From patchwork Fri Sep 14 07:26:15 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 969641 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 42BRt524Pnz9s2P for ; Fri, 14 Sep 2018 17:27:09 +1000 (AEST) Received: from localhost ([::1]:49243 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g0iVO-0007r1-TP for incoming@patchwork.ozlabs.org; Fri, 14 Sep 2018 03:27:06 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35841) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g0iUo-0007pQ-OH for qemu-devel@nongnu.org; Fri, 14 Sep 2018 03:26:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g0iUm-0000P0-Ka for qemu-devel@nongnu.org; Fri, 14 Sep 2018 03:26:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37934) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g0iUk-0000KV-MV for qemu-devel@nongnu.org; Fri, 14 Sep 2018 03:26:28 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7C3BC3084218; Fri, 14 Sep 2018 07:26:24 +0000 (UTC) Received: from lemon.usersys.redhat.com (ovpn-12-180.pek2.redhat.com [10.72.12.180]) by smtp.corp.redhat.com (Postfix) with ESMTP id 51E185FC0A; Fri, 14 Sep 2018 07:26:23 +0000 (UTC) From: Fam Zheng To: qemu-devel@nongnu.org Date: Fri, 14 Sep 2018 15:26:15 +0800 Message-Id: <20180914072616.17771-2-famz@redhat.com> In-Reply-To: <20180914072616.17771-1-famz@redhat.com> References: <20180914072616.17771-1-famz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Fri, 14 Sep 2018 07:26:24 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3 1/2] slirp: Add sanity check for str option length 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: Samuel Thibault Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" When user provides a long domainname or hostname that doesn't fit in the DHCP packet, we mustn't overflow the response packet buffer. Instead, report errors, following the g_warning() in the slirp->vdnssearch branch. Also check the strlen against 256 when initializing slirp, which limit is also from the protocol where one byte represents the string length. This gives an early error before the warning which is harder to notice or diagnose. Reported-by: Thomas Huth Reviewed-by: Thomas Huth Cc: qemu-stable@nongnu.org Signed-off-by: Fam Zheng Tested-by: Gerd Hoffmann --- net/slirp.c | 9 +++++++++ slirp/bootp.c | 32 ++++++++++++++++++++++---------- 2 files changed, 31 insertions(+), 10 deletions(-) diff --git a/net/slirp.c b/net/slirp.c index 1e14318b4d..fd21dc728c 100644 --- a/net/slirp.c +++ b/net/slirp.c @@ -365,6 +365,15 @@ static int net_slirp_init(NetClientState *peer, const char *model, return -1; } + if (vdomainname && strlen(vdomainname) > 255) { + error_setg(errp, "'domainname' parameter cannot exceed 255 bytes"); + return -1; + } + + if (vhostname && strlen(vhostname) > 255) { + error_setg(errp, "'vhostname' parameter cannot exceed 255 bytes"); + return -1; + } nc = qemu_new_net_client(&net_slirp_info, peer, model, name); diff --git a/slirp/bootp.c b/slirp/bootp.c index 9e7b53ba94..1e8185f0ec 100644 --- a/slirp/bootp.c +++ b/slirp/bootp.c @@ -159,6 +159,7 @@ static void bootp_reply(Slirp *slirp, const struct bootp_t *bp) struct in_addr preq_addr; int dhcp_msg_type, val; uint8_t *q; + uint8_t *end; uint8_t client_ethaddr[ETH_ALEN]; /* extract exact DHCP msg type */ @@ -240,6 +241,7 @@ static void bootp_reply(Slirp *slirp, const struct bootp_t *bp) rbp->bp_siaddr = saddr.sin_addr; /* Server IP address */ q = rbp->bp_vend; + end = (uint8_t *)&rbp[1]; memcpy(q, rfc1533_cookie, 4); q += 4; @@ -292,24 +294,33 @@ static void bootp_reply(Slirp *slirp, const struct bootp_t *bp) if (*slirp->client_hostname) { val = strlen(slirp->client_hostname); - *q++ = RFC1533_HOSTNAME; - *q++ = val; - memcpy(q, slirp->client_hostname, val); - q += val; + if (q + val + 2 >= end) { + g_warning("DHCP packet size exceeded, " + "omitting host name option."); + } else { + *q++ = RFC1533_HOSTNAME; + *q++ = val; + memcpy(q, slirp->client_hostname, val); + q += val; + } } if (slirp->vdomainname) { val = strlen(slirp->vdomainname); - *q++ = RFC1533_DOMAINNAME; - *q++ = val; - memcpy(q, slirp->vdomainname, val); - q += val; + if (q + val + 2 >= end) { + g_warning("DHCP packet size exceeded, " + "omitting domain name option."); + } else { + *q++ = RFC1533_DOMAINNAME; + *q++ = val; + memcpy(q, slirp->vdomainname, val); + q += val; + } } if (slirp->vdnssearch) { - size_t spaceleft = sizeof(rbp->bp_vend) - (q - rbp->bp_vend); val = slirp->vdnssearch_len; - if (val + 1 > spaceleft) { + if (q + val >= end) { g_warning("DHCP packet size exceeded, " "omitting domain-search option."); } else { @@ -331,6 +342,7 @@ static void bootp_reply(Slirp *slirp, const struct bootp_t *bp) memcpy(q, nak_msg, sizeof(nak_msg) - 1); q += sizeof(nak_msg) - 1; } + assert(q < end); *q = RFC1533_END; daddr.sin_addr.s_addr = 0xffffffffu; From patchwork Fri Sep 14 07:26:16 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 969642 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 42BRwB4jcyz9s2P for ; Fri, 14 Sep 2018 17:28:58 +1000 (AEST) Received: from localhost ([::1]:49251 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g0iXA-0000oL-BX for incoming@patchwork.ozlabs.org; Fri, 14 Sep 2018 03:28:56 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35864) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g0iUr-0007qy-3X for qemu-devel@nongnu.org; Fri, 14 Sep 2018 03:26:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g0iUo-0000TN-RT for qemu-devel@nongnu.org; Fri, 14 Sep 2018 03:26:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37946) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g0iUm-0000M3-Jm for qemu-devel@nongnu.org; Fri, 14 Sep 2018 03:26:30 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3C144308421A; Fri, 14 Sep 2018 07:26:26 +0000 (UTC) Received: from lemon.usersys.redhat.com (ovpn-12-180.pek2.redhat.com [10.72.12.180]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0B14A5E1CF; Fri, 14 Sep 2018 07:26:24 +0000 (UTC) From: Fam Zheng To: qemu-devel@nongnu.org Date: Fri, 14 Sep 2018 15:26:16 +0800 Message-Id: <20180914072616.17771-3-famz@redhat.com> In-Reply-To: <20180914072616.17771-1-famz@redhat.com> References: <20180914072616.17771-1-famz@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Fri, 14 Sep 2018 07:26:26 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3 2/2] slirp: Implement RFC2132 TFTP server name 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: Samuel Thibault Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This new usernet option can be used to add data for option 66 (tftp server name) in the BOOTP reply, which is useful in PXE based automatic OS install such as OpenBSD. Signed-off-by: Fam Zheng Reviewed-by: Thomas Huth Tested-by: Gerd Hoffmann --- net/slirp.c | 12 ++++++++++-- qapi/net.json | 5 ++++- qemu-options.hx | 7 ++++++- slirp/bootp.c | 13 +++++++++++++ slirp/bootp.h | 1 + slirp/libslirp.h | 1 + slirp/slirp.c | 2 ++ slirp/slirp.h | 1 + 8 files changed, 38 insertions(+), 4 deletions(-) diff --git a/net/slirp.c b/net/slirp.c index fd21dc728c..53f7b89696 100644 --- a/net/slirp.c +++ b/net/slirp.c @@ -158,6 +158,7 @@ static int net_slirp_init(NetClientState *peer, const char *model, const char *vnameserver, const char *vnameserver6, const char *smb_export, const char *vsmbserver, const char **dnssearch, const char *vdomainname, + const char *tftp_server_name, Error **errp) { /* default settings according to historic slirp */ @@ -375,6 +376,11 @@ static int net_slirp_init(NetClientState *peer, const char *model, return -1; } + if (tftp_server_name && strlen(tftp_server_name) > 255) { + error_setg(errp, "'tftp-server-name' parameter cannot exceed 255 bytes"); + return -1; + } + nc = qemu_new_net_client(&net_slirp_info, peer, model, name); snprintf(nc->info_str, sizeof(nc->info_str), @@ -385,7 +391,8 @@ static int net_slirp_init(NetClientState *peer, const char *model, s->slirp = slirp_init(restricted, ipv4, net, mask, host, ipv6, ip6_prefix, vprefix6_len, ip6_host, - vhostname, tftp_export, bootfile, dhcp, + vhostname, tftp_server_name, + tftp_export, bootfile, dhcp, dns, ip6_dns, dnssearch, vdomainname, s); QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry); @@ -975,7 +982,8 @@ int net_init_slirp(const Netdev *netdev, const char *name, user->ipv6_host, user->hostname, user->tftp, user->bootfile, user->dhcpstart, user->dns, user->ipv6_dns, user->smb, - user->smbserver, dnssearch, user->domainname, errp); + user->smbserver, dnssearch, user->domainname, + user->tftp_server_name, errp); while (slirp_configs) { config = slirp_configs; diff --git a/qapi/net.json b/qapi/net.json index c86f351161..8f99fd911d 100644 --- a/qapi/net.json +++ b/qapi/net.json @@ -174,6 +174,8 @@ # # @guestfwd: forward guest TCP connections # +# @tftp-server-name: RFC2132 "TFTP server name" string (Since 3.1) +# # Since: 1.2 ## { 'struct': 'NetdevUserOptions', @@ -198,7 +200,8 @@ '*smb': 'str', '*smbserver': 'str', '*hostfwd': ['String'], - '*guestfwd': ['String'] } } + '*guestfwd': ['String'], + '*tftp-server-name': 'str' } } ## # @NetdevTapOptions: diff --git a/qemu-options.hx b/qemu-options.hx index 654ef484d9..2c2acbb14b 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -1842,7 +1842,7 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n" - " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]" + " [,tftp=dir][,tftp-server-name=name][,bootfile=f][,hostfwd=rule][,guestfwd=rule]" #ifndef _WIN32 "[,smb=dir[,smbserver=addr]]\n" #endif @@ -2079,6 +2079,11 @@ server. The files in @var{dir} will be exposed as the root of a TFTP server. The TFTP client on the guest must be configured in binary mode (use the command @code{bin} of the Unix TFTP client). +@item tftp-server-name=@var{name} +In BOOTP reply, broadcast @var{name} as the "TFTP server name" (RFC2132 option +66). This can be used to advise the guest to load boot files or configurations +from a different server than the host address. + @item bootfile=@var{file} When using the user mode network stack, broadcast @var{file} as the BOOTP filename. In conjunction with @option{tftp}, this can be used to network boot diff --git a/slirp/bootp.c b/slirp/bootp.c index 1e8185f0ec..7b1af73c95 100644 --- a/slirp/bootp.c +++ b/slirp/bootp.c @@ -318,6 +318,19 @@ static void bootp_reply(Slirp *slirp, const struct bootp_t *bp) } } + if (slirp->tftp_server_name) { + val = strlen(slirp->tftp_server_name); + if (q + val + 2 >= end) { + g_warning("DHCP packet size exceeded, " + "omitting tftp-server-name option."); + } else { + *q++ = RFC2132_TFTP_SERVER_NAME; + *q++ = val; + memcpy(q, slirp->tftp_server_name, val); + q += val; + } + } + if (slirp->vdnssearch) { val = slirp->vdnssearch_len; if (q + val >= end) { diff --git a/slirp/bootp.h b/slirp/bootp.h index 394525733e..4043489835 100644 --- a/slirp/bootp.h +++ b/slirp/bootp.h @@ -70,6 +70,7 @@ #define RFC2132_MAX_SIZE 57 #define RFC2132_RENEWAL_TIME 58 #define RFC2132_REBIND_TIME 59 +#define RFC2132_TFTP_SERVER_NAME 66 #define DHCPDISCOVER 1 #define DHCPOFFER 2 diff --git a/slirp/libslirp.h b/slirp/libslirp.h index 740408a96e..42e42e9a2a 100644 --- a/slirp/libslirp.h +++ b/slirp/libslirp.h @@ -13,6 +13,7 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct in_addr vnetwork, bool in6_enabled, struct in6_addr vprefix_addr6, uint8_t vprefix_len, struct in6_addr vhost6, const char *vhostname, + const char *tftp_server_name, const char *tftp_path, const char *bootfile, struct in_addr vdhcp_start, struct in_addr vnameserver, struct in6_addr vnameserver6, const char **vdnssearch, diff --git a/slirp/slirp.c b/slirp/slirp.c index 5c3bd6163f..51de41fc02 100644 --- a/slirp/slirp.c +++ b/slirp/slirp.c @@ -283,6 +283,7 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct in_addr vnetwork, bool in6_enabled, struct in6_addr vprefix_addr6, uint8_t vprefix_len, struct in6_addr vhost6, const char *vhostname, + const char *tftp_server_name, const char *tftp_path, const char *bootfile, struct in_addr vdhcp_start, struct in_addr vnameserver, struct in6_addr vnameserver6, const char **vdnssearch, @@ -321,6 +322,7 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct in_addr vnetwork, slirp->vdhcp_startaddr = vdhcp_start; slirp->vnameserver_addr = vnameserver; slirp->vnameserver_addr6 = vnameserver6; + slirp->tftp_server_name = g_strdup(tftp_server_name); if (vdnssearch) { translate_dnssearch(slirp, vdnssearch); diff --git a/slirp/slirp.h b/slirp/slirp.h index 10b410898a..b80725a0d6 100644 --- a/slirp/slirp.h +++ b/slirp/slirp.h @@ -212,6 +212,7 @@ struct Slirp { /* tftp states */ char *tftp_prefix; struct tftp_session tftp_sessions[TFTP_SESSIONS_MAX]; + char *tftp_server_name; ArpTable arp_table; NdpTable ndp_table;