From f7ca38dfe58c20cb1aa2ed9643187e8b194b5bae Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 25 Nov 2010 10:02:29 +0100 Subject: [PATCH] nl80211/cfg80211: extend mgmt-tx API for off-channel With p2p, it is sometimes necessary to transmit a frame (typically an action frame) on another channel than the current channel. Enable this through the CMD_FRAME API, and allow it to wait for a response. A new command allows that wait to be aborted. However, allow userspace to specify whether or not it wants to allow off-channel TX, it may actually want to use the same channel only. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- include/linux/nl80211.h | 25 +++++++++++++++++----- include/net/cfg80211.h | 11 +++++++--- net/mac80211/cfg.c | 7 ++++-- net/wireless/core.h | 4 ++-- net/wireless/mlme.c | 9 ++++---- net/wireless/nl80211.c | 57 +++++++++++++++++++++++++++++++++++++++++++------ 6 files changed, 91 insertions(+), 22 deletions(-) diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h index d706bf3..5cfa579 100644 --- a/include/linux/nl80211.h +++ b/include/linux/nl80211.h @@ -358,11 +358,16 @@ * user space application). %NL80211_ATTR_FRAME is used to specify the * frame contents (including header). %NL80211_ATTR_WIPHY_FREQ (and * optionally %NL80211_ATTR_WIPHY_CHANNEL_TYPE) is used to indicate on - * which channel the frame is to be transmitted or was received. This - * channel has to be the current channel (remain-on-channel or the - * operational channel). When called, this operation returns a cookie - * (%NL80211_ATTR_COOKIE) that will be included with the TX status event - * pertaining to the TX request. + * which channel the frame is to be transmitted or was received. If this + * channel is not the current channel (remain-on-channel or the + * operational channel) the device will switch to the given channel and + * transmit the frame, optionally waiting for a response for the time + * specified using %NL80211_ATTR_DURATION. When called, this operation + * returns a cookie (%NL80211_ATTR_COOKIE) that will be included with the + * TX status event pertaining to the TX request. + * @NL80211_CMD_FRAME_WAIT_CANCEL: When an off-channel TX was requested, this + * command may be used with the corresponding cookie to cancel the wait + * time if it is known that it is no longer necessary. * @NL80211_CMD_ACTION: Alias for @NL80211_CMD_FRAME for backward compatibility. * @NL80211_CMD_FRAME_TX_STATUS: Report TX status of a management frame * transmitted with %NL80211_CMD_FRAME. %NL80211_ATTR_COOKIE identifies @@ -493,6 +498,8 @@ enum nl80211_commands { NL80211_CMD_SET_CHANNEL, NL80211_CMD_SET_WDS_PEER, + NL80211_CMD_FRAME_WAIT_CANCEL, + /* add new commands above here */ /* used to define NL80211_CMD_MAX below */ @@ -828,6 +835,12 @@ enum nl80211_commands { * * @NL80211_ATTR_MCAST_RATE: Multicast tx rate (in 100 kbps) for IBSS * + * @NL80211_ATTR_OFFCHANNEL_TX_OK: For management frame TX, the frame may be + * transmitted on another channel when the channel given doesn't match + * the current channel. If the current channel doesn't match and this + * flag isn't set, the frame will be rejected. This is also used as an + * nl80211 capability flag. + * * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use */ @@ -1002,6 +1015,8 @@ enum nl80211_attrs { NL80211_ATTR_MCAST_RATE, + NL80211_ATTR_OFFCHANNEL_TX_OK, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 0663945..49a7c53 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1134,7 +1134,9 @@ struct cfg80211_pmksa { * @cancel_remain_on_channel: Cancel an on-going remain-on-channel operation. * This allows the operation to be terminated prior to timeout based on * the duration value. - * @mgmt_tx: Transmit a management frame + * @mgmt_tx: Transmit a management frame. + * @mgmt_tx_cancel_wait: