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 21 static inline struct igmphdr *igmp_hdr(const struct sk_buff *skb) 22 { 23 return (struct igmphdr *)skb_transport_header(skb); 24 } 25 26 static 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 32 static 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 38 struct ip_sf_socklist { 39 unsigned int sl_max; 40 unsigned int sl_count; 41 struct rcu_head rcu; 42 __be32 sl_addr[]; 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 51 struct 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 59 struct 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 68 struct 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) 102 103 static 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 } 110 111 extern int ip_check_mc_rcu(struct in_device *dev, __be32 mc_addr, __be32 src_addr, u8 proto); 112 extern int igmp_rcv(struct sk_buff *); 113 extern int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr); 114 extern int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr, 115 unsigned int mode); 116 extern int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr); 117 extern void ip_mc_drop_socket(struct sock *sk); 118 extern int ip_mc_source(int add, int omode, struct sock *sk, 119 struct ip_mreq_source *mreqs, int ifindex); 120 extern int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf,int ifindex); 121 extern int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 122 sockptr_t optval, sockptr_t optlen); 123 extern int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, 124 sockptr_t optval, size_t offset); 125 extern int ip_mc_sf_allow(struct sock *sk, __be32 local, __be32 rmt, 126 int dif, int sdif); 127 extern void ip_mc_init_dev(struct in_device *); 128 extern void ip_mc_destroy_dev(struct in_device *); 129 extern void ip_mc_up(struct in_device *); 130 extern void ip_mc_down(struct in_device *); 131 extern void ip_mc_unmap(struct in_device *); 132 extern void ip_mc_remap(struct in_device *); 133 extern void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp); 134 static 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 } 138 extern void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr, 139 gfp_t gfp); 140 extern void ip_mc_inc_group(struct in_device *in_dev, __be32 addr); 141 int ip_mc_check_igmp(struct sk_buff *skb); 142 143 #endif 144