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/*
* user-mode-linux networking multicast transport
* Copyright (C) 2001 by Harald Welte <laforge@gnumonks.org>
*
* based on the existing uml-networking code, which is
* 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 <errno.h>
#include <unistd.h>
#include <linux/inet.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/time.h>
#include <netinet/in.h>
#include "net_user.h"
#include "mcast.h"
#include "kern_util.h"
#include "user_util.h"
#include "user.h"
#include "os.h"
#define MAX_PACKET (ETH_MAX_PACKET + ETH_HEADER_OTHER)
static struct sockaddr_in *new_addr(char *addr, unsigned short port)
{
struct sockaddr_in *sin;
sin = um_kmalloc(sizeof(struct sockaddr_in));
if(sin == NULL){
printk("new_addr: allocation of sockaddr_in failed\n");
return(NULL);
}
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = in_aton(addr);
sin->sin_port = htons(port);
return(sin);
}
static void mcast_user_init(void *data, void *dev)
{
struct mcast_data *pri = data;
pri->mcast_addr = new_addr(pri->addr, pri->port);
pri->dev = dev;
}
static int mcast_open(void *data)
{
struct mcast_data *pri = data;
struct sockaddr_in *sin = pri->mcast_addr;
struct ip_mreq mreq;
int fd = -EINVAL, yes = 1, err = -EINVAL;;
if ((sin->sin_addr.s_addr == 0) || (sin->sin_port == 0))
goto out;
fd = socket(AF_INET, SOCK_DGRAM, 0);
if (fd < 0){
printk("mcast_open : data socket failed, errno = %d\n",
errno);
fd = -errno;
goto out;
}
if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) {
printk("mcast_open: SO_REUSEADDR failed, errno = %d\n",
errno);
goto out_close;
}
/* set ttl according to config */
if (setsockopt(fd, SOL_IP, IP_MULTICAST_TTL, &pri->ttl,
sizeof(pri->ttl)) < 0) {
printk("mcast_open: IP_MULTICAST_TTL failed, error = %d\n",
errno);
goto out_close;
}
/* set LOOP, so data does get fed back to local sockets */
if (setsockopt(fd, SOL_IP, IP_MULTICAST_LOOP, &yes, sizeof(yes)) < 0) {
printk("mcast_open: IP_MULTICAST_LOOP failed, error = %d\n",
errno);
goto out_close;
}
/* bind socket to mcast address */
if (bind(fd, (struct sockaddr *) sin, sizeof(*sin)) < 0) {
printk("mcast_open : data bind failed, errno = %d\n", errno);
goto out_close;
}
/* subscribe to the multicast group */
mreq.imr_multiaddr.s_addr = sin->sin_addr.s_addr;
mreq.imr_interface.s_addr = 0;
if (setsockopt(fd, SOL_IP, IP_ADD_MEMBERSHIP,
&mreq, sizeof(mreq)) < 0) {
printk("mcast_open: IP_ADD_MEMBERSHIP failed, error = %d\n",
errno);
printk("There appears not to be a multicast-capable network "
"interface on the host.\n");
printk("eth0 should be configured in order to use the "
"multicast transport.\n");
goto out_close;
}
out:
return fd;
out_close:
os_close_file(fd);
return err;
}
static void mcast_close(int fd, void *data)
{
struct ip_mreq mreq;
struct mcast_data *pri = data;
struct sockaddr_in *sin = pri->mcast_addr;
mreq.imr_multiaddr.s_addr = sin->sin_addr.s_addr;
mreq.imr_interface.s_addr = 0;
if (setsockopt(fd, SOL_IP, IP_DROP_MEMBERSHIP,
&mreq, sizeof(mreq)) < 0) {
printk("mcast_open: IP_DROP_MEMBERSHIP failed, error = %d\n",
errno);
}
os_close_file(fd);
}
int mcast_user_write(int fd, void *buf, int len, struct mcast_data *pri)
{
struct sockaddr_in *data_addr = pri->mcast_addr;
return(net_sendto(fd, buf, len, data_addr, sizeof(*data_addr)));
}
static int mcast_set_mtu(int mtu, void *data)
{
return(mtu);
}
struct net_user_info mcast_user_info = {
.init = mcast_user_init,
.open = mcast_open,
.close = mcast_close,
.remove = NULL,
.set_mtu = mcast_set_mtu,
.add_address = NULL,
.delete_address = NULL,
.max_packet = MAX_PACKET - ETH_HEADER_OTHER
};
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