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 NETLINK_SKB_DST = 0x8, /* Dst set in sendto or sendmsg */
23};
24
25struct netlink_skb_parms {
26 struct scm_creds creds; /* Skb credentials */
27 __u32 portid;
28 __u32 dst_group;
29 __u32 flags;
30 struct sock *sk;
31 bool nsid_is_set;
32 int nsid;
33};
34
35#define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb))
36#define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
37
38
39extern void netlink_table_grab(void);
40extern void netlink_table_ungrab(void);
41
42#define NL_CFG_F_NONROOT_RECV (1 << 0)
43#define NL_CFG_F_NONROOT_SEND (1 << 1)
44
45/* optional Netlink kernel configuration parameters */
46struct netlink_kernel_cfg {
47 unsigned int groups;
48 unsigned int flags;
49 void (*input)(struct sk_buff *skb);
50 struct mutex *cb_mutex;
51 int (*bind)(struct net *net, int group);
52 void (*unbind)(struct net *net, int group);
53 bool (*compare)(struct net *net, struct sock *sk);
54};
55
56extern struct sock *__netlink_kernel_create(struct net *net, int unit,
57 struct module *module,
58 struct netlink_kernel_cfg *cfg);
59static inline struct sock *
60netlink_kernel_create(struct net *net, int unit, struct netlink_kernel_cfg *cfg)
61{
62 return __netlink_kernel_create(net, unit, THIS_MODULE, cfg);
63}
64
65extern void netlink_kernel_release(struct sock *sk);
66extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
67extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
68extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
69extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
70extern int netlink_has_listeners(struct sock *sk, unsigned int group);
71extern struct sk_buff *netlink_alloc_skb(struct sock *ssk, unsigned int size,
72 u32 dst_portid, gfp_t gfp_mask);
73extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 portid, int nonblock);
74extern int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 portid,
75 __u32 group, gfp_t allocation);
76extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
77 __u32 portid, __u32 group, gfp_t allocation,
78 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
79 void *filter_data);
80extern int netlink_set_err(struct sock *ssk, __u32 portid, __u32 group, int code);
81extern int netlink_register_notifier(struct notifier_block *nb);
82extern int netlink_unregister_notifier(struct notifier_block *nb);
83
84/* finegrained unicast helpers: */
85struct sock *netlink_getsockbyfilp(struct file *filp);
86int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
87 long *timeo, struct sock *ssk);
88void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
89int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
90
91static inline struct sk_buff *
92netlink_skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
93{
94 struct sk_buff *nskb;
95
96 nskb = skb_clone(skb, gfp_mask);
97 if (!nskb)
98 return NULL;
99
100 /* This is a large skb, set destructor callback to release head */
101 if (is_vmalloc_addr(skb->head))
102 nskb->destructor = skb->destructor;
103
104 return nskb;
105}
106
107/*
108 * skb should fit one page. This choice is good for headerless malloc.
109 * But we should limit to 8K so that userspace does not have to
110 * use enormous buffer sizes on recvmsg() calls just to avoid
111 * MSG_TRUNC when PAGE_SIZE is very large.
112 */
113#if PAGE_SIZE < 8192UL
114#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE)
115#else
116#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL)
117#endif
118
119#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
120
121
122struct netlink_callback {
123 struct sk_buff *skb;
124 const struct nlmsghdr *nlh;
125 int (*dump)(struct sk_buff * skb,
126 struct netlink_callback *cb);
127 int (*done)(struct netlink_callback *cb);
128 void *data;
129 /* the module that dump function belong to */
130 struct module *module;
131 u16 family;
132 u16 min_dump_alloc;
133 unsigned int prev_seq, seq;
134 long args[6];
135};
136
137struct netlink_notify {
138 struct net *net;
139 u32 portid;
140 int protocol;
141};
142
143struct nlmsghdr *
144__nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags);
145
146struct netlink_dump_control {
147 int (*dump)(struct sk_buff *skb, struct netlink_callback *);
148 int (*done)(struct netlink_callback *);
149 void *data;
150 struct module *module;
151 u16 min_dump_alloc;
152};
153
154extern int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
155 const struct nlmsghdr *nlh,
156 struct netlink_dump_control *control);
157static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
158 const struct nlmsghdr *nlh,
159 struct netlink_dump_control *control)
160{
161 if (!control->module)
162 control->module = THIS_MODULE;
163
164 return __netlink_dump_start(ssk, skb, nlh, control);
165}
166
167struct netlink_tap {
168 struct net_device *dev;
169 struct module *module;
170 struct list_head list;
171};
172
173extern int netlink_add_tap(struct netlink_tap *nt);
174extern int netlink_remove_tap(struct netlink_tap *nt);
175
176bool __netlink_ns_capable(const struct netlink_skb_parms *nsp,
177 struct user_namespace *ns, int cap);
178bool netlink_ns_capable(const struct sk_buff *skb,
179 struct user_namespace *ns, int cap);
180bool netlink_capable(const struct sk_buff *skb, int cap);
181bool netlink_net_capable(const struct sk_buff *skb, int cap);
182
183#endif /* __LINUX_NETLINK_H */