From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57207) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fNuK7-0007G6-8K for qemu-devel@nongnu.org; Wed, 30 May 2018 02:11:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fNuK2-00068n-9t for qemu-devel@nongnu.org; Wed, 30 May 2018 02:11:01 -0400 Received: from 3.mo173.mail-out.ovh.net ([46.105.34.1]:41297) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fNuK2-000683-40 for qemu-devel@nongnu.org; Wed, 30 May 2018 02:10:58 -0400 Received: from player168.ha.ovh.net (unknown [10.109.122.102]) by mo173.mail-out.ovh.net (Postfix) with ESMTP id 5864CC0DC2 for ; Wed, 30 May 2018 08:10:56 +0200 (CEST) From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= Date: Wed, 30 May 2018 08:10:35 +0200 Message-Id: <20180530061035.22592-4-clg@kaod.org> In-Reply-To: <20180530061035.22592-1-clg@kaod.org> References: <20180530061035.22592-1-clg@kaod.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v2 3/3] slirp/ncsi: add checksum support List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Samuel Thibault Cc: qemu-devel@nongnu.org, =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= The checksum field of a NC-SI packet contains a value that may be included in each command and response. The verification is optional but the Linux driver does so when a non-zero value is provided. Let's extend the model to compute the checksum value and exercise a little more the Linux driver. See section "8.2.2.3 - 2's Complement Checksum Compensation" in the Network Controller Sideband Interface (NC-SI) Specification for more details. Signed-off-by: C=C3=A9dric Le Goater Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- Changes since v1: - updated Copyright - used uint16_t instead of chars to compute the checksum =20 slirp/ncsi.c | 33 ++++++++++++++++++++++++++++----- 1 file changed, 28 insertions(+), 5 deletions(-) diff --git a/slirp/ncsi.c b/slirp/ncsi.c index 7b3fff207ab3..7116034afc20 100644 --- a/slirp/ncsi.c +++ b/slirp/ncsi.c @@ -1,7 +1,7 @@ /* * NC-SI (Network Controller Sideband Interface) "echo" model * - * Copyright (C) 2016 IBM Corp. + * Copyright (C) 2016-2018 IBM Corp. * * This code is licensed under the GPL version 2 or later. See the * COPYING file in the top-level directory. @@ -11,6 +11,23 @@ =20 #include "ncsi-pkt.h" =20 +static uint32_t ncsi_calculate_checksum(uint16_t *data, int len) +{ + uint32_t checksum =3D 0; + int i; + + /* + * 32-bit unsigned sum of the NC-SI packet header and NC-SI packet + * payload interpreted as a series of 16-bit unsigned integer values= . + */ + for (i =3D 0; i < len; i++) { + checksum +=3D htons(data[i]); + } + + checksum =3D (~checksum + 1); + return checksum; +} + /* Get Capabilities */ static int ncsi_rsp_handler_gc(struct ncsi_rsp_pkt_hdr *rnh) { @@ -101,6 +118,9 @@ void ncsi_input(Slirp *slirp, const uint8_t *pkt, int= pkt_len) (ncsi_reply + ETH_HLEN); const struct ncsi_rsp_handler *handler =3D NULL; int i; + int ncsi_rsp_len =3D sizeof(*nh); + uint32_t checksum; + uint32_t *pchecksum; =20 memset(ncsi_reply, 0, sizeof(ncsi_reply)); =20 @@ -130,15 +150,18 @@ void ncsi_input(Slirp *slirp, const uint8_t *pkt, i= nt pkt_len) /* TODO: handle errors */ handler->handler(rnh); } + ncsi_rsp_len +=3D handler->payload; } else { rnh->common.length =3D 0; rnh->code =3D htons(NCSI_PKT_RSP_C_UNAVAILABLE); rnh->reason =3D htons(NCSI_PKT_RSP_R_UNKNOWN); } =20 - /* TODO: add a checksum at the end of the frame but the specs - * allows it to be zero */ + /* Add the optional checksum at the end of the frame. */ + checksum =3D ncsi_calculate_checksum((uint16_t *) rnh, ncsi_rsp_len)= ; + pchecksum =3D (uint32_t *)((void *) rnh + ncsi_rsp_len); + *pchecksum =3D htonl(checksum); + ncsi_rsp_len +=3D 4; =20 - slirp_output(slirp->opaque, ncsi_reply, ETH_HLEN + sizeof(*nh) + - (handler ? handler->payload : 0) + 4); + slirp_output(slirp->opaque, ncsi_reply, ETH_HLEN + ncsi_rsp_len); } --=20 2.13.6