diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 05aae22e92a5..bb748c4da5af 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1437,6 +1437,10 @@ struct cfg80211_ssid { * @aborted: (internal) scan request was notified as aborted * @notified: (internal) scan request was notified as done or aborted * @no_cck: used to send probe requests at non CCK rate in 2GHz band + * @mac_addr: MAC address used with randomisation + * @mac_addr_mask: MAC address mask used with randomisation, bits that + * are 0 in the mask should be randomised, bits that are 1 should + * be taken from the @mac_addr */ struct cfg80211_scan_request { struct cfg80211_ssid *ssids; @@ -1451,6 +1455,9 @@ struct cfg80211_scan_request { struct wireless_dev *wdev; + u8 mac_addr[ETH_ALEN] __aligned(2); + u8 mac_addr_mask[ETH_ALEN] __aligned(2); + /* internal */ struct wiphy *wiphy; unsigned long scan_start; @@ -1461,6 +1468,17 @@ struct cfg80211_scan_request { struct ieee80211_channel *channels[0]; }; +static inline void get_random_mask_addr(u8 *buf, const u8 *addr, const u8 *mask) +{ + int i; + + get_random_bytes(buf, ETH_ALEN); + for (i = 0; i < ETH_ALEN; i++) { + buf[i] &= ~mask[i]; + buf[i] |= addr[i] & mask[i]; + } +} + /** * struct cfg80211_match_set - sets of attributes to match * @@ -1494,6 +1512,10 @@ struct cfg80211_match_set { * @channels: channels to scan * @min_rssi_thold: for drivers only supporting a single threshold, this * contains the minimum over all matchsets + * @mac_addr: MAC address used with randomisation + * @mac_addr_mask: MAC address mask used with randomisation, bits that + * are 0 in the mask should be randomised, bits that are 1 should + * be taken from the @mac_addr */ struct cfg80211_sched_scan_request { struct cfg80211_ssid *ssids; @@ -1508,6 +1530,9 @@ struct cfg80211_sched_scan_request { int n_match_sets; s32 min_rssi_thold; + u8 mac_addr[ETH_ALEN] __aligned(2); + u8 mac_addr_mask[ETH_ALEN] __aligned(2); + /* internal */ struct wiphy *wiphy; struct net_device *dev; diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index d23208194e3c..a99081efc2d4 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -1686,6 +1686,8 @@ enum nl80211_commands { * * @NL80211_ATTR_OPER_CLASS: operating class * + * @NL80211_ATTR_MAC_MASK: MAC address mask + * * @NUM_NL80211_ATTR: total number of nl80211_attrs available * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use @@ -2041,6 +2043,8 @@ enum nl80211_attrs { NL80211_ATTR_OPER_CLASS, + NL80211_ATTR_MAC_MASK, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, @@ -4139,6 +4143,18 @@ enum nl80211_ap_sme_features { * See 'macaddr' field in the vif_params (cfg80211.h). * @NL80211_FEATURE_TDLS_CHANNEL_SWITCH: Driver supports channel switching when * operating as a TDLS peer. + * @NL80211_FEATURE_SCAN_RANDOM_MAC_ADDR: This device/driver supports using a + * random MAC address during scan (if the device is unassociated); the + * %NL80211_SCAN_FLAG_RANDOM_ADDR flag may be set for scans and the MAC + * address mask/value will be used. + * @NL80211_FEATURE_SCHED_SCAN_RANDOM_MAC_ADDR: This device/driver supports + * using a random MAC address for every scan iteration during scheduled + * scan (while not associated), the %NL80211_SCAN_FLAG_RANDOM_ADDR may + * be set for scheduled scan and the MAC address mask/value will be used. + * @NL80211_FEATURE_ND_RANDOM_MAC_ADDR: This device/driver supports using a + * random MAC address for every scan iteration during "net detect", i.e. + * scan in unassociated WoWLAN, the %NL80211_SCAN_FLAG_RANDOM_ADDR may + * be set for scheduled scan and the MAC address mask/value will be used. */ enum nl80211_feature_flags { NL80211_FEATURE_SK_TX_STATUS = 1 << 0, @@ -4170,6 +4186,9 @@ enum nl80211_feature_flags { NL80211_FEATURE_SUPPORTS_WMM_ADMISSION = 1 << 26, NL80211_FEATURE_MAC_ON_CREATE = 1 << 27, NL80211_FEATURE_TDLS_CHANNEL_SWITCH = 1 << 28, + NL80211_FEATURE_SCAN_RANDOM_MAC_ADDR = 1 << 29, + NL80211_FEATURE_SCHED_SCAN_RANDOM_MAC_ADDR = 1 << 30, + NL80211_FEATURE_ND_RANDOM_MAC_ADDR = 1 << 31, }; /** @@ -4218,11 +4237,21 @@ enum nl80211_connect_failed_reason { * dangerous because will destroy stations performance as a lot of frames * will be lost while scanning off-channel, therefore it must be used only * when really needed + * @NL80211_SCAN_FLAG_RANDOM_ADDR: use a random MAC address for this scan (or + * for scheduled scan: a different one for every scan iteration). When the + * flag is set, depending on device capabilities the @NL80211_ATTR_MAC and + * @NL80211_ATTR_MAC_MASK attributes may also be given