From nobody Fri Nov 7 13:04:07 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1538935733374484.084152258607; Sun, 7 Oct 2018 11:08:53 -0700 (PDT) Received: from localhost ([::1]:43144 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g9DU3-0002C9-Bh for importer@patchew.org; Sun, 07 Oct 2018 14:08:51 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54608) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g9DQp-0008VL-8z for qemu-devel@nongnu.org; Sun, 07 Oct 2018 14:05:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g9DQo-00017i-8a for qemu-devel@nongnu.org; Sun, 07 Oct 2018 14:05:31 -0400 Received: from hera.aquilenet.fr ([2a0c:e300::1]:54644) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g9DQn-0000wv-Lo for qemu-devel@nongnu.org; Sun, 07 Oct 2018 14:05:29 -0400 Received: from localhost (localhost [127.0.0.1]) by hera.aquilenet.fr (Postfix) with ESMTP id 013E24A4; Sun, 7 Oct 2018 20:05:21 +0200 (CEST) Received: from hera.aquilenet.fr ([127.0.0.1]) by localhost (hera.aquilenet.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id cb1vOvp_vShb; Sun, 7 Oct 2018 20:05:20 +0200 (CEST) Received: from var.youpi.perso.aquilenet.fr (unknown [IPv6:2a01:cb19:181:c200:3602:86ff:fe2c:6a19]) by hera.aquilenet.fr (Postfix) with ESMTPSA id 4DAD4CEB; Sun, 7 Oct 2018 20:05:19 +0200 (CEST) Received: from samy by var.youpi.perso.aquilenet.fr with local (Exim 4.91) (envelope-from ) id 1g9DQc-0001Ms-Cc; Sun, 07 Oct 2018 20:05:18 +0200 X-Virus-Scanned: Debian amavisd-new at aquilenet.fr From: Samuel Thibault To: qemu-devel@nongnu.org, peter.maydell@linaro.org Date: Sun, 7 Oct 2018 20:05:17 +0200 Message-Id: <20181007180518.5212-3-samuel.thibault@ens-lyon.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181007180518.5212-1-samuel.thibault@ens-lyon.org> References: <20181007180518.5212-1-samuel.thibault@ens-lyon.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2a0c:e300::1 Subject: [Qemu-devel] [PULL 2/3] slirp: fix ICMP handling on macOS hosts X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andrew Oates , jan.kiszka@siemens.com, stefanha@redhat.com, Samuel Thibault Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" From: Andrew Oates On Linux, SOCK_DGRAM+IPPROTO_ICMP sockets give only the ICMP packet when read from. On macOS, however, the socket acts like a SOCK_RAW socket and includes the IP header as well. This change strips the extra IP header from the received packet on macOS before sending it to the guest. SOCK_DGRAM ICMP sockets aren't supported on other BSDs, but we enable this behavior for them as well to treat the sockets the same as raw sockets. Signed-off-by: Andrew Oates Signed-off-by: Samuel Thibault --- slirp/ip_icmp.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/slirp/ip_icmp.c b/slirp/ip_icmp.c index 0b667a429a..da100d1f55 100644 --- a/slirp/ip_icmp.c +++ b/slirp/ip_icmp.c @@ -420,7 +420,32 @@ void icmp_receive(struct socket *so) icp =3D mtod(m, struct icmp *); =20 id =3D icp->icmp_id; - len =3D qemu_recv(so->s, icp, m->m_len, 0); + len =3D qemu_recv(so->s, icp, M_ROOM(m), 0); + /* + * The behavior of reading SOCK_DGRAM+IPPROTO_ICMP sockets is inconsis= tent + * between host OSes. On Linux, only the ICMP header and payload is + * included. On macOS/Darwin, the socket acts like a raw socket and + * includes the IP header as well. On other BSDs, SOCK_DGRAM+IPPROTO_= ICMP + * sockets aren't supported at all, so we treat them like raw sockets.= It + * isn't possible to detect this difference at runtime, so we must use= an + * #ifdef to determine if we need to remove the IP header. + */ +#ifdef CONFIG_BSD + if (len >=3D sizeof(struct ip)) { + struct ip *inner_ip =3D mtod(m, struct ip *); + int inner_hlen =3D inner_ip->ip_hl << 2; + if (inner_hlen > len) { + len =3D -1; + errno =3D -EINVAL; + } else { + len -=3D inner_hlen; + memmove(icp, (unsigned char *)icp + inner_hlen, len); + } + } else { + len =3D -1; + errno =3D -EINVAL; + } +#endif icp->icmp_id =3D id; =20 m->m_data -=3D hlen; --=20 2.19.0