nl80211: vendor command support

Add support for vendor-specific commands to nl80211. This is
intended to be used for really vendor-specific functionality
that can't be implemented in a generic fashion for any reason.
It's *NOT* intended to be used for any normal/generic feature
or any optimisations that could be implemented across drivers.

Currently, only vendor commands (with replies) are supported,
no dump operations or vendor-specific notifications.

Also add a function wdev_to_ieee80211_vif() to mac80211 which
is needed for mac80211-based drivers wanting to implement any
vendor commands.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2013-11-13 13:37:47 +01:00
parent 7869303b17
commit ad7e718c9b
6 changed files with 348 additions and 74 deletions

View File

@ -2679,6 +2679,34 @@ struct wiphy_coalesce_support {
int max_pkt_offset;
};
/**
* enum wiphy_vendor_command_flags - validation flags for vendor commands
* @WIPHY_VENDOR_CMD_NEED_WDEV: vendor command requires wdev
* @WIPHY_VENDOR_CMD_NEED_NETDEV: vendor command requires netdev
* @WIPHY_VENDOR_CMD_NEED_RUNNING: interface/wdev must be up & running
* (must be combined with %_WDEV or %_NETDEV)
*/
enum wiphy_vendor_command_flags {
WIPHY_VENDOR_CMD_NEED_WDEV = BIT(0),
WIPHY_VENDOR_CMD_NEED_NETDEV = BIT(1),
WIPHY_VENDOR_CMD_NEED_RUNNING = BIT(2),
};
/**
* struct wiphy_vendor_command - vendor command definition
* @info: vendor command identifying information, as used in nl80211
* @flags: flags, see &enum wiphy_vendor_command_flags
* @doit: callback for the operation, note that wdev is %NULL if the
* flags didn't ask for a wdev and non-%NULL otherwise; the data
* pointer may be %NULL if userspace provided no data at all
*/
struct wiphy_vendor_command {
struct nl80211_vendor_cmd_info info;
u32 flags;
int (*doit)(struct wiphy *wiphy, struct wireless_dev *wdev,
const void *data, int data_len);
};
/**
* struct wiphy - wireless hardware description
* @reg_notifier: the driver's regulatory notification callback,
@ -2792,6 +2820,9 @@ struct wiphy_coalesce_support {
* @extended_capabilities_mask: mask of the valid values
* @extended_capabilities_len: length of the extended capabilities
* @coalesce: packet coalescing support information
*
* @vendor_commands: array of vendor commands supported by the hardware
* @n_vendor_commands: number of vendor commands
*/
struct wiphy {
/* assign these fields before you register the wiphy */
@ -2903,6 +2934,9 @@ struct wiphy {
const struct wiphy_coalesce_support *coalesce;
const struct wiphy_vendor_command *vendor_commands;
int n_vendor_commands;
char priv[0] __aligned(NETDEV_ALIGN);
};
@ -3847,6 +3881,75 @@ void wiphy_rfkill_start_polling(struct wiphy *wiphy);
*/
void wiphy_rfkill_stop_polling(struct wiphy *wiphy);
/**
* DOC: Vendor commands
*
* Occasionally, there are special protocol or firmware features that
* can't be implemented very openly. For this and similar cases, the
* vendor command functionality allows implementing the features with
* (typically closed-source) userspace and firmware, using nl80211 as
* the configuration mechanism.
*
* A driver supporting vendor commands must register them as an array
* in struct wiphy, with handlers for each one, each command has an
* OUI and sub command ID to identify it.
*
* Note that this feature should not be (ab)used to implement protocol
* features that could openly be shared across drivers. In particular,
* it must never be required to use vendor commands to implement any
* "normal" functionality that higher-level userspace like connection
* managers etc. need.
*/
struct sk_buff *__cfg80211_alloc_reply_skb(struct wiphy *wiphy,
enum nl80211_commands cmd,
enum nl80211_attrs attr,
int approxlen);
/**
* cfg80211_vendor_cmd_alloc_reply_skb - allocate vendor command reply
* @wiphy: the wiphy
* @approxlen: an upper bound of the length of the data that will
* be put into the skb
*
* This function allocates and pre-fills an skb for a reply to
* a vendor command. Since it is intended for a reply, calling
* it outside of a vendor command's doit() operation is invalid.
*
* The returned skb is pre-filled with some identifying data in
* a way that any data that is put into the skb (with skb_put(),
* nla_put() or similar) will end up being within the
* %NL80211_ATTR_VENDOR_DATA attribute, so all that needs to be done
* with the skb is adding data for the corresponding userspace tool
* which can then read that data out of the vendor data attribute.
* You must not modify the skb in any other way.
*
* When done, call cfg80211_vendor_cmd_reply() with the skb and return
* its error code as the result of the doit() operation.
*
* Return: An allocated and pre-filled skb. %NULL if any errors happen.
*/
static inline struct sk_buff *
cfg80211_vendor_cmd_alloc_reply_skb(struct wiphy *wiphy, int approxlen)
{
return __cfg80211_alloc_reply_skb(wiphy, NL80211_CMD_VENDOR,
NL80211_ATTR_VENDOR_DATA, approxlen);
}
/**
* cfg80211_vendor_cmd_reply - send the reply skb
* @skb: The skb, must have been allocated with
* cfg80211_vendor_cmd_alloc_reply_skb()
*
* Since calling this function will usually be the last thing
* before returning from the vendor command doit() you should
* return the error code. Note that this function consumes the
* skb regardless of the return value.
*
* Return: An error code or 0 on success.
*/
int cfg80211_vendor_cmd_reply(struct sk_buff *skb);
#ifdef CONFIG_NL80211_TESTMODE
/**
* DOC: Test mode
@ -3882,8 +3985,12 @@ void wiphy_rfkill_stop_polling(struct wiphy *wiphy);
*
* Return: An allocated and pre-filled skb. %NULL if any errors happen.
*/
struct sk_buff *cfg80211_testmode_alloc_reply_skb(struct wiphy *wiphy,
int approxlen);
static inline struct sk_buff *
cfg80211_testmode_alloc_reply_skb(struct wiphy *wiphy, int approxlen)
{
return __cfg80211_alloc_reply_skb(wiphy, NL80211_CMD_TESTMODE,
NL80211_ATTR_TESTDATA, approxlen);
}
/**
* cfg80211_testmode_reply - send the reply skb
@ -3897,7 +4004,10 @@ struct sk_buff *cfg80211_testmode_alloc_reply_skb(struct wiphy *wiphy,
*
* Return: An error code or 0 on success.
*/
int cfg80211_testmode_reply(struct sk_buff *skb);
static inline int cfg80211_testmode_reply(struct sk_buff *skb)
{
return cfg80211_vendor_cmd_reply(skb);
}
/**
* cfg80211_testmode_alloc_event_skb - allocate testmode event

