PUNT socket: External control plane processes connected via UNIX domain sockets.

An external (to VPP) process can register (over the VPP binary API) to
receive control plane packets over a UNIX domain socket. The packets are
prepended with a packet descriptor containing meta-data (if_index of
interface, etc).

Currently only UDP is supported.

The socket supports sending of packets/frames as well.
The sent packet is prepended with a descriptor, telling VPP to
route the packet (via ip4-lookup, ip6-lookup) or as an pre-formed
Ethernet frame that is sent directly to interface-output.

The intended use case for this is for an external DHCP client or
a RIP implementation.

New configuration option:

punt { socket <socket path> }

To register use the punt_socket API message.

TODO:
  - Add support for pre-routing. I.e send L3 packet to given
    TX interface, but do ARP/ND (ip[46]-rewrite)
  - Add test scripts
  - Support for abstract names (starting with \0)
  - Add rate limiting (COP)
  - Support for other protocols, e.g. IPv6 ND

Change-Id: I4a0afc8020deebb3d9d74686dde694ee5bcb8d0f
Signed-off-by: Ole Troan <ot@cisco.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/src/vpp/api/vpe.api b/src/vpp/api/vpe.api
index ec5ffbe9..0dee1533 100644
--- a/src/vpp/api/vpe.api
+++ b/src/vpp/api/vpe.api
@@ -991,6 +991,39 @@ autoreply define punt {
     u16 l4_port;
 };
 
+/** \brief Punt traffic to the host via socket
+    @param client_index - opaque cookie to identify the sender
+    @param context - sender context, to match reply w/ request
+    @param header_version - expected meta data header version (currently 1)
+    @param is_ip4 - L3 protocol 1 - IPv4, 0 - IPv6
+    @param l4_protocol - L4 protocol to be punted, only UDP (0x11) is supported
+    @param l4_port - TCP/UDP port to be punted
+*/
+define punt_socket_register {
+    u32 client_index;
+    u32 context;
+    u32 header_version;
+    u8 is_ip4;
+    u8 l4_protocol;
+    u16 l4_port;
+    u8 pathname[64];
+};
+
+define punt_socket_register_reply
+{
+  u32 context;
+  i32 retval;
+  u8 pathname[64];
+};
+
+autoreply define punt_socket_deregister {
+    u32 client_index;
+    u32 context;
+    u8 is_ip4;
+    u8 l4_protocol;
+    u16 l4_port;
+};
+
 /** \brief Feature path enable/disable request
     @param client_index - opaque cookie to identify the sender
     @param context - sender context, to match reply w/ request