From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F84EC433E0 for ; Thu, 28 Jan 2021 01:36:01 +0000 (UTC) Received: from lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9A95E64D99; Thu, 28 Jan 2021 01:36:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A95E64D99 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-f2fs-devel-bounces@lists.sourceforge.net Received: from [127.0.0.1] (helo=sfs-ml-1.v29.lw.sourceforge.com) by sfs-ml-1.v29.lw.sourceforge.com with esmtp (Exim 4.90_1) (envelope-from ) id 1l4wE3-0007uN-S0; Thu, 28 Jan 2021 01:35:59 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-1.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l4wE1-0007u4-Rn for linux-f2fs-devel@lists.sourceforge.net; Thu, 28 Jan 2021 01:35:57 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=In-Reply-To:Content-Type:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=nIK+EkISMgBW+3QAdlp2jc0EuZJDoGUFsqFb7iGmQso=; b=UC9PqSNAVtRjSN0NUztkZMpb8g 32JceEGjxHNR+oy89D77IqHfkQEhsPZHrW+nbATQ3nOA6w3nsoAT2J/udrKTGCTqZkD6Y1aDBLlg6 MZ81hMAbtTBUnB41CBF1A/NfDi9fsKAfKd4OoNSu8/kVFIsLi2Xwwaz2d+CKqHoGyDqg=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To :From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=nIK+EkISMgBW+3QAdlp2jc0EuZJDoGUFsqFb7iGmQso=; b=ehwmRZiUK55pphqHvwaJisZdrV HW4+LlqOCdIIgY/aMZy9eO9BwyUXIIhQrye2FFQjTS2raxHk9YU4ScuI5CE+PthZFOVG1jwoq6ycy wpjR630953noukIpK6rmq9i85b/cRt9zuSMK6erO8+4BVnHOwWw8OW0ImySjfLPT0m/I=; Received: from mail.kernel.org ([198.145.29.99]) by sfi-mx-3.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92.2) id 1l4wDn-00FY2U-Gt for linux-f2fs-devel@lists.sourceforge.net; Thu, 28 Jan 2021 01:35:57 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 16B9F64DBD; Thu, 28 Jan 2021 01:11:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1611796276; bh=/Oilbb/ZZgtI9SkGEjwZzZmBkyn7LM79p8zwItCMxtc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=K41HnkPDh/xwHbUR9OrfWQtouLDVZAsS0qFXYGJycfwFM1vxZ5fc+CAZxG1Bifigw 0aHGw7RWaecdeAhDIg8IGmPQL1fRYzhfrBDI52nI0W3LroqedZGNIkRomC7em1gYdz MtVwl1aDA+k+T58788eXVA3CINl75CKl3ZDkPhk071i23c0W/7ydsnWIrfoS45pAik uX33yfGFCI+dHcxAtFKBULxSK67iOtJlqAqX/9ce/JAdDgLcVi86ijrvKy9YqJyjl4 qD/G0oHfRCyeW8d32chpwoGmY5N6VFcWgXuliJQa2edUUVcsR6Zqui9FYYgt/thoOW Lw41gGul7ee4w== Date: Wed, 27 Jan 2021 17:11:14 -0800 From: Jaegeuk Kim To: Eric Biggers Message-ID: References: <20210115181819.34732-1-ebiggers@kernel.org> <20210115181819.34732-6-ebiggers@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210115181819.34732-6-ebiggers@kernel.org> X-Headers-End: 1l4wDn-00FY2U-Gt Subject: Re: [f2fs-dev] [PATCH 5/6] fs-verity: support reading descriptor with ioctl X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Theodore Ts'o , linux-api@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, Victor Hsieh Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On 01/15, Eric Biggers wrote: > From: Eric Biggers > > Add support for FS_VERITY_METADATA_TYPE_DESCRIPTOR to > FS_IOC_READ_VERITY_METADATA. This allows a userspace server program to > retrieve the fs-verity descriptor of a file for serving to a client > which implements fs-verity compatible verification. See the patch which > introduced FS_IOC_READ_VERITY_METADATA for more details. > > "fs-verity descriptor" here means only the part that userspace cares > about because it is hashed to produce the file digest. It doesn't > include the signature which ext4 and f2fs append to the > fsverity_descriptor struct when storing it on-disk, since that way of > storing the signature is an implementation detail. The next patch adds > a separate metadata_type value for retrieving