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fs crypto: move per-file encryption from f2fs tree to fs/crypto

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This patch adds the renamed functions moved from the f2fs crypto files.

1. definitions for per-file encryption used by ext4 and f2fs.

2. crypto.c for encrypt/decrypt functions
 a. IO preparation:
  - fscrypt_get_ctx / fscrypt_release_ctx
 b. before IOs:
  - fscrypt_encrypt_page
  - fscrypt_decrypt_page
  - fscrypt_zeroout_range
 c. after IOs:
  - fscrypt_decrypt_bio_pages
  - fscrypt_pullback_bio_page
  - fscrypt_restore_control_page

3. policy.c supporting context management.
 a. For ioctls:
  - fscrypt_process_policy
  - fscrypt_get_policy
 b. For context permission
  - fscrypt_has_permitted_context
  - fscrypt_inherit_context

4. keyinfo.c to handle permissions
  - fscrypt_get_encryption_info
  - fscrypt_free_encryption_info

5. fname.c to support filename encryption
 a. general wrapper functions
  - fscrypt_fname_disk_to_usr
  - fscrypt_fname_usr_to_disk
  - fscrypt_setup_filename
  - fscrypt_free_filename

 b. specific filename handling functions
  - fscrypt_fname_alloc_buffer
  - fscrypt_fname_free_buffer

6. Makefile and Kconfig

Cc: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Uday Savagaonkar <savagaon@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Jaegeuk Kim 2015-05-15 16:26:10 -07:00
parent 59692b7c71
commit 0b81d07790
25 changed files with 1634 additions and 1323 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
fs/Kconfig
View File

@ -84,6 +84,8 @@ config MANDATORY_FILE_LOCKING
To the best of my knowledge this is dead code that no one cares about.
source "fs/crypto/Kconfig"
source "fs/notify/Kconfig"
source "fs/quota/Kconfig"

1
fs/Makefile
View File

@ -30,6 +30,7 @@ obj-$(CONFIG_EVENTFD) += eventfd.o
obj-$(CONFIG_USERFAULTFD) += userfaultfd.o
obj-$(CONFIG_AIO) += aio.o
obj-$(CONFIG_FS_DAX) += dax.o
obj-$(CONFIG_FS_ENCRYPTION) += crypto/
obj-$(CONFIG_FILE_LOCKING) += locks.o
obj-$(CONFIG_COMPAT) += compat.o compat_ioctl.o
obj-$(CONFIG_BINFMT_AOUT) += binfmt_aout.o

18
fs/crypto/Kconfig Normal file
View File

@ -0,0 +1,18 @@
config FS_ENCRYPTION
tristate "FS Encryption (Per-file encryption)"
depends on BLOCK
select CRYPTO
select CRYPTO_AES
select CRYPTO_CBC
select CRYPTO_ECB
select CRYPTO_XTS
select CRYPTO_CTS
select CRYPTO_CTR
select CRYPTO_SHA256
select KEYS
select ENCRYPTED_KEYS
help
Enable encryption of files and directories. This
feature is similar to ecryptfs, but it is more memory
efficient since it avoids caching the encrypted and
decrypted pages in the page cache.

3
fs/crypto/Makefile Normal file
View File

@ -0,0 +1,3 @@
obj-$(CONFIG_FS_ENCRYPTION) += fscrypto.o
fscrypto-y := crypto.o fname.o policy.o keyinfo.o

556
fs/crypto/crypto.c Normal file
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@ -0,0 +1,556 @@
/*
* This contains encryption functions for per-file encryption.
*
* Copyright (C) 2015, Google, Inc.
* Copyright (C) 2015, Motorola Mobility
*
* Written by Michael Halcrow, 2014.
*
* Filename encryption additions
* Uday Savagaonkar, 2014
* Encryption policy handling additions
* Ildar Muslukhov, 2014
* Add fscrypt_pullback_bio_page()
* Jaegeuk Kim, 2015.
*
* This has not yet undergone a rigorous security audit.
*
* The usage of AES-XTS should conform to recommendations in NIST
* Special Publication 800-38E and IEEE P1619/D16.
*/
#include <linux/crypto.h>
#include <linux/ecryptfs.h>
#include <linux/pagemap.h>
#include <linux/mempool.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/ratelimit.h>
#include <linux/bio.h>
#include <linux/dcache.h>
#include <linux/fscrypto.h>
static unsigned int num_prealloc_crypto_pages = 32;
static unsigned int num_prealloc_crypto_ctxs = 128;
module_param(num_prealloc_crypto_pages, uint, 0444);
MODULE_PARM_DESC(num_prealloc_crypto_pages,
"Number of crypto pages to preallocate");
module_param(num_prealloc_crypto_ctxs, uint, 0444);
MODULE_PARM_DESC(num_prealloc_crypto_ctxs,
"Number of crypto contexts to preallocate");
static mempool_t *fscrypt_bounce_page_pool = NULL;
static LIST_HEAD(fscrypt_free_ctxs);
static DEFINE_SPINLOCK(fscrypt_ctx_lock);
static struct workqueue_struct *fscrypt_read_workqueue;
static DEFINE_MUTEX(fscrypt_init_mutex);
static struct kmem_cache *fscrypt_ctx_cachep;
struct kmem_cache *fscrypt_info_cachep;
/**
* fscrypt_release_ctx() - Releases an encryption context
* @ctx: The encryption context to release.
*
* If the encryption context was allocated from the pre-allocated pool, returns
* it to that pool. Else, frees it.
*
* If there's a bounce page in the context, this frees that.
*/
void fscrypt_release_ctx(struct fscrypt_ctx *ctx)
{
unsigned long flags;
if (ctx->flags & FS_WRITE_PATH_FL && ctx->w.bounce_page) {
mempool_free(ctx->w.bounce_page, fscrypt_bounce_page_pool);
ctx->w.bounce_page = NULL;
}
ctx->w.control_page = NULL;
if (ctx->flags & FS_CTX_REQUIRES_FREE_ENCRYPT_FL) {
kmem_cache_free(fscrypt_ctx_cachep, ctx);
} else {
spin_lock_irqsave(&fscrypt_ctx_lock, flags);
list_add(&ctx->free_list, &fscrypt_free_ctxs);
spin_unlock_irqrestore(&fscrypt_ctx_lock, flags);
}
}
EXPORT_SYMBOL(fscrypt_release_ctx);
/**
* fscrypt_get_ctx() - Gets an encryption context
* @inode: The inode for which we are doing the crypto
*
* Allocates and initializes an encryption context.
*
* Return: An allocated and initialized encryption context on success; error
* value or NULL otherwise.
*/
struct fscrypt_ctx *fscrypt_get_ctx(struct inode *inode)
{
struct fscrypt_ctx *ctx = NULL;
struct fscrypt_info *ci = inode->i_crypt_info;
unsigned long flags;
if (ci == NULL)
return ERR_PTR(-ENOKEY);
/*
* We first try getting the ctx from a free list because in
* the common case the ctx will have an allocated and
* initialized crypto tfm, so it's probably a worthwhile
* optimization. For the bounce page, we first try getting it
* from the kernel allocator because that's just about as fast
* as getting it from a list and because a cache of free pages
* should generally be a "last resort" option for a filesystem
* to be able to do its job.
*/
spin_lock_irqsave(&fscrypt_ctx_lock, flags);
ctx = list_first_entry_or_null(&fscrypt_free_ctxs,
struct fscrypt_ctx, free_list);
if (ctx)
list_del(&ctx->free_list);
spin_unlock_irqrestore(&fscrypt_ctx_lock, flags);
if (!ctx) {
ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, GFP_NOFS);
if (!ctx)
return ERR_PTR(-ENOMEM);
ctx->flags |= FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
} else {
ctx->flags &= ~FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
}
ctx->flags &= ~FS_WRITE_PATH_FL;
return ctx;
}
EXPORT_SYMBOL(fscrypt_get_ctx);
/**
* fscrypt_complete() - The completion callback for page encryption
* @req: The asynchronous encryption request context
* @res: The result of the encryption operation
*/
static void fscrypt_complete(struct crypto_async_request *req, int res)
{
struct fscrypt_completion_result *ecr = req->data;
if (res == -EINPROGRESS)
return;
ecr->res = res;
complete(&ecr->completion);
}
typedef enum {
FS_DECRYPT = 0,
FS_ENCRYPT,
} fscrypt_direction_t;
static int do_page_crypto(struct inode *inode,
fscrypt_direction_t rw, pgoff_t index,
struct page *src_page, struct page *dest_page)
{
u8 xts_tweak[FS_XTS_TWEAK_SIZE];
struct ablkcipher_request *req = NULL;
DECLARE_FS_COMPLETION_RESULT(ecr);
struct scatterlist dst, src;
struct fscrypt_info *ci = inode->i_crypt_info;
struct crypto_ablkcipher *tfm = ci->ci_ctfm;
int res = 0;
req = ablkcipher_request_alloc(tfm, GFP_NOFS);
if (!req) {
printk_ratelimited(KERN_ERR
"%s: crypto_request_alloc() failed\n",
__func__);
return -ENOMEM;
}
ablkcipher_request_set_callback(
req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
fscrypt_complete, &ecr);
BUILD_BUG_ON(FS_XTS_TWEAK_SIZE < sizeof(index));
memcpy(xts_tweak, &inode->i_ino, sizeof(index));
memset(&xts_tweak[sizeof(index)], 0,
FS_XTS_TWEAK_SIZE - sizeof(index));
sg_init_table(&dst, 1);
sg_set_page(&dst, dest_page, PAGE_CACHE_SIZE, 0);
sg_init_table(&src, 1);
sg_set_page(&src, src_page, PAGE_CACHE_SIZE, 0);
ablkcipher_request_set_crypt(req, &src, &dst, PAGE_CACHE_SIZE,
xts_tweak);
if (rw == FS_DECRYPT)
res = crypto_ablkcipher_decrypt(req);
else
res = crypto_ablkcipher_encrypt(req);
if (res == -EINPROGRESS || res == -EBUSY) {
BUG_ON(req->base.data != &ecr);
wait_for_completion(&ecr.completion);
res = ecr.res;
}
ablkcipher_request_free(req);
if (res) {
printk_ratelimited(KERN_ERR
"%s: crypto_ablkcipher_encrypt() returned %d\n",
__func__, res);
return res;
}
return 0;
}
static struct page *alloc_bounce_page(struct fscrypt_ctx *ctx)
{
ctx->w.bounce_page = mempool_alloc(fscrypt_bounce_page_pool,
GFP_NOWAIT);
if (ctx->w.bounce_page == NULL)
return ERR_PTR(-ENOMEM);
ctx->flags |= FS_WRITE_PATH_FL;
return ctx->w.bounce_page;
}
/**
* fscypt_encrypt_page() - Encrypts a page
* @inode: The inode for which the encryption should take place
* @plaintext_page: The page to encrypt. Must be locked.
*
* Allocates a ciphertext page and encrypts plaintext_page into it using the ctx
* encryption context.
*
* Called on the page write path. The caller must call
* fscrypt_restore_control_page() on the returned ciphertext page to
* release the bounce buffer and the encryption context.
*
* Return: An allocated page with the encrypted content on success. Else, an
* error value or NULL.
*/
struct page *fscrypt_encrypt_page(struct inode *inode,
struct page *plaintext_page)
{
struct fscrypt_ctx *ctx;
struct page *ciphertext_page = NULL;
int err;
BUG_ON(!PageLocked(plaintext_page));
ctx = fscrypt_get_ctx(inode);
if (IS_ERR(ctx))
return (struct page *)ctx;
/* The encryption operation will require a bounce page. */
ciphertext_page = alloc_bounce_page(ctx);
if (IS_ERR(ciphertext_page))
goto errout;
ctx->w.control_page = plaintext_page;
err = do_page_crypto(inode, FS_ENCRYPT, plaintext_page->index,
plaintext_page, ciphertext_page);
if (err) {
ciphertext_page = ERR_PTR(err);
goto errout;
}
SetPagePrivate(ciphertext_page);
set_page_private(ciphertext_page, (unsigned long)ctx);
lock_page(ciphertext_page);
return ciphertext_page;
errout:
fscrypt_release_ctx(ctx);
return ciphertext_page;
}
EXPORT_SYMBOL(fscrypt_encrypt_page);
/**
* f2crypt_decrypt_page() - Decrypts a page in-place
* @page: The page to decrypt. Must be locked.
*
* Decrypts page in-place using the ctx encryption context.
*
* Called from the read completion callback.
*
* Return: Zero on success, non-zero otherwise.
*/
int fscrypt_decrypt_page(struct page *page)
{
BUG_ON(!PageLocked(page));
return do_page_crypto(page->mapping->host,
FS_DECRYPT, page->index, page, page);
}
EXPORT_SYMBOL(fscrypt_decrypt_page);
int fscrypt_zeroout_range(struct inode *inode, pgoff_t lblk,
sector_t pblk, unsigned int len)
{
struct fscrypt_ctx *ctx;
struct page *ciphertext_page = NULL;
struct bio *bio;
int ret, err = 0;
BUG_ON(inode->i_sb->s_blocksize != PAGE_CACHE_SIZE);
ctx = fscrypt_get_ctx(inode);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
ciphertext_page = alloc_bounce_page(ctx);
if (IS_ERR(ciphertext_page)) {
err = PTR_ERR(ciphertext_page);
goto errout;
}
while (len--) {
err = do_page_crypto(inode, FS_ENCRYPT, lblk,
ZERO_PAGE(0), ciphertext_page);
if (err)
goto errout;
bio = bio_alloc(GFP_KERNEL, 1);
if (!bio) {
err = -ENOMEM;
goto errout;
}
bio->bi_bdev = inode->i_sb->s_bdev;
bio->bi_iter.bi_sector =
pblk << (inode->i_sb->s_blocksize_bits - 9);
ret = bio_add_page(bio, ciphertext_page,
inode->i_sb->s_blocksize, 0);
if (ret != inode->i_sb->s_blocksize) {
/* should never happen! */
WARN_ON(1);
bio_put(bio);
err = -EIO;
goto errout;
}
err = submit_bio_wait(WRITE, bio);
if ((err == 0) && bio->bi_error)
err = -EIO;
bio_put(bio);
if (err)
goto errout;
lblk++;
pblk++;
}
err = 0;
errout:
fscrypt_release_ctx(ctx);
return err;
}
EXPORT_SYMBOL(fscrypt_zeroout_range);
/*
* Validate dentries for encrypted directories to make sure we aren't
* potentially caching stale data after a key has been added or
* removed.
*/
static int fscrypt_d_revalidate(struct dentry *dentry, unsigned int flags)
{
struct inode *dir = d_inode(dentry->d_parent);
struct fscrypt_info *ci = dir->i_crypt_info;
int dir_has_key, cached_with_key;
if (!dir->i_sb->s_cop->is_encrypted(dir))
return 0;
if (ci && ci->ci_keyring_key &&
(ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
(1 << KEY_FLAG_REVOKED) |
(1 << KEY_FLAG_DEAD))))
ci = NULL;
/* this should eventually be an flag in d_flags */
spin_lock(&dentry->d_lock);
cached_with_key = dentry->d_flags & DCACHE_ENCRYPTED_WITH_KEY;
spin_unlock(&dentry->d_lock);
dir_has_key = (ci != NULL);
/*
* If the dentry was cached without the key, and it is a
* negative dentry, it might be a valid name. We can't check
* if the key has since been made available due to locking
* reasons, so we fail the validation so ext4_lookup() can do
* this check.
*
* We also fail the validation if the dentry was created with
* the key present, but we no longer have the key, or vice versa.
*/
if ((!cached_with_key && d_is_negative(dentry)) ||
(!cached_with_key && dir_has_key) ||
(cached_with_key && !dir_has_key))
return 0;
return 1;
}
const struct dentry_operations fscrypt_d_ops = {
.d_revalidate = fscrypt_d_revalidate,
};
EXPORT_SYMBOL(fscrypt_d_ops);
/*
* Call fscrypt_decrypt_page on every single page, reusing the encryption
* context.
*/
static void completion_pages(struct work_struct *work)
{
struct fscrypt_ctx *ctx =
container_of(work, struct fscrypt_ctx, r.work);
struct bio *bio = ctx->r.bio;
struct bio_vec *bv;
int i;
bio_for_each_segment_all(bv, bio, i) {
struct page *page = bv->bv_page;
int ret = fscrypt_decrypt_page(page);
if (ret) {
WARN_ON_ONCE(1);
SetPageError(page);
} else {
SetPageUptodate(page);
}
unlock_page(page);
}
fscrypt_release_ctx(ctx);
bio_put(bio);
}
void fscrypt_decrypt_bio_pages(struct fscrypt_ctx *ctx, struct bio *bio)
{
INIT_WORK(&ctx->r.work, completion_pages);
ctx->r.bio = bio;
queue_work(fscrypt_read_workqueue, &ctx->r.work);
}
EXPORT_SYMBOL(fscrypt_decrypt_bio_pages);
void fscrypt_pullback_bio_page(struct page **page, bool restore)
{
struct fscrypt_ctx *ctx;
struct page *bounce_page;
/* The bounce data pages are unmapped. */
if ((*page)->mapping)
return;
/* The bounce data page is unmapped. */
bounce_page = *page;
ctx = (struct fscrypt_ctx *)page_private(bounce_page);
/* restore control page */
*page = ctx->w.control_page;
if (restore)
fscrypt_restore_control_page(bounce_page);
}
EXPORT_SYMBOL(fscrypt_pullback_bio_page);
void fscrypt_restore_control_page(struct page *page)
{
struct fscrypt_ctx *ctx;
ctx = (struct fscrypt_ctx *)page_private(page);
set_page_private(page, (unsigned long)NULL);
ClearPagePrivate(page);
unlock_page(page);
fscrypt_release_ctx(ctx);
}
EXPORT_SYMBOL(fscrypt_restore_control_page);
static void fscrypt_destroy(void)
{
struct fscrypt_ctx *pos, *n;
list_for_each_entry_safe(pos, n, &fscrypt_free_ctxs, free_list)
kmem_cache_free(fscrypt_ctx_cachep, pos);
INIT_LIST_HEAD(&fscrypt_free_ctxs);
mempool_destroy(fscrypt_bounce_page_pool);
fscrypt_bounce_page_pool = NULL;
}
/**
* fscrypt_initialize() - allocate major buffers for fs encryption.
*
* We only call this when we start accessing encrypted files, since it
* results in memory getting allocated that wouldn't otherwise be used.
*
* Return: Zero on success, non-zero otherwise.
*/
int fscrypt_initialize(void)
{
int i, res = -ENOMEM;
if (fscrypt_bounce_page_pool)
return 0;
mutex_lock(&fscrypt_init_mutex);
if (fscrypt_bounce_page_pool)
goto already_initialized;
for (i = 0; i < num_prealloc_crypto_ctxs; i++) {
struct fscrypt_ctx *ctx;
ctx = kmem_cache_zalloc(fscrypt_ctx_cachep, GFP_NOFS);
if (!ctx)
goto fail;
list_add(&ctx->free_list, &fscrypt_free_ctxs);
}
fscrypt_bounce_page_pool =
mempool_create_page_pool(num_prealloc_crypto_pages, 0);
if (!fscrypt_bounce_page_pool)
goto fail;
already_initialized:
mutex_unlock(&fscrypt_init_mutex);
return 0;
fail:
fscrypt_destroy();
mutex_unlock(&fscrypt_init_mutex);
return res;
}
EXPORT_SYMBOL(fscrypt_initialize);
/**
* fscrypt_init() - Set up for fs encryption.
*/
static int __init fscrypt_init(void)
{
fscrypt_read_workqueue = alloc_workqueue("fscrypt_read_queue",
WQ_HIGHPRI, 0);
if (!fscrypt_read_workqueue)
goto fail;
fscrypt_ctx_cachep = KMEM_CACHE(fscrypt_ctx, SLAB_RECLAIM_ACCOUNT);
if (!fscrypt_ctx_cachep)
goto fail_free_queue;
fscrypt_info_cachep = KMEM_CACHE(fscrypt_info, SLAB_RECLAIM_ACCOUNT);
if (!fscrypt_info_cachep)
goto fail_free_ctx;
return 0;
fail_free_ctx:
kmem_cache_destroy(fscrypt_ctx_cachep);
fail_free_queue:
destroy_workqueue(fscrypt_read_workqueue);
fail:
return -ENOMEM;
}
module_init(fscrypt_init)
/**
* fscrypt_exit() - Shutdown the fs encryption system
*/
static void __exit fscrypt_exit(void)
{
fscrypt_destroy();
if (fscrypt_read_workqueue)
destroy_workqueue(fscrypt_read_workqueue);
kmem_cache_destroy(fscrypt_ctx_cachep);
kmem_cache_destroy(fscrypt_info_cachep);
}
module_exit(fscrypt_exit);
MODULE_LICENSE("GPL");

