linux/net/mac802154/iface.c
Colin Ian King 0f77f2defa ieee802154: Remove redundant initialization of variable ret
The variable ret is being initialized with a value that is never read, it
is being updated later on. The assignment is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-07 14:06:08 +01:00

744 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2007-2012 Siemens AG
*
* Written by:
* Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
* Sergey Lapin <slapin@ossfans.org>
* Maxim Gorbachyov <maxim.gorbachev@siemens.com>
* Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
*/
#include <linux/netdevice.h>
#include <linux/module.h>
#include <linux/if_arp.h>
#include <linux/ieee802154.h>
#include <net/nl802154.h>
#include <net/mac802154.h>
#include <net/ieee802154_netdev.h>
#include <net/cfg802154.h>
#include "ieee802154_i.h"
#include "driver-ops.h"
int mac802154_wpan_update_llsec(struct net_device *dev)
{
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
struct ieee802154_mlme_ops *ops = ieee802154_mlme_ops(dev);
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
int rc = 0;
if (ops->llsec) {
struct ieee802154_llsec_params params;
int changed = 0;
params.pan_id = wpan_dev->pan_id;
changed |= IEEE802154_LLSEC_PARAM_PAN_ID;
params.hwaddr = wpan_dev->extended_addr;
changed |= IEEE802154_LLSEC_PARAM_HWADDR;
rc = ops->llsec->set_params(dev, &params, changed);
}
return rc;
}
static int
mac802154_wpan_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
struct sockaddr_ieee802154 *sa =
(struct sockaddr_ieee802154 *)&ifr->ifr_addr;
int err = -ENOIOCTLCMD;
if (cmd != SIOCGIFADDR && cmd != SIOCSIFADDR)
return err;
rtnl_lock();
switch (cmd) {
case SIOCGIFADDR:
{
u16 pan_id, short_addr;
pan_id = le16_to_cpu(wpan_dev->pan_id);
short_addr = le16_to_cpu(wpan_dev->short_addr);
if (pan_id == IEEE802154_PANID_BROADCAST ||
short_addr == IEEE802154_ADDR_BROADCAST) {
err = -EADDRNOTAVAIL;
break;
}
sa->family = AF_IEEE802154;
sa->addr.addr_type = IEEE802154_ADDR_SHORT;
sa->addr.pan_id = pan_id;
sa->addr.short_addr = short_addr;
err = 0;
break;
}
case SIOCSIFADDR:
if (netif_running(dev)) {
rtnl_unlock();
return -EBUSY;
}
dev_warn(&dev->dev,
"Using DEBUGing ioctl SIOCSIFADDR isn't recommended!\n");
if (sa->family != AF_IEEE802154 ||
sa->addr.addr_type != IEEE802154_ADDR_SHORT ||
sa->addr.pan_id == IEEE802154_PANID_BROADCAST ||
sa->addr.short_addr == IEEE802154_ADDR_BROADCAST ||
sa->addr.short_addr == IEEE802154_ADDR_UNDEF) {
err = -EINVAL;
break;
}
wpan_dev->pan_id = cpu_to_le16(sa->addr.pan_id);
wpan_dev->short_addr = cpu_to_le16(sa->addr.short_addr);
err = mac802154_wpan_update_llsec(dev);
break;
}
rtnl_unlock();
return err;
}
static int mac802154_wpan_mac_addr(struct net_device *dev, void *p)
{
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
struct sockaddr *addr = p;
__le64 extended_addr;
if (netif_running(dev))
return -EBUSY;
/* lowpan need to be down for update
* SLAAC address after ifup
*/
if (sdata->wpan_dev.lowpan_dev) {
if (netif_running(sdata->wpan_dev.lowpan_dev))
return -EBUSY;
}
ieee802154_be64_to_le64(&extended_addr, addr->sa_data);
if (!ieee802154_is_valid_extended_unicast_addr(extended_addr))
return -EINVAL;
memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
sdata->wpan_dev.extended_addr = extended_addr;
/* update lowpan interface mac address when
* wpan mac has been changed
*/
if (sdata->wpan_dev.lowpan_dev)
memcpy(sdata->wpan_dev.lowpan_dev->dev_addr, dev->dev_addr,
