slirp_kern.c revision be8ad5a409ecdbc80d4087eb76746ba15c3a92e2 
1/*
2 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL.
4 */
5
6#include <linux/if_arp.h>
7#include "linux/init.h"
8#include <linux/netdevice.h>
9#include <linux/string.h>
10#include "net_kern.h"
11#include "net_user.h"
12#include "slirp.h"
13
14struct slirp_init {
15	struct arg_list_dummy_wrapper argw;  /* XXX should be simpler... */
16};
17
18void slirp_init(struct net_device *dev, void *data)
19{
20	struct uml_net_private *private;
21	struct slirp_data *spri;
22	struct slirp_init *init = data;
23	int i;
24
25	private = dev->priv;
26	spri = (struct slirp_data *) private->user;
27
28	spri->argw = init->argw;
29	spri->pid = -1;
30	spri->slave = -1;
31	spri->dev = dev;
32
33	slip_proto_init(&spri->slip);
34
35	dev->init = NULL;
36	dev->hard_header_len = 0;
37	dev->header_ops = NULL;
38	dev->addr_len = 0;
39	dev->type = ARPHRD_SLIP;
40	dev->tx_queue_len = 256;
41	dev->flags = IFF_NOARP;
42	printk("SLIRP backend - command line:");
43	for (i = 0; spri->argw.argv[i] != NULL; i++)
44		printk(" '%s'",spri->argw.argv[i]);
45	printk("\n");
46}
47
48static unsigned short slirp_protocol(struct sk_buff *skbuff)
49{
50	return htons(ETH_P_IP);
51}
52
53static int slirp_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
54{
55	return slirp_user_read(fd, skb_mac_header(skb), skb->dev->mtu,
56			       (struct slirp_data *) &lp->user);
57}
58
59static int slirp_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
60{
61	return slirp_user_write(fd, skb->data, skb->len,
62				(struct slirp_data *) &lp->user);
63}
64
65const struct net_kern_info slirp_kern_info = {
66	.init			= slirp_init,
67	.protocol		= slirp_protocol,
68	.read			= slirp_read,
69	.write			= slirp_write,
70};
71
72static int slirp_setup(char *str, char **mac_out, void *data)
73{
74	struct slirp_init *init = data;
75	int i=0;
76
77	*init = ((struct slirp_init) { .argw = { { "slirp", NULL  } } });
78
79	str = split_if_spec(str, mac_out, NULL);
80
81	if (str == NULL) /* no command line given after MAC addr */
82		return 1;
83
84	do {
85		if (i >= SLIRP_MAX_ARGS - 1) {
86			printk(KERN_WARNING "slirp_setup: truncating slirp "
87			       "arguments\n");
88			break;
89		}
90		init->argw.argv[i++] = str;
91		while(*str && *str!=',') {
92			if (*str == '_')
93				*str=' ';
94			str++;
95		}
96		if (*str != ',')
97			break;
98		*str++ = '\0';
99	} while (1);
100
101	init->argw.argv[i] = NULL;
102	return 1;
103}
104
105static struct transport slirp_transport = {
106	.list 		= LIST_HEAD_INIT(slirp_transport.list),
107	.name 		= "slirp",
108	.setup  	= slirp_setup,
109	.user 		= &slirp_user_info,
110	.kern 		= &slirp_kern_info,
111	.private_size 	= sizeof(struct slirp_data),
112	.setup_size 	= sizeof(struct slirp_init),
113};
114
115static int register_slirp(void)
116{
117	register_transport(&slirp_transport);
118	return 0;
119}
120
121late_initcall(register_slirp);
122