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_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
66extern int netlink_has_listeners(struct sock *sk, unsigned int group);
67extern struct sk_buff *netlink_alloc_skb(struct sock *ssk, unsigned int size,
68 u32 dst_portid, gfp_t gfp_mask);
69extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 portid, int nonblock);
70extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 portid,
71 __u32 group, gfp_t allocation);
72extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
73 __u32 portid, __u32 group, gfp_t allocation,
74 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
75 void *filter_data);
76extern int netlink_set_err(struct sock *ssk, __u32 portid, __u32 group, int code);
77extern int netlink_register_notifier(struct notifier_block *nb);
78extern int netlink_unregister_notifier(struct notifier_block *nb);
79
80/* finegrained unicast helpers: */
81struct sock *netlink_getsockbyfilp(struct file *filp);
82int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
83 long *timeo, struct sock *ssk);
84void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
85int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
86
87static inline struct sk_buff *
88netlink_skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
89{
90 struct sk_buff *nskb;
91
92 nskb = skb_clone(skb, gfp_mask);
93 if (!nskb)
94 return NULL;
95
96 /* This is a large skb, set destructor callback to release head */
97 if (is_vmalloc_addr(skb->head))
98 nskb->destructor = skb->destructor;
99
100 return nskb;
101}
102
103/*
104 * skb should fit one page. This choice is good for headerless malloc.
105 * But we should limit to 8K so that userspace does not have to
106 * use enormous buffer sizes on recvmsg() calls just to avoid
107 * MSG_TRUNC when PAGE_SIZE is very large.
108 */
109#if PAGE_SIZE < 8192UL
110#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE)
111#else
112#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL)
113#endif
114
115#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
116
117
118struct netlink_callback {
119 struct sk_buff *skb;
120 const struct nlmsghdr *nlh;
121 int (*dump)(struct sk_buff * skb,
122 struct netlink_callback *cb);
123 int (*done)(struct netlink_callback *cb);
124 void *data;
125 /* the module that dump function belong to */
126 struct module *module;
127 u16 family;
128 u16 min_dump_alloc;
129 unsigned int prev_seq, seq;
130 long args[6];
131};
132
133struct netlink_notify {
134 struct net *net;
135 int portid;
136 int protocol;
137};
138
139struct nlmsghdr *
140__nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags);
141
142struct netlink_dump_control {
143 int (*dump)(struct sk_buff *skb, struct netlink_callback *);
144 int (*done)(struct netlink_callback *);
145 void *data;
146 struct module *module;
147 u16 min_dump_alloc;
148};
149
150extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
151 const struct nlmsghdr *nlh,
152 struct netlink_dump_control *control);
153static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
154 const struct nlmsghdr *nlh,
155 struct netlink_dump_control *control)
156{
157 if (!control->module)
158 control->module = THIS_MODULE;
159
160 return __netlink_dump_start(ssk, skb, nlh, control);
161}
162
163struct netlink_tap {
164 struct net_device *dev;
165 struct module *module;
166 struct list_head list;
167};
168
169extern int netlink_add_tap(struct netlink_tap *nt);
170extern int netlink_remove_tap(struct netlink_tap *nt);
171
172#endif /* __LINUX_NETLINK_H */