From 5108bbaddc37c1c8583f0cf2562d7d3463cd12cb Mon Sep 17 00:00:00 2001 From: Jiri Benc Date: Thu, 10 Nov 2016 16:28:21 +0100 Subject: [PATCH] openvswitch: add processing of L3 packets Support receiving, extracting flow key and sending of L3 packets (packets without an Ethernet header). Note that even after this patch, non-Ethernet interfaces are still not allowed to be added to bridges. Similarly, netlink interface for sending and receiving L3 packets to/from user space is not in place yet. Based on previous versions by Lorand Jakab and Simon Horman. Signed-off-by: Lorand Jakab Signed-off-by: Simon Horman Signed-off-by: Jiri Benc Acked-by: Pravin B Shelar Signed-off-by: David S. Miller --- net/openvswitch/datapath.c | 13 +---- net/openvswitch/flow.c | 106 ++++++++++++++++++++++++++++--------- net/openvswitch/vport.c | 19 +++++++ 3 files changed, 101 insertions(+), 37 deletions(-) diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index fa8760176b7d..1402f1be642d 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -560,7 +560,6 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) struct sw_flow *flow; struct sw_flow_actions *sf_acts; struct datapath *dp; - struct ethhdr *eth; struct vport *input_vport; u16 mru = 0; int len; @@ -581,17 +580,6 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) nla_memcpy(__skb_put(packet, len), a[OVS_PACKET_ATTR_PACKET], len); - skb_reset_mac_header(packet); - eth = eth_hdr(packet); - - /* Normally, setting the skb 'protocol' field would be handled by a - * call to eth_type_trans(), but it assumes there's a sending - * device, which we may not have. */ - if (eth_proto_is_802_3(eth->h_proto)) - packet->protocol = eth->h_proto; - else - packet->protocol = htons(ETH_P_802_2); - /* Set packet's mru */ if (a[OVS_PACKET_ATTR_MRU]) { mru = nla_get_u16(a[OVS_PACKET_ATTR_MRU]); @@ -618,6 +606,7 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) rcu_assign_pointer(flow->sf_acts, acts); packet->priority = flow->key.phy.priority; packet->mark = flow->key.phy.skb_mark; + packet->protocol = flow->key.eth.type; rcu_read_lock(); dp = get_dp_rcu(net, ovs_header->dp_ifindex); diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c index 96c8c4716603..08aa926cd5cf 100644 --- a/net/openvswitch/flow.c +++ b/net/openvswitch/flow.c @@ -334,14 +334,17 @@ static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh) return 1; } -static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key) +static void clear_vlan(struct sw_flow_key *key) { - int res; - key->eth.vlan.tci = 0; key->eth.vlan.tpid = 0; key->eth.cvlan.tci = 0; key->eth.cvlan.tpid = 0; +} + +static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key) +{ + int res; if (skb_vlan_tag_present(skb)) { key->eth.vlan.tci = htons(skb->vlan_tci); @@ -483,17 +486,20 @@ invalid: * * Returns 0 if successful, otherwise a negative errno value. * - * Initializes @skb header pointers as follows: + * Initializes @skb header fields as follows: * - * - skb->mac_header: the Ethernet header. + * - skb->mac_header: the L2 header. * - * - skb->network_header: just past the Ethernet header, or just past the - * VLAN header, to the first byte of the Ethernet payload. + * - skb->network_header: just past the L2 header, or just past the + * VLAN header, to the first byte of the L2 payload. * * - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6 * on output, then just past the IP header, if one is present and * of a correct length, otherwise the same as skb->network_header. * For other key->eth.type values it is left untouched. + * + * - skb->protocol: the type of the data starting at skb->network_header. + * Equals to key->eth.type. */ static int key_extract(struct sk_buff *skb, struct sw_flow_key *key) { @@ -505,28 +511,35 @@ static int key_extract(struct sk_buff *skb, struct sw_flow_key *key) skb_reset_mac_header(skb); - /* Link layer. We are guaranteed to have at least the 14 byte Ethernet - * header in the linear data