247
fs/f2fs/crypto_fname.c → fs/crypto/fname.c
View File

@ -1,46 +1,35 @@
/*
* linux/fs/f2fs/crypto_fname.c
*
* Copied from linux/fs/ext4/crypto.c
* This contains functions for filename crypto management
*
* Copyright (C) 2015, Google, Inc.
* Copyright (C) 2015, Motorola Mobility
*
* This contains functions for filename crypto management in f2fs
*
* Written by Uday Savagaonkar, 2014.
*
* Adjust f2fs dentry structure
* Jaegeuk Kim, 2015.
* Modified by Jaegeuk Kim, 2015.
*
* This has not yet undergone a rigorous security audit.
*/
#include <crypto/hash.h>
#include <crypto/sha.h>
#include <keys/encrypted-type.h>
#include <keys/user-type.h>
#include <linux/crypto.h>
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/key.h>
#include <linux/list.h>
#include <linux/mempool.h>
#include <linux/random.h>
#include <linux/scatterlist.h>
#include <linux/spinlock_types.h>
#include <linux/f2fs_fs.h>
#include <linux/ratelimit.h>
#include <linux/fscrypto.h>
#include "f2fs.h"
#include "f2fs_crypto.h"
#include "xattr.h"
static u32 size_round_up(size_t size, size_t blksize)
{
return ((size + blksize - 1) / blksize) * blksize;
}
/**
* f2fs_dir_crypt_complete() -
* dir_crypt_complete() -
*/
static void f2fs_dir_crypt_complete(struct crypto_async_request *req, int res)
static void dir_crypt_complete(struct crypto_async_request *req, int res)
{
struct f2fs_completion_result *ecr = req->data;
struct fscrypt_completion_result *ecr = req->data;
if (res == -EINPROGRESS)
return;
@ -48,45 +37,35 @@ static void f2fs_dir_crypt_complete(struct crypto_async_request *req, int res)
complete(&ecr->completion);
}
bool f2fs_valid_filenames_enc_mode(uint32_t mode)
{
return (mode == F2FS_ENCRYPTION_MODE_AES_256_CTS);
}
static unsigned max_name_len(struct inode *inode)
{
return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
F2FS_NAME_LEN;
}
/**
* f2fs_fname_encrypt() -
* fname_encrypt() -
*
* This function encrypts the input filename, and returns the length of the
* ciphertext. Errors are returned as negative numbers. We trust the caller to
* allocate sufficient memory to oname string.
*/
static int f2fs_fname_encrypt(struct inode *inode,
const struct qstr *iname, struct f2fs_str *oname)
static int fname_encrypt(struct inode *inode,
const struct qstr *iname, struct fscrypt_str *oname)
{
u32 ciphertext_len;
struct ablkcipher_request *req = NULL;
DECLARE_F2FS_COMPLETION_RESULT(ecr);
struct f2fs_crypt_info *ci = F2FS_I(inode)->i_crypt_info;
DECLARE_FS_COMPLETION_RESULT(ecr);
struct fscrypt_info *ci = inode->i_crypt_info;
struct crypto_ablkcipher *tfm = ci->ci_ctfm;
int res = 0;
char iv[F2FS_CRYPTO_BLOCK_SIZE];
char iv[FS_CRYPTO_BLOCK_SIZE];
struct scatterlist src_sg, dst_sg;
int padding = 4 << (ci->ci_flags & F2FS_POLICY_FLAGS_PAD_MASK);
int padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK);
char *workbuf, buf[32], *alloc_buf = NULL;
unsigned lim = max_name_len(inode);
unsigned lim;
lim = inode->i_sb->s_cop->max_namelen(inode);
if (iname->len <= 0 || iname->len > lim)
return -EIO;
ciphertext_len = (iname->len < F2FS_CRYPTO_BLOCK_SIZE) ?
F2FS_CRYPTO_BLOCK_SIZE : iname->len;
ciphertext_len = f2fs_fname_crypto_round_up(ciphertext_len, padding);
ciphertext_len = (iname->len < FS_CRYPTO_BLOCK_SIZE) ?
FS_CRYPTO_BLOCK_SIZE : iname->len;
ciphertext_len = size_round_up(ciphertext_len, padding);
ciphertext_len = (ciphertext_len > lim) ? lim : ciphertext_len;
if (ciphertext_len <= sizeof(buf)) {
@ -108,7 +87,7 @@ static int f2fs_fname_encrypt(struct inode *inode,
}
ablkcipher_request_set_callback(req,
CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
f2fs_dir_crypt_complete, &ecr);
dir_crypt_complete, &ecr);
/* Copy the input */
memcpy(workbuf, iname->name, iname->len);
@ -116,7 +95,7 @@ static int f2fs_fname_encrypt(struct inode *inode,
memset(workbuf + iname->len, 0, ciphertext_len - iname->len);
/* Initialize IV */
memset(iv, 0, F2FS_CRYPTO_BLOCK_SIZE);
memset(iv, 0, FS_CRYPTO_BLOCK_SIZE);
/* Create encryption request */
sg_init_one(&src_sg, workbuf, ciphertext_len);
@ -129,33 +108,35 @@ static int f2fs_fname_encrypt(struct inode *inode,
}
kfree(alloc_buf);
ablkcipher_request_free(req);
if (res < 0) {
if (res < 0)
printk_ratelimited(KERN_ERR
"%s: Error (error code %d)\n", __func__, res);
}
oname->len = ciphertext_len;
return res;
}
/*
* f2fs_fname_decrypt()
* fname_decrypt()
* This function decrypts the input filename, and returns
* the length of the plaintext.
* Errors are returned as negative numbers.
* We trust the caller to allocate sufficient memory to oname string.
*/
static int f2fs_fname_decrypt(struct inode *inode,
const struct f2fs_str *iname, struct f2fs_str *oname)
static int fname_decrypt(struct inode *inode,
const struct fscrypt_str *iname,
struct fscrypt_str *oname)
{
struct ablkcipher_request *req = NULL;
DECLARE_F2FS_COMPLETION_RESULT(ecr);
DECLARE_FS_COMPLETION_RESULT(ecr);
struct scatterlist src_sg, dst_sg;
struct f2fs_crypt_info *ci = F2FS_I(inode)->i_crypt_info;
struct fscrypt_info *ci = inode->i_crypt_info;
struct crypto_ablkcipher *tfm = ci->ci_ctfm;
int res = 0;
char iv[F2FS_CRYPTO_BLOCK_SIZE];
unsigned lim = max_name_len(inode);
char iv[FS_CRYPTO_BLOCK_SIZE];
unsigned lim;
lim = inode->i_sb->s_cop->max_namelen(inode);
if (iname->len <= 0 || iname->len > lim)
return -EIO;
@ -168,10 +149,10 @@ static int f2fs_fname_decrypt(struct inode *inode,
}
ablkcipher_request_set_callback(req,
CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
f2fs_dir_crypt_complete, &ecr);
dir_crypt_complete, &ecr);
/* Initialize IV */
memset(iv, 0, F2FS_CRYPTO_BLOCK_SIZE);
memset(iv, 0, FS_CRYPTO_BLOCK_SIZE);
/* Create decryption request */
sg_init_one(&src_sg, iname->name, iname->len);
@ -185,8 +166,7 @@ static int f2fs_fname_decrypt(struct inode *inode,
ablkcipher_request_free(req);
if (res < 0) {
printk_ratelimited(KERN_ERR
"%s: Error in f2fs_fname_decrypt (error code %d)\n",
__func__, res);
"%s: Error (error code %d)\n", __func__, res);
return res;
}
@ -198,7 +178,7 @@ static const char *lookup_table =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,";
/**
* f2fs_fname_encode_digest() -
* digest_encode() -
*
* Encodes the input digest using characters from the set [a-zA-Z0-9_+].
* The encoded string is roughly 4/3 times the size of the input string.
@ -247,156 +227,152 @@ static int digest_decode(const char *src, int len, char *dst)
return cp - dst;
}
/**
* f2fs_fname_crypto_round_up() -
*
* Return: The next multiple of block size
*/
u32 f2fs_fname_crypto_round_up(u32 size, u32 blksize)
u32 fscrypt_fname_encrypted_size(struct inode *inode, u32 ilen)
{
return ((size + blksize - 1) / blksize) * blksize;
}
unsigned f2fs_fname_encrypted_size(struct inode *inode, u32 ilen)
{
struct f2fs_crypt_info *ci = F2FS_I(inode)->i_crypt_info;
int padding = 32;
struct fscrypt_info *ci = inode->i_crypt_info;
if (ci)
padding = 4 << (ci->ci_flags & F2FS_POLICY_FLAGS_PAD_MASK);
if (ilen < F2FS_CRYPTO_BLOCK_SIZE)
ilen = F2FS_CRYPTO_BLOCK_SIZE;
return f2fs_fname_crypto_round_up(ilen, padding);
padding = 4 << (ci->ci_flags & FS_POLICY_FLAGS_PAD_MASK);
if (ilen < FS_CRYPTO_BLOCK_SIZE)
ilen = FS_CRYPTO_BLOCK_SIZE;
return size_round_up(ilen, padding);
}
EXPORT_SYMBOL(fscrypt_fname_encrypted_size);
/**
* f2fs_fname_crypto_alloc_obuff() -
* fscrypt_fname_crypto_alloc_obuff() -
*
* Allocates an output buffer that is sufficient for the crypto operation
* specified by the context and the direction.
*/
int f2fs_fname_crypto_alloc_buffer(struct inode *inode,
u32 ilen, struct f2fs_str *crypto_str)
int fscrypt_fname_alloc_buffer(struct inode *inode,
u32 ilen, struct fscrypt_str *crypto_str)
{
unsigned int olen = f2fs_fname_encrypted_size(inode, ilen);
unsigned int olen = fscrypt_fname_encrypted_size(inode, ilen);
crypto_str->len = olen;
if (olen < F2FS_FNAME_CRYPTO_DIGEST_SIZE * 2)
olen = F2FS_FNAME_CRYPTO_DIGEST_SIZE * 2;
/* Allocated buffer can hold one more character to null-terminate the
* string */
if (olen < FS_FNAME_CRYPTO_DIGEST_SIZE * 2)
olen = FS_FNAME_CRYPTO_DIGEST_SIZE * 2;
/*
* Allocated buffer can hold one more character to null-terminate the
* string
*/
crypto_str->name = kmalloc(olen + 1, GFP_NOFS);
if (!(crypto_str->name))
return -ENOMEM;
return 0;
}
EXPORT_SYMBOL(fscrypt_fname_alloc_buffer);
/**
* f2fs_fname_crypto_free_buffer() -
* fscrypt_fname_crypto_free_buffer() -
*
* Frees the buffer allocated for crypto operation.
*/
void f2fs_fname_crypto_free_buffer(struct f2fs_str *crypto_str)
void fscrypt_fname_free_buffer(struct fscrypt_str *crypto_str)
{
if (!crypto_str)
return;
kfree(crypto_str->name);
crypto_str->name = NULL;
}
EXPORT_SYMBOL(fscrypt_fname_free_buffer);
/**
* f2fs_fname_disk_to_usr() - converts a filename from disk space to user space
* fscrypt_fname_disk_to_usr() - converts a filename from disk space to user
* space
*/
int f2fs_fname_disk_to_usr(struct inode *inode,
f2fs_hash_t *hash,
const struct f2fs_str *iname,
struct f2fs_str *oname)
int fscrypt_fname_disk_to_usr(struct inode *inode,
u32 hash, u32 minor_hash,
const struct fscrypt_str *iname,
struct fscrypt_str *oname)
{
const struct qstr qname = FSTR_TO_QSTR(iname);
char buf[24];
int ret;
if (is_dot_dotdot(&qname)) {
if (fscrypt_is_dot_dotdot(&qname)) {
oname->name[0] = '.';
oname->name[iname->len - 1] = '.';
oname->len = iname->len;
return oname->len;
}
if (iname->len < F2FS_CRYPTO_BLOCK_SIZE) {
printk("encrypted inode too small");
return -EUCLEAN;
}
if (F2FS_I(inode)->i_crypt_info)
return f2fs_fname_decrypt(inode, iname, oname);
if (iname->len <= F2FS_FNAME_CRYPTO_DIGEST_SIZE) {
if (iname->len < FS_CRYPTO_BLOCK_SIZE)
return -EUCLEAN;
if (inode->i_crypt_info)
return fname_decrypt(inode, iname, oname);
if (iname->len <= FS_FNAME_CRYPTO_DIGEST_SIZE) {
ret = digest_encode(iname->name, iname->len, oname->name);
oname->len = ret;
return ret;
}
if (hash) {
memcpy(buf, hash, 4);
memset(buf + 4, 0, 4);
} else
memcpy(buf, &hash, 4);
memcpy(buf + 4, &minor_hash, 4);
} else {
memset(buf, 0, 8);
}
memcpy(buf + 8, iname->name + iname->len - 16, 16);
oname->name[0] = '_';
ret = digest_encode(buf, 24, oname->name + 1);
oname->len = ret + 1;
return ret + 1;
}
EXPORT_SYMBOL(fscrypt_fname_disk_to_usr);
/**
* f2fs_fname_usr_to_disk() - converts a filename from user space to disk space
* fscrypt_fname_usr_to_disk() - converts a filename from user space to disk
* space
*/
int f2fs_fname_usr_to_disk(struct inode *inode,
int fscrypt_fname_usr_to_disk(struct inode *inode,
const struct qstr *iname,
struct f2fs_str *oname)
struct fscrypt_str *oname)
{
int res;
struct f2fs_crypt_info *ci = F2FS_I(inode)->i_crypt_info;
if (is_dot_dotdot(iname)) {
if (fscrypt_is_dot_dotdot(iname)) {
oname->name[0] = '.';
oname->name[iname->len - 1] = '.';
oname->len = iname->len;
return oname->len;
}
if (ci) {
res = f2fs_fname_encrypt(inode, iname, oname);
return res;
}
/* Without a proper key, a user is not allowed to modify the filenames
if (inode->i_crypt_info)
return fname_encrypt(inode, iname, oname);
/*
* Without a proper key, a user is not allowed to modify the filenames
* in a directory. Consequently, a user space name cannot be mapped to
* a disk-space name */
* a disk-space name
*/
return -EACCES;
}
EXPORT_SYMBOL(fscrypt_fname_usr_to_disk);
int f2fs_fname_setup_filename(struct inode *dir, const struct qstr *iname,
int lookup, struct f2fs_filename *fname)
int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
int lookup, struct fscrypt_name *fname)
{
struct f2fs_crypt_info *ci;
int ret = 0, bigname = 0;
memset(fname, 0, sizeof(struct f2fs_filename));
memset(fname, 0, sizeof(struct fscrypt_name));
fname->usr_fname = iname;
if (!f2fs_encrypted_inode(dir) || is_dot_dotdot(iname)) {
if (!dir->i_sb->s_cop->is_encrypted(dir) ||
fscrypt_is_dot_dotdot(iname)) {
fname->disk_name.name = (unsigned char *)iname->name;
fname->disk_name.len = iname->len;
return 0;
}
ret = f2fs_get_encryption_info(dir);
if (ret)
ret = get_crypt_info(dir);
if (ret && ret != -EOPNOTSUPP)
return ret;
ci = F2FS_I(dir)->i_crypt_info;
if (ci) {
ret = f2fs_fname_crypto_alloc_buffer(dir, iname->len,
&fname->crypto_buf);
if (dir->i_crypt_info) {
ret = fscrypt_fname_alloc_buffer(dir, iname->len,
&fname->crypto_buf);
if (ret < 0)
return ret;
ret = f2fs_fname_encrypt(dir, iname, &fname->crypto_buf);
ret = fname_encrypt(dir, iname, &fname->crypto_buf);
if (ret < 0)
goto errout;
fname->disk_name.name = fname->crypto_buf.name;
@ -406,18 +382,19 @@ int f2fs_fname_setup_filename(struct inode *dir, const struct qstr *iname,
if (!lookup)
return -EACCES;
/* We don't have the key and we are doing a lookup; decode the
/*
* We don't have the key and we are doing a lookup; decode the
* user-supplied name
*/
if (iname->name[0] == '_')
bigname = 1;
if ((bigname && (iname->len != 33)) ||
(!bigname && (iname->len > 43)))
if ((bigname && (iname->len != 33)) || (!bigname && (iname->len > 43)))
return -ENOENT;
fname->crypto_buf.name = kmalloc(32, GFP_KERNEL);
if (fname->crypto_buf.name == NULL)
return -ENOMEM;
ret = digest_decode(iname->name + bigname, iname->len - bigname,
fname->crypto_buf.name);
if (ret < 0) {
@ -427,20 +404,24 @@ int f2fs_fname_setup_filename(struct inode *dir, const struct qstr *iname,
fname->crypto_buf.len = ret;
if (bigname) {
memcpy(&fname->hash, fname->crypto_buf.name, 4);
memcpy(&fname->minor_hash, fname->crypto_buf.name + 4, 4);
} else {
fname->disk_name.name = fname->crypto_buf.name;
fname->disk_name.len = fname->crypto_buf.len;
}
return 0;
errout:
f2fs_fname_crypto_free_buffer(&fname->crypto_buf);
fscrypt_fname_free_buffer(&fname->crypto_buf);
return ret;
}
EXPORT_SYMBOL(fscrypt_setup_filename);
void f2fs_fname_free_filename(struct f2fs_filename *fname)
void fscrypt_free_filename(struct fscrypt_name *fname)
{
kfree(fname->crypto_buf.name);
fname->crypto_buf.name = NULL;
fname->usr_fname = NULL;
fname->disk_name.name = NULL;
}
EXPORT_SYMBOL(fscrypt_free_filename);

