From patchwork Wed Apr 12 11:08:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Xiubo Li X-Patchwork-Id: 672670 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 864E1C77B6E for ; Wed, 12 Apr 2023 11:13:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229971AbjDLLNr (ORCPT ); Wed, 12 Apr 2023 07:13:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229810AbjDLLNp (ORCPT ); Wed, 12 Apr 2023 07:13:45 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 445596E9A for ; Wed, 12 Apr 2023 04:12:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681297915; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VahqIYWbeVWTl/tnPE8MOrQgib481Em0csjEISf1KFk=; b=W9nbsSKUQPbyi2XIczKC0/MIztV5CSQc7hf8Sm1feEMrpsBwCp3f+4CPPOHhm5wKLlsxbN F3nPigRd2Il5Pu75rolqQja22PhQ58xu3rX+FhbAlVYozxTTthchzcaSF4o1vyvlGdvY/v jub9RyRksy/nsPv1I1w89NHGqih0828= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-558-jIekjrFpNzGE_r-Qz2a93g-1; Wed, 12 Apr 2023 07:11:52 -0400 X-MC-Unique: jIekjrFpNzGE_r-Qz2a93g-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C41C7858F09; Wed, 12 Apr 2023 11:11:51 +0000 (UTC) Received: from li-a71a4dcc-35d1-11b2-a85c-951838863c8d.ibm.com.com (ovpn-12-131.pek2.redhat.com [10.72.12.131]) by smtp.corp.redhat.com (Postfix) with ESMTP id 231E4C15BB8; Wed, 12 Apr 2023 11:11:47 +0000 (UTC) From: xiubli@redhat.com To: idryomov@gmail.com, ceph-devel@vger.kernel.org Cc: jlayton@kernel.org, vshankar@redhat.com, mchangir@redhat.com, lhenriques@suse.de, Xiubo Li Subject: [PATCH v18 26/71] ceph: add helpers for converting names for userland presentation Date: Wed, 12 Apr 2023 19:08:45 +0800 Message-Id: <20230412110930.176835-27-xiubli@redhat.com> In-Reply-To: <20230412110930.176835-1-xiubli@redhat.com> References: <20230412110930.176835-1-xiubli@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org From: Jeff Layton Define a new ceph_fname struct that we can use to carry information about encrypted dentry names. Add helpers for working with these objects, including ceph_fname_to_usr which formats an encrypted filename for userland presentation. [ xiubli: s/FSCRYPT_BASE64URL_CHARS/CEPH_BASE64_CHARS/ reported by kernel test robot ] Tested-by: Luís Henriques Tested-by: Venky Shankar Reviewed-by: Luís Henriques Reviewed-by: Xiubo Li Signed-off-by: Jeff Layton --- fs/ceph/crypto.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++ fs/ceph/crypto.h | 41 ++++++++++++++++++++++++++ 2 files changed, 117 insertions(+) diff --git a/fs/ceph/crypto.c b/fs/ceph/crypto.c index e54ea4c3e478..03f4b9e73884 100644 --- a/fs/ceph/crypto.c +++ b/fs/ceph/crypto.c @@ -234,3 +234,79 @@ int ceph_encode_encrypted_fname(const struct inode *parent, struct dentry *dentr dout("base64-encoded ciphertext name = %.*s\n", elen, buf); return elen; } + +/** + * ceph_fname_to_usr - convert a filename for userland presentation + * @fname: ceph_fname to be converted + * @tname: temporary name buffer to use for conversion (may be NULL) + * @oname: where converted name should be placed + * @is_nokey: set to true if key wasn't available during conversion (may be NULL) + * + * Given a filename (usually from the MDS), format it for presentation to + * userland. If @parent is not encrypted, just pass it back as-is. + * + * Otherwise, base64 decode the string, and then ask fscrypt to format it + * for userland presentation. + * + * Returns 0 on