);
		res = -ENOKEY;
		goto out;
	}
	down_read(&keyring_key->sem);
	ukp = user_key_payload(keyring_key);
	if (ukp->datalen != sizeof(struct fscrypt_key)) {
		res = -EINVAL;
		up_read(&keyring_key->sem);
		goto out;
	}
	master_key = (struct fscrypt_key *)ukp->data;
	BUILD_BUG_ON(FS_AES_128_ECB_KEY_SIZE != FS_KEY_DERIVATION_NONCE_SIZE);

	if (master_key->size != FS_AES_256_XTS_KEY_SIZE) {
		printk_once(KERN_WARNING
				"%s: key size incorrect: %d\n",
				__func__, master_key->size);
		res = -ENOKEY;
		up_read(&keyring_key->sem);
		goto out;
	}
	res = derive_key_aes(ctx->nonce, master_key->raw, raw_key);
	up_read(&keyring_key->sem);
	if (res)
		goto out;

	crypt_info->ci_keyring_key = keyring_key;
	return 0;
out:
	key_put(keyring_key);
	return res;
}

static void put_crypt_info(struct fscrypt_info *ci)
{
	if (!ci)
		return;

	key_put(ci->ci_keyring_key);
	crypto_free_skcipher(ci->ci_ctfm);
	kmem_cache_free(fscrypt_info_cachep, ci);
}

int get_crypt_info(struct inode *inode)
{
	struct fscrypt_info *crypt_info;
	struct fscrypt_context ctx;
	struct crypto_skcipher *ctfm;
	const char *cipher_str;
	u8 raw_key[FS_MAX_KEY_SIZE];
	u8 mode;
	int res;

	res = fscrypt_initialize();
	if (res)
		return res;

	if (!inode->i_sb->s_cop->get_context)
		return -EOPNOTSUPP;
retry:
	crypt_info = ACCESS_ONCE(inode->i_crypt_info);
	if (crypt_info) {
		if (!crypt_info->ci_keyring_key ||
				key_validate(crypt_info->ci_keyring_key) == 0)
			return 0;
		fscrypt_put_encryption_info(inode, crypt_info);
		goto retry;
	}

	res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
	if (res < 0) {
		if (!fscrypt_dummy_context_enabled(inode))
			return res;
		ctx.contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS;
		ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS;
		ctx.flags = 0;
	} else if (res != sizeof(ctx)) {
		return -EINVAL;
	}
	res = 0;

	crypt_info = kmem_cache_alloc(fscrypt_info_cachep, GFP_NOFS);
	if (!crypt_info)
		return -ENOMEM;

	crypt_info->ci_flags = ctx.flags;
	crypt_info->ci_data_mode = ctx.contents_encryption_mode;
	crypt_info->ci_filename_mode = ctx.filenames_encryption_mode;
	crypt_info->ci_ctfm = NULL;
	crypt_info->ci_keyring_key = NULL;
	memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor,
				sizeof(crypt_info->ci_master_key));
	if (S_ISREG(inode->i_mode))
		mode = crypt_info->ci_data_mode;
	else if (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))
		mode = crypt_info->ci_filename_mode;
	else
		BUG();

	switch (mode) {
	case FS_ENCRYPTION_MODE_AES_256_XTS:
		cipher_str = "xts(aes)";
		break;
	case FS_ENCRYPTION_MODE_AES_256_CTS:
		cipher_str = "cts(cbc(aes))";
		break;
	default:
		printk_once(KERN_WARNING
			    "%s: unsupported key mode %d (ino %u)\n",
			    __func__, mode, (unsigned) inode->i_ino);
		res = -ENOKEY;
		goto out;
	}
	if (fscrypt_dummy_context_enabled(inode)) {
		memset(raw_key, 0x42, FS_AES_256_XTS_KEY_SIZE);
		goto got_key;
	}

	res = validate_user_key(crypt_info, &ctx, raw_key,
			FS_KEY_DESC_PREFIX, FS_KEY_DESC_PREFIX_SIZE);
	if (res && inode->i_sb->s_cop->key_prefix) {
		u8 *prefix = NULL;
		int prefix_size, res2;