189
fs/f2fs/crypto_key.c → fs/crypto/keyinfo.c
View File

@ -1,28 +1,24 @@
/*
* linux/fs/f2fs/crypto_key.c
*
* Copied from linux/fs/f2fs/crypto_key.c
* key management facility for FS encryption support.
*
* Copyright (C) 2015, Google, Inc.
*
* This contains encryption key functions for f2fs
* 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 <crypto/hash.h>
#include <linux/f2fs_fs.h>
#include "f2fs.h"
#include "xattr.h"
#include <linux/fscrypto.h>
static void derive_crypt_complete(struct crypto_async_request *req, int rc)
{
struct f2fs_completion_result *ecr = req->data;
struct fscrypt_completion_result *ecr = req->data;
if (rc == -EINPROGRESS)
return;
@ -32,20 +28,20 @@ static void derive_crypt_complete(struct crypto_async_request *req, int rc)
}
/**
* f2fs_derive_key_aes() - Derive a key using AES-128-ECB
* 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 f2fs_derive_key_aes(char deriving_key[F2FS_AES_128_ECB_KEY_SIZE],
char source_key[F2FS_AES_256_XTS_KEY_SIZE],
char derived_key[F2FS_AES_256_XTS_KEY_SIZE])
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 ablkcipher_request *req = NULL;
DECLARE_F2FS_COMPLETION_RESULT(ecr);
DECLARE_FS_COMPLETION_RESULT(ecr);
struct scatterlist src_sg, dst_sg;
struct crypto_ablkcipher *tfm = crypto_alloc_ablkcipher("ecb(aes)", 0,
0);
@ -65,14 +61,14 @@ static int f2fs_derive_key_aes(char deriving_key[F2FS_AES_128_ECB_KEY_SIZE],
CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
derive_crypt_complete, &ecr);
res = crypto_ablkcipher_setkey(tfm, deriving_key,
F2FS_AES_128_ECB_KEY_SIZE);
FS_AES_128_ECB_KEY_SIZE);
if (res < 0)
goto out;
sg_init_one(&src_sg, source_key, F2FS_AES_256_XTS_KEY_SIZE);
sg_init_one(&dst_sg, derived_key, F2FS_AES_256_XTS_KEY_SIZE);
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);
ablkcipher_request_set_crypt(req, &src_sg, &dst_sg,
F2FS_AES_256_XTS_KEY_SIZE, NULL);
FS_AES_256_XTS_KEY_SIZE, NULL);
res = crypto_ablkcipher_encrypt(req);
if (res == -EINPROGRESS || res == -EBUSY) {
wait_for_completion(&ecr.completion);
@ -86,71 +82,61 @@ out:
return res;
}
static void f2fs_free_crypt_info(struct f2fs_crypt_info *ci)
static void put_crypt_info(struct fscrypt_info *ci)
{
if (!ci)
return;
key_put(ci->ci_keyring_key);
if (ci->ci_keyring_key)
key_put(ci->ci_keyring_key);
crypto_free_ablkcipher(ci->ci_ctfm);
kmem_cache_free(f2fs_crypt_info_cachep, ci);
kmem_cache_free(fscrypt_info_cachep, ci);
}
void f2fs_free_encryption_info(struct inode *inode, struct f2fs_crypt_info *ci)
int get_crypt_info(struct inode *inode)
{
struct f2fs_inode_info *fi = F2FS_I(inode);
struct f2fs_crypt_info *prev;
if (ci == NULL)
ci = ACCESS_ONCE(fi->i_crypt_info);
if (ci == NULL)
return;
prev = cmpxchg(&fi->i_crypt_info, ci, NULL);
if (prev != ci)
return;
f2fs_free_crypt_info(ci);
}
int _f2fs_get_encryption_info(struct inode *inode)
{
struct f2fs_inode_info *fi = F2FS_I(inode);
struct f2fs_crypt_info *crypt_info;
char full_key_descriptor[F2FS_KEY_DESC_PREFIX_SIZE +
(F2FS_KEY_DESCRIPTOR_SIZE * 2) + 1];
struct fscrypt_info *crypt_info;
u8 full_key_descriptor[FS_KEY_DESC_PREFIX_SIZE +
(FS_KEY_DESCRIPTOR_SIZE * 2) + 1];
struct key *keyring_key = NULL;
struct f2fs_encryption_key *master_key;
struct f2fs_encryption_context ctx;
struct fscrypt_key *master_key;
struct fscrypt_context ctx;
const struct user_key_payload *ukp;
struct crypto_ablkcipher *ctfm;
const char *cipher_str;
char raw_key[F2FS_MAX_KEY_SIZE];
char mode;
u8 raw_key[FS_MAX_KEY_SIZE];
u8 mode;
int res;
res = f2fs_crypto_initialize();
res = fscrypt_initialize();
if (res)
return res;
if (!inode->i_sb->s_cop->get_context)
return -EOPNOTSUPP;
retry:
crypt_info = ACCESS_ONCE(fi->i_crypt_info);
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;
f2fs_free_encryption_info(inode, crypt_info);
fscrypt_put_encryption_info(inode, crypt_info);
goto retry;
}
res = f2fs_getxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
F2FS_XATTR_NAME_ENCRYPTION_CONTEXT,
&ctx, sizeof(ctx), NULL);
if (res < 0)
return res;
else if (res != sizeof(ctx))
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(f2fs_crypt_info_cachep, GFP_NOFS);
crypt_info = kmem_cache_alloc(fscrypt_info_cachep, GFP_NOFS);
if (!crypt_info)
return -ENOMEM;
@ -169,27 +155,30 @@ retry:
BUG();
switch (mode) {
case F2FS_ENCRYPTION_MODE_AES_256_XTS:
case FS_ENCRYPTION_MODE_AES_256_XTS:
cipher_str = "xts(aes)";
break;
case F2FS_ENCRYPTION_MODE_AES_256_CTS:
case FS_ENCRYPTION_MODE_AES_256_CTS:
cipher_str = "cts(cbc(aes))";
break;
default:
printk_once(KERN_WARNING
"f2fs: unsupported key mode %d (ino %u)\n",
mode, (unsigned) inode->i_ino);
"%s: unsupported key mode %d (ino %u)\n",
__func__, mode, (unsigned) inode->i_ino);
res = -ENOKEY;
goto out;
}
memcpy(full_key_descriptor, F2FS_KEY_DESC_PREFIX,
F2FS_KEY_DESC_PREFIX_SIZE);
sprintf(full_key_descriptor + F2FS_KEY_DESC_PREFIX_SIZE,
"%*phN", F2FS_KEY_DESCRIPTOR_SIZE,
if (fscrypt_dummy_context_enabled(inode)) {
memset(raw_key, 0x42, FS_AES_256_XTS_KEY_SIZE);
goto got_key;
}
memcpy(full_key_descriptor, FS_KEY_DESC_PREFIX,
FS_KEY_DESC_PREFIX_SIZE);
sprintf(full_key_descriptor + FS_KEY_DESC_PREFIX_SIZE,
"%*phN", FS_KEY_DESCRIPTOR_SIZE,
ctx.master_key_descriptor);
full_key_descriptor[F2FS_KEY_DESC_PREFIX_SIZE +
(2 * F2FS_KEY_DESCRIPTOR_SIZE)] = '\0';
full_key_descriptor[FS_KEY_DESC_PREFIX_SIZE +
(2 * FS_KEY_DESCRIPTOR_SIZE)] = '\0';
keyring_key = request_key(&key_type_logon, full_key_descriptor, NULL);
if (IS_ERR(keyring_key)) {
res = PTR_ERR(keyring_key);
@ -198,34 +187,34 @@ retry:
}
crypt_info->ci_keyring_key = keyring_key;
if (keyring_key->type != &key_type_logon) {
printk_once(KERN_WARNING "f2fs: key type must be logon\n");
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 f2fs_encryption_key)) {
if (ukp->datalen != sizeof(struct fscrypt_key)) {
res = -EINVAL;
up_read(&keyring_key->sem);
goto out;
}
master_key = (struct f2fs_encryption_key *)ukp->data;
BUILD_BUG_ON(F2FS_AES_128_ECB_KEY_SIZE !=
F2FS_KEY_DERIVATION_NONCE_SIZE);
if (master_key->size != F2FS_AES_256_XTS_KEY_SIZE) {
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
"f2fs: key size incorrect: %d\n",
master_key->size);
"%s: key size incorrect: %d\n",
__func__, master_key->size);
res = -ENOKEY;
up_read(&keyring_key->sem);
goto out;
}
res = f2fs_derive_key_aes(ctx.nonce, master_key->raw,
raw_key);
res = derive_key_aes(ctx.nonce, master_key->raw, raw_key);
up_read(&keyring_key->sem);
if (res)
goto out;
got_key:
ctfm = crypto_alloc_ablkcipher(cipher_str, 0, 0);
if (!ctfm || IS_ERR(ctfm)) {
res = ctfm ? PTR_ERR(ctfm) : -ENOMEM;
@ -237,31 +226,53 @@ retry:
crypt_info->ci_ctfm = ctfm;
crypto_ablkcipher_clear_flags(ctfm, ~0);
crypto_tfm_set_flags(crypto_ablkcipher_tfm(ctfm),
CRYPTO_TFM_REQ_WEAK_KEY);
res = crypto_ablkcipher_setkey(ctfm, raw_key,
f2fs_encryption_key_size(mode));
CRYPTO_TFM_REQ_WEAK_KEY);
res = crypto_ablkcipher_setkey(ctfm, raw_key, fscrypt_key_size(mode));
if (res)
goto out;
memzero_explicit(raw_key, sizeof(raw_key));
if (cmpxchg(&fi->i_crypt_info, NULL, crypt_info) != NULL) {
f2fs_free_crypt_info(crypt_info);
if (cmpxchg(&inode->i_crypt_info, NULL, crypt_info) != NULL) {
put_crypt_info(crypt_info);
goto retry;
}
return 0;
out:
if (res == -ENOKEY && !S_ISREG(inode->i_mode))
if (res == -ENOKEY)
res = 0;
f2fs_free_crypt_info(crypt_info);
put_crypt_info(crypt_info);
memzero_explicit(raw_key, sizeof(raw_key));
return res;
}
int f2fs_has_encryption_key(struct inode *inode)
void fscrypt_put_encryption_info(struct inode *inode, struct fscrypt_info *ci)
{
struct f2fs_inode_info *fi = F2FS_I(inode);
struct fscrypt_info *prev;
return (fi->i_crypt_info != NULL);
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);

