1 #ifndef __LINUX_NETLINK_H 2 #define __LINUX_NETLINK_H 3 4 5 #include <linux/capability.h> 6 #include <linux/skbuff.h> 7 #include <linux/export.h> 8 #include <net/scm.h> 9 #include <uapi/linux/netlink.h> 10 11 struct net; 12 13 static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb) 14 { 15 return (struct nlmsghdr *)skb->data; 16 } 17 18 struct netlink_skb_parms { 19 struct scm_creds creds; /* Skb credentials */ 20 __u32 portid; 21 __u32 dst_group; 22 struct sock *ssk; 23 }; 24 25 #define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb)) 26 #define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds) 27 28 29 extern void netlink_table_grab(void); 30 extern void netlink_table_ungrab(void); 31 32 #define NL_CFG_F_NONROOT_RECV (1 << 0) 33 #define NL_CFG_F_NONROOT_SEND (1 << 1) 34 35 /* optional Netlink kernel configuration parameters */ 36 struct netlink_kernel_cfg { 37 unsigned int groups; 38 unsigned int flags; 39 void (*input)(struct sk_buff *skb); 40 struct mutex *cb_mutex; 41 void (*bind)(int group); 42 }; 43 44 extern struct sock *__netlink_kernel_create(struct net *net, int unit, 45 struct module *module, 46 struct netlink_kernel_cfg *cfg); 47 static inline struct sock * 48 netlink_kernel_create(struct net *net, int unit, struct netlink_kernel_cfg *cfg) 49 { 50 return __netlink_kernel_create(net, unit, THIS_MODULE, cfg); 51 } 52 53 extern void netlink_kernel_release(struct sock *sk); 54 extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups); 55 extern int netlink_change_ngroups(struct sock *sk, unsigned int groups); 56 extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group); 57 extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group); 58 extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err); 59 extern int netlink_has_listeners(struct sock *sk, unsigned int group); 60 extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 portid, int nonblock); 61 extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 portid, 62 __u32 group, gfp_t allocation); 63 extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, 64 __u32 portid, __u32 group, gfp_t allocation, 65 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data), 66 void *filter_data); 67 extern int netlink_set_err(struct sock *ssk, __u32 portid, __u32 group, int code); 68 extern int netlink_register_notifier(struct notifier_block *nb); 69 extern int netlink_unregister_notifier(struct notifier_block *nb); 70 71 /* finegrained unicast helpers: */ 72 struct sock *netlink_getsockbyfilp(struct file *filp); 73 int netlink_attachskb(struct sock *sk, struct sk_buff *skb, 74 long *timeo, struct sock *ssk); 75 void netlink_detachskb(struct sock *sk, struct sk_buff *skb); 76 int netlink_sendskb(struct sock *sk, struct sk_buff *skb); 77 78 /* 79 * skb should fit one page. This choice is good for headerless malloc. 80 * But we should limit to 8K so that userspace does not have to 81 * use enormous buffer sizes on recvmsg() calls just to avoid 82 * MSG_TRUNC when PAGE_SIZE is very large. 83 */ 84 #if PAGE_SIZE < 8192UL 85 #define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE) 86 #else 87 #define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL) 88 #endif 89 90 #define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN) 91 92 93 struct netlink_callback { 94 struct sk_buff *skb; 95 const struct nlmsghdr *nlh; 96 int (*dump)(struct sk_buff * skb, 97 struct netlink_callback *cb); 98 int (*done)(struct netlink_callback *cb); 99 void *data; 100 /* the module that dump function belong to */ 101 struct module *module; 102 u16 family; 103 u16 min_dump_alloc; 104 unsigned int prev_seq, seq; 105 long args[6]; 106 }; 107 108 struct netlink_notify { 109 struct net *net; 110 int portid; 111 int protocol; 112 }; 113 114 struct nlmsghdr * 115 __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags); 116 117 struct netlink_dump_control { 118 int (*dump)(struct sk_buff *skb, struct netlink_callback *); 119 int (*done)(struct netlink_callback *); 120 void *data; 121 struct module *module; 122 u16 min_dump_alloc; 123 }; 124 125 extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, 126 const struct nlmsghdr *nlh, 127 struct netlink_dump_control *control); 128 static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, 129 const struct nlmsghdr *nlh, 130 struct netlink_dump_control *control) 131 { 132 if (!control->module) 133 control->module = THIS_MODULE; 134 135 return __netlink_dump_start(ssk, skb, nlh, control); 136 } 137 138 #endif /* __LINUX_NETLINK_H */ 139