dev->addr_len);
return mac802154_wpan_update_llsec(dev);
}
static int ieee802154_setup_hw(struct ieee802154_sub_if_data *sdata)
{
struct ieee802154_local *local = sdata->local;
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
int ret;
if (local->hw.flags & IEEE802154_HW_PROMISCUOUS) {
ret = drv_set_promiscuous_mode(local,
wpan_dev->promiscuous_mode);
if (ret < 0)
return ret;
}
if (local->hw.flags & IEEE802154_HW_AFILT) {
ret = drv_set_pan_id(local, wpan_dev->pan_id);
if (ret < 0)
return ret;
ret = drv_set_extended_addr(local, wpan_dev->extended_addr);
if (ret < 0)
return ret;
ret = drv_set_short_addr(local, wpan_dev->short_addr);
if (ret < 0)
return ret;
}
if (local->hw.flags & IEEE802154_HW_LBT) {
ret = drv_set_lbt_mode(local, wpan_dev->lbt);
if (ret < 0)
return ret;
}
if (local->hw.flags & IEEE802154_HW_CSMA_PARAMS) {
ret = drv_set_csma_params(local, wpan_dev->min_be,
wpan_dev->max_be,
wpan_dev->csma_retries);
if (ret < 0)
return ret;
}
if (local->hw.flags & IEEE802154_HW_FRAME_RETRIES) {
ret = drv_set_max_frame_retries(local, wpan_dev->frame_retries);
if (ret < 0)
return ret;
}
return 0;
}
static int mac802154_slave_open(struct net_device *dev)
{
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
struct ieee802154_local *local = sdata->local;
int res;
ASSERT_RTNL();
set_bit(SDATA_STATE_RUNNING, &sdata->state);
if (!local->open_count) {
res = ieee802154_setup_hw(sdata);
if (res)
goto err;
res = drv_start(local);
if (res)
goto err;
}
local->open_count++;
netif_start_queue(dev);
return 0;
err:
/* might already be clear but that doesn't matter */
clear_bit(SDATA_STATE_RUNNING, &sdata->state);
return res;
}
static int
ieee802154_check_mac_settings(struct ieee802154_local *local,
struct wpan_dev *wpan_dev,
struct wpan_dev *nwpan_dev)
{
ASSERT_RTNL();
if (local->hw.flags & IEEE802154_HW_PROMISCUOUS) {
if (wpan_dev->promiscuous_mode != nwpan_dev->promiscuous_mode)
return -EBUSY;
}
if (local->hw.flags & IEEE802154_HW_AFILT) {
if (wpan_dev->pan_id != nwpan_dev->pan_id ||
wpan_dev->short_addr != nwpan_dev->short_addr ||
wpan_dev->extended_addr != nwpan_dev->extended_addr)
return -EBUSY;
}
if (local->hw.flags & IEEE802154_HW_CSMA_PARAMS) {
if (wpan_dev->min_be != nwpan_dev->min_be ||
wpan_dev->max_be != nwpan_dev->max_be ||
wpan_dev->csma_retries != nwpan_dev->csma_retries)
return -EBUSY;
}
if (local->hw.flags & IEEE802154_HW_FRAME_RETRIES) {
if (wpan_dev->frame_retries != nwpan_dev->frame_retries)
return -EBUSY;
}
if (local->hw.flags & IEEE802154_HW_LBT) {
if (wpan_dev->lbt != nwpan_dev->lbt)
return -EBUSY;
}
return 0;
}
static int
ieee802154_check_concurrent_iface(struct ieee802154_sub_if_data *sdata,
enum nl802154_iftype iftype)
{
struct ieee802154_local *local = sdata->local;
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
struct ieee802154_sub_if_data *nsdata;
/* we hold the RTNL here so can safely walk the list */
list_for_each_entry(nsdata, &local->interfaces, list) {
if (nsdata != sdata && ieee802154_sdata_running(nsdata)) {
int ret;
/* TODO currently we don't support multiple node types
* we need to run skb_clone at rx path. Check if there
* exist really an use case if we need to support
* multiple node types at the same time.
*/
if (wpan_dev->iftype == NL802154_IFTYPE_NODE &&
nsdata->wpan_dev.iftype == NL802154_IFTYPE_NODE)
return -EBUSY;
/* check all phy mac sublayer settings are the same.
* We have only one phy, different values makes trouble.
