/*
* Copyright (C) 2016 David Decotigny <ddecotig@gmail.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* 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.
*/
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <linux_api.h>
#include <ipxe/list.h>
#include <ipxe/linux.h>
#include <ipxe/malloc.h>
#include <ipxe/device.h>
#include <ipxe/netdevice.h>
#include <ipxe/iobuf.h>
#include <ipxe/ethernet.h>
#include <ipxe/settings.h>
#include <ipxe/socket.h>
/* This hack prevents pre-2.6.32 headers from redefining struct sockaddr */
#define _SYS_SOCKET_H
#define __GLIBC__ 2
#include <linux/socket.h>
#include <linux/if.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
#undef __GLIBC__
#include <byteswap.h>
/* linux-specifc syscall params */
#define LINUX_AF_PACKET 17
#define LINUX_SOCK_RAW 3
#define LINUX_SIOCGIFINDEX 0x8933
#define LINUX_SIOCGIFHWADDR 0x8927
#define RX_BUF_SIZE 1536
/** @file
*
* The AF_PACKET driver.
*
* Bind to an existing linux network interface.
*/
struct af_packet_nic {
/** Linux network interface name */
char * ifname;
/** Packet socket descriptor */
int fd;
/** ifindex */
int ifindex;
};
/** Open the linux interface */
static int af_packet_nic_open ( struct net_device * netdev )
{
struct af_packet_nic * nic = netdev->priv;
struct sockaddr_ll socket_address;
struct ifreq if_data;
int ret;
nic->fd = linux_socket(LINUX_AF_PACKET, LINUX_SOCK_RAW,
htons(ETH_P_ALL));
if (nic->fd < 0) {
DBGC(nic, "af_packet %p socket(AF_PACKET) = %d (%s)\n",
nic, nic->fd, linux_strerror(linux_errno));
return nic->fd;
}
/* resolve ifindex of ifname */
memset(&if_data, 0, sizeof(if_data));
strncpy(if_data.ifr_name, nic->ifname, sizeof(if_data.ifr_name));
ret = linux_ioctl(nic->fd, LINUX_SIOCGIFINDEX, &if_data);
if (ret < 0) {
DBGC(nic, "af_packet %p ioctl(SIOCGIFINDEX) = %d (%s)\n",
nic, ret, linux_strerror(linux_errno));
linux_close(nic->fd);
return ret;
}
nic->ifindex = if_data.ifr_ifindex;
/* bind to interface */
memset(&socket_address, 0, sizeof(socket_address));
socket_address.sll_family = LINUX_AF_PACKET;
socket_address.sll_ifindex = nic->ifindex;
socket_address.sll_protocol = htons(ETH_P_ALL);
ret = linux_bind(nic->fd, (void *) &socket_address,
sizeof(socket_address));
if (ret == -1) {
DBGC(nic, "af_packet %p bind() = %d (%s)\n",
nic, ret, linux_strerror(linux_errno));
linux_close(nic->fd);
return ret;
}
/* Set nonblocking mode to make af_packet_nic_poll() easier */
ret = linux_fcntl(nic->fd, F_SETFL, O_NONBLOCK);
if (ret != 0) {
DBGC(nic, "af_packet %p fcntl(%d, ...) = %d (%s)\n",
nic, nic->fd, ret, linux_strerror(linux_errno));
linux_close(nic->fd);
return ret;
}
return 0;
}
/** Close the packet socket */
static void af_packet_nic_close ( struct net_device *netdev )
{
struct af_packet_nic * nic = netdev->priv;
linux_close(nic->fd);
}
/**
* Transmit an ethernet packet.
*
* The packet can be written to the socket and marked as complete immediately.
*/
static int af_packet_nic_transmit ( struct net_device *netdev,
struct io_buffer *iobuf )
{
struct af_packet_nic * nic = netdev->priv;
struct sockaddr_ll socket_address;
const struct ethhdr * eh;
int rc;
memset(&socket_address, 0, sizeof(socket_address));
socket_address.sll_family = LINUX_AF_PACKET;
socket_address.sll_ifindex = nic->ifindex;
socket_address.sll_halen = ETH_ALEN;
eh = iobuf->data;
memcpy(socket_address.sll_addr, eh->h_dest, ETH_ALEN);
rc = linux_sendto(nic->fd, iobuf->data, iobuf->tail - iobuf->data,
0, (struct sockaddr *)&socket_address,
sizeof(socket_address));
DBGC2(nic, "af_packet %p wrote %d bytes\n", nic, rc);
netdev_tx_complete(netdev, iobuf);
return 0;
}
/** Poll for new packets */
static void af_packet_nic_poll ( struct net_device *netdev )
{
struct af_packet_nic * nic = netdev->priv;
struct pollfd pfd;
struct io_buffer * iobuf;
int r;
pfd.fd = nic->fd;
pfd.events = POLLIN;
if (linux_poll(&pfd, 1, 0) == -1) {
DBGC(nic, "af_packet %p poll failed (%s)\n",
nic, linux_strerror(linux_errno));
return;
}
if ((pfd.revents & POLLIN) == 0)
return;
/* At this point we know there is at least one new packet to be read */
iobuf = alloc_iob(RX_BUF_SIZE);
if (! iobuf)
goto allocfail;
while ((r = linux_read(nic->fd, iobuf->data, RX_BUF_SIZE)) > 0) {
DBGC2(nic, "af_packet %p read %d bytes\n", nic, r);
iob_put(iobuf, r);
netdev_rx(netdev, iobuf);
iobuf = alloc_iob(RX_BUF_SIZE);
if (! iobuf)
goto allocfail;
}
free_iob(iobuf);
return;
allocfail:
DBGC(nic, "af_packet %p alloc_iob failed\n", nic);
}
/**
* Set irq.
