On Thu, Dec 02, 2021 at 04:55:03PM -0500, Mimi Zohar wrote:
> +
> +/**
> + * fsverity_collect_digest() - get a verity file's digest
> + * @inode: inode to get digest of
> + * @digest: (out) pointer to the digest
> + * @alg: (out) pointer to the hash algorithm enumeration
> + *
> + * Return the file hash algorithm and digest of an fsverity protected file.
> + *
> + * Return: 0 on success, -errno on failure
> + */
> +int fsverity_collect_digest(struct inode *inode,
> + u8 digest[FS_VERITY_MAX_DIGEST_SIZE],
> + enum hash_algo *alg)
I'd still prefer that this be named fsverity_get_digest(), but this is fine too.
> +{
> + const struct fsverity_info *vi;
> + const struct fsverity_hash_alg *hash_alg;
> + int i;
> +
> + vi = fsverity_get_info(inode);
> + if (!vi)
> + return -ENODATA; /* not a verity file */
> +
> + hash_alg = vi->tree_params.hash_alg;
> + memset(digest, 0, FS_VERITY_MAX_DIGEST_SIZE);
> + *alg = HASH_ALGO__LAST;
> +
> + /* convert hash algorithm to hash_algo_name */
> + for (i = 0; i < HASH_ALGO__LAST; i++) {
> + pr_debug("name %s hash_algo_name[%d] %s\n",
> + hash_alg->name, i, hash_algo_name[i]);
> +
> + if (!strcmp(hash_alg->name, hash_algo_name[i])) {
> + *alg = i;
> + break;
> + }
> + }
How about using match_string() here?
> + pr_debug("file digest:%s %*phN\n", hash_algo_name[*alg],
> + hash_digest_size[*alg], digest);
Other log messages in fs/verity/ use the format alg:hash. How about using
"file_digest %s:%*phN\n" as the format string here?
- Eric
