Cherry-picked from origin/upstream-f2fs-stable-linux-4.14.y:tirimbino9d468a2b52Revert "locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()"13b237d115fscrypt: move to generic async completiona2985b1c98crypto: introduce crypto wait for async op4bb665c7e3locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()249c90416bfscrypt: new helper function - fscrypt_prepare_setattr()91d09c0521fscrypt: new helper function - fscrypt_prepare_lookup()9a24d618cbfscrypt: new helper function - fscrypt_prepare_rename()4bd6179f52fscrypt: new helper function - fscrypt_prepare_link()b811faac63fscrypt: new helper function - fscrypt_file_open()e9f57e3771fscrypt: new helper function - fscrypt_require_key()b31ee2e128fscrypt: remove unneeded empty fscrypt_operations structs82cbed4cdcfscrypt: remove ->is_encrypted()2edb5df148fscrypt: switch from ->is_encrypted() to IS_ENCRYPTED()cde1fbb02dfs, fscrypt: add an S_ENCRYPTED inode flag8ec05db254fscrypt: clean up include file mess Change-Id: I8980613b8d5ffedf72ef2c91e1ae2eebb521ae19 Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
Jaegeuk Kim
7 years ago
parent
45e631ea3f
commit
a53dc75af2
@ -1,4 +1,4 @@ |
||||
obj-$(CONFIG_FS_ENCRYPTION) += fscrypto.o
|
||||
|
||||
fscrypto-y := crypto.o fname.o policy.o keyinfo.o
|
||||
fscrypto-y := crypto.o fname.o hooks.o keyinfo.o policy.o
|
||||
fscrypto-$(CONFIG_BLOCK) += bio.o
|
||||
|
||||
@ -0,0 +1,112 @@ |
||||
/*
|
||||
* fs/crypto/hooks.c |
||||
* |
||||
* Encryption hooks for higher-level filesystem operations. |
||||
*/ |
||||
|
||||
#include <linux/ratelimit.h> |
||||
#include "fscrypt_private.h" |
||||
|
||||
/**
|
||||
* fscrypt_file_open - prepare to open a possibly-encrypted regular file |
||||
* @inode: the inode being opened |
||||
* @filp: the struct file being set up |
||||
* |
||||
* Currently, an encrypted regular file can only be opened if its encryption key |
||||
* is available; access to the raw encrypted contents is not supported. |
||||
* Therefore, we first set up the inode's encryption key (if not already done) |
||||
* and return an error if it's unavailable. |
||||
* |
||||
* We also verify that if the parent directory (from the path via which the file |
||||
* is being opened) is encrypted, then the inode being opened uses the same |
||||
* encryption policy. This is needed as part of the enforcement that all files |
||||
* in an encrypted directory tree use the same encryption policy, as a |
||||
* protection against certain types of offline attacks. Note that this check is |
||||
* needed even when opening an *unencrypted* file, since it's forbidden to have |
||||
* an unencrypted file in an encrypted directory. |
||||
* |
||||
* Return: 0 on success, -ENOKEY if the key is missing, or another -errno code |
||||
*/ |
||||
int fscrypt_file_open(struct inode *inode, struct file *filp) |
||||
{ |
||||
int err; |
||||
struct dentry *dir; |
||||
|
||||
err = fscrypt_require_key(inode); |
||||
if (err) |
||||
return err; |
||||
|
||||
dir = dget_parent(file_dentry(filp)); |
||||
if (IS_ENCRYPTED(d_inode(dir)) && |
||||
!fscrypt_has_permitted_context(d_inode(dir), inode)) { |
||||
pr_warn_ratelimited("fscrypt: inconsistent encryption contexts: %lu/%lu", |
||||
d_inode(dir)->i_ino, inode->i_ino); |
||||
err = -EPERM; |
||||
} |
||||
dput(dir); |
||||
return err; |
||||
} |
||||
EXPORT_SYMBOL_GPL(fscrypt_file_open); |
||||
|
||||
int __fscrypt_prepare_link(struct inode *inode, struct inode *dir) |
||||
{ |
||||
int err; |
||||
|
||||
err = fscrypt_require_key(dir); |
||||
if (err) |
||||
return err; |
||||
|
||||