		prefix_size = inode->i_sb->s_cop->key_prefix(inode, &prefix);
		res2 = validate_user_key(crypt_info, &ctx, raw_key,
							prefix, prefix_size);
		if (res2) {
			if (res2 == -ENOKEY)
				res = -ENOKEY;
			goto out;
		}
	} else if (res) {
		goto out;
	}
got_key:
	ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
	if (!ctfm || IS_ERR(ctfm)) {
		res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
		printk(KERN_DEBUG
		       "%s: error %d (inode %u) allocating crypto tfm\n",
		       __func__, res, (unsigned) inode->i_ino);
		goto out;
	}
	crypt_info->ci_ctfm = ctfm;
	crypto_skcipher_clear_flags(ctfm, ~0);
	crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_REQ_WEAK_KEY);
	res = crypto_skcipher_setkey(ctfm, raw_key, fscrypt_key_size(mode));
	if (res)
		goto out;

	memzero_explicit(raw_key, sizeof(raw_key));
	if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) != NULL) {
		put_crypt_info(crypt_info);
		goto retry;
	}
	return 0;

out:
	if (res == -ENOKEY)
		res = 0;
	put_crypt_info(crypt_info);
	memzero_explicit(raw_key, sizeof(raw_key));
	return res;
}

void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci)
{
	struct fscrypt_info *prev;

	if (ci == NULL)
		ci = ACCESS_ONCE(inode->i_crypt_info);
	if (ci == NULL)
		return;

	prev = cmpxchg(&inode->i_crypt_info, ci, NULL);
	if (prev != ci)
		return;

	put_crypt_info(ci);
}
EXPORT_SYMBOL(fscrypt_put_encryption_info);

int fscrypt_get_encryption_info(struct inode *inode)
{
	struct fscrypt_info *ci = inode->i_crypt_info;

