forked from Minki/linux
6377a38bd3
Fix all kerneldoc warnings in fs/verity/ and include/linux/fsverity.h. Most of these were due to missing documentation for function parameters. Detected with: scripts/kernel-doc -v -none fs/verity/*.{c,h} include/linux/fsverity.h This cleanup makes it possible to check new patches for kerneldoc warnings without having to filter out all the existing ones. Link: https://lore.kernel.org/r/20200511192118.71427-2-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
60 lines
1.7 KiB
C
60 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* fs/verity/measure.c: ioctl to get a verity file's measurement
|
|
*
|
|
* Copyright 2019 Google LLC
|
|
*/
|
|
|
|
#include "fsverity_private.h"
|
|
|
|
#include <linux/uaccess.h>
|
|
|
|
/**
|
|
* fsverity_ioctl_measure() - get a verity file's measurement
|
|
* @filp: file to get measurement of
|
|
* @_uarg: user pointer to fsverity_digest
|
|
*
|
|
* Retrieve the file measurement that the kernel is enforcing for reads from a
|
|
* verity file. See the "FS_IOC_MEASURE_VERITY" section of
|
|
* Documentation/filesystems/fsverity.rst for the documentation.
|
|
*
|
|
* Return: 0 on success, -errno on failure
|
|
*/
|
|
int fsverity_ioctl_measure(struct file *filp, void __user *_uarg)
|
|
{
|
|
const struct inode *inode = file_inode(filp);
|
|
struct fsverity_digest __user *uarg = _uarg;
|
|
const struct fsverity_info *vi;
|
|
const struct fsverity_hash_alg *hash_alg;
|
|
struct fsverity_digest arg;
|
|
|
|
vi = fsverity_get_info(inode);
|
|
if (!vi)
|
|
return -ENODATA; /* not a verity file */
|
|
hash_alg = vi->tree_params.hash_alg;
|
|
|
|
/*
|
|
* The user specifies the digest_size their buffer has space for; we can
|
|
* return the digest if it fits in the available space. We write back
|
|
* the actual size, which may be shorter than the user-specified size.
|
|
*/
|
|
|
|
if (get_user(arg.digest_size, &uarg->digest_size))
|
|
return -EFAULT;
|
|
if (arg.digest_size < hash_alg->digest_size)
|
|
return -EOVERFLOW;
|
|
|
|
memset(&arg, 0, sizeof(arg));
|
|
arg.digest_algorithm = hash_alg - fsverity_hash_algs;
|
|
arg.digest_size = hash_alg->digest_size;
|
|
|
|
if (copy_to_user(uarg, &arg, sizeof(arg)))
|
|
return -EFAULT;
|
|
|
|
if (copy_to_user(uarg->digest, vi->measurement, hash_alg->digest_size))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fsverity_ioctl_measure);
|