From patchwork Tue Jun 15 16:01:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Westphal X-Patchwork-Id: 1492339 X-Patchwork-Delegate: pablo@netfilter.org Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netfilter-devel-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4G4Ckh5V5rz9sW6 for ; Wed, 16 Jun 2021 02:02:20 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231303AbhFOQEY (ORCPT ); Tue, 15 Jun 2021 12:04:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33060 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231639AbhFOQEM (ORCPT ); Tue, 15 Jun 2021 12:04:12 -0400 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:12e:520::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 52F51C061574 for ; Tue, 15 Jun 2021 09:02:07 -0700 (PDT) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1ltBVt-0001K9-R0; Tue, 15 Jun 2021 18:02:05 +0200 From: Florian Westphal To: Cc: Florian Westphal Subject: [PATCH nft v2 2/3] payload: do not remove icmp echo dependency Date: Tue, 15 Jun 2021 18:01:50 +0200 Message-Id: <20210615160151.10594-3-fw@strlen.de> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210615160151.10594-1-fw@strlen.de> References: <20210615160151.10594-1-fw@strlen.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org "icmp type echo-request icmp id 2" and "icmp id 2" are not the same, the latter gains an implicit dependency on both echo-request and echo-reply. Change payload dependency tracking to not store dependency in case the value type is ICMP(6)_ECHO(REPLY). Signed-off-by: Florian Westphal --- src/payload.c | 61 +++++++++++++++++++++++++++++++-------------------- 1 file changed, 37 insertions(+), 24 deletions(-) diff --git a/src/payload.c b/src/payload.c index cfa952248a15..97b60713e800 100644 --- a/src/payload.c +++ b/src/payload.c @@ -98,12 +98,16 @@ static void payload_expr_pctx_update(struct proto_ctx *ctx, desc = proto_find_upper(base, proto); if (!desc) { - if (base == &proto_icmp || base == &proto_icmp6) { + if (base == &proto_icmp) { /* proto 0 is ECHOREPLY, just pretend its ECHO. * Not doing this would need an additional marker * bit to tell when icmp.type was set. */ ctx->th_dep.icmp.type = proto ? proto : ICMP_ECHO; + } else if (base == &proto_icmp6) { + if (proto == ICMP6_ECHO_REPLY) + proto = ICMP6_ECHO_REQUEST; + ctx->th_dep.icmp.type = proto; } return; } @@ -554,33 +558,39 @@ void payload_dependency_reset(struct payload_dep_ctx *ctx) memset(ctx, 0, sizeof(*ctx)); } -static uint8_t icmp_get_type(const struct proto_desc *desc, uint8_t value) +static bool payload_dependency_store_icmp_type(struct payload_dep_ctx *ctx, + const struct stmt *stmt) { - if (desc == &proto_icmp && value == 0) - return ICMP_ECHO; + struct expr *dep = stmt->expr; + const struct proto_desc *desc; + const struct expr *right; + uint8_t type; - return value; -} + if (dep->left->etype != EXPR_PAYLOAD) + return false; -static uint8_t icmp_get_dep_type(const struct proto_desc *desc, struct expr *right) -{ - if (right->etype == EXPR_VALUE && right->len == BITS_PER_BYTE) - return icmp_get_type(desc, mpz_get_uint8(right->value)); + right = dep->right; + if (right->etype != EXPR_VALUE || right->len != BITS_PER_BYTE) + return false; - return 0; -} + desc = dep->left->payload.desc; + if (desc == &proto_icmp) { + type = mpz_get_uint8(right->value); -static void payload_dependency_store_icmp_type(struct payload_dep_ctx *ctx) -{ - struct expr *dep = ctx->pdep->expr; - const struct proto_desc *desc; + if (type == ICMP_ECHOREPLY) + type = ICMP_ECHO; - if (dep->left->etype != EXPR_PAYLOAD) - return; + ctx->icmp_type = type; - desc = dep->left->payload.desc; - if (desc == &proto_icmp || desc == &proto_icmp6) - ctx->icmp_type = icmp_get_dep_type(dep->left->payload.desc, dep->right); + return type == ICMP_ECHO; + } else if (desc == &proto_icmp6) { + type = mpz_get_uint8(right->value); + + ctx->icmp_type = type; + return type == ICMP6_ECHO_REQUEST || type == ICMP6_ECHO_REPLY; + } + + return false; } /** @@ -593,10 +603,13 @@ static void payload_dependency_store_icmp_type(struct payload_dep_ctx *ctx) void payload_dependency_store(struct payload_dep_ctx *ctx, struct stmt *stmt, enum proto_bases base) { - ctx->pbase = base + 1; - ctx->pdep = stmt; + bool ignore_dep = payload_dependency_store_icmp_type(ctx, stmt); + + if (ignore_dep) + return; - payload_dependency_store_icmp_type(ctx); + ctx->pdep = stmt; + ctx->pbase = base + 1; } /**