if (!fscrypt_has_permitted_context(dir, inode)) |
||||
return -EPERM; |
||||
|
||||
return 0; |
||||
} |
||||
EXPORT_SYMBOL_GPL(__fscrypt_prepare_link); |
||||
|
||||
int __fscrypt_prepare_rename(struct inode *old_dir, struct dentry *old_dentry, |
||||
struct inode *new_dir, struct dentry *new_dentry, |
||||
unsigned int flags) |
||||
{ |
||||
int err; |
||||
|
||||
err = fscrypt_require_key(old_dir); |
||||
if (err) |
||||
return err; |
||||
|
||||
err = fscrypt_require_key(new_dir); |
||||
if (err) |
||||
return err; |
||||
|
||||
if (old_dir != new_dir) { |
||||
if (IS_ENCRYPTED(new_dir) && |
||||
!fscrypt_has_permitted_context(new_dir, |
||||
d_inode(old_dentry))) |
||||
return -EPERM; |
||||
|
||||
if ((flags & RENAME_EXCHANGE) && |
||||
IS_ENCRYPTED(old_dir) && |
||||
!fscrypt_has_permitted_context(old_dir, |
||||
d_inode(new_dentry))) |
||||
return -EPERM; |
||||
} |
||||
return 0; |
||||
} |
||||
EXPORT_SYMBOL_GPL(__fscrypt_prepare_rename); |
||||
|
||||
int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry) |
||||
{ |
||||
int err = fscrypt_get_encryption_info(dir); |
||||
|
||||
if (err) |
||||
return err; |
||||
|
||||
if (fscrypt_has_encryption_key(dir)) { |
||||
spin_lock(&dentry->d_lock); |
||||
dentry->d_flags |= DCACHE_ENCRYPTED_WITH_KEY; |
||||
spin_unlock(&dentry->d_lock); |
||||
} |
||||
|
||||
d_set_d_op(dentry, &fscrypt_d_ops); |
||||
return 0; |
||||
} |
||||
EXPORT_SYMBOL_GPL(__fscrypt_prepare_lookup); |
||||
@ -0,0 +1,294 @@ |
||||
/* SPDX-License-Identifier: GPL-2.0 */ |
||||
/*
|
||||
* fscrypt.h: declarations for per-file encryption |
||||
* |
||||
* Filesystems that implement per-file encryption include this header |
||||
* file with the __FS_HAS_ENCRYPTION set according to whether that filesystem |
||||
* is being built with encryption support or not. |
||||
* |
||||
* Copyright (C) 2015, Google, Inc. |
||||
* |
||||
* Written by Michael Halcrow, 2015. |
||||
* Modified by Jaegeuk Kim, 2015. |
||||
*/ |
||||
#ifndef _LINUX_FSCRYPT_H |
||||
#define _LINUX_FSCRYPT_H |
||||
|
||||
#include <linux/key.h> |
||||
#include <linux/fs.h> |
||||
#include <linux/mm.h> |
||||
#include <linux/bio.h> |
||||
#include <linux/dcache.h> |
||||
#include <crypto/skcipher.h> |
||||
#include <uapi/linux/fs.h> |
||||
|
||||
#define FS_CRYPTO_BLOCK_SIZE 16 |
||||
|
||||
struct fscrypt_info; |
||||
|
||||
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 */ |
||||
}; |
||||
|
||||
/**
|
||||
* 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; |
||||
|
||||
struct fscrypt_str { |
||||
unsigned char *name; |
||||
u32 len; |
||||
}; |
||||
|
||||
struct fscrypt_name { |
||||
const struct qstr *usr_fname; |
||||
struct fscrypt_str disk_name; |
||||
u32 hash; |
||||
u32 minor_hash; |
||||
struct fscrypt_str crypto_buf; |
||||
}; |
||||
|
||||
#define FSTR_INIT(n, l) { .name = n, .len = l } |
||||
#define FSTR_TO_QSTR(f) QSTR_INIT((f)->name, (f)->len) |
||||
#define fname_name(p) ((p)->disk_name.name) |
||||
#define fname_len(p) ((p)->disk_name.len) |
||||
|
||||
/*
|
||||
* fscrypt superblock flags |
||||
*/ |
||||
#define FS_CFLG_OWN_PAGES (1U << 1) |
||||
|
||||
/*
|
||||
* crypto opertions for filesystems |
||||
*/ |
||||
struct fscrypt_operations { |
||||
unsigned int flags; |
||||
const char *key_prefix; |
||||
int (*get_context)(struct inode *, void *, size_t); |
||||
int (*set_context)(struct inode *, const void *, size_t, void *); |
||||
bool (*dummy_context)(struct inode *); |
||||
bool (*empty_dir)(struct inode *); |
||||
unsigned (*max_namelen)(struct inode *); |
||||
}; |
||||
|
||||
