From 1057d35ede5dbf7ed7842357564fb42c9b54ba50 Mon Sep 17 00:00:00 2001 From: Arik Nemtsov Date: Wed, 19 Nov 2014 12:54:26 +0200 Subject: [PATCH] cfg80211: introduce TDLS channel switch commands Introduce commands to initiate and cancel TDLS channel-switching. Once TDLS channel-switching is started, the lower level driver is responsible for continually initiating channel-switch operations and returning to the base (AP) channel to listen for beacons from time to time. Upon cancellation of the channel-switch all communication between the relevant TDLS peers will continue on the base channel. Signed-off-by: Arik Nemtsov Signed-off-by: Johannes Berg --- include/net/cfg80211.h | 14 +++++ include/uapi/linux/nl80211.h | 19 ++++++ net/wireless/core.c | 4 ++ net/wireless/nl80211.c | 108 +++++++++++++++++++++++++++++++++++ net/wireless/rdev-ops.h | 24 ++++++++ net/wireless/trace.h | 42 ++++++++++++++ 6 files changed, 211 insertions(+) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 220d5f5f1aca..8d04dfef32bf 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -2367,6 +2367,12 @@ struct cfg80211_qos_map { * (invoked with the wireless_dev mutex held) * @leave_ocb: leave the current OCB network * (invoked with the wireless_dev mutex held) + * + * @tdls_channel_switch: Start channel-switching with a TDLS peer. The driver + * is responsible for continually initiating channel-switching operations + * and returning to the base channel for communication with the AP. + * @tdls_cancel_channel_switch: Stop channel-switching with a TDLS peer. Both + * peers must be on the base channel when the call completes. */ struct cfg80211_ops { int (*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow); @@ -2622,6 +2628,14 @@ struct cfg80211_ops { u16 admitted_time); int (*del_tx_ts)(struct wiphy *wiphy, struct net_device *dev, u8 tsid, const u8 *peer); + + int (*tdls_channel_switch)(struct wiphy *wiphy, + struct net_device *dev, + const u8 *addr, u8 oper_class, + struct cfg80211_chan_def *chandef); + void (*tdls_cancel_channel_switch)(struct wiphy *wiphy, + struct net_device *dev, + const u8 *addr); }; /* diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index ccdeef28d672..365db67ca71d 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -762,6 +762,18 @@ * @NL80211_CMD_LEAVE_OCB: Leave the OCB network -- no special arguments, the * network is determined by the network interface. * + * @NL80211_CMD_TDLS_CHANNEL_SWITCH: Start channel-switching with a TDLS peer, + * identified by the %NL80211_ATTR_MAC parameter. A target channel is + * provided via %NL80211_ATTR_WIPHY_FREQ and other attributes determining + * channel width/type. The target operating class is given via + * %NL80211_ATTR_OPER_CLASS. + * The driver is responsible for continually initiating channel-switching + * operations and returning to the base channel for communication with the + * AP. + * @NL80211_CMD_TDLS_CANCEL_CHANNEL_SWITCH: Stop channel-switching with a TDLS + * peer given by %NL80211_ATTR_MAC. Both peers must be on the base channel + * when this command completes. + * * @NL80211_CMD_MAX: highest used command number * @__NL80211_CMD_AFTER_LAST: internal use */ @@ -943,6 +955,9 @@ enum nl80211_commands { NL80211_CMD_CH_SWITCH_STARTED_NOTIFY, + NL80211_CMD_TDLS_CHANNEL_SWITCH, + NL80211_CMD_TDLS_CANCEL_CHANNEL_SWITCH, + /* add new commands above here */ /* used to define