hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
linux-sg2042/drivers/net/wireless/virt_wifi.c

627 lines
16 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0
/* drivers/net/wireless/virt_wifi.c
*
* A fake implementation of cfg80211_ops that can be tacked on to an ethernet
* net_device to make it appear as a wireless connection.
*
* Copyright (C) 2018 Google, Inc.
*
* Author: schuffelen@google.com
*/
#include <net/cfg80211.h>
#include <net/rtnetlink.h>
#include <linux/etherdevice.h>
#include <linux/module.h>
static struct wiphy *common_wiphy;
struct virt_wifi_wiphy_priv {
struct delayed_work scan_result;
struct cfg80211_scan_request *scan_request;
bool being_deleted;
};
static struct ieee80211_channel channel_2ghz = {
.band = NL80211_BAND_2GHZ,
.center_freq = 2432,
.hw_value = 2432,
.max_power = 20,
};
static struct ieee80211_rate bitrates_2ghz[] = {
{ .bitrate = 10 },
{ .bitrate = 20 },
{ .bitrate = 55 },
{ .bitrate = 110 },
{ .bitrate = 60 },
{ .bitrate = 120 },
{ .bitrate = 240 },
};
static struct ieee80211_supported_band band_2ghz = {
.channels = &channel_2ghz,
.bitrates = bitrates_2ghz,
.band = NL80211_BAND_2GHZ,
.n_channels = 1,
.n_bitrates = ARRAY_SIZE(bitrates_2ghz),
.ht_cap = {
.ht_supported = true,
.cap = IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
IEEE80211_HT_CAP_GRN_FLD |
IEEE80211_HT_CAP_SGI_20 |
IEEE80211_HT_CAP_SGI_40 |
IEEE80211_HT_CAP_DSSSCCK40,
.ampdu_factor = 0x3,
.ampdu_density = 0x6,
.mcs = {
.rx_mask = {0xff, 0xff},
.tx_params = IEEE80211_HT_MCS_TX_DEFINED,
},
},
};
static struct ieee80211_channel channel_5ghz = {
.band = NL80211_BAND_5GHZ,
.center_freq = 5240,
.hw_value = 5240,
.max_power = 20,
};
static struct ieee80211_rate bitrates_5ghz[] = {
{ .bitrate = 60 },
{ .bitrate = 120 },
{ .bitrate = 240 },
};
#define RX_MCS_MAP (IEEE80211_VHT_MCS_SUPPORT_0_9 << 0 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 2 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 4 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 6 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 8 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 10 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 12 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 14)
#define TX_MCS_MAP (IEEE80211_VHT_MCS_SUPPORT_0_9 << 0 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 2 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 4 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 6 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 8 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 10 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 12 | \
IEEE80211_VHT_MCS_SUPPORT_0_9 << 14)
static struct ieee80211_supported_band band_5ghz = {
.channels = &channel_5ghz,
.bitrates = bitrates_5ghz,
.band = NL80211_BAND_5GHZ,
.n_channels = 1,
.n_bitrates = ARRAY_SIZE(bitrates_5ghz),
.ht_cap = {
.ht_supported = true,
.cap = IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
IEEE80211_HT_CAP_GRN_FLD |
IEEE80211_HT_CAP_SGI_20 |
IEEE80211_HT_CAP_SGI_40 |
IEEE80211_HT_CAP_DSSSCCK40,
.ampdu_factor = 0x3,
.ampdu_density = 0x6,
.mcs = {
.rx_mask = {0xff, 0xff},
.tx_params = IEEE80211_HT_MCS_TX_DEFINED,
},
},
.vht_cap = {
.vht_supported = true,
.cap = IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_11454 |
IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ |
IEEE80211_VHT_CAP_RXLDPC |
IEEE80211_VHT_CAP_SHORT_GI_80 |
IEEE80211_VHT_CAP_SHORT_GI_160 |
IEEE80211_VHT_CAP_TXSTBC |
IEEE80211_VHT_CAP_RXSTBC_1 |
IEEE80211_VHT_CAP_RXSTBC_2 |
IEEE80211_VHT_CAP_RXSTBC_3 |
IEEE80211_VHT_CAP_RXSTBC_4 |
IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK,
.vht_mcs = {
.rx_mcs_map = cpu_to_le16(RX_MCS_MAP),
.tx_mcs_map = cpu_to_le16(TX_MCS_MAP),
}
},
};
/* Assigned at module init. Guaranteed locally-administered and unicast. */
static u8 fake_router_bssid[ETH_ALEN] __ro_after_init = {};
/* Called with the rtnl lock held. */
static int virt_wifi_scan(struct wiphy *wiphy,
struct cfg80211_scan_request *request)
{
struct virt_wifi_wiphy_priv *priv = wiphy_priv(wiphy);
wiphy_debug(wiphy, "scan\n");
if (priv->scan_request || priv->being_deleted)
return -EBUSY;
priv->scan_request = request;
schedule_delayed_work(&priv->scan_result, HZ * 2);
return 0;
}
/* Acquires and releases the rdev BSS lock. */
static void virt_wifi_scan_result(struct work_struct *work)
{
struct {
u8 tag;
u8 len;
u8 ssid[8];
} __packed ssid = {
.tag = WLAN_EID_SSID, .len = 8, .ssid = "VirtWifi",
};
struct cfg80211_bss *informed_bss;
struct virt_wifi_wiphy_priv *priv =
container_of(work, struct virt_wifi_wiphy_priv,
scan_result.work);
struct wiphy *wiphy = priv_to_wiphy(priv);
struct cfg80211_scan_info scan_info = { .aborted = false };
informed_bss = cfg80211_inform_bss(wiphy, &channel_5ghz,
CFG80211_BSS_FTYPE_PRESP,
fake_router_bssid,
ktime_get_boot_ns(),
WLAN_CAPABILITY_ESS, 0,
(void *)&ssid, sizeof(ssid),
DBM_TO_MBM(-50), GFP_KERNEL);
cfg80211_put_bss(wiphy, informed_bss);
/* Schedules work which acquires and releases the rtnl lock. */
cfg80211_scan_done(priv->scan_request, &scan_info);
priv->scan_request = NULL;
}
/* May acquire and release the rdev BSS lock. */
static void virt_wifi_cancel_scan(struct wiphy *wiphy)
{
struct virt_wifi_wiphy_priv *priv = wiphy_priv(wiphy);
cancel_delayed_work_sync(&priv->scan_result);
/* Clean up dangling callbacks if necessary. */
if (priv->scan_request) {
struct cfg80211_scan_info scan_info = { .aborted = true };
/* Schedules work which acquires and releases the rtnl lock. */
cfg80211_scan_done(priv->scan_request, &scan_info);
priv->scan_request = NULL;
}
}
struct virt_wifi_netdev_priv {
struct delayed_work connect;
struct net_device *lowerdev;
struct net_device *upperdev;
u32 tx_packets;
u32 tx_failed;
u8 connect_requested_bss[ETH_ALEN];
bool is_up;
bool is_connected;
bool being_deleted;
};
/* Called with the rtnl lock held. */
static int virt_wifi_connect(struct wiphy *wiphy, struct net_device *netdev,
struct cfg80211_connect_params *sme)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(netdev);
bool could_schedule;
if (priv->being_deleted || !priv->is_up)
return -EBUSY;
could_schedule = schedule_delayed_work(&priv->connect, HZ * 2);
if (!could_schedule)
return -EBUSY;
if (sme->bssid)
ether_addr_copy(priv->connect_requested_bss, sme->bssid);
else
eth_zero_addr(priv->connect_requested_bss);
wiphy_debug(wiphy, "connect\n");
return 0;
}
/* Acquires and releases the rdev event lock. */
static void virt_wifi_connect_complete(struct work_struct *work)
{
struct virt_wifi_netdev_priv *priv =
container_of(work, struct virt_wifi_netdev_priv, connect.work);
u8 *requested_bss = priv->connect_requested_bss;
bool has_addr = !is_zero_ether_addr(requested_bss);
bool right_addr = ether_addr_equal(requested_bss, fake_router_bssid);
u16 status = WLAN_STATUS_SUCCESS;
if (!priv->is_up || (has_addr && !right_addr))
status = WLAN_STATUS_UNSPECIFIED_FAILURE;
else
priv->is_connected = true;
/* Schedules an event that acquires the rtnl lock. */
cfg80211_connect_result(priv->upperdev, requested_bss, NULL, 0, NULL, 0,
status, GFP_KERNEL);
netif_carrier_on(priv->upperdev);
}
/* May acquire and release the rdev event lock. */
static void virt_wifi_cancel_connect(struct net_device *netdev)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(netdev);
/* If there is work pending, clean up dangling callbacks. */
if (cancel_delayed_work_sync(&priv->connect)) {
/* Schedules an event that acquires the rtnl lock. */
cfg80211_connect_result(priv->upperdev,
priv->connect_requested_bss, NULL, 0,
NULL, 0,
WLAN_STATUS_UNSPECIFIED_FAILURE,
GFP_KERNEL);
}
}
/* Called with the rtnl lock held. Acquires the rdev event lock. */
static int virt_wifi_disconnect(struct wiphy *wiphy, struct net_device *netdev,
u16 reason_code)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(netdev);
if (priv->being_deleted)
return -EBUSY;
wiphy_debug(wiphy, "disconnect\n");
virt_wifi_cancel_connect(netdev);
cfg80211_disconnected(netdev, reason_code, NULL, 0, true, GFP_KERNEL);
priv->is_connected = false;
netif_carrier_off(netdev);
return 0;
}
/* Called with the rtnl lock held. */
static int virt_wifi_get_station(struct wiphy *wiphy, struct net_device *dev,
const u8 *mac, struct station_info *sinfo)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
wiphy_debug(wiphy, "get_station\n");
if (!priv->is_connected || !ether_addr_equal(mac, fake_router_bssid))
return -ENOENT;
sinfo->filled = BIT_ULL(NL80211_STA_INFO_TX_PACKETS) |
BIT_ULL(NL80211_STA_INFO_TX_FAILED) |
BIT_ULL(NL80211_STA_INFO_SIGNAL) |
BIT_ULL(NL80211_STA_INFO_TX_BITRATE);
sinfo->tx_packets = priv->tx_packets;
sinfo->tx_failed = priv->tx_failed;
/* For CFG80211_SIGNAL_TYPE_MBM, value is expressed in _dBm_ */
sinfo->signal = -50;
sinfo->txrate = (struct rate_info) {
.legacy = 10, /* units are 100kbit/s */
};
return 0;
}
/* Called with the rtnl lock held. */
static int virt_wifi_dump_station(struct wiphy *wiphy, struct net_device *dev,
int idx, u8 *mac, struct station_info *sinfo)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
wiphy_debug(wiphy, "dump_station\n");
if (idx != 0 || !priv->is_connected)
return -ENOENT;
ether_addr_copy(mac, fake_router_bssid);
return virt_wifi_get_station(wiphy, dev, fake_router_bssid, sinfo);
}
static const struct cfg80211_ops virt_wifi_cfg80211_ops = {
.scan = virt_wifi_scan,
.connect = virt_wifi_connect,
.disconnect = virt_wifi_disconnect,
.get_station = virt_wifi_get_station,
.dump_station = virt_wifi_dump_station,
};
/* Acquires and releases the rtnl lock. */
static struct wiphy *virt_wifi_make_wiphy(void)
{
struct wiphy *wiphy;
struct virt_wifi_wiphy_priv *priv;
int err;
wiphy = wiphy_new(&virt_wifi_cfg80211_ops, sizeof(*priv));
if (!wiphy)
return NULL;
wiphy->max_scan_ssids = 4;
wiphy->max_scan_ie_len = 1000;
wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
wiphy->bands[NL80211_BAND_2GHZ] = &band_2ghz;
wiphy->bands[NL80211_BAND_5GHZ] = &band_5ghz;
wiphy->bands[NL80211_BAND_60GHZ] = NULL;
wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
priv = wiphy_priv(wiphy);
priv->being_deleted = false;
priv->scan_request = NULL;
INIT_DELAYED_WORK(&priv->scan_result, virt_wifi_scan_result);
err = wiphy_register(wiphy);
if (err < 0) {
wiphy_free(wiphy);
return NULL;
}
return wiphy;
}
/* Acquires and releases the rtnl lock. */
static void virt_wifi_destroy_wiphy(struct wiphy *wiphy)
{
struct virt_wifi_wiphy_priv *priv;
WARN(!wiphy, "%s called with null wiphy", __func__);
if (!wiphy)
return;
priv = wiphy_priv(wiphy);
priv->being_deleted = true;
virt_wifi_cancel_scan(wiphy);
if (wiphy->registered)
wiphy_unregister(wiphy);
wiphy_free(wiphy);
}
/* Enters and exits a RCU-bh critical section. */
static netdev_tx_t virt_wifi_start_xmit(struct sk_buff *skb,
struct net_device *dev)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
priv->tx_packets++;
if (!priv->is_connected) {
priv->tx_failed++;
return NET_XMIT_DROP;
}
skb->dev = priv->lowerdev;
return dev_queue_xmit(skb);
}
/* Called with rtnl lock held. */
static int virt_wifi_net_device_open(struct net_device *dev)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
priv->is_up = true;
return 0;
}
/* Called with rtnl lock held. */
static int virt_wifi_net_device_stop(struct net_device *dev)
{
struct virt_wifi_netdev_priv *n_priv = netdev_priv(dev);
n_priv->is_up = false;
if (!dev->ieee80211_ptr)
return 0;
virt_wifi_cancel_scan(dev->ieee80211_ptr->wiphy);
virt_wifi_cancel_connect(dev);
netif_carrier_off(dev);
return 0;
}
static const struct net_device_ops virt_wifi_ops = {
.ndo_start_xmit = virt_wifi_start_xmit,
.ndo_open = virt_wifi_net_device_open,
.ndo_stop = virt_wifi_net_device_stop,
};
/* Invoked as part of rtnl lock release. */
static void virt_wifi_net_device_destructor(struct net_device *dev)
{
/* Delayed past dellink to allow nl80211 to react to the device being
* deleted.
*/
kfree(dev->ieee80211_ptr);
dev->ieee80211_ptr = NULL;
free_netdev(dev);
}
/* No lock interaction. */
static void virt_wifi_setup(struct net_device *dev)
{
ether_setup(dev);
dev->netdev_ops = &virt_wifi_ops;
dev->priv_destructor = virt_wifi_net_device_destructor;
}
/* Called in a RCU read critical section from netif_receive_skb */
static rx_handler_result_t virt_wifi_rx_handler(struct sk_buff **pskb)
{
struct sk_buff *skb = *pskb;
struct virt_wifi_netdev_priv *priv =
rcu_dereference(skb->dev->rx_handler_data);
if (!priv->is_connected)
return RX_HANDLER_PASS;
/* GFP_ATOMIC because this is a packet interrupt handler. */
skb = skb_share_check(skb, GFP_ATOMIC);
if (!skb) {
dev_err(&priv->upperdev->dev, "can't skb_share_check\n");
return RX_HANDLER_CONSUMED;
}
*pskb = skb;
skb->dev = priv->upperdev;
skb->pkt_type = PACKET_HOST;
return RX_HANDLER_ANOTHER;
}
/* Called with rtnl lock held. */
static int virt_wifi_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
