From mboxrd@z Thu Jan 1 00:00:00 1970 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 753DBC433EF for ; Thu, 19 May 2022 21:24:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245170AbiESVYS (ORCPT ); Thu, 19 May 2022 17:24:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56828 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229873AbiESVYR (ORCPT ); Thu, 19 May 2022 17:24:17 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [46.235.227.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8F6FED787 for ; Thu, 19 May 2022 14:24:16 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id 9860B1F45F78 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1652995455; bh=Yy1A6Vts7piejGKGGyulGEO3LNJA5px4YK35G29ueMA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZrHMsEOJmFvhEzs15aYh1tXDMkSgUiYF9tw3YjXTGH7RpE2sA8jmIevP7hjhGh9MK 7jbv6DEEGeQc9c2Zl5WJzWWwE7Rcvc8e5UlpviS3fmLEl6SQsZVQiSZcsNkYcvTrkH A1En0Uum1NcKRdibeG19DkaTTl6mnyDSQ8/o3XwE0NvuWHr60WFrk27vQ/kPVBff7I o3lGTbh3dErMDeHWD/vSIsuDgI5+W6hLDWZzvBMuub4sZgKON3KxjL9YeEU87+HDqX Zb3ASp2SZ6TXA2Reh3cqla1Kyac04aM52kdzS/2Vfmxog3oBN2K/RsJhluBvLL9Pli JNIKxwDNYAs0Q== From: Gabriel Krisman Bertazi To: tytso@mit.edu, adilger.kernel@dilger.ca, jaegeuk@kernel.org, ebiggers@kernel.org Cc: linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Gabriel Krisman Bertazi , kernel@collabora.com, Eric Biggers Subject: [PATCH v8 3/8] libfs: Introduce case-insensitive string comparison helper Date: Thu, 19 May 2022 17:23:54 -0400 Message-Id: <20220519212359.19442-4-krisman@collabora.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220519212359.19442-1-krisman@collabora.com> References: <20220519212359.19442-1-krisman@collabora.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org generic_ci_match can be used by case-insensitive filesystems to compare strings under lookup with dirents in a case-insensitive way. This function is currently reimplemented by each filesystem supporting casefolding, so this reduces code duplication in filesystem-specific code. Reviewed-by: Eric Biggers Signed-off-by: Gabriel Krisman Bertazi --- Changes since v5: (eric) - Rename variable err -> res - Retype de_name_len from size_t to u32 - Bring WARN_ON_ONCE(!fscrypt_has_encryption_key) from f2fs implementation --- fs/libfs.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 4 +++ 2 files changed, 72 insertions(+) diff --git a/fs/libfs.c b/fs/libfs.c index 974125270a42..f1d88cd903f8 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1465,6 +1465,74 @@ static const struct dentry_operations generic_ci_dentry_ops = { .d_hash = generic_ci_d_hash, .d_compare = generic_ci_d_compare, }; + +/** + * generic_ci_match() - Match a name (case-insensitively) with a dirent. + * @parent: Inode of the parent of the dirent under comparison + * @name: name under lookup. + * @folded_name: Optional pre-folded name under lookup + * @de_name: Dirent name. + * @de_name_len: dirent name length. + * + * + * Test whether a case-insensitive directory entry matches the filename + * being searched. If @folded_name is provided, it is used instead of + * recalculating the casefold of @name. + * + * Return: > 0 if the directory entry matches, 0 if it doesn't match, or + * < 0 on error. + */ +int generic_ci_match(const struct inode *parent, + const struct qstr *name, + const struct qstr *folded_name, + const u8 *de_name, u32 de_name_len) +{ + const struct super_block *sb = parent->i_sb; + const struct unicode_map *um = sb->s_encoding; + struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len); + struct qstr dirent = QSTR_INIT(de_name, de_name_len); + int res, match = false; + + if (IS_ENCRYPTED(parent)) { + const struct fscrypt_str encrypted_name = + FSTR_INIT((u8 *) de_name, de_name_len); + + if (WARN_ON_ONCE(!fscrypt_has_encryption_key(parent))) + return -EINVAL; + + decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL); + if (!decrypted_name.name) + return -ENOMEM; + res = fscrypt_fname_disk_to_usr(parent, 0, 0, &encrypted_name, + &decrypted_name); + if (res < 0) + goto out; + dirent.name = decrypted_name.name; + dirent.len = decrypted_name.len; + } + + if (folded_name->name) + res = utf8_strncasecmp_folded(um, folded_name, &dirent); + else + res = utf8_strncasecmp(um, name, &dirent); + + if (!res) + match = true; + else if (res < 0 && !sb_has_strict_encoding(sb)) { + /* + * In non-strict mode, fallback to a byte comparison if + * the names have invalid characters. + */ + res = 0; + match = ((name->len == dirent.len) && + !memcmp(name->name, dirent.name, dirent.len)); + } + +out: + kfree(decrypted_name.name); + return (res >= 0) ? match : res; +} +EXPORT_SYMBOL(generic_ci_match); #endif #ifdef CONFIG_FS_ENCRYPTION diff --git a/include/linux/fs.h b/include/linux/fs.h index e2d892b201b0..4c2b781f667a 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3359,6 +3359,10 @@ extern int generic_file_fsync(struct file *, loff_t, loff_t, int); extern int generic_check_addressable(unsigned, u64); extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry); +extern int generic_ci_match(const struct inode *parent, + const struct qstr *name, + const struct qstr *folded_name, + const u8 *de_name, u32 de_name_len); #ifdef CONFIG_MIGRATION extern int buffer_migrate_page(struct address_space *, -- 2.36.1 From mboxrd@z Thu Jan 1 00:00:00 1970 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 lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9D55AC433F5 for ; Thu, 19 May 2022 21:24:26 +0000 (UTC) Received: from [127.0.0.1] (helo=sfs-ml-2.v29.lw.sourceforge.com) by sfs-ml-2.v29.lw.sourceforge.com with esmtp (Exim 4.94.2) (envelope-from ) id 1nrndC-0001to-Sn; Thu, 19 May 2022 21:24:26 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-2.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nrndA-0001tZ-Ee for linux-f2fs-devel@lists.sourceforge.net; Thu, 19 May 2022 21:24:23 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=JwBRujFCrvhEr0m+QCqDT7QAWT9ghEEbK544DO4Gw8Y=; b=f6RT89mNpHnlhQF3EMU8U/FCB7 TpHxi9VJ0TwOdzrMK0wV8yys7tNlhAEgIGYBX1kcNomeryOSjkvgPeAJ01u+RLWPLo9l79UI0p0Sy 8wchLDgPofZ4wsaCfyNiEwcY3xWaSFFH3DlNFEBS4hl8lOjLtbcuBtd5LHN4h5MB+omw=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=JwBRujFCrvhEr0m+QCqDT7QAWT9ghEEbK544DO4Gw8Y=; b=J9Zfe+IIru1/ka/v7P/THyFS/B Cx4mO1aKOh5BaT/Rtu6PKGE67lauw0SN08LQrQD3azp//xzwRKS+Ptu1+OqenNaII9ev/BS12iVVR NUC/hGtRrzjwjg33tFUV+OgUNHbk1qIs8hKFECCzBliqfkIMtq1Y1Zcr2WLhuNDD0bkM=; Received: from bhuna.collabora.co.uk ([46.235.227.227]) by sfi-mx-2.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.94.2) id 1nrnd7-0003um-V3 for linux-f2fs-devel@lists.sourceforge.net; Thu, 19 May 2022 21:24:23 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id 9860B1F45F78 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1652995455; bh=Yy1A6Vts7piejGKGGyulGEO3LNJA5px4YK35G29ueMA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZrHMsEOJmFvhEzs15aYh1tXDMkSgUiYF9tw3YjXTGH7RpE2sA8jmIevP7hjhGh9MK 7jbv6DEEGeQc9c2Zl5WJzWWwE7Rcvc8e5UlpviS3fmLEl6SQsZVQiSZcsNkYcvTrkH A1En0Uum1NcKRdibeG19DkaTTl6mnyDSQ8/o3XwE0NvuWHr60WFrk27vQ/kPVBff7I o3lGTbh3dErMDeHWD/vSIsuDgI5+W6hLDWZzvBMuub4sZgKON3KxjL9YeEU87+HDqX Zb3ASp2SZ6TXA2Reh3cqla1Kyac04aM52kdzS/2Vfmxog3oBN2K/RsJhluBvLL9Pli JNIKxwDNYAs0Q== From: Gabriel Krisman Bertazi To: tytso@mit.edu, adilger.kernel@dilger.ca, jaegeuk@kernel.org, ebiggers@kernel.org Date: Thu, 19 May 2022 17:23:54 -0400 Message-Id: <20220519212359.19442-4-krisman@collabora.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220519212359.19442-1-krisman@collabora.com> References: <20220519212359.19442-1-krisman@collabora.com> MIME-Version: 1.0 X-Headers-End: 1nrnd7-0003um-V3 Subject: [f2fs-dev] [PATCH v8 3/8] libfs: Introduce case-insensitive string comparison helper X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-ext4@vger.kernel.org, Gabriel Krisman Bertazi , kernel@collabora.com, Eric Biggers , linux-f2fs-devel@lists.sourceforge.