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/*
* Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <stdio.h>
#include <unistd.h>
#include <stdarg.h>
#include <errno.h>
#include <stddef.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include "net_user.h"
#include "kern_constants.h"
#include "os.h"
#include "um_malloc.h"
#include "user.h"
int tap_open_common(void *dev, char *gate_addr)
{
int tap_addr[4];
if (gate_addr == NULL)
return 0;
if (sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0],
&tap_addr[1], &tap_addr[2], &tap_addr[3]) != 4) {
printk(UM_KERN_ERR "Invalid tap IP address - '%s'\n",
gate_addr);
return -EINVAL;
}
return 0;
}
void tap_check_ips(char *gate_addr, unsigned char *eth_addr)
{
int tap_addr[4];
if ((gate_addr != NULL) &&
(sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0],
&tap_addr[1], &tap_addr[2], &tap_addr[3]) == 4) &&
(eth_addr[0] == tap_addr[0]) &&
(eth_addr[1] == tap_addr[1]) &&
(eth_addr[2] == tap_addr[2]) &&
(eth_addr[3] == tap_addr[3])) {
printk(UM_KERN_ERR "The tap IP address and the UML eth IP "
"address must be different\n");
}
}
/* Do reliable error handling as this fails frequently enough. */
void read_output(int fd, char *output, int len)
{
int remain, ret, expected;
char c;
char *str;
if (output == NULL) {
output = &c;
len = sizeof(c);
}
*output = '\0';
ret = read(fd, &remain, sizeof(remain));
if (ret != sizeof(remain)) {
if (ret < 0)
ret = -errno;
expected = sizeof(remain);
str = "length";
goto err;
}
while (remain != 0) {
expected = (remain < len) ? remain : len;
ret = read(fd, output, expected);
if (ret != expected) {
if (ret < 0)
ret = -errno;
str = "data";
goto err;
}
remain -= ret;
}
return;
err:
if (ret < 0)
printk(UM_KERN_ERR "read_output - read of %s failed, "
"errno = %d\n", str, -ret);
else
printk(UM_KERN_ERR "read_output - read of %s failed, read only "
"%d of %d bytes\n", str, ret, expected);
}
int net_read(int fd, void *buf, int len)
{
int n;
n = read(fd, buf, len);
if ((n < 0) && (errno == EAGAIN))
return 0;
else if (n == 0)
return -ENOTCONN;
return n;
}
int net_recvfrom(int fd, void *buf, int len)
{
int n;
CATCH_EINTR(n = recvfrom(fd, buf, len, 0, NULL, NULL));
if (n < 0) {
if (errno == EAGAIN)
return 0;
return -errno;
}
else if (n == 0)
return -ENOTCONN;
return n;
}
int net_write(int fd, void *buf, int len)
{
int n;
n = write(fd, buf, len);
if ((n < 0) && (errno == EAGAIN))
return 0;
else if (n == 0)
return -ENOTCONN;
return n;
}
int net_send(int fd, void *buf, int len)
{
int n;
CATCH_EINTR(n = send(fd, buf, len, 0));
if (n < 0) {
if (errno == EAGAIN)
return 0;
return -errno;
}
else if (n == 0)
return -ENOTCONN;
return n;
}
int net_sendto(int fd, void *buf, int len, void *to, int sock_len)
{
int n;
CATCH_EINTR(n = sendto(fd, buf, len, 0, (struct sockaddr *) to,
sock_len));
if (n < 0) {
if (errno == EAGAIN)
return 0;
return -errno;
}
else if (n == 0)
return -ENOTCONN;
return n;
}
struct change_pre_exec_data {
int close_me;
int stdout;
};
static void change_pre_exec(void *arg)
{
struct change_pre_exec_data *data = arg;
close(data->close_me);
dup2(data->stdout, 1);
}
static int change_tramp(char **argv, char *output, int output_len)
{
int pid, fds[2], err;
struct change_pre_exec_data pe_data;
err = os_pipe(fds, 1, 0);
if (err < 0) {
printk(UM_KERN_ERR "change_tramp - pipe failed, err = %d\n",
-err);
return err;
}
pe_data.close_me = fds[0];
pe_data.stdout = fds[1];
pid = run_helper(change_pre_exec, &pe_data, argv);
if (pid > 0) /* Avoid hang as we won't get data in failure case. */
read_output(fds[0], output, output_len);
close(fds[0]);
close(fds[1]);
if (pid > 0)
CATCH_EINTR(err = waitpid(pid, NULL, 0));
return pid;
}
static void change(char *dev, char *what, unsigned char *addr,
unsigned char *netmask)
{
char addr_buf[sizeof("255.255.255.255\0")];
char netmask_buf[sizeof("255.255.255.255\0")];
char version[sizeof("nnnnn\0")];
char *argv[] = { "uml_net", version, what, dev, addr_buf,
netmask_buf, NULL };
char *output;
int output_len, pid;
sprintf(version, "%d", UML_NET_VERSION);
sprintf(addr_buf, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
sprintf(netmask_buf, "%d.%d.%d.%d", netmask[0], netmask[1],
netmask[2], netmask[3]);
output_len = UM_KERN_PAGE_SIZE;
output = kmalloc(output_len, UM_GFP_KERNEL);
if (output == NULL)
printk(UM_KERN_ERR "change : failed to allocate output "
"buffer\n");
pid = change_tramp(argv, output, output_len);
if (pid < 0) return;
if (output != NULL) {
printk("%s", output);
kfree(output);
}
}
void open_addr(unsigned char *addr, unsigned char *netmask, void *arg)
{
change(arg, "add", addr, netmask);
}
void close_addr(unsigned char *addr, unsigned char *netmask, void *arg)
{
change(arg, "del", addr, netmask);
}
char *split_if_spec(char *str, ...)
{
char **arg, *end;
va_list ap;
va_start(ap, str);
while ((arg = va_arg(ap, char **)) != NULL) {
if (*str == '\0')
return NULL;
end = strchr(str, ',');
if (end != str)
*arg = str;
if (end == NULL)
return NULL;
*end++ = '\0';
str = end;
}
va_end(ap);
return str;
}
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