From: Darrick J. Wong <djwong@xxxxxxxxxx>
Create a function that will return selected information about the
geometry of the merkle tree. Online fsck for XFS will need this piece
to perform basic checks of the merkle tree.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
fs/verity/open.c | 32 ++++++++++++++++++++++++++++++++
include/linux/fsverity.h | 10 ++++++++++
2 files changed, 42 insertions(+)
diff --git a/fs/verity/open.c b/fs/verity/open.c
index 4777130322866..aa71a4d3cbff1 100644
--- a/fs/verity/open.c
+++ b/fs/verity/open.c
@@ -427,6 +427,38 @@ void __fsverity_cleanup_inode(struct inode *inode)
}
EXPORT_SYMBOL_GPL(__fsverity_cleanup_inode);
+/**
+ * fsverity_merkle_tree_geometry() - return Merkle tree geometry
+ * @inode: the inode to query
+ * @block_size: will be set to the size of a merkle tree block, in bytes
+ * @tree_size: will be set to the size of the merkle tree, in bytes
+ *
+ * Callers are not required to have opened the file.
+ *
+ * Return: 0 for success, -ENODATA if verity is not enabled, or any of the
+ * error codes that can result from loading verity information while opening a
+ * file.
+ */
+int fsverity_merkle_tree_geometry(struct inode *inode, unsigned int *block_size,
+ u64 *tree_size)
+{
+ struct fsverity_info *vi;
+ int error;
+
+ if (!IS_VERITY(inode))
+ return -ENODATA;
+
+ error = ensure_verity_info(inode);
+ if (error)
+ return error;
+
+ vi = inode->i_verity_info;
+ *block_size = vi->tree_params.block_size;
+ *tree_size = vi->tree_params.tree_size;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(fsverity_merkle_tree_geometry);
+
void __init fsverity_init_info_cache(void)
{
fsverity_info_cachep = KMEM_CACHE_USERCOPY(
diff --git a/include/linux/fsverity.h b/include/linux/fsverity.h
index 7c51d7cf835ec..a3a5b68bed0d3 100644
--- a/include/linux/fsverity.h
+++ b/include/linux/fsverity.h
@@ -243,6 +243,9 @@ 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_merkle_tree_geometry(struct inode *inode, unsigned int *block_size,
+ u64 *tree_size);
+
/**
* fsverity_cleanup_inode() - free the inode's verity info, if present
* @inode: an inode being evicted
@@ -326,6 +329,13 @@ static inline void fsverity_cleanup_inode(struct inode *inode)
{
}
+static inline int fsverity_merkle_tree_geometry(struct inode *inode,
+ unsigned int *block_size,
+ u64 *tree_size)
+{
+ return -EOPNOTSUPP;
+}
+
/* read_metadata.c */
static inline int fsverity_ioctl_read_metadata(struct file *filp,