/* Maximum value for the third parameter of fscrypt_operations.set_context(). */ |
||||
#define FSCRYPT_SET_CONTEXT_MAX_SIZE 28 |
||||
|
||||
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_enc_modes(u32 contents_mode, |
||||
u32 filenames_mode) |
||||
{ |
||||
if (contents_mode == FS_ENCRYPTION_MODE_AES_128_CBC && |
||||
filenames_mode == FS_ENCRYPTION_MODE_AES_128_CTS) |
||||
return true; |
||||
|
||||
if (contents_mode == FS_ENCRYPTION_MODE_AES_256_XTS && |
||||
filenames_mode == FS_ENCRYPTION_MODE_AES_256_CTS) |
||||
return true; |
||||
|
||||
return false; |
||||
} |
||||
|
||||
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; |
||||
} |
||||
|
||||
#if __FS_HAS_ENCRYPTION |
||||
|
||||
static inline struct page *fscrypt_control_page(struct page *page) |
||||
{ |
||||
return ((struct fscrypt_ctx *)page_private(page))->w.control_page; |
||||
} |
||||
|
||||
static inline bool fscrypt_has_encryption_key(const struct inode *inode) |
||||
{ |
||||
return (inode->i_crypt_info != NULL); |
||||
} |
||||
|
||||
#include <linux/fscrypt_supp.h> |
||||
|
||||
#else /* !__FS_HAS_ENCRYPTION */ |
||||
|
||||
static inline struct page *fscrypt_control_page(struct page *page) |
||||
{ |
||||
WARN_ON_ONCE(1); |
||||
return ERR_PTR(-EINVAL); |
||||
} |
||||
|
||||
static inline bool fscrypt_has_encryption_key(const struct inode *inode) |
||||
{ |
||||
return 0; |
||||
} |
||||
|
||||
#include <linux/fscrypt_notsupp.h> |
||||
#endif /* __FS_HAS_ENCRYPTION */ |
||||
|
||||
/**
|
||||
* fscrypt_require_key - require an inode's encryption key |
||||
* @inode: the inode we need the key for |
||||
* |
||||
* If the inode is encrypted, set up its encryption key if not already done. |
||||
* Then require that the key be present and return -ENOKEY otherwise. |
||||
* |
||||
* No locks are needed, and the key will live as long as the struct inode --- so |
||||
* it won't go away from under you. |
||||
* |
||||
* Return: 0 on success, -ENOKEY if the key is missing, or another -errno code |
||||
* if a problem occurred while setting up the encryption key. |
||||
*/ |
||||
static inline int fscrypt_require_key(struct inode *inode) |
||||
{ |
||||
if (IS_ENCRYPTED(inode)) { |
||||
int err = fscrypt_get_encryption_info(inode); |
||||
|
||||
if (err) |
||||
return err; |
||||
if (!fscrypt_has_encryption_key(inode)) |
||||
return -ENOKEY; |
||||
} |
||||
return 0; |
||||
} |
||||
|
||||
/**
|
||||
* fscrypt_prepare_link - prepare to link an inode into a possibly-encrypted directory |
||||
* @old_dentry: an existing dentry for the inode being linked |
||||
* @dir: the target directory |
||||
* @dentry: negative dentry for the target filename |
||||
* |
||||
* A new link can only be added to an encrypted directory if the directory's |
||||
* encryption key is available --- since otherwise we'd have no way to encrypt |
||||
* the filename. Therefore, we first set up the directory's encryption key (if |
||||
* not already done) and return an error if it's unavailable. |
||||
* |
||||
* We also verify that the link will not violate the constraint that all files |
||||
* in an encrypted directory tree use the same encryption policy. |
||||
* |
||||
* Return: 0 on success, -ENOKEY if the directory's encryption key is missing, |
||||
* -EPERM if the link would result in an inconsistent encryption policy, or |
||||
* another -errno code. |
||||
*/ |
||||
static inline int fscrypt_prepare_link(struct dentry *old_dentry, |
||||
struct inode *dir, |
||||
struct dentry *dentry) |
||||
{ |
||||
if (IS_ENCRYPTED(dir)) |
||||
return __fscrypt_prepare_link(d_inode(old_dentry), dir); |