in which case only + * the masked bits will be preserved from the MAC address and the remainder + * randomised. If the attributes are not given full randomisation (46 bits, + * locally administered 1, multicast 0) is assumed. + * This flag must not be requested when the feature isn't supported, check + * the nl80211 feature flags for the device. */ enum nl80211_scan_flags { NL80211_SCAN_FLAG_LOW_PRIORITY = 1<<0, NL80211_SCAN_FLAG_FLUSH = 1<<1, NL80211_SCAN_FLAG_AP = 1<<2, + NL80211_SCAN_FLAG_RANDOM_ADDR = 1<<3, }; /** diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 3ec7dc557960..dd5a827f9cb0 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -395,6 +395,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = { [NL80211_ATTR_USER_PRIO] = { .type = NLA_U8 }, [NL80211_ATTR_ADMITTED_TIME] = { .type = NLA_U16 }, [NL80211_ATTR_SMPS_MODE] = { .type = NLA_U8 }, + [NL80211_ATTR_MAC_MASK] = { .len = ETH_ALEN }, }; /* policy for the key attributes */ @@ -5481,6 +5482,43 @@ static int validate_scan_freqs(struct nlattr *freqs) return n_channels; } +static int nl80211_parse_random_mac(struct nlattr **attrs, + u8 *mac_addr, u8 *mac_addr_mask) +{ + int i; + + if (!attrs[NL80211_ATTR_MAC] && !attrs[NL80211_ATTR_MAC_MASK]) { + memset(mac_addr, 0, ETH_ALEN); + memset(mac_addr_mask, 0, ETH_ALEN); + mac_addr[0] = 0x2; + mac_addr_mask[0] = 0x3; + + return 0; + } + + /* need both or none */ + if (!attrs[NL80211_ATTR_MAC] || !attrs[NL80211_ATTR_MAC_MASK]) + return -EINVAL; + + memcpy(mac_addr, nla_data(attrs[NL80211_ATTR_MAC]), ETH_ALEN); + memcpy(mac_addr_mask, nla_data(attrs[NL80211_ATTR_MAC_MASK]), ETH_ALEN); + + /* don't allow or configure an mcast address */ + if (!is_multicast_ether_addr(mac_addr_mask) || + is_multicast_ether_addr(mac_addr)) + return -EINVAL; + + /* + * allow users to pass a MAC address that has bits set outside + * of the mask, but don't bother drivers with having to deal + * with such bits + */ + for (i = 0; i < ETH_ALEN; i++) + mac_addr[i] &= mac_addr_mask[i]; + + return 0; +} + static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info) { struct cfg80211_registered_device *rdev = info->user_ptr[0]; @@ -5658,6 +5696,25 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info) err = -EOPNOTSUPP; goto out_free; } + + if (request->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) { + if (!(wiphy->features & + NL80211_FEATURE_SCAN_RANDOM_MAC_ADDR)) { + err = -EOPNOTSUPP; + goto out_free; + } + + if (wdev->current_bss) { + err = -EOPNOTSUPP; + goto out_free; + } + + err = nl80211_parse_random_mac(info->attrs, + request->mac_addr, + request->mac_addr_mask); + if (err) + goto out_free; + } } request->no_cck = @@ -5685,7 +5742,7 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info) } static struct cfg80211_sched_scan_request * -nl80211_parse_sched_scan(struct wiphy *wiphy, +nl80211_parse_sched_scan(struct wiphy *wiphy, struct wireless_dev *wdev, struct nlattr **attrs) { struct cfg80211_sched_scan_request *request; @@ -5934,6 +5991,28 @@ nl80211_parse_sched_scan(struct wiphy *wiphy, err = -EOPNOTSUPP; goto out_free; } + + if (request->flags & NL80211_SCAN_FLAG_RANDOM_ADDR) { + u32 flg = NL80211_FEATURE_SCHED_SCAN_RANDOM_MAC_ADDR; + + if (!wdev) /* must be net-detect */ + flg = NL80211_FEATURE_ND_RANDOM_MAC_ADDR; + + if (!(wiphy->features & flg)) { + err = -EOPNOTSUPP; + goto out_free; + } + + if (wdev && wdev->current_bss) { + err = -EOPNOTSUPP; + goto out_free; + } + + err = nl80211_parse_random_mac(attrs, request->mac_addr, + request->mac_addr_mask); + if (err) + goto out_free; + } } request->interval = interval; @@ -5951,6 +6030,7 @@ static int nl80211_start_sched_scan(struct sk_buff *skb, { struct cfg80211_registered_device *rdev = info->user_ptr[0]; struct net_device *dev = info->user_ptr[1]; + struct wireless_dev *wdev = dev->ieee80211_ptr; int err; if (!(rdev->wiphy.flags & WIPHY_FLAG_SUPPORTS_SCHED_SCAN) || @@ -5960,7 +6040,7 @@ static int nl80211_start_sched_scan(struct sk_buff *skb, if (rdev->sched_scan_req) return -EINPROGRESS; - rdev->sched_scan_req = nl80211_parse_sched_scan(&rdev->wiphy, + rdev->sched_scan_req = nl80211_parse_sched_scan(&rdev->wiphy, wdev, info->attrs); err = PTR_ERR_OR_ZERO(rdev->sched_scan_req); if (err) @@ -8721,7 +8801,7 @@ static int nl80211_parse_wowlan_nd(struct cfg80211_registered_device *rdev, if (err) goto out; - trig->nd_config = nl80211_parse_sched_scan(&rdev->wiphy, tb); + trig->nd_config = nl80211_parse_sched_scan(&rdev->wiphy, NULL, tb); err = PTR_ERR_OR_ZERO(trig->nd_config); if (err) trig->nd_config = NULL;