From patchwork Wed Jan 20 18:28:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeffrey Layton X-Patchwork-Id: 12033313 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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 3AFCFC4332E for ; Wed, 20 Jan 2021 18:33:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1DF5C233FE for ; Wed, 20 Jan 2021 18:33:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391968AbhATSdv (ORCPT ); Wed, 20 Jan 2021 13:33:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:51570 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404539AbhATSam (ORCPT ); Wed, 20 Jan 2021 13:30:42 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 408D72343F; Wed, 20 Jan 2021 18:28:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1611167336; bh=Ryv6/5FWTfH2LZxfQaLIyG2gjaoenMsFpsFLKCN9i7I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ViukQ74nGa2saOe/ez5T9V1vPyc28OFCT/sjd+sDC4ib6dWaqL0y1tkTfzXU4vUwa Ks45kcXbr81+qVdUFAQ6vd7VbgGEIXo6w5ttIRQlnYSp+GPTEmMZWasmcueQZeiJAE 7VxokpPIaIOky5FwimoX9duwk3CHviRpjIJG5PzEsPY3IXxmEjq34oy0rAy+MSmvNX wc1eS7GZi8hqoEIrZH1Rm6DnttIGcT3qKIk+XiD3sTiXTIHUthaknxE918wThXH6EK iKd34m5Z/ZIpcVis5DmvmWhWD0HuPBT9QTwHv3jn/Ov82m/HcbDzRl/h382bHGLVvD 1ubOQfGypjWww== From: Jeff Layton To: ceph-devel@vger.kernel.org Cc: linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [RFC PATCH v4 11/17] ceph: decode alternate_name in lease info Date: Wed, 20 Jan 2021 13:28:41 -0500 Message-Id: <20210120182847.644850-12-jlayton@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210120182847.644850-1-jlayton@kernel.org> References: <20210120182847.644850-1-jlayton@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org Ceph is a bit different from local filesystems, in that we don't want to store filenames as raw binary data, since we may also be dealing with clients that don't support fscrypt. We could just base64-encode the encrypted filenames, but that could leave us with filenames longer than NAME_MAX. It turns out that the MDS doesn't care much about filename length, but the clients do. To manage this, we've added a new "alternate name" field that can be optionally added to any dentry that we'll use to store the binary crypttext of the filename if its base64-encoded value will be longer than NAME_MAX. When a dentry has one of these names attached, the MDS will send it along in the lease info, which we can then store for later usage. Signed-off-by: Jeff Layton --- fs/ceph/mds_client.c | 37 +++++++++++++++++++++++++++---------- fs/ceph/mds_client.h | 11 +++++++---- 2 files changed, 34 insertions(+), 14 deletions(-) diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index a8b67b988c51..bf6d1e3afe7e 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -256,27 +256,41 @@ static int parse_reply_info_dir(void **p, void *end, static int parse_reply_info_lease(void **p, void *end, struct ceph_mds_reply_lease **lease, - u64 features) + u64 features, u32 *altname_len, u8 **altname) { + u8 struct_v; + u32 struct_len; + if (features == (u64)-1) { - u8 struct_v, struct_compat; - u32 struct_len; + u8 struct_compat; + ceph_decode_8_safe(p, end, struct_v, bad); ceph_decode_8_safe(p, end, struct_compat, bad); + /* struct_v is expected to be >= 1. we only understand * encoding whose struct_compat == 1. */ if (!struct_v || struct_compat != 1) goto bad; + ceph_decode_32_safe(p, end, struct_len, bad); - ceph_decode_need(p, end, struct_len, bad); - end = *p + struct_len; + } else { + struct_len = sizeof(**lease); + *altname_len = 0; + *altname = NULL; } - ceph_decode_need(p, end, sizeof(**lease), bad); + ceph_decode_need(p, end, struct_len, bad); *lease = *p; *p += sizeof(**lease); - if (features == (u64)-1) - *p = end; + + if (features == (u64)-1) { + if (struct_v >= 2) { + ceph_decode_32_safe(p, end, *altname_len, bad); + ceph_decode_need(p, end, *altname_len, bad); + *altname = *p; + *p += *altname_len; + } + } return 0; bad: return -EIO; @@ -306,7 +320,8 @@ static int parse_reply_info_trace(void **p, void *end, info->dname = *p; *p += info->dname_len; - err = parse_reply_info_lease(p, end, &info->dlease, features); + err = parse_reply_info_lease(p, end, &info->dlease, features, + &info->altname_len, &info->altname); if (err < 0) goto out_bad; } @@ -373,9 +388,11 @@ static int parse_reply_info_readdir(void **p, void *end, dout("parsed dir dname '%.*s'\n", rde->name_len, rde->name); /* dentry lease */ - err = parse_reply_info_lease(p, end, &rde->lease, features); + err = parse_reply_info_lease(p, end, &rde->lease, features, + &rde->altname_len, &rde->altname); if (err) goto out_bad; + /* inode */ err = parse_reply_info_in(p, end, &rde->inode, features); if (err < 0) diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h index b888c602942c..5fb3ebd67489 100644 --- a/fs/ceph/mds_client.h +++ b/fs/ceph/mds_client.h @@ -29,8 +29,8 @@ enum ceph_feature_type { CEPHFS_FEATURE_MULTI_RECONNECT, CEPHFS_FEATURE_DELEG_INO, CEPHFS_FEATURE_METRIC_COLLECT, - - CEPHFS_FEATURE_MAX = CEPHFS_FEATURE_METRIC_COLLECT, + CEPHFS_FEATURE_ALTERNATE_NAME, + CEPHFS_FEATURE_MAX = CEPHFS_FEATURE_ALTERNATE_NAME, }; /* @@ -45,8 +45,7 @@ enum ceph_feature_type { CEPHFS_FEATURE_MULTI_RECONNECT, \ CEPHFS_FEATURE_DELEG_INO, \ CEPHFS_FEATURE_METRIC_COLLECT, \ - \ - CEPHFS_FEATURE_MAX, \ + CEPHFS_FEATURE_ALTERNATE_NAME, \ } #define CEPHFS_FEATURES_CLIENT_REQUIRED {} @@ -93,7 +92,9 @@ struct ceph_mds_reply_info_in { struct ceph_mds_reply_dir_entry { char *name; + u8 *altname; u32 name_len; + u32 altname_len; struct ceph_mds_reply_lease *lease; struct ceph_mds_reply_info_in inode; loff_t offset; @@ -112,7 +113,9 @@ struct ceph_mds_reply_info_parsed { struct ceph_mds_reply_info_in diri, targeti; struct ceph_mds_reply_dirfrag *dirfrag; char *dname; + u8 *altname; u32 dname_len; + u32 altname_len; struct ceph_mds_reply_lease *dlease; /* extra */