From patchwork Tue May 4 18:08:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Shevchenko X-Patchwork-Id: 12238421 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 32AF2C43460 for ; Tue, 4 May 2021 18:09:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0DE10613D8 for ; Tue, 4 May 2021 18:09:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232250AbhEDSKp (ORCPT ); Tue, 4 May 2021 14:10:45 -0400 Received: from mga17.intel.com ([192.55.52.151]:33853 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232257AbhEDSJF (ORCPT ); Tue, 4 May 2021 14:09:05 -0400 IronPort-SDR: GVYEer7655/pPEUbop6izsKFJwYpymkMIXsu28QbR7wfvf/SmUKINSYwaeddmZEEmYqoxat72D Plzqy+rh0cRg== X-IronPort-AV: E=McAfee;i="6200,9189,9974"; a="178258333" X-IronPort-AV: E=Sophos;i="5.82,272,1613462400"; d="scan'208";a="178258333" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 May 2021 11:08:09 -0700 IronPort-SDR: IpNDWNrOXjw3wGXjKQPsaoRPPhUSyNI4EdFKeRy451rHowTnuK60ee25hrnIdtTXRayXpAHPNg 9BMJSYrSh/YA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,272,1613462400"; d="scan'208";a="390052755" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga006.jf.intel.com with ESMTP; 04 May 2021 11:08:07 -0700 Received: by black.fi.intel.com (Postfix, from userid 1003) id D212D35E; 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 06/15] lib/string_helpers: Allow to append additional characters to be escaped Date: Tue, 4 May 2021 21:08:10 +0300 Message-Id: <20210504180819.73127-7-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 Introduce a new flag to append additional characters, passed in 'only' parameter, to be escaped if they fall in the corresponding class. Signed-off-by: Andy Shevchenko --- include/linux/string_helpers.h | 1 + lib/string_helpers.c | 19 +++++++++++++++---- 2 files changed, 16 insertions(+), 4 deletions(-) diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h index 811c6a627620..f8728ed4d563 100644 --- a/include/linux/string_helpers.h +++ b/include/linux/string_helpers.h @@ -54,6 +54,7 @@ static inline int string_unescape_any_inplace(char *buf) #define ESCAPE_HEX BIT(5) #define ESCAPE_NA BIT(6) #define ESCAPE_NAP BIT(7) +#define ESCAPE_APPEND BIT(8) 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 ceca5fbbd92c..c15aea7a82e9 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -493,6 +493,11 @@ static bool escape_hex(unsigned char c, char **dst, char *end) * escape only non-ascii characters, checked by isascii() * %ESCAPE_NAP: * escape only non-printable or non-ascii characters + * %ESCAPE_APPEND: + * append characters from @only to be escaped by the given classes + * + * %ESCAPE_APPEND would help to pass additional characters to the escaped, when + * one of %ESCAPE_NP, %ESCAPE_NA, or %ESCAPE_NAP is provided. * * 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). @@ -513,9 +518,11 @@ int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz, char *p = dst; char *end = p + osz; bool is_dict = only && *only; + bool is_append = flags & ESCAPE_APPEND; while (isz--) { unsigned char c = *src++; + bool in_dict = is_dict && strchr(only, c); /* * Apply rules in the following sequence: @@ -531,20 +538,24 @@ int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz, * defined by given @flags * In these cases we just pass through a character to the * output buffer. + * + * When %ESCAPE_APPEND is passed, the characters from @only + * have been excluded from the %ESCAPE_NAP, %ESCAPE_NP, and + * %ESCAPE_NA cases. */ - if (is_dict && !strchr(only, c) && + if (!(is_append || in_dict) && is_dict && escape_passthrough(c, &p, end)) continue; - if (isascii(c) && isprint(c) && + if (!(is_append && in_dict) && isascii(c) && isprint(c) && flags & ESCAPE_NAP && escape_passthrough(c, &p, end)) continue; - if (isprint(c) && + if (!(is_append && in_dict) && isprint(c) && flags & ESCAPE_NP && escape_passthrough(c, &p, end)) continue; - if (isascii(c) && + if (!(is_append && in_dict) && isascii(c) && flags & ESCAPE_NA && escape_passthrough(c, &p, end)) continue;