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