229
fs/crypto/policy.c Normal file
View File

@ -0,0 +1,229 @@
/*
* Encryption policy functions for per-file encryption support.
*
* Copyright (C) 2015, Google, Inc.
* Copyright (C) 2015, Motorola Mobility.
*
* Written by Michael Halcrow, 2015.
* Modified by Jaegeuk Kim, 2015.
*/
#include <linux/random.h>
#include <linux/string.h>
#include <linux/fscrypto.h>
static int inode_has_encryption_context(struct inode *inode)
{
if (!inode->i_sb->s_cop->get_context)
return 0;
return (inode->i_sb->s_cop->get_context(inode, NULL, 0L) > 0);
}
/*
* check whether the policy is consistent with the encryption context
* for the inode
*/
static int is_encryption_context_consistent_with_policy(struct inode *inode,
const struct fscrypt_policy *policy)
{
struct fscrypt_context ctx;
int res;
if (!inode->i_sb->s_cop->get_context)
return 0;
res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
if (res != sizeof(ctx))
return 0;
return (memcmp(ctx.master_key_descriptor, policy->master_key_descriptor,
FS_KEY_DESCRIPTOR_SIZE) == 0 &&
(ctx.flags == policy->flags) &&
(ctx.contents_encryption_mode ==
policy->contents_encryption_mode) &&
(ctx.filenames_encryption_mode ==
policy->filenames_encryption_mode));
}
static int create_encryption_context_from_policy(struct inode *inode,
const struct fscrypt_policy *policy)
{
struct fscrypt_context ctx;
int res;
if (!inode->i_sb->s_cop->set_context)
return -EOPNOTSUPP;
if (inode->i_sb->s_cop->prepare_context) {
res = inode->i_sb->s_cop->prepare_context(inode);
if (res)
return res;
}
ctx.format = FS_ENCRYPTION_CONTEXT_FORMAT_V1;
memcpy(ctx.master_key_descriptor, policy->master_key_descriptor,
FS_KEY_DESCRIPTOR_SIZE);
if (!fscrypt_valid_contents_enc_mode(
policy->contents_encryption_mode)) {
printk(KERN_WARNING
"%s: Invalid contents encryption mode %d\n", __func__,
policy->contents_encryption_mode);
return -EINVAL;
}
if (!fscrypt_valid_filenames_enc_mode(
policy->filenames_encryption_mode)) {
printk(KERN_WARNING
"%s: Invalid filenames encryption mode %d\n", __func__,
policy->filenames_encryption_mode);
return -EINVAL;
}
if (policy->flags & ~FS_POLICY_FLAGS_VALID)
return -EINVAL;
ctx.contents_encryption_mode = policy->contents_encryption_mode;
ctx.filenames_encryption_mode = policy->filenames_encryption_mode;
ctx.flags = policy->flags;
BUILD_BUG_ON(sizeof(ctx.nonce) != FS_KEY_DERIVATION_NONCE_SIZE);
get_random_bytes(ctx.nonce, FS_KEY_DERIVATION_NONCE_SIZE);
return inode->i_sb->s_cop->set_context(inode, &ctx, sizeof(ctx), NULL);
}
int fscrypt_process_policy(struct inode *inode,
const struct fscrypt_policy *policy)
{
if (policy->version != 0)
return -EINVAL;
if (!inode_has_encryption_context(inode)) {
if (!inode->i_sb->s_cop->empty_dir)
return -EOPNOTSUPP;
if (!inode->i_sb->s_cop->empty_dir(inode))
return -ENOTEMPTY;
return create_encryption_context_from_policy(inode, policy);
}
if (is_encryption_context_consistent_with_policy(inode, policy))
return 0;
printk(KERN_WARNING "%s: Policy inconsistent with encryption context\n",
__func__);
return -EINVAL;
}
EXPORT_SYMBOL(fscrypt_process_policy);
int fscrypt_get_policy(struct inode *inode, struct fscrypt_policy *policy)
{
struct fscrypt_context ctx;
int res;
if (!inode->i_sb->s_cop->get_context ||
!inode->i_sb->s_cop->is_encrypted(inode))
return -ENODATA;
res = inode->i_sb->s_cop->get_context(inode, &ctx, sizeof(ctx));
if (res != sizeof(ctx))
return -ENODATA;
if (ctx.format != FS_ENCRYPTION_CONTEXT_FORMAT_V1)
return -EINVAL;
policy->version = 0;
policy->contents_encryption_mode = ctx.contents_encryption_mode;
policy->filenames_encryption_mode = ctx.filenames_encryption_mode;
policy->flags = ctx.flags;
memcpy(&policy->master_key_descriptor, ctx.master_key_descriptor,
FS_KEY_DESCRIPTOR_SIZE);
return 0;
}
EXPORT_SYMBOL(fscrypt_get_policy);
int fscrypt_has_permitted_context(struct inode *parent, struct inode *child)
{
struct fscrypt_info *parent_ci, *child_ci;
int res;
if ((parent == NULL) || (child == NULL)) {
printk(KERN_ERR "parent %p child %p\n", parent, child);
BUG_ON(1);
}
/* no restrictions if the parent directory is not encrypted */
if (!parent->i_sb->s_cop->is_encrypted(parent))
return 1;
/* if the child directory is not encrypted, this is always a problem */
if (!parent->i_sb->s_cop->is_encrypted(child))
return 0;
res = fscrypt_get_encryption_info(parent);
if (res)
return 0;
res = fscrypt_get_encryption_info(child);
if (res)
return 0;
parent_ci = parent->i_crypt_info;
child_ci = child->i_crypt_info;
if (!parent_ci && !child_ci)
return 1;
if (!parent_ci || !child_ci)
return 0;
return (memcmp(parent_ci->ci_master_key,
child_ci->ci_master_key,
FS_KEY_DESCRIPTOR_SIZE) == 0 &&
(parent_ci->ci_data_mode == child_ci->ci_data_mode) &&
(parent_ci->ci_filename_mode == child_ci->ci_filename_mode) &&
(parent_ci->ci_flags == child_ci->ci_flags));
}
EXPORT_SYMBOL(fscrypt_has_permitted_context);
/**
* fscrypt_inherit_context() - Sets a child context from its parent
* @parent: Parent inode from which the context is inherited.
* @child: Child inode that inherits the context from @parent.
* @fs_data: private data given by FS.
* @preload: preload child i_crypt_info
*
* Return: Zero on success, non-zero otherwise
*/
int fscrypt_inherit_context(struct inode *parent, struct inode *child,
void *fs_data, bool preload)
{
struct fscrypt_context ctx;
struct fscrypt_info *ci;
int res;
if (!parent->i_sb->s_cop->set_context)
return -EOPNOTSUPP;
res = fscrypt_get_encryption_info(parent);
if (res < 0)
return res;
ci = parent->i_crypt_info;
if (ci == NULL)
return -ENOKEY;
ctx.format = FS_ENCRYPTION_CONTEXT_FORMAT_V1;
if (fscrypt_dummy_context_enabled(parent)) {
ctx.contents_encryption_mode = FS_ENCRYPTION_MODE_AES_256_XTS;
ctx.filenames_encryption_mode = FS_ENCRYPTION_MODE_AES_256_CTS;
ctx.flags = 0;
memset(ctx.master_key_descriptor, 0x42, FS_KEY_DESCRIPTOR_SIZE);
res = 0;
} else {
ctx.contents_encryption_mode = ci->ci_data_mode;
ctx.filenames_encryption_mode = ci->ci_filename_mode;
ctx.flags = ci->ci_flags;
memcpy(ctx.master_key_descriptor, ci->ci_master_key,
FS_KEY_DESCRIPTOR_SIZE);
}
get_random_bytes(ctx.nonce, FS_KEY_DERIVATION_NONCE_SIZE);
res = parent->i_sb->s_cop->set_context(child, &ctx,
sizeof(ctx), fs_data);
if (res)
return res;
return preload ? fscrypt_get_encryption_info(child): 0;
}
EXPORT_SYMBOL(fscrypt_inherit_context);

10
fs/f2fs/Kconfig
View File

@ -76,15 +76,7 @@ config F2FS_FS_ENCRYPTION
bool "F2FS Encryption"
depends on F2FS_FS
depends on F2FS_FS_XATTR
select CRYPTO_AES
select CRYPTO_CBC
select CRYPTO_ECB
select CRYPTO_XTS
select CRYPTO_CTS
select CRYPTO_CTR
select CRYPTO_SHA256
select KEYS
select ENCRYPTED_KEYS
select FS_ENCRYPTION
help
Enable encryption of f2fs files and directories. This
feature is similar to ecryptfs, but it is more memory

2
fs/f2fs/Makefile
View File

@ -7,5 +7,3 @@ f2fs-$(CONFIG_F2FS_STAT_FS) += debug.o
f2fs-$(CONFIG_F2FS_FS_XATTR) += xattr.o
f2fs-$(CONFIG_F2FS_FS_POSIX_ACL) += acl.o
f2fs-$(CONFIG_F2FS_IO_TRACE) += trace.o
f2fs-$(CONFIG_F2FS_FS_ENCRYPTION) += crypto_policy.o crypto.o \
crypto_key.o crypto_fname.o

