From patchwork Tue Apr 5 19:19:53 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 12802444 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9832C4321E for ; Wed, 6 Apr 2022 05:19:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1386472AbiDFFRc (ORCPT ); Wed, 6 Apr 2022 01:17:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36428 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1573569AbiDETWw (ORCPT ); Tue, 5 Apr 2022 15:22:52 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8616C46652; Tue, 5 Apr 2022 12:20:53 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 22BA5617EE; Tue, 5 Apr 2022 19:20:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DFF06C385A3; Tue, 5 Apr 2022 19:20:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1649186452; bh=kyYkU/Dchft4ACwgY94oRFa28SIAQLGaoAiYc1wr4Js=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iAOjDvpPE74286q/P5TJcdZcpkEp7FNy6KNHZRseCCJLqb1zTmDAIV+SZQm+hBWi4 Vb68EptgER1RBKv1zpSJD5VAtA5IdIu+Qcv0APwLOyszhQa8/Dsqe7w2boNUKpeLod 7cct4kv6h4EeH0dIkAtquhK1V2JYekqb4FFFhApgr/ZbyazLIR2OI1x9mVT5xdRsgq XW1gFIf7PG6AZ2Oxeggv6B6LUtvlnE+SaqEXKekUjsYEpaYQqHW0YItW4gxwMz5eHp sCvWhm17YWahQP9feMct/iu50nDt46RQ7YmTjhslNesBLlccl9IJUEfw1HlzYIAFUN hsx7ahqBtkHBQ== From: Jeff Layton To: idryomov@gmail.com, xiubli@redhat.com Cc: ceph-devel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-fscrypt@vger.kernel.org, linux-kernel@vger.kernel.org, lhenriques@suse.de Subject: [PATCH v13 22/59] ceph: send altname in MClientRequest Date: Tue, 5 Apr 2022 15:19:53 -0400 Message-Id: <20220405192030.178326-23-jlayton@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405192030.178326-1-jlayton@kernel.org> References: <20220405192030.178326-1-jlayton@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org In the event that we have a filename longer than CEPH_NOHASH_NAME_MAX, we'll need to hash the tail of the filename. The client however will still need to know the full name of the file if it has a key. To support this, the MClientRequest field has grown a new alternate_name field that we populate with the full (binary) crypttext of the filename. This is then transmitted to the clients in readdir or traces as part of the dentry lease. Add support for populating this field when the filenames are very long. Signed-off-by: Jeff Layton --- fs/ceph/mds_client.c | 75 +++++++++++++++++++++++++++++++++++++++++--- fs/ceph/mds_client.h | 3 ++ 2 files changed, 73 insertions(+), 5 deletions(-) diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 13367a358a85..0be1668b2c32 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -972,6 +972,7 @@ void ceph_mdsc_release_request(struct kref *kref) if (req->r_pagelist) ceph_pagelist_release(req->r_pagelist); kfree(req->r_fscrypt_auth); + kfree(req->r_altname); put_request_session(req); ceph_unreserve_caps(req->r_mdsc, &req->r_caps_reservation); WARN_ON_ONCE(!list_empty(&req->r_wait)); @@ -2386,6 +2387,63 @@ static inline u64 __get_oldest_tid(struct ceph_mds_client *mdsc) return mdsc->oldest_tid; } +#if IS_ENABLED(CONFIG_FS_ENCRYPTION) +static u8 *get_fscrypt_altname(const struct ceph_mds_request *req, u32 *plen) +{ + struct inode *dir = req->r_parent; + struct dentry *dentry = req->r_dentry; + u8 *cryptbuf = NULL; + u32 len = 0; + int ret = 0; + + /* only encode if we have parent and dentry */ + if (!dir || !dentry) + goto success; + + /* No-op unless this is encrypted */ + if (!IS_ENCRYPTED(dir)) + goto success; + + ret = __fscrypt_prepare_readdir(dir); + if (ret) + return ERR_PTR(ret); + + /* No key? Just ignore it. */ + if (!fscrypt_has_encryption_key(dir)) + goto success; + + if (!fscrypt_fname_encrypted_size(dir, dentry->d_name.len, NAME_MAX, &len)) { + WARN_ON_ONCE(1); + return ERR_PTR(-ENAMETOOLONG); + } + + /* No need to append altname if name is short enough */ + if (len <= CEPH_NOHASH_NAME_MAX) { + len = 0; + goto success; + } + + cryptbuf = kmalloc(len, GFP_KERNEL); + if (!cryptbuf) + return ERR_PTR(-ENOMEM); + + ret = fscrypt_fname_encrypt(dir, &dentry->d_name, cryptbuf, len); + if (ret) { + kfree(cryptbuf); + return ERR_PTR(ret); + } +success: + *plen = len; + return cryptbuf; +} +#else +static u8 *get_fscrypt_altname(const struct ceph_mds_request *req, u32 *plen) +{ + *plen = 0; + return NULL; +} +#endif + /** * ceph_mdsc_build_path - build a path string to a given dentry * @dentry: dentry to which path should be built @@ -2606,14 +2664,15 @@ static void encode_mclientrequest_tail(void **p, const struct ceph_mds_request * ceph_encode_timespec64(&ts, &req->r_stamp); ceph_encode_copy(p, &ts, sizeof(ts)); - /* gid_list */ + /* v4: gid_list */ ceph_encode_32(p, req->r_cred->group_info->ngroups); for (i = 0; i < req->r_cred->group_info->ngroups; i++) ceph_encode_64(p, from_kgid(&init_user_ns, req->r_cred->group_info->gid[i])); - /* v5: altname (TODO: skip for now) */ - ceph_encode_32(p, 0); + /* v5: altname */ + ceph_encode_32(p, req->r_altname_len); + ceph_encode_copy(p, req->r_altname, req->r_altname_len); /* v6: fscrypt_auth and fscrypt_file */ if (req->r_fscrypt_auth) { @@ -2669,7 +2728,13 @@ static struct ceph_msg *create_request_message(struct ceph_mds_session *session, goto out_free1; } - /* head */ + req->r_altname = get_fscrypt_altname(req, &req->r_altname_len); + if (IS_ERR(req->r_altname)) { + msg = ERR_CAST(req->r_altname); + req->r_altname = NULL; + goto out_free2; + } + len = legacy ? sizeof(*head) : sizeof(struct ceph_mds_request_head); /* filepaths */ @@ -2695,7 +2760,7 @@ static struct ceph_msg *create_request_message(struct ceph_mds_session *session, len += sizeof(u32) + (sizeof(u64) * req->r_cred->group_info->ngroups); /* alternate name */ - len += sizeof(u32); // TODO + len += sizeof(u32) + req->r_altname_len; /* fscrypt_auth */ len += sizeof(u32); // fscrypt_auth diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h index 2cc75f9ae7c7..cd719691a86d 100644 --- a/fs/ceph/mds_client.h +++ b/fs/ceph/mds_client.h @@ -290,6 +290,9 @@ struct ceph_mds_request { struct ceph_fscrypt_auth *r_fscrypt_auth; + u8 *r_altname; /* fscrypt binary crypttext for long filenames */ + u32 r_altname_len; /* length of r_altname */ + int r_fmode; /* file mode, if expecting cap */ int r_request_release_offset; const struct cred *r_cred;