From patchwork Tue May 4 18:08:09 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Shevchenko X-Patchwork-Id: 12238419 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,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 9D961C43600 for ; Tue, 4 May 2021 18:08:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 738E4613DB for ; Tue, 4 May 2021 18:08:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232279AbhEDSJ0 (ORCPT ); Tue, 4 May 2021 14:09:26 -0400 Received: from mga04.intel.com ([192.55.52.120]:43157 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232369AbhEDSJU (ORCPT ); Tue, 4 May 2021 14:09:20 -0400 IronPort-SDR: iblq22Th16vHjgTbCFEQWzQOXDuQVwPE4cwVBxwH4RklYNhHIm0DVbzGugZsKxyrZNecM1w7ID 1oCKTYIC9lng== X-IronPort-AV: E=McAfee;i="6200,9189,9974"; a="195997142" X-IronPort-AV: E=Sophos;i="5.82,272,1613462400"; d="scan'208";a="195997142" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 May 2021 11:08:09 -0700 IronPort-SDR: lo9M6W0jgVReKtO6JrQFQPsigrwiLS8ObJ4ML7WIchkrqwaUC6zT+T5q+fkM4XSJ10b07CtlKA sXqvP0S46Qqw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,272,1613462400"; d="scan'208";a="451366819" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga004.fm.intel.com with ESMTP; 04 May 2021 11:08:07 -0700 Received: by black.fi.intel.com (Postfix, from userid 1003) id C69A634F; Tue, 4 May 2021 21:08:23 +0300 (EEST) From: Andy Shevchenko To: "J. Bruce Fields" , Andy Shevchenko , linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: "J. Bruce Fields" , Chuck Lever , Alexander Viro , Andy Shevchenko , Andrew Morton Subject: [PATCH v3 05/15] lib/string_helpers: Introduce ESCAPE_NAP to escape non-ASCII and non-printable Date: Tue, 4 May 2021 21:08:09 +0300 Message-Id: <20210504180819.73127-6-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210504180819.73127-1-andriy.shevchenko@linux.intel.com> References: <20210504180819.73127-1-andriy.shevchenko@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Some users may want to have an ASCII based filter for printable only characters, provided by conjunction of isascii() and isprint() functions. Here is the addition of a such. Signed-off-by: Andy Shevchenko --- include/linux/string_helpers.h | 1 + lib/string_helpers.c | 20 ++++++++++++++++---- 2 files changed, 17 insertions(+), 4 deletions(-) diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h index d6cf6fe10f74..811c6a627620 100644 --- a/include/linux/string_helpers.h +++ b/include/linux/string_helpers.h @@ -53,6 +53,7 @@ static inline int string_unescape_any_inplace(char *buf) #define ESCAPE_ANY_NP (ESCAPE_ANY | ESCAPE_NP) #define ESCAPE_HEX BIT(5) #define ESCAPE_NA BIT(6) +#define ESCAPE_NAP BIT(7) int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz, unsigned int flags, const char *only); diff --git a/lib/string_helpers.c b/lib/string_helpers.c index a963404b8c16..ceca5fbbd92c 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -454,9 +454,11 @@ static bool escape_hex(unsigned char c, char **dst, char *end) * * 1. The character is not matched to the one from @only string and thus * must go as-is to the output. - * 2. The character is matched to the printable or ASCII class, if asked, + * 2. The character is matched to the printable and ASCII classes, if asked, * and in case of match it passes through to the output. - * 3. The character is checked if it falls into the class given by @flags. + * 3. The character is matched to the printable or ASCII class, if asked, + * and in case of match it passes through to the output. + * 4. The character is checked if it falls into the class given by @flags. * %ESCAPE_OCTAL and %ESCAPE_HEX are going last since they cover any * character. Note that they actually can't go together, otherwise * %ESCAPE_HEX will be ignored. @@ -489,11 +491,15 @@ static bool escape_hex(unsigned char c, char **dst, char *end) * '\xHH' - byte with hexadecimal value HH (2 digits) * %ESCAPE_NA: * escape only non-ascii characters, checked by isascii() + * %ESCAPE_NAP: + * escape only non-printable or non-ascii characters * - * One notable caveat, the %ESCAPE_NP and %ESCAPE_NA have higher priority - * than the rest of the flags (%ESCAPE_NP is higher than %ESCAPE_NA). + * One notable caveat, the %ESCAPE_NAP, %ESCAPE_NP and %ESCAPE_NA have the + * higher priority than the rest of the flags (%ESCAPE_NAP is the highest). * It doesn't make much sense to use either of them without %ESCAPE_OCTAL * or %ESCAPE_HEX, because they cover most of the other character classes. + * %ESCAPE_NAP can utilize %ESCAPE_SPACE or %ESCAPE_SPECIAL in addition to + * the above. * * Return: * The total size of the escaped output that would be generated for @@ -515,6 +521,8 @@ int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz, * Apply rules in the following sequence: * - the @only string is supplied and does not contain a * character under question + * - the character is printable and ASCII, when @flags has + * %ESCAPE_NAP bit set * - the character is printable, when @flags has * %ESCAPE_NP bit set * - the character is ASCII, when @flags has @@ -528,6 +536,10 @@ int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz, escape_passthrough(c, &p, end)) continue; + if (isascii(c) && isprint(c) && + flags & ESCAPE_NAP && escape_passthrough(c, &p, end)) + continue; + if (isprint(c) && flags & ESCAPE_NP && escape_passthrough(c, &p, end)) continue;