473
fs/f2fs/crypto.c
View File

@ -1,473 +0,0 @@
/*
* linux/fs/f2fs/crypto.c
*
* Copied from linux/fs/ext4/crypto.c
*
* Copyright (C) 2015, Google, Inc.
* Copyright (C) 2015, Motorola Mobility
*
* This contains encryption functions for f2fs
*
* Written by Michael Halcrow, 2014.
*
* Filename encryption additions
* Uday Savagaonkar, 2014
* Encryption policy handling additions
* Ildar Muslukhov, 2014
* Remove ext4_encrypted_zeroout(),
* add f2fs_restore_and_release_control_page()
* Jaegeuk Kim, 2015.
*
* This has not yet undergone a rigorous security audit.
*
* The usage of AES-XTS should conform to recommendations in NIST
* Special Publication 800-38E and IEEE P1619/D16.
*/
#include <crypto/hash.h>
#include <crypto/sha.h>
#include <keys/user-type.h>
#include <keys/encrypted-type.h>
#include <linux/crypto.h>
#include <linux/ecryptfs.h>
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/key.h>
#include <linux/list.h>
#include <linux/mempool.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/random.h>
#include <linux/scatterlist.h>
#include <linux/spinlock_types.h>
#include <linux/f2fs_fs.h>
#include <linux/ratelimit.h>
#include <linux/bio.h>
#include "f2fs.h"
#include "xattr.h"
/* Encryption added and removed here! (L: */
static unsigned int num_prealloc_crypto_pages = 32;
static unsigned int num_prealloc_crypto_ctxs = 128;
module_param(num_prealloc_crypto_pages, uint, 0444);
MODULE_PARM_DESC(num_prealloc_crypto_pages,
"Number of crypto pages to preallocate");
module_param(num_prealloc_crypto_ctxs, uint, 0444);
MODULE_PARM_DESC(num_prealloc_crypto_ctxs,
"Number of crypto contexts to preallocate");
static mempool_t *f2fs_bounce_page_pool;
static LIST_HEAD(f2fs_free_crypto_ctxs);
static DEFINE_SPINLOCK(f2fs_crypto_ctx_lock);
static struct workqueue_struct *f2fs_read_workqueue;
static DEFINE_MUTEX(crypto_init);
static struct kmem_cache *f2fs_crypto_ctx_cachep;
struct kmem_cache *f2fs_crypt_info_cachep;
/**
* f2fs_release_crypto_ctx() - Releases an encryption context
* @ctx: The encryption context to release.
*
* If the encryption context was allocated from the pre-allocated pool, returns
* it to that pool. Else, frees it.
*
* If there's a bounce page in the context, this frees that.
*/
void f2fs_release_crypto_ctx(struct f2fs_crypto_ctx *ctx)
{
unsigned long flags;
if (ctx->flags & F2FS_WRITE_PATH_FL && ctx->w.bounce_page) {
mempool_free(ctx->w.bounce_page, f2fs_bounce_page_pool);
ctx->w.bounce_page = NULL;
}
ctx->w.control_page = NULL;
if (ctx->flags & F2FS_CTX_REQUIRES_FREE_ENCRYPT_FL) {
kmem_cache_free(f2fs_crypto_ctx_cachep, ctx);
} else {
spin_lock_irqsave(&f2fs_crypto_ctx_lock, flags);
list_add(&ctx->free_list, &f2fs_free_crypto_ctxs);
spin_unlock_irqrestore(&f2fs_crypto_ctx_lock, flags);
}
}
/**
* f2fs_get_crypto_ctx() - Gets an encryption context
* @inode: The inode for which we are doing the crypto
*
* Allocates and initializes an encryption context.
*
* Return: An allocated and initialized encryption context on success; error
* value or NULL otherwise.
*/
struct f2fs_crypto_ctx *f2fs_get_crypto_ctx(struct inode *inode)
{
struct f2fs_crypto_ctx *ctx = NULL;
unsigned long flags;
struct f2fs_crypt_info *ci = F2FS_I(inode)->i_crypt_info;
if (ci == NULL)
return ERR_PTR(-ENOKEY);
/*
* We first try getting the ctx from a free list because in
* the common case the ctx will have an allocated and
* initialized crypto tfm, so it's probably a worthwhile
* optimization. For the bounce page, we first try getting it
* from the kernel allocator because that's just about as fast
* as getting it from a list and because a cache of free pages
* should generally be a "last resort" option for a filesystem
* to be able to do its job.
*/
spin_lock_irqsave(&f2fs_crypto_ctx_lock, flags);
ctx = list_first_entry_or_null(&f2fs_free_crypto_ctxs,
struct f2fs_crypto_ctx, free_list);
if (ctx)
list_del(&ctx->free_list);
spin_unlock_irqrestore(&f2fs_crypto_ctx_lock, flags);
if (!ctx) {
ctx = kmem_cache_zalloc(f2fs_crypto_ctx_cachep, GFP_NOFS);
if (!ctx)
return ERR_PTR(-ENOMEM);
ctx->flags |= F2FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
} else {
ctx->flags &= ~F2FS_CTX_REQUIRES_FREE_ENCRYPT_FL;
}
ctx->flags &= ~F2FS_WRITE_PATH_FL;
return ctx;
}
/*
* Call f2fs_decrypt on every single page, reusing the encryption
* context.
*/
static void completion_pages(struct work_struct *work)
{
struct f2fs_crypto_ctx *ctx =
container_of(work, struct f2fs_crypto_ctx, r.work);
struct bio *bio = ctx->r.bio;
struct bio_vec *bv;
int i;
bio_for_each_segment_all(bv, bio, i) {
struct page *page = bv->bv_page;
int ret = f2fs_decrypt(page);
if (ret) {
WARN_ON_ONCE(1);
SetPageError(page);
} else
SetPageUptodate(page);
unlock_page(page);
}
f2fs_release_crypto_ctx(ctx);
bio_put(bio);
}
void f2fs_end_io_crypto_work(struct f2fs_crypto_ctx *ctx, struct bio *bio)
{
INIT_WORK(&ctx->r.work, completion_pages);
ctx->r.bio = bio;
queue_work(f2fs_read_workqueue, &ctx->r.work);
}
static void f2fs_crypto_destroy(void)
{
struct f2fs_crypto_ctx *pos, *n;
list_for_each_entry_safe(pos, n, &f2fs_free_crypto_ctxs, free_list)
kmem_cache_free(f2fs_crypto_ctx_cachep, pos);
INIT_LIST_HEAD(&f2fs_free_crypto_ctxs);
if (f2fs_bounce_page_pool)
mempool_destroy(f2fs_bounce_page_pool);
f2fs_bounce_page_pool = NULL;
}
/**
* f2fs_crypto_initialize() - Set up for f2fs encryption.
*
* We only call this when we start accessing encrypted files, since it
* results in memory getting allocated that wouldn't otherwise be used.
*
* Return: Zero on success, non-zero otherwise.
*/
int f2fs_crypto_initialize(void)
{
int i, res = -ENOMEM;
if (f2fs_bounce_page_pool)
return 0;
mutex_lock(&crypto_init);
if (f2fs_bounce_page_pool)
goto already_initialized;
for (i = 0; i < num_prealloc_crypto_ctxs; i++) {
struct f2fs_crypto_ctx *ctx;
ctx = kmem_cache_zalloc(f2fs_crypto_ctx_cachep, GFP_KERNEL);
if (!ctx)
goto fail;
list_add(&ctx->free_list, &f2fs_free_crypto_ctxs);
}
/* must be allocated at the last step to avoid race condition above */
f2fs_bounce_page_pool =
mempool_create_page_pool(num_prealloc_crypto_pages, 0);
if (!f2fs_bounce_page_pool)
goto fail;
already_initialized:
mutex_unlock(&crypto_init);
return 0;
fail:
f2fs_crypto_destroy();
mutex_unlock(&crypto_init);
return res;
}
/**
* f2fs_exit_crypto() - Shutdown the f2fs encryption system
*/
void f2fs_exit_crypto(void)
{
f2fs_crypto_destroy();
if (f2fs_read_workqueue)
destroy_workqueue(f2fs_read_workqueue);
if (f2fs_crypto_ctx_cachep)
kmem_cache_destroy(f2fs_crypto_ctx_cachep);
if (f2fs_crypt_info_cachep)
kmem_cache_destroy(f2fs_crypt_info_cachep);
}
int __init f2fs_init_crypto(void)
{
int res = -ENOMEM;
f2fs_read_workqueue = alloc_workqueue("f2fs_crypto", WQ_HIGHPRI, 0);
if (!f2fs_read_workqueue)
goto fail;
f2fs_crypto_ctx_cachep = KMEM_CACHE(f2fs_crypto_ctx,
SLAB_RECLAIM_ACCOUNT);
if (!f2fs_crypto_ctx_cachep)
goto fail;
f2fs_crypt_info_cachep = KMEM_CACHE(f2fs_crypt_info,
SLAB_RECLAIM_ACCOUNT);
if (!f2fs_crypt_info_cachep)
goto fail;
return 0;
fail:
f2fs_exit_crypto();
return res;
}
void f2fs_restore_and_release_control_page(struct page **page)
{
struct f2fs_crypto_ctx *ctx;
struct page *bounce_page;
/* The bounce data pages are unmapped. */
if ((*page)->mapping)
return;
/* The bounce data page is unmapped. */
bounce_page = *page;
ctx = (struct f2fs_crypto_ctx *)page_private(bounce_page);
/* restore control page */
*page = ctx->w.control_page;
f2fs_restore_control_page(bounce_page);
}
void f2fs_restore_control_page(struct page *data_page)
{
struct f2fs_crypto_ctx *ctx =
(struct f2fs_crypto_ctx *)page_private(data_page);
set_page_private(data_page, (unsigned long)NULL);
ClearPagePrivate(data_page);
unlock_page(data_page);
f2fs_release_crypto_ctx(ctx);
}
/**
* f2fs_crypt_complete() - The completion callback for page encryption
* @req: The asynchronous encryption request context
* @res: The result of the encryption operation
*/
static void f2fs_crypt_complete(struct crypto_async_request *req, int res)
{
struct f2fs_completion_result *ecr = req->data;
if (res == -EINPROGRESS)
return;
ecr->res = res;
complete(&ecr->completion);
}
typedef enum {
F2FS_DECRYPT = 0,
F2FS_ENCRYPT,
} f2fs_direction_t;
static int f2fs_page_crypto(struct inode *inode,
f2fs_direction_t rw,
pgoff_t index,
struct page *src_page,
struct page *dest_page)
{
u8 xts_tweak[F2FS_XTS_TWEAK_SIZE];
struct ablkcipher_request *req = NULL;
DECLARE_F2FS_COMPLETION_RESULT(ecr);
struct scatterlist dst, src;
struct f2fs_crypt_info *ci = F2FS_I(inode)->i_crypt_info;
struct crypto_ablkcipher *tfm = ci->ci_ctfm;
int res = 0;
req = ablkcipher_request_alloc(tfm, GFP_NOFS);
if (!req) {
printk_ratelimited(KERN_ERR
"%s: crypto_request_alloc() failed\n",
__func__);
return -ENOMEM;
}
ablkcipher_request_set_callback(
req, CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
f2fs_crypt_complete, &ecr);
BUILD_BUG_ON(F2FS_XTS_TWEAK_SIZE < sizeof(index));
memcpy(xts_tweak, &index, sizeof(index));
memset(&xts_tweak[sizeof(index)], 0,
F2FS_XTS_TWEAK_SIZE - sizeof(index));
sg_init_table(&dst, 1);
sg_set_page(&dst, dest_page, PAGE_CACHE_SIZE, 0);
sg_init_table(&src, 1);
sg_set_page(&src, src_page, PAGE_CACHE_SIZE, 0);
ablkcipher_request_set_crypt(req, &src, &dst, PAGE_CACHE_SIZE,
xts_tweak);
if (rw == F2FS_DECRYPT)
res = crypto_ablkcipher_decrypt(req);
else
res = crypto_ablkcipher_encrypt(req);
if (res == -EINPROGRESS || res == -EBUSY) {
wait_for_completion(&ecr.completion);
res = ecr.res;
}
ablkcipher_request_free(req);
if (res) {
printk_ratelimited(KERN_ERR
"%s: crypto_ablkcipher_encrypt() returned %d\n",
__func__, res);
return res;
}
return 0;
}
static struct page *alloc_bounce_page(struct f2fs_crypto_ctx *ctx)
{
ctx->w.bounce_page = mempool_alloc(f2fs_bounce_page_pool, GFP_NOWAIT);
if (ctx->w.bounce_page == NULL)
return ERR_PTR(-ENOMEM);
ctx->flags |= F2FS_WRITE_PATH_FL;
return ctx->w.bounce_page;
}
/**
* f2fs_encrypt() - Encrypts a page
* @inode: The inode for which the encryption should take place
* @plaintext_page: The page to encrypt. Must be locked.
*
* Allocates a ciphertext page and encrypts plaintext_page into it using the ctx
* encryption context.
*
* Called on the page write path. The caller must call
* f2fs_restore_control_page() on the returned ciphertext page to
* release the bounce buffer and the encryption context.
*
* Return: An allocated page with the encrypted content on success. Else, an
* error value or NULL.
*/
struct page *f2fs_encrypt(struct inode *inode,
struct page *plaintext_page)
{
struct f2fs_crypto_ctx *ctx;
struct page *ciphertext_page = NULL;
int err;
BUG_ON(!PageLocked(plaintext_page));
ctx = f2fs_get_crypto_ctx(inode);
if (IS_ERR(ctx))
return (struct page *)ctx;
/* The encryption operation will require a bounce page. */
ciphertext_page = alloc_bounce_page(ctx);
if (IS_ERR(ciphertext_page))
goto err_out;
ctx->w.control_page = plaintext_page;
err = f2fs_page_crypto(inode, F2FS_ENCRYPT, plaintext_page->index,
plaintext_page, ciphertext_page);
if (err) {
ciphertext_page = ERR_PTR(err);
goto err_out;
}
SetPagePrivate(ciphertext_page);
set_page_private(ciphertext_page, (unsigned long)ctx);
lock_page(ciphertext_page);
return ciphertext_page;
err_out:
f2fs_release_crypto_ctx(ctx);
return ciphertext_page;
}
/**
* f2fs_decrypt() - Decrypts a page in-place
* @ctx: The encryption context.
* @page: The page to decrypt. Must be locked.
*
* Decrypts page in-place using the ctx encryption context.
*
* Called from the read completion callback.
*
* Return: Zero on success, non-zero otherwise.
*/
int f2fs_decrypt(struct page *page)
{
BUG_ON(!PageLocked(page));
return f2fs_page_crypto(page->mapping->host,
F2FS_DECRYPT, page->index, page, page);
}
bool f2fs_valid_contents_enc_mode(uint32_t mode)
{
return (mode == F2FS_ENCRYPTION_MODE_AES_256_XTS);
}
/**
* f2fs_validate_encryption_key_size() - Validate the encryption key size
* @mode: The key mode.
* @size: The key size to validate.
*
* Return: The validated key size for @mode. Zero if invalid.
*/
uint32_t f2fs_validate_encryption_key_size(uint32_t mode, uint32_t size)
{
if (size == f2fs_encryption_key_size(mode))
return size;
return 0;
}

210
fs/f2fs/crypto_policy.c
View File

@ -1,210 +0,0 @@
/*
* copied from linux/fs/ext4/crypto_policy.c
*
* Copyright (C) 2015, Google, Inc.
* Copyright (C) 2015, Motorola Mobility.
*
* This contains encryption policy functions for f2fs with some modifications
* to support f2fs-specific xattr APIs.
*
* Written by Michael Halcrow, 2015.
* Modified by Jaegeuk Kim, 2015.
*/
#include <linux/random.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/f2fs_fs.h>
#include "f2fs.h"
#include "xattr.h"
static int f2fs_inode_has_encryption_context(struct inode *inode)
{
int res = f2fs_getxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
F2FS_XATTR_NAME_ENCRYPTION_CONTEXT, NULL, 0, NULL);
return (res > 0);
}
/*
* check whether the policy is consistent with the encryption context
* for the inode
*/
static int f2fs_is_encryption_context_consistent_with_policy(
struct inode *inode, const struct f2fs_encryption_policy *policy)
{
struct f2fs_encryption_context ctx;
int res = f2fs_getxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
F2FS_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
sizeof(ctx), NULL);
if (res != sizeof(ctx))
return 0;
return (memcmp(ctx.master_key_descriptor, policy->master_key_descriptor,
F2FS_KEY_DESCRIPTOR_SIZE) == 0 &&
(ctx.flags == policy->flags) &&
(ctx.contents_encryption_mode ==
policy->contents_encryption_mode) &&
(ctx.filenames_encryption_mode ==
policy->filenames_encryption_mode));
}
static int f2fs_create_encryption_context_from_policy(
struct inode *inode, const struct f2fs_encryption_policy *policy)
{
struct f2fs_encryption_context ctx;
ctx.format = F2FS_ENCRYPTION_CONTEXT_FORMAT_V1;
memcpy(ctx.master_key_descriptor, policy->master_key_descriptor,
F2FS_KEY_DESCRIPTOR_SIZE);
if (!f2fs_valid_contents_enc_mode(policy->contents_encryption_mode)) {
printk(KERN_WARNING
"%s: Invalid contents encryption mode %d\n", __func__,
policy->contents_encryption_mode);
return -EINVAL;
}
if (!f2fs_valid_filenames_enc_mode(policy->filenames_encryption_mode)) {
printk(KERN_WARNING
"%s: Invalid filenames encryption mode %d\n", __func__,
policy->filenames_encryption_mode);
return -EINVAL;
}
if (policy->flags & ~F2FS_POLICY_FLAGS_VALID)
return -EINVAL;
ctx.contents_encryption_mode = policy->contents_encryption_mode;
ctx.filenames_encryption_mode = policy->filenames_encryption_mode;
ctx.flags = policy->flags;
BUILD_BUG_ON(sizeof(ctx.nonce) != F2FS_KEY_DERIVATION_NONCE_SIZE);
get_random_bytes(ctx.nonce, F2FS_KEY_DERIVATION_NONCE_SIZE);
return f2fs_setxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
F2FS_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
sizeof(ctx), NULL, XATTR_CREATE);
}
int f2fs_process_policy(const struct f2fs_encryption_policy *policy,
struct inode *inode)
{
if (policy->version != 0)
return -EINVAL;
if (!S_ISDIR(inode->i_mode))
return -EINVAL;
if (!f2fs_inode_has_encryption_context(inode)) {
if (!f2fs_empty_dir(inode))
return -ENOTEMPTY;
return f2fs_create_encryption_context_from_policy(inode,
policy);
}
if (f2fs_is_encryption_context_consistent_with_policy(inode, policy))
return 0;
printk(KERN_WARNING "%s: Policy inconsistent with encryption context\n",
__func__);
return -EINVAL;
}
int f2fs_get_policy(struct inode *inode, struct f2fs_encryption_policy *policy)
{
struct f2fs_encryption_context ctx;
int res;
if (!f2fs_encrypted_inode(inode))
return -ENODATA;
res = f2fs_getxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
F2FS_XATTR_NAME_ENCRYPTION_CONTEXT,
&ctx, sizeof(ctx), NULL);
if (res != sizeof(ctx))
return -ENODATA;
if (ctx.format != F2FS_ENCRYPTION_CONTEXT_FORMAT_V1)
return -EINVAL;
policy->version = 0;
policy->contents_encryption_mode = ctx.contents_encryption_mode;
policy->filenames_encryption_mode = ctx.filenames_encryption_mode;
policy->flags = ctx.flags;
memcpy(&policy->master_key_descriptor, ctx.master_key_descriptor,
F2FS_KEY_DESCRIPTOR_SIZE);
return 0;
}
int f2fs_is_child_context_consistent_with_parent(struct inode *parent,
struct inode *child)
{
struct f2fs_crypt_info *parent_ci, *child_ci;
int res;
if ((parent == NULL) || (child == NULL)) {
pr_err("parent %p child %p\n", parent, child);
BUG_ON(1);
}
/* no restrictions if the parent directory is not encrypted */
if (!f2fs_encrypted_inode(parent))
return 1;
/* if the child directory is not encrypted, this is always a problem */
if (!f2fs_encrypted_inode(child))
return 0;
res = f2fs_get_encryption_info(parent);
if (res)
return 0;
res = f2fs_get_encryption_info(child);
if (res)
return 0;
parent_ci = F2FS_I(parent)->i_crypt_info;
child_ci = F2FS_I(child)->i_crypt_info;
if (!parent_ci && !child_ci)
return 1;
if (!parent_ci || !child_ci)
return 0;
return (memcmp(parent_ci->ci_master_key,
child_ci->ci_master_key,
F2FS_KEY_DESCRIPTOR_SIZE) == 0 &&
(parent_ci->ci_data_mode == child_ci->ci_data_mode) &&
(parent_ci->ci_filename_mode == child_ci->ci_filename_mode) &&
(parent_ci->ci_flags == child_ci->ci_flags));
}
/**
* f2fs_inherit_context() - Sets a child context from its parent
* @parent: Parent inode from which the context is inherited.
* @child: Child inode that inherits the context from @parent.
*
* Return: Zero on success, non-zero otherwise
*/
int f2fs_inherit_context(struct inode *parent, struct inode *child,
struct page *ipage)
{
struct f2fs_encryption_context ctx;
struct f2fs_crypt_info *ci;
int res;
res = f2fs_get_encryption_info(parent);
if (res < 0)
return res;
ci = F2FS_I(parent)->i_crypt_info;
if (ci == NULL)
return -ENOKEY;
ctx.format = F2FS_ENCRYPTION_CONTEXT_FORMAT_V1;
ctx.contents_encryption_mode = ci->ci_data_mode;
ctx.filenames_encryption_mode = ci->ci_filename_mode;
ctx.flags = ci->ci_flags;
memcpy(ctx.master_key_descriptor, ci->ci_master_key,
F2FS_KEY_DESCRIPTOR_SIZE);
get_random_bytes(ctx.nonce, F2FS_KEY_DERIVATION_NONCE_SIZE);
return f2fs_setxattr(child, F2FS_XATTR_INDEX_ENCRYPTION,
F2FS_XATTR_NAME_ENCRYPTION_CONTEXT, &ctx,
sizeof(ctx), ipage, XATTR_CREATE);
}

31
fs/f2fs/data.c
View File

@ -34,9 +34,9 @@ static void f2fs_read_end_io(struct bio *bio)
if (f2fs_bio_encrypted(bio)) {
if (bio->bi_error) {
f2fs_release_crypto_ctx(bio->bi_private);
fscrypt_release_ctx(bio->bi_private);
} else {
f2fs_end_io_crypto_work(bio->bi_private, bio);
fscrypt_decrypt_bio_pages(bio->bi_private, bio);
return;
}
}
@ -64,7 +64,7 @@ static void f2fs_write_end_io(struct bio *bio)
bio_for_each_segment_all(bvec, bio, i) {
struct page *page = bvec->bv_page;
f2fs_restore_and_release_control_page(&page);
fscrypt_pullback_bio_page(&page, true);
if (unlikely(bio->bi_error)) {
set_bit(AS_EIO, &page->mapping->flags);
@ -129,16 +129,10 @@ static bool __has_merged_page(struct f2fs_bio_info *io, struct inode *inode,
bio_for_each_segment_all(bvec, io->bio, i) {
if (bvec->bv_page->mapping) {
if (bvec->bv_page->mapping)
target = bvec->bv_page;
} else {
struct f2fs_crypto_ctx *ctx;
/* encrypted page */
ctx = (struct f2fs_crypto_ctx *)page_private(
bvec->bv_page);
target = ctx->w.control_page;
}
else
target = fscrypt_control_page(bvec->bv_page);
if (inode && inode == target->mapping->host)
return true;
@ -220,7 +214,8 @@ void f2fs_flush_merged_bios(struct f2fs_sb_info *sbi)
int f2fs_submit_page_bio(struct f2fs_io_info *fio)
{
struct bio *bio;
struct page *page = fio->encrypted_page ? fio->encrypted_page : fio->page;
struct page *page = fio->encrypted_page ?
fio->encrypted_page : fio->page;
trace_f2fs_submit_page_bio(page, fio);
f2fs_trace_ios(fio, 0);
@ -992,12 +987,12 @@ submit_and_realloc:
bio = NULL;
}
if (bio == NULL) {
struct f2fs_crypto_ctx *ctx = NULL;
struct fscrypt_ctx *ctx = NULL;
if (f2fs_encrypted_inode(inode) &&
S_ISREG(inode->i_mode)) {
ctx = f2fs_get_crypto_ctx(inode);
ctx = fscrypt_get_ctx(inode);
if (IS_ERR(ctx))
goto set_error_page;
@ -1010,7 +1005,7 @@ submit_and_realloc:
min_t(int, nr_pages, BIO_MAX_PAGES));
if (!bio) {
if (ctx)
f2fs_release_crypto_ctx(ctx);
fscrypt_release_ctx(ctx);
goto set_error_page;
}
bio->bi_bdev = bdev;
@ -1102,7 +1097,7 @@ int do_write_data_page(struct f2fs_io_info *fio)
f2fs_wait_on_encrypted_page_writeback(F2FS_I_SB(inode),
fio->old_blkaddr);
fio->encrypted_page = f2fs_encrypt(inode, fio->page);
fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page);
if (IS_ERR(fio->encrypted_page)) {
err = PTR_ERR(fio->encrypted_page);
goto out_writepage;
@ -1608,7 +1603,7 @@ repeat:
/* avoid symlink page */
if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
err = f2fs_decrypt(page);
err = fscrypt_decrypt_page(page);
if (err)
goto fail;
}

44
fs/f2fs/dir.c
View File

@ -77,7 +77,7 @@ static unsigned long dir_block_index(unsigned int level,
}
static struct f2fs_dir_entry *find_in_block(struct page *dentry_page,
struct f2fs_filename *fname,
struct fscrypt_name *fname,
f2fs_hash_t namehash,
int *max_slots,
struct page **res_page)
@ -103,15 +103,15 @@ static struct f2fs_dir_entry *find_in_block(struct page *dentry_page,
return de;
}
struct f2fs_dir_entry *find_target_dentry(struct f2fs_filename *fname,
struct f2fs_dir_entry *find_target_dentry(struct fscrypt_name *fname,
f2fs_hash_t namehash, int *max_slots,
struct f2fs_dentry_ptr *d)
{
struct f2fs_dir_entry *de;
unsigned long bit_pos = 0;
int max_len = 0;
struct f2fs_str de_name = FSTR_INIT(NULL, 0);
struct f2fs_str *name = &fname->disk_name;
struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
struct fscrypt_str *name = &fname->disk_name;
if (max_slots)
*max_slots = 0;
@ -157,7 +157,7 @@ found:
static struct f2fs_dir_entry *find_in_level(struct inode *dir,
unsigned int level,
struct f2fs_filename *fname,
struct fscrypt_name *fname,
struct page **res_page)
{
struct qstr name = FSTR_TO_QSTR(&fname->disk_name);
@ -218,12 +218,12 @@ struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
struct f2fs_dir_entry *de = NULL;
unsigned int max_depth;
unsigned int level;
struct f2fs_filename fname;
struct fscrypt_name fname;
int err;
*res_page = NULL;
err = f2fs_fname_setup_filename(dir, child, 1, &fname);
err = fscrypt_setup_filename(dir, child, 1, &fname);
if (err)
return NULL;
@ -251,7 +251,7 @@ struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir,
break;
}
out:
f2fs_fname_free_filename(&fname);
fscrypt_free_filename(&fname);
return de;
}
@ -413,7 +413,7 @@ struct page *init_inode_metadata(struct inode *inode, struct inode *dir,
goto put_error;
if (f2fs_encrypted_inode(dir) && f2fs_may_encrypt(inode)) {
err = f2fs_inherit_context(dir, inode, page);
err = fscrypt_inherit_context(dir, inode, page, false);
if (err)
goto put_error;
}
@ -536,11 +536,11 @@ int __f2fs_add_link(struct inode *dir, const struct qstr *name,
struct f2fs_dentry_block *dentry_blk = NULL;
struct f2fs_dentry_ptr d;
struct page *page = NULL;
struct f2fs_filename fname;
struct fscrypt_name fname;
struct qstr new_name;
int slots, err;
err = f2fs_fname_setup_filename(dir, name, 0, &fname);
err = fscrypt_setup_filename(dir, name, 0, &fname);
if (err)
return err;
@ -639,7 +639,7 @@ fail:
kunmap(dentry_page);
f2fs_put_page(dentry_page, 1);
out:
f2fs_fname_free_filename(&fname);
fscrypt_free_filename(&fname);
f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
return err;
}
@ -781,12 +781,12 @@ bool f2fs_empty_dir(struct inode *dir)
}
bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
unsigned int start_pos, struct f2fs_str *fstr)
unsigned int start_pos, struct fscrypt_str *fstr)
{
unsigned char d_type = DT_UNKNOWN;
unsigned int bit_pos;
struct f2fs_dir_entry *de = NULL;
struct f2fs_str de_name = FSTR_INIT(NULL, 0);
struct fscrypt_str de_name = FSTR_INIT(NULL, 0);
bit_pos = ((unsigned long)ctx->pos % d->max);
@ -820,8 +820,9 @@ bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d,
memcpy(de_name.name, d->filename[bit_pos], de_name.len);
ret = f2fs_fname_disk_to_usr(d->inode, &de->hash_code,
&de_name, fstr);
ret = fscrypt_fname_disk_to_usr(d->inode,
(u32)de->hash_code, 0,
&de_name, fstr);
kfree(de_name.name);
if (ret < 0)
return true;
@ -849,16 +850,15 @@ static int f2fs_readdir(struct file *file, struct dir_context *ctx)
struct file_ra_state *ra = &file->f_ra;
unsigned int n = ((unsigned long)ctx->pos / NR_DENTRY_IN_BLOCK);
struct f2fs_dentry_ptr d;
struct f2fs_str fstr = FSTR_INIT(NULL, 0);
struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
int err = 0;
if (f2fs_encrypted_inode(inode)) {
err = f2fs_get_encryption_info(inode);
err = fscrypt_get_encryption_info(inode);
if (err)
return err;
err = f2fs_fname_crypto_alloc_buffer(inode, F2FS_NAME_LEN,
&fstr);
err = fscrypt_fname_alloc_buffer(inode, F2FS_NAME_LEN, &fstr);
if (err < 0)
return err;
}
@ -898,14 +898,14 @@ static int f2fs_readdir(struct file *file, struct dir_context *ctx)
f2fs_put_page(dentry_page, 1);
}
out:
f2fs_fname_crypto_free_buffer(&fstr);
fscrypt_fname_free_buffer(&fstr);
return err;
}
static int f2fs_dir_open(struct inode *inode, struct file *filp)
{
if (f2fs_encrypted_inode(inode))
return f2fs_get_encryption_info(inode) ? -EACCES : 0;
return fscrypt_get_encryption_info(inode) ? -EACCES : 0;
return 0;
}

