buffer.h

Go to the documentation of this file.

/*
 * Copyright (c) 2015 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * vnet/buffer.h: vnet buffer flags
 *
 * Copyright (c) 2008 Eliot Dresselhaus
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef included_vnet_buffer_h
#define included_vnet_buffer_h

#include <vlib/vlib.h>

/* VLIB buffer flags for ip4/ip6 packets.  Set by input interfaces for ip4/ip6
   tcp/udp packets with hardware computed checksums. */
#define LOG2_IP_BUFFER_L4_CHECKSUM_COMPUTED LOG2_VLIB_BUFFER_FLAG_USER(1)
#define LOG2_IP_BUFFER_L4_CHECKSUM_CORRECT  LOG2_VLIB_BUFFER_FLAG_USER(2)
#define IP_BUFFER_L4_CHECKSUM_COMPUTED (1 << LOG2_IP_BUFFER_L4_CHECKSUM_COMPUTED)
#define IP_BUFFER_L4_CHECKSUM_CORRECT  (1 << LOG2_IP_BUFFER_L4_CHECKSUM_CORRECT)

/* VLAN header flags.
 * These bits are zeroed in vlib_buffer_init_for_free_list()
 * meaning wherever the buffer comes from they have a reasonable
 * value (eg, if ip4/ip6 generates the packet.)
 */
#define LOG2_ETH_BUFFER_VLAN_2_DEEP LOG2_VLIB_BUFFER_FLAG_USER(3)
#define LOG2_ETH_BUFFER_VLAN_1_DEEP LOG2_VLIB_BUFFER_FLAG_USER(4)
#define ETH_BUFFER_VLAN_2_DEEP (1 << LOG2_ETH_BUFFER_VLAN_2_DEEP)
#define ETH_BUFFER_VLAN_1_DEEP (1 << LOG2_ETH_BUFFER_VLAN_1_DEEP)
#define ETH_BUFFER_VLAN_BITS (ETH_BUFFER_VLAN_1_DEEP | \
                              ETH_BUFFER_VLAN_2_DEEP)

#define LOG2_BUFFER_HANDOFF_NEXT_VALID LOG2_VLIB_BUFFER_FLAG_USER(6)
#define BUFFER_HANDOFF_NEXT_VALID (1 << LOG2_BUFFER_HANDOFF_NEXT_VALID)

#define LOG2_VNET_BUFFER_LOCALLY_ORIGINATED LOG2_VLIB_BUFFER_FLAG_USER(7)
#define VNET_BUFFER_LOCALLY_ORIGINATED (1 << LOG2_VNET_BUFFER_LOCALLY_ORIGINATED)

#define LOG2_VNET_BUFFER_SPAN_CLONE LOG2_VLIB_BUFFER_FLAG_USER(8)
#define VNET_BUFFER_SPAN_CLONE (1 << LOG2_VNET_BUFFER_SPAN_CLONE)

#define foreach_buffer_opaque_union_subtype     \
_(ethernet)                                     \
_(ip)                                           \
_(swt)                                          \
_(l2)                                           \
_(l2t)                                          \
_(gre)                                          \
_(l2_classify)                                  \
_(handoff)                                      \
_(policer)                                      \
_(ipsec)                                        \
_(map)                                          \
_(map_t)                                        \
_(ip_frag)                                      \
_(tcp)

/*
 * vnet stack buffer opaque array overlay structure.
 * The vnet_buffer_opaque_t *must* be the same size as the
 * vlib_buffer_t "opaque" structure member, 32 bytes.
 *
 * When adding a union type, please add a stanza to
 * foreach_buffer_opaque_union_subtype (directly above).
 * Code in vnet_interface_init(...) verifies the size
 * of the union, and will announce any deviations in an
 * impossible-to-miss manner.
 */
typedef struct
{
  u32 sw_if_index[VLIB_N_RX_TX];

  union
  {
    /* Ethernet. */
    struct
    {
      /* Saved value of current header by ethernet-input. */
      i32 start_of_ethernet_header;
    } ethernet;

    /* IP4/6 buffer opaque. */
    struct
    {
      /* Adjacency from destination IP address lookup [VLIB_TX].
         Adjacency from source IP address lookup [VLIB_RX].
         This gets set to ~0 until source lookup is performed. */
      u32 adj_index[VLIB_N_RX_TX];

      union
      {
        struct
        {
          /* Flow hash value for this packet computed from IP src/dst address
             protocol and ports. */
          u32 flow_hash;

