1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 4 */ 5 6 #include <linux/netdevice.h> 7 #include <linux/init.h> 8 #include <linux/skbuff.h> 9 #include <asm/errno.h> 10 #include <net_kern.h> 11 #include "tuntap.h" 12 13 struct tuntap_init { 14 char *dev_name; 15 char *gate_addr; 16 }; 17 18 static void tuntap_init(struct net_device *dev, void *data) 19 { 20 struct uml_net_private *pri; 21 struct tuntap_data *tpri; 22 struct tuntap_init *init = data; 23 24 pri = netdev_priv(dev); 25 tpri = (struct tuntap_data *) pri->user; 26 tpri->dev_name = init->dev_name; 27 tpri->fixed_config = (init->dev_name != NULL); 28 tpri->gate_addr = init->gate_addr; 29 tpri->fd = -1; 30 tpri->dev = dev; 31 32 printk(KERN_INFO "TUN/TAP backend - "); 33 if (tpri->gate_addr != NULL) 34 printk(KERN_CONT "IP = %s", tpri->gate_addr); 35 printk(KERN_CONT "\n"); 36 } 37 38 static int tuntap_read(int fd, struct sk_buff *skb, struct uml_net_private *lp) 39 { 40 return net_read(fd, skb_mac_header(skb), 41 skb->dev->mtu + ETH_HEADER_OTHER); 42 } 43 44 static int tuntap_write(int fd, struct sk_buff *skb, struct uml_net_private *lp) 45 { 46 return net_write(fd, skb->data, skb->len); 47 } 48 49 const struct net_kern_info tuntap_kern_info = { 50 .init = tuntap_init, 51 .protocol = eth_protocol, 52 .read = tuntap_read, 53 .write = tuntap_write, 54 }; 55 56 int tuntap_setup(char *str, char **mac_out, void *data) 57 { 58 struct tuntap_init *init = data; 59 60 *init = ((struct tuntap_init) 61 { .dev_name = NULL, 62 .gate_addr = NULL }); 63 if (tap_setup_common(str, "tuntap", &init->dev_name, mac_out, 64 &init->gate_addr)) 65 return 0; 66 67 return 1; 68 } 69 70 static struct transport tuntap_transport = { 71 .list = LIST_HEAD_INIT(tuntap_transport.list), 72 .name = "tuntap", 73 .setup = tuntap_setup, 74 .user = &tuntap_user_info, 75 .kern = &tuntap_kern_info, 76 .private_size = sizeof(struct tuntap_data), 77 .setup_size = sizeof(struct tuntap_init), 78 }; 79 80 static int register_tuntap(void) 81 { 82 register_transport(&tuntap_transport); 83 return 0; 84 } 85 86 late_initcall(register_tuntap); 87