blob: 93c262ecbdc92732f902ab0ceb1ceffc63cea1dc [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0-or-later */
* Linux NET3: Internet Group Management Protocol [IGMP]
* Authors:
* Alan Cox <>
* Extended to talk the BSD extended IGMP protocol of mrouted 3.6
#ifndef _LINUX_IGMP_H
#define _LINUX_IGMP_H
#include <linux/skbuff.h>
#include <linux/timer.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/refcount.h>
#include <uapi/linux/igmp.h>
static inline struct igmphdr *igmp_hdr(const struct sk_buff *skb)
return (struct igmphdr *)skb_transport_header(skb);
static inline struct igmpv3_report *
igmpv3_report_hdr(const struct sk_buff *skb)
return (struct igmpv3_report *)skb_transport_header(skb);
static inline struct igmpv3_query *
igmpv3_query_hdr(const struct sk_buff *skb)
return (struct igmpv3_query *)skb_transport_header(skb);
struct ip_sf_socklist {
unsigned int sl_max;
unsigned int sl_count;
struct rcu_head rcu;
__be32 sl_addr[];
#define IP_SFBLOCK 10 /* allocate this many at once */
/* ip_mc_socklist is real list now. Speed is not argument;
this list never used in fast path code
struct ip_mc_socklist {
struct ip_mc_socklist __rcu *next_rcu;
struct ip_mreqn multi;
unsigned int sfmode; /* MCAST_{INCLUDE,EXCLUDE} */
struct ip_sf_socklist __rcu *sflist;
struct rcu_head rcu;
struct ip_sf_list {
struct ip_sf_list *sf_next;
unsigned long sf_count[2]; /* include/exclude counts */
__be32 sf_inaddr;
unsigned char sf_gsresp; /* include in g & s response? */
unsigned char sf_oldin; /* change state */
unsigned char sf_crcount; /* retrans. left to send */
struct ip_mc_list {
struct in_device *interface;
__be32 multiaddr;
unsigned int sfmode;
struct ip_sf_list *sources;
struct ip_sf_list *tomb;
unsigned long sfcount[2];
union {
struct ip_mc_list *next;
struct ip_mc_list __rcu *next_rcu;
struct ip_mc_list __rcu *next_hash;
struct timer_list timer;
int users;
refcount_t refcnt;
spinlock_t lock;
char tm_running;
char reporter;
char unsolicit_count;
char loaded;
unsigned char gsquery; /* check source marks? */
unsigned char crcount;
struct rcu_head rcu;
/* V3 exponential field decoding */
#define IGMPV3_MASK(value, nb) ((nb)>=32 ? (value) : ((1<<(nb))-1) & (value))
#define IGMPV3_EXP(thresh, nbmant, nbexp, value) \
((value) < (thresh) ? (value) : \
((IGMPV3_MASK(value, nbmant) | (1<<(nbmant))) << \
(IGMPV3_MASK((value) >> (nbmant), nbexp) + (nbexp))))
#define IGMPV3_QQIC(value) IGMPV3_EXP(0x80, 4, 3, value)
#define IGMPV3_MRC(value) IGMPV3_EXP(0x80, 4, 3, value)
static inline int ip_mc_may_pull(struct sk_buff *skb, unsigned int len)
if (skb_transport_offset(skb) + ip_transport_len(skb) < len)
return 0;
return pskb_may_pull(skb, len);
extern int ip_check_mc_rcu(struct in_device *dev, __be32 mc_addr, __be32 src_addr, u8 proto);
extern int igmp_rcv(struct sk_buff *);
extern int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr);
extern int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
unsigned int mode);
extern int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr);
extern void ip_mc_drop_socket(struct sock *sk);
extern int ip_mc_source(int add, int omode, struct sock *sk,
struct ip_mreq_source *mreqs, int ifindex);
extern int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf,int ifindex);
extern int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
struct ip_msfilter __user *optval, int __user *optlen);
extern int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
struct sockaddr_storage __user *p);
extern int ip_mc_sf_allow(struct sock *sk, __be32 local, __be32 rmt,
int dif, int sdif);
extern void ip_mc_init_dev(struct in_device *);
extern void ip_mc_destroy_dev(struct in_device *);
extern void ip_mc_up(struct in_device *);
extern void ip_mc_down(struct in_device *);
extern void ip_mc_unmap(struct in_device *);
extern void ip_mc_remap(struct in_device *);
extern void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp);
static inline void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
return __ip_mc_dec_group(in_dev, addr, GFP_KERNEL);
extern void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
gfp_t gfp);
extern void ip_mc_inc_group(struct in_device *in_dev, __be32 addr);
int ip_mc_check_igmp(struct sk_buff *skb);