From patchwork Tue Nov 17 04:03:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Rosenberg X-Patchwork-Id: 11911565 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=-20.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 732A3C63798 for ; Tue, 17 Nov 2020 04:03:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 28AB42468E for ; Tue, 17 Nov 2020 04:03:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="shg3+cQ9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726338AbgKQEDX (ORCPT ); Mon, 16 Nov 2020 23:03:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58274 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727227AbgKQEDX (ORCPT ); Mon, 16 Nov 2020 23:03:23 -0500 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C3B7C061A04 for ; Mon, 16 Nov 2020 20:03:21 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id z29so23417883ybi.23 for ; Mon, 16 Nov 2020 20:03:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=26rm8pP8X1eqyqMFHjed3HgpBJsgTLVuVg1p5M5T4ac=; b=shg3+cQ9HKM0nPNtrMQTh+D5eQYXxiRjQHiCYna15DnDwGSI4q6hNF86FmwmCYrJ09 0uszwptNamjvsfa2d+Ebp170YA7jdMrfds4LdsowSETcYPuptonfbiP7v8hpd4Y0MZkg TcH5aai3GlIlPjDRJOutLlBhbMbEKGMg5F5w3kD5/X0fqC2FyU3uSCyFeDu5RIXt/ixa 9s2Vzm7JxAfAo2lWEtY1zChL12tD9p7+0mwGYHx+TBdw2Ath0P70x0MCBOufxM8RBgRH D/gZzY+rDOJ3wmUNZ5lYBs7E1V5A8uxoYtCXmruoFljhdbJ8IaBIehg5VrO1VZ4lsbQk 6BPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=26rm8pP8X1eqyqMFHjed3HgpBJsgTLVuVg1p5M5T4ac=; b=d1velVf22ZB2/OqZfmDmL7OwbgePRwQ/COwBTVclNB0FluVMUxWVImx650zXDmUcYt nTAnqvTgAvUUrachMMH897UsupinH+/x/JulQ9NqZGrPLYyjtWB1xZMIOfBT+9T9KyJD Ye60zrB2Jjufh1FLZm3muwZ+OBYCs56GCUE0lrr8o2Kv9VD+l/+fWBFjMz3yiiKHw69J 2NSabOIUizBtffqfLYO6I4+Hyq4KsBx9/irNYPwigCO4JzQqRAfio1Z5x/rzA+8Ixmqn ntUbDOJsFR/TozkzQUhhtR4JnGgO5tSHXTbcSmYiouqZRaytHYBV3or+iXgrNHUxkCnO tGsA== X-Gm-Message-State: AOAM533bcFoT04+Gi7tVJL7D3yT6ki5Iz4FGiDVpLHX5rdQTXbu1rHey BQNmn2PVu5JiGUq2roIWVsLX5kcDgP4= X-Google-Smtp-Source: ABdhPJzKALm1EBPTQ18K+cplc9Rj54/XCyTrRJBcCgve7DfHa3FcRADsKoXoWVc+0ELNdGgH6frN1aEubL8= Sender: "drosen via sendgmr" X-Received: from drosen.c.googlers.com ([fda3:e722:ac3:10:24:72f4:c0a8:4e6f]) (user=drosen job=sendgmr) by 2002:a25:88a:: with SMTP id 132mr26330262ybi.215.1605585800711; Mon, 16 Nov 2020 20:03:20 -0800 (PST) Date: Tue, 17 Nov 2020 04:03:13 +0000 In-Reply-To: <20201117040315.28548-1-drosen@google.com> Message-Id: <20201117040315.28548-2-drosen@google.com> Mime-Version: 1.0 References: <20201117040315.28548-1-drosen@google.com> X-Mailer: git-send-email 2.29.2.299.gdc1121823c-goog Subject: [PATCH v2 1/3] libfs: Add generic function for setting dentry_ops From: Daniel Rosenberg To: "Theodore Y . Ts'o" , Jaegeuk Kim , Eric Biggers , Andreas Dilger , Chao Yu , Alexander Viro , Richard Weinberger , linux-fscrypt@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mtd@lists.infradead.org, Gabriel Krisman Bertazi , kernel-team@android.com, Daniel Rosenberg Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org This adds a function to set dentry operations at lookup time that will work for both encrypted filenames and casefolded filenames. A filesystem that supports both features simultaneously can use this function during lookup preparations to set up its dentry operations once fscrypt no longer does that itself. Currently the casefolding dentry operation are always set if the filesystem defines an encoding because the features is toggleable on empty directories. Since we don't know what set of functions we'll eventually need, and cannot change them later, we add just add them. Signed-off-by: Daniel Rosenberg Reviewed-by: Theodore Ts'o --- fs/libfs.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 1 + 2 files changed, 61 insertions(+) diff --git a/fs/libfs.c b/fs/libfs.c index fc34361c1489..dd8504f3ff5d 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1449,4 +1449,64 @@ int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str) return 0; } EXPORT_SYMBOL(generic_ci_d_hash); + +static const struct dentry_operations generic_ci_dentry_ops = { + .d_hash = generic_ci_d_hash, + .d_compare = generic_ci_d_compare, +}; #endif + +#ifdef CONFIG_FS_ENCRYPTION +static const struct dentry_operations generic_encrypted_dentry_ops = { + .d_revalidate = fscrypt_d_revalidate, +}; +#endif + +#if IS_ENABLED(CONFIG_UNICODE) && IS_ENABLED(CONFIG_FS_ENCRYPTION) +static const struct dentry_operations generic_encrypted_ci_dentry_ops = { + .d_hash = generic_ci_d_hash, + .d_compare = generic_ci_d_compare, + .d_revalidate = fscrypt_d_revalidate, +}; +#endif + +/** + * generic_set_encrypted_ci_d_ops - helper for setting d_ops for given dentry + * @dentry: dentry to set ops on + * + * This function sets the dentry ops for the given dentry to handle both + * casefolded and encrypted dentry names. + * + * Encryption requires d_revalidate to remove nokey names once the key is present. + * Casefolding is toggleable on an empty directory. Since we can't change the + * operations later on, we just add the casefolding ops if the filesystem defines an + * encoding. + */ +void generic_set_encrypted_ci_d_ops(struct dentry *dentry) +{ +#ifdef CONFIG_FS_ENCRYPTION + bool needs_encrypt_ops = dentry->d_flags & DCACHE_NOKEY_NAME; +#endif +#ifdef CONFIG_UNICODE + bool needs_ci_ops = dentry->d_sb->s_encoding; +#endif +#if defined(CONFIG_FS_ENCRYPTION) && defined(CONFIG_UNICODE) + if (needs_encrypt_ops && needs_ci_ops) { + d_set_d_op(dentry, &generic_encrypted_ci_dentry_ops); + return; + } +#endif +#ifdef CONFIG_FS_ENCRYPTION + if (needs_encrypt_ops) { + d_set_d_op(dentry, &generic_encrypted_dentry_ops); + return; + } +#endif +#ifdef CONFIG_UNICODE + if (needs_ci_ops) { + d_set_d_op(dentry, &generic_ci_dentry_ops); + return; + } +#endif +} +EXPORT_SYMBOL(generic_set_encrypted_ci_d_ops); diff --git a/include/linux/fs.h b/include/linux/fs.h index 8667d0cdc71e..11345e66353b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3202,6 +3202,7 @@ extern int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str); extern int generic_ci_d_compare(const struct dentry *dentry, unsigned int len, const char *str, const struct qstr *name); #endif +extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry); #ifdef CONFIG_MIGRATION extern int buffer_migrate_page(struct address_space *,