1 files changed, 52 insertions, 2 deletions

diff --git a/fs/verity/fsverity_private.h b/fs/verity/fsverity_private.h
index 9697aaebb5dc..c79746ff335e 100644
--- a/fs/verity/fsverity_private.h
+++ b/fs/verity/fsverity_private.h
@@ -15,8 +15,7 @@
 #define pr_fmt(fmt) "fs-verity: " fmt
 
 #include <crypto/sha.h>
-#include <linux/fs.h>
-#include <uapi/linux/fsverity.h>
+#include <linux/fsverity.h>
 
 struct ahash_request;
 
@@ -59,6 +58,40 @@ struct merkle_tree_params {
 	u64 level_start[FS_VERITY_MAX_LEVELS];
 };
 
+/**
+ * fsverity_info - cached verity metadata for an inode
+ *
+ * When a verity file is first opened, an instance of this struct is allocated
+ * and stored in ->i_verity_info; it remains until the inode is evicted.  It
+ * caches information about the Merkle tree that's needed to efficiently verify
+ * data read from the file.  It also caches the file measurement.  The Merkle
+ * tree pages themselves are not cached here, but the filesystem may cache them.
+ */
+struct fsverity_info {
+	struct merkle_tree_params tree_params;
+	u8 root_hash[FS_VERITY_MAX_DIGEST_SIZE];
+	u8 measurement[FS_VERITY_MAX_DIGEST_SIZE];
+	const struct inode *inode;
+};
+
+/*
+ * Merkle tree properties.  The file measurement is the hash of this structure.
+ */
+struct fsverity_descriptor {
+	__u8 version;		/* must be 1 */
+	__u8 hash_algorithm;	/* Merkle tree hash algorithm */
+	__u8 log_blocksize;	/* log2 of size of data and tree blocks */
+	__u8 salt_size;		/* size of salt in bytes; 0 if none */
+	__le32 sig_size;	/* reserved, must be 0 */
+	__le64 data_size;	/* size of file the Merkle tree is built over */
+	__u8 root_hash[64];	/* Merkle tree root hash */
+	__u8 salt[32];		/* salt prepended to each hashed block */
+	__u8 __reserved[144];	/* must be 0's */
+};
+
+/* Arbitrary limit to bound the kmalloc() size.  Can be changed. */
+#define FS_VERITY_MAX_DESCRIPTOR_SIZE	16384
+
 /* hash_algs.c */
 
 extern struct fsverity_hash_alg fsverity_hash_algs[];
@@ -85,4 +118,21 @@ fsverity_msg(const struct inode *inode, const char *level,
 #define fsverity_err(inode, fmt, ...)		\
 	fsverity_msg((inode), KERN_ERR, fmt, ##__VA_ARGS__)
 
+/* open.c */
+
+int fsverity_init_merkle_tree_params(struct merkle_tree_params *params,
+				     const struct inode *inode,
+				     unsigned int hash_algorithm,
+				     unsigned int log_blocksize,
+				     const u8 *salt, size_t salt_size);
+
+struct fsverity_info *fsverity_create_info(const struct inode *inode,
+					   const void *desc, size_t desc_size);
+
+void fsverity_set_info(struct inode *inode, struct fsverity_info *vi);
+
+void fsverity_free_info(struct fsverity_info *vi);
+
+int __init fsverity_init_info_cache(void);
+
 #endif /* _FSVERITY_PRIVATE_H */