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-rw-r--r--include/linux/fscrypt_supp.h204
1 files changed, 0 insertions, 204 deletions
diff --git a/include/linux/fscrypt_supp.h b/include/linux/fscrypt_supp.h
deleted file mode 100644
index 6456c6b2005f..000000000000
--- a/include/linux/fscrypt_supp.h
+++ /dev/null
@@ -1,204 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * fscrypt_supp.h
- *
- * Do not include this file directly. Use fscrypt.h instead!
- */
-#ifndef _LINUX_FSCRYPT_H
-#error "Incorrect include of linux/fscrypt_supp.h!"
-#endif
-
-#ifndef _LINUX_FSCRYPT_SUPP_H
-#define _LINUX_FSCRYPT_SUPP_H
-
-#include <linux/mm.h>
-#include <linux/slab.h>
-
-/*
- * fscrypt superblock flags
- */
-#define FS_CFLG_OWN_PAGES (1U << 1)
-
-/*
- * crypto operations 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 int max_namelen;
-};
-
-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 */
-};
-
-static inline bool fscrypt_has_encryption_key(const struct inode *inode)
-{
- return (inode->i_crypt_info != NULL);
-}
-
-static inline bool fscrypt_dummy_context_enabled(struct inode *inode)
-{
- return inode->i_sb->s_cop->dummy_context &&
- inode->i_sb->s_cop->dummy_context(inode);
-}
-
-/* crypto.c */
-extern void fscrypt_enqueue_decrypt_work(struct work_struct *);
-extern struct fscrypt_ctx *fscrypt_get_ctx(const struct inode *, gfp_t);
-extern void fscrypt_release_ctx(struct fscrypt_ctx *);
-extern struct page *fscrypt_encrypt_page(const struct inode *, struct page *,
- unsigned int, unsigned int,
- u64, gfp_t);
-extern int fscrypt_decrypt_page(const struct inode *, struct page *, unsigned int,
- unsigned int, u64);
-
-static inline struct page *fscrypt_control_page(struct page *page)
-{
- return ((struct fscrypt_ctx *)page_private(page))->w.control_page;
-}
-
-extern void fscrypt_restore_control_page(struct page *);
-
-/* policy.c */
-extern int fscrypt_ioctl_set_policy(struct file *, const void __user *);
-extern int fscrypt_ioctl_get_policy(struct file *, void __user *);
-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 fscrypt_get_encryption_info(struct inode *);
-extern void fscrypt_put_encryption_info(struct inode *);
-
-/* fname.c */
-extern int fscrypt_setup_filename(struct inode *, const struct qstr *,
- int lookup, struct fscrypt_name *);
-
-static inline void fscrypt_free_filename(struct fscrypt_name *fname)
-{
- kfree(fname->crypto_buf.name);
-}
-
-extern int fscrypt_fname_alloc_buffer(const 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 *);
-
-#define FSCRYPT_FNAME_MAX_UNDIGESTED_SIZE 32
-
-/* Extracts the second-to-last ciphertext block; see explanation below */
-#define FSCRYPT_FNAME_DIGEST(name, len) \
- ((name) + round_down((len) - FS_CRYPTO_BLOCK_SIZE - 1, \
- FS_CRYPTO_BLOCK_SIZE))
-
-#define FSCRYPT_FNAME_DIGEST_SIZE FS_CRYPTO_BLOCK_SIZE
-
-/**
- * fscrypt_digested_name - alternate identifier for an on-disk filename
- *
- * When userspace lists an encrypted directory without access to the key,
- * filenames whose ciphertext is longer than FSCRYPT_FNAME_MAX_UNDIGESTED_SIZE
- * bytes are shown in this abbreviated form (base64-encoded) rather than as the
- * full ciphertext (base64-encoded). This is necessary to allow supporting
- * filenames up to NAME_MAX bytes, since base64 encoding expands the length.
