From patchwork Mon Jun 19 10:57:35 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heng Qi X-Patchwork-Id: 13284347 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0242CC8E3; Mon, 19 Jun 2023 10:57:46 +0000 (UTC) Received: from out30-131.freemail.mail.aliyun.com (out30-131.freemail.mail.aliyun.com [115.124.30.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DD6A173A; Mon, 19 Jun 2023 03:57:44 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045176;MF=hengqi@linux.alibaba.com;NM=1;PH=DS;RN=13;SR=0;TI=SMTPD_---0VlVN0ua_1687172259; Received: from localhost(mailfrom:hengqi@linux.alibaba.com fp:SMTPD_---0VlVN0ua_1687172259) by smtp.aliyun-inc.com; Mon, 19 Jun 2023 18:57:40 +0800 From: Heng Qi To: netdev@vger.kernel.org, bpf@vger.kernel.org Cc: "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend Subject: [PATCH net-next 1/4] virtio-net: a helper for probing the pseudo-header checksum Date: Mon, 19 Jun 2023 18:57:35 +0800 Message-Id: <20230619105738.117733-2-hengqi@linux.alibaba.com> X-Mailer: git-send-email 2.19.1.6.gb485710b In-Reply-To: <20230619105738.117733-1-hengqi@linux.alibaba.com> References: <20230619105738.117733-1-hengqi@linux.alibaba.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-9.9 required=5.0 tests=BAYES_00, ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE,UNPARSEABLE_RELAY,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org This helper parses UDP/TCP and calculates the pseudo-header checksum for virtio-net. virtio-net currently does not support insertion/deletion of VLANs nor SCTP checksum offloading. Signed-off-by: Heng Qi Reviewed-by: Xuan Zhuo --- drivers/net/virtio_net.c | 95 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 5a7f7a76b920..36cae78f6311 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1568,6 +1568,101 @@ static void virtio_skb_set_hash(const struct virtio_net_hdr_v1_hash *hdr_hash, skb_set_hash(skb, __le32_to_cpu(hdr_hash->hash_value), rss_hash_type); } +static int virtnet_flow_dissect_udp_tcp(struct virtnet_info *vi, struct sk_buff *skb) +{ + struct net_device *dev = vi->dev; + struct flow_keys_basic keys; + struct udphdr *uh; + struct tcphdr *th; + int len, offset; + + /* The flow dissector needs this information. */ + skb->dev = dev; + skb_reset_mac_header(skb); + skb->protocol = dev_parse_header_protocol(skb); + /* virtio-net does not need to resolve VLAN. */ + skb_set_network_header(skb, ETH_HLEN); + if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys, + NULL, 0, 0, 0, 0)) + return -EINVAL; + + /* 1. Pseudo-header checksum calculation requires: + * (1) saddr/daddr (2) IP_PROTO (3) length of transport payload + * 2. We don't parse SCTP because virtio-net currently doesn't + * support CRC offloading for SCTP. + */ + if (keys.basic.n_proto == htons(ETH_P_IP)) { + struct iphdr *iph; + + /* Flow dissector has verified that there is an IP header. */ + iph = ip_hdr(skb); + if (iph->version != 4 || !pskb_may_pull(skb, iph->ihl * 4)) + return -EINVAL; + + skb->transport_header = skb->mac_header + keys.control.thoff; + offset = skb_transport_offset(skb); + len = skb->len - offset; + if (keys.basic.ip_proto == IPPROTO_UDP) { + if (!pskb_may_pull(skb, offset + sizeof(struct udphdr))) + return -EINVAL; + + uh = udp_hdr(skb); + skb->csum_offset = offsetof(struct udphdr, check); + /* Although uh->len is already the 3rd parameter for the calculation + * of the pseudo-header checksum, we have already calculated the + * length of the transport layer, so use 'len' here directly. + */ + uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, len, + IPPROTO_UDP, 0); + } else if (keys.basic.ip_proto == IPPROTO_TCP) { + if (!pskb_may_pull(skb, offset + sizeof(struct tcphdr))) + return -EINVAL; + + th = tcp_hdr(skb); + skb->csum_offset = offsetof(struct tcphdr, check); + th->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, len, + IPPROTO_TCP, 0); + } /* virtio-net doesn't support checksums for SCTP hw offloading.*/ + } else if (keys.basic.n_proto == htons(ETH_P_IPV6)) { + struct ipv6hdr *ip6h; + + ip6h = ipv6_hdr(skb); + if (ip6h->version != 6) + return -EINVAL; + + /* We have skipped the possible extension headers for IPv6. + * If there is a Routing Header, the tx's check value is calculated by + * final_dst, and that value is the rx's daddr. + */ + skb->transport_header = skb->mac_header + keys.control.thoff; + offset = skb_transport_offset(skb); + len = skb->len - offset; + if (keys.basic.ip_proto == IPPROTO_UDP) { + if (!pskb_may_pull(skb, offset + sizeof(struct udphdr))) + return -EINVAL; + + uh = udp_hdr(skb); + skb->csum_offset = offsetof(struct udphdr, check); + uh->check = ~csum_ipv6_magic((const struct in6_addr *)&ip6h->saddr, + (const struct in6_addr *)&ip6h->daddr, + len, IPPROTO_UDP, 0); + } else if (keys.basic.ip_proto == IPPROTO_TCP) { + if (!pskb_may_pull(skb, offset + sizeof(struct tcphdr))) + return -EINVAL; + + th = tcp_hdr(skb); + skb->csum_offset = offsetof(struct tcphdr, check); + th->check = ~csum_ipv6_magic((const struct in6_addr *)&ip6h->saddr, + (const struct in6_addr *)&ip6h->daddr, + len, IPPROTO_TCP, 0); + } + } + + skb->csum_start = skb->transport_header; + + return 0; +} + static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq, void *buf, unsigned int len, void **ctx, unsigned int *xdp_xmit,