From 9860d9be89f420f3793fb798faadea11c723e08a Mon Sep 17 00:00:00 2001 From: Miquel Raynal Date: Wed, 27 Sep 2023 20:12:09 +0200 Subject: mac802154: Handle disassociations Devices may decide to disassociate from their coordinator for different reasons (device turning off, coordinator signal strength too low, etc), the MAC layer just has to send a disassociation notification. If the ack of the disassociation notification is not received, the device may consider itself disassociated anyway. Signed-off-by: Miquel Raynal Acked-by: Stefan Schmidt Acked-by: Alexander Aring Link: https://lore.kernel.org/linux-wpan/20230927181214.129346-7-miquel.raynal@bootlin.com --- net/mac802154/cfg.c | 100 +++++++++++++++++++++++++++++++++++++++++++ net/mac802154/ieee802154_i.h | 4 ++ net/mac802154/scan.c | 60 ++++++++++++++++++++++++++ 3 files changed, 164 insertions(+) (limited to 'net/mac802154') diff --git a/net/mac802154/cfg.c b/net/mac802154/cfg.c index 0e8bb1486430..083de2d3fe37 100644 --- a/net/mac802154/cfg.c +++ b/net/mac802154/cfg.c @@ -383,6 +383,105 @@ free_parent: return ret; } +static int mac802154_disassociate_from_parent(struct wpan_phy *wpan_phy, + struct wpan_dev *wpan_dev) +{ + struct ieee802154_local *local = wpan_phy_priv(wpan_phy); + struct ieee802154_pan_device *child, *tmp; + struct ieee802154_sub_if_data *sdata; + u64 eaddr; + int ret; + + sdata = IEEE802154_WPAN_DEV_TO_SUB_IF(wpan_dev); + + /* Start by disassociating all the children and preventing new ones to + * attempt associations. + */ + list_for_each_entry_safe(child, tmp, &wpan_dev->children, node) { + ret = mac802154_send_disassociation_notif(sdata, child, + IEEE802154_COORD_WISHES_DEVICE_TO_LEAVE); + if (ret) { + eaddr = swab64((__force u64)child->extended_addr); + dev_err(&sdata->dev->dev, + "Disassociation with %8phC may have failed (%d)\n", + &eaddr, ret); + } + + list_del(&child->node); + } + + ret = mac802154_send_disassociation_notif(sdata, wpan_dev->parent, + IEEE802154_DEVICE_WISHES_TO_LEAVE); + if (ret) { + eaddr = swab64((__force u64)wpan_dev->parent->extended_addr); + dev_err(&sdata->dev->dev, + "Disassociation from %8phC may have failed (%d)\n", + &eaddr, ret); + } + + ret = 0; + + kfree(wpan_dev->parent); + wpan_dev->parent = NULL; + wpan_dev->pan_id = cpu_to_le16(IEEE802154_PAN_ID_BROADCAST); + wpan_dev->short_addr = cpu_to_le16(IEEE802154_ADDR_SHORT_BROADCAST); + + if (local->hw.flags & IEEE802154_HW_AFILT) { + ret = drv_set_pan_id(local, wpan_dev->pan_id); + if (ret < 0) + return ret; + + ret = drv_set_short_addr(local, wpan_dev->short_addr); + if (ret < 0) + return ret; + } + + return 0; +} + +static int mac802154_disassociate_child(struct wpan_phy *wpan_phy, + struct wpan_dev *wpan_dev, + struct ieee802154_pan_device *child) +{ + struct ieee802154_sub_if_data *sdata; + int ret; + + sdata = IEEE802154_WPAN_DEV_TO_SUB_IF(wpan_dev); + + ret = mac802154_send_disassociation_notif(sdata, child, + IEEE802154_COORD_WISHES_DEVICE_TO_LEAVE); + if (ret) + return ret; + + list_del(&child->node); + kfree(child); + + return 0; +} + +static int mac802154_disassociate(struct wpan_phy *wpan_phy, + struct wpan_dev *wpan_dev, + struct ieee802154_addr *target) +{ + u64 teaddr = swab64((__force u64)target->extended_addr); + struct ieee802154_pan_device *pan_device; + + ASSERT_RTNL(); + + if (cfg802154_device_is_parent(wpan_dev, target)) + return mac802154_disassociate_from_parent(wpan_phy, wpan_dev); + + pan_device = cfg802154_device_is_child(wpan_dev, target); + if (pan_device) + return mac802154_disassociate_child(wpan_phy, wpan_dev, + pan_device); + + dev_err(&wpan_dev->netdev->dev, + "Device %8phC is not associated with us\n", &teaddr); + + return -EINVAL; +} + #ifdef CONFIG_IEEE802154_NL802154_EXPERIMENTAL static void ieee802154_get_llsec_table(struct wpan_phy *wpan_phy, @@ -595,6 +694,7 @@ const struct cfg802154_ops mac802154_config_ops = { .send_beacons = mac802154_send_beacons, .stop_beacons = mac802154_stop_beacons, .associate = mac802154_associate, + .disassociate = mac802154_disassociate, #ifdef CONFIG_IEEE802154_NL802154_EXPERIMENTAL .get_llsec_table = ieee802154_get_llsec_table, .lock_llsec_table = ieee802154_lock_llsec_table, diff --git a/net/mac802154/ieee802154_i.h b/net/mac802154/ieee802154_i.h index fff67676b400..92252f86c69c 100644 --- a/net/mac802154/ieee802154_i.h +++ b/net/mac802154/ieee802154_i.h @@ -315,6 +315,10 @@ static inline bool mac802154_is_associating(struct ieee802154_local *local) return test_bit(IEEE802154_IS_ASSOCIATING, &local->ongoing); } +int mac802154_send_disassociation_notif(struct ieee802154_sub_if_data *sdata, + struct ieee802154_pan_device *target, + u8 reason); + /* interface handling */ int ieee802154_iface_init(void); void ieee802154_iface_exit(void); diff --git a/net/mac802154/scan.c b/net/mac802154/scan.c index 5dd50e1ce329..e2f2e1235ec6 100644 --- a/net/mac802154/scan.c +++ b/net/mac802154/scan.c @@ -637,3 +637,63 @@ int mac802154_process_association_resp(struct ieee802154_sub_if_data *sdata, return 0; } + +int mac802154_send_disassociation_notif(struct ieee802154_sub_if_data *sdata, + struct ieee802154_pan_device *target, + u8 reason) +{ + struct ieee802154_disassociation_notif_frame frame = {}; + u64 teaddr = swab64((__force u64)target->extended_addr); + struct ieee802154_local *local = sdata->local; + struct wpan_dev *wpan_dev = &sdata->wpan_dev; + struct sk_buff *skb; + int ret; + + frame.mhr.fc.type = IEEE802154_FC_TYPE_MAC_CMD; + frame.mhr.fc.security_enabled = 0; + frame.mhr.fc.frame_pending = 0; + frame.mhr.fc.ack_request = 1; + frame.mhr.fc.intra_pan = 1; + frame.mhr.fc.dest_addr_mode = (target->mode == IEEE802154_ADDR_LONG) ? + IEEE802154_EXTENDED_ADDRESSING : IEEE802154_SHORT_ADDRESSING; + frame.mhr.fc.version = IEEE802154_2003_STD; + frame.mhr.fc.source_addr_mode = IEEE802154_EXTENDED_ADDRESSING; + frame.mhr.source.mode = IEEE802154_ADDR_LONG; + frame.mhr.source.pan_id = wpan_dev->pan_id; + frame.mhr.source.extended_addr = wpan_dev->extended_addr; + frame.mhr.dest.mode = target->mode; + frame.mhr.dest.pan_id = wpan_dev->pan_id; + if (target->mode == IEEE802154_ADDR_LONG) + frame.mhr.dest.extended_addr = target->extended_addr; + else + frame.mhr.dest.short_addr = target->short_addr; + frame.mhr.seq = atomic_inc_return(&wpan_dev->dsn) & 0xFF; + frame.mac_pl.cmd_id = IEEE802154_CMD_DISASSOCIATION_NOTIFY; + frame.disassoc_pl = reason; + + skb = alloc_skb(IEEE802154_MAC_CMD_SKB_SZ + sizeof(frame.disassoc_pl), + GFP_KERNEL); + if (!skb) + return -ENOBUFS; + + skb->dev = sdata->dev; + + ret = ieee802154_mac_cmd_push(skb, &frame, &frame.disassoc_pl, + sizeof(frame.disassoc_pl)); + if (ret) { + kfree_skb(skb); + return ret; + } + + ret = ieee802154_mlme_tx_one_locked(local, sdata, skb); + if (ret) { + dev_warn(&sdata->dev->dev, + "No DISASSOC ACK received from %8phC\n", &teaddr); + if (ret > 0) + ret = (ret == IEEE802154_NO_ACK) ? -EREMOTEIO : -EIO; + return ret; + } + + dev_dbg(&sdata->dev->dev, "DISASSOC ACK received from %8phC\n", &teaddr); + return 0; +} -- cgit