NL80211_CMD_MAX below */ @@ -1669,6 +1684,8 @@ enum nl80211_commands { * @NL80211_ATTR_SMPS_MODE: SMPS mode to use (ap mode). see * &enum nl80211_smps_mode. * + * @NL80211_ATTR_OPER_CLASS: operating class + * * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use */ @@ -2021,6 +2038,8 @@ enum nl80211_attrs { NL80211_ATTR_SMPS_MODE, + NL80211_ATTR_OPER_CLASS, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, diff --git a/net/wireless/core.c b/net/wireless/core.c index a4d27927aba2..4c2e501203d1 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -541,6 +541,10 @@ int wiphy_register(struct wiphy *wiphy) !wiphy->wowlan->tcp)) return -EINVAL; #endif + if (WARN_ON((wiphy->features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH) && + (!rdev->ops->tdls_channel_switch || + !rdev->ops->tdls_cancel_channel_switch))) + return -EINVAL; if (WARN_ON(wiphy->coalesce && (!wiphy->coalesce->n_rules || diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index d0a8361b3395..27666f5e5050 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -9658,6 +9658,98 @@ static int nl80211_del_tx_ts(struct sk_buff *skb, struct genl_info *info) return err; } +static int nl80211_tdls_channel_switch(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]; + struct wireless_dev *wdev = dev->ieee80211_ptr; + struct cfg80211_chan_def chandef = {}; + const u8 *addr; + u8 oper_class; + int err; + + if (!rdev->ops->tdls_channel_switch || + !(rdev->wiphy.features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH)) + return -EOPNOTSUPP; + + switch (dev->ieee80211_ptr->iftype) { + case NL80211_IFTYPE_STATION: + case NL80211_IFTYPE_P2P_CLIENT: + break; + default: + return -EOPNOTSUPP; + } + + if (!info->attrs[NL80211_ATTR_MAC] || + !info->attrs[NL80211_ATTR_OPER_CLASS]) + return -EINVAL; + + err = nl80211_parse_chandef(rdev, info, &chandef); + if (err) + return err; + + /* + * Don't allow wide channels on the 2.4Ghz band, as per IEEE802.11-2012 + * section 10.22.6.2.1. Disallow 5/10Mhz channels as well for now, the + * specification is not defined for them. + */ + if (chandef.chan->band == IEEE80211_BAND_2GHZ && + chandef.width != NL80211_CHAN_WIDTH_20_NOHT && + chandef.width != NL80211_CHAN_WIDTH_20) + return -EINVAL; + + /* we will be active on the TDLS link */ + if (!cfg80211_reg_can_beacon(&rdev->wiphy, &chandef, wdev->iftype)) + return -EINVAL; + + /* don't allow switching to DFS channels */ + if (cfg80211_chandef_dfs_required(wdev->wiphy, &chandef, wdev->iftype)) + return -EINVAL; + + addr = nla_data(info->attrs[NL80211_ATTR_MAC]); + oper_class = nla_get_u8(info->attrs[NL80211_ATTR_OPER_CLASS]); + + wdev_lock(wdev); + err = rdev_tdls_channel_switch(rdev, dev, addr, oper_class, &chandef); + wdev_unlock(wdev); + + return err; +} + +static int nl80211_tdls_cancel_channel_switch(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]; + struct wireless_dev *wdev = dev->ieee80211_ptr; + const u8 *addr; + + if (!rdev->ops->tdls_channel_switch || + !rdev->ops->tdls_cancel_channel_switch || + !