	if (!ci ||
		(ci->ci_keyring_key &&
		 (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
					       (1 << KEY_FLAG_REVOKED) |
					       (1 << KEY_FLAG_DEAD)))))
		return get_crypt_info(inode);
	return 0;
}
EXPORT_SYMBOL(fscrypt_get_encryption_info);
Commit	Line	Data
0adda907	1	/*
0b81d077	2	* key management facility for FS encryption support.
0adda907 JK	3	*
	4	* Copyright (C) 2015, Google, Inc.
	5	*
0b81d077	6	* This contains encryption key functions.
0adda907 JK	7	*
	8	* Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
	9	*/
0b81d077	10
0adda907 JK	11	#include <keys/encrypted-type.h>
	12	#include <keys/user-type.h>
	13	#include <linux/random.h>
	14	#include <linux/scatterlist.h>
	15	#include <uapi/linux/keyctl.h>
0b81d077	16	#include <linux/fscrypto.h>
0adda907 JK	17
	18	static void derive_crypt_complete(struct crypto_async_request *req, int rc)
	19	{
0b81d077	20	struct fscrypt_completion_result *ecr = req->data;
0adda907 JK	21
	22	if (rc == -EINPROGRESS)
	23	return;
	24
	25	ecr->res = rc;
	26	complete(&ecr->completion);
	27	}
	28
	29	/**
0b81d077	30	* derive_key_aes() - Derive a key using AES-128-ECB
0fac2d50	31	* @deriving_key: Encryption key used for derivation.
0adda907 JK	32	* @source_key: Source key to which to apply derivation.
	33	* @derived_key: Derived key.
	34	*
	35	* Return: Zero on success; non-zero otherwise.
	36	*/
0b81d077 JK	37	static int derive_key_aes(u8 deriving_key[FS_AES_128_ECB_KEY_SIZE],
	38	u8 source_key[FS_AES_256_XTS_KEY_SIZE],
	39	u8 derived_key[FS_AES_256_XTS_KEY_SIZE])
0adda907 JK	40	{
0adda907 JK	41	int res = 0;
d407574e	42	struct skcipher_request *req = NULL;
0b81d077	43	DECLARE_FS_COMPLETION_RESULT(ecr);
0adda907	44	struct scatterlist src_sg, dst_sg;
d407574e	45	struct crypto_skcipher *tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
0adda907 JK	46
	47	if (IS_ERR(tfm)) {
	48	res = PTR_ERR(tfm);
	49	tfm = NULL;
	50	goto out;
	51	}
d407574e LT	52	crypto_skcipher_set_flags(tfm, CRYPTO_TFM_REQ_WEAK_KEY);
d407574e LT	53	req = skcipher_request_alloc(tfm, GFP_NOFS);
0adda907 JK	54	if (!req) {
	55	res = -ENOMEM;
	56	goto out;
	57	}
d407574e	58	skcipher_request_set_callback(req,
0adda907 JK	59	CRYPTO_TFM_REQ_MAY_BACKLOG \| CRYPTO_TFM_REQ_MAY_SLEEP,
0adda907 JK	60	derive_crypt_complete, &ecr);
d407574e	61	res = crypto_skcipher_setkey(tfm, deriving_key,
0b81d077	62	FS_AES_128_ECB_KEY_SIZE);
0adda907 JK	63	if (res < 0)
	64	goto out;
	65
0b81d077 JK	66	sg_init_one(&src_sg, source_key, FS_AES_256_XTS_KEY_SIZE);
0b81d077 JK	67	sg_init_one(&dst_sg, derived_key, FS_AES_256_XTS_KEY_SIZE);
d407574e	68	skcipher_request_set_crypt(req, &src_sg, &dst_sg,
0b81d077	69	FS_AES_256_XTS_KEY_SIZE, NULL);
d407574e	70	res = crypto_skcipher_encrypt(req);
0adda907	71	if (res == -EINPROGRESS \|\| res == -EBUSY) {
0adda907 JK	72	wait_for_completion(&ecr.completion);
	73	res = ecr.res;
	74	}
	75	out:
d407574e LT	76	skcipher_request_free(req);
d407574e LT	77	crypto_free_skcipher(tfm);
0adda907 JK	78	return res;
	79	}
	80
b5a7aef1 JK	81	static int validate_user_key(struct fscrypt_info *crypt_info,
	82	struct fscrypt_context ctx, u8 raw_key,
	83	u8 *prefix, int prefix_size)
	84	{
	85	u8 *full_key_descriptor;
	86	struct key *keyring_key;
	87	struct fscrypt_key *master_key;
	88	const struct user_key_payload *ukp;
	89	int full_key_len = prefix_size + (FS_KEY_DESCRIPTOR_SIZE * 2) + 1;
	90	int res;
	91
	92	full_key_descriptor = kmalloc(full_key_len, GFP_NOFS);
