include/linux/pim.h

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