Re: [PATCH net-next 4/4] net: Add Open vSwitch kernel components.

On 11/19/2011 3:06 PM, Jesse Gross wrote:

On Fri, Nov 18, 2011 at 9:30 PM, John Fastabend
[off-list ref] wrote:

quoted

On 11/18/2011 3:12 PM, Jesse Gross wrote:

quoted

+ */
+enum ovs_frag_type {
+       OVS_FRAG_TYPE_NONE,
+       OVS_FRAG_TYPE_FIRST,
+       OVS_FRAG_TYPE_LATER,
+       __OVS_FRAG_TYPE_MAX
+};
+
+#define OVS_FRAG_TYPE_MAX (__OVS_FRAG_TYPE_MAX - 1)
+
+struct ovs_key_ethernet {
+       __u8     eth_src[6];
+       __u8     eth_dst[6];
+};
+
+struct ovs_key_ipv4 {
+       __be32 ipv4_src;
+       __be32 ipv4_dst;
+       __u8   ipv4_proto;
+       __u8   ipv4_tos;
+       __u8   ipv4_ttl;
+       __u8   ipv4_frag;       /* One of OVS_FRAG_TYPE_*. */
+};
+
+struct ovs_key_ipv6 {
+       __be32 ipv6_src[4];
+       __be32 ipv6_dst[4];
+       __be32 ipv6_label;      /* 20-bits in least-significant bits. */
+       __u8   ipv6_proto;
+       __u8   ipv6_tclass;
+       __u8   ipv6_hlimit;
+       __u8   ipv6_frag;       /* One of OVS_FRAG_TYPE_*. */
+};
+
+struct ovs_key_tcp {
+       __be16 tcp_src;
+       __be16 tcp_dst;
+};
+
+struct ovs_key_udp {
+       __be16 udp_src;
+       __be16 udp_dst;
+};
+
+struct ovs_key_icmp {
+       __u8 icmp_type;
+       __u8 icmp_code;
+};
+
+struct ovs_key_icmpv6 {
+       __u8 icmpv6_type;
+       __u8 icmpv6_code;
+};
+
+struct ovs_key_arp {
+       __be32 arp_sip;
+       __be32 arp_tip;
+       __be16 arp_op;
+       __u8   arp_sha[6];
+       __u8   arp_tha[6];
+};
+
+struct ovs_key_nd {
+       __u32 nd_target[4];
+       __u8  nd_sll[6];
+       __u8  nd_tll[6];
+};
+

We already have defines for many of these headers
struct arphdr {
       __be16          ar_hrd;         /* format of hardware address   */
       __be16          ar_pro;         /* format of protocol address   */
       unsigned char   ar_hln;         /* length of hardware address   */
       unsigned char   ar_pln;         /* length of protocol address   */
       __be16          ar_op;          /* ARP opcode (command)         */

#if 0
        /*
         *      Ethernet looks like this : This bit is variable sized however...
         */
       unsigned char           ar_sha[ETH_ALEN];       /* sender hardware address      */
       unsigned char           ar_sip[4];              /* sender IP address            */
       unsigned char           ar_tha[ETH_ALEN];       /* target hardware address      */
       unsigned char           ar_tip[4];              /* target IP address            */
#endif

};

Do we have to redefine them here?

These aren't packet format definitions, they're keys for describing a
flow to userspace.  For example, they don't contain checksums or
lengths because those vary on a per-packet basis.

OK thanks for explaining. I get it now, the other responses seem reasonable
as well.

Thanks,
John.