From 7f6cf311a594c1e7ca8120367dd1d4c685aabff1 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 4 Nov 2011 11:18:15 +0100 Subject: [PATCH] nl80211: add API to probe a client When the AP SME in hostapd is used it wants to probe the clients when they have been idle for some time. Add explicit API to support this. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- include/linux/nl80211.h | 10 +++++ include/net/cfg80211.h | 17 ++++++++ net/wireless/nl80211.c | 104 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 131 insertions(+) diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h index ff39e4b..901a70d 100644 --- a/include/linux/nl80211.h +++ b/include/linux/nl80211.h @@ -519,6 +519,14 @@ * If used as the command it must have an interface index and you can * only unsubscribe from the event by closing the socket. * + * @NL80211_CMD_PROBE_CLIENT: Probe an associated station on an AP interface + * by sending a null data frame to it and reporting when the frame is + * acknowleged. This is used to allow timing out inactive clients. Uses + * %NL80211_ATTR_IFINDEX and %NL80211_ATTR_MAC. The command returns a + * direct reply with an %NL80211_ATTR_COOKIE that is later used to match + * up the event with the request. The event includes the same data and + * has %NL80211_ATTR_ACK set if the frame was ACKed. + * * @NL80211_CMD_MAX: highest used command number * @__NL80211_CMD_AFTER_LAST: internal use */ @@ -650,6 +658,8 @@ enum nl80211_commands { NL80211_CMD_UNEXPECTED_FRAME, + NL80211_CMD_PROBE_CLIENT, + /* add new commands above here */ /* used to define NL80211_CMD_MAX below */ diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 86d207d..389e85e 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1432,6 +1432,9 @@ struct cfg80211_gtk_rekey_data { * * @tdls_mgmt: Transmit a TDLS management frame. * @tdls_oper: Perform a high-level TDLS operation (e.g. TDLS link setup). + * + * @probe_client: probe an associated client, must return a cookie that it + * later passes to cfg80211_probe_status(). */ struct cfg80211_ops { int (*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow); @@ -1621,6 +1624,9 @@ struct cfg80211_ops { u16 status_code, const u8 *buf, size_t len); int (*tdls_oper)(struct wiphy *wiphy, struct net_device *dev, u8 *peer, enum nl80211_tdls_operation oper); + + int (*probe_client)(struct wiphy *wiphy, struct net_device *dev, + const u8 *peer, u64 *cookie); }; /* @@ -3216,6 +3222,17 @@ void cfg80211_pmksa_candidate_notify(struct net_device *dev, int index, bool cfg80211_rx_spurious_frame(struct net_device *dev, const u8 *addr, gfp_t gfp); +/** + * cfg80211_probe_status - notify userspace about probe status + * @dev: the device the probe was sent on + * @addr: the address of the peer + * @cookie: the cookie filled in @probe_client previously + * @acked: indicates whether probe was acked or not + * @gfp: allocation flags + */ +void cfg80211_probe_status(struct net_device *dev, const u8 *addr, + u64 cookie, bool acked, gfp_t gfp); + /* Logging, debugging and troubleshooting/diagnostic helpers. */ /* wiphy_printk helpers, similar to dev_printk */ diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 2094c84..a8eda12 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -890,6 +890,7 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags, } if (dev->wiphy.flags & WIPHY_FLAG_SUPPORTS_SCHED_SCAN) CMD(sched_scan_start, START_SCHED_SCAN); + CMD(probe_client, PROBE_CLIENT); #undef CMD @@ -5853,6 +5854,59 @@ static int nl80211_register_unexpected_frame(struct sk_buff *skb, return 0; } +static int nl80211_probe_client(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 sk_buff *msg; + void *hdr; + const u8 *addr; + u64 cookie; + int err; + + if (wdev->iftype != NL80211_IFTYPE_AP && + wdev->iftype != NL80211_IFTYPE_P2P_GO) + return -EOPNOTSUPP; + + if (!info->attrs[NL80211_ATTR_MAC]) + return -EINVAL; + + if (!rdev->ops->probe_client) + return -EOPNOTSUPP; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + hdr = nl80211hdr_put(msg, info->snd_pid, info->snd_seq, 0, + NL80211_CMD_PROBE_CLIENT); + + if (IS_ERR(hdr)) { + err = PTR_ERR(hdr); + goto free_msg; + } + + addr = nla_data(info->attrs[NL80211_ATTR_MAC]); + + err = rdev->ops->probe_client(&rdev->wiphy, dev, addr, &cookie); + if (err) + goto free_msg; + + NLA_PUT_U64(msg, NL80211_ATTR_COOKIE, cookie); + + genlmsg_end(msg, hdr); + + return genlmsg_reply(msg, info); + + nla_put_failure: + err = -ENOBUFS; + free_msg: + nlmsg_free(msg); + return err; +} + #define NL80211_FLAG_NEED_WIPHY 0x01 #define NL80211_FLAG_NEED_NETDEV 0x02 #define NL80211_FLAG_NEED_RTNL 0x04 @@ -6416,6 +6470,14 @@ static struct genl_ops nl80211_ops[] = { .internal_flags = NL80211_FLAG_NEED_NETDEV | NL80211_FLAG_NEED_RTNL, }, + { + .cmd = NL80211_CMD_PROBE_CLIENT, + .doit = nl80211_probe_client, + .policy = nl80211_policy, + .flags = GENL_ADMIN_PERM, + .internal_flags = NL80211_FLAG_NEED_NETDEV | + NL80211_FLAG_NEED_RTNL, + }, }; static struct genl_multicast_group nl80211_mlme_mcgrp = { @@ -7478,6 +7540,48 @@ nl80211_send_cqm_pktloss_notify(struct cfg80211_registered_device *rdev, nlmsg_free(msg); } +void cfg80211_probe_status(struct net_device *dev, const u8 *addr, + u64 cookie, bool acked, gfp_t gfp) +{ + struct wireless_dev *wdev = dev->ieee80211_ptr; + struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy); + struct sk_buff *msg; + void *hdr; + int err; + + msg = nlmsg_new(NLMSG_GOODSIZE, gfp); + if (!msg) + return; + + hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_PROBE_CLIENT); + if (!hdr) { + nlmsg_free(msg); + return; + } + + NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx); + NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, dev->ifindex); + NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, addr); + NLA_PUT_U64(msg, NL80211_ATTR_COOKIE, cookie); + if (acked) + NLA_PUT_FLAG(msg, NL80211_ATTR_ACK); + + err = genlmsg_end(msg, hdr); + if (err < 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); +} +EXPORT_SYMBOL(cfg80211_probe_status); + static int nl80211_netlink_notify(struct notifier_block * nb, unsigned long state, void *_notify) -- 2.7.4