linux/fs/verity/enable.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Ioctl to enable verity on a file
 *
 * Copyright 2019 Google LLC
 */

#include "fsverity_private.h"

#include <crypto/hash.h>
#include <linux/mount.h>
#include <linux/sched/signal.h>
#include <linux/uaccess.h>

struct block_buffer { … };

/* Hash a block, writing the result to the next level's pending block buffer. */
static int hash_one_block(struct inode *inode,
			  const struct merkle_tree_params *params,
			  struct block_buffer *cur)
{ … }

static int write_merkle_tree_block(struct inode *inode, const u8 *buf,
				   unsigned long index,
				   const struct merkle_tree_params *params)
{ … }

/*
 * Build the Merkle tree for the given file using the given parameters, and
 * return the root hash in @root_hash.
 *
 * The tree is written to a filesystem-specific location as determined by the
 * ->write_merkle_tree_block() method.  However, the blocks that comprise the
 * tree are the same for all filesystems.
 */
static int build_merkle_tree(struct file *filp,
			     const struct merkle_tree_params *params,
			     u8 *root_hash)
{ … }

static int enable_verity(struct file *filp,
			 const struct fsverity_enable_arg *arg)
{ … }

/**
 * fsverity_ioctl_enable() - enable verity on a file
 * @filp: file to enable verity on
 * @uarg: user pointer to fsverity_enable_arg
 *
 * Enable fs-verity on a file.  See the "FS_IOC_ENABLE_VERITY" section of
 * Documentation/filesystems/fsverity.rst for the documentation.
 *
 * Return: 0 on success, -errno on failure
 */
int fsverity_ioctl_enable(struct file *filp, const void __user *uarg)
{ … }
EXPORT_SYMBOL_GPL(…);