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net generic_ci_match can be used by case-insensitive filesystems to compare strings under lookup with dirents in a case-insensitive way. This function is currently reimplemented by each filesystem supporting casefolding, so this reduces code duplication in filesystem-specific code. Reviewed-by: Eric Biggers Signed-off-by: Gabriel Krisman Bertazi --- Changes since v5: (eric) - Rename variable err -> res - Retype de_name_len from size_t to u32 - Bring WARN_ON_ONCE(!fscrypt_has_encryption_key) from f2fs implementation --- fs/libfs.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 4 +++ 2 files changed, 72 insertions(+) diff --git a/fs/libfs.c b/fs/libfs.c index 974125270a42..f1d88cd903f8 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1465,6 +1465,74 @@ static const struct dentry_operations generic_ci_dentry_ops = { .d_hash = generic_ci_d_hash, .d_compare = generic_ci_d_compare, }; + +/** + * generic_ci_match() - Match a name (case-insensitively) with a dirent. + * @parent: Inode of the parent of the dirent under comparison + * @name: name under lookup. + * @folded_name: Optional pre-folded name under lookup + * @de_name: Dirent name. + * @de_name_len: dirent name length. + * + * + * Test whether a case-insensitive directory entry matches the filename + * being searched. If @folded_name is provided, it is used instead of + * recalculating the casefold of @name. + * + * Return: > 0 if the directory entry matches, 0 if it doesn't match, or + * < 0 on error. + */ +int generic_ci_match(const struct inode *parent, + const struct qstr *name, + const struct qstr *folded_name, + const u8 *de_name, u32 de_name_len) +{ + const struct super_block *sb = parent->i_sb; + const struct unicode_map *um = sb->s_encoding; + struct fscrypt_str decrypted_name = FSTR_INIT(NULL, de_name_len); + struct qstr dirent = QSTR_INIT(de_name, de_name_len); + int res, match = false; + + if (IS_ENCRYPTED(parent)) { + const struct fscrypt_str encrypted_name = + FSTR_INIT((u8 *) de_name, de_name_len); + + if (WARN_ON_ONCE(!fscrypt_has_encryption_key(parent))) + return -EINVAL; + + decrypted_name.name = kmalloc(de_name_len, GFP_KERNEL); + if (!decrypted_name.name) + return -ENOMEM; + res = fscrypt_fname_disk_to_usr(parent, 0, 0, &encrypted_name, + &decrypted_name); + if (res < 0) + goto out; + dirent.name = decrypted_name.name; + dirent.len = decrypted_name.len; + } + + if (folded_name->name) + res = utf8_strncasecmp_folded(um, folded_name, &dirent); + else + res = utf8_strncasecmp(um, name, &dirent); + + if (!res) + match = true; + else if (res < 0 && !sb_has_strict_encoding(sb)) { + /* + * In non-strict mode, fallback to a byte comparison if + * the names have invalid characters. + */ + res = 0; + match = ((name->len == dirent.len) && + !memcmp(name->name, dirent.name, dirent.len)); + } + +out: + kfree(decrypted_name.name); + return (res >= 0) ? match : res; +} +EXPORT_SYMBOL(generic_ci_match); #endif #ifdef CONFIG_FS_ENCRYPTION diff --git a/include/linux/fs.h b/include/linux/fs.h index e2d892b201b0..4c2b781f667a 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3359,6 +3359,10 @@ extern int generic_file_fsync(struct file *, loff_t, loff_t, int); extern int generic_check_addressable(unsigned, u64); extern void generic_set_encrypted_ci_d_ops(struct dentry *dentry); +extern int generic_ci_match(const struct inode *parent, + const struct qstr *name, + const struct qstr *folded_name, + const u8 *de_name, u32 de_name_len); #ifdef CONFIG_MIGRATION extern int buffer_migrate_page(struct address_space *, -- 2.36.1 _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel