From patchwork Mon Apr 1 15:32:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alan Maguire X-Patchwork-Id: 10880161 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 52E7414DE for ; Mon, 1 Apr 2019 15:33:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3CFDC285BE for ; Mon, 1 Apr 2019 15:33:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 30AB428779; Mon, 1 Apr 2019 15:33:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B049F285BE for ; Mon, 1 Apr 2019 15:33:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728255AbfDAPda (ORCPT ); Mon, 1 Apr 2019 11:33:30 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:60200 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726514AbfDAPda (ORCPT ); Mon, 1 Apr 2019 11:33:30 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x31FTK2I040180; Mon, 1 Apr 2019 15:33:05 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2018-07-02; bh=VoMXM1QWgyjyznRLlltmKjzTr7D78C6JCyvieJydhNE=; b=ReW0ntEH4VEhrA6C31oTasjuB5E7o+QAdF0Uf18khMo1mXAe0sRB0RVFwNRLuQElSJrH O0PG3zPaaBa7fXDN4vRfLkyUhH9T4K53FqZbEJZF/PY0P8J0z5c9T4ZMUwXPE5OfmbTv rmXVzlwQFEpowzskJnPEZJXVQrWs0DtYBLgUNCbAZ4KfXKLP0+C1lHxi5zjF5m3iJ8H+ BW4hQjXwjtdIklhAxik2F0w9Ut1pqz74lzuPMNJ1+AVXJDpVJKIfAbxYzASNmSONL0oU h4/vNhj1JxA88Rzn7L0T/JpM8bqcZQ+DuS0vwj2ZtqZN1lcDWrr//tlj8Bd5orNd4rnn xA== Received: from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71]) by userp2130.oracle.com with ESMTP id 2rhyvsyu32-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 01 Apr 2019 15:33:05 +0000 Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id x31FWttk028990 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 1 Apr 2019 15:32:55 GMT Received: from abhmp0022.oracle.com (abhmp0022.oracle.com [141.146.116.28]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x31FWsfk015704; Mon, 1 Apr 2019 15:32:54 GMT Received: from dhcp-10-175-171-252.vpn.oracle.com (/10.175.171.252) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 01 Apr 2019 08:32:53 -0700 From: Alan Maguire To: willemb@google.com, ast@kernel.org, daniel@iogearbox.net, davem@davemloft.net, shuah@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, quentin.monnet@netronome.com, john.fastabend@gmail.com, rdna@fb.com, linux-kselftest@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org Cc: Alan Maguire Subject: [PATCH bpf-next 2/4] bpf: add layer 2 encap support to bpf_skb_adjust_room Date: Mon, 1 Apr 2019 16:32:09 +0100 Message-Id: <1554132731-3095-3-git-send-email-alan.maguire@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1554132731-3095-1-git-send-email-alan.maguire@oracle.com> References: <1554132731-3095-1-git-send-email-alan.maguire@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9214 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=3 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1904010104 Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In commit 868d523535c2 ("bpf: add bpf_skb_adjust_room encap flags") ...Willem introduced support to bpf_skb_adjust_room for GSO-friendly GRE and UDP encapsulation. For GSO to work for skbs, the inner headers (mac and network) need to be marked. For L3 encapsulation using bpf_skb_adjust_room, the mac and network headers are identical. Here we provide a way of specifying the inner mac header length for cases where L2 encap is desired. Such an approach can support encapsulated ethernet headers, MPLS headers etc. For example to convert from a packet of form [eth][ip][tcp] to [eth][ip][udp][inner mac][ip][tcp], something like the following could be done: headroom = sizeof(iph) + sizeof(struct udphdr) + inner_maclen; ret = bpf_skb_adjust_room(skb, headroom, BPF_ADJ_ROOM_MAC, BPF_F_ADJ_ROOM_ENCAP_L4_UDP | BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 | BPF_F_ADJ_ROOM_ENCAP_L2(inner_maclen)); Signed-off-by: Alan Maguire --- include/uapi/linux/bpf.h | 5 +++++ net/core/filter.c | 19 ++++++++++++++----- 2 files changed, 19 insertions(+), 5 deletions(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 8370245..6d8346a 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1500,6 +1500,10 @@ struct bpf_stack_build_id { * * **BPF_F_ADJ_ROOM_ENCAP_L4_UDP **: * Use with ENCAP_L3 flags to further specify the tunnel type. * + * * **BPF_F_ADJ_ROOM_ENCAP_L2(len) **: + * Use with ENCAP_L3/L4 flags to further specify the tunnel + * type; **len** is the length of the inner MAC header. + * * A call to this helper is susceptible to change the underlaying * packet buffer. Therefore, at load time, all checks on pointers * previously done by the verifier are invalidated and must be @@ -2645,6 +2649,7 @@ enum bpf_func_id { #define BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 (1ULL << 2) #define BPF_F_ADJ_ROOM_ENCAP_L4_GRE (1ULL << 3) #define BPF_F_ADJ_ROOM_ENCAP_L4_UDP (1ULL << 4) +#define BPF_F_ADJ_ROOM_ENCAP_L2(len) (((__u64)len & 0xff) << 56) /* Mode for BPF_FUNC_skb_adjust_room helper. */ enum bpf_adj_room_mode { diff --git a/net/core/filter.c b/net/core/filter.c index 22eb2ed..02ae8c0 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2969,14 +2969,16 @@ static u32 bpf_skb_net_base_len(const struct sk_buff *skb) #define BPF_F_ADJ_ROOM_MASK (BPF_F_ADJ_ROOM_FIXED_GSO | \ BPF_F_ADJ_ROOM_ENCAP_L3_MASK | \ BPF_F_ADJ_ROOM_ENCAP_L4_GRE | \ - BPF_F_ADJ_ROOM_ENCAP_L4_UDP) + BPF_F_ADJ_ROOM_ENCAP_L4_UDP | \ + BPF_F_ADJ_ROOM_ENCAP_L2(0xff)) static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff, u64 flags) { + u16 mac_len = 0, inner_mac = 0, inner_net = 0, inner_trans = 0; bool encap = flags & BPF_F_ADJ_ROOM_ENCAP_L3_MASK; - u16 mac_len = 0, inner_net = 0, inner_trans = 0; unsigned int gso_type = SKB_GSO_DODGY; + u8 inner_mac_len = flags >> 56; int ret; if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) { @@ -3003,11 +3005,19 @@ static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff, flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP) return -EINVAL; + if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP && + flags & BPF_F_ADJ_ROOM_FIXED_GSO && + inner_mac_len > 0) + return -EINVAL; + if (skb->encapsulation) return -EALREADY; mac_len = skb->network_header - skb->mac_header; inner_net = skb->network_header; + if (inner_mac_len > len_diff) + return -EINVAL; + inner_mac = inner_net - inner_mac_len; inner_trans = skb->transport_header; } @@ -3016,8 +3026,7 @@ static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff, return ret; if (encap) { - /* inner mac == inner_net on l3 encap */ - skb->inner_mac_header = inner_net; + skb->inner_mac_header = inner_mac; skb->inner_network_header = inner_net; skb->inner_transport_header = inner_trans; skb_set_inner_protocol(skb, skb->protocol); @@ -3031,7 +3040,7 @@ static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff, gso_type |= SKB_GSO_GRE; else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6) gso_type |= SKB_GSO_IPXIP6; - else + else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4) gso_type |= SKB_GSO_IPXIP4; if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE ||