LXR linux/include/linux/pim.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __LINUX_PIM_H
   3#define __LINUX_PIM_H
   4
   5#include <linux/skbuff.h>
   6#include <asm/byteorder.h>
   7
   8/* Message types - V1 */
   9#define PIM_V1_VERSION          cpu_to_be32(0x10000000)
  10#define PIM_V1_REGISTER         1
  11
  12/* Message types - V2 */
  13#define PIM_VERSION             2
  14
  15/* RFC7761, sec 4.9:
  16 *  Type
  17 *        Types for specific PIM messages.  PIM Types are:
  18 *
  19 *  Message Type                          Destination
  20 *  ---------------------------------------------------------------------
  21 *  0 = Hello                             Multicast to ALL-PIM-ROUTERS
  22 *  1 = Register                          Unicast to RP
  23 *  2 = Register-Stop                     Unicast to source of Register
  24 *                                        packet
  25 *  3 = Join/Prune                        Multicast to ALL-PIM-ROUTERS
  26 *  4 = Bootstrap                         Multicast to ALL-PIM-ROUTERS
  27 *  5 = Assert                            Multicast to ALL-PIM-ROUTERS
  28 *  6 = Graft (used in PIM-DM only)       Unicast to RPF'(S)
  29 *  7 = Graft-Ack (used in PIM-DM only)   Unicast to source of Graft
  30 *                                        packet
  31 *  8 = Candidate-RP-Advertisement        Unicast to Domain's BSR
  32 */
  33enum {
  34        PIM_TYPE_HELLO,
  35        PIM_TYPE_REGISTER,
  36        PIM_TYPE_REGISTER_STOP,
  37        PIM_TYPE_JOIN_PRUNE,
  38        PIM_TYPE_BOOTSTRAP,
  39        PIM_TYPE_ASSERT,
  40        PIM_TYPE_GRAFT,
  41        PIM_TYPE_GRAFT_ACK,
  42        PIM_TYPE_CANDIDATE_RP_ADV
  43};
  44
  45#define PIM_NULL_REGISTER       cpu_to_be32(0x40000000)
  46
  47/* RFC7761, sec 4.9:
  48 * The PIM header common to all PIM messages is:
  49 *   0                   1                   2                   3
  50 *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  51 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  52 *  |PIM Ver| Type  |   Reserved    |           Checksum            |
  53 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  54 */
  55struct pimhdr {
  56        __u8    type;
  57        __u8    reserved;
  58        __be16  csum;
  59};
  60
  61/* PIMv2 register message header layout (ietf-draft-idmr-pimvsm-v2-00.ps */
  62struct pimreghdr {
  63        __u8    type;
  64        __u8    reserved;
  65        __be16  csum;
  66        __be32  flags;
  67};
  68
  69int pim_rcv_v1(struct sk_buff *skb);
  70
  71static inline bool ipmr_pimsm_enabled(void)
  72{
  73        return IS_BUILTIN(CONFIG_IP_PIMSM_V1) || IS_BUILTIN(CONFIG_IP_PIMSM_V2);
  74}
  75
  76static inline struct pimhdr *pim_hdr(const struct sk_buff *skb)
  77{
  78        return (struct pimhdr *)skb_transport_header(skb);
  79}
  80
  81static inline u8 pim_hdr_version(const struct pimhdr *pimhdr)
  82{
  83        return pimhdr->type >> 4;
  84}
  85
  86static inline u8 pim_hdr_type(const struct pimhdr *pimhdr)
  87{
  88        return pimhdr->type & 0xf;
  89}
  90
  91/* check if the address is 224.0.0.13, RFC7761 sec 4.3.1 */
  92static inline bool pim_ipv4_all_pim_routers(__be32 addr)
  93{
  94        return addr == htonl(0xE000000D);
  95}
  96#endif
  97