172
fs/f2fs/f2fs.h
View File

@ -22,6 +22,7 @@
#include <linux/vmalloc.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/fscrypto.h>
#ifdef CONFIG_F2FS_CHECK_FS
#define f2fs_bug_on(sbi, condition) BUG_ON(condition)
@ -231,12 +232,9 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal,
#define F2FS_IOC_WRITE_CHECKPOINT _IO(F2FS_IOCTL_MAGIC, 7)
#define F2FS_IOC_DEFRAGMENT _IO(F2FS_IOCTL_MAGIC, 8)
#define F2FS_IOC_SET_ENCRYPTION_POLICY \
_IOR('f', 19, struct f2fs_encryption_policy)
#define F2FS_IOC_GET_ENCRYPTION_PWSALT \
_IOW('f', 20, __u8[16])
#define F2FS_IOC_GET_ENCRYPTION_POLICY \
_IOW('f', 21, struct f2fs_encryption_policy)
#define F2FS_IOC_SET_ENCRYPTION_POLICY FS_IOC_SET_ENCRYPTION_POLICY
#define F2FS_IOC_GET_ENCRYPTION_POLICY FS_IOC_GET_ENCRYPTION_POLICY
#define F2FS_IOC_GET_ENCRYPTION_PWSALT FS_IOC_GET_ENCRYPTION_PWSALT
/*
* should be same as XFS_IOC_GOINGDOWN.
@ -266,25 +264,6 @@ struct f2fs_defragment {
* For INODE and NODE manager
*/
/* for directory operations */
struct f2fs_str {
unsigned char *name;
u32 len;
};
struct f2fs_filename {
const struct qstr *usr_fname;
struct f2fs_str disk_name;
f2fs_hash_t hash;
#ifdef CONFIG_F2FS_FS_ENCRYPTION
struct f2fs_str crypto_buf;
#endif
};
#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)
struct f2fs_dentry_ptr {
struct inode *inode;
const void *bitmap;
@ -412,15 +391,6 @@ struct f2fs_map_blocks {
#define file_enc_name(inode) is_file(inode, FADVISE_ENC_NAME_BIT)
#define file_set_enc_name(inode) set_file(inode, FADVISE_ENC_NAME_BIT)
/* Encryption algorithms */
#define F2FS_ENCRYPTION_MODE_INVALID 0
#define F2FS_ENCRYPTION_MODE_AES_256_XTS 1
#define F2FS_ENCRYPTION_MODE_AES_256_GCM 2
#define F2FS_ENCRYPTION_MODE_AES_256_CBC 3
#define F2FS_ENCRYPTION_MODE_AES_256_CTS 4
#include "f2fs_crypto.h"
#define DEF_DIR_LEVEL 0
struct f2fs_inode_info {
@ -444,13 +414,7 @@ struct f2fs_inode_info {
struct list_head dirty_list; /* linked in global dirty list */
struct list_head inmem_pages; /* inmemory pages managed by f2fs */
struct mutex inmem_lock; /* lock for inmemory pages */
struct extent_tree *extent_tree; /* cached extent_tree entry */
#ifdef CONFIG_F2FS_FS_ENCRYPTION
/* Encryption params */
struct f2fs_crypt_info *i_crypt_info;
#endif
};
static inline void get_extent_info(struct extent_info *ext,
@ -1741,10 +1705,10 @@ struct dentry *f2fs_get_parent(struct dentry *child);
extern unsigned char f2fs_filetype_table[F2FS_FT_MAX];
void set_de_type(struct f2fs_dir_entry *, umode_t);
struct f2fs_dir_entry *find_target_dentry(struct f2fs_filename *,
struct f2fs_dir_entry *find_target_dentry(struct fscrypt_name *,
f2fs_hash_t, int *, struct f2fs_dentry_ptr *);
bool f2fs_fill_dentries(struct dir_context *, struct f2fs_dentry_ptr *,
unsigned int, struct f2fs_str *);
unsigned int, struct fscrypt_str *);
void do_make_empty_dir(struct inode *, struct inode *,
struct f2fs_dentry_ptr *);
struct page *init_inode_metadata(struct inode *, struct inode *,
@ -2120,7 +2084,7 @@ int f2fs_convert_inline_inode(struct inode *);
int f2fs_write_inline_data(struct inode *, struct page *);
bool recover_inline_data(struct inode *, struct page *);
struct f2fs_dir_entry *find_in_inline_dir(struct inode *,
struct f2fs_filename *, struct page **);
struct fscrypt_name *, struct page **);
struct f2fs_dir_entry *f2fs_parent_inline_dir(struct inode *, struct page **);
int make_empty_inline_dir(struct inode *inode, struct inode *, struct page *);
int f2fs_add_inline_entry(struct inode *, const struct qstr *, struct inode *,
@ -2129,7 +2093,7 @@ void f2fs_delete_inline_entry(struct f2fs_dir_entry *, struct page *,
struct inode *, struct inode *);
bool f2fs_empty_inline_dir(struct inode *);
int f2fs_read_inline_dir(struct file *, struct dir_context *,
struct f2fs_str *);
struct fscrypt_str *);
int f2fs_inline_data_fiemap(struct inode *,
struct fiemap_extent_info *, __u64, __u64);
@ -2159,13 +2123,9 @@ void destroy_extent_cache(void);
/*
* crypto support
*/
static inline int f2fs_encrypted_inode(struct inode *inode)
static inline bool f2fs_encrypted_inode(struct inode *inode)
{
#ifdef CONFIG_F2FS_FS_ENCRYPTION
return file_is_encrypt(inode);
#else
return 0;
#endif
}
static inline void f2fs_set_encrypted_inode(struct inode *inode)
@ -2177,20 +2137,12 @@ static inline void f2fs_set_encrypted_inode(struct inode *inode)
static inline bool f2fs_bio_encrypted(struct bio *bio)
{
#ifdef CONFIG_F2FS_FS_ENCRYPTION
return unlikely(bio->bi_private != NULL);
#else
return false;
#endif
return bio->bi_private != NULL;
}
static inline int f2fs_sb_has_crypto(struct super_block *sb)
{
#ifdef CONFIG_F2FS_FS_ENCRYPTION
return F2FS_HAS_FEATURE(sb, F2FS_FEATURE_ENCRYPT);
#else
return 0;
#endif
}
static inline bool f2fs_may_encrypt(struct inode *inode)
@ -2204,86 +2156,28 @@ static inline bool f2fs_may_encrypt(struct inode *inode)
#endif
}
/* crypto_policy.c */
int f2fs_is_child_context_consistent_with_parent(struct inode *,
struct inode *);
int f2fs_inherit_context(struct inode *, struct inode *, struct page *);
int f2fs_process_policy(const struct f2fs_encryption_policy *, struct inode *);
int f2fs_get_policy(struct inode *, struct f2fs_encryption_policy *);
/* crypt.c */
extern struct kmem_cache *f2fs_crypt_info_cachep;
bool f2fs_valid_contents_enc_mode(uint32_t);
uint32_t f2fs_validate_encryption_key_size(uint32_t, uint32_t);
struct f2fs_crypto_ctx *f2fs_get_crypto_ctx(struct inode *);
void f2fs_release_crypto_ctx(struct f2fs_crypto_ctx *);
struct page *f2fs_encrypt(struct inode *, struct page *);
int f2fs_decrypt(struct page *);
void f2fs_end_io_crypto_work(struct f2fs_crypto_ctx *, struct bio *);
/* crypto_key.c */
void f2fs_free_encryption_info(struct inode *, struct f2fs_crypt_info *);
int _f2fs_get_encryption_info(struct inode *inode);
/* crypto_fname.c */
bool f2fs_valid_filenames_enc_mode(uint32_t);
u32 f2fs_fname_crypto_round_up(u32, u32);
unsigned f2fs_fname_encrypted_size(struct inode *, u32);
int f2fs_fname_crypto_alloc_buffer(struct inode *, u32, struct f2fs_str *);
int f2fs_fname_disk_to_usr(struct inode *, f2fs_hash_t *,
const struct f2fs_str *, struct f2fs_str *);
int f2fs_fname_usr_to_disk(struct inode *, const struct qstr *,
struct f2fs_str *);
#ifdef CONFIG_F2FS_FS_ENCRYPTION
void f2fs_restore_and_release_control_page(struct page **);
void f2fs_restore_control_page(struct page *);
int __init f2fs_init_crypto(void);
int f2fs_crypto_initialize(void);
void f2fs_exit_crypto(void);
int f2fs_has_encryption_key(struct inode *);
static inline int f2fs_get_encryption_info(struct inode *inode)
{
struct f2fs_crypt_info *ci = F2FS_I(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 _f2fs_get_encryption_info(inode);
return 0;
}
void f2fs_fname_crypto_free_buffer(struct f2fs_str *);
int f2fs_fname_setup_filename(struct inode *, const struct qstr *,
int lookup, struct f2fs_filename *);
void f2fs_fname_free_filename(struct f2fs_filename *);
#else
static inline void f2fs_restore_and_release_control_page(struct page **p) { }
static inline void f2fs_restore_control_page(struct page *p) { }
static inline int __init f2fs_init_crypto(void) { return 0; }
static inline void f2fs_exit_crypto(void) { }
static inline int f2fs_has_encryption_key(struct inode *i) { return 0; }
static inline int f2fs_get_encryption_info(struct inode *i) { return 0; }
static inline void f2fs_fname_crypto_free_buffer(struct f2fs_str *p) { }
static inline int f2fs_fname_setup_filename(struct inode *dir,
const struct qstr *iname,
int lookup, struct f2fs_filename *fname)
{
memset(fname, 0, sizeof(struct f2fs_filename));
fname->usr_fname = iname;
fname->disk_name.name = (unsigned char *)iname->name;
fname->disk_name.len = iname->len;
return 0;
}
static inline void f2fs_fname_free_filename(struct f2fs_filename *fname) { }
#ifndef CONFIG_F2FS_FS_ENCRYPTION
#define fscrypt_set_d_op(i)
#define fscrypt_get_ctx fscrypt_notsupp_get_ctx
#define fscrypt_release_ctx fscrypt_notsupp_release_ctx
#define fscrypt_encrypt_page fscrypt_notsupp_encrypt_page
#define fscrypt_decrypt_page fscrypt_notsupp_decrypt_page
#define fscrypt_decrypt_bio_pages fscrypt_notsupp_decrypt_bio_pages
#define fscrypt_pullback_bio_page fscrypt_notsupp_pullback_bio_page
#define fscrypt_restore_control_page fscrypt_notsupp_restore_control_page
#define fscrypt_zeroout_range fscrypt_notsupp_zeroout_range
#define fscrypt_process_policy fscrypt_notsupp_process_policy
#define fscrypt_get_policy fscrypt_notsupp_get_policy
#define fscrypt_has_permitted_context fscrypt_notsupp_has_permitted_context
#define fscrypt_inherit_context fscrypt_notsupp_inherit_context
#define fscrypt_get_encryption_info fscrypt_notsupp_get_encryption_info
#define fscrypt_put_encryption_info fscrypt_notsupp_put_encryption_info
#define fscrypt_setup_filename fscrypt_notsupp_setup_filename
#define fscrypt_free_filename fscrypt_notsupp_free_filename
#define fscrypt_fname_encrypted_size fscrypt_notsupp_fname_encrypted_size
#define fscrypt_fname_alloc_buffer fscrypt_notsupp_fname_alloc_buffer
#define fscrypt_fname_free_buffer fscrypt_notsupp_fname_free_buffer
#define fscrypt_fname_disk_to_usr fscrypt_notsupp_fname_disk_to_usr
#define fscrypt_fname_usr_to_disk fscrypt_notsupp_fname_usr_to_disk
#endif
#endif

151
fs/f2fs/f2fs_crypto.h
View File

@ -1,151 +0,0 @@
/*
* linux/fs/f2fs/f2fs_crypto.h
*
* Copied from linux/fs/ext4/ext4_crypto.h
*
* Copyright (C) 2015, Google, Inc.
*
* This contains encryption header content for f2fs
*
* Written by Michael Halcrow, 2015.
* Modified by Jaegeuk Kim, 2015.
*/
#ifndef _F2FS_CRYPTO_H
#define _F2FS_CRYPTO_H
#include <linux/fs.h>
#define F2FS_KEY_DESCRIPTOR_SIZE 8
/* Policy provided via an ioctl on the topmost directory */
struct f2fs_encryption_policy {
char version;
char contents_encryption_mode;
char filenames_encryption_mode;
char flags;
char master_key_descriptor[F2FS_KEY_DESCRIPTOR_SIZE];
} __attribute__((__packed__));
#define F2FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
#define F2FS_KEY_DERIVATION_NONCE_SIZE 16
#define F2FS_POLICY_FLAGS_PAD_4 0x00
#define F2FS_POLICY_FLAGS_PAD_8 0x01
#define F2FS_POLICY_FLAGS_PAD_16 0x02
#define F2FS_POLICY_FLAGS_PAD_32 0x03
#define F2FS_POLICY_FLAGS_PAD_MASK 0x03
#define F2FS_POLICY_FLAGS_VALID 0x03
/**
* 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 f2fs_encryption_context {
char format;
char contents_encryption_mode;
char filenames_encryption_mode;
char flags;
char master_key_descriptor[F2FS_KEY_DESCRIPTOR_SIZE];
char nonce[F2FS_KEY_DERIVATION_NONCE_SIZE];
} __attribute__((__packed__));
/* Encryption parameters */
#define F2FS_XTS_TWEAK_SIZE 16
#define F2FS_AES_128_ECB_KEY_SIZE 16
#define F2FS_AES_256_GCM_KEY_SIZE 32
#define F2FS_AES_256_CBC_KEY_SIZE 32
#define F2FS_AES_256_CTS_KEY_SIZE 32
#define F2FS_AES_256_XTS_KEY_SIZE 64
#define F2FS_MAX_KEY_SIZE 64
#define F2FS_KEY_DESC_PREFIX "f2fs:"
#define F2FS_KEY_DESC_PREFIX_SIZE 5
struct f2fs_encryption_key {
__u32 mode;
char raw[F2FS_MAX_KEY_SIZE];
__u32 size;
} __attribute__((__packed__));
struct f2fs_crypt_info {
char ci_data_mode;
char ci_filename_mode;
char ci_flags;
struct crypto_ablkcipher *ci_ctfm;
struct key *ci_keyring_key;
char ci_master_key[F2FS_KEY_DESCRIPTOR_SIZE];
};
#define F2FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
#define F2FS_WRITE_PATH_FL 0x00000002
struct f2fs_crypto_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 */
};
char flags; /* Flags */
};
struct f2fs_completion_result {
struct completion completion;
int res;
};
#define DECLARE_F2FS_COMPLETION_RESULT(ecr) \
struct f2fs_completion_result ecr = { \
COMPLETION_INITIALIZER((ecr).completion), 0 }
static inline int f2fs_encryption_key_size(int mode)
{
switch (mode) {
case F2FS_ENCRYPTION_MODE_AES_256_XTS:
return F2FS_AES_256_XTS_KEY_SIZE;
case F2FS_ENCRYPTION_MODE_AES_256_GCM:
return F2FS_AES_256_GCM_KEY_SIZE;
case F2FS_ENCRYPTION_MODE_AES_256_CBC:
return F2FS_AES_256_CBC_KEY_SIZE;
case F2FS_ENCRYPTION_MODE_AES_256_CTS:
return F2FS_AES_256_CTS_KEY_SIZE;
default:
BUG();
}
return 0;
}
#define F2FS_FNAME_NUM_SCATTER_ENTRIES 4
#define F2FS_CRYPTO_BLOCK_SIZE 16
#define F2FS_FNAME_CRYPTO_DIGEST_SIZE 32
/**
* For encrypted symlinks, the ciphertext length is stored at the beginning
* of the string in little-endian format.
*/
struct f2fs_encrypted_symlink_data {
__le16 len;
char encrypted_path[1];
} __attribute__((__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 encrypted_symlink_data_len(u32 l)
{
return (l + sizeof(struct f2fs_encrypted_symlink_data) - 1);
}
#endif /* _F2FS_CRYPTO_H */

