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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef __LINUX_NETLINK_H
2#define __LINUX_NETLINK_H
3
Linus Torvalds1da177e2005-04-16 15:20:36 -07004
5#include <linux/capability.h>
6#include <linux/skbuff.h>
Pablo Neira Ayusoabb17e62012-09-21 09:35:38 +00007#include <linux/export.h>
Eric W. Biedermandbe9a412012-09-06 18:20:01 +00008#include <net/scm.h>
David Howells607ca462012-10-13 10:46:48 +01009#include <uapi/linux/netlink.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070010
Ollie Wild56b49f42010-09-22 05:54:54 +000011struct net;
12
Arnaldo Carvalho de Melob529ccf2007-04-25 19:08:35 -070013static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
14{
15 return (struct nlmsghdr *)skb->data;
16}
17
Patrick McHardy9652e932013-04-17 06:47:02 +000018enum netlink_skb_flags {
Eric W. Biederman2d7a85f2014-05-30 11:04:00 -070019 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 */
Patrick McHardy9652e932013-04-17 06:47:02 +000023};
24
Eric Dumazetd94d9fe2009-11-04 09:50:58 -080025struct netlink_skb_parms {
Eric W. Biedermandbe9a412012-09-06 18:20:01 +000026 struct scm_creds creds; /* Skb credentials */
Eric W. Biederman15e47302012-09-07 20:12:54 +000027 __u32 portid;
Patrick McHardyd629b832005-08-14 19:27:50 -070028 __u32 dst_group;
Patrick McHardy9652e932013-04-17 06:47:02 +000029 __u32 flags;
Patrick McHardye32123e2013-04-17 06:46:57 +000030 struct sock *sk;
Nicolas Dichtel59324cf2015-05-07 11:02:53 +020031 bool nsid_is_set;
32 int nsid;
Linus Torvalds1da177e2005-04-16 15:20:36 -070033};
34
35#define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb))
36#define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
37
38
Johannes Bergd136f1b2009-09-12 03:03:15 +000039extern void netlink_table_grab(void);
40extern void netlink_table_ungrab(void);
41
Pablo Neira Ayuso9785e102012-09-08 02:53:53 +000042#define NL_CFG_F_NONROOT_RECV (1 << 0)
43#define NL_CFG_F_NONROOT_SEND (1 << 1)
44
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +000045/* optional Netlink kernel configuration parameters */
46struct netlink_kernel_cfg {
47 unsigned int groups;
David S. Millerc9d2ea92012-09-23 02:09:23 -040048 unsigned int flags;
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +000049 void (*input)(struct sk_buff *skb);
50 struct mutex *cb_mutex;
Johannes Berg023e2cf2014-12-23 21:00:06 +010051 int (*bind)(struct net *net, int group);
52 void (*unbind)(struct net *net, int group);
Gao fengda12c902013-06-06 14:49:11 +080053 bool (*compare)(struct net *net, struct sock *sk);
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +000054};
55
Pablo Neira Ayuso9f00d972012-09-08 02:53:54 +000056extern 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
Denis V. Lunevb7c6ba62008-01-28 14:41:19 -080065extern void netlink_kernel_release(struct sock *sk);
Johannes Bergd136f1b2009-09-12 03:03:15 +000066extern int __netlink_change_ngroups(struct sock *sk, unsigned int groups);
Johannes Bergb4ff4f02007-07-18 15:46:06 -070067extern int netlink_change_ngroups(struct sock *sk, unsigned int groups);
Johannes Bergb8273572009-09-24 15:44:05 -070068extern void __netlink_clear_multicast_users(struct sock *sk, unsigned int group);
Linus Torvalds1da177e2005-04-16 15:20:36 -070069extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err);
Patrick McHardy4277a082006-03-20 18:52:01 -080070extern int netlink_has_listeners(struct sock *sk, unsigned int group);
Patrick McHardyf9c22882013-04-17 06:47:04 +000071extern struct sk_buff *netlink_alloc_skb(struct sock *ssk, unsigned int size,
72 u32 dst_portid, gfp_t gfp_mask);
Eric W. Biederman15e47302012-09-07 20:12:54 +000073extern 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,
Al Virodd0fc662005-10-07 07:46:04 +010075 __u32 group, gfp_t allocation);