*/
ret = ieee802154_check_mac_settings(local, wpan_dev,
&nsdata->wpan_dev);
if (ret < 0)
return ret;
}
}
return 0;
}
static int mac802154_wpan_open(struct net_device *dev)
{
int rc;
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
rc = ieee802154_check_concurrent_iface(sdata, wpan_dev->iftype);
if (rc < 0)
return rc;
return mac802154_slave_open(dev);
}
static int mac802154_slave_close(struct net_device *dev)
{
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
struct ieee802154_local *local = sdata->local;
ASSERT_RTNL();
netif_stop_queue(dev);
local->open_count--;
clear_bit(SDATA_STATE_RUNNING, &sdata->state);
if (!local->open_count)
ieee802154_stop_device(local);
return 0;
}
static int mac802154_set_header_security(struct ieee802154_sub_if_data *sdata,
struct ieee802154_hdr *hdr,
const struct ieee802154_mac_cb *cb)
{
struct ieee802154_llsec_params params;
u8 level;
mac802154_llsec_get_params(&sdata->sec, &params);
if (!params.enabled && cb->secen_override && cb->secen)
return -EINVAL;
if (!params.enabled ||
(cb->secen_override && !cb->secen) ||
!params.out_level)
return 0;
if (cb->seclevel_override && !cb->seclevel)
return -EINVAL;
level = cb->seclevel_override ? cb->seclevel : params.out_level;
hdr->fc.security_enabled = 1;
hdr->sec.level = level;
hdr->sec.key_id_mode = params.out_key.mode;
if (params.out_key.mode == IEEE802154_SCF_KEY_SHORT_INDEX)
hdr->sec.short_src = params.out_key.short_source;
else if (params.out_key.mode == IEEE802154_SCF_KEY_HW_INDEX)
hdr->sec.extended_src = params.out_key.extended_source;
hdr->sec.key_id = params.out_key.id;
return 0;
}
static int ieee802154_header_create(struct sk_buff *skb,
struct net_device *dev,
const struct ieee802154_addr *daddr,
const struct ieee802154_addr *saddr,
unsigned len)
{
struct ieee802154_hdr hdr;
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
struct ieee802154_mac_cb *cb = mac_cb(skb);
int hlen;
if (!daddr)
return -EINVAL;
memset(&hdr.fc, 0, sizeof(hdr.fc));
hdr.fc.type = cb->type;
hdr.fc.security_enabled = cb->secen;
hdr.fc.ack_request = cb->ackreq;
hdr.seq = atomic_inc_return(&dev->ieee802154_ptr->dsn) & 0xFF;
if (mac802154_set_header_security(sdata, &hdr, cb) < 0)
return -EINVAL;
if (!saddr) {
if (wpan_dev->short_addr == cpu_to_le16(IEEE802154_ADDR_BROADCAST) ||
wpan_dev->short_addr == cpu_to_le16(IEEE802154_ADDR_UNDEF) ||
wpan_dev->pan_id == cpu_to_le16(IEEE802154_PANID_BROADCAST)) {
hdr.source.mode = IEEE802154_ADDR_LONG;
hdr.source.extended_addr = wpan_dev->extended_addr;
} else {
hdr.source.mode = IEEE802154_ADDR_SHORT;
hdr.source.short_addr = wpan_dev->short_addr;
}
hdr.source.pan_id = wpan_dev->pan_id;
} else {
hdr.source = *(const struct ieee802154_addr *)saddr;
}
hdr.dest = *(const struct ieee802154_addr *)daddr;
hlen = ieee802154_hdr_push(skb, &hdr);
if (hlen < 0)
return -EINVAL;
skb_reset_mac_header(skb);
skb->mac_len = hlen;
if (len > ieee802154_max_payload(&hdr))
return -EMSGSIZE;
return hlen;
}
static const struct wpan_dev_header_ops ieee802154_header_ops = {
.create = ieee802154_header_create,
};
/* This header create functionality assumes a 8 byte array for
* source and destination pointer at maximum. To adapt this for
* the 802.15.4 dataframe header we use extended address handling
* here only and intra pan connection. fc fields are mostly fallback
* handling. For provide dev_hard_header for dgram sockets.
*/
static int mac802154_header_create(struct sk_buff *skb,
struct net_device *dev,
unsigned short type,
const void *daddr,
const void *saddr,
unsigned len)
{
struct ieee802154_hdr hdr;
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
struct ieee802154_mac_cb cb = { };
int hlen;
if (!daddr)
return -EINVAL;
memset(&hdr.fc, 0, sizeof(hdr.fc));
hdr.fc.type = IEEE802154_FC_TYPE_DATA;
hdr.fc.ack_request = wpan_dev->ackreq;
hdr.seq = atomic_inc_return(&dev->ieee802154_ptr->dsn) & 0xFF;
/* TODO currently a workaround to give zero cb block to set
* security parameters defaults according MIB.
