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/*
*
* PPP library with GLib integration
*
* Copyright (C) 2009-2011 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <net/if.h>
#include <linux/if_tun.h>
#include <sys/ioctl.h>
#include <arpa/inet.h>
#include <glib.h>
#include "gatutil.h"
#include "gatppp.h"
#include "ppp.h"
#define MAX_PACKET 1500
struct ppp_net {
GAtPPP *ppp;
char *if_name;
GIOChannel *channel;
guint watch;
gint mtu;
struct ppp_header *ppp_packet;
};
gboolean ppp_net_set_mtu(struct ppp_net *net, guint16 mtu)
{
struct ifreq ifr;
int sk, err;
if (net == NULL || mtu > MAX_PACKET)
return FALSE;
net->mtu = mtu;
sk = socket(AF_INET, SOCK_DGRAM, 0);
if (sk < 0)
return FALSE;
memset(&ifr, 0, sizeof(ifr));
strncpy(ifr.ifr_name, net->if_name, sizeof(ifr.ifr_name));
ifr.ifr_mtu = mtu;
err = ioctl(sk, SIOCSIFMTU, (caddr_t) &ifr);
close(sk);
if (err < 0)
return FALSE;
return TRUE;
}
void ppp_net_process_packet(struct ppp_net *net, const guint8 *packet,
gsize plen)
{
GIOStatus status;
gsize bytes_written;
guint16 len;
if (plen < 4)
return;
/* find the length of the packet to transmit */
len = get_host_short(&packet[2]);
status = g_io_channel_write_chars(net->channel, (gchar *) packet,
MIN(len, plen),
&bytes_written, NULL);
if (status != G_IO_STATUS_NORMAL)
return;
}
/*
* packets received by the tun interface need to be written to
* the modem. So, just read a packet, write out to the modem
*/
static gboolean ppp_net_callback(GIOChannel *channel, GIOCondition cond,
gpointer userdata)
{
struct ppp_net *net = (struct ppp_net *) userdata;
GIOStatus status;
gsize bytes_read;
gchar *buf = (gchar *) net->ppp_packet->info;
if (cond & (G_IO_NVAL | G_IO_ERR | G_IO_HUP))
return FALSE;
if (cond & G_IO_IN) {
/* leave space to add PPP protocol field */
status = g_io_channel_read_chars(channel, buf, net->mtu,
&bytes_read, NULL);
if (bytes_read > 0)
ppp_transmit(net->ppp, (guint8 *) net->ppp_packet,
bytes_read);
if (status != G_IO_STATUS_NORMAL && status != G_IO_STATUS_AGAIN)
return FALSE;
}
return TRUE;
}
const char *ppp_net_get_interface(struct ppp_net *net)
{
return net->if_name;
}
struct ppp_net *ppp_net_new(GAtPPP *ppp, int fd)
{
struct ppp_net *net;
GIOChannel *channel = NULL;
struct ifreq ifr;
int err;
net = g_try_new0(struct ppp_net, 1);
if (net == NULL)
goto badalloc;
net->ppp_packet = ppp_packet_new(MAX_PACKET, PPP_IP_PROTO);
if (net->ppp_packet == NULL)
goto error;
/*
* If the fd value is still the default one,
* open the tun interface and configure it.
*/
memset(&ifr, 0, sizeof(ifr));
if (fd < 0) {
/* open a tun interface */
fd = open("/dev/net/tun", O_RDWR);
if (fd < 0)
goto error;
ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
strcpy(ifr.ifr_name, "ppp%d");
err = ioctl(fd, TUNSETIFF, (void *) &ifr);
if (err < 0)
goto error;
} else {
err = ioctl(fd, TUNGETIFF, (void *) &ifr);
if (err < 0)
goto error;
}
net->if_name = strdup(ifr.ifr_name);
/* create a channel for reading and writing to this interface */
channel = g_io_channel_unix_new(fd);
if (channel == NULL)
goto error;
if (!g_at_util_setup_io(channel, 0))
goto error;
g_io_channel_set_buffered(channel, FALSE);
net->channel = channel;
net->watch = g_io_add_watch(channel,
G_IO_IN | G_IO_HUP | G_IO_ERR | G_IO_NVAL,
ppp_net_callback, net);
net->ppp = ppp;
net->mtu = MAX_PACKET;
return net;
error:
if (channel)
g_io_channel_unref(channel);
g_free(net->if_name);
g_free(net->ppp_packet);
g_free(net);
badalloc:
if (fd >= 0)
close(fd);
return NULL;
}
void ppp_net_free(struct ppp_net *net)
{
if (net->watch) {
g_source_remove(net->watch);
net->watch = 0;
}
g_io_channel_unref(net->channel);
g_free(net->ppp_packet);
g_free(net->if_name);
g_free(net);
}
void ppp_net_suspend_interface(struct ppp_net *net)
{
if (net == NULL || net->channel == NULL)
return;
if (net->watch == 0)
return;
g_source_remove(net->watch);
net->watch = 0;
}
void ppp_net_resume_interface(struct ppp_net *net)
{
if (net == NULL || net->channel == NULL)
return;
net->watch = g_io_add_watch(net->channel,
G_IO_IN | G_IO_HUP | G_IO_ERR | G_IO_NVAL,
ppp_net_callback, net);
}
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