||||
return 0; |
||||
} |
||||
|
||||
/**
|
||||
* fscrypt_prepare_rename - prepare for a rename between possibly-encrypted directories |
||||
* @old_dir: source directory |
||||
* @old_dentry: dentry for source file |
||||
* @new_dir: target directory |
||||
* @new_dentry: dentry for target location (may be negative unless exchanging) |
||||
* @flags: rename flags (we care at least about %RENAME_EXCHANGE) |
||||
* |
||||
* Prepare for ->rename() where the source and/or target directories may be |
||||
* encrypted. A new link can only be added to an encrypted directory if the |
||||
* directory's encryption key is available --- since otherwise we'd have no way |
||||
* to encrypt the filename. A rename to an existing name, on the other hand, |
||||
* *is* cryptographically possible without the key. However, we take the more |
||||
* conservative approach and just forbid all no-key renames. |
||||
* |
||||
* We also verify that the rename will not violate the constraint that all files |
||||
* in an encrypted directory tree use the same encryption policy. |
||||
* |
||||
* Return: 0 on success, -ENOKEY if an encryption key is missing, -EPERM if the |
||||
* rename would cause inconsistent encryption policies, or another -errno code. |
||||
*/ |
||||
static inline int fscrypt_prepare_rename(struct inode *old_dir, |
||||
struct dentry *old_dentry, |
||||
struct inode *new_dir, |
||||
struct dentry *new_dentry, |
||||
unsigned int flags) |
||||
{ |
||||
if (IS_ENCRYPTED(old_dir) || IS_ENCRYPTED(new_dir)) |
||||
return __fscrypt_prepare_rename(old_dir, old_dentry, |
||||
new_dir, new_dentry, flags); |
||||
return 0; |
||||
} |
||||
|
||||
/**
|
||||
* fscrypt_prepare_lookup - prepare to lookup a name in a possibly-encrypted directory |
||||
* @dir: directory being searched |
||||
* @dentry: filename being looked up |
||||
* @flags: lookup flags |
||||
* |
||||
* Prepare for ->lookup() in a directory which may be encrypted. Lookups can be |
||||
* done with or without the directory's encryption key; without the key, |
||||
* filenames are presented in encrypted form. Therefore, we'll try to set up |
||||
* the directory's encryption key, but even without it the lookup can continue. |
||||
* |
||||
* To allow invalidating stale dentries if the directory's encryption key is |
||||
* added later, we also install a custom ->d_revalidate() method and use the |
||||
* DCACHE_ENCRYPTED_WITH_KEY flag to indicate whether a given dentry is a |
||||
* plaintext name (flag set) or a ciphertext name (flag cleared). |
||||
* |
||||
* Return: 0 on success, -errno if a problem occurred while setting up the |
||||
* encryption key |
||||
*/ |
||||
static inline int fscrypt_prepare_lookup(struct inode *dir, |
||||
struct dentry *dentry, |
||||
unsigned int flags) |
||||
{ |
||||
if (IS_ENCRYPTED(dir)) |
||||
return __fscrypt_prepare_lookup(dir, dentry); |
||||
return 0; |
||||
} |
||||
|
||||
/**
|
||||
* fscrypt_prepare_setattr - prepare to change a possibly-encrypted inode's attributes |
||||
* @dentry: dentry through which the inode is being changed |
||||
* @attr: attributes to change |
||||
* |
||||
* Prepare for ->setattr() on a possibly-encrypted inode. On an encrypted file, |
||||
* most attribute changes are allowed even without the encryption key. However, |
||||
* without the encryption key we do have to forbid truncates. This is needed |
||||
* because the size being truncated to may not be a multiple of the filesystem |
||||
* block size, and in that case we'd have to decrypt the final block, zero the |