(rdev->wiphy.features & NL80211_FEATURE_TDLS_CHANNEL_SWITCH)) + return -EOPNOTSUPP; + + switch (dev->ieee80211_ptr->iftype) { + case NL80211_IFTYPE_STATION: + case NL80211_IFTYPE_P2P_CLIENT: + break; + default: + return -EOPNOTSUPP; + } + + if (!info->attrs[NL80211_ATTR_MAC]) + return -EINVAL; + + addr = nla_data(info->attrs[NL80211_ATTR_MAC]); + + wdev_lock(wdev); + rdev_tdls_cancel_channel_switch(rdev, dev, addr); + wdev_unlock(wdev); + + return 0; +} + #define NL80211_FLAG_NEED_WIPHY 0x01 #define NL80211_FLAG_NEED_NETDEV 0x02 #define NL80211_FLAG_NEED_RTNL 0x04 @@ -10456,6 +10548,22 @@ static const struct genl_ops nl80211_ops[] = { .internal_flags = NL80211_FLAG_NEED_NETDEV_UP | NL80211_FLAG_NEED_RTNL, }, + { + .cmd = NL80211_CMD_TDLS_CHANNEL_SWITCH, + .doit = nl80211_tdls_channel_switch, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + .internal_flags = NL80211_FLAG_NEED_NETDEV_UP | + NL80211_FLAG_NEED_RTNL, + }, + { + .cmd = NL80211_CMD_TDLS_CANCEL_CHANNEL_SWITCH, + .doit = nl80211_tdls_cancel_channel_switch, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + .internal_flags = NL80211_FLAG_NEED_NETDEV_UP | + NL80211_FLAG_NEED_RTNL, + }, }; /* notification functions */ diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h index 1b3864cd50ca..35cfb7134bdb 100644 --- a/net/wireless/rdev-ops.h +++ b/net/wireless/rdev-ops.h @@ -993,4 +993,28 @@ rdev_del_tx_ts(struct cfg80211_registered_device *rdev, return ret; } +static inline int +rdev_tdls_channel_switch(struct cfg80211_registered_device *rdev, + struct net_device *dev, const u8 *addr, + u8 oper_class, struct cfg80211_chan_def *chandef) +{ + int ret; + + trace_rdev_tdls_channel_switch(&rdev->wiphy, dev, addr, oper_class, + chandef); + ret = rdev->ops->tdls_channel_switch(&rdev->wiphy, dev, addr, + oper_class, chandef); + trace_rdev_return_int(&rdev->wiphy, ret); + return ret; +} + +static inline void +rdev_tdls_cancel_channel_switch(struct cfg80211_registered_device *rdev, + struct net_device *dev, const u8 *addr) +{ + trace_rdev_tdls_cancel_channel_switch(&rdev->wiphy, dev, addr); + rdev->ops->tdls_cancel_channel_switch(&rdev->wiphy, dev, addr); + trace_rdev_return_void(&rdev->wiphy); +} + #endif /* __CFG80211_RDEV_OPS */ diff --git a/net/wireless/trace.h b/net/wireless/trace.h index 6e25370d3ce7..ad38910f7036 100644 --- a/net/wireless/trace.h +++ b/net/wireless/trace.h @@ -2032,6 +2032,48 @@ TRACE_EVENT(rdev_del_tx_ts, WIPHY_PR_ARG, NETDEV_PR_ARG, MAC_PR_ARG(peer), __entry->tsid) ); +TRACE_EVENT(rdev_tdls_channel_switch, + TP_PROTO(struct wiphy *wiphy, struct net_device *netdev, + const u8 *addr, u8 oper_class, + struct cfg80211_chan_def *chandef), + TP_ARGS(wiphy, netdev, addr, oper_class, chandef), + TP_STRUCT__entry( + WIPHY_ENTRY + NETDEV_ENTRY + MAC_ENTRY(addr) + __field(u8, oper_class) + CHAN_DEF_ENTRY + ), + TP_fast_assign( + WIPHY_ASSIGN; + NETDEV_ASSIGN; + MAC_ASSIGN(addr, addr); + CHAN_DEF_ASSIGN(chandef); + ), + TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT ", " MAC_PR_FMT + " oper class %d, " CHAN_DEF_PR_FMT, + WIPHY_PR_ARG, NETDEV_PR_ARG, MAC_PR_ARG(addr), + __entry->oper_class, CHAN_DEF_PR_ARG) +); + +TRACE_EVENT(rdev_tdls_cancel_channel_switch, + TP_PROTO(struct wiphy *wiphy, struct net_device *netdev, + const u8 *addr), + TP_ARGS(wiphy, netdev, addr), + TP_STRUCT__entry( + WIPHY_ENTRY + NETDEV_ENTRY + MAC_ENTRY(addr) + ), + TP_fast_assign( + WIPHY_ASSIGN; + NETDEV_ASSIGN; + MAC_ASSIGN(addr, addr); + ), + TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT ", " MAC_PR_FMT, + WIPHY_PR_ARG, NETDEV_PR_ARG, MAC_PR_ARG(addr)) +); + /************************************************************* * cfg80211 exported functions traces * *************************************************************/