	93	if (!full_key_descriptor)
	94	return -ENOMEM;
	95
	96	memcpy(full_key_descriptor, prefix, prefix_size);
	97	sprintf(full_key_descriptor + prefix_size,
	98	"%*phN", FS_KEY_DESCRIPTOR_SIZE,
	99	ctx->master_key_descriptor);
	100	full_key_descriptor[full_key_len - 1] = '\0';
	101	keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL);
	102	kfree(full_key_descriptor);
	103	if (IS_ERR(keyring_key))
	104	return PTR_ERR(keyring_key);
	105
	106	if (keyring_key->type != &key_type_logon) {
	107	printk_once(KERN_WARNING
	108	"%s: key type must be logon\n", __func__);
	109	res = -ENOKEY;
	110	goto out;
	111	}
	112	down_read(&keyring_key->sem);
	113	ukp = user_key_payload(keyring_key);
	114	if (ukp->datalen != sizeof(struct fscrypt_key)) {
	115	res = -EINVAL;
	116	up_read(&keyring_key->sem);
	117	goto out;
	118	}
	119	master_key = (struct fscrypt_key *)ukp->data;
	120	BUILD_BUG_ON(FS_AES_128_ECB_KEY_SIZE != FS_KEY_DERIVATION_NONCE_SIZE);
	121
	122	if (master_key->size != FS_AES_256_XTS_KEY_SIZE) {
	123	printk_once(KERN_WARNING
	124	"%s: key size incorrect: %d\n",
	125	__func__, master_key->size);
	126	res = -ENOKEY;
	127	up_read(&keyring_key->sem);
	128	goto out;
	129	}
	130	res = derive_key_aes(ctx->nonce, master_key->raw, raw_key);
	131	up_read(&keyring_key->sem);
	132	if (res)
	133	goto out;
	134
	135	crypt_info->ci_keyring_key = keyring_key;
	136	return 0;
	137	out:
	138	key_put(keyring_key);
	139	return res;
	140	}
	141
0b81d077	142	static void put_crypt_info(struct fscrypt_info *ci)
0adda907	143	{
0adda907 JK	144	if (!ci)
	145	return;
	146
d407574e LT	147	key_put(ci->ci_keyring_key);
d407574e LT	148	crypto_free_skcipher(ci->ci_ctfm);
0b81d077	149	kmem_cache_free(fscrypt_info_cachep, ci);
0adda907 JK	150	}
0adda907 JK	151
0b81d077	152	int get_crypt_info(struct inode *inode)
0adda907	153	{
0b81d077	154	struct fscrypt_info *crypt_info;
0b81d077	155	struct fscrypt_context ctx;
d407574e	156	struct crypto_skcipher *ctfm;
26bf3dc7	157	const char *cipher_str;
0b81d077 JK	158	u8 raw_key[FS_MAX_KEY_SIZE];
0b81d077 JK	159	u8 mode;
0adda907 JK	160	int res;
0adda907 JK	161
0b81d077	162	res = fscrypt_initialize();
cfc4d971 JK	163	if (res)
cfc4d971 JK	164	return res;
0b81d077 JK	165
	166	if (!inode->i_sb->s_cop->get_context)
	167	return -EOPNOTSUPP;
26bf3dc7	168	retry:
0b81d077	169	crypt_info = ACCESS_ONCE(inode->i_crypt_info);
26bf3dc7 JK	170	if (crypt_info) {
	171	if (!crypt_info->ci_keyring_key \|\|
	172	key_validate(crypt_info->ci_keyring_key) == 0)
0adda907	173	return 0;
0b81d077	174	fscrypt_put_encryption_info(inode, crypt_info);
26bf3dc7	175	goto retry;
0adda907 JK	176	}
0adda907 JK	177
0b81d077 JK	178	res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
	179	if (res < 0) {
	180	if (!fscrypt_dummy_context_enabled(inode))
	181	return res;
	182	ctx.contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS;
	183	ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS;
	184	ctx.flags = 0;
	185	} else if (res != sizeof(ctx)) {
0adda907	186	return -EINVAL;
0b81d077	187	}
0adda907 JK	188	res = 0;
0adda907 JK	189
0b81d077	190	crypt_info = kmem_cache_alloc(fscrypt_info_cachep, GFP_NOFS);
0adda907 JK	191	if (!crypt_info)
	192	return -ENOMEM;
	193
	194	crypt_info->ci_flags = ctx.flags;
	195	crypt_info->ci_data_mode = ctx.contents_encryption_mode;
	196	crypt_info->ci_filename_mode = ctx.filenames_encryption_mode;
	197	crypt_info->ci_ctfm = NULL;
26bf3dc7	198	crypt_info->ci_keyring_key = NULL;