Eric W. Biederman910a7e92010-05-04 17:36:46 -070076extern int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
Eric W. Biederman15e47302012-09-07 20:12:54 +000077 __u32 portid, __u32 group, gfp_t allocation,
Eric W. Biederman910a7e92010-05-04 17:36:46 -070078 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
79 void *filter_data);
Eric W. Biederman15e47302012-09-07 20:12:54 +000080extern int netlink_set_err(struct sock *ssk, __u32 portid, __u32 group, int code);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081extern 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);
Denis V. Lunev9457afe2008-06-05 11:23:39 -070086int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
Patrick McHardyc3d8d1e2007-11-07 02:42:09 -080087 long *timeo, struct sock *ssk);
Linus Torvalds1da177e2005-04-16 15:20:36 -070088void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
Denis V. Lunev7ee015e2007-10-10 21:14:03 -070089int netlink_sendskb(struct sock *sk, struct sk_buff *skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070090
Pablo Neira3a365152013-06-28 03:04:23 +020091static 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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107/*
108 * skb should fit one page. This choice is good for headerless malloc.
David S. Millerfc910a22007-03-25 20:27:59 -0700109 * 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.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 */
David S. Millerfc910a22007-03-25 20:27:59 -0700113#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
Thomas Graf339bf982006-11-10 14:10:15 -0800119#define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
121
Eric Dumazetd94d9fe2009-11-04 09:50:58 -0800122struct netlink_callback {
Patrick McHardy3a6c2b42009-08-25 16:07:40 +0200123 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);
Pablo Neira Ayuso7175c882012-02-24 14:30:16 +0000128 void *data;
Gao feng6dc878a2012-10-04 20:15:48 +0000129 /* the module that dump function belong to */
130 struct module *module;
Greg Rosec7ac8672011-06-10 01:27:09 +0000131 u16 family;
132 u16 min_dump_alloc;
Johannes Berg670dc282011-06-20 13:40:46 +0200133 unsigned int prev_seq, seq;
Patrick McHardy3a6c2b42009-08-25 16:07:40 +0200134 long args[6];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135};
136
Eric Dumazetd94d9fe2009-11-04 09:50:58 -0800137struct netlink_notify {
Eric W. Biedermanb4b51022007-09-12 13:05:38 +0200138 struct net *net;
Richard Weinberger0392d092015-04-13 00:52:35 +0200139 u32 portid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 int protocol;
141};
142
Denys Vlasenkoa46621a2012-01-30 15:22:06 -0500143struct nlmsghdr *
Eric W. Biederman15e47302012-09-07 20:12:54 +0000144__nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145
Pablo Neira Ayuso80d326f2012-02-24 14:30:15 +0000146struct netlink_dump_control {
147 int (*dump)(struct sk_buff *skb, struct netlink_callback *);
Gao feng6dc878a2012-10-04 20:15:48 +0000148 int (*done)(struct netlink_callback *);
Pablo Neira Ayuso7175c882012-02-24 14:30:16 +0000149 void *data;
Gao feng6dc878a2012-10-04 20:15:48 +0000150 struct module *module;
Pablo Neira Ayuso80d326f2012-02-24 14:30:15 +0000151 u16 min_dump_alloc;
152};
153
Gao feng6dc878a2012-10-04 20:15:48 +0000154extern 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}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166
Daniel Borkmannbcbde0d2013-06-21 19:38:07 +0200167struct 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);
Daniel Borkmannbcbde0d2013-06-21 19:38:07 +0200174extern int netlink_remove_tap(struct netlink_tap *nt);
175
Eric W. Biedermanaa4cf942014-04-23 14:28:03 -0700176bool __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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183#endif /* __LINUX_NETLINK_H */