From 9588bbd5529461a3dacd435bf239c84c3508f569 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Wed, 23 Dec 2009 13:15:41 +0100 Subject: cfg80211: add remain-on-channel command Add new commands for requesting the driver to remain awake on a specified channel for the specified amount of time (and another command to cancel such an operation). This can be used to implement userspace-controlled off-channel operations, like Public Action frame exchange on another channel than the operation channel. The off-channel operation should behave similarly to scan, i.e. the local station (if associated) moves into power save mode to request the AP to buffer frames for it and then moves to the other channel to allow the off-channel operation to be completed. The duration parameter can be used to request enough time to receive a response from the target station. Signed-off-by: Jouni Malinen Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/wireless/nl80211.c | 218 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 217 insertions(+), 1 deletion(-) (limited to 'net/wireless/nl80211.c') diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 60f8543..ff857f1 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -141,6 +141,8 @@ static struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] __read_mostly = { [NL80211_ATTR_4ADDR] = { .type = NLA_U8 }, [NL80211_ATTR_PMKID] = { .type = NLA_BINARY, .len = WLAN_PMKID_LEN }, + [NL80211_ATTR_DURATION] = { .type = NLA_U32 }, + [NL80211_ATTR_COOKIE] = { .type = NLA_U64 }, }; /* policy for the attributes */ @@ -569,6 +571,7 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags, CMD(set_pmksa, SET_PMKSA); CMD(del_pmksa, DEL_PMKSA); CMD(flush_pmksa, FLUSH_PMKSA); + CMD(remain_on_channel, REMAIN_ON_CHANNEL); if (dev->wiphy.flags & WIPHY_FLAG_NETNS_OK) { i++; NLA_PUT_U32(msg, i, NL80211_CMD_SET_WIPHY_NETNS); @@ -4283,6 +4286,143 @@ static int nl80211_flush_pmksa(struct sk_buff *skb, struct genl_info *info) } +static int nl80211_remain_on_channel(struct sk_buff *skb, + struct genl_info *info) +{ + struct cfg80211_registered_device *rdev; + struct net_device *dev; + struct ieee80211_channel *chan; + struct sk_buff *msg; + void *hdr; + u64 cookie; + enum nl80211_channel_type channel_type = NL80211_CHAN_NO_HT; + u32 freq, duration; + int err; + + if (!info->attrs[NL80211_ATTR_WIPHY_FREQ] || + !info->attrs[NL80211_ATTR_DURATION]) + return -EINVAL; + + duration = nla_get_u32(info->attrs[NL80211_ATTR_DURATION]); + + /* + * We should be on that channel for at least one jiffie, + * and more than 5 seconds seems excessive. + */ + if (!duration || !msecs_to_jiffies(duration) || duration > 5000) + return -EINVAL; + + rtnl_lock(); + + err = get_rdev_dev_by_info_ifindex(info, &rdev, &dev); + if (err) + goto unlock_rtnl; + + if (!rdev->ops->remain_on_channel) { + err = -EOPNOTSUPP; + goto out; + } + + if (!netif_running(dev)) { + err = -ENETDOWN; + goto out; + } + + if (info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]) { + channel_type = nla_get_u32( + info->attrs[NL80211_ATTR_WIPHY_CHANNEL_TYPE]); + if (channel_type != NL80211_CHAN_NO_HT && + channel_type != NL80211_CHAN_HT20 && + channel_type != NL80211_CHAN_HT40PLUS && + channel_type != NL80211_CHAN_HT40MINUS) + err = -EINVAL; + goto out; + } + + freq = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_FREQ]); + chan = rdev_freq_to_chan(rdev, freq, channel_type); + if (chan == NULL) { + err = -EINVAL; + goto out; + } + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) { + err = -ENOMEM; + goto out; + } + + hdr = nl80211hdr_put(msg, info->snd_pid, info->snd_seq, 0, + NL80211_CMD_REMAIN_ON_CHANNEL); + + if (IS_ERR(hdr)) { + err = PTR_ERR(hdr); + goto free_msg; + } + + err = rdev->ops->remain_on_channel(&rdev->wiphy, dev, chan, + channel_type, duration, &cookie); + + if (err) + goto free_msg; + + NLA_PUT_U64(msg, NL80211_ATTR_COOKIE, cookie); + + genlmsg_end(msg, hdr); + err = genlmsg_reply(msg, info); + goto out; + + nla_put_failure: + err = -ENOBUFS; + free_msg: + nlmsg_free(msg); + out: + cfg80211_unlock_rdev(rdev); + dev_put(dev); + unlock_rtnl: + rtnl_unlock(); + return err; +} + +static int nl80211_cancel_remain_on_channel(struct sk_buff *skb, + struct genl_info *info) +{ + struct cfg80211_registered_device *rdev; + struct net_device *dev; + u64 cookie; + int err; + + if (!info->attrs[NL80211_ATTR_COOKIE]) + return -EINVAL; + + rtnl_lock(); + + err = get_rdev_dev_by_info_ifindex(info, &rdev, &dev); + if (err) + goto unlock_rtnl; + + if (!rdev->ops->cancel_remain_on_channel) { + err = -EOPNOTSUPP; + goto out; + } + + if (!netif_running(dev)) { + err = -ENETDOWN; + goto out; + } + + cookie = nla_get_u64(info->attrs[NL80211_ATTR_COOKIE]); + + err = rdev->ops->cancel_remain_on_channel(&rdev->wiphy, dev, cookie); + + out: + cfg80211_unlock_rdev(rdev); + dev_put(dev); + unlock_rtnl: + rtnl_unlock(); + return err; +} + static struct genl_ops nl80211_ops[] = { { .cmd = NL80211_CMD_GET_WIPHY, @@ -4545,8 +4685,20 @@ static struct genl_ops nl80211_ops[] = { .policy = nl80211_policy, .flags = GENL_ADMIN_PERM, }, - + { + .cmd = NL80211_CMD_REMAIN_ON_CHANNEL, + .doit = nl80211_remain_on_channel, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = NL80211_CMD_CANCEL_REMAIN_ON_CHANNEL, + .doit = nl80211_cancel_remain_on_channel, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + }, }; + static struct genl_multicast_group nl80211_mlme_mcgrp = { .name = "mlme", }; @@ -5134,6 +5286,70 @@ nla_put_failure: nlmsg_free(msg); } +static void nl80211_send_remain_on_chan_event( + int cmd, struct cfg80211_registered_device *rdev, + struct net_device *netdev, u64 cookie, + struct ieee80211_channel *chan, + enum nl80211_channel_type channel_type, + unsigned int duration, gfp_t gfp) +{ + struct sk_buff *msg; + void *hdr; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); + if (!msg) + return; + + hdr = nl80211hdr_put(msg, 0, 0, 0, cmd); + if (!hdr) { + nlmsg_free(msg); + return; + } + + NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx); + NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, netdev->ifindex); + NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_FREQ, chan->center_freq); + NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_CHANNEL_TYPE, channel_type); + NLA_PUT_U64(msg, NL80211_ATTR_COOKIE, cookie); + + if (cmd == NL80211_CMD_REMAIN_ON_CHANNEL) + NLA_PUT_U32(msg, NL80211_ATTR_DURATION, duration); + + if (genlmsg_end(msg, hdr) < 0) { + nlmsg_free(msg); + return; + } + + genlmsg_multicast_netns(wiphy_net(&rdev->wiphy), msg, 0, + nl80211_mlme_mcgrp.id, gfp); + return; + + nla_put_failure: + genlmsg_cancel(msg, hdr); + nlmsg_free(msg); +} + +void nl80211_send_remain_on_channel(struct cfg80211_registered_device *rdev, + struct net_device *netdev, u64 cookie, + struct ieee80211_channel *chan, + enum nl80211_channel_type channel_type, + unsigned int duration, gfp_t gfp) +{ + nl80211_send_remain_on_chan_event(NL80211_CMD_REMAIN_ON_CHANNEL, + rdev, netdev, cookie, chan, + channel_type, duration, gfp); +} + +void nl80211_send_remain_on_channel_cancel( + struct cfg80211_registered_device *rdev, struct net_device *netdev, + u64 cookie, struct ieee80211_channel *chan, + enum nl80211_channel_type channel_type, gfp_t gfp) +{ + nl80211_send_remain_on_chan_event(NL80211_CMD_CANCEL_REMAIN_ON_CHANNEL, + rdev, netdev, cookie, chan, + channel_type, 0, gfp); +} + /* initialisation/exit functions */ int nl80211_init(void) -- cgit v1.1