blob: 82de336b81550af6a64fff632037acec7e145f2a [file] [log] [blame]
* Linux NET3: Internet Group Management Protocol [IGMP]
* Authors:
* Alan Cox <>
* Extended to talk the BSD extended IGMP protocol of mrouted 3.6
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
#ifndef _LINUX_IGMP_H
#define _LINUX_IGMP_H
#include <linux/types.h>
#include <asm/byteorder.h>
* IGMP protocol structures
* Header in on cable format
struct igmphdr {
__u8 type;
__u8 code; /* For newer IGMP */
__sum16 csum;
__be32 group;
/* V3 group record types [grec_type] */
struct igmpv3_grec {
__u8 grec_type;
__u8 grec_auxwords;
__be16 grec_nsrcs;
__be32 grec_mca;
__be32 grec_src[0];
struct igmpv3_report {
__u8 type;
__u8 resv1;
__be16 csum;
__be16 resv2;
__be16 ngrec;
struct igmpv3_grec grec[0];
struct igmpv3_query {
__u8 type;
__u8 code;
__be16 csum;
__be32 group;
__u8 qrv:3,
#elif defined(__BIG_ENDIAN_BITFIELD)
__u8 resv:4,
#error "Please fix <asm/byteorder.h>"
__u8 qqic;
__be16 nsrcs;
__be32 srcs[0];
#define IGMP_HOST_MEMBERSHIP_QUERY 0x11 /* From RFC1112 */
#define IGMP_HOST_MEMBERSHIP_REPORT 0x12 /* Ditto */
#define IGMP_DVMRP 0x13 /* DVMRP routing */
#define IGMP_PIM 0x14 /* PIM routing */
#define IGMP_TRACE 0x15
#define IGMPV2_HOST_MEMBERSHIP_REPORT 0x16 /* V2 version of 0x12 */
#define IGMPV3_HOST_MEMBERSHIP_REPORT 0x22 /* V3 version of 0x12 */
#define IGMP_MTRACE_RESP 0x1e
#define IGMP_MTRACE 0x1f
* Use the BSD names for these for compatibility
#define IGMP_IDLE_MEMBER 0x02
#define IGMP_LAZY_MEMBER 0x03
#define IGMP_MINLEN 8
#define IGMP_MAX_HOST_REPORT_DELAY 10 /* max delay for response to */
/* query (in seconds) */
#define IGMP_TIMER_SCALE 10 /* denotes that the igmphdr->timer field */
/* specifies time in 10th of seconds */
#define IGMP_AGE_THRESHOLD 400 /* If this host don't hear any IGMP V1 */
/* message in this period of time, */
/* revert to IGMP v2 router. */
#define IGMP_ALL_HOSTS htonl(0xE0000001L)
#define IGMP_ALL_ROUTER htonl(0xE0000002L)
#define IGMPV3_ALL_MCR htonl(0xE0000016L)
#define IGMP_LOCAL_GROUP htonl(0xE0000000L)
* struct for keeping the multicast list in
#ifdef __KERNEL__
#include <linux/skbuff.h>
#include <linux/timer.h>
#include <linux/in.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);
extern int sysctl_igmp_max_memberships;
extern int sysctl_igmp_max_msf;
struct ip_sf_socklist {
unsigned int sl_max;
unsigned int sl_count;
struct rcu_head rcu;
__be32 sl_addr[0];
#define IP_SFLSIZE(count) (sizeof(struct ip_sf_socklist) + \
(count) * sizeof(__be32))
#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;
__be32 sf_inaddr;
unsigned long sf_count[2]; /* include/exclude counts */
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 timer_list timer;
int users;
atomic_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)
extern int ip_check_mc_rcu(struct in_device *dev, __be32 mc_addr, __be32 src_addr, u16 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_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 group_filter __user *optval, int __user *optlen);
extern int ip_mc_sf_allow(struct sock *sk, __be32 local, __be32 rmt, int dif);
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);
extern void ip_mc_inc_group(struct in_device *in_dev, __be32 addr);
extern void ip_mc_rejoin_groups(struct in_device *in_dev);