diff options
Diffstat (limited to 'include/linux/fsverity.h')
| -rw-r--r-- | include/linux/fsverity.h | 93 |
1 files changed, 77 insertions, 16 deletions
diff --git a/include/linux/fsverity.h b/include/linux/fsverity.h index 40f14e5fed9d..119a3266791f 100644 --- a/include/linux/fsverity.h +++ b/include/linux/fsverity.h @@ -12,6 +12,7 @@ #define _LINUX_FSVERITY_H #include <linux/fs.h> +#include <linux/mm.h> #include <crypto/hash_info.h> #include <crypto/sha2.h> #include <uapi/linux/fsverity.h> @@ -93,8 +94,7 @@ struct fsverity_operations { * isn't already cached. Implementations may ignore this * argument; it's only a performance optimization. * - * This can be called at any time on an open verity file, as well as - * between ->begin_enable_verity() and ->end_enable_verity(). It may be + * This can be called at any time on an open verity file. It may be * called by multiple processes concurrently, even with the same page. * * Note that this must retrieve a *page*, not necessarily a *block*. @@ -109,9 +109,9 @@ struct fsverity_operations { * Write a Merkle tree block to the given inode. * * @inode: the inode for which the Merkle tree is being built - * @buf: block to write - * @index: 0-based index of the block within the Merkle tree - * @log_blocksize: log base 2 of the Merkle tree block size + * @buf: the Merkle tree block to write + * @pos: the position of the block in the Merkle tree (in bytes) + * @size: the Merkle tree block size (in bytes) * * This is only called between ->begin_enable_verity() and * ->end_enable_verity(). @@ -119,7 +119,7 @@ struct fsverity_operations { * Return: 0 on success, -errno on failure */ int (*write_merkle_tree_block)(struct inode *inode, const void *buf, - u64 index, int log_blocksize); + u64 pos, unsigned int size); }; #ifdef CONFIG_FS_VERITY @@ -148,9 +148,21 @@ int fsverity_get_digest(struct inode *inode, /* open.c */ -int fsverity_file_open(struct inode *inode, struct file *filp); -int fsverity_prepare_setattr(struct dentry *dentry, struct iattr *attr); -void fsverity_cleanup_inode(struct inode *inode); +int __fsverity_file_open(struct inode *inode, struct file *filp); +int __fsverity_prepare_setattr(struct dentry *dentry, struct iattr *attr); +void __fsverity_cleanup_inode(struct inode *inode); + +/** + * fsverity_cleanup_inode() - free the inode's verity info, if present + * @inode: an inode being evicted + * + * Filesystems must call this on inode eviction to free ->i_verity_info. + */ +static inline void fsverity_cleanup_inode(struct inode *inode) +{ + if (inode->i_verity_info) + __fsverity_cleanup_inode(inode); +} /* read_metadata.c */ @@ -158,7 +170,7 @@ int fsverity_ioctl_read_metadata(struct file *filp, const void __user *uarg); /* verify.c */ -bool fsverity_verify_page(struct page *page); +bool fsverity_verify_blocks(struct folio *folio, size_t len, size_t offset); void fsverity_verify_bio(struct bio *bio); void fsverity_enqueue_verify_work(struct work_struct *work); @@ -193,15 +205,15 @@ static inline int fsverity_get_digest(struct inode *inode, /* open.c */ -static inline int fsverity_file_open(struct inode *inode, struct file *filp) +static inline int __fsverity_file_open(struct inode *inode, struct file *filp) { - return IS_VERITY(inode) ? -EOPNOTSUPP : 0; + return -EOPNOTSUPP; } -static inline int fsverity_prepare_setattr(struct dentry *dentry, - struct iattr *attr) +static inline int __fsverity_prepare_setattr(struct dentry *dentry, + struct iattr *attr) { - return IS_VERITY(d_inode(dentry)) ? -EOPNOTSUPP : 0; + return -EOPNOTSUPP; } static inline void fsverity_cleanup_inode(struct inode *inode) @@ -218,7 +230,8 @@ static inline int fsverity_ioctl_read_metadata(struct file *filp, /* verify.c */ -static inline bool fsverity_verify_page(struct page *page) +static inline bool fsverity_verify_blocks(struct folio *folio, size_t len, + size_t offset) { WARN_ON(1); return false; @@ -236,6 +249,16 @@ static inline void fsverity_enqueue_verify_work(struct work_struct *work) #endif /* !CONFIG_FS_VERITY */ +static inline bool fsverity_verify_folio(struct folio *folio) +{ + return fsverity_verify_blocks(folio, folio_size(folio), 0); +} + +static inline bool fsverity_verify_page(struct page *page) +{ + return fsverity_verify_blocks(page_folio(page), PAGE_SIZE, 0); +} + /** * fsverity_active() - do reads from the inode need to go through fs-verity? * @inode: inode to check @@ -254,4 +277,42 @@ static inline bool fsverity_active(const struct inode *inode) return fsverity_get_info(inode) != NULL; } +/** + * fsverity_file_open() - prepare to open a verity file + * @inode: the inode being opened + * @filp: the struct file being set up + * + * When opening a verity file, deny the open if it is for writing. Otherwise, + * set up the inode's ->i_verity_info if not already done. + * + * When combined with fscrypt, this must be called after fscrypt_file_open(). + * Otherwise, we won't have the key set up to decrypt the verity metadata. + * + * Return: 0 on success, -errno on failure + */ +static inline int fsverity_file_open(struct inode *inode, struct file *filp) +{ + if (IS_VERITY(inode)) + return __fsverity_file_open(inode, filp); + return 0; +} + +/** + * fsverity_prepare_setattr() - prepare to change a verity inode's attributes + * @dentry: dentry through which the inode is being changed + * @attr: attributes to change + * + * Verity files are immutable, so deny truncates. This isn't covered by the + * open-time check because sys_truncate() takes a path, not a file descriptor. + * + * Return: 0 on success, -errno on failure + */ +static inline int fsverity_prepare_setattr(struct dentry *dentry, + struct iattr *attr) +{ + if (IS_VERITY(d_inode(dentry))) + return __fsverity_prepare_setattr(dentry, attr); + return 0; +} + #endif /* _LINUX_FSVERITY_H */ |