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/*
* Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
* James Leu (jleu@mindspring.net).
* Copyright (C) 2001 by various other people who didn't put their name here.
* Licensed under the GPL.
*/
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include "etap.h"
#include "os.h"
#include "net_user.h"
#include "um_malloc.h"
#define MAX_PACKET ETH_MAX_PACKET
static int etap_user_init(void *data, void *dev)
{
struct ethertap_data *pri = data;
pri->dev = dev;
return 0;
}
struct addr_change {
enum { ADD_ADDR, DEL_ADDR } what;
unsigned char addr[4];
unsigned char netmask[4];
};
static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
int fd)
{
struct addr_change change;
char *output;
int n;
change.what = op;
memcpy(change.addr, addr, sizeof(change.addr));
memcpy(change.netmask, netmask, sizeof(change.netmask));
CATCH_EINTR(n = write(fd, &change, sizeof(change)));
if (n != sizeof(change)) {
printk(UM_KERN_ERR "etap_change - request failed, err = %d\n",
errno);
return;
}
output = uml_kmalloc(UM_KERN_PAGE_SIZE, UM_GFP_KERNEL);
if (output == NULL)
printk(UM_KERN_ERR "etap_change : Failed to allocate output "
"buffer\n");
read_output(fd, output, UM_KERN_PAGE_SIZE);
if (output != NULL) {
printk("%s", output);
kfree(output);
}
}
static void etap_open_addr(unsigned char *addr, unsigned char *netmask,
void *arg)
{
etap_change(ADD_ADDR, addr, netmask, *((int *) arg));
}
static void etap_close_addr(unsigned char *addr, unsigned char *netmask,
void *arg)
{
etap_change(DEL_ADDR, addr, netmask, *((int *) arg));
}
struct etap_pre_exec_data {
int control_remote;
int control_me;
int data_me;
};
static void etap_pre_exec(void *arg)
{
struct etap_pre_exec_data *data = arg;
dup2(data->control_remote, 1);
close(data->data_me);
close(data->control_me);
}
static int etap_tramp(char *dev, char *gate, int control_me,
int control_remote, int data_me, int data_remote)
{
struct etap_pre_exec_data pe_data;
int pid, err, n;
char version_buf[sizeof("nnnnn\0")];
char data_fd_buf[sizeof("nnnnnn\0")];
char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
data_fd_buf, gate_buf, NULL };
char *nosetup_args[] = { "uml_net", version_buf, "ethertap",
dev, data_fd_buf, NULL };
char **args, c;
sprintf(data_fd_buf, "%d", data_remote);
sprintf(version_buf, "%d", UML_NET_VERSION);
if (gate != NULL) {
strcpy(gate_buf, gate);
args = setup_args;
}
else args = nosetup_args;
err = 0;
pe_data.control_remote = control_remote;
pe_data.control_me = control_me;
pe_data.data_me = data_me;
pid = run_helper(etap_pre_exec, &pe_data, args);
if (pid < 0)
err = pid;
close(data_remote);
close(control_remote);
CATCH_EINTR(n = read(control_me, &c, sizeof(c)));
if (n != sizeof(c)) {
err = -errno;
printk(UM_KERN_ERR "etap_tramp : read of status failed, "
"err = %d\n", -err);
return err;
}
if (c != 1) {
printk(UM_KERN_ERR "etap_tramp : uml_net failed\n");
err = helper_wait(pid);
}
return err;
}
static int etap_open(void *data)
{
struct ethertap_data *pri = data;
char *output;
int data_fds[2], control_fds[2], err, output_len;
err = tap_open_common(pri->dev, pri->gate_addr);
if (err)
return err;
err = socketpair(AF_UNIX, SOCK_DGRAM, 0, data_fds);
if (err) {
err = -errno;
printk(UM_KERN_ERR "etap_open - data socketpair failed - "
"err = %d\n", errno);
return err;
}
err = socketpair(AF_UNIX, SOCK_STREAM, 0, control_fds);
if (err) {
err = -errno;
printk(UM_KERN_ERR "etap_open - control socketpair failed - "
"err = %d\n", errno);
goto out_close_data;
}
err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0],
control_fds[1], data_fds[0], data_fds[1]);
output_len = UM_KERN_PAGE_SIZE;
output = uml_kmalloc(output_len, UM_GFP_KERNEL);
read_output(control_fds[0], output, output_len);
if (output == NULL)
printk(UM_KERN_ERR "etap_open : failed to allocate output "
"buffer\n");
else {
printk("%s", output);
kfree(output);
}
if (err < 0) {
printk(UM_KERN_ERR "etap_tramp failed - err = %d\n", -err);
goto out_close_control;
}
pri->data_fd = data_fds[0];
pri->control_fd = control_fds[0];
iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
return data_fds[0];
out_close_control:
close(control_fds[0]);
close(control_fds[1]);
out_close_data:
close(data_fds[0]);
close(data_fds[1]);
return err;
}
static void etap_close(int fd, void *data)
{
struct ethertap_data *pri = data;
iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
close(fd);
if (shutdown(pri->data_fd, SHUT_RDWR) < 0)
printk(UM_KERN_ERR "etap_close - shutdown data socket failed, "
"errno = %d\n", errno);
if (shutdown(pri->control_fd, SHUT_RDWR) < 0)
printk(UM_KERN_ERR "etap_close - shutdown control socket "
"failed, errno = %d\n", errno);
close(pri->data_fd);
pri->data_fd = -1;
close(pri->control_fd);
pri->control_fd = -1;
}
static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
void *data)
{
struct ethertap_data *pri = data;
tap_check_ips(pri->gate_addr, addr);
if (pri->control_fd == -1)
return;
etap_open_addr(addr, netmask, &pri->control_fd);
}
static void etap_del_addr(unsigned char *addr, unsigned char *netmask,
void *data)
{
struct ethertap_data *pri = data;
if (pri->control_fd == -1)
return;
etap_close_addr(addr, netmask, &pri->control_fd);
}
const struct net_user_info ethertap_user_info = {
.init = etap_user_init,
.open = etap_open,
.close = etap_close,
.remove = NULL,
.add_address = etap_add_addr,
.delete_address = etap_del_addr,
.mtu = ETH_MAX_PACKET,
.max_packet = ETH_MAX_PACKET + ETH_HEADER_ETHERTAP,
};
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