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