success or negative error code on error. + */ +int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname, + struct fscrypt_str *oname, bool *is_nokey) +{ + int ret; + struct fscrypt_str _tname = FSTR_INIT(NULL, 0); + struct fscrypt_str iname; + + if (!IS_ENCRYPTED(fname->dir)) { + oname->name = fname->name; + oname->len = fname->name_len; + return 0; + } + + /* Sanity check that the resulting name will fit in the buffer */ + if (fname->name_len > CEPH_BASE64_CHARS(NAME_MAX)) + return -EIO; + + ret = __fscrypt_prepare_readdir(fname->dir); + if (ret) + return ret; + + /* + * Use the raw dentry name as sent by the MDS instead of + * generating a nokey name via fscrypt. + */ + if (!fscrypt_has_encryption_key(fname->dir)) { + memcpy(oname->name, fname->name, fname->name_len); + oname->len = fname->name_len; + if (is_nokey) + *is_nokey = true; + return 0; + } + + if (fname->ctext_len == 0) { + int declen; + + if (!tname) { + ret = fscrypt_fname_alloc_buffer(NAME_MAX, &_tname); + if (ret) + return ret; + tname = &_tname; + } + + declen = fscrypt_base64url_decode(fname->name, fname->name_len, tname->name); + if (declen <= 0) { + ret = -EIO; + goto out; + } + iname.name = tname->name; + iname.len = declen; + } else { + iname.name = fname->ctext; + iname.len = fname->ctext_len; + } + + ret = fscrypt_fname_disk_to_usr(fname->dir, 0, 0, &iname, oname); +out: + fscrypt_fname_free_buffer(&_tname); + return ret; +} diff --git a/fs/ceph/crypto.h b/fs/ceph/crypto.h index 8abf10604722..f231d6e3ba0f 100644 --- a/fs/ceph/crypto.h +++ b/fs/ceph/crypto.h @@ -13,6 +13,14 @@ struct ceph_fs_client; struct ceph_acl_sec_ctx; struct ceph_mds_request; +struct ceph_fname { + struct inode *dir; + char *name; // b64 encoded, possibly hashed + unsigned char *ctext; // binary crypttext (if any) + u32 name_len; // length of name buffer + u32 ctext_len; // length of crypttext +}; + struct ceph_fscrypt_auth { __le32 cfa_version; __le32 cfa_blob_len; @@ -69,6 +77,22 @@ int ceph_fscrypt_prepare_context(struct inode *dir, struct inode *inode, void ceph_fscrypt_as_ctx_to_req(struct ceph_mds_request *req, struct ceph_acl_sec_ctx *as); int ceph_encode_encrypted_fname(const struct inode *parent, struct dentry *dentry, char *buf); +static inline int ceph_fname_alloc_buffer(struct inode *parent, struct fscrypt_str *fname) +{ + if (!IS_ENCRYPTED(parent)) + return 0; + return fscrypt_fname_alloc_buffer(NAME_MAX, fname); +} + +static inline void ceph_fname_free_buffer(struct inode *parent, struct fscrypt_str *fname) +{ + if (IS_ENCRYPTED(parent)) + fscrypt_fname_free_buffer(fname); +} + +int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname, + struct fscrypt_str *oname, bool *is_nokey); + #else /* CONFIG_FS_ENCRYPTION */ static inline void ceph_fscrypt_set_ops(struct super_block *sb) @@ -97,6 +121,23 @@ static inline int ceph_encode_encrypted_fname(const struct inode *parent, { return -EOPNOTSUPP; } + +static inline int ceph_fname_alloc_buffer(struct inode *parent, struct fscrypt_str *fname) +{ + return 0; +} + +static inline void ceph_fname_free_buffer(struct inode *parent, struct fscrypt_str *fname) +{ +} + +static inline int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname, + struct fscrypt_str *oname, bool *is_nokey) +{ + oname->name = fname->name; + oname->len = fname->name_len; + return 0; +} #endif /* CONFIG_FS_ENCRYPTION */ #endif