View File

@ -1162,6 +1162,19 @@ static inline bool ieee80211_vif_is_mesh(struct ieee80211_vif *vif)
return false;
}
/**
* wdev_to_ieee80211_vif - return a vif struct from a wdev
* @wdev: the wdev to get the vif for
*
* This can be used by mac80211 drivers with direct cfg80211 APIs
* (like the vendor commands) that get a wdev.
*
* Note that this function may return %NULL if the given wdev isn't
* associated with a vif that the driver knows about (e.g. monitor
* or AP_VLAN interfaces.)
*/
struct ieee80211_vif *wdev_to_ieee80211_vif(struct wireless_dev *wdev);
/**
* enum ieee80211_key_flags - key flags
*

View File

@ -693,6 +693,15 @@
* other station that transmission must be blocked until the channel
* switch is complete.
*
* @NL80211_CMD_VENDOR: Vendor-specified command/event. The command is specified
* by the %NL80211_ATTR_VENDOR_ID attribute and a sub-command in
* %NL80211_ATTR_VENDOR_SUBCMD. Parameter(s) can be transported in
* %NL80211_ATTR_VENDOR_DATA.
* For feature advertisement, the %NL80211_ATTR_VENDOR_DATA attribute is
* used in the wiphy data as a nested attribute containing descriptions
* (&struct nl80211_vendor_cmd_info) of the supported vendor commands.
* This may also be sent as an event with the same attributes.
*
* @NL80211_CMD_MAX: highest used command number
* @__NL80211_CMD_AFTER_LAST: internal use
*/
@ -860,6 +869,8 @@ enum nl80211_commands {
NL80211_CMD_CHANNEL_SWITCH,
NL80211_CMD_VENDOR,
/* add new commands above here */
/* used to define NL80211_CMD_MAX below */
@ -1524,6 +1535,12 @@ enum nl80211_commands {
* Notification Element based on association request when used with
* %NL80211_CMD_NEW_STATION; u8 attribute.
*
* @NL80211_ATTR_VENDOR_ID: The vendor ID, either a 24-bit OUI or, if
* %NL80211_VENDOR_ID_IS_LINUX is set, a special Linux ID (not used yet)
* @NL80211_ATTR_VENDOR_SUBCMD: vendor sub-command
* @NL80211_ATTR_VENDOR_DATA: data for the vendor command, if any; this
* attribute is also used for vendor command feature advertisement
*
* @NL80211_ATTR_MAX: highest attribute number currently defined
* @__NL80211_ATTR_AFTER_LAST: internal use
*/
@ -1845,6 +1862,10 @@ enum nl80211_attrs {
NL80211_ATTR_OPMODE_NOTIF,
NL80211_ATTR_VENDOR_ID,
NL80211_ATTR_VENDOR_SUBCMD,
NL80211_ATTR_VENDOR_DATA,
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
@ -3965,4 +3986,24 @@ enum nl80211_rxmgmt_flags {
NL80211_RXMGMT_FLAG_ANSWERED = 1 << 0,
};
/*
* If this flag is unset, the lower 24 bits are an OUI, if set
* a Linux nl80211 vendor ID is used (no such IDs are allocated
* yet, so that's not valid so far)
*/
#define NL80211_VENDOR_ID_IS_LINUX 0x80000000
/**
* struct nl80211_vendor_cmd_info - vendor command data
* @vendor_id: If the %NL80211_VENDOR_ID_IS_LINUX flag is clear, then the
* value is a 24-bit OUI; if it is set then a separately allocated ID
* may be used, but no such IDs are allocated yet. New IDs should be
* added to this file when needed.
* @subcmd: sub-command ID for the command
*/
struct nl80211_vendor_cmd_info {
__u32 vendor_id;
__u32 subcmd;
};
#endif /* __LINUX_NL80211_H */

View File

@ -642,6 +642,17 @@ void ieee80211_iterate_active_interfaces_rtnl(
}
EXPORT_SYMBOL_GPL(ieee80211_iterate_active_interfaces_rtnl);
struct ieee80211_vif *wdev_to_ieee80211_vif(struct wireless_dev *wdev)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
if (!ieee80211_sdata_running(sdata) ||
!(sdata->flags & IEEE80211_SDATA_IN_DRIVER))
return NULL;
return &sdata->vif;
}
EXPORT_SYMBOL_GPL(wdev_to_ieee80211_vif);
/*
* Nothing should have been stuffed into the workqueue during
* the suspend->resume cycle. If this WARN is seen then there

View File

@ -67,9 +67,7 @@ struct cfg80211_registered_device {
struct work_struct scan_done_wk;
struct work_struct sched_scan_results_wk;
#ifdef CONFIG_NL80211_TESTMODE
struct genl_info *testmode_info;
#endif
struct genl_info *cur_cmd_info;
struct work_struct conn_work;
struct work_struct event_work;

