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17#include <linux/module.h>
18
19#include <linux/errno.h>
20#include <linux/kernel.h>
21#include <linux/major.h>
22#include <linux/sched.h>
23#include <linux/slab.h>
24#include <linux/skbuff.h>
25#include <linux/netlink.h>
26#include <linux/poll.h>
27#include <linux/init.h>
28#include <linux/devfs_fs_kernel.h>
29#include <linux/smp_lock.h>
30
31#include <asm/bitops.h>
32#include <asm/system.h>
33#include <asm/uaccess.h>
34
35static long open_map;
36static struct socket *netlink_user[MAX_LINKS];
37
38
39
40
41
42static unsigned int netlink_poll(struct file *file, poll_table * wait)
43{
44 struct socket *sock = netlink_user[MINOR(file->f_dentry->d_inode->i_rdev)];
45
46 if (sock->ops->poll==NULL)
47 return 0;
48 return sock->ops->poll(file, sock, wait);
49}
50
51
52
53
54
55static ssize_t netlink_write(struct file * file, const char * buf,
56 size_t count, loff_t *pos)
57{
58 struct inode *inode = file->f_dentry->d_inode;
59 struct socket *sock = netlink_user[MINOR(inode->i_rdev)];
60 struct msghdr msg;
61 struct iovec iov;
62
63 iov.iov_base = (void*)buf;
64 iov.iov_len = count;
65 msg.msg_name=NULL;
66 msg.msg_namelen=0;
67 msg.msg_controllen=0;
68 msg.msg_flags=0;
69 msg.msg_iov=&iov;
70 msg.msg_iovlen=1;
71
72 return sock_sendmsg(sock, &msg, count);
73}
74
75
76
77
78
79static ssize_t netlink_read(struct file * file, char * buf,
80 size_t count, loff_t *pos)
81{
82 struct inode *inode = file->f_dentry->d_inode;
83 struct socket *sock = netlink_user[MINOR(inode->i_rdev)];
84 struct msghdr msg;
85 struct iovec iov;
86
87 iov.iov_base = buf;
88 iov.iov_len = count;
89 msg.msg_name=NULL;
90 msg.msg_namelen=0;
91 msg.msg_controllen=0;
92 msg.msg_flags=0;
93 msg.msg_iov=&iov;
94 msg.msg_iovlen=1;
95 if (file->f_flags&O_NONBLOCK)
96 msg.msg_flags=MSG_DONTWAIT;
97
98 return sock_recvmsg(sock, &msg, count, msg.msg_flags);
99}
100
101static int netlink_open(struct inode * inode, struct file * file)
102{
103 unsigned int minor = MINOR(inode->i_rdev);
104 struct socket *sock;
105 struct sockaddr_nl nladdr;
106 int err;
107
108 if (minor>=MAX_LINKS)
109 return -ENODEV;
110 if (test_and_set_bit(minor, &open_map))
111 return -EBUSY;
112
113 err = sock_create(PF_NETLINK, SOCK_RAW, minor, &sock);
114 if (err < 0)
115 goto out;
116
117 memset(&nladdr, 0, sizeof(nladdr));
118 nladdr.nl_family = AF_NETLINK;
119 nladdr.nl_groups = ~0;
120 if ((err = sock->ops->bind(sock, (struct sockaddr*)&nladdr, sizeof(nladdr))) < 0) {
121 sock_release(sock);
122 goto out;
123 }
124
125 netlink_user[minor] = sock;
126 return 0;
127
128out:
129 clear_bit(minor, &open_map);
130 return err;
131}
132
133static int netlink_release(struct inode * inode, struct file * file)
134{
135 unsigned int minor = MINOR(inode->i_rdev);
136 struct socket *sock;
137
138 sock = netlink_user[minor];
139 netlink_user[minor] = NULL;
140 clear_bit(minor, &open_map);
141 sock_release(sock);
142 return 0;
143}
144
145
146static int netlink_ioctl(struct inode *inode, struct file *file,
147 unsigned int cmd, unsigned long arg)
148{
149 unsigned int minor = MINOR(inode->i_rdev);
150 int retval = 0;
151
152 if (minor >= MAX_LINKS)
153 return -ENODEV;
154 switch ( cmd ) {
155 default:
156 retval = -EINVAL;
157 }
158 return retval;
159}
160
161
162static struct file_operations netlink_fops = {
163 owner: THIS_MODULE,
164 llseek: no_llseek,
165 read: netlink_read,
166 write: netlink_write,
167 poll: netlink_poll,
168 ioctl: netlink_ioctl,
169 open: netlink_open,
170 release: netlink_release,
171};
172
173static devfs_handle_t devfs_handle;
174
175static void __init make_devfs_entries (const char *name, int minor)
176{
177 devfs_register (devfs_handle, name, DEVFS_FL_DEFAULT,
178 NETLINK_MAJOR, minor,
179 S_IFCHR | S_IRUSR | S_IWUSR,
180 &netlink_fops, NULL);
181}
182
183int __init init_netlink(void)
184{
185 if (devfs_register_chrdev(NETLINK_MAJOR,"netlink", &netlink_fops)) {
186 printk(KERN_ERR "netlink: unable to get major %d\n", NETLINK_MAJOR);
187 return -EIO;
188 }
189 devfs_handle = devfs_mk_dir (NULL, "netlink", NULL);
190
191 make_devfs_entries ("route", 0);
192 make_devfs_entries ("skip", 1);
193 make_devfs_entries ("usersock", 2);
194 make_devfs_entries ("fwmonitor", 3);
195 make_devfs_entries ("tcpdiag", 4);
196 make_devfs_entries ("arpd", 8);
197 make_devfs_entries ("route6", 11);
198 make_devfs_entries ("ip6_fw", 13);
199 make_devfs_entries ("dnrtmsg", 13);
200 devfs_register_series (devfs_handle, "tap%u", 16, DEVFS_FL_DEFAULT,
201 NETLINK_MAJOR, 16,
202 S_IFCHR | S_IRUSR | S_IWUSR,
203 &netlink_fops, NULL);
204 return 0;
205}
206
207#ifdef MODULE
208
209MODULE_LICENSE("GPL");
210
211int init_module(void)
212{
213 printk(KERN_INFO "Network Kernel/User communications module 0.04\n");
214 return init_netlink();
215}
216
217void cleanup_module(void)
218{
219 devfs_unregister (devfs_handle);
220 devfs_unregister_chrdev(NETLINK_MAJOR, "netlink");
221}
222
223#endif
224
