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 06080C64EC7 for ; Wed, 15 Feb 2023 20:50:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230142AbjBOUt6 (ORCPT ); Wed, 15 Feb 2023 15:49:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33622 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230045AbjBOUtL (ORCPT ); Wed, 15 Feb 2023 15:49:11 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E0DF1457C2; Wed, 15 Feb 2023 12:47:21 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B8E1EB823C1; Wed, 15 Feb 2023 20:46:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 25AD9C433A0; Wed, 15 Feb 2023 20:46:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1676493999; bh=Opj6eH/PliGR/czkKYVyeh+3acJCOj17iG8oS3E6I+A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P6kt12aQjprUX3sybEr8ahI41lIEczB8MZQtUUn/A4aiZdu/9EF21vc3sAIEv9q2f gM9qJ95y2VKd4mbHedu2Y6wNDnRN6bP+BQV3IpcmpMKkVM8jV1kol/xpfWALJj6XsN 6lu/Z+iAQqo9fpSTZ7xTfxjzymA1yeaxMl2d5IvXQ86e/LpZA7/l1N4HgHJepuLFWc 76Ny4mHS5o3VfNdCZhQjR3nif/dWoJS0l2KYW4ieT1CIeky0yfQ4ZMwumqsHV6Aa2o FK+6ABGsASJlA+Z2SauSbLStAratvg7u4qIoQa8E+GxnOEcHyWkwyf+XmzWi/cogpw a/QRNwUf52Btw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Benedict Wong , Steffen Klassert , Sasha Levin , davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 02/12] Fix XFRM-I support for nested ESP tunnels Date: Wed, 15 Feb 2023 15:46:24 -0500 Message-Id: <20230215204637.2761073-2-sashal@kernel.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230215204637.2761073-1-sashal@kernel.org> References: <20230215204637.2761073-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Benedict Wong [ Upstream commit b0355dbbf13c0052931dd14c38c789efed64d3de ] This change adds support for nested IPsec tunnels by ensuring that XFRM-I verifies existing policies before decapsulating a subsequent policies. Addtionally, this clears the secpath entries after policies are verified, ensuring that previous tunnels with no-longer-valid do not pollute subsequent policy checks. This is necessary especially for nested tunnels, as the IP addresses, protocol and ports may all change, thus not matching the previous policies. In order to ensure that packets match the relevant inbound templates, the xfrm_policy_check should be done before handing off to the inner XFRM protocol to decrypt and decapsulate. Notably, raw ESP/AH packets did not perform policy checks inherently, whereas all other encapsulated packets (UDP, TCP encapsulated) do policy checks after calling xfrm_input handling in the respective encapsulation layer. Test: Verified with additional Android Kernel Unit tests Signed-off-by: Benedict Wong Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin --- net/xfrm/xfrm_interface.c | 54 ++++++++++++++++++++++++++++++++++++--- net/xfrm/xfrm_policy.c | 3 +++ 2 files changed, 53 insertions(+), 4 deletions(-) diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c index 1e8b26eecb3f8..694eec6ca147e 100644 --- a/net/xfrm/xfrm_interface.c +++ b/net/xfrm/xfrm_interface.c @@ -207,6 +207,52 @@ static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet) skb->mark = 0; } +static int xfrmi_input(struct sk_buff *skb, int nexthdr, __be32 spi, + int encap_type, unsigned short family) +{ + struct sec_path *sp; + + sp = skb_sec_path(skb); + if (sp && (sp->len || sp->olen) && + !xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family)) + goto discard; + + XFRM_SPI_SKB_CB(skb)->family = family; + if (family == AF_INET) { + XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); + XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; + } else { + XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); + XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL; + } + + return xfrm_input(skb, nexthdr, spi, encap_type); +discard: + kfree_skb(skb); + return 0; +} + +static int xfrmi4_rcv(struct sk_buff *skb) +{ + return xfrmi_input(skb, ip_hdr(skb)->protocol, 0, 0, AF_INET); +} + +static int xfrmi6_rcv(struct sk_buff *skb) +{ + return xfrmi_input(skb, skb_network_header(skb)[IP6CB(skb)->nhoff], + 0, 0, AF_INET6); +} + +static int xfrmi4_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) +{ + return xfrmi_input(skb, nexthdr, spi, encap_type, AF_INET); +} + +static int xfrmi6_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) +{ + return xfrmi_input(skb, nexthdr, spi, encap_type, AF_INET6); +} + static int xfrmi_rcv_cb(struct sk_buff *skb, int err) { const struct xfrm_mode *inner_mode; @@ -774,8 +820,8 @@ static struct pernet_operations xfrmi_net_ops = { }; static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = { - .handler = xfrm6_rcv, - .input_handler = xfrm_input, + .handler = xfrmi6_rcv, + .input_handler = xfrmi6_input, .cb_handler = xfrmi_rcv_cb, .err_handler = xfrmi6_err, .priority = 10, @@ -825,8 +871,8 @@ static struct xfrm6_tunnel xfrmi_ip6ip_handler __read_mostly = { #endif static struct xfrm4_protocol xfrmi_esp4_protocol __read_mostly = { - .handler = xfrm4_rcv, - .input_handler = xfrm_input, + .handler = xfrmi4_rcv, + .input_handler = xfrmi4_input, .cb_handler = xfrmi_rcv_cb, .err_handler = xfrmi4_err, .priority = 10, diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index ba58b963f4827..0540e9f72b2fe 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -3669,6 +3669,9 @@ int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, goto reject; } + if (if_id) + secpath_reset(skb); + xfrm_pols_put(pols, npols); return 1; } -- 2.39.0