View File

@ -358,6 +358,9 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
[NL80211_ATTR_STA_SUPPORTED_OPER_CLASSES] = { .type = NLA_BINARY },
[NL80211_ATTR_HANDLE_DFS] = { .type = NLA_FLAG },
[NL80211_ATTR_OPMODE_NOTIF] = { .type = NLA_U8 },
[NL80211_ATTR_VENDOR_ID] = { .type = NLA_U32 },
[NL80211_ATTR_VENDOR_SUBCMD] = { .type = NLA_U32 },
[NL80211_ATTR_VENDOR_DATA] = { .type = NLA_BINARY },
};
/* policy for the key attributes */
@ -1166,6 +1169,7 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *dev,
struct nlattr *nl_bands, *nl_band;
struct nlattr *nl_freqs, *nl_freq;
struct nlattr *nl_cmds;
struct nlattr *nl_vendor_cmds;
enum ieee80211_band band;
struct ieee80211_channel *chan;
int i;
@ -1561,6 +1565,19 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *dev,
(nla_put_flag(msg, NL80211_ATTR_SUPPORT_5_MHZ) ||
nla_put_flag(msg, NL80211_ATTR_SUPPORT_10_MHZ)))
goto nla_put_failure;
state->split_start++;
break;
case 11:
nl_vendor_cmds = nla_nest_start(msg, NL80211_ATTR_VENDOR_DATA);
if (!nl_vendor_cmds)
goto nla_put_failure;
for (i = 0; i < dev->wiphy.n_vendor_commands; i++)
if (nla_put(msg, i + 1,
sizeof(struct nl80211_vendor_cmd_info),
&dev->wiphy.vendor_commands[i].info))
goto nla_put_failure;
nla_nest_end(msg, nl_vendor_cmds);
/* done */
state->split_start = 0;
@ -6682,6 +6699,40 @@ static int nl80211_set_mcast_rate(struct sk_buff *skb, struct genl_info *info)
return err;
}
static struct sk_buff *
__cfg80211_alloc_vendor_skb(struct cfg80211_registered_device *rdev,
int approxlen, u32 portid, u32 seq,
enum nl80211_commands cmd,
enum nl80211_attrs attr, gfp_t gfp)
{
struct sk_buff *skb;
void *hdr;
struct nlattr *data;
skb = nlmsg_new(approxlen + 100, gfp);
if (!skb)
return NULL;
hdr = nl80211hdr_put(skb, portid, seq, 0, cmd);
if (!hdr) {
kfree_skb(skb);
return NULL;
}
if (nla_put_u32(skb, NL80211_ATTR_WIPHY, rdev->wiphy_idx))
goto nla_put_failure;
data = nla_nest_start(skb, attr);
((void **)skb->cb)[0] = rdev;
((void **)skb->cb)[1] = hdr;
((void **)skb->cb)[2] = data;
return skb;
nla_put_failure:
kfree_skb(skb);
return NULL;
}
#ifdef CONFIG_NL80211_TESTMODE
static struct genl_multicast_group nl80211_testmode_mcgrp = {
@ -6710,11 +6761,11 @@ static int nl80211_testmode_do(struct sk_buff *skb, struct genl_info *info)
if (!info->attrs[NL80211_ATTR_TESTDATA])
return -EINVAL;
rdev->testmode_info = info;
rdev->cur_cmd_info = info;
err = rdev_testmode_cmd(rdev, wdev,
nla_data(info->attrs[NL80211_ATTR_TESTDATA]),
nla_len(info->attrs[NL80211_ATTR_TESTDATA]));
rdev->testmode_info = NULL;
rdev->cur_cmd_info = NULL;
return err;
}
@ -6814,77 +6865,14 @@ static int nl80211_testmode_dump(struct sk_buff *skb,
return err;
}
static struct sk_buff *
__cfg80211_testmode_alloc_skb(struct cfg80211_registered_device *rdev,
int approxlen, u32 portid, u32 seq, gfp_t gfp)
{
struct sk_buff *skb;
void *hdr;
struct nlattr *data;
skb = nlmsg_new(approxlen + 100, gfp);
if (!skb)
return NULL;
hdr = nl80211hdr_put(skb, portid, seq, 0, NL80211_CMD_TESTMODE);
if (!hdr) {
kfree_skb(skb);
return NULL;
}
if (nla_put_u32(skb, NL80211_ATTR_WIPHY, rdev->wiphy_idx))
goto nla_put_failure;
data = nla_nest_start(skb, NL80211_ATTR_TESTDATA);
((void **)skb->cb)[0] = rdev;
((void **)skb->cb)[1] = hdr;
((void **)skb->cb)[2] = data;
return skb;
nla_put_failure:
kfree_skb(skb);
return NULL;
}
struct sk_buff *cfg80211_testmode_alloc_reply_skb(struct wiphy *wiphy,
int approxlen)
{
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
if (WARN_ON(!rdev->testmode_info))
return NULL;
return __cfg80211_testmode_alloc_skb(rdev, approxlen,
rdev->testmode_info->snd_portid,
rdev->testmode_info->snd_seq,
GFP_KERNEL);
}
EXPORT_SYMBOL(cfg80211_testmode_alloc_reply_skb);
int cfg80211_testmode_reply(struct sk_buff *skb)
{
