From 16ef1fe272332b2f7fd99236017b891db48d9cd6 Mon Sep 17 00:00:00 2001 From: Simon Wunderlich Date: Thu, 11 Jul 2013 16:09:05 +0200 Subject: nl80211/cfg80211: add channel switch command To allow channel switch announcements within beacons, add the channel switch command to nl80211/cfg80211. This is implementation is intended for AP and (later) IBSS mode. Signed-off-by: Simon Wunderlich Signed-off-by: Mathias Kretschmer Signed-off-by: Johannes Berg --- net/wireless/nl80211.c | 122 +++++++++++++++++++++++++++++++++++++++++++++++- net/wireless/rdev-ops.h | 12 +++++ net/wireless/trace.h | 33 +++++++++++++ 3 files changed, 166 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 03d4ef95292e..f7cb12178bd2 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -349,6 +349,11 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = { [NL80211_ATTR_IE_RIC] = { .type = NLA_BINARY, .len = IEEE80211_MAX_DATA_LEN }, [NL80211_ATTR_PEER_AID] = { .type = NLA_U16 }, + [NL80211_ATTR_CH_SWITCH_COUNT] = { .type = NLA_U32 }, + [NL80211_ATTR_CH_SWITCH_BLOCK_TX] = { .type = NLA_FLAG }, + [NL80211_ATTR_CSA_IES] = { .type = NLA_NESTED }, + [NL80211_ATTR_CSA_C_OFF_BEACON] = { .type = NLA_U16 }, + [NL80211_ATTR_CSA_C_OFF_PRESP] = { .type = NLA_U16 }, }; /* policy for the key attributes */ @@ -1422,6 +1427,8 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *dev, if (state->split) { CMD(crit_proto_start, CRIT_PROTOCOL_START); CMD(crit_proto_stop, CRIT_PROTOCOL_STOP); + if (dev->wiphy.flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH) + CMD(channel_switch, CHANNEL_SWITCH); } #ifdef CONFIG_NL80211_TESTMODE @@ -5613,6 +5620,111 @@ static int nl80211_start_radar_detection(struct sk_buff *skb, return err; } +static int nl80211_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_csa_settings params; + /* csa_attrs is defined static to avoid waste of stack size - this + * function is called under RTNL lock, so this should not be a problem. + */ + static struct nlattr *csa_attrs[NL80211_ATTR_MAX+1]; + u8 radar_detect_width = 0; + int err; + + if (!rdev->ops->channel_switch || + !(rdev->wiphy.flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH)) + return -EOPNOTSUPP; + + /* may add IBSS support later */ + if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP && + dev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO) + return -EOPNOTSUPP; + + memset(¶ms, 0, sizeof(params)); + + if (!info->attrs[NL80211_ATTR_WIPHY_FREQ] || + !info->attrs[NL80211_ATTR_CH_SWITCH_COUNT]) + return -EINVAL; + + /* only important for AP, IBSS and mesh create IEs internally */ + if (!info->attrs[NL80211_ATTR_CSA_IES]) + return -EINVAL; + + /* useless if AP is not running */ + if (!wdev->beacon_interval) + return -EINVAL; + + params.count = nla_get_u32(info->attrs[NL80211_ATTR_CH_SWITCH_COUNT]); + + err = nl80211_parse_beacon(info->attrs, ¶ms.beacon_after); + if (err) + return err; + + err = nla_parse_nested(csa_attrs, NL80211_ATTR_MAX, + info->attrs[NL80211_ATTR_CSA_IES], + nl80211_policy); + if (err) + return err; + + err = nl80211_parse_beacon(csa_attrs, ¶ms.beacon_csa); + if (err) + return err; + + if (!csa_attrs[NL80211_ATTR_CSA_C_OFF_BEACON]) + return -EINVAL; + + params.counter_offset_beacon = + nla_get_u16(csa_attrs[NL80211_ATTR_CSA_C_OFF_BEACON]); + if (params.counter_offset_beacon >= params.beacon_csa.tail_len) + return -EINVAL; + + /* sanity check - counters should be the same */ + if (params.beacon_csa.tail[params.counter_offset_beacon] != + params.count) + return -EINVAL; + + if (csa_attrs[NL80211_ATTR_CSA_C_OFF_PRESP]) { + params.counter_offset_presp = + nla_get_u16(csa_attrs[NL80211_ATTR_CSA_C_OFF_PRESP]); + if (params.counter_offset_presp >= + params.beacon_csa.probe_resp_len) + return -EINVAL; + + if (params.beacon_csa.probe_resp[params.counter_offset_presp] != + params.count) + return -EINVAL; + } + + err = nl80211_parse_chandef(rdev, info, ¶ms.chandef); + if (err) + return err; + + if (!cfg80211_reg_can_beacon(&rdev->wiphy, ¶ms.chandef)) + return -EINVAL; + + err = cfg80211_chandef_dfs_required(wdev->wiphy, ¶ms.chandef); + if (err < 0) { + return err; + } else if (err) { + radar_detect_width = BIT(params.chandef.width); + params.radar_required = true; + } + + err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype, + params.chandef.chan, + CHAN_MODE_SHARED, + radar_detect_width); + if (err) + return err; + + if (info->attrs[NL80211_ATTR_CH_SWITCH_BLOCK_TX]) + params.block_tx = true; + + return rdev_channel_switch(rdev, dev, ¶ms); +} + static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb, u32 seq, int flags, struct cfg80211_registered_device *rdev, @@ -9361,7 +9473,15 @@ static struct genl_ops nl80211_ops[] = { .flags = GENL_ADMIN_PERM, .internal_flags = NL80211_FLAG_NEED_WIPHY | NL80211_FLAG_NEED_RTNL, - } + }, + { + .cmd = NL80211_CMD_CHANNEL_SWITCH, + .doit = nl80211_channel_switch, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + .internal_flags = NL80211_FLAG_NEED_NETDEV_UP | + NL80211_FLAG_NEED_RTNL, + }, }; static struct genl_multicast_group nl80211_mlme_mcgrp = { diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h index 9f15f0ac824d..de870d4d0bcc 100644 --- a/net/wireless/rdev-ops.h +++ b/net/wireless/rdev-ops.h @@ -923,4 +923,16 @@ static inline void rdev_crit_proto_stop(struct cfg80211_registered_device *rdev, trace_rdev_return_void(&rdev->wiphy); } +static inline int rdev_channel_switch(struct cfg80211_registered_device *rdev, + struct net_device *dev, + struct cfg80211_csa_settings *params) +{ + int ret; + + trace_rdev_channel_switch(&rdev->wiphy, dev, params); + ret = rdev->ops->channel_switch(&rdev->wiphy, dev, params); + trace_rdev_return_int(&rdev->wiphy, ret); + return ret; +} + #endif /* __CFG80211_RDEV_OPS */ diff --git a/net/wireless/trace.h b/net/wireless/trace.h index 09af6eb426a8..f0ebdcd394ef 100644 --- a/net/wireless/trace.h +++ b/net/wireless/trace.h @@ -1841,6 +1841,39 @@ TRACE_EVENT(rdev_crit_proto_stop, WIPHY_PR_ARG, WDEV_PR_ARG) ); +TRACE_EVENT(rdev_channel_switch, + TP_PROTO(struct wiphy *wiphy, struct net_device *netdev, + struct cfg80211_csa_settings *params), + TP_ARGS(wiphy, netdev, params), + TP_STRUCT__entry( + WIPHY_ENTRY + NETDEV_ENTRY + CHAN_DEF_ENTRY + __field(u16, counter_offset_beacon) + __field(u16, counter_offset_presp) + __field(bool, radar_required) + __field(bool, block_tx) + __field(u8, count) + ), + TP_fast_assign( + WIPHY_ASSIGN; + NETDEV_ASSIGN; + CHAN_DEF_ASSIGN(¶ms->chandef); + __entry->counter_offset_beacon = params->counter_offset_beacon; + __entry->counter_offset_presp = params->counter_offset_presp; + __entry->radar_required = params->radar_required; + __entry->block_tx = params->block_tx; + __entry->count = params->count; + ), + TP_printk(WIPHY_PR_FMT ", " NETDEV_PR_FMT ", " CHAN_DEF_PR_FMT + ", block_tx: %d, count: %u, radar_required: %d" + ", counter offsets (beacon/presp): %u/%u", + WIPHY_PR_ARG, NETDEV_PR_ARG, CHAN_DEF_PR_ARG, + __entry->block_tx, __entry->count, __entry->radar_required, + __entry->counter_offset_beacon, + __entry->counter_offset_presp) +); + /************************************************************* * cfg80211 exported functions traces * *************************************************************/ -- cgit v1.2.3-59-g8ed1b