Cancel the wait time from transmitting a management + * frame on another channel * * @testmode_cmd: run a test mode command * @@ -1291,10 +1293,13 @@ struct cfg80211_ops { u64 cookie); int (*mgmt_tx)(struct wiphy *wiphy, struct net_device *dev, - struct ieee80211_channel *chan, + struct ieee80211_channel *chan, bool offchan, enum nl80211_channel_type channel_type, - bool channel_type_valid, + bool channel_type_valid, unsigned int wait, const u8 *buf, size_t len, u64 *cookie); + int (*mgmt_tx_cancel_wait)(struct wiphy *wiphy, + struct net_device *dev, + u64 cookie); int (*set_power_mgmt)(struct wiphy *wiphy, struct net_device *dev, bool enabled, int timeout); diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 0c54407..aac2d7d 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1552,9 +1552,9 @@ static int ieee80211_cancel_remain_on_channel(struct wiphy *wiphy, } static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct net_device *dev, - struct ieee80211_channel *chan, + struct ieee80211_channel *chan, bool offchan, enum nl80211_channel_type channel_type, - bool channel_type_valid, + bool channel_type_valid, unsigned int wait, const u8 *buf, size_t len, u64 *cookie) { struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); @@ -1565,6 +1565,9 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct net_device *dev, u32 flags = IEEE80211_TX_INTFL_NL80211_FRAME_TX | IEEE80211_TX_CTL_REQ_TX_STATUS; + if (offchan) + return -EOPNOTSUPP; + /* Check that we are on the requested channel for transmission */ if (chan != local->tmp_channel && chan != local->oper_channel) diff --git a/net/wireless/core.h b/net/wireless/core.h index 6583cca..ee80ad8 100644 --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -341,9 +341,9 @@ void cfg80211_mlme_unregister_socket(struct wireless_dev *wdev, u32 nlpid); void cfg80211_mlme_purge_registrations(struct wireless_dev *wdev); int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev, struct net_device *dev, - struct ieee80211_channel *chan, + struct ieee80211_channel *chan, bool offchan, enum nl80211_channel_type channel_type, - bool channel_type_valid, + bool channel_type_valid, unsigned int wait, const u8 *buf, size_t len, u64 *cookie); /* SME */ diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c index 6980a0c..d7680f2 100644 --- a/net/wireless/mlme.c +++ b/net/wireless/mlme.c @@ -864,9 +864,9 @@ void cfg80211_mlme_purge_registrations(struct wireless_dev *wdev) int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev, struct net_device *dev, - struct ieee80211_channel *chan, + struct ieee80211_channel *chan, bool offchan, enum nl80211_channel_type channel_type, - bool channel_type_valid, + bool channel_type_valid, unsigned int wait, const u8 *buf, size_t len, u64 *cookie) { struct wireless_dev *wdev = dev->ieee80211_ptr; @@ -946,8 +946,9 @@ int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev, return -EINVAL; /* Transmit the Action frame as requested by user space */ - return rdev->ops->mgmt_tx(&rdev->wiphy, dev, chan, channel_type, - channel_type_valid, buf, len, cookie); + return rdev->ops->mgmt_tx(&rdev->wiphy, dev, chan, offchan, + channel_type, channel_type_valid, + wait, buf, len, cookie); } bool cfg80211_rx_mgmt(struct net_device *dev, int freq, const u8 *buf, diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 67ff7e9..960be4e 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -163,16 +163,13 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = { [NL80211_ATTR_CQM] = { .type = NLA_NESTED, }, [NL80211_ATTR_LOCAL_STATE_CHANGE] = { .type = NLA_FLAG }, [NL80211_ATTR_AP_ISOLATE] = { .type = NLA_U8 }, - [NL80211_ATTR_WIPHY_TX_POWER_SETTING] = { .type = NLA_U32 }, [NL80211_ATTR_WIPHY_TX_POWER_LEVEL] = { .type = NLA_U32 }, - [NL80211_ATTR_FRAME_TYPE] = { .type = NLA_U16 }, - [NL80211_ATTR_WIPHY_ANTENNA_TX] = { .type = NLA_U32 }, [NL80211_ATTR_WIPHY_ANTENNA_RX] = { .type = NLA_U32 }, - [NL80211_ATTR_MCAST_RATE] = { .type = NLA_U32 }, + [NL80211_ATTR_OFFCHANNEL_TX_OK] = { .type = NLA_FLAG }, }; /* policy for the key attributes */ @@ -677,6 +674,7 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags, CMD(remain_on_channel, REMAIN_ON_CHANNEL); CMD(set_bitrate_mask, SET_TX_BITRATE_MASK); CMD(mgmt_tx, FRAME); + CMD(mgmt_tx_cancel_wait, FRAME_WAIT_CANCEL); if (dev->wiphy.flags & WIPHY_FLAG_NETNS_OK) { i++; NLA_PUT_U32(msg, i, NL80211_CMD_SET_WIPHY_NETNS); @@ -698,6 +696,10 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags, nla_nest_end(msg, nl_cmds); + /* for now at least assume all drivers have it */ + if (dev->ops->mgmt_tx) + NLA_PUT_FLAG(msg, NL80211_ATTR_OFFCHANNEL_TX_OK); + if (mgmt_stypes) { u16 stypes; struct nlattr *nl_ftypes, *nl_ifs; @@ -4244,6 +4246,8 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info) void *hdr; u64 cookie; struct sk_buff *msg; + unsigned int wait = 0; + bool offchan; if (!info->attrs[NL80211_ATTR_FRAME] || !info->attrs[NL80211_ATTR_WIPHY_FREQ]) @@ -4260,6 +4264,12 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info) dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO) return -EOPNOTSUPP; + if (info->attrs[NL80211_ATTR_DURATION]) { + if (!rdev->ops->mgmt_tx_cancel_wait) + return -EINVAL; + wait = nla_get_u32(info->attrs[NL80211_ATTR_DURATION]); + } + if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]) { channel_type = nla_get_u32( info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]); @@ -4271,6 +4281,8 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info) channel_type_valid = true; } + offchan = info->attrs[NL80211_ATTR_OFFCHANNEL_TX_OK]; + freq = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]); chan = rdev_freq_to_chan(rdev, freq, channel_type); if (chan == NULL) @@ -4287,8 +4299,8 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info) err = PTR_ERR(hdr); goto free_msg; } - err = cfg80211_mlme_mgmt_tx(rdev, dev, chan, channel_type, - channel_type_valid, + err = cfg80211_mlme_mgmt_tx(rdev, dev, chan, offchan, channel_type, + channel_type_valid, wait, nla_data(info->attrs[NL80211_ATTR_FRAME]), nla_len(info->attrs[NL80211_ATTR_FRAME]), &cookie); @@ -4307,6 +4319,31 @@ static int nl80211_tx_mgmt(struct sk_buff *skb, struct genl_info *info) return err; } +static int nl80211_tx_mgmt_cancel_wait(struct sk_buff *skb, struct genl_info *info) +{ + struct cfg80211_registered_device *rdev = info->user_ptr[0]; + struct net_device *dev = info->user_ptr[1]; + u64 cookie; + + if (!info->attrs[NL80211_ATTR_COOKIE]) + return -EINVAL; + + if (!rdev->ops->mgmt_tx_cancel_wait) + return -EOPNOTSUPP; + + if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_STATION && + dev->ieee80211_ptr->iftype != NL80211_IFTYPE_ADHOC && + dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_CLIENT && + dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP && + dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP_VLAN && + dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO) + return -EOPNOTSUPP; + + cookie = nla_get_u64(info->attrs[NL80211_ATTR_COOKIE]); + + return rdev->ops->mgmt_tx_cancel_wait(&rdev->wiphy, dev, cookie); +} + static int nl80211_set_power_save(struct sk_buff *skb, struct genl_info *info) { struct cfg80211_registered_device *rdev = info->user_ptr[0]; @@ -4880,6 +4917,14 @@ static struct genl_ops nl80211_ops[] = { NL80211_FLAG_NEED_RTNL, }, { + .cmd = NL80211_CMD_FRAME_WAIT_CANCEL, + .doit = nl80211_tx_mgmt_cancel_wait, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + .internal_flags = NL80211_FLAG_NEED_NETDEV_UP | + NL80211_FLAG_NEED_RTNL, + }, + { .cmd = NL80211_CMD_SET_POWER_SAVE, .doit = nl80211_set_power_save, .policy = nl80211_policy, -- 2.7.4