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14#include "linux/init.h"
15#include <linux/netdevice.h>
16#include "mcast.h"
17#include "net_kern.h"
18
19struct mcast_init {
20 char *addr;
21 int port;
22 int ttl;
23};
24
25static void mcast_init(struct net_device *dev, void *data)
26{
27 struct uml_net_private *pri;
28 struct mcast_data *dpri;
29 struct mcast_init *init = data;
30
31 pri = dev->priv;
32 dpri = (struct mcast_data *) pri->user;
33 dpri->addr = init->addr;
34 dpri->port = init->port;
35 dpri->ttl = init->ttl;
36 dpri->dev = dev;
37
38 printk("mcast backend multicast address: %s:%u, TTL:%u\n",
39 dpri->addr, dpri->port, dpri->ttl);
40}
41
42static int mcast_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
43{
44 return net_recvfrom(fd, skb_mac_header(skb),
45 skb->dev->mtu + ETH_HEADER_OTHER);
46}
47
48static int mcast_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
49{
50 return mcast_user_write(fd, skb->data, skb->len,
51 (struct mcast_data *) &lp->user);
52}
53
54static const struct net_kern_info mcast_kern_info = {
55 .init = mcast_init,
56 .protocol = eth_protocol,
57 .read = mcast_read,
58 .write = mcast_write,
59};
60
61int mcast_setup(char *str, char **mac_out, void *data)
62{
63 struct mcast_init *init = data;
64 char *port_str = NULL, *ttl_str = NULL, *remain;
65 char *last;
66
67 *init = ((struct mcast_init)
68 { .addr = "239.192.168.1",
69 .port = 1102,
70 .ttl = 1 });
71
72 remain = split_if_spec(str, mac_out, &init->addr, &port_str, &ttl_str,
73 NULL);
74 if (remain != NULL) {
75 printk(KERN_ERR "mcast_setup - Extra garbage on "
76 "specification : '%s'\n", remain);
77 return 0;
78 }
79
80 if (port_str != NULL) {
81 init->port = simple_strtoul(port_str, &last, 10);
82 if ((*last != '\0') || (last == port_str)) {
83 printk(KERN_ERR "mcast_setup - Bad port : '%s'\n",
84 port_str);
85 return 0;
86 }
87 }
88
89 if (ttl_str != NULL) {
90 init->ttl = simple_strtoul(ttl_str, &last, 10);
91 if ((*last != '\0') || (last == ttl_str)) {
92 printk(KERN_ERR "mcast_setup - Bad ttl : '%s'\n",
93 ttl_str);
94 return 0;
95 }
96 }
97
98 printk(KERN_INFO "Configured mcast device: %s:%u-%u\n", init->addr,
99 init->port, init->ttl);
100
101 return 1;
102}
103
104static struct transport mcast_transport = {
105 .list = LIST_HEAD_INIT(mcast_transport.list),
106 .name = "mcast",
107 .setup = mcast_setup,
108 .user = &mcast_user_info,
109 .kern = &mcast_kern_info,
110 .private_size = sizeof(struct mcast_data),
111 .setup_size = sizeof(struct mcast_init),
112};
113
114static int register_mcast(void)
115{
116 register_transport(&mcast_transport);
117 return 0;
118}
119
120late_initcall(register_mcast);
121