- *
- * To make it possible for filesystems to still find the correct directory entry
- * despite not knowing the full on-disk name, we encode any filesystem-specific
- * 'hash' and/or 'minor_hash' which the filesystem may need for its lookups,
- * followed by the second-to-last ciphertext block of the filename. Due to the
- * use of the CBC-CTS encryption mode, the second-to-last ciphertext block
- * depends on the full plaintext. (Note that ciphertext stealing causes the
- * last two blocks to appear "flipped".) This makes accidental collisions very
- * unlikely: just a 1 in 2^128 chance for two filenames to collide even if they
- * share the same filesystem-specific hashes.
- *
- * However, this scheme isn't immune to intentional collisions, which can be
- * created by anyone able to create arbitrary plaintext filenames and view them
- * without the key. Making the "digest" be a real cryptographic hash like
- * SHA-256 over the full ciphertext would prevent this, although it would be
- * less efficient and harder to implement, especially since the filesystem would
- * need to calculate it for each directory entry examined during a search.
- */
-struct fscrypt_digested_name {
- u32 hash;
- u32 minor_hash;
- u8 digest[FSCRYPT_FNAME_DIGEST_SIZE];
-};
-
-/**
- * fscrypt_match_name() - test whether the given name matches a directory entry
- * @fname: the name being searched for
- * @de_name: the name from the directory entry
- * @de_name_len: the length of @de_name in bytes
- *
- * Normally @fname->disk_name will be set, and in that case we simply compare
- * that to the name stored in the directory entry. The only exception is that
- * if we don't have the key for an encrypted directory and a filename in it is
- * very long, then we won't have the full disk_name and we'll instead need to
- * match against the fscrypt_digested_name.
- *
- * Return: %true if the name matches, otherwise %false.
- */
-static inline bool fscrypt_match_name(const struct fscrypt_name *fname,
- const u8 *de_name, u32 de_name_len)
-{
- if (unlikely(!fname->disk_name.name)) {
- const struct fscrypt_digested_name *n =
- (const void *)fname->crypto_buf.name;
- if (WARN_ON_ONCE(fname->usr_fname->name[0] != '_'))
- return false;
- if (de_name_len <= FSCRYPT_FNAME_MAX_UNDIGESTED_SIZE)
- return false;
- return !memcmp(FSCRYPT_FNAME_DIGEST(de_name, de_name_len),
- n->digest, FSCRYPT_FNAME_DIGEST_SIZE);
- }
-
- if (de_name_len != fname->disk_name.len)
- return false;
- return !memcmp(de_name, fname->disk_name.name, fname->disk_name.len);
-}
-
-/* bio.c */
-extern void fscrypt_decrypt_bio(struct bio *);
-extern void fscrypt_enqueue_decrypt_bio(struct fscrypt_ctx *ctx,
- struct bio *bio);
-extern void fscrypt_pullback_bio_page(struct page **, bool);
-extern int fscrypt_zeroout_range(const struct inode *, pgoff_t, sector_t,
- unsigned int);
-
-/* hooks.c */
-extern int fscrypt_file_open(struct inode *inode, struct file *filp);
-extern int __fscrypt_prepare_link(struct inode *inode, struct inode *dir);
-extern int __fscrypt_prepare_rename(struct inode *old_dir,
- struct dentry *old_dentry,
- struct inode *new_dir,
- struct dentry *new_dentry,
- unsigned int flags);
-extern int __fscrypt_prepare_lookup(struct inode *dir, struct dentry *dentry);
-extern int __fscrypt_prepare_symlink(struct inode *dir, unsigned int len,
- unsigned int max_len,
- struct fscrypt_str *disk_link);
-extern int __fscrypt_encrypt_symlink(struct inode *inode, const char *target,
- unsigned int len,
- struct fscrypt_str *disk_link);
-extern const char *fscrypt_get_symlink(struct inode *inode, const void *caddr,
- unsigned int max_size,
- struct delayed_call *done);
-
-#endif /* _LINUX_FSCRYPT_SUPP_H */