2 * DECnet An implementation of the DECnet protocol suite for the LINUX
3 * operating system. DECnet is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * DECnet Routing Message Grabulator
8 * (C) 2000 ChyGwyn Limited - http://www.chygwyn.com/
9 * This code may be copied under the GPL v.2 or at your option
12 * Author: Steven Whitehouse <steve@chygwyn.com>
15 #include <linux/module.h>
16 #include <linux/skbuff.h>
17 #include <linux/init.h>
18 #include <linux/netdevice.h>
19 #include <linux/netfilter.h>
20 #include <linux/spinlock.h>
21 #include <linux/netlink.h>
26 #include <net/dn_route.h>
28 #include <linux/netfilter_decnet.h>
30 static struct sock
*dnrmg
= NULL
;
33 static struct sk_buff
*dnrmg_build_message(struct sk_buff
*rt_skb
, int *errp
)
35 struct sk_buff
*skb
= NULL
;
37 unsigned char *old_tail
;
40 struct nf_dn_rtmsg
*rtm
;
42 size
= NLMSG_SPACE(rt_skb
->len
);
43 size
+= NLMSG_ALIGN(sizeof(struct nf_dn_rtmsg
));
44 skb
= alloc_skb(size
, GFP_ATOMIC
);
48 nlh
= NLMSG_PUT(skb
, 0, 0, 0, size
- sizeof(*nlh
));
49 rtm
= (struct nf_dn_rtmsg
*)NLMSG_DATA(nlh
);
50 rtm
->nfdn_ifindex
= rt_skb
->dev
->ifindex
;
51 ptr
= NFDN_RTMSG(rtm
);
52 memcpy(ptr
, rt_skb
->data
, rt_skb
->len
);
53 nlh
->nlmsg_len
= skb
->tail
- old_tail
;
61 printk(KERN_ERR
"dn_rtmsg: error creating netlink message\n");
65 static void dnrmg_send_peer(struct sk_buff
*skb
)
70 unsigned char flags
= *skb
->data
;
72 switch(flags
& DN_RT_CNTL_MSK
) {
74 group
= DNRMG_L1_GROUP
;
77 group
= DNRMG_L2_GROUP
;
83 skb2
= dnrmg_build_message(skb
, &status
);
86 NETLINK_CB(skb2
).dst_groups
= group
;
87 netlink_broadcast(dnrmg
, skb2
, 0, group
, GFP_ATOMIC
);
91 static unsigned int dnrmg_hook(unsigned int hook
,
92 struct sk_buff
**pskb
,
93 const struct net_device
*in
,
94 const struct net_device
*out
,
95 int (*okfn
)(struct sk_buff
*))
97 dnrmg_send_peer(*pskb
);
102 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
104 static inline void dnrmg_receive_user_skb(struct sk_buff
*skb
)
106 struct nlmsghdr
*nlh
= (struct nlmsghdr
*)skb
->data
;
108 if (nlh
->nlmsg_len
< sizeof(*nlh
) || skb
->len
< nlh
->nlmsg_len
)
111 if (!cap_raised(NETLINK_CB(skb
).eff_cap
, CAP_NET_ADMIN
))
112 RCV_SKB_FAIL(-EPERM
);
114 /* Eventually we might send routing messages too */
116 RCV_SKB_FAIL(-EINVAL
);
119 static void dnrmg_receive_user_sk(struct sock
*sk
, int len
)
122 unsigned int qlen
= skb_queue_len(&sk
->sk_receive_queue
);
124 for (; qlen
&& (skb
= skb_dequeue(&sk
->sk_receive_queue
)); qlen
--) {
125 dnrmg_receive_user_skb(skb
);
130 static struct nf_hook_ops dnrmg_ops
= {
133 .hooknum
= NF_DN_ROUTE
,
134 .priority
= NF_DN_PRI_DNRTMSG
,
137 static int __init
init(void)
141 dnrmg
= netlink_kernel_create(NETLINK_DNRTMSG
, dnrmg_receive_user_sk
);
143 printk(KERN_ERR
"dn_rtmsg: Cannot create netlink socket");
147 rv
= nf_register_hook(&dnrmg_ops
);
149 sock_release(dnrmg
->sk_socket
);
155 static void __exit
fini(void)
157 nf_unregister_hook(&dnrmg_ops
);
158 sock_release(dnrmg
->sk_socket
);
162 MODULE_DESCRIPTION("DECnet Routing Message Grabulator");
163 MODULE_AUTHOR("Steven Whitehouse <steve@chygwyn.com>");
164 MODULE_LICENSE("GPL");