*
* Not used on linux, provide a dummy implementation.
*/
static void af_packet_nic_irq ( struct net_device *netdev, int enable )
{
struct af_packet_nic *nic = netdev->priv;
DBGC(nic, "af_packet %p irq enable = %d\n", nic, enable);
}
static int af_packet_update_properties ( struct net_device *netdev )
{
struct af_packet_nic *nic = netdev->priv;
struct ifreq if_data;
int ret;
/* retrieve default MAC address */
int fd = linux_socket(LINUX_AF_PACKET, LINUX_SOCK_RAW, 0);
if (fd < 0) {
DBGC(nic, "af_packet %p cannot create raw socket (%s)\n",
nic, linux_strerror(linux_errno));
return fd;
}
/* retrieve host's MAC address */
memset(&if_data, 0, sizeof(if_data));
strncpy(if_data.ifr_name, nic->ifname, sizeof(if_data.ifr_name));
ret = linux_ioctl(fd, LINUX_SIOCGIFHWADDR, &if_data);
if (ret < 0) {
DBGC(nic, "af_packet %p cannot get mac addr (%s)\n",
nic, linux_strerror(linux_errno));
linux_close(fd);
return ret;
}
linux_close(fd);
/* struct sockaddr = { u16 family, u8 pad[14] (equiv. sa_data) }; */
memcpy(netdev->ll_addr, if_data.ifr_hwaddr.pad, ETH_ALEN);
return 0;
}
/** AF_PACKET operations */
static struct net_device_operations af_packet_nic_operations = {
.open = af_packet_nic_open,
.close = af_packet_nic_close,
.transmit = af_packet_nic_transmit,
.poll = af_packet_nic_poll,
.irq = af_packet_nic_irq,
};
/** Handle a device request for the af_packet driver */
static int af_packet_nic_probe ( struct linux_device *device,
struct linux_device_request *request )
{
struct linux_setting *if_setting;
struct net_device *netdev;
struct af_packet_nic *nic;
int rc;
netdev = alloc_etherdev(sizeof(*nic));
if (! netdev)
return -ENOMEM;
netdev_init(netdev, &af_packet_nic_operations);
nic = netdev->priv;
linux_set_drvdata(device, netdev);
netdev->dev = &device->dev;
memset(nic, 0, sizeof(*nic));
/* Look for the mandatory if setting */
if_setting = linux_find_setting("if", &request->settings);
/* No if setting */
if (! if_setting) {
printf("af_packet missing a mandatory if setting\n");
rc = -EINVAL;
goto err_settings;
}
nic->ifname = if_setting->value;
snprintf ( device->dev.name, sizeof ( device->dev.name ), "%s",
nic->ifname );
device->dev.desc.bus_type = BUS_TYPE_TAP;
af_packet_update_properties(netdev);
if_setting->applied = 1;
/* Apply rest of the settings */
linux_apply_settings(&request->settings, &netdev->settings.settings);
/* Register network device */
if ((rc = register_netdev(netdev)) != 0)
goto err_register;
netdev_link_up(netdev);
return 0;
err_settings:
unregister_netdev(netdev);
err_register:
netdev_nullify(netdev);
netdev_put(netdev);
return rc;
}
/** Remove the device */
static void af_packet_nic_remove ( struct linux_device *device )
{
struct net_device *netdev = linux_get_drvdata(device);
unregister_netdev(netdev);
netdev_nullify(netdev);
netdev_put(netdev);
}
/** AF_PACKET linux_driver */
struct linux_driver af_packet_nic_driver __linux_driver = {
.name = "af_packet",
.probe = af_packet_nic_probe,
.remove = af_packet_nic_remove,
.can_probe = 1,
};