||||
* portion past i_size, and re-encrypt it. (We *could* allow truncating to a |
||||
* filesystem block boundary, but it's simpler to just forbid all truncates --- |
||||
* and we already forbid all other contents modifications without the key.) |
||||
* |
||||
* Return: 0 on success, -ENOKEY if the key is missing, or another -errno code |
||||
* if a problem occurred while setting up the encryption key. |
||||
*/ |
||||
static inline int fscrypt_prepare_setattr(struct dentry *dentry, |
||||
struct iattr *attr) |
||||
{ |
||||
if (attr->ia_valid & ATTR_SIZE) |
||||
return fscrypt_require_key(d_inode(dentry)); |
||||
return 0; |
||||
} |
||||
|
||||
#endif /* _LINUX_FSCRYPT_H */ |
||||
@ -1,142 +0,0 @@ |
||||
/* SPDX-License-Identifier: GPL-2.0 */ |
||||
/*
|
||||
* fscrypt_common.h: common declarations for per-file encryption |
||||
* |
||||
* Copyright (C) 2015, Google, Inc. |
||||
* |
||||
* Written by Michael Halcrow, 2015. |
||||
* Modified by Jaegeuk Kim, 2015. |
||||
*/ |
||||
|
||||
#ifndef _LINUX_FSCRYPT_COMMON_H |
||||
#define _LINUX_FSCRYPT_COMMON_H |
||||
|
||||
#include <linux/key.h> |
||||
#include <linux/fs.h> |
||||
#include <linux/mm.h> |
||||
#include <linux/bio.h> |
||||
#include <linux/dcache.h> |
||||
#include <crypto/skcipher.h> |
||||
#include <uapi/linux/fs.h> |
||||
|
||||
#define FS_CRYPTO_BLOCK_SIZE 16 |
||||
|
||||
struct fscrypt_info; |
||||
|
||||
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 */ |
||||
}; |
||||
|
||||
/**
|
||||
* 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; |
||||
|
||||
struct fscrypt_str { |
||||
unsigned char *name; |
||||
u32 len; |
||||
}; |
||||
|
||||
struct fscrypt_name { |
||||
const struct qstr *usr_fname; |
||||
struct fscrypt_str disk_name; |
||||
u32 hash; |
||||
u32 minor_hash; |
||||
struct fscrypt_str crypto_buf; |
||||
}; |
||||
|
||||
#define FSTR_INIT(n, l) { .name = n, .len = l } |
||||
#define FSTR_TO_QSTR(f) QSTR_INIT((f)->name, (f)->len) |
||||
#define fname_name(p) ((p)->disk_name.name) |
||||
#define fname_len(p) ((p)->disk_name.len) |
||||
|
||||
/*
|
||||
* fscrypt superblock flags |
||||
*/ |
||||
#define FS_CFLG_OWN_PAGES (1U << 1) |
||||
|
||||
/*
|
||||
* crypto opertions for filesystems |
||||
*/ |
||||
struct fscrypt_operations { |
||||
unsigned int flags; |
||||
const char *key_prefix; |
||||
int (*get_context)(struct inode *, void *, size_t); |
||||
int (*set_context)(struct inode *, const void *, size_t, void *); |
||||
bool (*dummy_context)(struct inode *); |
||||
bool (*is_encrypted)(struct inode *); |
||||
bool (*empty_dir)(struct inode *); |
||||
unsigned (*max_namelen)(struct inode *); |
||||
}; |
||||
|
||||
/* Maximum value for the third parameter of fscrypt_operations.set_context(). */ |
||||
#define FSCRYPT_SET_CONTEXT_MAX_SIZE 28 |
||||
|
||||
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_enc_modes(u32 contents_mode, |
||||
u32 filenames_mode) |
||||
{ |
||||
if (contents_mode == FS_ENCRYPTION_MODE_AES_128_CBC && |
||||
filenames_mode == FS_ENCRYPTION_MODE_AES_128_CTS) |
||||
return true; |
||||
|
||||
if (contents_mode == FS_ENCRYPTION_MODE_AES_256_XTS && |
||||
filenames_mode == FS_ENCRYPTION_MODE_AES_256_CTS) |
||||
return true; |
||||
|
||||
return false; |
||||
} |
||||
|
||||
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(const struct inode *inode) |
||||
{ |
||||
#if IS_ENABLED(CONFIG_FS_ENCRYPTION) |
||||
return (inode->i_crypt_info != NULL); |
||||
#else |
||||
return 0; |
||||
#endif |
||||
} |
||||
|
||||
#endif /* _LINUX_FSCRYPT_COMMON_H */ |
||||
Loading…
Reference in new issue