          /* next protocol */
          u32 save_protocol;

          /* Rewrite length */
          u32 save_rewrite_length;

          /* MFIB RPF ID */
          u32 rpf_id;
        };

        /* ICMP */
        struct
        {
          u8 type;
          u8 code;
          u32 data;
        } icmp;

        /* IP header offset from vlib_buffer.data - saved by ip*_local nodes */
        i32 start_of_ip_header;
      };

    } ip;

    /*
     * MPLS:
     * data copied from the MPLS header that was popped from the packet
     * during the look-up.
     */
    struct
    {
      u8 ttl;
      u8 exp;
      u8 first;
    } mpls;

    /* ip4-in-ip6 softwire termination, only valid there */
    struct
    {
      u8 swt_disable;
      u32 mapping_index;
    } swt;

    /* l2 bridging path, only valid there */
    struct opaque_l2
    {
      u32 feature_bitmap;
      u16 bd_index;             /* bridge-domain index */
      u8 l2_len;                /* ethernet header length */
      u8 shg;                   /* split-horizon group */
      u16 l2fib_sn;             /* l2fib bd/int seq_num */
    } l2;

    /* l2tpv3 softwire encap, only valid there */
    struct
    {
      u32 pad[4];               /* do not overlay w/ ip.adj_index[0,1] */
      u8 next_index;
      u32 session_index;
    } l2t;

    struct
    {
      u32 src, dst;
    } gre;

    /* L2 classify */
    struct
    {
      struct opaque_l2 pad;
      union
      {
        u32 table_index;
        u32 opaque_index;
      };
      u64 hash;
    } l2_classify;

    /* IO - worker thread handoff */
    struct
    {
      u32 next_index;
    } handoff;

    /* vnet policer */
    struct
    {
      u32 pad[8 - VLIB_N_RX_TX - 1];    /* to end of opaque */
      u32 index;
    } policer;

    /* interface output features */
    struct
    {
      u32 flags;
      u32 sad_index;
    } ipsec;

    /* MAP */
    struct
    {
      u16 mtu;
    } map;

    /* MAP-T */
    struct
    {
      u32 map_domain_index;
      struct
      {
        u32 saddr, daddr;
        u16 frag_offset;        //Fragmentation header offset
        u16 l4_offset;          //L4 header overall offset
        u8 l4_protocol;         //The final protocol number
      } v6;                     //Used by ip6_map_t only
      u16 checksum_offset;      //L4 checksum overall offset
      u16 mtu;                  //Exit MTU
    } map_t;

    /* IP Fragmentation */
    struct
    {
      u16 header_offset;
      u16 mtu;
      u8 next_index;
      u8 flags;                 //See ip_frag.h
    } ip_frag;

    /* COP - configurable junk filter(s) */
    struct
    {
      /* Current configuration index. */
      u32 current_config_index;
    } cop;

    /* LISP */
    struct
    {
      /* overlay address family */
      u16 overlay_afi;
    } lisp;

    /* Driver rx feature */
    struct
    {
      u32 saved_next_index;             /**< saved by drivers for short-cut */
      u16 buffer_advance;
    } device_input_feat;

    /* TCP */
    struct
    {
      u32 connection_index;
      u32 seq_number;
      u32 seq_end;
      u32 ack_number;
      u16 hdr_offset;           /**< offset relative to ip hdr */
      u16 data_offset;          /**< offset relative to ip hdr */
      u16 data_len;             /**< data len */
      u8 flags;
    } tcp;

    u32 unused[6];
  };
} vnet_buffer_opaque_t;

/*
 * The opaque field of the vlib_buffer_t is intepreted as a
 * vnet_buffer_opaque_t. Hence it should be big enough to accommodate one.
 */
STATIC_ASSERT (sizeof (vnet_buffer_opaque_t) <=
               STRUCT_SIZE_OF (vlib_buffer_t, opaque),
               "VNET buffer meta-data too large for vlib_buffer");

#define vnet_buffer(b) ((vnet_buffer_opaque_t *) (b)->opaque)

/* Full cache line (64 bytes) of additional space */
typedef struct
{
  union
  {
  };
} vnet_buffer_opaque2_t;



#endif /* included_vnet_buffer_h */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */