From patchwork Mon Sep 14 19:16:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeffrey Layton X-Patchwork-Id: 11774647 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B9FEC6CA for ; Mon, 14 Sep 2020 19:17:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0DF9208E4 for ; Mon, 14 Sep 2020 19:17:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600111057; bh=oKXMY3huJ4gH9ve2CTeuG+2SJx1r8vcdkKAnbDC++Mw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CSjXdWqeIWz3omniaJ7led/wMf2KLZK2eFGXW/7XEI9m8loMH7jquMkF92QIztnez dEyXbxiG2+AWU+FOSwb7PWksZET06clnHeXV5Bhjf94jUI5WE98ASROHYpxBNt+HwD 9UfZB8+IL9vm9iwMHDg9PLi7dmwLVdi1HPQfTpMU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726004AbgINTR3 (ORCPT ); Mon, 14 Sep 2020 15:17:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:38960 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725984AbgINTRN (ORCPT ); Mon, 14 Sep 2020 15:17:13 -0400 Received: from tleilax.com (68-20-15-154.lightspeed.rlghnc.sbcglobal.net [68.20.15.154]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B263C21BE5; Mon, 14 Sep 2020 19:17:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600111033; bh=oKXMY3huJ4gH9ve2CTeuG+2SJx1r8vcdkKAnbDC++Mw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pm/zGL7KXx+QZR4JPxbkkOgVJ9hpR5kYmu9R27peQQzPYlxy/HLskYeNVFwO4bDTD ANY5nJ1w+5+uAFFqizipW4UC31Z0bevrmaGBX8egjHUMN9afzQB++1InqVhHASfUNk tvpUsi7x4u9PYPVbWYYQN6K9NpACL34xpnl1qiZU= From: Jeff Layton To: ceph-devel@vger.kernel.org, linux-fscrypt@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Subject: [RFC PATCH v3 04/16] fscrypt: add fscrypt_context_for_new_inode Date: Mon, 14 Sep 2020 15:16:55 -0400 Message-Id: <20200914191707.380444-5-jlayton@kernel.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200914191707.380444-1-jlayton@kernel.org> References: <20200914191707.380444-1-jlayton@kernel.org> MIME-Version: 1.0 Sender: linux-fscrypt-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org CephFS will need to be able to generate a context for a new "prepared" inode. Add a new routine for getting the context out of an in-core inode. Signed-off-by: Jeff Layton --- fs/crypto/policy.c | 35 ++++++++++++++++++++++++++++------- include/linux/fscrypt.h | 1 + 2 files changed, 29 insertions(+), 7 deletions(-) diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c index 97cf07543651..0888f950367b 100644 --- a/fs/crypto/policy.c +++ b/fs/crypto/policy.c @@ -655,6 +655,31 @@ const union fscrypt_policy *fscrypt_policy_to_inherit(struct inode *dir) return fscrypt_get_dummy_policy(dir->i_sb); } +/** + * fscrypt_context_for_new_inode() - create an encryption context for a new inode + * @ctx: where context should be written + * @inode: inode from which to fetch policy and nonce + * + * Given an in-core "prepared" (via fscrypt_prepare_new_inode) inode, + * generate a new context and write it to ctx. ctx _must_ be at least + * FSCRYPT_SET_CONTEXT_MAX_SIZE bytes. + * + * Returns size of the resulting context or a negative error code. + */ +int fscrypt_context_for_new_inode(void *ctx, struct inode *inode) +{ + struct fscrypt_info *ci = inode->i_crypt_info; + + BUILD_BUG_ON(sizeof(union fscrypt_context) != FSCRYPT_SET_CONTEXT_MAX_SIZE); + + /* fscrypt_prepare_new_inode() should have set up the key already. */ + if (WARN_ON_ONCE(!ci)) + return -ENOKEY; + + return fscrypt_new_context(ctx, &ci->ci_policy, ci->ci_nonce); +} +EXPORT_SYMBOL_GPL(fscrypt_context_for_new_inode); + /** * fscrypt_set_context() - Set the fscrypt context of a new inode * @inode: a new inode @@ -671,12 +696,9 @@ int fscrypt_set_context(struct inode *inode, void *fs_data) union fscrypt_context ctx; int ctxsize; - /* fscrypt_prepare_new_inode() should have set up the key already. */ - if (WARN_ON_ONCE(!ci)) - return -ENOKEY; - - BUILD_BUG_ON(sizeof(ctx) != FSCRYPT_SET_CONTEXT_MAX_SIZE); - ctxsize = fscrypt_new_context(&ctx, &ci->ci_policy, ci->ci_nonce); + ctxsize = fscrypt_context_for_new_inode(&ctx, inode); + if (ctxsize < 0) + return ctxsize; /* * This may be the first time the inode number is available, so do any @@ -689,7 +711,6 @@ int fscrypt_set_context(struct inode *inode, void *fs_data) fscrypt_hash_inode_number(ci, mk); } - return inode->i_sb->s_cop->set_context(inode, &ctx, ctxsize, fs_data); } EXPORT_SYMBOL_GPL(fscrypt_set_context); diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h index b547e1aabb00..a57d2a9869eb 100644 --- a/include/linux/fscrypt.h +++ b/include/linux/fscrypt.h @@ -148,6 +148,7 @@ int fscrypt_ioctl_get_policy_ex(struct file *filp, void __user *arg); int fscrypt_ioctl_get_nonce(struct file *filp, void __user *arg); int fscrypt_has_permitted_context(struct inode *parent, struct inode *child); int fscrypt_set_context(struct inode *inode, void *fs_data); +int fscrypt_context_for_new_inode(void *ctx, struct inode *inode); struct fscrypt_dummy_policy { const union fscrypt_policy *policy;