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
igmp_hdr(const struct sk_buff * skb)20 static inline struct igmphdr *igmp_hdr(const struct sk_buff *skb)
21 {
22 return (struct igmphdr *)skb_transport_header(skb);
23 }
24
25 static inline struct igmpv3_report *
igmpv3_report_hdr(const struct sk_buff * skb)26 igmpv3_report_hdr(const struct sk_buff *skb)
27 {
28 return (struct igmpv3_report *)skb_transport_header(skb);
29 }
30
31 static inline struct igmpv3_query *
igmpv3_query_hdr(const struct sk_buff * skb)32 igmpv3_query_hdr(const struct sk_buff *skb)
33 {
34 return (struct igmpv3_query *)skb_transport_header(skb);
35 }
36
37 struct ip_sf_socklist {
38 unsigned int sl_max;
39 unsigned int sl_count;
40 struct rcu_head rcu;
41 __be32 sl_addr[];
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
53 struct 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
61 struct ip_sf_list {
62 struct ip_sf_list *sf_next;
63 unsigned long sf_count[2]; /* include/exclude counts */
64 __be32 sf_inaddr;
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
70 struct 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
ip_mc_may_pull(struct sk_buff * skb,unsigned int len)105 static 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
113 extern int ip_check_mc_rcu(struct in_device *dev, __be32 mc_addr, __be32 src_addr, u8 proto);
114 extern int igmp_rcv(struct sk_buff *);
115 extern int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr);
116 extern int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
117 unsigned int mode);
118 extern int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr);
119 extern void ip_mc_drop_socket(struct sock *sk);
120 extern int ip_mc_source(int add, int omode, struct sock *sk,
121 struct ip_mreq_source *mreqs, int ifindex);
122 extern int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf,int ifindex);
123 extern int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
124 struct ip_msfilter __user *optval, int __user *optlen);
125 extern int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
126 struct sockaddr_storage __user *p);
127 extern int ip_mc_sf_allow(struct sock *sk, __be32 local, __be32 rmt,
128 int dif, int sdif);
129 extern void ip_mc_init_dev(struct in_device *);
130 extern void ip_mc_destroy_dev(struct in_device *);
131 extern void ip_mc_up(struct in_device *);
132 extern void ip_mc_down(struct in_device *);
133 extern void ip_mc_unmap(struct in_device *);
134 extern void ip_mc_remap(struct in_device *);
135 extern void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp);
ip_mc_dec_group(struct in_device * in_dev,__be32 addr)136 static 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 }
140 extern void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
141 gfp_t gfp);
142 extern void ip_mc_inc_group(struct in_device *in_dev, __be32 addr);
143 int ip_mc_check_igmp(struct sk_buff *skb);
144
145 #endif
146