area. - */ - eth = eth_hdr(skb); - ether_addr_copy(key->eth.src, eth->h_source); - ether_addr_copy(key->eth.dst, eth->h_dest); + /* Link layer. */ + clear_vlan(key); + if (key->mac_proto == MAC_PROTO_NONE) { + if (unlikely(eth_type_vlan(skb->protocol))) + return -EINVAL; - __skb_pull(skb, 2 * ETH_ALEN); - /* We are going to push all headers that we pull, so no need to - * update skb->csum here. - */ + skb_reset_network_header(skb); + } else { + eth = eth_hdr(skb); + ether_addr_copy(key->eth.src, eth->h_source); + ether_addr_copy(key->eth.dst, eth->h_dest); - if (unlikely(parse_vlan(skb, key))) - return -ENOMEM; + __skb_pull(skb, 2 * ETH_ALEN); + /* We are going to push all headers that we pull, so no need to + * update skb->csum here. + */ - key->eth.type = parse_ethertype(skb); - if (unlikely(key->eth.type == htons(0))) - return -ENOMEM; + if (unlikely(parse_vlan(skb, key))) + return -ENOMEM; + + skb->protocol = parse_ethertype(skb); + if (unlikely(skb->protocol == htons(0))) + return -ENOMEM; - skb_reset_network_header(skb); + skb_reset_network_header(skb); + __skb_push(skb, skb->data - skb_mac_header(skb)); + } skb_reset_mac_len(skb); - __skb_push(skb, skb->data - skb_mac_header(skb)); + key->eth.type = skb->protocol; /* Network layer. */ if (key->eth.type == htons(ETH_P_IP)) { @@ -721,9 +734,25 @@ int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key) return key_extract(skb, key); } +static int key_extract_mac_proto(struct sk_buff *skb) +{ + switch (skb->dev->type) { + case ARPHRD_ETHER: + return MAC_PROTO_ETHERNET; + case ARPHRD_NONE: + if (skb->protocol == htons(ETH_P_TEB)) + return MAC_PROTO_ETHERNET; + return MAC_PROTO_NONE; + } + WARN_ON_ONCE(1); + return -EINVAL; +} + int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info, struct sk_buff *skb, struct sw_flow_key *key) { + int res; + /* Extract metadata from packet. */ if (tun_info) { key->tun_proto = ip_tunnel_info_af(tun_info); @@ -751,7 +780,10 @@ int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info, key->phy.skb_mark = skb->mark; ovs_ct_fill_key(skb, key); key->ovs_flow_hash = 0; - key->mac_proto = MAC_PROTO_ETHERNET; + res = key_extract_mac_proto(skb); + if (res < 0) + return res; + key->mac_proto = res; key->recirc_id = 0; return key_extract(skb, key); @@ -768,5 +800,29 @@ int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr, if (err) return err; + if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) { + /* key_extract assumes that skb->protocol is set-up for + * layer 3 packets which is the case for other callers, + * in particular packets recieved from the network stack. + * Here the correct value can be set from the metadata + * extracted above. + */ + skb->protocol = key->eth.type; + } else { + struct ethhdr *eth; + + skb_reset_mac_header(skb); + eth = eth_hdr(skb); + + /* Normally, setting the skb 'protocol' field would be + * handled by a call to eth_type_trans(), but it assumes + * there's a sending device, which we may not have. + */ + if (eth_proto_is_802_3(eth->h_proto)) + skb->protocol = eth->h_proto; + else + skb->protocol = htons(ETH_P_802_2); + } + return key_extract(skb, key); } diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c index 898ed377b5cc..b6c8524032a0 100644 --- a/net/openvswitch/vport.c +++ b/net/openvswitch/vport.c @@ -485,6 +485,25 @@ void ovs_vport_send(struct vport *vport, struct sk_buff *skb, u8 mac_proto) { int mtu = vport->dev->mtu; + switch (vport->dev->type) { + case ARPHRD_NONE: + if (mac_proto == MAC_PROTO_ETHERNET) { + skb_reset_network_header(skb); + skb_reset_mac_len(skb); + skb->protocol = htons(ETH_P_TEB); + } else if (mac_proto != MAC_PROTO_NONE) { + WARN_ON_ONCE(1); + goto drop; + } + break; + case ARPHRD_ETHER: + if (mac_proto != MAC_PROTO_ETHERNET) + goto drop; + break; + default: + goto drop; + } + if (unlikely(packet_length(skb, vport->dev) > mtu && !skb_is_gso(skb))) { net_warn_ratelimited("%s: dropped over-mtu packet: %d > %d\n", -- 2.20.1