LXR linux/include/linux/igmp.h

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 *      Linux NET3:     Internet Group Management Protocol  [IGMP]
   4 *
   5 *      Authors:
   6 *              Alan Cox <alan@lxorguk.ukuu.org.uk>
   7 *
   8 *      Extended to talk the BSD extended IGMP protocol of mrouted 3.6
   9 */
  10#ifndef _LINUX_IGMP_H
  11#define _LINUX_IGMP_H
  12
  13#include <linux/skbuff.h>
  14#include <linux/timer.h>
  15#include <linux/in.h>
  16#include <linux/ip.h>
  17#include <linux/refcount.h>
  18#include <uapi/linux/igmp.h>
  19
  20static inline struct igmphdr *igmp_hdr(const struct sk_buff *skb)
  21{
  22        return (struct igmphdr *)skb_transport_header(skb);
  23}
  24
  25static inline struct igmpv3_report *
  26                        igmpv3_report_hdr(const struct sk_buff *skb)
  27{
  28        return (struct igmpv3_report *)skb_transport_header(skb);
  29}
  30
  31static inline struct igmpv3_query *
  32                        igmpv3_query_hdr(const struct sk_buff *skb)
  33{
  34        return (struct igmpv3_query *)skb_transport_header(skb);
  35}
  36
  37struct ip_sf_socklist {
  38        unsigned int            sl_max;
  39        unsigned int            sl_count;
  40        struct rcu_head         rcu;
  41        __be32                  sl_addr[0];
  42};
  43
  44#define IP_SFLSIZE(count)       (sizeof(struct ip_sf_socklist) + \
  45        (count) * sizeof(__be32))
  46
  47#define IP_SFBLOCK      10      /* allocate this many at once */
  48
  49/* ip_mc_socklist is real list now. Speed is not argument;
  50   this list never used in fast path code
  51 */
  52
  53struct ip_mc_socklist {
  54        struct ip_mc_socklist __rcu *next_rcu;
  55        struct ip_mreqn         multi;
  56        unsigned int            sfmode;         /* MCAST_{INCLUDE,EXCLUDE} */
  57        struct ip_sf_socklist __rcu     *sflist;
  58        struct rcu_head         rcu;
  59};
  60
  61struct ip_sf_list {
  62        struct ip_sf_list       *sf_next;
  63        __be32                  sf_inaddr;
  64        unsigned long           sf_count[2];    /* include/exclude counts */
  65        unsigned char           sf_gsresp;      /* include in g & s response? */
  66        unsigned char           sf_oldin;       /* change state */
  67        unsigned char           sf_crcount;     /* retrans. left to send */
  68};
  69
  70struct ip_mc_list {
  71        struct in_device        *interface;
  72        __be32                  multiaddr;
  73        unsigned int            sfmode;
  74        struct ip_sf_list       *sources;
  75        struct ip_sf_list       *tomb;
  76        unsigned long           sfcount[2];
  77        union {
  78                struct ip_mc_list *next;
  79                struct ip_mc_list __rcu *next_rcu;
  80        };
  81        struct ip_mc_list __rcu *next_hash;
  82        struct timer_list       timer;
  83        int                     users;
  84        refcount_t              refcnt;
  85        spinlock_t              lock;
  86        char                    tm_running;
  87        char                    reporter;
  88        char                    unsolicit_count;
  89        char                    loaded;
  90        unsigned char           gsquery;        /* check source marks? */
  91        unsigned char           crcount;
  92        struct rcu_head         rcu;
  93};
  94
  95/* V3 exponential field decoding */
  96#define IGMPV3_MASK(value, nb) ((nb)>=32 ? (value) : ((1<<(nb))-1) & (value))
  97#define IGMPV3_EXP(thresh, nbmant, nbexp, value) \
  98        ((value) < (thresh) ? (value) : \
  99        ((IGMPV3_MASK(value, nbmant) | (1<<(nbmant))) << \
 100         (IGMPV3_MASK((value) >> (nbmant), nbexp) + (nbexp))))
 101
 102#define IGMPV3_QQIC(value) IGMPV3_EXP(0x80, 4, 3, value)
 103#define IGMPV3_MRC(value) IGMPV3_EXP(0x80, 4, 3, value)
 104
 105static inline int ip_mc_may_pull(struct sk_buff *skb, unsigned int len)
 106{
 107        if (skb_transport_offset(skb) + ip_transport_len(skb) < len)
 108                return 0;
 109
 110        return pskb_may_pull(skb, len);
 111}
 112
 113extern int ip_check_mc_rcu(struct in_device *dev, __be32 mc_addr, __be32 src_addr, u8 proto);
 114extern int igmp_rcv(struct sk_buff *);
 115extern int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr);
 116extern int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
 117                                unsigned int mode);
 118extern int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr);
 119extern void ip_mc_drop_socket(struct sock *sk);
 120extern int ip_mc_source(int add, int omode, struct sock *sk,
 121                struct ip_mreq_source *mreqs, int ifindex);
 122extern int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf,int ifindex);
 123extern int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
 124                struct ip_msfilter __user *optval, int __user *optlen);
 125extern int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
 126                struct group_filter __user *optval, int __user *optlen);
 127extern int ip_mc_sf_allow(struct sock *sk, __be32 local, __be32 rmt,
 128                          int dif, int sdif);
 129extern void ip_mc_init_dev(struct in_device *);
 130extern void ip_mc_destroy_dev(struct in_device *);
 131extern void ip_mc_up(struct in_device *);
 132extern void ip_mc_down(struct in_device *);
 133extern void ip_mc_unmap(struct in_device *);
 134extern void ip_mc_remap(struct in_device *);
 135extern void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp);
 136static inline void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
 137{
 138        return __ip_mc_dec_group(in_dev, addr, GFP_KERNEL);
 139}
 140extern void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
 141                              gfp_t gfp);
 142extern void ip_mc_inc_group(struct in_device *in_dev, __be32 addr);
 143int ip_mc_check_igmp(struct sk_buff *skb);
 144
 145#endif
 146