*/
if (mac802154_set_header_security(sdata, &hdr, &cb) < 0)
return -EINVAL;
hdr.dest.pan_id = wpan_dev->pan_id;
hdr.dest.mode = IEEE802154_ADDR_LONG;
ieee802154_be64_to_le64(&hdr.dest.extended_addr, daddr);
hdr.source.pan_id = hdr.dest.pan_id;
hdr.source.mode = IEEE802154_ADDR_LONG;
if (!saddr)
hdr.source.extended_addr = wpan_dev->extended_addr;
else
ieee802154_be64_to_le64(&hdr.source.extended_addr, saddr);
hlen = ieee802154_hdr_push(skb, &hdr);
if (hlen < 0)
return -EINVAL;
skb_reset_mac_header(skb);
skb->mac_len = hlen;
if (len > ieee802154_max_payload(&hdr))
return -EMSGSIZE;
return hlen;
}
static int
mac802154_header_parse(const struct sk_buff *skb, unsigned char *haddr)
{
struct ieee802154_hdr hdr;
if (ieee802154_hdr_peek_addrs(skb, &hdr) < 0) {
pr_debug("malformed packet\n");
return 0;
}
if (hdr.source.mode == IEEE802154_ADDR_LONG) {
ieee802154_le64_to_be64(haddr, &hdr.source.extended_addr);
return IEEE802154_EXTENDED_ADDR_LEN;
}
return 0;
}
static const struct header_ops mac802154_header_ops = {
.create = mac802154_header_create,
.parse = mac802154_header_parse,
};
static const struct net_device_ops mac802154_wpan_ops = {
.ndo_open = mac802154_wpan_open,
.ndo_stop = mac802154_slave_close,
.ndo_start_xmit = ieee802154_subif_start_xmit,
.ndo_do_ioctl = mac802154_wpan_ioctl,
.ndo_set_mac_address = mac802154_wpan_mac_addr,
};
static const struct net_device_ops mac802154_monitor_ops = {
.ndo_open = mac802154_wpan_open,
.ndo_stop = mac802154_slave_close,
.ndo_start_xmit = ieee802154_monitor_start_xmit,
};
static void mac802154_wpan_free(struct net_device *dev)
{
struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
mac802154_llsec_destroy(&sdata->sec);
}
static void ieee802154_if_setup(struct net_device *dev)
{
dev->addr_len = IEEE802154_EXTENDED_ADDR_LEN;
memset(dev->broadcast, 0xff, IEEE802154_EXTENDED_ADDR_LEN);
/* Let hard_header_len set to IEEE802154_MIN_HEADER_LEN. AF_PACKET
* will not send frames without any payload, but ack frames
* has no payload, so substract one that we can send a 3 bytes
* frame. The xmit callback assumes at least a hard header where two
* bytes fc and sequence field are set.
*/
dev->hard_header_len = IEEE802154_MIN_HEADER_LEN - 1;
/* The auth_tag header is for security and places in private payload
* room of mac frame which stucks between payload and FCS field.
*/
dev->needed_tailroom = IEEE802154_MAX_AUTH_TAG_LEN +
IEEE802154_FCS_LEN;
/* The mtu size is the payload without mac header in this case.
* We have a dynamic length header with a minimum header length
* which is hard_header_len. In this case we let mtu to the size
* of maximum payload which is IEEE802154_MTU - IEEE802154_FCS_LEN -
* hard_header_len. The FCS which is set by hardware or ndo_start_xmit
* and the minimum mac header which can be evaluated inside driver
* layer. The rest of mac header will be part of payload if greater
* than hard_header_len.
*/
dev->mtu = IEEE802154_MTU - IEEE802154_FCS_LEN -
dev->hard_header_len;
dev->tx_queue_len = 300;
dev->flags = IFF_NOARP | IFF_BROADCAST;
}
static int
ieee802154_setup_sdata(struct ieee802154_sub_if_data *sdata,
enum nl802154_iftype type)
{
struct wpan_dev *wpan_dev = &sdata->wpan_dev;
int ret;
u8 tmp;
/* set some type-dependent values */
sdata->wpan_dev.iftype = type;
get_random_bytes(&tmp, sizeof(tmp));
atomic_set(&wpan_dev->bsn, tmp);
get_random_bytes(&tmp, sizeof(tmp));
atomic_set(&wpan_dev->dsn, tmp);
/* defaults per 802.15.4-2011 */
wpan_dev->min_be = 3;
wpan_dev->max_be = 5;
wpan_dev->csma_retries = 4;
wpan_dev->frame_retries = 3;
wpan_dev->pan_id = cpu_to_le16(IEEE802154_PANID_BROADCAST);
wpan_dev->short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
switch (type) {