the signature separately. > > This has been tested using a new xfstest which calls this ioctl via a > new subcommand for the 'fsverity' program from fsverity-utils. > > Signed-off-by: Eric Biggers Reviewed-by: Jaegeuk Kim > --- > Documentation/filesystems/fsverity.rst | 4 +++ > fs/verity/read_metadata.c | 40 ++++++++++++++++++++++++++ > include/uapi/linux/fsverity.h | 1 + > 3 files changed, 45 insertions(+) > > diff --git a/Documentation/filesystems/fsverity.rst b/Documentation/filesystems/fsverity.rst > index 50b47a6d9ea11..6dc5772037ef9 100644 > --- a/Documentation/filesystems/fsverity.rst > +++ b/Documentation/filesystems/fsverity.rst > @@ -235,6 +235,7 @@ need this ioctl. > This ioctl takes in a pointer to the following structure:: > > #define FS_VERITY_METADATA_TYPE_MERKLE_TREE 1 > + #define FS_VERITY_METADATA_TYPE_DESCRIPTOR 2 > > struct fsverity_read_metadata_arg { > __u64 metadata_type; > @@ -252,6 +253,9 @@ This ioctl takes in a pointer to the following structure:: > the same order that their hashes are themselves hashed. > See `Merkle tree`_ for more information. > > +- ``FS_VERITY_METADATA_TYPE_DESCRIPTOR`` reads the fs-verity > + descriptor. See `fs-verity descriptor`_. > + > The semantics are similar to those of ``pread()``. ``offset`` > specifies the offset in bytes into the metadata item to read from, and > ``length`` specifies the maximum number of bytes to read from the > diff --git a/fs/verity/read_metadata.c b/fs/verity/read_metadata.c > index 0f8ad2991cf90..2dea6dd3bb05a 100644 > --- a/fs/verity/read_metadata.c > +++ b/fs/verity/read_metadata.c > @@ -76,6 +76,44 @@ static int fsverity_read_merkle_tree(struct inode *inode, > } > return retval ? retval : err; > } > + > +/* Copy the requested portion of the buffer to userspace. */ > +static int fsverity_read_buffer(void __user *dst, u64 offset, int length, > + const void *src, size_t src_length) > +{ > + if (offset >= src_length) > + return 0; > + src += offset; > + src_length -= offset; > + > + length = min_t(size_t, length, src_length); > + > + if (copy_to_user(dst, src, length)) > + return -EFAULT; > + > + return length; > +} > + > +static int fsverity_read_descriptor(struct inode *inode, > + void __user *buf, u64 offset, int length) > +{ > + struct fsverity_descriptor *desc; > + size_t desc_size; > + int res; > + > + res = fsverity_get_descriptor(inode, &desc, &desc_size); > + if (res) > + return res; > + > + /* don't include the signature */ > + desc_size = offsetof(struct fsverity_descriptor, signature); > + desc->sig_size = 0; > + > + res = fsverity_read_buffer(buf, offset, length, desc, desc_size); > + > + kfree(desc); > + return res; > +} > /** > * fsverity_ioctl_read_metadata() - read verity metadata from a file > * @filp: file to read the metadata from > @@ -118,6 +156,8 @@ int fsverity_ioctl_read_metadata(struct file *filp, const void __user *uarg) > case FS_VERITY_METADATA_TYPE_MERKLE_TREE: > return fsverity_read_merkle_tree(inode, vi, buf, arg.offset, > length); > + case FS_VERITY_METADATA_TYPE_DESCRIPTOR: > + return fsverity_read_descriptor(inode, buf, arg.offset, length); > default: > return -EINVAL; > } > diff --git a/include/uapi/linux/fsverity.h b/include/uapi/linux/fsverity.h > index 94003b153cb3d..41abc283dbccb 100644 > --- a/include/uapi/linux/fsverity.h > +++ b/include/uapi/linux/fsverity.h > @@ -84,6 +84,7 @@ struct fsverity_formatted_digest { > }; > > #define FS_VERITY_METADATA_TYPE_MERKLE_TREE 1 > +#define FS_VERITY_METADATA_TYPE_DESCRIPTOR 2 > > struct fsverity_read_metadata_arg { > __u64 metadata_type; > -- > 2.30.0 _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel