Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
11struct net;
12
13static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
14{
15 return (struct nlmsghdr *)skb->data;
16}
17
18enum netlink_skb_flags {
19 NETLINK_SKB_MMAPED = 0x1, /* Packet data is mmaped */
20 NETLINK_SKB_TX = 0x2, /* Packet was sent by userspace */
21 NETLINK_SKB_DELIVERED = 0x4, /* Packet was delivered */
22};
23
24struct netlink_skb_parms {
25 struct scm_creds creds; /* Skb credentials */
26 __u32 portid;
27 __u32 dst_group;
28 __u32 flags;
29 struct sock *sk;
30};
31
32#define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb))
33#define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
34
35
36extern void netlink_table_grab(void);
37extern void netlink_table_ungrab(void);
38
39#define NL_CFG_F_NONROOT_RECV (1 << 0)
40#define NL_CFG_F_NONROOT_SEND (1 << 1)
41
42/* optional Netlink kernel configuration parameters */
43struct netlink_kernel_cfg {
44 unsigned int groups;
45 unsigned int flags;
46 void (*input)(struct sk_buff *skb);
47 struct mutex *cb_mutex;
48 void (*bind)(int group);
49 bool (*compare)(struct net *net, struct sock *sk);
50};
51
52extern struct sock *__netlink_kernel_create(struct net *net, int unit,
53 struct module *module,
54 struct netlink_kernel_cfg *cfg);
55static inline struct sock *
56netlink_kernel_create(struct net *net, int unit, struct netlink_kernel_cfg *cfg)
57{
58 return __netlink_kernel_create(net, unit, THIS_MODULE, cfg);
59}
60
61extern void netlink_kernel_release(struct sock *sk);
62extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
63extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
64extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
65extern void netlink_clear_multicast_users(struct sock *sk, unsigned int group);
66extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
67extern int netlink_has_listeners(struct sock *sk, unsigned int group);
68extern struct sk_buff *netlink_alloc_skb(struct sock *ssk, unsigned int size,
69 u32 dst_portid, gfp_t gfp_mask);
70extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 portid, int nonblock);
71extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 portid,
72 __u32 group, gfp_t allocation);
73extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
74 __u32 portid, __u32 group, gfp_t allocation,
75 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
76 void *filter_data);
77extern int netlink_set_err(struct sock *ssk, __u32 portid, __u32 group, int code);
78extern int netlink_register_notifier(struct notifier_block *nb);
79extern int netlink_unregister_notifier(struct notifier_block *nb);
80
81/* finegrained unicast helpers: */
82struct sock *netlink_getsockbyfilp(struct file *filp);
83int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
84 long *timeo, struct sock *ssk);
85void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
86int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
87
88static inline struct sk_buff *
89netlink_skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
90{
91 struct sk_buff *nskb;
92
93 nskb = skb_clone(skb, gfp_mask);
94 if (!nskb)
95 return NULL;
96
97 /* This is a large skb, set destructor callback to release head */
98 if (is_vmalloc_addr(skb->head))
99 nskb->destructor = skb->destructor;
100
101 return nskb;
102}
103
104/*
105 * skb should fit one page. This choice is good for headerless malloc.
106 * But we should limit to 8K so that userspace does not have to
107 * use enormous buffer sizes on recvmsg() calls just to avoid
108 * MSG_TRUNC when PAGE_SIZE is very large.
109 */
110#if PAGE_SIZE < 8192UL
111#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE)
112#else
113#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL)
114#endif
115
116#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
117
118
119struct netlink_callback {
120 struct sk_buff *skb;
121 const struct nlmsghdr *nlh;
122 int (*dump)(struct sk_buff * skb,
123 struct netlink_callback *cb);
124 int (*done)(struct netlink_callback *cb);
125 void *data;
126 /* the module that dump function belong to */
127 struct module *module;
128 u16 family;
129 u16 min_dump_alloc;
130 unsigned int prev_seq, seq;
131 long args[6];
132};
133
134struct netlink_notify {
135 struct net *net;
136 int portid;
137 int protocol;
138};
139
140struct nlmsghdr *
141__nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags);
142
143struct netlink_dump_control {
144 int (*dump)(struct sk_buff *skb, struct netlink_callback *);
145 int (*done)(struct netlink_callback *);
146 void *data;
147 struct module *module;
148 u16 min_dump_alloc;
149};
150
151extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
152 const struct nlmsghdr *nlh,
153 struct netlink_dump_control *control);
154static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
155 const struct nlmsghdr *nlh,
156 struct netlink_dump_control *control)
157{
158 if (!control->module)
159 control->module = THIS_MODULE;
160
161 return __netlink_dump_start(ssk, skb, nlh, control);
162}
163
164struct netlink_tap {
165 struct net_device *dev;
166 struct module *module;
167 struct list_head list;
168};
169
170extern int netlink_add_tap(struct netlink_tap *nt);
171extern int __netlink_remove_tap(struct netlink_tap *nt);
172extern int netlink_remove_tap(struct netlink_tap *nt);
173
174#endif /* __LINUX_NETLINK_H */