case NL802154_IFTYPE_NODE:
ieee802154_be64_to_le64(&wpan_dev->extended_addr,
sdata->dev->dev_addr);
sdata->dev->header_ops = &mac802154_header_ops;
sdata->dev->needs_free_netdev = true;
sdata->dev->priv_destructor = mac802154_wpan_free;
sdata->dev->netdev_ops = &mac802154_wpan_ops;
sdata->dev->ml_priv = &mac802154_mlme_wpan;
wpan_dev->promiscuous_mode = false;
wpan_dev->header_ops = &ieee802154_header_ops;
mutex_init(&sdata->sec_mtx);
mac802154_llsec_init(&sdata->sec);
ret = mac802154_wpan_update_llsec(sdata->dev);
if (ret < 0)
return ret;
break;
case NL802154_IFTYPE_MONITOR:
sdata->dev->needs_free_netdev = true;
sdata->dev->netdev_ops = &mac802154_monitor_ops;
wpan_dev->promiscuous_mode = true;
break;
default:
BUG();
}
return 0;
}
struct net_device *
ieee802154_if_add(struct ieee802154_local *local, const char *name,
unsigned char name_assign_type, enum nl802154_iftype type,
__le64 extended_addr)
{
struct net_device *ndev = NULL;
struct ieee802154_sub_if_data *sdata = NULL;
int ret;
ASSERT_RTNL();
ndev = alloc_netdev(sizeof(*sdata), name,
name_assign_type, ieee802154_if_setup);
if (!ndev)
return ERR_PTR(-ENOMEM);
ndev->needed_headroom = local->hw.extra_tx_headroom +
IEEE802154_MAX_HEADER_LEN;
ret = dev_alloc_name(ndev, ndev->name);
if (ret < 0)
goto err;
ieee802154_le64_to_be64(ndev->perm_addr,
&local->hw.phy->perm_extended_addr);
switch (type) {
case NL802154_IFTYPE_NODE:
ndev->type = ARPHRD_IEEE802154;
if (ieee802154_is_valid_extended_unicast_addr(extended_addr))
ieee802154_le64_to_be64(ndev->dev_addr, &extended_addr);
else
memcpy(ndev->dev_addr, ndev->perm_addr,
IEEE802154_EXTENDED_ADDR_LEN);
break;
case NL802154_IFTYPE_MONITOR:
ndev->type = ARPHRD_IEEE802154_MONITOR;
break;
default:
ret = -EINVAL;
goto err;
}
/* TODO check this */
SET_NETDEV_DEV(ndev, &local->phy->dev);
dev_net_set(ndev, wpan_phy_net(local->hw.phy));
sdata = netdev_priv(ndev);
ndev->ieee802154_ptr = &sdata->wpan_dev;
memcpy(sdata->name, ndev->name, IFNAMSIZ);
sdata->dev = ndev;
sdata->wpan_dev.wpan_phy = local->hw.phy;
sdata->local = local;
/* setup type-dependent data */
ret = ieee802154_setup_sdata(sdata, type);
if (ret)
goto err;
ret = register_netdevice(ndev);
if (ret < 0)
goto err;
mutex_lock(&local->iflist_mtx);
list_add_tail_rcu(&sdata->list, &local->interfaces);
mutex_unlock(&local->iflist_mtx);
return ndev;
err:
free_netdev(ndev);
return ERR_PTR(ret);
}
void ieee802154_if_remove(struct ieee802154_sub_if_data *sdata)
{
ASSERT_RTNL();
mutex_lock(&sdata->local->iflist_mtx);
list_del_rcu(&sdata->list);
mutex_unlock(&sdata->local->iflist_mtx);
synchronize_rcu();
unregister_netdevice(sdata->dev);
}
void ieee802154_remove_interfaces(struct ieee802154_local *local)
{
struct ieee802154_sub_if_data *sdata, *tmp;
mutex_lock(&local->iflist_mtx);
list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
list_del(&sdata->list);
unregister_netdevice(sdata->dev);
}
mutex_unlock(&local->iflist_mtx);
}
static int netdev_notify(struct notifier_block *nb,
unsigned long state, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct ieee802154_sub_if_data *sdata;
if (state != NETDEV_CHANGENAME)
return NOTIFY_DONE;
if (!dev->ieee802154_ptr || !dev->ieee802154_ptr->wpan_phy)
return NOTIFY_DONE;
if (dev->ieee802154_ptr->wpan_phy->privid != mac802154_wpan_phy_privid)
return NOTIFY_DONE;
sdata = IEEE802154_DEV_TO_SUB_IF(dev);
memcpy(sdata->name, dev->name, IFNAMSIZ);
return NOTIFY_OK;
}
static struct notifier_block mac802154_netdev_notifier = {
.notifier_call = netdev_notify,
};
int ieee802154_iface_init(void)
{
return register_netdevice_notifier(&mac802154_netdev_notifier);
}
void ieee802154_iface_exit(void)
{
unregister_netdevice_notifier(&mac802154_netdev_notifier);
}