struct cfg80211_registered_device *rdev = ((void **)skb->cb)[0];
void *hdr = ((void **)skb->cb)[1];
struct nlattr *data = ((void **)skb->cb)[2];
if (WARN_ON(!rdev->testmode_info)) {
kfree_skb(skb);
return -EINVAL;
}
nla_nest_end(skb, data);
genlmsg_end(skb, hdr);
return genlmsg_reply(skb, rdev->testmode_info);
}
EXPORT_SYMBOL(cfg80211_testmode_reply);
struct sk_buff *cfg80211_testmode_alloc_event_skb(struct wiphy *wiphy,
int approxlen, gfp_t gfp)
{
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
return __cfg80211_testmode_alloc_skb(rdev, approxlen, 0, 0, gfp);
return __cfg80211_alloc_vendor_skb(rdev, approxlen, 0, 0,
NL80211_CMD_TESTMODE,
NL80211_ATTR_TESTDATA, gfp);
}
EXPORT_SYMBOL(cfg80211_testmode_alloc_event_skb);
@ -8867,6 +8855,111 @@ static int nl80211_crit_protocol_stop(struct sk_buff *skb,
return 0;
}
static int nl80211_vendor_cmd(struct sk_buff *skb, struct genl_info *info)
{
struct cfg80211_registered_device *rdev = info->user_ptr[0];
struct wireless_dev *wdev =
__cfg80211_wdev_from_attrs(genl_info_net(info), info->attrs);
int i, err;
u32 vid, subcmd;
if (!rdev->wiphy.vendor_commands)
return -EOPNOTSUPP;
if (IS_ERR(wdev)) {
err = PTR_ERR(wdev);
if (err != -EINVAL)
return err;
wdev = NULL;
} else if (wdev->wiphy != &rdev->wiphy) {
return -EINVAL;
}
if (!info->attrs[NL80211_ATTR_VENDOR_ID] ||
!info->attrs[NL80211_ATTR_VENDOR_SUBCMD])
return -EINVAL;
vid = nla_get_u32(info->attrs[NL80211_ATTR_VENDOR_ID]);
subcmd = nla_get_u32(info->attrs[NL80211_ATTR_VENDOR_SUBCMD]);
for (i = 0; i < rdev->wiphy.n_vendor_commands; i++) {
const struct wiphy_vendor_command *vcmd;
void *data = NULL;
int len = 0;
vcmd = &rdev->wiphy.vendor_commands[i];
if (vcmd->info.vendor_id != vid || vcmd->info.subcmd != subcmd)
continue;
if (vcmd->flags & (WIPHY_VENDOR_CMD_NEED_WDEV |
WIPHY_VENDOR_CMD_NEED_NETDEV)) {
if (!wdev)
return -EINVAL;
if (vcmd->flags & WIPHY_VENDOR_CMD_NEED_NETDEV &&
!wdev->netdev)
return -EINVAL;
if (vcmd->flags & WIPHY_VENDOR_CMD_NEED_RUNNING) {
if (wdev->netdev &&
!netif_running(wdev->netdev))
return -ENETDOWN;
if (!wdev->netdev && !wdev->p2p_started)
return -ENETDOWN;
}
} else {
wdev = NULL;
}
if (info->attrs[NL80211_ATTR_VENDOR_DATA]) {
data = nla_data(info->attrs[NL80211_ATTR_VENDOR_DATA]);
len = nla_len(info->attrs[NL80211_ATTR_VENDOR_DATA]);
}
rdev->cur_cmd_info = info;
err = rdev->wiphy.vendor_commands[i].doit(&rdev->wiphy, wdev,
data, len);
rdev->cur_cmd_info = NULL;
return err;
}
return -EOPNOTSUPP;
}
struct sk_buff *__cfg80211_alloc_reply_skb(struct wiphy *wiphy,
enum nl80211_commands cmd,
enum nl80211_attrs attr,
int approxlen)
{
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
if (WARN_ON(!rdev->cur_cmd_info))
return NULL;
return __cfg80211_alloc_vendor_skb(rdev, approxlen,
rdev->cur_cmd_info->snd_portid,
rdev->cur_cmd_info->snd_seq,
cmd, attr, GFP_KERNEL);
}
EXPORT_SYMBOL(__cfg80211_alloc_reply_skb);
int cfg80211_vendor_cmd_reply(struct sk_buff *skb)
{
struct cfg80211_registered_device *rdev = ((void **)skb->cb)[0];
void *hdr = ((void **)skb->cb)[1];
struct nlattr *data = ((void **)skb->cb)[2];
if (WARN_ON(!rdev->cur_cmd_info)) {
kfree_skb(skb);
return -EINVAL;
}
nla_nest_end(skb, data);
genlmsg_end(skb, hdr);
return genlmsg_reply(skb, rdev->cur_cmd_info);
}
EXPORT_SYMBOL_GPL(cfg80211_vendor_cmd_reply);
#define NL80211_FLAG_NEED_WIPHY 0x01
#define NL80211_FLAG_NEED_NETDEV 0x02
#define NL80211_FLAG_NEED_RTNL 0x04
@ -9591,6 +9684,14 @@ static struct genl_ops nl80211_ops[] = {
.internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
NL80211_FLAG_NEED_RTNL,
},
{
.cmd = NL80211_CMD_VENDOR,
.doit = nl80211_vendor_cmd,
.policy = nl80211_policy,
.flags = GENL_ADMIN_PERM,
.internal_flags = NL80211_FLAG_NEED_WIPHY |
NL80211_FLAG_NEED_RTNL,
},
};
static struct genl_multicast_group nl80211_mlme_mcgrp = {