1
2
3
4
5
6
7
8
9#include <linux/init.h>
10#include <linux/netdevice.h>
11#include "etap.h"
12#include <net_kern.h>
13
14struct ethertap_init {
15 char *dev_name;
16 char *gate_addr;
17};
18
19static void etap_init(struct net_device *dev, void *data)
20{
21 struct uml_net_private *pri;
22 struct ethertap_data *epri;
23 struct ethertap_init *init = data;
24
25 pri = netdev_priv(dev);
26 epri = (struct ethertap_data *) pri->user;
27 epri->dev_name = init->dev_name;
28 epri->gate_addr = init->gate_addr;
29 epri->data_fd = -1;
30 epri->control_fd = -1;
31 epri->dev = dev;
32
33 printk(KERN_INFO "ethertap backend - %s", epri->dev_name);
34 if (epri->gate_addr != NULL)
35 printk(KERN_CONT ", IP = %s", epri->gate_addr);
36 printk(KERN_CONT "\n");
37}
38
39static int etap_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
40{
41 int len;
42
43 len = net_recvfrom(fd, skb_mac_header(skb),
44 skb->dev->mtu + 2 + ETH_HEADER_ETHERTAP);
45 if (len <= 0)
46 return(len);
47
48 skb_pull(skb, 2);
49 len -= 2;
50 return len;
51}
52
53static int etap_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
54{
55 skb_push(skb, 2);
56 return net_send(fd, skb->data, skb->len);
57}
58
59const struct net_kern_info ethertap_kern_info = {
60 .init = etap_init,
61 .protocol = eth_protocol,
62 .read = etap_read,
63 .write = etap_write,
64};
65
66int ethertap_setup(char *str, char **mac_out, void *data)
67{
68 struct ethertap_init *init = data;
69
70 *init = ((struct ethertap_init)
71 { .dev_name = NULL,
72 .gate_addr = NULL });
73 if (tap_setup_common(str, "ethertap", &init->dev_name, mac_out,
74 &init->gate_addr))
75 return 0;
76 if (init->dev_name == NULL) {
77 printk(KERN_ERR "ethertap_setup : Missing tap device name\n");
78 return 0;
79 }
80
81 return 1;
82}
83
84static struct transport ethertap_transport = {
85 .list = LIST_HEAD_INIT(ethertap_transport.list),
86 .name = "ethertap",
87 .setup = ethertap_setup,
88 .user = ðertap_user_info,
89 .kern = ðertap_kern_info,
90 .private_size = sizeof(struct ethertap_data),
91 .setup_size = sizeof(struct ethertap_init),
92};
93
94static int register_ethertap(void)
95{
96 register_transport(ðertap_transport);
97 return 0;
98}
99
100late_initcall(register_ethertap);
101