0adda907 JK	199	memcpy(crypt_info->ci_master_key, ctx.master_key_descriptor,
	200	sizeof(crypt_info->ci_master_key));
	201	if (S_ISREG(inode->i_mode))
26bf3dc7	202	mode = crypt_info->ci_data_mode;
0adda907	203	else if (S_ISDIR(inode->i_mode) \|\| S_ISLNK(inode->i_mode))
26bf3dc7	204	mode = crypt_info->ci_filename_mode;
640778fb	205	else
0adda907	206	BUG();
640778fb	207
26bf3dc7	208	switch (mode) {
0b81d077	209	case FS_ENCRYPTION_MODE_AES_256_XTS:
26bf3dc7 JK	210	cipher_str = "xts(aes)";
26bf3dc7 JK	211	break;
0b81d077	212	case FS_ENCRYPTION_MODE_AES_256_CTS:
26bf3dc7 JK	213	cipher_str = "cts(cbc(aes))";
	214	break;
	215	default:
	216	printk_once(KERN_WARNING
0b81d077 JK	217	"%s: unsupported key mode %d (ino %u)\n",
0b81d077 JK	218	__func__, mode, (unsigned) inode->i_ino);
26bf3dc7 JK	219	res = -ENOKEY;
	220	goto out;
	221	}
0b81d077 JK	222	if (fscrypt_dummy_context_enabled(inode)) {
	223	memset(raw_key, 0x42, FS_AES_256_XTS_KEY_SIZE);
	224	goto got_key;
	225	}
0b81d077	226
b5a7aef1 JK	227	res = validate_user_key(crypt_info, &ctx, raw_key,
	228	FS_KEY_DESC_PREFIX, FS_KEY_DESC_PREFIX_SIZE);
	229	if (res && inode->i_sb->s_cop->key_prefix) {
	230	u8 *prefix = NULL;
	231	int prefix_size, res2;
	232
	233	prefix_size = inode->i_sb->s_cop->key_prefix(inode, &prefix);
	234	res2 = validate_user_key(crypt_info, &ctx, raw_key,
	235	prefix, prefix_size);
	236	if (res2) {
	237	if (res2 == -ENOKEY)
	238	res = -ENOKEY;
	239	goto out;
	240	}
	241	} else if (res) {
66aa3e12 JK	242	goto out;
66aa3e12 JK	243	}
0b81d077	244	got_key:
d407574e	245	ctfm = crypto_alloc_skcipher(cipher_str, 0, 0);
26bf3dc7 JK	246	if (!ctfm \|\| IS_ERR(ctfm)) {
	247	res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
	248	printk(KERN_DEBUG
	249	"%s: error %d (inode %u) allocating crypto tfm\n",
	250	__func__, res, (unsigned) inode->i_ino);
	251	goto out;
0adda907	252	}
26bf3dc7	253	crypt_info->ci_ctfm = ctfm;
d407574e LT	254	crypto_skcipher_clear_flags(ctfm, ~0);
	255	crypto_skcipher_set_flags(ctfm, CRYPTO_TFM_REQ_WEAK_KEY);
	256	res = crypto_skcipher_setkey(ctfm, raw_key, fscrypt_key_size(mode));
26bf3dc7 JK	257	if (res)
	258	goto out;
	259
	260	memzero_explicit(raw_key, sizeof(raw_key));
0b81d077 JK	261	if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) != NULL) {
0b81d077 JK	262	put_crypt_info(crypt_info);
26bf3dc7 JK	263	goto retry;
	264	}
	265	return 0;
	266
	267	out:
0b81d077	268	if (res == -ENOKEY)
26bf3dc7	269	res = 0;
0b81d077	270	put_crypt_info(crypt_info);
26bf3dc7	271	memzero_explicit(raw_key, sizeof(raw_key));
0adda907 JK	272	return res;
	273	}
	274
0b81d077	275	void fscrypt_put_encryption_info(struct inode inode, struct fscrypt_info ci)
0adda907	276	{
0b81d077 JK	277	struct fscrypt_info *prev;
	278
	279	if (ci == NULL)
	280	ci = ACCESS_ONCE(inode->i_crypt_info);
	281	if (ci == NULL)
	282	return;
0adda907	283
0b81d077 JK	284	prev = cmpxchg(&inode->i_crypt_info, ci, NULL);
	285	if (prev != ci)
	286	return;
	287
	288	put_crypt_info(ci);
	289	}
	290	EXPORT_SYMBOL(fscrypt_put_encryption_info);
	291
	292	int fscrypt_get_encryption_info(struct inode *inode)
	293	{
	294	struct fscrypt_info *ci = inode->i_crypt_info;
	295
	296	if (!ci \|\|
	297	(ci->ci_keyring_key &&
	298	(ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) \|
	299	(1 << KEY_FLAG_REVOKED) \|
	300	(1 << KEY_FLAG_DEAD)))))
	301	return get_crypt_info(inode);
	302	return 0;
0adda907	303	}
0b81d077	304	EXPORT_SYMBOL(fscrypt_get_encryption_info);