int err;
if (!tb[IFLA_LINK])
return -EINVAL;
netif_carrier_off(dev);
priv->upperdev = dev;
priv->lowerdev = __dev_get_by_index(src_net,
nla_get_u32(tb[IFLA_LINK]));
if (!priv->lowerdev)
return -ENODEV;
if (!tb[IFLA_MTU])
dev->mtu = priv->lowerdev->mtu;
else if (dev->mtu > priv->lowerdev->mtu)
return -EINVAL;
err = netdev_rx_handler_register(priv->lowerdev, virt_wifi_rx_handler,
priv);
if (err) {
dev_err(&priv->lowerdev->dev,
"can't netdev_rx_handler_register: %d\n", err);
return err;
}
eth_hw_addr_inherit(dev, priv->lowerdev);
netif_stacked_transfer_operstate(priv->lowerdev, dev);
SET_NETDEV_DEV(dev, &priv->lowerdev->dev);
dev->ieee80211_ptr = kzalloc(sizeof(*dev->ieee80211_ptr), GFP_KERNEL);
if (!dev->ieee80211_ptr) {
err = -ENOMEM;
goto remove_handler;
}
dev->ieee80211_ptr->iftype = NL80211_IFTYPE_STATION;
dev->ieee80211_ptr->wiphy = common_wiphy;
err = register_netdevice(dev);
if (err) {
dev_err(&priv->lowerdev->dev, "can't register_netdevice: %d\n",
err);
goto free_wireless_dev;
}
err = netdev_upper_dev_link(priv->lowerdev, dev, extack);
if (err) {
dev_err(&priv->lowerdev->dev, "can't netdev_upper_dev_link: %d\n",
err);
goto unregister_netdev;
}
priv->being_deleted = false;
priv->is_connected = false;
priv->is_up = false;
INIT_DELAYED_WORK(&priv->connect, virt_wifi_connect_complete);
return 0;
unregister_netdev:
unregister_netdevice(dev);
free_wireless_dev:
kfree(dev->ieee80211_ptr);
dev->ieee80211_ptr = NULL;
remove_handler:
netdev_rx_handler_unregister(priv->lowerdev);
return err;
}
/* Called with rtnl lock held. */
static void virt_wifi_dellink(struct net_device *dev,
struct list_head *head)
{
struct virt_wifi_netdev_priv *priv = netdev_priv(dev);
if (dev->ieee80211_ptr)
virt_wifi_cancel_scan(dev->ieee80211_ptr->wiphy);
priv->being_deleted = true;
virt_wifi_cancel_connect(dev);
netif_carrier_off(dev);
netdev_rx_handler_unregister(priv->lowerdev);
netdev_upper_dev_unlink(priv->lowerdev, dev);
unregister_netdevice_queue(dev, head);
/* Deleting the wiphy is handled in the module destructor. */
}
static struct rtnl_link_ops virt_wifi_link_ops = {
.kind = "virt_wifi",
.setup = virt_wifi_setup,
.newlink = virt_wifi_newlink,
.dellink = virt_wifi_dellink,
.priv_size = sizeof(struct virt_wifi_netdev_priv),
};
/* Acquires and releases the rtnl lock. */
static int __init virt_wifi_init_module(void)
{
int err;
/* Guaranteed to be locallly-administered and not multicast. */
eth_random_addr(fake_router_bssid);
common_wiphy = virt_wifi_make_wiphy();
if (!common_wiphy)
return -ENOMEM;
err = rtnl_link_register(&virt_wifi_link_ops);
if (err)
virt_wifi_destroy_wiphy(common_wiphy);
return err;
}
/* Acquires and releases the rtnl lock. */
static void __exit virt_wifi_cleanup_module(void)
{
/* Will delete any devices that depend on the wiphy. */
rtnl_link_unregister(&virt_wifi_link_ops);
virt_wifi_destroy_wiphy(common_wiphy);
}
module_init(virt_wifi_init_module);
module_exit(virt_wifi_cleanup_module);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Cody Schuffelen <schuffelen@google.com>");
MODULE_DESCRIPTION("Driver for a wireless wrapper of ethernet devices");
MODULE_ALIAS_RTNL_LINK("virt_wifi");
Reference in New Issue View Git Blame Copy Permalink