38
fs/f2fs/file.c
View File

@ -421,7 +421,7 @@ static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
int err;
if (f2fs_encrypted_inode(inode)) {
err = f2fs_get_encryption_info(inode);
err = fscrypt_get_encryption_info(inode);
if (err)
return 0;
if (!f2fs_encrypted_inode(inode))
@ -443,10 +443,10 @@ static int f2fs_file_open(struct inode *inode, struct file *filp)
int ret = generic_file_open(inode, filp);
if (!ret && f2fs_encrypted_inode(inode)) {
ret = f2fs_get_encryption_info(inode);
ret = fscrypt_get_encryption_info(inode);
if (ret)
return -EACCES;
if (!f2fs_encrypted_inode(inode))
if (!fscrypt_has_encryption_key(inode))
return -ENOKEY;
}
return ret;
@ -526,7 +526,8 @@ static int truncate_partial_data_page(struct inode *inode, u64 from,
truncate_out:
f2fs_wait_on_page_writeback(page, DATA, true);
zero_user(page, offset, PAGE_CACHE_SIZE - offset);
if (!cache_only || !f2fs_encrypted_inode(inode) || !S_ISREG(inode->i_mode))
if (!cache_only || !f2fs_encrypted_inode(inode) ||
!S_ISREG(inode->i_mode))
set_page_dirty(page);
f2fs_put_page(page, 1);
return 0;
@ -674,7 +675,7 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
if (attr->ia_valid & ATTR_SIZE) {
if (f2fs_encrypted_inode(inode) &&
f2fs_get_encryption_info(inode))
fscrypt_get_encryption_info(inode))
return -EACCES;
if (attr->ia_size <= i_size_read(inode)) {
@ -1529,39 +1530,30 @@ static bool uuid_is_nonzero(__u8 u[16])
static int f2fs_ioc_set_encryption_policy(struct file *filp, unsigned long arg)
{
#ifdef CONFIG_F2FS_FS_ENCRYPTION
struct f2fs_encryption_policy policy;
struct fscrypt_policy policy;
struct inode *inode = file_inode(filp);
if (copy_from_user(&policy, (struct f2fs_encryption_policy __user *)arg,
sizeof(policy)))
if (copy_from_user(&policy, (struct fscrypt_policy __user *)arg,
sizeof(policy)))
return -EFAULT;
f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
return f2fs_process_policy(&policy, inode);
#else
return -EOPNOTSUPP;
#endif
return fscrypt_process_policy(inode, &policy);
}
static int f2fs_ioc_get_encryption_policy(struct file *filp, unsigned long arg)
{
#ifdef CONFIG_F2FS_FS_ENCRYPTION
struct f2fs_encryption_policy policy;
struct fscrypt_policy policy;
struct inode *inode = file_inode(filp);
int err;
err = f2fs_get_policy(inode, &policy);
err = fscrypt_get_policy(inode, &policy);
if (err)
return err;
if (copy_to_user((struct f2fs_encryption_policy __user *)arg, &policy,
sizeof(policy)))
if (copy_to_user((struct fscrypt_policy __user *)arg, &policy, sizeof(policy)))
return -EFAULT;
return 0;
#else
return -EOPNOTSUPP;
#endif
}
static int f2fs_ioc_get_encryption_pwsalt(struct file *filp, unsigned long arg)
@ -1873,8 +1865,8 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
ssize_t ret;
if (f2fs_encrypted_inode(inode) &&
!f2fs_has_encryption_key(inode) &&
f2fs_get_encryption_info(inode))
!fscrypt_has_encryption_key(inode) &&
fscrypt_get_encryption_info(inode))
return -EACCES;
inode_lock(inode);

4
fs/f2fs/inline.c
View File

@ -277,7 +277,7 @@ process_inline:
}
struct f2fs_dir_entry *find_in_inline_dir(struct inode *dir,
struct f2fs_filename *fname, struct page **res_page)
struct fscrypt_name *fname, struct page **res_page)
{
struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);
struct f2fs_inline_dentry *inline_dentry;
@ -535,7 +535,7 @@ bool f2fs_empty_inline_dir(struct inode *dir)
}
int f2fs_read_inline_dir(struct file *file, struct dir_context *ctx,
struct f2fs_str *fstr)
struct fscrypt_str *fstr)
{
struct inode *inode = file_inode(file);
struct f2fs_inline_dentry *inline_dentry = NULL;

5
fs/f2fs/inode.c
View File

@ -389,10 +389,7 @@ no_delete:
}
}
out_clear:
#ifdef CONFIG_F2FS_FS_ENCRYPTION
if (fi->i_crypt_info)
f2fs_free_encryption_info(inode, fi->i_crypt_info);
#endif
fscrypt_put_encryption_info(inode, NULL);
clear_inode(inode);
}

56
fs/f2fs/namei.c
View File

@ -169,7 +169,7 @@ static int f2fs_link(struct dentry *old_dentry, struct inode *dir,
int err;
if (f2fs_encrypted_inode(dir) &&
!f2fs_is_child_context_consistent_with_parent(dir, inode))
!fscrypt_has_permitted_context(dir, inode))
return -EPERM;
f2fs_balance_fs(sbi, true);
@ -352,20 +352,20 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
struct inode *inode;
size_t len = strlen(symname);
struct f2fs_str disk_link = FSTR_INIT((char *)symname, len + 1);
struct f2fs_encrypted_symlink_data *sd = NULL;
struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1);
struct fscrypt_symlink_data *sd = NULL;
int err;
if (f2fs_encrypted_inode(dir)) {
err = f2fs_get_encryption_info(dir);
err = fscrypt_get_encryption_info(dir);
if (err)
return err;
if (!f2fs_encrypted_inode(dir))
if (!fscrypt_has_encryption_key(dir))
return -EPERM;
disk_link.len = (f2fs_fname_encrypted_size(dir, len) +
sizeof(struct f2fs_encrypted_symlink_data));
disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
sizeof(struct fscrypt_symlink_data));
}
if (disk_link.len > dir->i_sb->s_blocksize)
@ -393,7 +393,7 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
if (f2fs_encrypted_inode(inode)) {
struct qstr istr = QSTR_INIT(symname, len);
struct f2fs_str ostr;
struct fscrypt_str ostr;
sd = kzalloc(disk_link.len, GFP_NOFS);
if (!sd) {
@ -401,18 +401,18 @@ static int f2fs_symlink(struct inode *dir, struct dentry *dentry,
goto err_out;
}
err = f2fs_get_encryption_info(inode);
err = fscrypt_get_encryption_info(inode);
if (err)
goto err_out;
if (!f2fs_encrypted_inode(inode)) {
if (!fscrypt_has_encryption_key(inode)) {
err = -EPERM;
goto err_out;
}
ostr.name = sd->encrypted_path;
ostr.len = disk_link.len;
err = f2fs_fname_usr_to_disk(inode, &istr, &ostr);
err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr);
if (err < 0)
goto err_out;
@ -593,7 +593,7 @@ out:
static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
{
if (f2fs_encrypted_inode(dir)) {
int err = f2fs_get_encryption_info(dir);
int err = fscrypt_get_encryption_info(dir);
if (err)
return err;
}
@ -623,8 +623,7 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
int err = -ENOENT;
if ((old_dir != new_dir) && f2fs_encrypted_inode(new_dir) &&
!f2fs_is_child_context_consistent_with_parent(new_dir,
old_inode)) {
!fscrypt_has_permitted_context(new_dir, old_inode)) {
err = -EPERM;
goto out;
}
@ -804,11 +803,9 @@ static int f2fs_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
int err = -ENOENT;
if ((f2fs_encrypted_inode(old_dir) || f2fs_encrypted_inode(new_dir)) &&
(old_dir != new_dir) &&
(!f2fs_is_child_context_consistent_with_parent(new_dir,
old_inode) ||
!f2fs_is_child_context_consistent_with_parent(old_dir,
new_inode)))
(old_dir != new_dir) &&
(!fscrypt_has_permitted_context(new_dir, old_inode) ||
!fscrypt_has_permitted_context(old_dir, new_inode)))
return -EPERM;
old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
@ -970,16 +967,15 @@ static int f2fs_rename2(struct inode *old_dir, struct dentry *old_dentry,
return f2fs_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
}
#ifdef CONFIG_F2FS_FS_ENCRYPTION
static const char *f2fs_encrypted_get_link(struct dentry *dentry,
struct inode *inode,
struct delayed_call *done)
{
struct page *cpage = NULL;
char *caddr, *paddr = NULL;
struct f2fs_str cstr = FSTR_INIT(NULL, 0);
struct f2fs_str pstr = FSTR_INIT(NULL, 0);
struct f2fs_encrypted_symlink_data *sd;
struct fscrypt_str cstr = FSTR_INIT(NULL, 0);
struct fscrypt_str pstr = FSTR_INIT(NULL, 0);
struct fscrypt_symlink_data *sd;
loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1);
u32 max_size = inode->i_sb->s_blocksize;
int res;
@ -987,7 +983,7 @@ static const char *f2fs_encrypted_get_link(struct dentry *dentry,
if (!dentry)
return ERR_PTR(-ECHILD);
res = f2fs_get_encryption_info(inode);
res = fscrypt_get_encryption_info(inode);
if (res)
return ERR_PTR(res);
@ -998,7 +994,7 @@ static const char *f2fs_encrypted_get_link(struct dentry *dentry,
caddr[size] = 0;
/* Symlink is encrypted */
sd = (struct f2fs_encrypted_symlink_data *)caddr;
sd = (struct fscrypt_symlink_data *)caddr;
cstr.name = sd->encrypted_path;
cstr.len = le16_to_cpu(sd->len);
@ -1014,17 +1010,16 @@ static const char *f2fs_encrypted_get_link(struct dentry *dentry,
goto errout;
}
if ((cstr.len + sizeof(struct f2fs_encrypted_symlink_data) - 1) >
max_size) {
if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) {
/* Symlink data on the disk is corrupted */
res = -EIO;
goto errout;
}
res = f2fs_fname_crypto_alloc_buffer(inode, cstr.len, &pstr);
res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr);
if (res)
goto errout;
res = f2fs_fname_disk_to_usr(inode, NULL, &cstr, &pstr);
res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr);
if (res < 0)
goto errout;
@ -1037,7 +1032,7 @@ static const char *f2fs_encrypted_get_link(struct dentry *dentry,
set_delayed_call(done, kfree_link, paddr);
return paddr;
errout:
f2fs_fname_crypto_free_buffer(&pstr);
fscrypt_fname_free_buffer(&pstr);
page_cache_release(cpage);
return ERR_PTR(res);
}
@ -1054,7 +1049,6 @@ const struct inode_operations f2fs_encrypted_symlink_inode_operations = {
.removexattr = generic_removexattr,
#endif
};
#endif
const struct inode_operations f2fs_dir_inode_operations = {
.create = f2fs_create,

55
fs/f2fs/super.c
View File

@ -470,10 +470,6 @@ static struct inode *f2fs_alloc_inode(struct super_block *sb)
/* Will be used by directory only */
fi->i_dir_level = F2FS_SB(sb)->dir_level;
#ifdef CONFIG_F2FS_FS_ENCRYPTION
fi->i_crypt_info = NULL;
#endif
return &fi->vfs_inode;
}
@ -507,11 +503,7 @@ static int f2fs_drop_inode(struct inode *inode)
sb_end_intwrite(inode->i_sb);
#ifdef CONFIG_F2FS_FS_ENCRYPTION
if (F2FS_I(inode)->i_crypt_info)
f2fs_free_encryption_info(inode,
F2FS_I(inode)->i_crypt_info);
#endif
fscrypt_put_encryption_info(inode, NULL);
spin_lock(&inode->i_lock);
atomic_dec(&inode->i_count);
}
@ -891,6 +883,41 @@ static struct super_operations f2fs_sops = {
.remount_fs = f2fs_remount,
};
#ifdef CONFIG_F2FS_FS_ENCRYPTION
static int f2fs_get_context(struct inode *inode, void *ctx, size_t len)
{
return f2fs_getxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
F2FS_XATTR_NAME_ENCRYPTION_CONTEXT,
ctx, len, NULL);
}
static int f2fs_set_context(struct inode *inode, const void *ctx, size_t len,
void *fs_data)
{
return f2fs_setxattr(inode, F2FS_XATTR_INDEX_ENCRYPTION,
F2FS_XATTR_NAME_ENCRYPTION_CONTEXT,
ctx, len, fs_data, XATTR_CREATE);
}
static unsigned f2fs_max_namelen(struct inode *inode)
{
return S_ISLNK(inode->i_mode) ?
inode->i_sb->s_blocksize : F2FS_NAME_LEN;
}
static struct fscrypt_operations f2fs_cryptops = {
.get_context = f2fs_get_context,
.set_context = f2fs_set_context,
.is_encrypted = f2fs_encrypted_inode,
.empty_dir = f2fs_empty_dir,
.max_namelen = f2fs_max_namelen,
};
#else
static struct fscrypt_operations f2fs_cryptops = {
.is_encrypted = f2fs_encrypted_inode,
};
#endif
static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
u64 ino, u32 generation)
{
@ -1314,6 +1341,7 @@ try_onemore:
get_random_bytes(&sbi->s_next_generation, sizeof(u32));
sb->s_op = &f2fs_sops;
sb->s_cop = &f2fs_cryptops;
sb->s_xattr = f2fs_xattr_handlers;
sb->s_export_op = &f2fs_export_ops;
sb->s_magic = F2FS_SUPER_MAGIC;
@ -1619,13 +1647,9 @@ static int __init init_f2fs_fs(void)
err = -ENOMEM;
goto free_extent_cache;
}
err = f2fs_init_crypto();
if (err)
goto free_kset;
err = register_shrinker(&f2fs_shrinker_info);
if (err)
goto free_crypto;
goto free_kset;
err = register_filesystem(&f2fs_fs_type);
if (err)
@ -1640,8 +1664,6 @@ free_filesystem:
unregister_filesystem(&f2fs_fs_type);
free_shrinker:
unregister_shrinker(&f2fs_shrinker_info);
free_crypto:
f2fs_exit_crypto();
free_kset:
kset_unregister(f2fs_kset);
free_extent_cache:
@ -1664,7 +1686,6 @@ static void __exit exit_f2fs_fs(void)
f2fs_destroy_root_stats();
unregister_shrinker(&f2fs_shrinker_info);
unregister_filesystem(&f2fs_fs_type);
f2fs_exit_crypto();
destroy_extent_cache();
destroy_checkpoint_caches();
destroy_segment_manager_caches();

2
include/linux/dcache.h
View File

@ -228,6 +228,8 @@ struct dentry_operations {
#define DCACHE_FALLTHRU 0x01000000 /* Fall through to lower layer */
#define DCACHE_OP_SELECT_INODE 0x02000000 /* Unioned entry: dcache op selects inode */
#define DCACHE_ENCRYPTED_WITH_KEY 0x04000000 /* dir is encrypted with a valid key */
extern seqlock_t rename_lock;
/*

8
include/linux/fs.h
View File

@ -53,6 +53,8 @@ struct swap_info_struct;
struct seq_file;
struct workqueue_struct;
struct iov_iter;
struct fscrypt_info;
struct fscrypt_operations;
extern void __init inode_init(void);
extern void __init inode_init_early(void);
@ -678,6 +680,10 @@ struct inode {
struct hlist_head i_fsnotify_marks;
#endif
#if IS_ENABLED(CONFIG_FS_ENCRYPTION)
struct fscrypt_info *i_crypt_info;
#endif
void *i_private; /* fs or device private pointer */
};
@ -1323,6 +1329,8 @@ struct super_block {
#endif
const struct xattr_handler **s_xattr;
const struct fscrypt_operations *s_cop;
struct hlist_bl_head s_anon; /* anonymous dentries for (nfs) exporting */
struct list_head s_mounts; /* list of mounts; _not_ for fs use */
struct block_device *s_bdev;

433
include/linux/fscrypto.h Normal file
View File

@ -0,0 +1,433 @@
/*
* 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 */

18
include/uapi/linux/fs.h
View File

@ -246,6 +246,24 @@ struct fsxattr {
#define FS_IOC_FSGETXATTR _IOR ('X', 31, struct fsxattr)
#define FS_IOC_FSSETXATTR _IOW ('X', 32, struct fsxattr)
/*
* File system encryption support
*/
/* Policy provided via an ioctl on the topmost directory */
#define FS_KEY_DESCRIPTOR_SIZE 8
struct fscrypt_policy {
__u8 version;
__u8 contents_encryption_mode;
__u8 filenames_encryption_mode;
__u8 flags;
__u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
} __packed;
#define FS_IOC_SET_ENCRYPTION_POLICY _IOR('f', 19, struct fscrypt_policy)
#define FS_IOC_GET_ENCRYPTION_PWSALT _IOW('f', 20, __u8[16])
#define FS_IOC_GET_ENCRYPTION_POLICY _IOW('f', 21, struct fscrypt_policy)
/*
* Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
*